PG EMRpgemr.org/sites/default/files/Book of abstracts IV Forum...3 Scientific Committee Julia...
Transcript of PG EMRpgemr.org/sites/default/files/Book of abstracts IV Forum...3 Scientific Committee Julia...
Honorary patronage:
Dean of the Faculty of Physics, Adam Mickiewicz University
Professor dr hab. Antoni Wójcik
Director of the Institute of Molecular Physics Polish Academy of Sciences
Professor dr hab. Bogdan Idzikowski
Organizers:
Sponsors:
Streszczenia przyjęto do druku bez poprawek merytorycznych
i na odpowiedzialność autorów
Zdjęcie na okładce: Ratusz w Poznaniu, Poznań 2016
Autor zdjęcia: Karol Tuśnio
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Scientific Committee
Julia Jezierska – University of Wroclaw, Wrocław
Kazimierz Dziliński – University of Technology, Częstochowa
Nikos Guskos – West Pomeranian University of Technology, Szczecin
Stanisław Hoffmann – Institute of Molecular Physics PAS, Poznań
Wojciech Kempiński – Institute of Molecular Physics PAS, Poznań
Małgorzata Komorowska – University of Technology, Wrocław
Ryszard Krzyminiewski – Adam Mickiewicz University, Poznań
Jerzy Krzystek – Florida State University, Tallahassee
Marian Kuźma – University of Rzeszów, Rzeszów
Jacek Michalik – Institute of Nuclear Chemistry and Technology, Warszawa
Andrzej Ożarowski – Florida State University, Tallahassee
Bohdan Padlyak – University of Zielona Góra, Zielona Góra
Lidia Piekara-Sady – Institute of Molecular Physics PAS, Poznań
Barbara Pilawa – Medical University of Silesia, Katowice
Czesław Rudowicz – West Pomeranian University of Technology, Szczecin & Adam
Mickiewicz University, Poznań
Zbigniew Sojka – Jagiellonian University, Kraków
Ewa Szajdzińska-Piętek – University of Technology, Łódź
Zbigniew Trybuła – Institute of Molecular Physics PAS, Poznań
Stefan Waplak – Institute of Molecular Physics PAS, Poznań
Organizing Committee
Wojciech Kempiński – Chairman IMP PAS
Ryszard Krzyminiewski – Chairman AMU
Czesław Rudowicz – Chairman of the PG EMR
Magdalena Wencka – Secretary
Waldemar Bednarski
Adam Ostrowski
Szymon Łoś
Maria Augustyniak-Jabłokow
Aldona Krupska
Bernadeta Dobosz
Agnieszka Boś-Liedke
Tomasz Kubiak
Krzysztof Tadyszak
Piotr Decyk
Alina Zalewska
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Welcome Address
Honoured Guests, Ladies and Gentlemen:
On behalf of the Council of the Polish EMR Group and the Local Organising Committee,
co-chaired by Prof. Wojciech Kempiński (Institute of Molecular Physics, Polish Academy of
Sciences [PAS]) and Prof. Ryszard Krzyminiewski (Faculty of Physics, Adam Mickiewicz
University [AMU]), I welcome you to the IV Forum EMR-PL organized under the auspices of
the Polish EMR Group. We all appreciate very much the hard work and organisational efforts of
our colleagues in Poznań, which have brought this Forum to fruition. On personal side, I am
pleased that this Forum is held at the Adam Mickiewicz University, since this is my Alma Mater.
Returning to AMU in 2015, after over 27 years living abroad and 10 years in Szczecin, I can
appreciate the tremendous developments, exemplified, e.g. by the Morasko campus. I believe
that this Forum may play an important role in enhancing the strength of the EMR research groups
in Poznań, which were, to a great extent, created due to the pioneering efforts led by the late Prof.
Jan Stankowski.
Continuing with the spirit of the 1st Forum in Rzeszów, 2
nd in Huciska, and 3
rd in
Kraków, this Forum is open to all participants involved in EMR basic research and applications.
The main aims are to bring together EMR (EPR/ESR & FMR/AFMR) spectroscopists working
in Poland as well as to promote and facilitate collaboration among the Polish EMR community. I
am confident that the scientific program of the IV Forum EMR-PL will satisfy most participants
and provide ample opportunities to meet fellow researchers and to discuss various topics of
interest.
For the first time we have invited as plenary speakers two eminent EMR researchers from
abroad: Prof. Hitoshi Ohta, President of the International EPR/ESR Society and Head of the
Molecular Photoscience Research Center at Kobe University, Japan and Prof. K. Lips, Vice-
President of the European Society for Quantum Solar Energy Conversion and Head of the
Energy Materials In-situ Laboratory Berlin, Germany. We are grateful for accepting our
invitation and hope that their participation will be beneficial to all colleagues.
I would also like to invite all participants, irrespective of their present status of
membership in the Polish EMR Group, to join us at the General Meeting (GM) of the Society, to
be held during the Forum. A whole range of topics of interest to the whole EMR community will
be discussed. Hence, your votes and opinions are of great importance as they may shape the
future course of events.
My sincere thanks go to all members of the Local Organising Committee, especially
Profs. Kempiński and Krzyminiewski, for their dedicated work to make the IV Forum EMR-PL a
successful meeting. Support from the Scientific Committee in nominating the invited speakers
and maintaining the high standard of this Forum is also much appreciated. I wish to express our
gratitude to all sponsors for their financial support: Institute of Molecular Physics, PAS; Faculty
of Physics, AMU; Committee of Physics of PAS; APVACUUM; Bruker Polska; Euro-Hel;
noviLET; Krio-Serwis; Cavipan. Thanks are due to all speakers and participants, who by their
attendance will help to make this Forum a great success.
I wish you all an enjoyable and stimulating experience at the Forum and in Poznań.
Thank you.
Czesław Rudowicz
Chairman, Polish EMR Group [established in Rzeszów, 2010]
Founder President, Asia-Pacific EPR/ESR Society [established in Hong Kong, 1997]
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Program IV FORUM EMR-PL
Monday, 27 June
8:00 - 9:30 Registration
9:30 - 9:50 Opening ceremony
9:50 Modern EMR techniques: new solutions, measurement techniques,
systems and equipment
Chairman: C. Rudowicz
9:50 - 10:35 Plenary lecture:
H. Ohta: Exotic Quantum Spin Systems Studied by Multi-Extreme THz EMR
10:35 - 11:05 Invited speaker:
T. Czechowski: New Methods in Electron Paramagnetic Resonance Imaging
Field
11:05 - 11:25 Oral presentation:
K. Tadyszak: Adaptive Modulation Amplitude Method in 2D Spectral-Spatial
EPR Imaging
11:25 - 11:40 Coffee Break
11:40 EMR in physics, chemistry and material research
Chairmen: H. Ohta, R. Fedaruk
11:40 - 12:10 Invited speaker:
N. Guskos: Magnetic Resonance and DC Magnetization Study of Phases in
FeVO4–Co3V2O8 System
12:10 - 12:30 Oral presentation:
V. D. Popowych: Ferromagnetic Resonance in CdTe:Cr Single Crystals
Containing Dopant-Related Macrodefects
12:30 - 12:50 Oral presentation:
T. Bodziony: Magnetic Study of Nanocrystalline TiB2,TiC, B4C Powders
Doped to AISI 316L Austentic Steel
12:50 - 13:10 Oral presentation:
R. Strzelczyk: FMR/EPR Study of Ferromagnetic Properties of Pristine and
Modified Graphene
13:10 - 14:30 Lunch
14:30 Quantum-chemical modeling in EMR spectroscopy and spectra
simulation
Chairman: J. Jezierska, S. Łoś
14:30 - 15:00 Invited speaker:
Z. Sojka: Molecular Interpretation of EPR Parameters – Computational
Spectroscopy Approaches
15:00 - 15:20 Oral presentation:
C. Rudowicz: Comparative Analysis of the Experimental and Theoretical
Zero Field Splitting and Zeeman Electronic Parameters for Fe2+
Ions in
FeX2∙4H2O (X = F, Cl, Br, I) and [Fe(H2O)6](NH4)2(SO4)2
15:20 - 15:40 Oral presentation:
M. Kozanecki: Effective Spin S~
= 2 Versus Fictitious S' = 1 Approach -
Conversions of the 2nd
-Rank Zero Field Splitting Parameters Measured by
High-Frequency EMR for Fe2+
Ions in Forsterite
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Tuesday, 28 June
9:45 EMR in physics, chemistry and material research
Chairmen: M. Komorowska, W. Kempiński
9:45 - 10:30 Plenary lecture:
K. Lips: Ultra-Sensitive in-Operando Detection and Imaging of
Paramagnetic Defects in Silicon Solar Cells
10:30 - 11:00 Invited speaker:
J. Jezierska: Isotropic And Anisotropic Spin-Spin Interactions In
Metallacycles With Single M-X-M Bridges
11:00 - 11:20 Oral presentation:
M. Witwicki: EPR and DFT Insight into Interaction between O-Semiquinone
Radicals and Metal Ions
11:20 - 11:40 Oral presentation:
K. Sobańska: Formation of Reactive Oxygen Species on the Amorphous
Nonredox Materials During Reaction With H2O2
11:40 - 12:00
Oral presentation:
B. V. Padlyak: Radiation-Induced Paramagnetic Centers in some Borate
Glasses
12:00 - 12:20 Coffee Break
12:20 EMR in biology and medicine
Chairman: K. Lips, Z. Sojka
12:20 - 12:50 Invited speaker:
M. Komorowska: Fatty Acids Binding Sites and Conformational Changes by
the Binding of them on Bovine Serum Albumin
12:50 - 13:20 Invited speaker:
R. Krzyminiewski: ESR investigation of functionalized magnetite
nanoparticles
13:20 - 13:40 Oral presentation:
M. Kurdziel: Application of Qualitative Standards to Interpretation of EPR
Spectra of Plant Material
13:40 - 14:00 Oral presentation:
Z. Matuszak: Electron Donor-Acceptor Properties of Melanin Studied by
EPR And Redox Potentiometry
14:00 - 15:30 Lunch
15:30 EMR in physics, chemistry and material research
Chairman: M. Augustyniak-Jabłokow, R. Krzyminiewski
15:30 - 16:00 Invited speaker:
S. Łoś: Graphene Oxide – EPR And Impedance New Interpretation
16:00 - 16:20 Oral presentation:
Z. Trybuła: Dielectric and EPR Studies on Fullerenes: C60 and C70
15:40 - 16:00 Oral presentation:
P. Pietrzyk: Insight into Electronic and Magnetic Structure Of Ni(II)-NO
Adduct inside the Channels of ZSM-5 Zeolite from Molecular Modeling, EPR
And HYSCORE Measurements
16:00 - 17:00 General Meeting of the Polish EMR Group
17:00 - 19:00 Poster session/ Get together party
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Wednesday, 29 June
9:45 Physical fundamentals and novel topics in EMR
Chairman: N. Guskos
9:45 - 10:30 Plenary lecture:
C. Rudowicz: Magnetic Transition-Metal and Rare-Earth Adatoms on
Surfaces – EMR Perspective
10:30 - 11:00 Invited speaker:
R. Fedaruk: The EPR Spectra of Bulk Anthracite under Strong Coupling of a
Spin Ensamble to Resonator
11:00 - 11:20 Oral presentation:
M. A. Augustyniak-Jabłokow: Interpretation of “Anomalous” Temperature
Dependencies of EPR Signal Intensity in Various Systems
11:20 - 11:40 Coffee Break
11:40 - 11:50 Poster Awards
11:50 - 13:10 Micro Orals
13:10 - 13:25 Closing ceremony
13:30 - 15:00 Lunch
16:20 - 16:40 Oral presentation:
M. Kuźma: Structural and Magnetic Order and Disorder in Metamagnetic
Shape Memory Alloys Ni2Mn1+xIn1-x
16:40 - 17:00 Oral presentation:
I. Stefaniuk: Electron Paramagnetic Resonance and Optical Study of
Ca4GdO(BO3)3 Single Crystals after Irradiation by Bismuth Ions
19:00 Conference Dinner – Działyński Palace
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Table of Contents
ORAL CONTRIBUTIONS 13
Plenary lecture
EXOTIC QUANTUM SPIN SYSTEMS STUDIED BY MULTI-EXTREME THZ EMR
H. Ohta 14
Invaited speaker
NEW METHODS IN ELECTRON PARAMAGNETIC RESONANCE IMAGING FIELD
T. Czechowski 15
Oral presentation
ADAPTIVE MODULATION AMPLITUDE METHOD IN 2D SPECTRAL-SPATIAL EPR IMAGING
K. Tadyszak 16
Invaited speaker
MAGNETIC RESONANCE AND DC MAGNETIZATION STUDY OF PHASES IN FeVO4–Co3V2O8
SYSTEM
N. Guskos 17
Oral presentation
FERROMAGNETIC RESONANCE IN CdTe:Cr SINGLE CRYSTALS CONTAINING DOPANT-RELATED
MACRODEFECTS
V.D. Popovych 18
Oral presentation
MAGNETIC STUDY OF NANOCRYSTALLINE TiB2,TiC, B4C POWDERS DOPED TO AISI 316L
AUSTENTIC STEEL
T. Bodziony 19
Oral presentation
FMR/EPR STUDY OF FERROMAGNETIC PROPERTIES OF PRISTINE AND MODIFIED GRAPHENE
R. Strzelczyk 20
Invaited speaker
MOLECULAR INTERPRETATION OF EPR PARAMETERS – COMPUTATIONAL SPECTROSCOPY
APPROACHES
Z. Sojka 21
Oral presentation
COMPARATIVE ANALYSIS OF THE EXPERIMENTAL AND THEORETICAL ZERO FIELD SPLITTING
AND ZEEMAN ELECTRONIC PARAMETERS FOR Fe2+
IONS IN FeX2∙4H2O (X = F, Cl, Br, I) AND
[Fe(H2O)6](NH4)2(SO4)2
C. Rudowicz 22
Oral presentation
EFFECTIVE SPIN �̃� = 2 VERSUS FICTITIOUS S' = 1 APPROACH - CONVERSIONS OF THE 2ND
-RANK
ZERO FIELD SPLITTING PARAMETERS MEASURED BY HIGH-FREQUENCY EMR FOR Fe2+
IONS IN
FORSTERITE
M. Kozanecki 23
Oral presentation
INSIGHT INTO ELECTRONIC AND MAGNETIC STRUCTURE OF NI(II)-NO ADDUCT INSIDE THE
CHANNELS OF ZSM-5 ZEOLITE FROM MOLECULAR MODELING, EPR AND HYSCORE
MEASUREMENTS
P. Pietrzyk 24
9
Plenary lecture
ULTRA-SENSITIVE IN-OPERANDO DETECTION AND IMAGING OF PARAMAGNETIC DEFECTS IN
SILICON SOLAR CELLS
K. Lips 25
Invaited speaker
ISOTROPIC AND ANISOTROPIC SPIN-SPIN INTERACTIONS IN METALLACYCLES WITH SINGLE M-
X-M BRIDGES
J. Jezierska 26
Oral presentation
EPR AND DFT INSIGHT INTO INTERACTION BETWEEN O-SEMIQUINONE RADICALS AND METAL
IONS
M. Witwicki 27
Oral presentation
FORMATION OF REACTIVE OXYGEN SPECIES ON THE AMORPHOUS NONREDOX MATERIALS
DURING REACTION WITH H2O2
K. Sobańska 28
Oral presentation
RADIATION-INDUCED PARAMAGNETIC CENTERS IN SOME BORATE GLASSES
B. V. Padlyak 29
Oral presentation
FATTY ACIDS BINDING SITES AND CONFORMATIONAL CHANGES BY THE BINDING OF THEM ON
BOVINE SERUM ALBUMIN
M. Komorowska 30
Invaited speaker
ESR INVESTIGATION OF FUNCTIONALIZED MAGNETITE NANOPARTICLES
R. Krzyminiewski 31
Oral presentation
APPLICATION OF QUALITATIVE STANDARDS TO INTERPRETATION OF EPR SPECTRA OF PLANT
MATERIAL
M. Kurdziel 32
Oral presentation
ELECTRON DONOR-ACCEPTOR PROPERTIES OF MELANIN STUDIED BY EPR AND REDOX
POTENTIOMETRY
Z. Matuszak 33
Invaited speaker
GRAPHENE OXIDE – EPR AND IMPEDANCE NEW INTERPRETATION
S. Łoś 34
Oral presentation
DIELECTRIC AND EPR STUDIES ON FULLERENES: C60 AND C70
Z. Trybuła 35
Oral presentation
STRUCTURAL AND MAGNETIC ORDER AND DISORDER IN METAMAGNETIC SHAPE MEMORY
ALLOYS Ni2Mn1+xIn1-x
M. Kuźma 36
Oral presentation
ELECTRON PARAMAGNETIC RESONANCE AND OPTICAL STUDY OF Ca4GdO(BO3)3 SINGLE
CRYSTALS AFTER IRRADIATION BY BISMUTH IONS
I. Stefaniuk 37
10
Plenary speaker
MAGNETIC TRANSITION-METAL AND RARE-EARTH ADATOMS ON SURFACES – EMR
PERSPECTIVE
C. Rudowicz 38
Invaited speaker
THE EPR SPECTRA OF BULK ANTHRACITE UNDER STRONG COUPLING OF A SPIN ENSEMBLE TO
RESONATOR
R. Fedaruk 39
Oral presentation
INTERPRETATION OF “ANOMALOUS” TEMPERATURE DEPENDENCIES OF EPR SIGNAL INTENSITY
IN VARIOUS SYSTEMS
M. A. Augustyniak-Jabłokow 40
POSTER CONTRIBUTIONS 41
Poster I
EUPHORBIA TURKESTANICA TANNINS – ANTIRADICAL ACTIVITY, INTERACTION WITH ALPHA-
HEMOLYSIN AND ERYTHROCYTES LIPIDS
M. Bitiucki 42
Poster II
MAGNETIC INVESTIGATIONS OF Nb6Sb3VO25
M. Bobrowska 43
Poster III
SPATIAL- AND SPECTRAL-SPATIAL IMAGING - AN APPLICATION TO EPRI OXIMETRY
A. Boś-Liedke 44
Poster IV
EMR SPECTRA OF ZNO THIN FILMS DOPED WITH HIGH CONCENTRACTION OF CO AND CR ON
QUARTZ AND SAPPHIRE SUBSTRATES
B. Cieniek 45
Poster V
EPR STUDY OF Cu-Mn-Zn SPINELS SUPPORTED ON DEALUMINATED HY(–Al) ZEOLITE
P. Decyk 46
Poster VI
FERROMAGNETIC RESONANCE IN NiCoMnIn LAYERS OBTAINED BY PULSED LASER DEPOSITION
Ł. Dubiel 47
Poster VII
WIDE TEMPERATURE RANGE SYSTEM FOR EPR MEASUREMENTS UP TO 1300 K
Z. J. Frączek 48
Poster VIII
MAGNETIC PROPERTIES OF STEEL BALLS INVESTIGATED BEFORE AND AFTER NITRIDING
PROCESS
H. Fuks 49
Poster IX
MONITORING OF PLATELET MEMBRANE FLUIDITY DURING DIALYSIS OF SHEEP
K. Gałecka 50
Poster X
SPIN LABELING STUDIES OF ERYTHROCYTES PROPERTIES IN VARICOSE VEINS PATIENTS
K. Gwoździński 51
11
Poster XI
RADIATION DEFECTS IN CALCITE AND THEIR INFLUENCE ON MECHANICAL PROPERTIES
Z. Kabacińska 52
Poster XII
EPR INVESTIGATIONS INTO FORMATION OF NITROSYL COMPLEXES OF PALLADIUM CATIONS IN
ZEOLITES Y AND ZSM-5
A. Krasowska 53
Poster XIII
EPR STUDY OF PARAMAGNETIC CENTERS ON A SURFACE OF MODIFIED NANODIAMONDS
A. Krupska 54
Poster XIV
EPR STUDY OF THE MAGNETIC PROPERTIES OF IRON OXIDE NANOPARTICLES IN HUMAN BLOOD
AND SERUM
T. Kubiak 55
Poster XV
OPTIMIZATION OF ANTIOXIDANT PROPERTIES OF WATER-IN-OIL AND OIL-IN-WATER CREAMS
WITH BILBERRY, CHOKEBERRY AND ELDERBERRY EXTRACTS BY ARTIFICIAL NEURAL
NETWORKS
K. Makarova 56
Poster XVI
HYPERFINE STRUCTURE OF VANADIUM IONS IN LIQUIDS AND SOLIDS
I. Mrówka 57
Poster XVII
SPECIFICITY OF FREE RADICAL-SCAVENGING PROPERTIES OF SUMAC TANNINS IN PROTECTION
OF ERYTHROCYTES AGAINST OXIDATIVE STRESS
E. Olchowik-Grabarek 58
Poster XVIII
MICROWAVE X-BAND RESONANCES IN DOPED Cd2Nb2O7 MONOCRYSTALS
A. Ostrowski 59
Poster XIX
POTENTIAL ROLE OF SUPEROXIDE ANION IN HOMOCYSTEINE-INDUCED FLUIDIZATION OF
PLATELET MEMBRANES – EVIDENCE FROM PRELIMINARY EPR MEASUREMENTS
A. Pieniążek 60
Poster XX
THEORETICAL INVESTIGATIONS OF THE SPIN HAMILTONIAN PARAMETERS AND THE LOCAL
STRUCTURE OF Co2+
IONS IN PbMoO4 CRYSTAL
D. Piwowarska 61
Poster XXI
THE STUDY OF FREE RADICALS IN THE ENRICHED PEAT OF SPENT OIL – EPR TECHNIQUE
B. Pytel 62
Poster XXII
FERROMAGNETIC RESONANCE STUDY OF HIGHLY CHROMIUM DOPED CdTe ALLOY
I. Rogalska 63
Poster XXIII
RELATION OF TOTAL POLYPHENOL AND FLAVONOID CONTENTS TO ANTI-RADICAL
PROPERTIES AND STABILITY OF TINCTURES OF GEISSOSPERMUM RETICULATUM:
CHEMOMETRIC ANALYSIS AND LAG PHASE EPR
J. J. Sajkowska-Kozielewicz 64
12
Poster XXIV
EMR DATA ON HIGH-SPIN Mn3+
(S = 2) IONS IN MnTPPCl COMPLEX MODELLED BY MICROSCOPIC
SPIN HAMILTONIAN APPROACH
K. Tadyszak 65
Poster XXV
MAGNETIC DEFECTS IN Nb2SbVO10
J. Typek 66
Poster XXVI
INTERACTION BETWEEN SPIN – LABELED Fe3O4 NANOPARTICLES AND HUMAN BLOOD STUDIED
BY EPR METHOD
K. Urbaniak 67
Poster XXVII
UV-INDUCED RADICALS IN STATINES – LIPID-LOWERING MEDICATIONS
M. Wencka 68
Poster XXVIII
Cu2+
DOPED MOLECULAR SIEVES FOR MONITORING STRUCTURAL CHANGES AND GUEST-HOST
INTERACTIONS
A. Zalewska 69
Poster XXIX
SPIN TRAP AND SPIN PROBE ESR FOR THE OPTIMIZATION OF ANTIOXIDANT PROPERTIES OF
HERBAL BATHING SALTS
K. Zawada 70
Poster XXX
EPR STUDIES OF THE FREE RADICAL SCAVENGING ACTIVITY OF SIMVASTATIN
M. Zdybel 71
PosterXXXI
THE INFLUENCE OF SIMVASTATIN ON FREE RADICALS IN HUMAN MELANOMA MALIGNUM
CELLS – EPR EXAMINATION
M. Zdybel 72
Poster XXXII
EPR/FMR STUDY OF nCoO/(1-n)ZnO (n=0.4, 0.5, 0.6 AND 0.7) NANOCOMPOSITES
G. Zolnierkiewicz 73
13
Oral contributions
14
IV FORUM EMR-PL 27-29.VI. 2016
Plenary lecture
EXOTIC QUANTUM SPIN SYSTEMS STUDIED BY MULTI-EXTREME THZ EMR
H. Ohta1,2
, S. Okubo1,2
, E. Ohmichi2, T. Sakurai
3, S. Hara
3, H. Takahashi
4
1 Molecular Photoscience Research Center, Kobe University, Kobe, 657-8501 Japan
2 Graduate School of Science, Kobe University, Kobe, 657-8501, Japan
3 Center for Support to Research and Education Activities, Kobe University, Kobe, 657-8501, Japan
4 Organization of Advanced Science and Technology, Kobe University, Kobe, 657-8501, Japan
Development of multi-extreme THz EMR is one of our main activities in Kobe. It
covers the frequency region between 0.03 and 7 THz using Gunn Oscillators, multipliers,
backward wave oscillators (BWO) and the optically pumped far-infrared (FIR) laser [1], the
temperature region between 1.8 and 300 K [1], the magnetic field region up to 55 T using the
pulsed magnetic field [1], and the pressure region up to 1.5 GPa using the transmission type
piston cylinder pressure cell made by NiCrAl alloy and ceramic piston parts [2]. Recently we
have extended the pressure region up to 2.7 GPa using the hybrid-type pressure cell [3]. The
hybrid-type pressure cell is the double layered cell which consists of NiCrAl alloy inner cell
and Cu-Be alloy outer cell. Moreover, we have also developed the highly sensitive
mechanically detected micro-cantilever ESR, which enables the measurements of micrometer
size sample [4] Very recently the micro-cantilever ESR measurements has been extended up to
1.1 THz, which is the world record for such mechanical detection of EMR.[5] As for the
longitudinal EMR measurement, we have also succeeded in the magnetization detected EMR
using SQUID (Superconducting Quantum Interference Device) magnetometer (SQUID EMR)
[6]. As applications of such multi-extreme EMR, we would like to refer to two topics. First is
the high field EMR study of the multiferroic substance YCrO3, which shows a ferroelectric
transition below TC = 470 K and an antiferromagnetic transition with a weak ferromagnetism
due to Dzyaloshinskii–Moriya (DM) interaction below TN = 140 K [7]. As we have extended
the AFMR measurement up to 35 T in the high field region and 0.722 THz at 1.9 K compared
to the previous one [8], we have found a new AFMR mode and unconventional behaviors.
Secondary the high pressure THz EMR results of Shastry-Sutherland model substance
SrCu2(BO3)2 single crystal up to 2 GPa at 2 K will be presented. Possible pressure induced
phase transition predicted by the theory [9] will be discussed.
References [1] H. Ohta et al., J. Low Temp. Phys. 2013, 170, 511.
[2] T. Sakurai et al., Rev. Sci. Inst. 2007, 78, 065107; T. Sakurai, J. Phys.: Conf. Series, 2010,
215, 012184.
[3] K. Fujimoto et al., Appl. Mag. Res. 2013, 44, 893; H. Ohta et al., J. Phys. Chem. B 2015,
119, 13755; T. Sakurai et al., J. Mag. Res., 2015, 259,108.
[4] H. Ohta et al., AIP Conf. Proceedings 2006, 850, 1643; E. Ohmichi et al., Rev. Sci.
Instrum. 2008, 79, 103903; E. Ohmichi et al., Rev. Sci. Instrum. 2009, 80, 013904; H. Ohta
and E. Ohmichi, Appl. Mag. Res. 2010, 37, 881; E. Ohmichi et al., J. Low Temp. Phys.
2010, 159, 276; Y. Tokuda et al., J. Phys.: Conf. Series 2012, 400, 032103; E. Ohmichi et
al., J. Mag. Res. 2013, 227, 9.
[5] H. Takahashi, E. Ohmichi, H. Ohta, Appl. Phys. Lett. 2015, 107, 182405.
[6] T. Sakurai et al., J. Phys.: Conf. Series 2011, 334, 012058; T. Sakurai et al., J. Mag. Res.
2012, 223, 41; T. Sakurai et al., J. Magnetics 2013, 18, 168.
[7] C. R. Serrao et al., Phys. Rev. B 2005, 72, 220101(R)/4.
[8] V.A. Sanina et al., Phys. Lett. 1970, 33A, 291.
[9] A. Koga and N. Kawakami, Phys. Rev. Lett. 2000, 84, 4461.
15
IV FORUM EMR-PL 27-29.VI. 2016
Invaited speaker
NEW METHODS IN ELECTRON PARAMAGNETIC RESONANCE IMAGING
FIELD
T. Czechowski1, M. Baranowski
2, W. Chlewicki
3, K. Jurga
2, P. Szczepanik
4, P. Szulc
4, K.
Tadyszak5, P. Kedzia
4, P. Malinowski
6, J. Jurga
4
1noviLET, Poznan, Poland.
2Adam Mickiewicz University, Department of Physics, Poznan, Poland.
3West Pomeranian University of Technology, Faculty of Electrical Engineering, Szczecin, Poland.
4Poznan University of Technology, Laboratory of EPR Tomography, Poznan, Poland.
5Adam Mickiewicz University, NanoBioMedical Centre, Poznan, Poland.
This presentation outlines a concept for fast spectral and spectral-spatial electron
paramagnetic resonance imaging (EPRI). We report on progress in shortening acquisition time,
increasing signal to noise ratio and image resolution towards the implementation novel
detection and signal analysis methods. We demonstrate that application of modern CW and
rapid scan EPR methods can provide unique insight into the EPRI field. The presented results
are based on experiments using rotated magnetic field gradient, adaptive method of choosing
modulation amplitude for each projection, multiharmonics analysis, high resolution
deconvolution and sinogram fitting procedures.
One of the method to reduce measurement time is combining rapid scan of Zeeman
magnetic field using high frequency sinusoidal modulation with simultaneously applied
magnetic field gradient, which orientation or amplitude are changed at low frequency. The
presented method allows to reduce the image acquisition time up to 10 ms for 2D spatial [1],
and 200ms for 2D spectral-spatial EPRI [2]. To improve the signal to noise ratio (SNR) of the
projections in CW EPR technique a more consciously selected modulation amplitude
parameter could be applying. In the case of the projections obtained by this adaptive
modulation method, the SNR was more constant (in all projections) than for the fixed
modulation amplitudes values.
References [1] T. Czechowski, W. Chlewicki, M. Baranowski, K. Jurga, P. Szczepanik, P. Szulc, K. Tadyszak, P. Kedzia, M.
Szostak, P. Malinowski, S. Wosinski, W. Prukala, J. Jurga, J. Magn. Res. 248 126 – 130, (2014).
[2] T. Czechowski, W. Chlewicki, M. Baranowski, K. Jurga, P. Szczepanik, P. Szulc, P. Kedzia, M. Szostak, P.
Malinowski, S. Wosinski, W. Prukala, J. Jurga, J. Magn. Res.243, 1 – 7, (2014).
16
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
ADAPTIVE MODULATION AMPLITUDE METHOD IN 2D SPECTRAL-SPATIAL
EPR IMAGING
T. Czechowski*1,5
, Z. Kabacińska1,6
, A. Samolej4, M. Baranowski
3,5, A. Boś-Liedke
6, W.
Chlewicki2,5
, M. Jancelewicz1, J. Jurga
4,5, K. Tadyszak
1**
1 NanoBioMedical Centre, Adam Mickiewicz University, ul. Umultowska 85, PL 61614 Poznań, Poland
2 Faculty of Electrical Engineering, West Pomeranian University of Technology, al. Piastów 17, 70-310 Szczecin,
Poland 3 Physics Department, Faculty of Physics, Adam Mickiewicz University, ul. Umultowska 85, PL 61614 Poznań,
Poland 4 Laboratory of EPR Tomography, Poznan University of Technology, ul. Piotrowo 3, PL 60965 Poznań, Poland
5 noviLET, ul. Romana Maya 1, PL 61371 Poznań, Poland
6 Medical Physics Department, Faculty of Physics, Adam Mickiewicz University, ul. Umultowska 14, PL 61614
Poznań, Poland
A study concerning the image quality in Electron Paramagnetic Resonance Imaging
(EPRI) in 2D spectral-spatial (2D SSI) experiments is presented. The aim of the measurements
was to improve the signal to noise ratio (SNR) of the projections by applying a more
consciously selected modulation amplitude parameter. Data was gathered by applying three
constant and one adaptive modulation amplitude. Three modulation amplitude values were
used in this experiment, leading to undermodulated, partially overmodulated and fully
overmodulated projections. The advantages of the adaptive method of choosing modulation
amplitude for each projection were demonstrated in the study performed on a phantom
containing four tubes of LiPc and TCNQ, characterized by a different peak to peak linewidth
and spin concentration. In the case of the projections obtained by the adaptive modulation
method, the SNR was more constant (in all projections) than for the fixed modulation
amplitudes values. The linewidths obtained from 2D SSI were in the best agreement with the
values expected for the phantom used for the adaptive modulation amplitude method.
17
IV FORUM EMR-PL 27-29.VI. 2016
Invaited speaker
MAGNETIC RESONANCE AND DC MAGNETIZATION STUDY OF PHASES IN
FeVO4–Co3V2O8 SYSTEM
N. Guskos1, G. Zolnierkiewicz
1, M. Pilarska
1, J. Typek
1, A. Blonska-Tabero
2
1Department of Physics, West Pomeranian University of Technology, Al. Piastow 48, 70-311 Szczecin, Poland
2Department of Inorganic and Analytical Chemistry, West Pomeranian University of Technology, Al. Piastow 42,
70-065 Szczecin, Poland
Magnetic properties of four samples obtained from reactions between FeVO4 and
Co3V2O8 have been investigated byusing magnetic resonance spectroscopy and dc
magnetization (in ZF and ZFC modes) techniques. At room temperature all parameters of
magnetic resonance spectra strongly depended on thermal annealing of the prepared samples
(first four samples listed in Table 1 in Ref. 1).The composition of initialmixtures, the heating
conditions and the results of the XRD analysis of the obtained samples were presented in Ref.
2.From dc magnetization measurements it was concluded the formation of superparamagnetic
and antiferromagnetic phases with the blocking temperature and the Curie-Weiss temperature
in the low temperatures range. These two parameters were strongly dependent upon the thermal
treatment conditions of synthesised samples. At low and high temperatures the magnetic
hysteresis was observed and its parameters were dependent upon the method of thermal
treatment. The morphology of the investigated samples consisted of large magnetic
agglomerates built up from nanoclusters.This favours the possibility of formation of the
superparamagnetic phase. From the obtainedtemperature dependence of magnetic resonance
parameters it was concluded that the observed resonance line was derived from the magnetic
nanoclusters.
References 1. N. Guskos, G. Zolnierkiewicz, J. Typek, and A. Blonska-Tabero, Physica B 406, 2163 (2011).
2. A. Blonska-Tabero, M. Kurzawa, J. Therm. Anal. Calorimetry 88, 33 (2007).
18
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
FERROMAGNETIC RESONANCE IN CdTe:Cr SINGLE CRYSTALS CONTAINING
DOPANT-RELATED MACRODEFECTS
V.D. Popovych1, M. Kuźma
2, N. Skop
2, I. Stefaniuk
3, B. Cieniek
3
1Department of Machine Science and Fundamental Technologies, Ivan Franko Drogobych State Pedagogical
University, 24 Ivan Franko str., 82100 Drogobych, Ukraine 2Faculty of Mathematics and Natural Sciences, Department of Biophysics,
University of Rzeszow, Pigonia 1, 35-959 Rzeszow, Poland 3Faculty of Mathematics and Natural Sciences, Department of Experimental Physics,
University of Rzeszow, Pigonia 1, 35-959 Rzeszow, Poland
The investigated CdTe:Cr single crystals were grown by the modified PVT method
from pre-synthesized charge with 2.5 and 5 at.% of Cr nominal content [1]. A number of
macrodefects were revealed by SEM patterning and EDX analysis in the crystals, both in the
form of sub-µm near-isometric particles and arranged sets of thin (less than 1 µm) polygons.
They were identified by HAADF analysis and HRTEM studies as Cr3Te4 precipitates, which
are formed during post-grown cooling due to poor solubility of Cr in CdTe [2].
Fig.1. Angular dependence of FMR spectrum of the CdTe:Cr single crystal at 300 K. The insert shows EPR
spectrum of the crystal at 350K.
Magnetic properties of the crystals were measured by EPR method using 9.43 GHz X-band
Bruker FT-EPR spectrometer ELEXSYS E580. Magnetic resonance spectra of the samples at
room and at lower temperatures are complex; its constituent lines exhibit strong angular and
temperature dependences (Fig.1). The resonance fields of the lines lies in the wide range of
magnetic field (100 – 450mT). At particular orientation of the samples in respect to the applied
field the shift of some lines to very high fields (500 – 650 mT) is observed. At higher
temperatures the spectrum is much simpler and at 350 K consists of only one Gaussian-like
line, which is attributed to the paramagnetic state of the sample (insert in Fig.1). To understand
the complex structure of the obtained spectra at room temperature and their angular
dependences, we have taken into account the contribution of ferromagnetic Cr3Te4 phase in the
form of oriented platelets embedded into CdTe:Cr matrix along its {111} planes. At room and
at lower temperatures the spectra can be described by the FMR formalism.
References [1] V.D. Popovych, P. Sagan, M. Bester, B. Cieniek, M. Kuzma, J. Cryst. Growth 426 (2015) 1733.
[2] V.D. Popovych, P.Sagan. Acta Physica Polonica, A 129 (2016) 49.
19
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
MAGNETIC STUDY OF NANOCRYSTALLINE TiB2,TiC, B4C POWDERS DOPED
TO AISI 316L AUSTENTIC STEEL
T. Bodziony 1
, S. M. Kaczmarek1, A. Biedunkiewicz
2, G. Leniec
1, P. Figiel
2
1 Institute of Physics, West Pomeranian University of Technology, Al. Piastów 17,
70-310 Szczecin, Poland 2 West Pomeranian University of Technology, Al. Piastów 17,
70-310 Szczecin, Poland
The results of the EPR and magnetic susceptibility investigations of nanocrystalline
TiB2,TiC, B4C powders (3%, 5%, 7%) doped to AISI 316L austenitic steel have been
analyzed. The nanocrystalline materials offer unique chemical, structural, electrical, and
magnetic properties with wide range of potential applications. The tested five composite
samples, marked as samples 7-9, contain a number of crystalline and magnetic phases in
different proportions. The results of the EPR and magnetic susceptibility measurements of the
composites are presented for the first time. The EPR spectra are recorded from helium up to
room temperature. They reveal a structure originating from several different complex magnetic
centres. The changes of the total intensity of EPR spectra versus temperature are deeply
analysed. The temperature dependence of the total intensity of the EPR spectra of the
investigated composites reveals different magnetic phenomena like paramagnetism, ferro-
(and/or) antiferromagentism and superparamagnetism (see Fig 1). The conclusions resulting
from the EPR measurements has been verified by magnetic susceptibility measurements.
Magnetic properties of the TiB2,TiC, B4C powders doped to AISI steel may play important role
in further, possible applications many of the composite systems
Fig. 1. Temperature dependences of the total intensity for few sample AISI 316L + TiB2,TiC, B4C (7, 8, 9)
and comparison of EPR and magnetic susceptibility measurements for a sample No. 9
20
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
FMR/EPR STUDY OF FERROMAGNETIC PROPERTIES OF PRISTINE AND
MODIFIED GRAPHENE
R. Strzelczyk1, M.A. Augustyniak-Jabłokow
1, M. Maćkowiak
1
1 Institute of Molecular Physics, Polish Academy of Sciences, Poznan, Poland
Theoretical predictions concerning 1D ferromagnetic order on the zig-zag edges of pristine
graphene[1] and 2D surface ferromagnetism in modified graphenes[2] has been reported in
literature. But published experimental results often show different magnitudes and temperature
dependences of these effects. This arises most likely from mismatch between relatively weak
response of the studied materials (small samples) and typical magnetometric or SQUID
measurements.
Very promising alternative present Ferromagnetic Resonance registered with Electron
Paramagnetic Resonance spectrometer. In EPR intensity of recorded signal is directly
proportional to magnetic susceptibility. Even though we cannot obtain absolute value of
susceptibility it allows us to study its temperature dependences. In addition we can analyze
separately different magnetic contributions making up total sample response.
In this report we show results of our FMR/EPR study of ferromagnetic ordering existing in
graphene and some of its derivatives. Furthermore, we determine proper conditions of its
occurrence.
Fig.1 FMR/EPR spectra of pristine graphene, graphene oxide and hydrogenated graphene registered each
at temperature of 4K.
References
[1] O. Yazyev, M. Katnelson, Phys. Rev. Lett. 100 (2008)
[2] D. Soriano, F. Muñoz-Rojas, J. Fernández-Rossier , J.J. Palacios, , Phys. Rev. B 81 (2010)
21
IV FORUM EMR-PL 27-29.VI. 2016
Invaited speaker
MOLECULAR INTERPRETATION OF EPR PARAMETERS – COMPUTATIONAL
SPECTROSCOPY APPROACHES
Z. Sojka1, P. Pietrzyk
1
1 Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow, Poland
Electronic properties and reactivity of nanostructured oxide and metallozeolite systems
are intrinsically related with their low dimensionality, reduced size. The resultant inherent
heterogeneity of such systems gives rise to low symmetry phenomena and pronounced
speciation of the paramagnetic surface species, leading often to complicated multi-component
powder CW-EPR spectra. This severely restrains recognition of individual spectral features
since the information is often unevenly distributed over broad spectral range. As a
consequence, much of useful chemical data about the investigated system can only be
recovered with the help of advanced computer analysis of the EPR spectra supported by state
of the art quantum chemical calculations of their parameters (computational spectroscopy
approach).
While analyzing EPR spectra it is often difficult to directly relate the experimentally
obtained spin Hamiltonian (sH) parameters, such as g-tensors, hyperfine (A) or fine structure
(D) tensors to molecular structure. This is especially valid for complex spectra of low
symmetry, where traditional methods of analysis based on ligand field (LFT) or angular
overlap methods (AOM) suffer from the problem of over-parameterization, despite their
undeniable merit. Currently available quantum chemical methods for calculations of EPR
parameters can, however, be very helpful to correlate experimental data with structural
information in a nearly quantitative way. Computational EPR spectroscopy is rapidly
expanding from a highly specialized research area of quantum chemistry into a versatile tool of
broad academic service, capable of reliable prediction of sH parameters and related properties
[1]. In addition, it may provide crucial missing information for their in-depth interpretation in
terms of assignment of the observed magnetic transitions, insight into their molecular nature,
structure, discrimination between alternative structural hypotheses, and assessment of the
influence of dynamical and environmental effects.
In this contribution a short outline of the spin Hamiltonian parameters and their
quantum-chemical computation methods will be provided. The applicability of principal
calculation schemes based on density functional theory (DFT) and their usefulness will be
demonstrated on the basis of selected examples. They include transition metal complexes and
their adducts with reagent molecules inside the zeolite channels. Such approach was used for
investigation of changes in the electron and spin states taking place during the interaction of
small molecules like O2 and CO with transition metals of various electron configuration (Co,
Ni, Cu i) encaged in zeolites The results provided not only an in-depth insight into the
molecular nature of the g and A tensors of the examined systems, but also allowed to account
for noncoincidence of axes, spin polarization effects as well as structure sensitivity of the
extracted magnetic parameters.
References [1] P. Pietrzyk, K. Podolska, Z. Sojka, Molecular interpretation of EPR parameters – computational spectroscopy
approaches, in: B.C. Gilbert, D.M. Murphy, V. Chechik (Eds.), Specialist Periodical Reports - Electron
Paramagnetic Resonance, RSC Publishing, (2013) pp. 264-311.
22
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
COMPARATIVE ANALYSIS OF THE EXPERIMENTAL AND THEORETICAL
ZERO FIELD SPLITTING AND ZEEMAN ELECTRONIC PARAMETERS FOR Fe2+
IONS IN FeX2∙4H2O (X = F, Cl, Br, I) AND [Fe(H2O)6](NH4)2(SO4)2
M. Zając1, C. Rudowicz
2,3
1 Institute of Physics, West Pomeranian University of Technology, Al. Piastów 17, 70–310 Szczecin, Poland
2Faculty of Chemistry, A. Mickiewicz University (AMU), Umultowska 89B, 61-614 Poznań, Poland
3 Visiting Professor (AMU); On leave of absence from: Institute of Physics, West Pomeranian University of
Technology Szczecin, Al. Piastów 17, 70-310 Szczecin, Poland
The spin Hamiltonian (SH) parameters, including the zero field splitting (ZFS) and Zeeman
electronic (Ze) parameters [1, 2], have recently been modeled for Fe2+
ions in FeCl2∙4H2O and
FeF24H2O crystals, which exhibit similar crystal structure [3]. High-magnetic field and high-
frequency EMR (HMF-EMR) techniques, for references, see, e.g. [4, 5] provide nowadays
more reliable experimental ZFS and Ze parameter sets for 3d4 and 3d
6 (S = 2) ions, e.g. Fe
2+,
Mn3+
, and Cr2+
, which usually exhibit large and very large ZFS [3, 6]. Similar modeling, using
the package MSH/VBA [7, 8] is now carried out for [Fe(H2O)6](NH4)2(SO4)2 (FASH) [9-11].
The microscopic SH (MSH) approach incorporates MSH expressions for the ZFS and Ze
parameters up to fourth-order perturbation theory suitable for of 3d4 and 3d
6 ions with spin S =
2 at orthorhombic and tetragonal symmetry sites in crystals, which exhibit an orbital singlet
ground state arising from the ground 5D multiplet [7, 8].
The available data on the ground state and excited orbital states with the respective energy
levels determined or adopted for Fe2+
(S = 2) ions in FASH together with the spin-orbit
coupling (SOC) constants: c (in crystal), 0 (free ion), and the orbital reduction (or covalency)
factor defined as: c = k 0 are surveyed to obtain input for MSH/VBA calculations.
Experimental values of the ZFS parameters and energies determined for Fe2+
ions in FASH [9-
11] are reanalyzed in view of our modeling results and compared with those obtained for
FeX2∙4H2O (X = F, Cl, Br, I) compounds [3]. Investigations of the role of the fourth-rank ZFS
terms existing for S~
= 2 [1,2], which are often omitted in experimental studies, and the spin-
spin interaction contributions to the second- and fourth-rank ZFSPs are is now under progress.
Illustrative preliminary results will be presented.
Acknowledgements
This work was partially supported by the research grant # DEC-2012/04/M/ST3/00817
from the Polish National Science Center. One of us (MZ) is grateful to the Institute of Physics,
West Pomeranian University of Technology in Szczecin, for a PhD scholarship.
References [1] C. Rudowicz, M. Karbowiak, Coord. Chem. Rev. 287 (2015) 28.
[2] C. Rudowicz, S.K. Misra, Appl. Spectrosc. Rev. 36 (2001) 11.
[3] M. Zając, I. E. Lipiński, C. Rudowicz, J. Magn. Mag. Mat., 401 (2016) 1068.
[4] T. Sakurai, K. Fujimoto, R. Goto, S. Okubo, H. Ohta, Y. Uwatoko, J. Magn. Reson. 223 (2012) 41.
[5] J. Telser, J. Krzystek, A. Ozarowski, J. Biol. Inorg. Chem. 19 (2014) 297.
[6] C. Rudowicz, H.W.F. Sung, J. Phys. Soc. Japan 72 Supplement B (2003) 61.
[7] C. Rudowicz, H.W.F. Sung, Physica B 337 (2003) 204.
[8] C. Rudowicz, H.W.F. Sung, Manual for the Package MSH/VBA, unpublished (2004).
[9] J. C. Gill, P.A. Ivey, J. Phys. C: Solid State Phys. 7 (1974) 1536.
[10] R. Doerfler, et al., J. Phys. C: Solid State Phys. 19 (1986) 3005.
[11] J. Telser, et al., Magn. Reson. Chem. 43 (2005) S130.
23
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
EFFECTIVE SPIN S~
= 2 VERSUS FICTITIOUS S' = 1 APPROACH - CONVERSIONS
OF THE 2ND
-RANK ZERO FIELD SPLITTING PARAMETERS MEASURED BY
HIGH-FREQUENCY EMR FOR Fe2+
IONS IN FORSTERITE
M. Kozanecki1, C. Rudowicz
2,3
1 Faculty of Chemistry, A. Mickiewicz University (AMU), Umultowska 89B, 61-614 Poznań, Poland
2 Visiting Professor: Faculty of Chemistry, A. Mickiewicz University, Poznań, Poland
3 On leave of absence from: Institute of Physics, West Pomeranian University of Technology Szczecin, Poland
Electron magnetic resonance (EMR) determination of the spin Hamiltonian parameters
for Fe2+
ions in natural and synthetic forsterite (Mg2SiO4) by Shakurov et al. [1] has been
hindered by several factors. The wide-band EMR spectrometer covered a limited frequency
region of = 65 to 850 GHz, hence only three transitions were detected in the temperature
range of 4.2 - 15 K in the magnetic field up to 9.5 kG. Importantly, these three transitions have
been described supposing that, quote [1]: 'the system of energy levels has an effective spin S =
1' instead of the effective spin S~
= 2 [2-4] most likely expected for Fe2+
ions in low symmetry
sites, see, e.g. [5].
Our analysis of the EMR data [1] reveals that the 'spin' value S = 1 has been assigned for
Fe2+
in Mg2SiO4 only due to experimental limitations, whereas the approach [1] represents, in
fact, the fictitious spin S' = 1 arising from the effective spin S~
= 2 states [2-4]. The axial (D)
and rhombic (E) second-rank zero field splitting (ZFS) parameters (ZFSPs) [2-4], obtained by
fitting the experimental EMR data using spin Hamiltonian with spin S = 1 [1], cannot be
directly compared with D and E ( S~
= 2) available in literature for Fe2+
ions [5,7]. To enable
direct comparison of (D', E') [1] and (D, E) [5,7], appropriate conversion relations have been
derived for various combinations of the possible energy level schemes for the spin S~
= 2 and
S' = 1. Illustrative preliminary results of appropriate conversions of the 2nd
-rank ZFSPs
measured by high-frequency EMR for Fe2+
in natural and synthetic forsterite [1] will be
presented. Detailed results and full analysis are provided in [6]. Investigation of the role of the
fourth-rank ZFS terms, which must be taken into account for spin S~
= 2 [2-4] is now in
progress. The results of the extended calculations will be given elsewhere.
Acknowledgments CZR acknowledges the Polish National Science Center research grant DEC-
2012/04/M/ST3/ 00817; MK is grateful to the Faculty of Chemistry, A. Mickiewicz University,
for a PhD scholarship.
References [1] G.S. Shakurov, T.A. Shcherbakova, V.A. Shustov, Appl. Magn. Reson. 40 (2011) 135.
[2] C. Rudowicz, M. Karbowiak, Coord. Chem. Rev. 287 (2015) 28.
[3] C. Rudowicz, Magn. Res. Rev. 13 (1987) 1.
[4] C. Rudowicz, S.K. Misra, Appl. Spectrosc. Rev. 36 (2001) 11.
[5] C. Rudowicz, H.W.F. Sung, J. Phys. Soc. Japan 72 Supplement B (2003) 61.
[6] M. Kozanecki, C. Rudowicz, in preparation (2016).
[7] M. Zając, I. E. Lipiński, and C. Rudowicz, J. Magn. Mag. Mat. 401 (2016) 1068.
24
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
INSIGHT INTO ELECTRONIC AND MAGNETIC STRUCTURE OF NI(II)-NO
ADDUCT INSIDE THE CHANNELS OF ZSM-5 ZEOLITE FROM MOLECULAR
MODELING, EPR AND HYSCORE MEASUREMENTS
P. Pietrzyk1, K. Podolska-Serafin
1, T. Mazur
1, M. Radoń
1, M. Chiesa
2, Z. Sojka
1
1 Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow, Poland
2 Dipartimento di Chimica, Università di Torino, via P. Giuria 7, 10125, Torino, Italy
The paramagnetic mononuclear nickel adducts with small molecules NiI/II
–XY are the
key species implicated in various important homo- and heterogeneous catalytic systems.
Incorporation of these species into the channels of zeolites allows for their stabilization,
dilution, and magnetic separation, which is beneficial from the point of view of EPR studies.
For an in-depth understanding of the fundamental chemistry of the Ni–XY units, a detailed
atomic level description of the electronic and magnetic structure of these species is of a great
cognitive value. In case where XY molecule is a non-innocent ligand, electronic structure of
the adduct results from complicated, spin and charge flow channels [1] (the case of O2
molecule), or magnetic (ferro- or antiferromagnetic) couplings as in the present case of NO.
Herein, we report the results of CW-EPR and pulsed HYSCORE spectroscopies (Fig. 1a)
corroborated by quantum chemical investigations (DFT, CASSCF) of the Ni(II)–NO adducts
inside the channels of zeolite ZSM-5. Identification of the adsorption adduct was assured by
means of IR, EPR, and HYSORE methods allowing for extraction of g tensor and 14
N
hyperfine tensor parameters, as well as 27
Al quadrupole couplings due to zeolite backbone.
CASSCF calculations showed that the dominant contribution (87%) to the electronic wave
function results from the following configuration |(dxy)2(dxz)
2(dyz)
2(dz
2)(dx
2-y
2)(x
*)0(y
*)|
(tantamount to Ni(II, S = 1) + NO (0, S = 1/2) system). It indicated that the resulting magnetic
properties results from antiferromagnetic coupling between two open shell subsystems: Ni(II)
and NO (Fig. 1b).
Fig. 1. a) HYSCORE spectrum and its simulation for Ni(II)–NO adduct inside ZSM-5 zeolite and b) DFT
optimized cluster showing structure of Ni(II)–NO along with the spin density contour in broken symmetry
state (antiferromagnetic coupling between Ni(II) and NO is shown).
Acknowledgement
This work was financially supported by National Science Center Poland based on the decision
no. DEC-2013/11/D/ST4/02838.
References [1] P. Pietrzyk, K. Podolska, T. Mazur and Z. Sojka, J. Am. Chem. Soc., 133 (2011) 19931.
25
IV FORUM EMR-PL 27-29.VI. 2016
Plenary lecture
ULTRA-SENSITIVE IN-OPERANDO DETECTION AND IMAGING OF
PARAMAGNETIC DEFECTS IN SILICON SOLAR CELLS
K. Lips1, A. Schnegg
1, W. Akthar
1, J. Möser
1, I. Katz
2, A. Blank
2 C. Meier
3, J. Behrends
3, J.
Anders4
1 Berlin Joint EPR Lab, Helmholtz Zentrum Berlin für Materialien und Energie, Germany
2 Schulich Faculty of Chemistry, Technion, Israel
3 Berlin Joint EPR Lab, Fachbereich Physik, Freie Universität Berlin, Germany
4 Electrical Engineering, Universität Ulm, Germany
Almost 90% of all installed photovoltaic (PV) modules are fabricated using wafer-
based and thin-film silicon technology. The technology has reached a mature stage and current
generation costs of clearly below 0.1US$/kWh are reached. Further cost reduction can only be
achieved by further increasing module efficiency. The current efficiency record for silicon
solar cells is 26.6 % and was made possible due to excellent passivation and electrical
properties of the only 3-10 nm thin amorphous silicon (a-Si:H) layer that forms a charge
selective heterocontact with the crystalline silicon (c-Si) absorber. This then replaces the
classical silicon homo-pn junction that is achieved through phosphorus and boron doping of c-
Si. Despite the enormous success of this silicon heterojunction solar cell many open question
remain about the stability as well as the nature of the defect states of the thin a-Si:H contact
layer. Most of these defects are paramagnetic and are induced by are induced by compositional
and material disorder. These paramagnetic defects act as charge-carrier traps and
recombination centers. However, fully processed high efficiency PV devices with complex
morphologies typically do not exhibit enough paramagnetic states to be observed by EPR.
However, due to the weak spin-orbit coupling in silicon these defects can induce spin-
dependent charge carrier transport and recombination which can be detected with many orders
of magnitude higher sensitivity then EPR in pulsed and cw electrically detected magnetic
resonance experiments (pEDMR and cwEDMR, respectively).
After a short review of the status of PV technology, we will introduce the EDMR technique
and discuss the potential of combined EPR/EDMR for the study of intrinsic and light-induced
defects (LID) in a-Si:H materials [1,2] and heterojunction solar cells [3]. Structural information
obtained from pulsed multi-frequency EPR is complemented by cw and pEDMR ranging from
X-band up to 263 GHz. Benefiting from the increased resolution of multi-frequency EDMR
and the possibility to coherently manipulate coupled spins by pulsed EDMR excitation
schemes [4], a complete picture of charge carrier transport and recombination in silicon
materials and solar cells can be achieved. In addition, we will demonstrate how pEDMR in
combination with pulsed field gradients [5] provide in operando spatially resolved defect maps
of solar cells. An outlook to fascinating new applications of pEDMR using EPR-on-a-chip
concepts will be given.
References 1. M. Fehr, et al., Phys. Rev. Lett., 2014, 112, 066403
2. M. Fehr, et al., Phys. Rev B, 2011, 84, 245203/1-1
3. B.M. George, et al., Phys. Rev. Lett., 2013, 110(13), 136803
4. A. Schnegg, et al., PCCP, 2012, 14 (42), 14418-38
5. I. Katz, et al. Journal of Magnetic Resonance 251 (2015) 26–35
26
IV FORUM EMR-PL 27-29.VI. 2016
Schematic presentation of cationic
complexes [M2(μ-X)(μ-Lm)2]3+, R=H
[M2(μ-X)(μ-Lm*)2]3+,R=CH3
Invaited speaker
ISOTROPIC AND ANISOTROPIC SPIN-SPIN INTERACTIONS IN
METALLACYCLES WITH SINGLE M-X-M BRIDGES
J. Jezierska1, A. Ozarowski
2, D. L. Reger
3
1Faculty of Chemistry, Wroclaw University, Wroclaw, Poland
2National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA.
3Department of Chemistry and Biochemistry, University of South Carolina, Columbia,
South Carolina, USA.
Two ligands composed of two
bis(pyrazolyl)methane units linked by a m-substituted
arene spacer; bis[bis(1-pyrazolyl)methyl]benzene, (Lm
with R=H) and m-bis[bis(3,5-dimethyl-1-pyrazolyl)-
ethyl]benzene, (Lm* with R=CH3), have become a
basis for the syntheses [1-4] of cationic binuclear
metallacycles (see Scheme) in which two metal(II)
ions (M) are held in close proximity by single M-X-M
bridges. It was shown by X-ray crystal studies that the
bulky Lm* ligand rigorously enforces the linearity of
the bridging group, while Lm allows formation of the
bent bridges.
In this presentation we intend to overview the
magnetic and EPR properties of 3d transition metal
complexes shown in the Scheme by taking into
account the effects induced by:
a) bridges X = F−, Cl
−, Br
−, OH
− in the complexes with M=CuII and Lm* [1]
b) metal ions M = MnII, FeII , CoII , NiII , CuII in the complexes with X = F− and Lm* [2]
c) ligands Lm and Lm* in the complexes with M = CuII and X = OH− [3] or CN
− (μ-1,2
bridge) or N3− (μ-1,1 bridge) [4] as well as with M = CoII and X = OH
− [3].
It is noteworthy that when the molar ratio NiII : Lm = 4 : 2 was used in the synthesis the
tetranuclear cubane-core-hydroxide-bridged cationic complex [Ni4(μ3-OH)4(μ-Lm)2]+4
was
formed, with S=4 ground state [5].
The magnetic properties of the complexes, reflected in the temperature dependence of
magnetic moments, were analyzed in terms of the isotropic spin-spin magnetic interactions
(H = -JS1S2). The anisotropic spin-spin interactions (H = S1DS2), causing splitting of S>1/2
spin states in zero magnetic field, were measured by EPR at microwave frequencies 9 - 420
GHz and at various temperatures.
DFT calculations allowed to predict the efficiency and pathways of the isotropic spin-spin
interactions ("broken symmetry") illustrating the nature of metal magnetic orbitals in the
dinuclear complexes and tetranuclear cubane with metal ions in a distorted trigonal-bipyramid
and octahedron, respectively.
References
[1] D. L. Reger, A. E. Pascui, M. D. Smith, J. Jezierska, A. Ożarowski, Inorg. Chem., 2012, 51, 7966
[2] D. L. Reger, A. E. Pascui, M. D. Smith, J. Jezierska, A.Ożarowski, Inorg. Chem., 2012, 51, 11820
[3] D. L. Reger., A. E. Pascui, E. Foley, M. D. Smith, J. Jezierska, A. Ożarowski, Inorg. Chem., 2014, 53, 1975.
[4] D. L. Reger., A. E. Pascui, E. Foley, M. D. Smith, J. Jezierska, A. Ożarowski, Inorg. Chem., 2015, 54, 1487
[5] D. L. Reger., A. E. Pascui, P. J. Pellechia, M. D. Smith, J. Jezierska, A. Ożarowski, Inorg. Chem., 2014, 53,
4325
27
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
EPR AND DFT INSIGHT INTO INTERACTION BETWEEN O-SEMIQUINONE
RADICALS AND METAL IONS
M. Witwicki1, M. Jerzykiewicz
1, J. Jezierska
1, A. Ozarowski
2
1 Faculty of Chemistry, Wrocław Uniwersity, ul. . F. Joliot-Curie 14, 50-383 Wrocław, Poland
2 National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Drive,
Tallahassee, FL 32310, USA
Semiquinones are organic radicals being the intermediate form in the redox equilibrium
between quinones and hydroquinones. These radicals are present in all life forms as they act as
electron-transfer agents in the mitochondrial respiratory chain and in the reaction centres of
bacterial and plant photosynthesis [1,2]. Moreover, they are indigenous to natural polyphenols
(e. g. humic acids, tannins, lignin) [3,4]. o-Semiquinones are known to possess chelating ability
towards metal ions [5,6], which is particularly important for the activation of electron transfer
through interaction with cations acting as Lewis acids [6]. In this work EPR spectroscopy and
density functional theory (DFT) were used to elucidate the interaction between o-semiquinone
radicals and various diamagnetic metal ions: Mg2+
, Ca2+
, Hg2+
and Pb2+
[7-11]. The effect of
complexation on the molecular and electronic structures of the radicals were established and
correlated with the g tensor.
Fig. 1. EPR spectrum, DFT-predicted molecular structure and the singly occupied molecular orbitals of the
o-semiquinone – Hg(II) complex
References [1] S. Ohashi et al., Photosynth. Res. 104, (2010) 305.
[2] J. Barber, Chem. Soc. Rev. 38, (2009) 185.
[3] N. Senesi, Application of Electron Spin Resonance (ESR) Spectroscopy in Soil Chemistry, in B. A. Stewart
(Ed.), Advances in Soil Science Volume 14, Springer-Verlag, New York, (1990) 77-130.
[4] C. Bahrle, T. U. Nick, M. Bennati, G. Jeschke, F. Vogel, J. Phys. Chem. A 119, (2015) 6475.
[5] K.E. Vostrikova, Coord. Chem. Rev. 252, (2008) 1409.
[6] S. Fukuzumi, K. Ohkubo, Y. Morimoto, Phys. Chem. Chem. Phys. 14, (2012) 8472.
[7] M. Witwicki, M. Jerzykiewicz, A. R. Jaszewski, J. Jezierska, A. Ozarowski, J. Phys. Chem. A 113 (2009),
113, 14115.
[8] M. Witwicki, J. Jezierska, J. Phys. Chem. B 115 (2011), 3172.
[9] M. Witwicki, J. Jezierska, Theor. Chem. Acc. 132, (2013), 1383.
[10] M. Witwicki, M. Jerzykiewicz, A. Ozarowski, Chemosphere 119, (2015), 479.
[11] M. Jerzykiewicz, M. Witwicki, J. Jezierska, Chemosphere 138, (2015), 233.
28
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
FORMATION OF REACTIVE OXYGEN SPECIES ON THE AMORPHOUS
NONREDOX MATERIALS DURING REACTION WITH H2O2
K. Sobańska,1 P. Pietrzyk
1, Z. Sojka
1
1 Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow, Poland
H2O2 decomposition is commonly catalyzed by transition-metal oxides, but also less
conventional materials of non-redox nature, such as amorphous transition-metal oxides, exhibit
activity in generation of reactive oxygen species (ROS) from H2O2. The redox active materials
show typical Fenton-like reactivity, while for the non-redox oxides formation of ROS is not
trivial and involves interfacial electroprotic reactions [1]. In this contribution reactivity of
amorphous ZrO2 oxide toward formation of ROS during interaction with H2O2 in aqueous
solutions was investigated by means of EPR spectroscopy, and auxiliary spectroscopic
techniques (Raman and UV-Vis).
The presence of superoxo groups was confirmed by EPR spectroscopy. The EPR spectra
recorded after treatment with H2O2 solution at various pH values represent a signal
characteristic of surface-stabilized O2–
species. The symmetry and shape of the signal is
insensitive to pH, while its intensity changes strongly with acidity of the reaction medium. The
obtained spin-Hamiltonian parameters values (gxx = 2.0029, gyy = 2.0095, gzz = 2.0329) are
typical of superoxides. Temperature behavior of the observed signal (10 K – 77 K) and
additional HYSCORE measurements showed that O2–
species were stabilized via H-bonding
with surface hydroxyls, on the contrary to a reference material of amorphous Nb2O5, for which
the presence of hyperfine splitting due to 93
Nb (I = 9/2) nuclei indicated direct bonding with
the metal core [1].
Generation of OH radicals in the ZrO2/H2O2 system was confirmed by means of EPR using
DMPO spin trap and additionally with the characteristic reaction involving OPD substrate.
After admission of amorphous ZrO2 to H2O2 aqueous solution in the presence of OPD, a band
in the UV-Vis spectrum located at around 440 nm appeared, proving formation of OH
radicals.
The spectral intensities of detected types of ROS changed strongly with pH of the reaction
mixture. This observation indicated that the processes leading to ROS generation must have
involved a proton transfer step. The experimental relationship between the concentration of OH and O2
– radicals versus pH showed that both types of ROS were formed simultaneously
following the electroprotic mechanism (HO2– + H2O2 = O2
– +
OH + H2O). Thus, it was
shown that amorphous ZrO2 exhibited peroxidase-type reactivity, and consequently, the nature
of ROS could effectively be controlled by varying pH of the reaction medium.
Acknowledgement
This work was financially supported by National Science Center Poland based on the decision
no. DEC-2015/17/N/ST5/01956.
References [1] M. Ziółek, I. Sobczak, P. Decyk, K. Sobańska, P. Pietrzyk and Z. Sojka, Appl. Catal. B: Environmental, 164
(2015) 288.
29
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
RADIATION-INDUCED PARAMAGNETIC CENTERS IN SOME BORATE GLASSES
B. V. Padlyak1,2
1 Division of Spectroscopy of Functional Materials, Institute of Physics
, University of Zielona Góra,
4a Szafrana Str., 65-516 Zielona Góra, Poland 2 Sector of Spectroscopy, Vlokh Institute of Physical Optics, 23 Dragomanov Str., 79-005, Lviv, Ukraine
The undoped lithium tetraborate (Li2B4O7) and other borate single crystals are
characterized by very high radiation stability to influence of different kinds of ionizing
radiation. Only fast and thermal neutrons of high fluence (more than 1015
cm2
) leads to
generation of stable paramagnetic centers in the lattice of Li2B4O7 single crystals, which were
investigated in [1,2] by electron paramagnetic resonance (EPR) technique.
In this report the X-band ( 9.4 GHz) electron paramagnetic resonance (EPR) spectra of the
series borate glasses with LiB3O5, SrB4O7, CaB4O7, Li2B4O7, KLiB4O7, SrB6O10, and
LiCsB6O10 chemical compositions, irradiated by high dose of the - ray (107 Gy) and X - ray (1
2 · 104 R) at room temperature have been presented and analyzed. The nominally-pure borate
glasses of high chemical purity and optical quality were obtained from corresponding
polycrystalline compounds by standard glass synthesis using technological conditions
described in [3].
The analysis of EPR spectra of the - and X - irradiated borate glasses shows presence
radiation-induced paramagnetic centers stable at room temperature practically in all
investigated glasses. The most intense and well-resolved EPR spectra of the radiation-induced
centers have been observed in the Sr-contained borate glasses. Detailed analysis of the
observed EPR spectra shows that the registered spectra belong to radiation-induced
paramagnetic centers, which can be described in the framework of model of the O hole centers
in different sites of borate glass network. The 4-component EPR spectrum of the O centers are
related to the superhyperfine (SHF) structure, caused by interaction of the unpaired electron
spin with one nearest nucleus of the 11
B magnetic isotope (nuclear spin I = 3/2, natural
abundance – 80.1 %). In the irradiated borate glasses also were observed weak EPR signal with
7-component SHF structure that belong to the O centers, localized near one nucleus of the
10B
isotopes (nuclear spin I = 3, natural abundance – 19.9 %). Observed in the irradiated borate
glasses unstructured anisotropic EPR signal can be ascribed to the O hole centers, localized
near non-magnetic isotopes in the glass network. The EPR spectra of anisotropic O hole
centers without SHF structure were observed previously in the neutron-irradiated Li2B4O7
single crystals [1,2] as well as in the γ - and X - irradiated glasses of CaO-Ga2O3-GeO2 system
[4].
The features of EPR spectra, electronic and local structure and mechanisms of creation of the
radiation-induced centers in the borate glasses with different chemical composition are
discussed in comparison with available referenced data for EPR spectroscopy of the γ -, X -,
and neutron-irradiated borate crystals and glasses. Possible applications of the borate glasses
for radiation protected dosimetry as well as for different devices in space systems have been
considered.
References [1] Ya.V. Burak, B.V. Padlyak and V.M. Shevel, Nucl. Instr. Meth. Phys. Res. B 191 (2002) 633.
[2] Ya.V. Burak, B.V. Padlyak, V.M. Shevel, Radiat. Eff. Defects Solids 157 (2002) 1101.
[3] B.V. Padlyak, S.I. Mudry, Y.O. Kulyk, A. Drzewiecki, V.T. Adamiv, Y.V. Burak and I.M. Teslyuk, Mater.
Sci. Poland 30 (2012) 264.
[4] B.V. Padlyak, Radiat. Eff. Defects Solids 158 (2003) 411 .
30
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
FATTY ACIDS BINDING SITES AND CONFORMATIONAL CHANGES BY THE
BINDING OF THEM ON BOVINE SERUM ALBUMIN
A. Oleszko1, P. Mikoda
1, K. Gałecka
1, M. Komorowska
1
1 Wrocław University of Science and Technology
Department of Biomedical Engineering
Wybrzeże Wyspiańskiego 27
50-370 Wrocław, Poland
Human serum albumin (HSA) is a major protein component of blood plasma. It serves
as a transport protein for several endogenous compounds, such as unesterified fatty acids (FA)
and bilirubin, and is also capable of binding a broad spectrum of therapeutic agents. Drug
binding to HSA (human serum albumin) can result in a prolonged in vivo half-life. Thus, the
binding property of drugs to HSA is one of the most important factors determining their
pharmacokinetics [1]. Human serum albumin, as well as bovine serum albumin (BSA)
possesses multiple fatty acid binding sites of varying affinities, but the precise locations of
these sites have remained elusive. The determination of the crystal structure of human serum
albumin complexed with myristic acid (MYR) recently revealed the positions and architecture
of six binding sites on the protein [1,2].
Fig. 1. Ribbon model of HAS, fig 1a and HSA-MYR complex fig. 1b, derived from x-ray crystallography
(PDB entry 1E7G). HSA is composed of three homologous domains I–III, each of which is divided into two
subdomains, A and B. The six MYR molecules bonding into sites are shown on the fig 1b. The FA binding
sites are numbered from 1-6. Figures 1A and 1B clearly shows a conformational change of the protein due
to binding of the fatty acids.
In presented study, two high and low affinity FA binding sites on BAS (bovine serum albumin)
were discussed, based on the results of binding spin labeled FA (X-band EPR), and possible
conformational changes of BSA by ATR-FTIR methods.
References [1] S. Curry, P. Brick, N. P. Franks, Fatty Acid Binding to Human Serum Albumin: New Insights from
Crystallographic Studies, Biochim. Biophys. Acta 1441 (1999) 131-140
[2] S. Fujiwara and T. Amisaki, Identification of High Affinity Fatty Acid Binding Sites on Human Serum
Albumin by MM-PBSA Method, Biophysical Journal 94 (2008) 95–103 H. Author, M.E. Author and H.M.
Author, Journal Name Volume, (Year) page.
31
IV FORUM EMR-PL 27-29.VI. 2016
Invaited speaker
ESR INVESTIGATION OF FUNCTIONALIZED MAGNETITE NANOPARTICLES
R. Krzyminiewski1, B. Dobosz
1, J. Kurczewska
2, G. Schroeder
2
1 Medical Physics Division, Faculty of Physics, Adam Mickiewicz University, Poznań, Poland
2 Department of Supramolecular Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Poznań, Polska
Nanoparticles are considered as potential drug carriers in targeted therapies, e.g. anti-
cancer. Some of them can have a magnetic core e.g. magnetite or maghemite. Because of a
magnetic core, they may be controlled by appropriate magnetic fields. This would allow
directing functionalized nanoparticles to the affected area, e.g. a tumor and save the healthy
tissues. An excellent method for investigation the physical properties of functionalized
magnetite nanoparticles and their diffusion in the magnetic field is electron spin resonance
(ESR) [1-3].
In this study TEMPO-functionalized magnetite nanoparticles in water, chloroform and
toluen solutions with three different coatings: chitosan, silane or PEG, have been investigated.
In order to examine differences in the diffusion rates they were also added to human blood or
human serum. The ESR measurements were performed using X-band (9.4 GHz) Bruker
ESR/ENDOR EMX-10 spectrometer. The ESR spectra were recorded in the temperature range
of 115 K– 300 K in a magnetic field sweep width of 650 mT and 20 mT [1,3]. So called field
cooling method FC was also used for calculation magnetic properties of magnetic core and
dynamics of spin labels attached to the core. To investigate the diffusion rate the sample was
kept in the inhomogeneous magnetic field which source was a neodymium magnet. In this part
of experiment the sample was measured in 230 K. Ten positions of a sample in a resonator
were measured and then using a special own software the concentration of nanoparticles in
particular layers was determined giving the information about the previously diffusion [2].
For all ESR spectra typical spectroscopic parameters like g-factor value, peak-to-peak
line width (ΔHpp) and for TEMPO correlation time (τ) have been determined. On the basis of
these results for functionalized nanoparticles two types of information can been obtained: one
about the magnetite core and the second one about the dynamics of TEMPO [1]. The results of
nanoparticles diffusion in different solvents (water, human blood or human serum) were shown
that the rate of this process depends on the solvent and the time during which the sample is
kept in the inhomogeneous magnetic field [2]. The advanced CREM method of increasing
resolution of experimental spectra was used. Thanks to this analysis the narrow central line was
detected with isotropic g-value and amplitude increasing with increasing temperature. Probably
this line is connected to the amorphous surface of nanoparticle magnetic core [3].
References [1] B. Dobosz, R. Krzyminiewski, G. Schroeder and J. Kurczewska, Journal of Physics and Chemistry of Solids
75 (2014) 594–598.
[2] B. Dobosz, R. Krzyminiewski, G. Schroeder and J. Kurczewska, Current Applied Physics 16 (2016) 562–567.
[3] B. Dobosz, R.Krzyminiewski, M.Koralewski and M.Hałupka-Bryl, Journal of Magnetism and Magnetic
Materials 407 (2016) 114–121.
32
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
APPLICATION OF QUALITATIVE STANDARDS TO INTERPRETATION OF EPR
SPECTRA OF PLANT MATERIAL
M. Kurdziel1, M. Łabanowska
1, M.Filek
2
1Faculty of Chemistry, Jagiellonian University, Kraków, Poland
2The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków, Poland
EPR spectra of native plant material are often very complex and their interpretation is
sometimes uncertain. In order to improve the scientific reliability of attribution of signals to
defined species, the standard samples of particular compounds found in plant tissues have been
applied. As biological material grains of various cereals as well as their parts have been used.
The signals found in their spectra have been preliminary ascribed to transition metal ions, such
as Fe(III), Mn(II) in organic and inorganic surroundings. Moreover, several types of organic
radicals’ signals have also been detected. It has been assumed that they originated from carbon
centered radicals and radicals of phenoxyl type.
Mn(II) signal present in the spectra consisted of two lines with the g factor about 2.0. Well
resolved six lines of hyperfine structure with A 9.2 mT were overlapped on a broad signal.
The g value has suggested the oxide surroundings of Mn ions. Therefore, the samples of Mn(II)
ions in low and high concentration, dispersed in MgO matrix, have been chosen as standards.
The spectrum of a sample containing low Mn(II) concentration has shown characteristic hfs
typical for isolated Mn species. With the increasing amount of Mn(II) in the samples the signal
broadened and lost its hf structure, which was caused by increasing dipole – dipole
interactions.
Signals of Fe(III) with g in the range of 2.2 - 2.3 recorded at room temperature disappeared at
77 K, indicating that paramagnetic ions Fe(III) were antiferromagnetically coupled.
Simultaneously, the broad signal at g about 2.4 - 2.6 grew with lowering temperature. It has
been known, that in plant material iron species are accumulated in the inorganic “iron-core” of
ferritin as well as in the ferritin protein shell. Therefore, the sample of ferritin of biological
origin was registered as a standard. The parameters of standard spectrum and its temperature
characteristics were similar to those observed in grains spectra.
The structures of the spectra of some radical species recorded in grains suggested their origin
from carbon centered radicals. Such radicals can be formed in carbohydrate and protein
biomolecules, hence, the samples of saccharose, starch and albumine with radicals generated
by UV-irradiation and thermal treatment were used as standards. Character of their signals and
EPR parameters confirmed our supposition.
The origin of the second type of organic radicals was proved by comparing their signals with
those found in the spectra of samples of hydroquinone and tyrosine subjected to UV treatment.
33
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
ELECTRON DONOR-ACCEPTOR PROPERTIES OF MELANIN STUDIED BY EPR
AND REDOX POTENTIOMETRY
Z. Matuszak1
1Department of Medical Physics and Biophysics, Faculty of Physics and Applied Computer Science, Academy of
Mining and Metallurgy, AGH-UST, Cracow, Poland
Melanins are natural pigments of polymeric character, widespread in virtually all living
organisms, both in animal and plant kingdoms. In mammals these polymers are found
principally in the skin, hair, in the eye, the brain and in the inner ear. Melanin has many
functions: it can act as radicals scavenger, chelating agent, binds many organic compounds,
xenobiotics etc. The most known function of these pigments are their photoprotective
properties. Light absorption by the polymer is accompanied by redox reactions and electron
transfer processes within its granules. Protection against the oxidative and nitrosative stress by
melanin is also related to its redox activity. Melanin itself is paramagnetic. The intensity of
EPR signal of melanin is often used as measure of its redox activity. Despite many studies of
the redox interactions of melanins with various oxidizing and reducing agents, only few
investigations were focused on the fundamental redox properties of these polymers, e.g. the
redox potential E0 of melanin remains unknown.
In this communication a series of redox titration of DOPA-melanin (DM) in acidic
solution with various strong oxidants such as KMnO4, CeSO4, K2Cr2O7 etc. is reported. Changes
in redox potential values of DM/oxidant solution during titration were monitored using
platinized platinum electrode. EPR spectroscopy was used for additional control of progress of
reaction (detection of paramagnetic products of redox reaction).
A direct electron transfer (ET) between DM redox active groups (quinones) and oxidant
was confirmed in separated SE-EPR (Simultaneous Electrochemical EPR) experiment, in
which reaction between KMnO4 and DM was conducted on electrochemical way i.e. with
spatially separated reagents. Reduction of Mn(VII) to Mn(II) on helical platinum electrode
placed in EPR cavity was observed.
The redox titration curves of melanin are strongly asymmetric and the measured redox
potential remains practically constant during titration. These facts indicate that ET reactions of
melanin have a cooperative character, and that melanin itself demonstrates a huge redox
capacity. An apparent redox potential E0 for DM was estimated, E0≈700 mV (vrs. NHE).
In order to explain the cooperative character of ET processes in melanins (linear
dependence of melanin E0 on oxidation degree), a simple theory of ET equilibria based on
theory of lattice gases (Ising model) in mean-filed approximation was formulated and tested.
34
IV FORUM EMR-PL 27-29.VI. 2016
Invaited speaker
GRAPHENE OXIDE – EPR AND IMPEDANCE NEW INTERPRETATION
S. Łoś1, W. Kempiński
1, T. Bandosz
2, M. Kempiński
3
1Institute of Molecular Physics Polish Academy of Sciences, ul. M. Smoluchowskiego 17,
60-179 Poznań, Poland 2Department of Chemistry, The City College of New York, 160 Convent Ave,
New York, 10031, USA 3Faculty of Physics and NanoBioMedical Centre, Adam Mickiewicz University,
Umultowska 85, 61-614 Poznań.
The granular carbon materials became important as they can be used in devices for
energy storage and conversion [1-3]. Discovering the graphene results in increase of the
interest in carbon physical and chemical properties. It is supposed that a surface
functionalization allow to achieve materials for water dissociation reaction [4, 5]. We repot an
EPR and an impedance characterization of modified carbon materials. The EPR method is
excellent for testing the electronic states localized on the surface. The spectrum of common
granular active carbons consists of one slightly asymmetric line [6]. Its deconvolution reveal
three different electron states. However, EPR of graphene oxides of similar granular
distribution is characterized by the dysonian line-shape. It reveals a much higher density of
electrons delocalized within conducting band. The impedance spectroscopy is a
complementary method, which allow to investigate conductive properties of the sample. The
EPR double integral follow to temperature increase of the impedance. Such relation reveal that
localized state observed in EPR signal can be originated from electronic states located on the
interface between carbon grains and adsorbed molecules.
Acknowledgment
This work has been partially supported by grants: DEC-2013/09/B/ST4/03711 and DEC-
2013/11/B/ST3/041900.
References [1]. E. Frackowiak, F. Béguin “Carbon materials for the electrochemical storage of energy in
Capacitors” Carbon 39 (2001) 937–950
[2]. J. R. Miller and P. Simon “Electrochemical capacitors for energy management”. Science Magazine. 321
(2008) 651-652
[3]. D. Wang, F. Li, M. Liu, G. Q. Lu, and H. Cheng “3D Aperiodic Hierarchical Porous Graphitic Carbon
Material for High-Rate Electrochemical Capacitive Energy Storage” Angew. Chem. Int. Ed. 47 (2008) 373 –376
[4]. Y. A. Shaban, S.U.M. Khan “Visible light active carbon modified n-TiO2 for efficient hydrogen production by
photoelectrochemical splitting of water” Int. J. Hydrogen Energ. 33 (2008) 1118 – 1126
[5]. J. H. Park, S. Kim, and A. J. Bard “Novel Carbon-Doped TiO2 Nanotube Arrays with High Aspect Ratios for
Efficient Solar Water Splitting” Nano Letters 6 (2006) 24-28
[6]. Sz. Łoś, M. Letellier, Ph. Azaïs, L. Duclaux “Li doped carbon (activated microporous carbons and
graphite):characterization by resonance spectroscopies (ESR and 7Li NMR) and their potentiality for hydrogen
adsorption” J. Phys. Chem. Solid. 67 (2006) 1181-1185
35
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
DIELECTRIC AND EPR STUDIES ON FULLERENES: C60 AND C70
Z. Trybuła1, S. Łoś
1,W. Kempiński
1, M. Trybuła
1
1 Institute of Molecular Physics, Polish Academy of Sciences,
Smoluchowskiego 17, 60-179 Poznań, Poland
The influence of absorbed oxygen from the air on the physical properties of fullerenes:
C60 and C70 will be presented. We will report dielectric and EPR studies of the C60
monocrystalline sample and C60 and C70 thin films [1-7]. The monocrystal of the virgin,
oxygen free C60 exhibits typical first order structural phase transition behavior: There is a
discontinuous change in real part of electric permittivity at the phase transition temperature
[1, 7]. The symmetry is lowered from fcc to sc phase and the lattice parameter changs
by0.005nm [8]. Such alternations implies changes in polarizability of the C60 lattice. However,
the absorbed oxygen affects the mechanism of the structural phase transition at Tc=260K in the
monocrystal of C60. This is the reason of the experimental evidence for the drastic change in
the temperature dependence of the real part of electric permittivity. During the cooling run in
the vicinity of phase transition, the real part of electric permittivity jumps down for oxygen free
C60 monocrystal [1, 3, 7]. For crystal exposure to oxygen [1, 9-11] there is observed an
opposite effect.
The fullerene materials (C60 or C70) with no oxygen contact is EPR silent.
Measurements revealed that light – air exposure causes an increase of the number of C60+ and
C70+ [2, 6] paramagnetic defects. This effect was related to oxygen diffusion into pristine
fullerene samples. If the oxygen is removed by sample vacuum pumping, the amplitude of the
EPR signal decreases. Once again exposure of these materials to the air results in signal
restoring in a very short time. Repeating this procedure in inert atmosphere e.g. with nitrogen
N2 gives no EPR effect.
References [1] Z. Trybuła, Sz. Łoś, W. Kempiński, M. Trybuła and L. Piekara-Sady, J. Phys.: Condens. Matter 21, (2009)
435402.
[2] W. Kempiński, Sz. Łoś, Z. Trybuła, L. Piekara-Sady, A. I. Shames, S. Shutina and E. A. Katz, Karbo 4-5,
(2000) 141.
[3] Z. Trybuła, Sz. Łoś, W. Kempiński, M. Trybuła, S. Shutina, A. I. Shames and E. A. Katz, Karbo 4-5, (2000)
139.
[4] Z. Trybuła and M. Krupski, Acta Phys. Pol. A 98, (2000) 389.
[5] Z. Trybuła, W. Kempiński, Sz. Łoś, I. Shames, S. Shutina and E. A. Katz, Molecular Physics Reports 34/2,
(2001) 154.
[6] W. Kempiński, L. Piekara-Sady, E. A. Katz, A. I. Shames and S. Shutina, Solid State Commun. 114, (2000)
173.
[7] J. Stankowski, W. Kempiński, Z. Trybuła, P. Byszewski and W. Krätschmer, Ferroelectrics 155, (1994) 109.
[8] W. I. F. David, R. M. Ibberson, T. J. S. Dennis, J. P. Hare, K. Prassides, Europhys. Lett. 18, (1992) 219.
[9] B. Pevzner, A. F. Hebard, M. S. Dresselhaus, Phys. Rev. B 55, 1(1997) 6 439.
[10] A. Fartash, Phys. Rev. B 54, (1996) 17215.
[11] T. B. Tang and M. Gu, Fiz. Tverdogo Tela 44, (2002) 607.
36
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
STRUCTURAL AND MAGNETIC ORDER AND DISORDER IN METAMAGNETIC
SHAPE MEMORY ALLOYS Ni2Mn1+xIn1-x
M. Kuźma1
1 Biophysics Chair, Rzeszow University , 35 959 Rzeszow , Rejtana 16a , Poland
Shape memory effect (SME) in ferromagnetic shape memory alloys (SMA) based on
Heusler alloys of X-Y-Z type (X = Ni; Y = Mn, Co, Fe; Z = Ga, Sb, Sn, In) is attributed to the
structural transition from high-temperature austenitic phase to low-temperature martensitic
phase and to the combination of ferromagnetic properties of the martensite and thermoplastic
properties of the martensite transformation. There are two groups of the classical SMA :
Ni2MnGa-type and Ni2MnZ-type (Z = Ge, Sn In). The first family shows the SME strongly
enhanced by off-stoichiometric composition of the material, whereas the second family shows
martensitic transition, and therefore the SME, only at off-stoichiometric conditions. It was
observed experimentally that a giant SME was detected when magnetic phase transition at
Curie temperature TC occurs simultaneously with structural austenite-martensite transition at
temperature TM [1]. Merging of these temperatures can be achieved by changing the
stoichiometry. Therefore, the off-stoichiometry is the principal reason of structural disorder
which drives magnetic properties of the SMA. The typical tendency in off-stoichiometric Ni2-
Mn-Ga systems is that martensitic transformation temperature is increased, while Curie
temperature is decreased by deviation from stoichiometry. The increase of Tm is explained by
increase of electron concentration e/a in the system . The lowering of the Curie temperature
arises from decrease of the exchange interaction between Mn atoms.
Fig. 1. An EPR signal of Ni2Mn1+x In1-x (x =0.41) measured at T = 300K (a ) and temperature dependence of
the integral intensity (b).
Magnetic properties of the Ni2Mn1+x In1-x differs from that for Ni-Mn-Ga Heusler alloys, while
magnetization in the austenitic phase (cubic L21) increases with Mn content increasing [2]. It
means that the excess of Mn on In sublattice should be ferromagnetically coupled instead of
antiferromagnetically. Our electron paramagnetic resonance measurements (Fig.1) confirm the
paramagnetic-antiferromagnetic transition in the Ni50Mn35.5In14.5 (x = 0.41) alloy at room
temperature.
References [1] V.V. Khovailo, T. Takagi, A.N. Vasilev, H. Miki, M. Matsumoto, R. Kainuma, Phys. Rev. B 72, 224408
(2005).
[2] C.-M. Li, H.-B. Luo, Q.-M. Hu, R. Yang, B. Johansson, L/ Vitos, Phys. Rev. B 86, 214205 (2012).
37
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
ELECTRON PARAMAGNETIC RESONANCE AND OPTICAL STUDY OF
Ca4GdO(BO3)3 SINGLE CRYSTALS AFTER IRRADIATION BY BISMUTH IONS
I. Stefaniuk1, P. Potera
1 A. Badyła
1
1 Faculty of Mathematics and Natural Sciences,
University of Rzeszow1 Pigonia Str., 35-959 Rzeszow Poland
Gadolinium calcium oxoborate Ca4GdO(BO3)3 (GdCOB) crystals are of great interest
due to their excellent nonlinear optical properties [1]. GdCOB has the monoclinic noncentro-
symmetric structure with two molecules per unit cell and space group symmetry Cm [2]. The
EPR measurements were performed at room temperature and in the temperature range from 95
K up to 300 K . The selected EPR spectra are presented in Figs 1 The aim of this paper is to
determine the nature of centers produced in the GdCOB crystal after irradiation by bismuth
ions. Quantitative analysis of EPR spectra has been carried out using the program EMR_NMR
assuming spin Hamiltonian for triclinic site symmetry. The fundamental absorption edge of the
GdCOB crystal is above 47000 cm-1
, in the region below the crystal is transparent. After
irradiation by bismuth ions with energy 11.4 MeV/u (MeV per nucleon) and a fluence 51011
cm-1
at room temperature the growth of absorption of the crystal was observed. We note, that
unstructured absorption growth was early observed in lithium niobate crystal for irradiation by
high energy gadolinium ions with similarity fluency [3]
Fig. 1. Angular dependence of the EPR spectra of GdCOB crystal after irradiation by bismuth ions
References [1] A.Brenier, A.Majchrowski, E.Michalski, T.Łukasiewicz, Opt. Commun., 217, (2003) 395.
[2] F. Mougel, A. Kahn-Harari, G. Aka, D. Pelenc, J. Mater. Chem. 8 (1998) 1619.
[3] B. Canut, R. Brenier, A. Meftah, P. Moretti, S. Ould, S.M.M. Ramos, P. Thevenard, M. Toulemonde, Nucl.
Instr. Meth. B 91, (1994) 312-316.
0 1000 2000 3000 4000 5000 6000 7000
Inte
nsi
ty [
arb
. u.]
Magnetic field [Gs]
Angle [ ] 0 510 1520 2530 3540 4550 5560 6570 7580 8590 95100 105110 115120 125130 135140 145150 155160 165170 175180 185190 195200 205210 215220 225230 235240 245250 255260 265270 275280 285290 295300 305310 315320 325330 335340 345350 355
38
IV FORUM EMR-PL 27-29.VI. 2016
Plenary speaker
MAGNETIC TRANSITION-METAL AND RARE-EARTH ADATOMS ON SURFACES
– EMR PERSPECTIVE
C. Rudowicz1,2
, K. Tadyszak3, M. Karbowiak
4
1 Visiting Professor: Faculty of Chemistry, A. Mickiewicz University, Poznań, Poland
2 On leave of absence from: Institute of Physics, West Pomeranian University of Technology Szczecin, Poland
3 NanoBioMedical Centre, Adam Mickiewicz University, Poznań, Poland
4 Faculty of Chemistry, University of Wrocław, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland
The atomic scale and low-dimensional magnets based on transition-metal (TM) and
rare-earth (RE) adatoms on surfaces [1,2] have attracted huge interest in view of potential
applications for high-bit density of data storage [3-5]. Due to recent advances in
nanotechnology it is now possible to build magnetic lattices using vertical atom manipulation
and to probe them locally. This gave tremendous boost to scanning tunneling microscopy
(STM) and inelastic tunneling spectroscopy (ITS) studies and opened avenue for realizing
quantum systems and study transitions to classical limit. Extracting experimental quantities
from density functional theory (DFT) and/or ab-initio calculations for adatoms on surfaces
presents significant difficulties. This is partially due to the gap between the DFT/ab-initio
techniques and the semi-empirical ones employed in optical spectroscopy, electron magnetic
resonance (EMR/EPR) spectroscopy, and magnetism. The concepts underlying these areas
form nowadays an intricate web of interrelated notions at the interface between the physical
Hamiltonians and the effective (spin) Hamiltonians [6,7], which are often confused [6-8].
Description of adatoms properties crucially depends on proper interpretation of experimental
STM/ITS data and their meaningful comparison with DFT/ab-initio results [9,10].
In this presentation the following topics will be covered. (1) Introduction to physics behind
adatoms studies, with focus on relationships between the classical magnetic anisotropy energy
(MAE), single-ion anisotropy (SIA), zero-field splitting (ZFS), and spin-flip energy of
tunneling electrons. (2) Links between adatoms studies and EMR techniques based on ZFS
Hamiltonians. (3) Clarifications concerning the MA=ZFS and MA=CF confusion, i.e. labelling
the true ZFS quantities and the true CF (crystal or ligand field) quantities as purportedly the
MA (SIA) quantities [6,10], prevalent in TM and RE adatoms studies, respectively. (4)
Implications of the incorrect relations between MAE (SIA) and ZFS quantities identified in
adatoms literature. (5) Standardization of non-standard ZFSP sets used in adatoms studies.
Finally, we mention the 'ZFS terms' recently introduced for spin S=1/2 'contrary to common
belief' [11,12] and adopted for Cu2+
systems [13].
References [1] H. Brune, P. Gambardella, Surface Science 603, 1812 (2009).
[2] J.-P. Gauyacq, N. Lorente, F. D. Novaes, Progress in Surface Science 87, 63 (2012).
[3] A. Spinelli, M. P. Rebergen, A. F. Otte, J. Physics: Condensed Matter 27, 243203 (2015).
[4] J. Dreiser, J. Physics: Cond. Matter 27, 183203 (2015).
[5] A. Caneschi, D. Gatteschi, F. Totti, Coordination Chemistry Reviews 289–290, 357 (2015).
[6] C. Rudowicz, M. Karbowiak, Coordination Chemistry Reviews 287, 28 (2015).
[7] C. Rudowicz, S. K. Misra, Applied Spectroscopy Reviews 36, 11 (2001).
[8] C. Rudowicz, M. Karbowiak, Physica B: 451, 134 (2014); ibidem 456, 330 (2015).
[9] C. Rudowicz, M. Karbowiak, Phys. Rev. B 93, 184415 (2016).
[10] C. Rudowicz, K. Tadyszak, submitted April (2016).
[11] J. Liu, et al., J. Chem. Phys. 141, 124113 (2014).
[12] H. J. Xiang, et al., Phys. Rev. B 83, 174402 (2011).
[13] A. T. Apostolov, et al., Modern Physics Letters B 29, 1550086 (2015).
39
IV FORUM EMR-PL 27-29.VI. 2016
Invaited speaker
THE EPR SPECTRA OF BULK ANTHRACITE UNDER STRONG COUPLING OF A
SPIN ENSEMBLE TO RESONATOR
R. Fedaruk1, K. Tadyszak
2,3, R. Strzelczyk
3, M.A. Augustyniak-Jabłokow
3
1 Institute of Physics, University of Szczecin, Szczecin, Poland
2 NanoBioMedical Centre, Adam Mickiewicz University, Poznań, Poland
3 Institute of Molecular Physics PAS, Poznań, Poland
The strong photon-matter coupling, including coupling between a microwave resonator
and an ensemble of electron spins, has attracted increasing attention in quantum information
processing [1,2]. A quantum effect called vacuum Rabi splitting is the signature of this
coupling. Its solid-state analog can be realized in EPR studies of materials with high spin
density and a narrow EPR line. Recently this effect was shown for large samples of anthracite
[3]. But the size- and temperature- dependent anomaly of the EPR signals of anthracite can be
due to the skin effect [4].
In this report we present the temperature dependences of the EPR signal of bulk anthracite. At
low temperatures the strong spin-resonator coupling is revealed by bistability and hysteresis of
EPR signals (Fig. 1 a and b). The weaker coupling results in the super-Lorentzian EPR
lineshape (Fig. 1c). Changes of microwave frequency during EPR signal recording were used
to estimate the spin-resonator coupling strength.
Our results allow discrimination of the strong spin-resonator coupling from other reasons of the
EPR line distortion and correct interpretation of the EPR signals of materials with high spin
density, especially at low temperatures.
Fig. 1. EPR spectra and the microwave oscillator frequency recorded for the large (25 mg) and small (1.4
mg) samples. The microwave power was 0.5 mW. Black and grey lines in (a) and (b) show spectra recorded
with increasing and decreasing magnetic field, respectively. Grey lines in the bottom part of (c) depict two
branches of the microwave frequency due to the Rabi splitting.
References [1] E. Abe, H. Wu, A. Ardavan and J.J.L. Morton, Appl. Phys. Lett. 98, (2011) 251108.
[2] I. Chiorescu, N. Groll, S. Bertaina, T. Mori and S. Miyashita, Phys. Rev. B 82, (2010) 024413.
[3] R. Fedaruk, S.V. Adashkevich, J. Appl. Spectroscopy 81, (2014) 355.
[4] K. Tadyszak, R. Strzelczyk, E. Coy, M. Maćkowiak, M.A. Augustyniak-Jabłokow, Magnetic Resonance in Chemistry 54, (2016) 239.
320,2 320,4 320,6
8,9772
8,9776
8,9780
Mic
row
ave
fre
qu
en
cy,
GH
z
B, mT
(a) T = 4.2 K
EP
R s
ign
al
320,6 320,8 321,0
8,9878
8,9879
8,9880
8,9881
B, mT
(b) T = 25 K
320,6 320,8 321,0
8,9928
8,9930
8,9932
B, mT
(c)
Lorentz line
T = 4.2 K
40
IV FORUM EMR-PL 27-29.VI. 2016
Oral presentation
INTERPRETATION OF “ANOMALOUS” TEMPERATURE DEPENDENCIES OF
EPR SIGNAL INTENSITY IN VARIOUS SYSTEMS
M.A. Augustyniak-Jabłokow1
1 Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland
EPR signal intensity is proportional to paramagnetic susceptibility. Therefore, the
signal intensity is expected to be either reversibly proportional to temperature (I~1/T) or, in a
case of conduction electrons, independent of temperature. In practice, one meets a number of
anomalous I(T) dependencies resulting from various factors, such as gradual localization of
conduction electrons [1], thermal exciting to the paramagnetic state [2, 3], changes of the
magnetic order [4] or complicated and conformation dependent structure of energetic levels in
the systems with total spin S>1/2 [5, 6]. There are cases, when similar I(T) dependencies are
due to very different reasons. Analysis of such dependences requires special attention and deep
knowledge about properties of the studied material, but can yield significant information
concerning properties of the studied material
In the present report various approaches to several “anomalous” I(T) dependencies are shown
and discussed.
Fig. 1. Examples of the “anomalous” I(T) dependencies due to: transition to antiferromagnetic state in
graphene – 1; temperature induced changes of conformation of structural fragments in the amorphous
carbon – 2; structural phase transition, which influences order of the energetic levels in the mixed valence
cluster of [V4IV
V2VO7(OCH3)12] crystal – 3 down (temperature) and 3 up. For comparison the Curie–type
dependence is shown – 4.
References [1] K. Tadyszak, M.A. Augustyniak-Jabłokow, A.B. Więckowski, L. Najder-Kozdrowska, R. Strzelczyk, B.
Andrzejewski, Carbon, 94, (2015) 53.
[2] G. Wagoner, Physical Review 118 (1960), 647.
[3] K.Lewandowska, W. Bednarski, G. Milczarek, S. Waplak, A. Graja, A., E.Y. Park, T.D. Kim,K.S. Lee,
Synthetic Metals 161 (2011). 1640.
[4] M.A. Augustyniak-Jabłokow, K. Tadyszak, M. Maćkowiak, Y.V. Yablokov, physica status solidi (RRL), 5(8),
(2011) 271-273.
[5] M.A. Augustyniak-Jabłokow, S.A. Borshch, C. Daniel, H. Hartl, Y.V. Yablokov, New Journal of Chemistry
29, (2005) 1064.
[6] Khavryuchenko, M.A. Augustyniak, Submitted to Inorganic Chemistry (2016).
41
Poster contributions
42
IV FORUM EMR-PL 27-29.VI. 2016
Poster I
EUPHORBIA TURKESTANICA TANNINS – ANTIRADICAL ACTIVITY,
INTERACTION WITH ALPHA-HEMOLYSIN AND ERYTHROCYTES LIPIDS
M. Bitiucki1, S. Sękowski
1, E. Olchowik-Grabarek
1, N. Abdullajanova
2, M. Zamaraeva
1
1 Institute of Biology, University of Bialystok, Bialystok, Poland
2 Institute of Bioorganic Chemistry, Academy of Science of Uzbekistan, Tashkent, Uzbekistan
Oxidative damage of erythrocytes cause eryptosis and cells elimination from blood
result in anemia. It was found that polyphenols like flavonoids can reduce the oxidative stress
level and protect erythrocytes from damage [1]. Tannins as a group of polyphenolic
compounds [2] may exhibit similar activity. In this study tannins isolated from an Asian plant
Euphorbia Turkestanica (1,2-di-O-galloyl-4,6-valoneoyl-β-D-glucose; 2-O-galloyl-4,6-
valoneoyl-β-D-glucose and 3-O-galloyl-4,6-valoneoyl-β-D-glucose) have been investigated
using EPR spectroscopy to analyze the scavenging activity against stable free radicals DPPH
(2,2-diphenyl-1-picrylhydrazyl). We have found that studied tannins possess the antiradical
activity against DPPH in the range 0.5-20 µM. By using fluorescence spectroscopy we have
measured fluorescence quenching of alpha-toxin’s tryptophans, caused by 3-O-galloyl-4,6-
valoneoyl-β-D-glucose, which previously showed antihemolytic activity against the bacteria
Staphylococcus aureus. It has been shown that tannins, depending on the concentration,
significantly reduces the fluorescence signal which indicates its strong binding to alpha-
hemolysin.
Using the same method and Laurdan (fluorescent label), we investigated the influence of
tannins on the liposomes fluidity prepared from human erythrocytes lipids, as a model of cell
membranes. Results of membrane fluidity investigation show that all three tannins cause the
decrease of membrane stiffness.
References [1] F. An, S. Wang, D. Yuan, Y. Gong, S. Wang, Attenuation of Oxidative Stress of Erythrocytes by Plant-
Derived Flavonoids, Orientin and Luteolin, Evid Based Complement Alternat Med., 2016, 2016:3401269
[2] K.T. Chung, T.Y. Wong, C.I. Wei, Y.W. Huang, Y. Lin, Tannins and human health: a review, Critical
Reviews in Food Science and Nutrition, Volume 38, Issue 6 (1998)
43
IV FORUM EMR-PL 27-29.VI. 2016
Poster II
MAGNETIC INVESTIGATIONS OF Nb6Sb3VO25
J. Typek1, G. Zolnierkiewicz
1, M. Bobrowska
1, E. Filipek
2, M. Piz
2
1Institute of Physics, West Pomeranian University of Technology, Szczecin, Poland
2Department of Inorganic and Analytical Chemistry, West Pomeranian University of Technology, Szczecin,
Poland
The compound of the formula Nb6VSb3O25 in the Nb-V-Sb-O system was obtained by
solid state reaction method [1]. EPR and dc magnetisation techniques were used to characterise
magnetically this phase (Fig. 1). Although the nominal valence of the constituting ions
indicated on a non-magnetic substance, Nb6VSb3O25 displayed rich and interesting magnetic
behavior due to numerous defects. The number of magnetic defects was calculated to be
equivalent to roughly of a quarter of vanadium ions in non-nominal +4 oxidation state (3d1,
S=1/2). Dc isothermal magnetisation study indicated that part of other ions may be also in non-
nominal states forming pairs and clusters of magnetic ions.
2.5 3.0 3.5 4.0 4.5
-8
-6
-4
-2
0
2
4
6
8
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0 5 10 15 20 25 30 35 40 450
20
40
60
80
100
120
140
160
180
Magnetic field [T]
EP
R a
mplit
ud
e [a
rb.u
nits]
Magnetic field [kOe]
4 K
290 K
(A)
0 1 2 3 4 5 6 7
0.00
0.05
0.10
0.15
0.20
0.25
290 K
60 K
10 K
Ma
gn
etiza
tio
n [B
/f.u
.]
2 K
(C)
0 50 100 150 200 250 3000.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
EP
R in
teg
rate
d in
ten
sity [a
rb.u
nits]
Temperature [K]
(B)
0 50 100 150 200 250 300
0
10
20
30
40
50
60
70
80
Temperature [K]
Temperature [K]
[1
0-3
em
u/m
olO
e]
FC10 Oe
(D)
Re
cip
rocal E
PR
inte
gra
ted
in
ten
sity [a
rb.u
nits]
[m
olO
e/e
mu
]
Fig. 1. (A) EPR spectra of Nb6Sb3VO25 recorded at 4 and 290 K; (B) Temperature dependence of EPR
integrated intensity (left axis) and reciprocal EPR integrated intensity (right axis); (C) Isothermal
magnetisation registered at four different temperatures; (D) Temperature dependence of magnetic dc
susceptibility, insert shows low-temperature part of the inverse magnetic dc susceptibility.
References
1. E. Filipek, M. Piz, J. Alloy. Compd. 661 (2016) 141.
44
IV FORUM EMR-PL 27-29.VI. 2016
Poster III
SPATIAL- AND SPECTRAL-SPATIAL IMAGING - AN APPLICATION TO EPRI
OXIMETRY
A. Boś-Liedke 1,3
, K. Tadyszak 3, T. Czechowski
3,4, M. Walawender
1,2, Z. Kabacińska
1, S.
Jurga 2,3
1 Department of Medical Physics, Faculty of Physics, Adam Mickiewicz University,
ul. Umultowska 85, PL 61614 Poznan, Poland 2 Department of Macromolecular Physics, Faculty of Physics, Adam Mickiewicz University,
ul. Umultowska 85, PL 61614 Poznan, Poland 3 NanoBioMedical Centre, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland
4 noviLET ul. Piotrowo 3, 61-138 Poznań
The history of Electron Paramagnetic Resonance Imaging (EPRI) started in 1979 when
this phenomenon was published by Hoch and Day [1]. At that time it was demonstrated that it
is possible to reveal the spatial distribution of paramagnetic centers in diamond. This fact
became a starting point in development of methodology and new equipment for EPR imaging.
There are three widely used techniques in EPRI: Continuous Wave (CW), Pulse, and Rapid
Scan Technique, where CW is the most widely used. There are two ways to perform an
imaging experiment – by the spatial imaging and by the spectral-spatial imaging (SSI). The
first one gives an information about the position of unpaired spins, whereas the second one
about the line width of each point of the image [2]. Moreover the SSI approach determines the
interactions of spin probes with paramagnetic molecules that is used e.g. in imaging of tissue
oxygenation. Therefore, the result of SSI in the case of O2 molecules is an oxygenation map of
the selected tissues.
In the standard SSI, each projection is recorded multiple times with different gradient
amplitudes. Unfortunately, such a procedure cause the 3D and 4D SSI measurements too long
for animal applications.
The following study shows the results of spatial and spectral-spatial image reconstruction
technique (2D, 3D, 2D SSI, 3D SSI), with some signal to noise ratio improvements, allowing
for the shortening of the measurement time.
Acknowledgements
Financial support from the National Science Centre (UMO-2014/15/B/ST4/04946), is
gratefully acknowledged.
References [1] M.J.R. Hoch, A. R. Day, Solid State Communications, 1979, 30, 211 – 213.
[2] T. Czechowski et al. Journal of Magnetic Resonance 248 (2014) 126–130
45
IV FORUM EMR-PL 27-29.VI. 2016
Poster IV
EMR SPECTRA OF ZNO THIN FILMS DOPED WITH HIGH CONCENTRACTION
OF CO AND CR ON QUARTZ AND SAPPHIRE SUBSTRATES
B. Cieniek1, I. Stefaniuk
1, I.Virt
1,2
1Faculty of Mathematics and Natural Sciences, University of Rzeszow, Pigonia 1, 35-959 Rzeszow, Poland
2Ivan Franko Drohobych State Pedagogical University, 24, I. Franko Str., 82100 Drohobych, Ukraine
Diluted Magnetic Semiconductors (DMS) and their properties have potential
applications in the spin-dependent semiconductor electronics [1] due to the spin-spin exchange
interaction between the localized magnetic moments and the band electrons [2]. We have
studied magnetic properties of zinc-oxide composite doped with high concentrations (20%) of
Co and Cr ions. The pulsed laser deposition (PLD) method were used to obtain samples on two
different substrates, quartz glass and sapphire. Samples were annealed in 100 – 250 C for ZnO
with quartz substrate, and 300 - 700 C with sapphire substrate. Electron paramagnetic
resonance (EPR) measurements were carried out and temperature dependence of the EPR
spectra was obtained. The angular dependence in two samples orientation were also obtained.
Analysis of the temperature dependences of the integral intensity of EPR spectra was carried
out using the Curie-Weiss law.
Fig. 1. ZnO:Cr annealed, with Curie temperature equal to 166,6 °C
Fig. 2. ZnO:Cr not annealed, angular dependence with horizontal orientation
References [1] D.D. Awshalom, D. Loss and N. Samarth (Eds.), Semiconductors Spintronics and Quantum Computation,
Springer, Berlin, (2002).
[2] W. Dobrowolski, J. Kossut, Handbook of Magnetic Materials, 15, (Ed. K.H.J. Bushow), Elsevier, (2003).
46
IV FORUM EMR-PL 27-29.VI. 2016
Poster V
EPR STUDY OF Cu-Mn-Zn SPINELS SUPPORTED ON DEALUMINATED HY(–Al)
ZEOLITE
P. Decyk1, A. B. Więckowski
2,3, L. Najder-Kozdrowska
3, M. Ziółek
1, I. Bilkova
1
1 Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland
2 Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland
3 Institute of Physics, Faculty of Physics and Astronomy, University of Zielona Góra, Zielona Góra, Poland
[email protected], [email protected]
Dealuminated HY(–Al) zeolite has been modified by supporting of Cu-Mn-Zn spinels
according to the procedure given by Fei et al. [1]. The loading of spinels in the HY(–Al)
zeolite was in the range of 0.5-25 wt%. The EPR spectra of samples with 10 wt% loading were
recorded at temperatures from 77 K to 403 K, whereas the spectra of materials with loading of
0.5 to 25 wt% were taken of at 77 K and 293 K. For all samples, independent of loading, three
types of lines were observed in the EPR spectra. The first line is a broad one, which originated
from the spinels on the surface of the zeolite. The second one is an anisotropic line that can be
attributed to four-component hyperfine structure (hfs) from isolated Cu2+
cations (S = 1/2, 63
Cu, 65
Cu, I = 3/2 both). The third signal, an isotropic line comes from six-component hfs of
isolated Mn2+
cations (S = 1/2, 55
Mn, I = 5/2). With the increase in the concentration of spinels
phase individual hfs lines from Cu2+
and Mn2+
undergo broadening due to spin-spin
interactions what causes the reducing of the resolution of spectra measured at 293 K. For all
samples regardless of spinels loading, the spectra recorded at 77 K have shown only a single
nearly symmetric EPR line. The linewidth of these lines growths with increasing the
concentration of the spinels in HY(–Al) zeolite. The analysis of
250 300 350 400
a
b
Inte
nsit
y [
a.u
.]
Magnetic field [mT]
the main values of g and A tensors show that Cu2+
complexes posses the form of elongated octahedra
[2]. The linewidth of individual hfs lines of Mn2+
complexes is strongly dependent on the
temperature, what is illustrated in Fig. 1. This
indicates the role of dynamic processes (e.g.
random tumbling) occurring in the Mn2+
complexes.
Fig. 1. EPR spectra of dealuminated HY(–Al) zeolite doped
with Cu-Mn-Zn spinels (10 wt%) recorded at 273 K (a)
and 373 K (b).
Additionally dealuminated HY(–Al) zeolite doped with Cu-Mn-Zn spinels was also evacuated
at different temperatures. It is worth noting that EPR spectra recorded at 77 K for evacuated
catalyst to 573 K do not show significant changes of the lineshape and the line intensity. Only
evacuation at 673 K caused a dramatic reduction of the signal intensity. This may indicate on
the transformations that took place in the spinels deposited on HY(–Al) zeolite.
References [1] J. Fei, Z. Hou, B. Zhu, H. Lou, X. Zheng, Appl. Catal. A-Gen., 304, (2006) 49.
[2] P. Decyk, A.B. Więckowski, L. Najder-Kozdrowska, I. Bilkova, Nukleonika 60, (2015) 423.
47
IV FORUM EMR-PL 27-29.VI. 2016
Poster VI
FERROMAGNETIC RESONANCE IN NiCoMnIn LAYERS OBTAINED BY PULSED
LASER DEPOSITION
Ł. Dubiel1, M. Kuźma
1, W. Maziarz
2, I. Stefaniuk
3, P. Sagan
1, G. Wisz
4, A. Wal
1
1Faculty of Mathematics and Natural Sciences, Department of Biophysics, University of Rzeszow, Pigonia 1, 35-
959 Rzeszow, Poland 2Institute of Metallurgy and Materials Science of the Polish Academy of Science, 25 Reymonta Str., 30-059
Krakow, Poland 3Faculty of Mathematics and Natural Sciences, Center for Microelectronics and Nanotechnology, University of
Rzeszow, Pigonia 1, 35-959 Rzeszow, Poland 4Faculty of Mathematics and Natural Sciences, Department of Experimental Physics, University of Rzeszow,
Pigonia 1, 35-959 Rzeszow, Poland
The alloys of the type Ni-Mn-Z (Z = Ga, Sb, Sn, In) are potential candidates as
materials for spintronics technology. Depending on composition and temperature these alloys
exhibit ferromagnetic semimetal properties. In the case of the Ni50-xCox Mn50-yIny the Curie
temperature is above room temperature, therefore these alloys may have practical interest. The
layers of Ni50-xCox Mn50-yIny have been grown by means of pulsed laser deposition (PLD) on
(100) Si substrate. The target was bulk Ni50-xCox Mn50-yIny (x=5,y = 14.5) alloy prepared by
induction melting of pure elements under argon atmosphere [1]. The morphology of the layers
and composition were studied by electron microscopy TESCAN Vega3 equipped with EDS
spectrometer Bruker (10 mm2, 133 eV). The layers were grown in PREVAC PLD system using
YAG Nd3+
LITRON laser operating at second harmonic. In Fig.1a. the typical morphology of
the layers is presented .
Fig.1. SEM image of a layer deposited on (100) Si substrate (a), angular dependence of a resonance field (b).
Magnetic properties were investigated on Bruker X band EPR spectrometer (9.36GHz) at room
temperature. The magnetic resonance spectrum consists of one non-symmetric line with
resonance field within wide field range (250-500 mT). The resonance field depends strongly on
a position of the layer in respect to magnetic field (in plane, out of plane). The angular
dependence is addressed according to ferromagnetic resonance.
References
[1] W. Maziarz , Solid State Phenomena 186, (2012) 251
48
IV FORUM EMR-PL 27-29.VI. 2016
Poster VII
WIDE TEMPERATURE RANGE SYSTEM FOR EPR MEASUREMENTS
UP TO 1300 K
Z. J. Frączek1, M. Wencka
1, S. Turczyński
2
1Institute of Molecular Physics Polish Academy of Sciences, Poznań, Poland
2Institute of Electronic Materials Technology, Warszawa, Poland
Heating system for spectroscopic measurements in temperature range from 5 K up to
1300 K is presented. Hardware together with software possibilities contain: X-band
RADIOPAN SE/X 2547 Spectrometer, resonator, quartz cryostat, temperature controller,
temperature sensor, nitrogen dewar, flow meter, nitrogen heating subsystem and control PC
computer. For tests of high temperature EPR measurements we performed experiments of
Y4Al2O7 (YAM) doped by europium that is a new laser, scintillating and sensing material. At
heating run we detected Eu2+
(S=7/2) that exhibit broad EPR spectrum. EPR signal intensities
show two maxima at 425 K and 700 K that are related with oxidation/reduction processes
between Eu2+
and Eu3+
.
Fig. 1. To avoid over heating consecutive measure points are reached in small steps.
49
IV FORUM EMR-PL 27-29.VI. 2016
Poster VIII
MAGNETIC PROPERTIES OF STEEL BALLS INVESTIGATED BEFORE AND
AFTER NITRIDING PROCESS
H. Fuks1, S.M. Kaczmarek
1, G. Leniec
1, J. Michalski
2,3, B. Kucharska
4, P. Wach
2
1 Zachodniopomorski Uniwersytet Technologiczny w Szczecinie
2 Instytut Mechaniki Precyzyjnej
3 Szkoła Główna Gospodarstwa Wiejskiego w Warszawie
4 Politechnika Częstochowska
Nitriding is a thermo-chemical treatment of the steel improves its wear resistance,
corrosion resistance and hardness. Nitrided layer affects the magnetic and electric properties of
the steel. The article presents the results of magnetic and electric studies of nitrided steel balls.
Samples, as well as before and after thermal treatment, were investigated with using EPR and
SQUID techniques. The aim of presented work was to find general connections between
different chemical composition of steel, different procedure of thermal treatment and magnetic
properties concluded from EPR and SQUID investigation.
EPR spectra revealed wide and intense signals visible at whole accessible temperature range.
Position of each signal, far from geff≈ 2 expected for Fe magnetic ions, indicates on complex
nature of responsible magnetic centers. Another feature confirming existence of complex
magnetic sites arises from unusual increasing of the intensity of EPR signal as a function of
temperature.
From the point of view of EPR experiment, magnetic centers are better distinguished for higher
carbon containing materials, whereas low carbonated samples usually gives EPR signal
strongly disturbed and far from expected Lorentzian shape.
Similar situation is observed if one compares the resonance signal before and after thermal
treatment. When nitrogen inclusions appear on the steel surface, the EPR signal becomes more
symmetric and close to standard Lorentzian line.
Well defined thermal processes, described as Nx1021 and Nx1025 also gives significantly
different EPR resonance signal, which indicates that, as well as temperature and time of staying
in nitrogen atmosphere have influence on magnetic properties of presented steel materials.
Results obtained from SQUID experiment confirmed unusual behavior of magnetic
susceptibility as a function of temperature and generally are consistent with EPR results.
In presented work we find out and describe connections between some mechanical, electric and
magnetic properties of investigated steel materials. According to presented results, such
properties could be controlled with using of very sensitive techniques as EPR and SQUID
methods.
50
IV FORUM EMR-PL 27-29.VI. 2016
Poster IX
MONITORING OF PLATELET MEMBRANE FLUIDITY DURING DIALYSIS OF
SHEEP
K. Gałecka1, T. Walski
1, J. Bujok
2, K. Grzeszczuk-Kuć
1, J. Detyna
3, M. Komorowska
1
1 Department of Biomedical Engineering, Wrocław University of Science and Technology, Poland
2 Department of Animal Physiology and Biostructure, Wrocław University of Environmental and Life Sciences,
Poland 3 Department of Mechanics, Materials Science and Engineering, Wrocław University of Science and Technology,
Poland
Platelet plasma membrane is thought to participate in mediating signal transduction
processes. The changes of platelet membrane fluidity is one of the signs of the activation
process or pathological states [1-8]. Among the methods to monitor molecular membrane
organization is the spin probe method where paramagnetic molecules diffusing into a
membrane and reflecting its rigidity states are used. Here we demonstrated a simple way which
provides information on alterations in the membrane fluidity of blood platelets. In this method
platelets in platelet-rich plasma (PRP) samples were studied to avoid washing procedures that
activate cells. The glass surface was employed as an activator by placing the PRP samples in
glass capillaries. Surface-induced platelet activation and accompanied membrane changes were
analyzed by electron paramagnetic resonance (EPR) measurements. The EPR spectra of the 16-
doxylstearic acid labeled platelets were recorded as a function of time and a parameter of the
membrane fluidity were calculated. Activation of platelets was associated with an increase of
fluidity of the membrane to the equilibrium state which was reached after 10 min. contact with
a glass surface that correspond to taking the fully spread form by platelets.
The method was tested on sheep platelets upon haemodialysis (HD) procedures which is
known to promote haemostasis disorders, activate immune cells or impair blood elements [9-
10]. For each animal procedures were repeated ten times as short daily HD sessions. During
each procedure blood was drawn prior to, after ca. 15 minutes and at the end of HD from the
arterial and venous lines and were used as research material. In addition, blood of half sheep
(five) flowing via dialyzer were exposed to near infrared (NIR) radiation. It has been
demonstrated that NIR light can produce a beneficial effects on cells, therefore were applied to
study its protective action during HD.
EPR spectra indicated the reduction of the membrane fluidity of platelets from blood exposed
to NIR radiation. The results of experiments corresponded with better aggregability of
irradiated platelets investigated by impedance aggregometer.
References [1] M. Steiner and E.F. Lüscher, Biochemistry, 23(2), (1984) 247–252
[2] A. Kantar et al., Mediators Inflamm., 1(2), (1992) 127–131
[3] I. Nathan et al., J. Biol. Chem., 254, (1979) 9822–9828
[4] S. Kitagawa, T. Shinohara and F. Kametani, J. Membr. Biol., 79(1), (1984) 97–102
[5] R.D. Sauerheber et al., J. Membr. Biol., 52(3), (1980) 201–219
[6] S.J. Shatti, D.B. Cines and A.D Schreiber., J. Clin. Invest., 61(3), (1978) 582–589
[7] G.S. Zubenko et al., Psychopharmacology (Berl), 145(2), (1999) 175–180
[8] C. Watala et al., Eur. J. Haematol., 61(5), (1998) 319–326
[9] M. Olszewska, Ann. Acad. Med. Stetin, 50, (2004) 41-52
[10] V. Sirolli et al., Int. J. Artif. Organs, 25, (2002) 529-537
51
IV FORUM EMR-PL 27-29.VI. 2016
Poster X
SPIN LABELING STUDIES OF ERYTHROCYTES PROPERTIES IN VARICOSE
VEINS PATIENTS
L. Gwoździński1,2
, A. Pieniążek3, J. Bernasińska
4, M. Grabowski
1, E. Kowalczyk
4, K.
Gwoździński4
1General Surgery Ward, K. Jonscher Municipal Medical Center, Lodz, Poland.
2Department of Pharmacology and Toxicology, Medical University of Lodz, Lodz, Poland.
3Department of Medical Biophysics, Faculty of Biology and Evironmental Protection, University of Lodz, Lodz,
Poland. 4Department of Molecular Biophysics, Faculty of Biology and Evironmental Protection, University of Lodz, Lodz,
Poland.
Introduction: Varicose veins are enlarged veins of the subcutaneous tissue occurring
most commonly on the superficial veins of the lower limb. They are usually caused by faulty
or damaged venous valves leading to impaired blood flow. Blood stasis, excessive clotting
disorder and alterations in the vein walls are symptoms of Virchow’s triad which may affect
the morphotic elements of blood, such as erythrocytes.
Purpose: The aim of this study was to investigate alterations in erythrocytes properties
in varicose veins in comparison to the antecubital vein of patients with chronic venous disease.
The investigation was conducted in whole erythrocytes using spin labeling method in EPR
spectroscopy.
The plasma membrane fluidity was measured using two spin labeled fatty acids (5-DS and and
16-DS). The internal viscosity of cells was determined by Tempamine. The conformation state
of internal proteins, mainly hemoglobin was determined by maleimide spin labels.
Methods: Venous blood samples in EDTA from eight patients with chronic venous disease
(age: 45-55 years) were taken from the antecubital vein and varicose veins. Blood was
centrifuged and erythrocytes were washed thrice with cold PBS solution. The hematocrite was
50%. Erythrocytes were labelled with 5- and 16-doxylstearic acids. The internal viscosity
of cells was determined with Tempamine using Morse method [1]. The state of internal
proteins, mainly hemoglobin, was estimated by maleimide spin label-MSL [2].
Results: A significant increase in lipid membrane fluidity indicated by 5-DS and 12-DS was
observed in varicose vein erythrocytes in comparison to the erythrocytes from the antecubital
vein. The internal viscosity of varicose vein erythrocytes was significantly lower than in the
erythrocytes taken from antecubital vein. However, we did not find changes in the state of
internal proteins in the erythrocytes from varicose and antecubital vein measured using a
maleimide spin label.
Conclusion: The erythrocytes from varicose veins show lower lipid membrane fluidity and
lower internal viscosity than the erythrocytes obtained from antecubital non-varicose veins.
These alterations can result in an increased risk of varicose veins erythrocytes structure
deformations as compared to the erythrocytes from antecubital veins.
References [1] P.D. Morse, Methods in Enzymology, 127, 1986, 239–249.
[2] K. Gwozdzinski, Toxicology, 65, 1991, 315-323.
52
IV FORUM EMR-PL 27-29.VI. 2016
Poster XI
RADIATION DEFECTS IN CALCITE AND THEIR INFLUENCE
ON MECHANICAL PROPERTIES
Z. Kabacińska1*, L. E. Coy
2, R. Krzyminiewski
1, M. Wencka
3
1 Medical Physics Division, Faculty of Physics, Adam Mickiewicz University,
Umultowska 85, 61-614 Poznań, Poland
2 NanoBioMedical Centre, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan, Poland
3 Department of Solid State Radiospectroscopy, Institute of Molecular Physics, Polish Academy of Sciences,
Smoluchowskiego 17, 60-179 Poznań, Poland
Generation and recombination of defects generated by γ, X- and UV radiation in calcite
(CaCO3) and their influence on mechanical properties were investigated [1]. Calcium carbonate
is one of the most abundant minerals in the nature, and it has wide applications in many
branches of industry e.g. as a filler in plastics, rubber and paper [2]. Its property to accumulate
some structural defects, often referred to as the time effects, that appear under the effect of
natural radiation has been used in EPR dating of e.g. cultural objects or constructions [3]. EPR
studies were performed on the X-band (9.7 GHz) Bruker EPR spectrometer (EMX-10 type).
Measurements of mechanical properties were conducted by means of the nanoindentation
technique. Additionally, X-ray diffraction and Scanning Electron Microscopy were used for
sample characterisation. We examined natural and synthetic calcite, subjected to UV irradiation
from a low pressure Hg lamp and to γ irradiation from a Co60 source. Analysis of EPR
measurements has shown that UV light generates similar defects in calcite as γ radiation.
Moreover, our observations confirm a strong correlation between the morphology and size of
crystals and the presence of particular types of defects with characteristic geometries generated
by a particular radiation. Namely, the isotropic symmetry of CO2- defect (g-factor 2.0007) is
favoured in the samples with a less regular morphology of spherical and ‘cigar-like’ aggregates
of smaller crystals, while the orthorhombic CO2- defects (gx = 2.0030, gy = 2.0017, gz =
1.9973) are more abundant in the samples of well-defined rhombohedral crystals. In the less
regular synthetic calcite the UV-induced defects occur in a relatively small concentration.
Measurements of mechanical properties of the natural calcite single crystal revealed a decrease
in hardness and Young modulus after γ, X-ray and UV irradiation. A correlation between these
changes and the type and number of radiation defects was established on the basis of EPR
measurements of a powdered single crystal.
Acknowledgements This work was supported by the Operational Program ’Human Capital’ - PO KL 4.1.1,
’Proinnowacyjne kształcenie, kompetentna kadra, absolwenci przyszłości’.
References [1] Z. Kabacińska, R. Krzyminiewski andB. Dobosz, Rad. Prot. Dos., 159, (2014) 1-6.
[2] H.S. Katz, and J.V. Milewski, Handbook of fillers for plastics, Van Nostrand Reinhold, New York, (1987).
[3] M. Ikeya, New applications of electron spin resonance: dating, dosimetry and microscopy, World Scientifc,
Singapore, (1993).
53
IV FORUM EMR-PL 27-29.VI. 2016
Poster XII
EPR INVESTIGATIONS INTO FORMATION OF NITROSYL COMPLEXES
OF PALLADIUM CATIONS IN ZEOLITES Y AND ZSM-5
A. Krasowska1, K. Podolska-Serafin
1, P. Pietrzyk
1
1 Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow, Poland
Nitrogen oxides (NOx) are among the most harmful air polluting compounds. Their
removal requires a catalyst which incorporates selected transition metal ions. One of them is
palladium, which plays an important role in catalytic reduction of NOx. In this context metallo-
zeolites are extensively studied as model systems exhibiting required catalytic activity. The use
of zeolite as a support allows for the generation of isolated cationic centers whose valence
state, being a key factor for interaction with NO, can be controlled to a certain degree.
Owing to its electronic properties, NO molecule (*1) can be studied by means of electron
paramagnetic resonance (EPR) spectroscopy. In fact, EPR is sensitive both to the gas-phase
reactant as well as to the palladium active sites (Pd3+
, 4d7 and Pd
+, 4d
9), whose valence state is
decisive for the EPR parameters or lack of EPR signal (4d8 electron configuration, Pd
2+).
Chemical nature of the active sites depend on the thermal treatment of the samples. When
activated in dioxygen (Fig. 1a), isotropic EPR signal shows formation of Pd(III) cations (giso =
2.23) [1], while reduction in H2 (Fig. 1b) leads to a more complicated, multicomponent signal
(g|| ≈ 2.90 – 2.74 and g ≈ 2.13 – 2.11), characteristic of Pd(I) [1].
Both in the case of oxidized and reduced zeolite, reaction with NO results in an EPR signal
with a characteristic hyperfine structure. It comes from the coupling with the magnetic moment
of nucleus 105
Pd (22.3%, I = 5/2). In addition, in the case of interaction with Pd(I), the
superhyperfine structure can be observed, which was assigned to two nuclei of nitrogen (14
N, I
= 1) coming from dinitrosyl species Pd+(NO)2. While in the case of Pd(I) they are formed by
simple addition reaction 2Pd + 2
2NO =
2{Pd
+(NO)2}, for the oxidized centers reactive
adsorption is observed which leads first to a reduction of Pd3+
to Pd2+
and Pd+, and subsequent
formation of the paramagnetic mono- Pd2+
NO and dinitrosyls Pd+(NO)2.
Fig. 1. EPR spectra (X band, T = 77 K) recorded before and after adsorption of NO on Pd-Y sample after a)
activation in dioxygen and b) reduction in hydrogen.
Acknowledgement
This work was financed by National Science Center Poland based on the decision no. DEC-
2013/11/D/ST4/02838
References [1] L.S. Stokes, D.M. Murphy, R.D, Farley, C.C. Rowlands, S. Bailey, Phys. Chem. Chem. Phys., 1 (1999) 621.
54
IV FORUM EMR-PL 27-29.VI. 2016
Poster XIII
EPR STUDY OF PARAMAGNETIC CENTERS ON A SURFACE OF MODIFIED
NANODIAMONDS
A. Krupska1, R. Strzelczyk
1, M.A. Augustyniak-Jabłokow
1
1 Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland
EPR studies of nanodiamonds [1-2] showed that the observed EPR spectrum is
dependent on the method of production and processing. Nanodiamonds can be obtained by
various method, both static and dynamic ones such as chemical vapor deposition (CVD),
technique of high temperature and pressure (HPHT), detonation of materials containing carbon
and others. In this report we describe results obtained for the detonation nanodiamonds,
separated into individual crystallites and ultrasonically dispersed, to form a stable suspension
in water [3]. The concentration of paramagnetic centers reaches 4x1020 spin/g. Obtained results
indicate presence of both, localized and delocalized centers. We discuss the origin of the signal
and its stability. The possible sources of the EPR signal of nanodiamonds are: dangling bonds
due to broken on a surface sp3 bonds, conduction electron, defects of the bulk and surface
structure of nanodiamonds, paramagnetic impurities eg. NV-, Fe
3+, forbidden transition S=2)
for triplet states. Annealing of nanodiamonds at 500 oC in air removes the graphitized surface
layer and the EPR signal disappears. Annealing thus prepared nanodiamonds in vacuum at a
temperature of ~200 C removes the functional groups and exposes the dangling bonds. EPR
spectrum of such sample is composed of two broad, signals of high intensity, which quickly
disappear with time leaving a weak, broad signal.
Fig.1 EPR spectrum of nanodiamonds; 1 – with graphitized surface; 2 – annealed at 500°C and cleaned in
vacuum at ~200 °C; 3 – the same sample as 2, but after 24 hours; 4 – signal of resonator
References [1] A.I. Shames, A.M. Panich, W. Kempiński et al., Journal of Physics and Chemistry of Solids 63, (2002) 1993-
2001.
[2] A.I. Shames, V.Yu. Osipov, H.J. von Bardeleben and A.Ya. Vul, J. Phys.: Condens. Matter 24, (2012) 225302-
225400.
[3] E.D. Eidelman, V.I. Siklitsky, L.V. Sharonova et al., Diamond & Related Materials 14, (2005) 1765 – 1769.
55
IV FORUM EMR-PL 27-29.VI. 2016
Poster XIV
EPR STUDY OF THE MAGNETIC PROPERTIES OF IRON OXIDE
NANOPARTICLES IN HUMAN BLOOD AND SERUM
T. Kubiak1, R. Krzyminiewski
1, B. Dobosz
1, J. Kurczewska
2, G. Schroeder
2
1 Medical Physics Division, Faculty of Physics, Adam Mickiewicz University in Poznań
2 Department of Supramolecular Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Poznań
Fe3O4 nanoparticles are perfect candidates for drug carriers due to a number of
favorable properties such as biodegradability, chemical stability, low toxicity and
superparamagnetic behavior. However, the research on the properties of functionalized
magnetite nanoparticles and their interaction with human serum and whole blood is crucial
prior to the introduction of nanoparticles into clinical practice.
Functionalized magnetite nanoparticles with a core diameter of 5 nm were investigated in
aqueous solution, human serum and whole human blood by means of X-band (9,4 GHz)
Bruker EPR/ENDOR EMX-10 spectrometer. The measurements were carried at room
temperature and in the temperature range 125-265K. Paramagnetic centers naturally occurring
in the blood (Fe3+
ions in transferrin and methemoglobin; Cu2+
ions in ceruloplasmin) were
identified prior to the addition of nanoparticles. The EPR spectrum of magnetite nanoparticles
has a form of a broad line. The values of EPR line parameters were different for nanoparticles
in water, serum and blood, which indicated the influence of the environment on the properties
and interactions of nanoparticles. Field cooling (FC) experiment showed that the value of g
factor for the orientation 0o is greater than for 90
o, so the external resonance field is higher for
the angle of 90o. The use of computer resolution enhancement method (CREM) allowed to
separate an additional narrow spectral component (g = 1.99) from the EPR spectra of magnetite
nanoparticles. The presence of this line might be related to the phenomena occurring on the
surface of the nanoparticle core.
Fig. 1. The CREM analysis (Lorentz, core width 20 pt.) of EPR signal of magnetite nanoparticles in whole
human blood at temp 230K.
References [1] T. Kubiak, R. Krzyminiewski, B. Dobosz, G. Schroeder, J. Kurczewska, M. Hałupka-Bryl, Acta Bio-Optica et
Informatica Medica Biomedical Engineering 21, (2015), 9-15.
[2] T. Kubiak, R. Krzyminiewski, B. Dobosz, Current Topics in Biophysics 36 (2013), 7-13.
[3] R Krzyminiewski, T Kubiak, B Dobosz, G Schroeder, J Kurczewska, Current Applied Physics 14 (2014), 798-
804.
[4] B. Dobosz, R. Krzyminiewski, M. Koralewski, M. Hałupka-Bryl, Journal of Magnetism and Magnetic
Materials, 40 (2016), 114-121.
56
IV FORUM EMR-PL 27-29.VI. 2016
Poster XV
OPTIMIZATION OF ANTIOXIDANT PROPERTIES OF WATER-IN-OIL AND OIL-
IN-WATER CREAMS WITH BILBERRY, CHOKEBERRY AND ELDERBERRY
EXTRACTS BY ARTIFICIAL NEURAL NETWORKS
K. Makarova1, K. Zawada
1, D. Wagner
1, J. Skowyra
1, M. Trębińska
1, I. Wawer
1
1 Department of Physical Chemistry, Faculty of Pharmacy, The Medical University of Warsaw, Banacha 1, 02-
097 Warsaw, Poland
Oxidative stress and the excess of free radicals accelerate the aging process of human
skin. The application of skin cream with antioxidant compounds could reduce the damage
caused by free radicals. In this work we studied two types of skin creams with extracts from
chokeberry (Aronia melanocarpa), elderberry (Sambucus nigra) and bilberry (Vaccinium
myrtillus) due to their high content of anthocyanins, which are strong natural antioxidants. The
DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging ability of the skin creams with berry
extracts was studied with Electron Spin Resonance (ESR) spectroscopy. The Artificial Neural
Networks (ANN) were applied to optimize the berry extract concentration and storage time for
oil-in-water and water-in-oil creams [1]. Based on experimental results, chokeberry and
elderberry extracts in oil-in-water cream base revealed higher DPPH radical scavenging ability
than corresponding water-in-oil samples. ANN predicted maximum of DPPH radical
scavenging of oil-in-water creams for elderberry (2.23 mg DPPH/ml) cream stored for 1 week
and freshly prepared chokeberry (5.37 mg DPPH/ml) and bilberry (5.26 mg DPPH/ml) creams
with the 0.76% concentration of extract. The maximum of DPPH radical scavenging for water-
in-oil creams was predicted for the 0.8% Aronia extract cream stored for 6 weeks, the freshly
prepared cream with 0.76% bilberry extract and the cream with 0.56% elderberry extract stored
for 1 week. The ANN predicted values are in good agreement with experimental values. Thus,
DPPH-EPR could be combined with ANN in order to optimize the extract concentration, type
of cream base and to predict the effect of storage based on limited number of experiments and
samples.
References [1] S. Haykin, Neural Networks: A Comprehensive Foundation (2nd Edition), Prentice Hall PTR, Upper Saddle
River, NJ, USA, (1998).
57
IV FORUM EMR-PL 27-29.VI. 2016
Poster XVI
HYPERFINE STRUCTURE OF VANADIUM IONS IN LIQUIDS AND SOLIDS
I. Mrówka1, B. Pytel
1, D. Man
1
1 Institute of Physics, University of Opole, Opole, Poland
Vanadium is a silver-gray, ductile metal with high hardness and high melting point. For
an element with an atomic number 23 there is known 26 isotopes with mass numbers of 40 to
63. Only one stable isotope is the one with mass number 51. Chemically not very active at
room temperature, vanadium at high temperature react with oxygen, hydrogen, nitrogen
dioxide and water vapor . The presence of vanadium in nature is quite common and widely
used in industry. His most important minerals are: patronit VS4 and vanadinite Pb5[Cl(VO4)]3,
in terms of prevalence in the earth's crust occupies 23th place. The atmosphere appears
primarily as a component of continental dust, sea spray and volcanic emissions. The main
source of vanadium in surface waters are waste. It is used mainly for the production of non-
ferrous alloys, highly resistant carbon steel, as well as in the chemical, glass, ceramics, paint
and photo industries.
Vanadium is a component of living organisms, important for their proper functioning. In higher
concentrations reveals the toxic properties leading to poisoning and damaging biological
structures. There exists also reports of potential anticancer activity. Because vanadium has a
paramagnetic properties may be examined by electron paramagnetic resonance. In the course
of the research to date, the following substances were used: vanadium (III) chloride VCl3,
vanadium III acetylacetonate C15H21O6V and vanadyl (IV) acetylacetonate VO (C5H7O2)2, also
were used sodium benzoate and water and methanol as solvents. Presented here vanadium
compounds are powders - spectra of pure powders have a total domination of the fine structure
of the hyperfine structure, thus demonstrating a much greater intensity of interaction between
the spins of electrons than the interaction of spins of electrons with spins of nuclei. Completely
different situation, we have in the solutions. The weakening of intermolecular interactions in
liquids influences the narrowing of the energy levels and the disclosure in the spectra hyperfine
structure. In the case of powders produced based on sodium benzoate, in which the vanadium
ions are an admixture we have dealing with the indirect situation. In these substances revealed
hyperfine structure, however, the ratio of intensities of individual lines is greatly disturbed and
suffer the same lines move on the axis of the magnetic induction - which leads to a narrowing
of the whole spectrum.Within the theoretical analysis of results attempted to use for this
purpose the package Mathematica. So far, interesting results were obtained with the measuring
liquid samples, further work in this area are carried on.
Conclusion - commonly found in nature vanadium on the one hand there is an essential
element for the functioning of living organisms (it may even have therapeutic properties),
on the other hand, there are risks associated with dissemination of its manufacturing. The fact
that the element exhibits paramagnetic properties allows to apply the method of electron
paramagnetic resonance to study its compounds. The authors of this work are interested in the
influence of the vanadium on the biological structures, with respect to this there exists plans to
undertake in the near future studies on the effects of vanadium on the durability of membranes
model.
58
IV FORUM EMR-PL 27-29.VI. 2016
Poster XVII
SPECIFICITY OF FREE RADICAL-SCAVENGING PROPERTIES OF SUMAC
TANNINS IN PROTECTION OF ERYTHROCYTES AGAINST OXIDATIVE STRESS
E. Olchowik-Grabarek1, S. Mavlyanov
2, N. Abdullajanova
2,
R. Gieniusz3, M. Zamaraeva
1
1Department of Biophysics, University of Bialystok, K. Ciolkowskiego 1J, 15-245 Bialystok, Poland
2Institute of Bioorganic Chemistry, Academy of Science of Uzbekistan, Abdullaev 83,
100125 Tashkent, Uzbekistan 3Laboratory of Magnetism, University of Bialystok, K. Ciolkowskiego 1L., 15-245 Bialystok, Poland
Tannins, polyphenoles with the molecular mass ranging between 500 and 3000 Da, are
characterized by high chemical activity and a variety of biological effects, such as antitumor,
antimutagen, antimicrobial, and anti-inflammatory [1,2].
In this study, we show using EPR method that extract and 3,6 bis-O-di-O-galloyl-1,2,4-
tri-O-galloyl-β- D-glucose (C55H40O34) displayed a strong antiradical activity against the
synthetic DPPH radical in homogenous (solution) and hetereogeneous systems (suspension
of DPPH containing liposomes).
We also examined the antioxidant activity of extract from sumac leaves containing
tannins (98%) and flavonoids (2%) and also its main component - 3,6 bis-O-di-O-galloyl-1,2,4-
tri-O-galloyl-β- D-glucose (C55H40O34) against reactive oxygen and nitrogen species (RONS),
such as hydroxyl radical (.OH), superoxide radical (O
.-2), singlet oxygen (
1O2) and nitric oxide
(NO.) in the model system and RONS generated by tert-butyl hydroperoxide (tBuOOH),
peroxynitrate (ONOO-) and hypochlorous acid (HClO) in erythrocytes.
We found that the effectiveness of scavenging of RONS in relative to oxidants can be
represented by following order: tBuOOH > ONOO- > HClO. It is closely associated with
a specificity of neutralization of various RONS in model systems (O.-
2 ≥ NO > .OH>
1O2 ).
The extract from sumac was significantly more effective in comparison with 3,6 bis-O-
di-O-galloyl-1,2,4-tri-O-galloyl-β- D-glucose against RONS in all models.
References [1]. S. Rayne and G. Mazza, Biological activities of extracts from sumac (Rhus spp.): a review. Plant Foods for
Human Nutrition, 62 (2007) 165-175.
[2]. V. Koleckar, K. Kubikova, Z. Rehakova, K. Kuca, D. Jun, L. Jahodar and L. Opletal, Condensed and
hydrolysable tannins as antioxidants influencing the health. Mini Reviews in Medicinal Chemistry, 8 (2008) 436–
447.
59
IV FORUM EMR-PL 27-29.VI. 2016
Poster XVIII
MICROWAVE X-BAND RESONANCES IN DOPED Cd2Nb2O7 MONOCRYSTALS
S. Waplak1, A. Ostrowski
1, M. Wencka
1, W. Bednarski
1
1 Institute of Molecular Physics, Smoluchowskiego 17, PL-60179 Poznan, Poland
Cadmium pyroniobiate Cd2Nb2O7 (CNO) is a ferroic material with unusual diffuse
phase transition (PT) despite the absence of compositional fluctuations, unlike the conventional
relaxors PbMg1/3Nb2/3O3 (PMN), where a frequency-dependent broad dielectric peak is brought
about by nanoscopic polar clusters, but macroscopic ferroelectric ordering does not appear [1,
2]. We will present data strongly suggesting that both the ferroelectric/ferroelastic and local
order do coexist in Cd2Nb2O7 compounds and the interplay between them leads to a rich phase
diagram and relaxation [3-5].
Recently, attention has been paid to the possibility of electronic ferroelectricity based
on charge-ordering phenomena in complex oxides like perovskite structure manganites [6, 7].
An intriguing behavior of dielectric permittivity versus external electric field [8] stimulated us
to look closely on this problem by means of EPR spectra of doped Cd2Nb2O7.
Some EPR papers with the aim to study the molecular mechanism of the phase
transitions in Cd2Nb2O7 crystals have been published [9, 10]. Our papers [11,12] concerned
especially EPR of Cr3+
and Gd3+
ion dopants under the influence of temperature and/or external
electric field. The dielectric behaviour of cadmium pyroniobiate Cd2Nb2O7 shows “unusual
properties” around PT and strongly suggests the presence of polar clusters carrying additional
polarization. However, no molecular origin of such a behavior has been yet elucidated [8, 13].
The most striking effects observed in current study represent anomalies in the
microwave resonator quality parameter Q versus temperature in zero external magnetic field.
In Cd2Nb2O7, this effect appears only in the X-band ( 9.5 GHz) and is absent from the S-band
( 3.5 GHz). The details of the dependence Q = Q(T) rely on the type and concentration of the
doping (paramagnetic) ions Mn
2+, Cr
3+, Fe
3+ introduced. Currently, mainly electric (Q) data,
complemented with the EPR ones in case of necessity, will be discussed.
References [1] L. E. Cross, Ferroelectrics 76, (1987) 241.
[2] R. Blinc, Advanced Ferroelectricity, Oxford University Press Inc., New York, (2011).
[3] V. A. Isupov, Phys. Solid State 47, (2005) 2119.
[4] M.Tachibana, H. Kawaji, and T. Atake, Phys. Rev. B 70, (2004) 064103.
[5] N. N. Kolpakova, I. L. Shulpina, M. P. Shcheglov, S. Waplak, W. Bednarski, W. Nawrocik, and M. Wisner,
Ferroelectrics 240, (2005) 265.
[6] M. Falicov, and J. C. Kimball, Phys. Rev. Lett. 22, (1969) 997.
[7] N. Ikeda, H. Ohsumi, K. Ohwada, K. Ishii, T. Inami, K. Kakurai ,Y. Murakami, K. Yoshii, S. Mori, Y. Horibe,
and H. Kito, Nature 436, (2005) 1136.
[8] Chen Ang, L. E. Cross, Ruyan Guo, and A. Bhalla, Appl. Phys. Lett. 77, (2000) 732.
[9] I. N. Geifman, G. W. Sirotkin, and E. S. Sher, Fiz. Tverd. Tela 25, (1983) 3606.
[10] I. N. Geifman, Solid State Physics 21, (1979) 2251.
[11] N. N. Kolpakova, S. Waplak, and W. Bednarski, J. Phys. Cond. Matter 10, (1998) 9309.
[12] S. Waplak, and N. N. Kolpakova, phys. stat. sol.(a) 117, (1990) 461.
[13] R. Pirc, R. Blinc, and Z. Kutniak, Ferroelectrics 267, (2002) 139.
60
IV FORUM EMR-PL 27-29.VI. 2016
Poster XIX
POTENTIAL ROLE OF SUPEROXIDE ANION IN HOMOCYSTEINE-INDUCED
FLUIDIZATION OF PLATELET MEMBRANES – EVIDENCE FROM
PRELIMINARY EPR MEASUREMENTS
K. Karolczak1, P. Danielska
1, A. Pieniążek
2
1Department of Haemostatic Disorders, Faculty of Health Sciences, Medical University of Lodz, Lodz, Poland.
2Department of Medical Biophysics, Faculty of Biology and Evironmental Protection, University of Lodz, Lodz,
Poland.
Introduction: Homocysteine (Hcy) is a sulphur, non-protein amino acid, considered as
an important factor contributing to enhanced atherogenesis. The exact mechanism of Hcy-
dependent atherogenesis remained poorly understood, however, increased activation of blood
platelets by Hcy is thought to be a key factor in Hcy-driven atherosclerosis. Since Hcy is known
as potent oxidant we presumed that superoxide anion generated by Hcy during thiols oxidation
may act as mediator of Hcy-dependent changes in membranę fluidity.
Methods: The platelets were isolated from blood obtained from a forearm vein from healthy,
non-smoking donors, not taking any drugs or diet supplements. Platelets were isolated by
differential centrifugation.
Isolated blood platelets were labeled with 5-DOXYL-stearic acid (5-DS) or 12-DOXYL-stearic
acid (12-DS). Doxyl-stearic acids-stained platelets were incubated with Hcy (at final
concentrations of 10, 25 or 50 μmol/l), PBS (solvent for Hcy) hypoxanthine/xanthine oxidase,
NaOH and PBS (solvents for hypoxanthine and xanthine oxidase, respectively). After
incubations, EPR spectra were performed at room temperature and correlation time of rotational
diffusion c was calculated. ESR measurements were performed on ESP 300E X-band
spectrometer microwave frequency of 9.5 GHz; center field 337.5 mT; scan range 10 m;
modulation frequency 100 kHz; modulation amplitude 0.1 mT.
The isolated platelets were preincubated with Hcy (or PBS). Bovine heart cytochrome c was
added immediately after initiating of the incubation with Hcy in order to trap short-living oxygen
peroxide molecules. The concentration of generated superoxide anion radicals was estimated on
the basis of the molar extinction coefficient.
Results: Decrease of values of correlation time for rotational diffusion (τc) estimated for
membranes of intact homocysteinylaeted blood platelets stained with 5-DS spin has been
observed for all tested Hcy concentrations. However, the statistically significant reduction in τc
has been noted only for platelets treated with Hcy at concentration of 25 μmol/l.
Values of τc after incubation with Hcy were reduced in the case of platelets stained with 12-DS
spin tracer. Hcy at 10 μmol/l concentration reduced the mean value of τc 1.7, whereas 25 and 50
μmol/l concentrations decreased rotational time of correlation 1.8 and 1.5 times to control probes.
Hcy appeared as potent superoxide anion inducer only when used at concentration of 25 µmol/l
in comparison to PBS-treated platelets. At all other tested concentration Hcy-induced changes in
the concentration of superoxide anion remained statistically insignificant.
Conclusions: Hcy action on blood platelets is associated with membrane fluidization, especially
in deeper, hydrophobic regions of platelet membrane. On the base of preliminary, ongoing
experiments we preclude that superoxide anion generated during homocysteinylation of blood
platelets is probable mediator membrane fluidization.
Funding:This research was supported by the grant from the National Science Center (Cracow,
Poland), No. UMO 2012/07/N/NZ1/03140, funds from the Medical University of Lodz (Poland),
No. 502-03/6-020 01/502-64-058 and partially by the funds from the Polish Society of Metabolic
Diseases (Lodz, Poland).
61
IV FORUM EMR-PL 27-29.VI. 2016
Poster XX
THEORETICAL INVESTIGATIONS OF THE SPIN HAMILTONIAN PARAMETERS
AND THE LOCAL STRUCTURE OF Co2+
IONS IN PbMoO4 CRYSTAL
D. Piwowarska1, P. Gnutek
1, C. Rudowicz
1
1 Institute of Physics, West Pomeranian University of Technology, Al. Piastów 17, 70–310 Szczecin, Poland
In the present work, we employ the superposition model (SPM) analysis [1] for
determination of the zero-field splitting parameters (ZFSPs) [2] as well as the crystal field
parameters (CFPs) [3,4] for Co2+
ions doped into PbMoO4 crystal. The SPM calculations
utilize the structural data on the local environment around the dopant ions. Two structural
models are considered to predict CFPs and independently ZFSPs for Co2+
ions in PbMoO4 in
order to better to match the calculated ZFSPs with experimental ones measured by electron
paramagnetic resonance (EPR). The results enable to confirm the structural distortions in the
PbMoO4 lattice induced by doping Co2+
ions and discern between different environments: (i)
deformed dodecahedral 8-fold coordinated sites (Co2+
ions substituting for Pb2+
sites in the
host crystal) and (ii) deformed tetrahedral 4-fold coordinated sites (Co2+
ions replacing Mo6+
ions). The local distortion angles Δθ1 and Δθ2 in the vicinity ion Co2+
doped in PbMoO4 are
obtained. The experimental data are analyzed within the framework of the CF (or ligand field)
theory for the two Co2+
complexes in PbMoO4. Illustrative preliminary results are presented in
Table 1.
Table 1. Parameters for the 4-fold coordinated Co
2+ complexes in PbMoO4 crystal.
Calculated ZFSPs (This work ) Experimental spin
Hamiltonian parameters [5]
HS S=3/2 S=1/2
Complex Principal g-tensor
values (gx, gy, gz) D [cm
-1] E [cm
-1]
Principal g-tensor values
(g’x, g’y, g’z)
Co2+(α)
(1.99, 2.84, 2.51) 41.95 2.89
(6.26, 4.47, 1.97)
Co2+(β)
(1.72, 3.30, 1.79) 41.05 3.53
(7.41, 3.10, 1.69)
Calculated ZFSPs [6] Experimental spin
Hamiltonian parameters [6]
Co2+
doped
PbWO4 (2.10, 2.82, 2.52)
41.37
2.87 (6.20, 4.50, 2.07)
Acknowledgments We gratefully acknowledge the research grants from the Polish National Science Center: DEC-
2012/04/M/ST3/00817.
References [1] D.J. Newman, B. Ng, Superposition model, in: D.J. Newman, B. Ng (Eds.), Crystal Field Handbook,
Cambridge University Press, Cambridge (2000), 83-120.
[2] C. Rudowicz, M. Karbowiak, Coord. Chem. Rev., 287, (2015) 28.
[3] C. Rudowicz, Magn. Res. Rev. 13 (1987) 1.
[4] C. Rudowicz, S.K. Misra, Appl. Spectrosc. Rev. 36, 11 (2001).
[5] D. Piwowarska, A. Ostrowski, I. Stefaniuk, S. M. Kaczmarek, C. Rudowicz, Optical Materials 35 (2013) 2296.
[6] M.C. Chen, J.O. Artman, Phys. Rev. B 187 (1969) 723.
62
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXI
THE STUDY OF FREE RADICALS IN THE ENRICHED PEAT OF SPENT OIL – EPR
TECHNIQUE
B. Pytel1, K. Najwer
2, I. Pisarek
2, R. Szatanik
1, I. Mrówka
1
1Institute of Physics, Opole University, Opole, Poland
2Department of Land Protection, Opole University, Opole, Poland
The aim of the study was to determine the amount of free radicals and to understand the
role of Pleurotus ostreatus in the transformation of organic compounds in peat contaminated
with spent oil. An important part of our study was also to determine the degree of oyster
growing as a function of the effect of contamination in time. The technique of electron
paramagnetic resonance (EPR) was used, which is a non-invasive technique that requires a
small amount of the biological material for measurements. Tests were made at a constant
temperature of 22 ± 10C. Operating parameters of EPR spectrometer were: sweep range
ΔH=20mT, amplitude modulation ΔH=0.08mT, time constant Δt = 0.3s, sweep time t = 128s,
the center of the field H0 = 339.0 mT. The weight of each sample was 0.08 ± 0.002 g.
Fig. 1. Changes of the amplitude spectra: a) peat (without contaminants) with Pleurotus ostreatus, b) peat
contaminated of spent oil with Pleurotus ostreatus
Based on the study, the coefficient g for the measurements ranged close to a value of 2, which
indicates the presence of unbound free radical compounds. After 49 days of the experiment,
samples containing peat and Pleurotus ostreatus, the number of free radicals was slightly
decreased. This may show the possibility of organic matter transformation by Pleurotus
ostreatus and the involvement of free radicals in the structure of humic substances. At the same
time, in the samples containing peat contaminated with spent oil the opposite trend was
observed. A significant increase of free radicals in the analyzed samples can confirm the
degradation of Pleurotus ostreatus and the harmful effects of pollution from spent oil on the
growth of oyster and the effect of biological activity reduction in used peat. In the case of
control samples containing peat contaminated with spent oil (without Pleurotus ostreatus),
after 49 days of the experiment, no significant changes in the content of free radicals was
observed, which indicates that the Pleurotus ostreatus can be involved in transformation
processes of the organic matter contaminated with xenobiotics, including spent oil.
a) b)
63
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXII
FERROMAGNETIC RESONANCE STUDY OF HIGHLY CHROMIUM DOPED CdTe
ALLOY
I. Stefaniuk1, I. Rogalska
1 B. Cieniek
1
1 Faculty of Mathematics and Natural Sciences, University of Rzeszow, 1 Pigonia Str., 35-959 Rzeszow, Poland
The Cr- based DMS are also attractive for study due to the interesting connection, both
for semiconductor and magnetic physics resulting in future applications in spintronics [1]. In
the present work a CdTe alloy doped with relatively high concentration of chromium (8%) was
studied. This paper is extension of the work [2]. The EMR measurements at temperature range
from 95 K up to 380 K using the X-band ELEXSYS Bruker E 580 spectrometer were
performed. In addition, the measurements of ED EPR were also performed. The obtained
representative FMR spectra are shown in Fig. 1. The most interesting magnetic properties were
noticed for the sample in the vicinity of room temperature.
Ferromagnetism and probably antiferromagnetism properties correlated to changes induced by
temperature were observed simultaneously.
Fig. 1. Representative FMR spectra of Cd1-xCrxTe alloy at various temperatures in K
References [1]. W. Dobrowolski, J. Kossut, T. Story, II-VI and IV-VI diluted magnetic semiconductors–new bulk materials
and low-dimensional quantum structures, in K.H.J. Buschov (ed), Handbook of magnetic materials, Amsterdam
2003
[2]. I. Stefaniuk, M. Bester, I.E. Lipiński, Journal of Physics: Conference Series 30, (2006) 339 – 343
0 1000 2000 3000 4000 5000 6000
EPR
sig
nal
[arb
.u.]
Magnetic field [Gs]
220
225
230
235
240
245
250
255
260
265
270
275
280
285
290
295
300
305
315
320
64
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXIII
RELATION OF TOTAL POLYPHENOL AND FLAVONOID CONTENTS TO
ANTI-RADICAL PROPERTIES AND STABILITY OF TINCTURES OF
GEISSOSPERMUM RETICULATUM: CHEMOMETRIC ANALYSIS
AND LAG PHASE EPR
J.J. Sajkowska-Kozielewicz1, K. Gulik, K. Makarova
1, K. Paradowska
1
1 Department of Physical Chemistry, Medical University of Warsaw, Warsaw, Poland
Native people of Amazon region widely use tinctures from the bark of Geissospermum
species for numerous medicinal purposes. These tinctures exhibit antioxidant, anti-tumoral,
anti-malarial, anti-bacterial and nociceptive activities. [1] However, there is a lack of
physicochemical description of traditional remedies of Geissospermum reticulatum.
The aim of this research was to determine total phenolic and flavonoid contents of three
tinctures of G. reticulatum barks and evaluate their anti-radical activities and stability.
Three samples of barks were collected in Peruvian Amazonia. Total polyphenol (TP) and
flavonoid (TF) contents were defined by spectrophotometric methods. The obtained values
were interpreted by artificial neural networks (ANN) to find the most beneficial conditions for
tinctures. Their stability were assessed using lag phase electron paramagnetic resonance (EPR)
with α-(4-pyridyl-1-oxide)-N-tert-butylnitrone (POBN) spin trap. The ferric reducing ability of
plasma (FRAP) assay, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test using
EPR spectroscopy and the fluometric oxygen radical absorbance capacity (ORAC) assay were
applied to study anti-radical properties of tinctures. The Principal Component Analysis (PCA)
was employed to relate contents and properties.
All tinctures have shown the maximum of TP between 14-20 weeks of maceration, whereas the
maximum of TF was between 25-30. However, our data suggest that TP and TF contents do
not explain completely anti-radical activities. Results from the lag phase studies at 60 C
demonstrated that the stability of tinctures were related to TP content. Thus, samples with 550-
800 mg GAE/kg were more stable than those with higher TP contents.
The most beneficial conditions for tinctures from bark depends on aimed final products, i.e.
maximum of polyphenols or flavonoids and long-term stability. Further studied about content
and storage conditions are needed.
References [1] M. Reina, W. Ruiz-Mesia, M. López-Rodríguez, L. Ruiz-Mesia, A. González-Coloma and R. Martínez-Díaz,
Journal of natural products 75(5), (2012) 928-934.
65
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXIV
EMR DATA ON HIGH-SPIN Mn3+
(S = 2) IONS IN MnTPPCl COMPLEX
MODELLED BY MICROSCOPIC SPIN HAMILTONIAN APPROACH
K. Tadyszak1, C. Rudowicz
2,3
1 NanoBioMedical Centre, Adam Mickiewicz University, Poznań, Poland
2 Visiting Professor: Faculty of Chemistry, A. Mickiewicz University, Poznań, Poland
3 On leave of absence from: Institute of Physics, West Pomeranian University of Technology Szczecin, Poland
Due to the recent advances in the high-magnetic field and high-frequency EMR (HMF-
EMR) techniques, for references, see, e.g.[1,2]
an increasing number of experimental zero field
splitting (ZFS) and Zeeman electronic (Ze) parameter sets[1,2]
for 3d4 and 3d
6 (S=2) ions have
become available in literature in recent decades. The S = 2 ions, e.g. Fe2+
, Mn3+
, and Cr2+
,
usually exhibit large and very large ZFS[3,4]
, hence the HMF-EMR techniques are indispensable.
The availability of HMF-EMR data offers a comprehensive testing of the reliability of the
package MSH/VBA[3,4]
, which enables modelling of the spin Hamiltonian (SH) parameters
based on the microscopic SH (MSH) approach. The MSH expressions for the ZFS and Ze
parameters were developed up to fourth-order perturbation theory for studies of 3d4 and 3d
6
ions with spin S = 2 at orthorhombic and tetragonal symmetry sites in crystals, which exhibit
an orbital singlet ground state arising from the ground 5D multiplet
[7,8].
The SH parameters experimentally determined by HMF-EMR may be corroborated or
otherwise by theoretical modelling using either semiempirical methods or the density
functional theory (DFT) and ab initio methods. By bridging the gap between the two types of
methods the predictive power of model calculations may be increased. To this end
semiempirical modeling utilizing the package MSH/VBA is carried out for high-spin (S = 2)
manganese (III) 3d4
ion in complex of tetraphenylporphyrinato manganese (III) chloride
(MnTPPCl)[9]
. Calculations of the ZFS and Ze parameters are carried out for wide ranges of
values of the microscopic parameters. This enables to examine the dependence of the
theoretically determined ZFS parameters q
kb (in the Stevens notation) and the Zeeman factors
gi on the spin-orbit (λ), spin-spin () coupling constants, and the ligand-field energy levels (Δi)
within the 5D multiplet. The results are presented in suitable tables and graphs. The values of λ,
, and Δi best describing Mn(III) ions in MnTPPCl are determined by matching the theoretical
SH parameters and the experimental ones. Investigations of the role of the fourth-rank ZFS
parameters qb4 existing for S
~= 2
[5-7], which are often omitted in experimental studies, and the
(spin-spin) - related contributions to ZFSPs are now under progress. Illustrative preliminary
results will be presented.
Acknowledgments We gratefully acknowledge the research grants from the Polish National Science Center: DEC-
2012/04/M/ST3/00817 (CZR) and UMO-2014/15/B/ST4/04946 (KT).
References [1] T. Sakurai, K. Fujimoto, R. Goto, S. Okubo, H. Ohta, Y. Uwatoko, J. Magn. Reson. 223 (2012) 41.
[2] J. Telser, J. Krzystek, A. Ozarowski, J. Biol. Inorg. Chem. 19 (2014) 297.
[3] C. Rudowicz, M. Karbowiak, Coord. Chem. Rev. 287 (2015) 28.
[4] C. Rudowicz, S.K. Misra, Appl. Spectrosc. Rev. 36 (2001) 11.
[5] C. Rudowicz, H.W.F. Sung, J. Phys. Soc. Japan 72 Supplement B (2003) 61.
[6] M. Zając, I. E. Lipiński, and C. Rudowicz, J. Magn. Mag. Mat. 401 (2016) 1068.
[7] C. Rudowicz, H.W.F. Sung, Physica B 337 (2003) 204.
[8] C. Rudowicz, H.W.F. Sung, Manual for the Package MSH/VBA, unpublished (2004).
[9] J. Krzystek, J. Telser, et. al., Inorg. Chem., 31 (1999) 6121.
66
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXV
MAGNETIC DEFECTS IN Nb2SbVO10
J. Typek1, G. Zolnierkiewicz
1, M. Bobrowska
1, M. Piz
2, E. Filipek
2
1 Institute of Physics, West Pomeranian University of Technology, Szczecin, Poland
2 Department of Inorganic and Analytical Chemistry, West Pomeranian University of Technology, Szczecin,
Poland [email protected]
Nb2VSbO10 in powder form has been synthesized by a standard solid-state reaction
method [1]. To study its magnetic properties the dc magnetisation measurements using an
MPMS-7 SQUID magnetometer and EPR measurements performed on a conventional X–band
Bruker E 500 spectrometer were carried out (Fig. 1). From the nominal valence of ions forming
the Nb2VSbO10 structure it follows that the compound should display only diamagnetic
properties. Surprisingly, various types of magnetic defects (isolated ions, pairs and clusters)
have been detected. Comparison with reference sample allowed to calculate the equivalent
number of defect V4+
ions to reach 5% of all vanadium ions (EPR method) or 6.7 %
(isothermal magnetisation). The last method points out to the presence of other paramagnetic
ions in Nb2VSbO10 as well as pairs and clusters of ions.
3.0 3.5 4.0
-8
-6
-4
-2
0
2
4
6
8
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
40
60
80
100
120
140
160
180
200
EP
R a
mplit
ude [arb
.units]
Magnetic field [kOe]
4 K
290 K
(A)
0 1 2 3 4
0.00
0.02
0.04
0.06
0.08
0.10
Temperature [K]
Magnetic field [T]
290 K
60 K
10 K
Magnetization [
/f.u
.]
2 K
(C)
0 50 100 150 200 250 3000
1
2
3
4
5
EP
R inte
gra
ted inte
nsity [arb
. units]
T0L=-1.1 K
T0H=-85 K
(B)
0 50 100 150 200 250 3004
6
8
10
12
14
16
18
20
700 Oe 1 kOe
70 kOe
70 kOe
1 kOe
700 Oe
Temperature [K]
(D)
[10
3m
olO
e/e
mu]
[10-6
em
u/m
olO
e]
Recip
rocal E
PR
inte
gra
ted inte
nsity [arb
. units]
Fig. 1. (A) EPR spectra of Nb6Sb3VO25 recorded at 4 and 290 K; (B) Temperature dependence of EPR
integrated intensity (left axis) and reciprocal integrated intensity (right axis); (C) Isothermal magnetisation
registered at four different temperatures; (D) Temperature dependence of magnetic dc susceptibility (left
axis) and reciprocal dc magnetic susceptibility (right axis).
References [1] E. Filipek, M. Piz, J. Therm. Anal. Calorim. 101 (2010) 447.
67
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXVI
INTERACTION BETWEEN SPIN – LABELED Fe3O4 NANOPARTICLES AND
HUMAN BLOOD STUDIED BY EPR METHOD
K. Urbaniak1, B. Dobosz
1, R. Krzyminiewski
1, T. Kubiak
1, J. Kurczewska
2,
G. Schroeder2
1 Faculty of Physics, Adam Mickiewicz University, Poznań, Polska
2 Faculty of Chemistry, Adam Mickiewicz University, Poznań, Polska
Magnetic nanoparticles because of their specific structure give many medical
applications based mostly on functionalization of their surface. Usually such processes are
carried out with help of medicines or spin labels which can be successfully used in clinical
therapy and diagnostics. Nanoparticles are covered with biodegradable polymers with low
toxicity. Polymers increase biocompatibility of nanoparticles, improve stability in solutions,
prevent agglomeration and make possible to attach different ligands. Nanoparticles can serve
as a contrast in magnetic resonance imaging, they also give prospects for cancer therapy with
hyperthermia method or for use as medicines in targeted drug delivery.
The subject of research was the behavior of functionalized magnetite nanoparticles
Fe3O4 in aqueous solution, human blood and human blood serum. Magnetite nanoparticles
were labeled with 4-Amino-TEMPO and coated with chitosan. Measurements were conducted
using electron paramagnetic resonance EPR with spectrometer working on X-band. Samples
containing magnetite nanoparticles in different conditions were subjected to field cooling
process and frozen in the temperature of 130 K. Next EPR spectra for each of three samples
were recorded in the temperatures from 130 to 230 K in two orientations of samples in the
magnetic field: 0O and 90
O.
From EPR spectra of such nanoparticles it is possible to obtain two sources of
information. First is the broad line from magnetic core, second one is received from TEMPO
attached to the core. For each spectrum characteristic spectroscopic parameters have been
calculated (g factor and peak to peak line width ∆H) and the dependence between them and
temperature was shown in the appropriate graphs. For TEMPO spectra was determined so
called correlation time which gives the information about the dynamics.
References [1] B. Dobosz, R. Krzyminiewski, G. Schroeder, J. Kurczewska, Journal of Physics and Chemistry of Solids 75
(2014) 594-59
[2] R. Krzyminiewski, T. Kubiak, B. Dobosz, G. Schroeder, J. Kurczewska, Current Applied Physics 14 (2014)
798-804
[3] T. Kubiak, R. Krzyminiewski, B. Dobosz, G. Schroeder, J. Kruczewska, M. Hałupka-Bryl, Acta Bio-Optica et
Informatica Medica Inżynieria Biomedyczna, vol.21, nr1 (2015) 9-15
[4] J. Chomoucka, J. Drbohlavova, D. Huska, V. Adam, R. Kizek, J. Hubalek, Pharmacol, Res. 62 (2010) 144-149
68
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXVII
UV-INDUCED RADICALS IN STATINES – LIPID-LOWERING MEDICATIONS
M. Wencka1, S. van Doorslaer
2, J. Mielcarek
3
1 Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland
2 Department of Physics, University of Antwerp, Wilrijk, Belgium
3 Department of Inorganic and Analytical Chemistry, Poznań University of Medical Sciences, Poznań, Poland,
Statins act by competitive inhibition of the reductase, 3-hydroxy-3-methylglutaryl-
coenzyme A (HMG-CoA), an enzyme regulating of cholesterol synthesis in the cell. As a result
of their action is blocked conversion of HMG-CoA to mevalonic acid, which leads to a
reduction of the intracellular synthesis of cholesterol and low density lipoprotein (LDL).
Statins reduce LDL cholesterol by 30-50%, triglycerides by 10-15% and increase the
concentration of cholesterol in HDL by 5-8%. Statins are not a homogenous group of drugs
have different properties lipo- and hydrophilic, which determine the selectivity, affinity and
tissue penetration. Pravastatin and fluvastatin are characterized by a special hydrophilicity,
while lovastatin, simvastatin and atorvastatin, are characterized by a relative lipophilic. Statins
possess different pharmacological and pharmacokinetic properties. In recent years, statins have
been widely used in the prevention and treatment of atherosclerosis and its complications and
currently represent the most widely used group of drugs modifying blood lipids. The basic
mechanism of action has been very well understood. But today, statins are no longer seen as a
lipid-lowering drugs. Recent reports also indicate their pleiotropic properties and great
potential use of statins in the treatment of other diseases. Proven and observed for several
years, the process of expanding the indications for their administration - make that statins are a
very fast growing group of drugs. For inhibition of HMG-CoA is required the presence of
certain chemical moieties, spatially distributed in a well-defined distance; the remaining part of
the molecule may exhibit a large variation in the structure, without affecting the effectiveness
of the drug. This allows a broad modification of the molecule and the synthesis of new
compounds, leading to a drugs more and more targeted properties. Currently on the polish
pharmaceutical market there are seven statins differing in chemical structure, potency and
pharmacokinetic profile.
The aim of our studies was to investigate the photochemical stability of selected HMG-CoA
reductase inhibitors including atorvastatin, fluvastatin, lovastatin, pitavastatin, pravastatin,
rosuvastatin and simvastatin. Photodegradation of drugs was monitored by means of the EPR
method (X- and W- band Bruker EPR spectrometers). Photochemical experiments were
conducted according to the Document International Conference on Harmonization (ICH Q1B)
recommendations, currently in force in studies of photochemical stability of drugs and drug
products. Statins in crystalline form were irradiated using high pressure UV Hg-lamp equipped
with Wood’s filter of 365 nm at the maximum of wavelength. For 60 min of irradiation that
corresponds to 750 J of energy we created 1015
light-generated radicals in one gram of
lovastatin that is the most light-stable statin. The easiest degradable statin is the pitavastatin
with 6 1016
radicals/g. We were able to distinguish three types of UV-induced radicals in
pitavastatin and fluvastatin. The first Lorentzian-type radical is characterised by gII =
2.00195(5) and g = 2.0050(1) with BppII
= 0.65 mT and Bpp
= 1.05 mT, the second – with
less precisely assessed parameters of gII = 2.0080(10) and g = 2.0022(5) and the third one
with gII = 2.0021(5) and g = 2.0043(5) with BppII
= 1.2 mT and Bpp
= 1.05 mT. Relatively
big anisotropies of g-factor without hyperfine structure might be a signature confirming
interaction without protons. Considering our results supported by crystal structure of statins we
suggest that UV-generated radicals are localized on oxygen atoms.
69
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXVIII
Cu2+
DOPED MOLECULAR SIEVES FOR MONITORING STRUCTURAL CHANGES
AND GUEST-HOST INTERACTIONS
A. Zalewska1, A. Jankowska
1, A. Skalska
1, A. Ostrowski
2, S. K. Hoffmann
2, S. Kowalak
1
1 Faculty of Chemistry, Adam Mickiewicz University, Poznań, Poland
2 Institute of Molecular Physics, Polish Academy of Sciences, Poznań, Poland
The molecular sieves consist of various families of porous materials (zeolites, zeotypes,
ordered mesoporous materials, MOF etc.) indicating an uniform pore system in given type,
regardless of different chemical composition. During recent decades they attained enormous
importance in many practical applications. The composites comprising the host (molecular
sieve) – guest (entrapped molecules) systems are particularly interesting and promising for
numerous applications (e.g. sensors, optical, microelectronic devices, etc.). The advanced and
detailed study of these systems require whole arsenal of modern scientific tools and ESR
spectroscopy is one of the most sensitive and efficient. However, many types of the molecular
sieves and the incorporated guest compounds do not show any paramagnetic properties and
cannot be directly studied by means of this technique. Nevertheless, a doping of the studied
material with paramagnetic agent such as Cu2+
either to guest or to host allows to investigate
the interaction between them and the structural details of resulted species.
The following study presents the ESR study on imidazole (Him) embedded into
zeolites, zeotypes, and ZIF materials in order to assess the proton electric conductivity of
resulted composites. The applied diamagnetic matrices were doped with Cu2+
cations either
upon their synthesis or by means of post–synthesis modification. The ESR signals due to Cu2+
are very sensitive and they clearly reflect the interaction with the guest Him molecules. For
instance the spectra indicate a significant difference in spectroscopic parameters gII and AII in
the Cu2+
doped material [Zn(im)2]n before (A) and after (B) replacing of the initial guest –
pyridine with imidazole. The above spectral changes reflect the structural matrix
transformations resulted from the guest replacement and illustrated in XRD.
70
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXIX
SPIN TRAP AND SPIN PROBE ESR FOR THE OPTIMIZATION OF ANTIOXIDANT
PROPERTIES OF HERBAL BATHING SALTS
K. Zawada1, K. Makarova
1, D. Kowalska
1
1 Faculty of Pharmacy with the Laboratory Medicine Division, Medical University of Warsaw, Warsaw, Poland
Traditionally, bathing with salts has been viewed as relaxing and healing. Herbal
extracts have been added to the salts in order to increase their therapeutic properties. This
increase is partly due to the antioxidant properties of herbs. In this work we optimized the
extraction condition of 3 herbal materials (lavender flower, melissa and birch leaf) in order to
achieve maximum antioxidant properties. The lipid membrane permeability of herbal extracts
with the highest antioxidant activity was also determined. Then we prepared bathing salts
(from Dead Sea or Bochnia Salt Mine) based on optimized extracts, and determined their
antioxidant properties and the influence on lipid membrane permeability.
The antioxidant activity was studied with DPPH–ESR test as well as by spin trap ESR using
Fenton reaction both in the absence and in the presence of model lipids (DOPC), with PBN as
a spin trap. The influence on lipid membrane permeability of herbal extracts and herbal salts
was studied with the spin probe ESR in the range of 293-323 K. DOPC liposomes were used as
a model lipid bilayer, and DTBN as a spin probe.
The optimal conditions for the extraction of herbal materials were: 15 minutes extraction time
and temperature of 333 K. The order of antioxidant activity of herbal salts depended on the
presence or absence of lipids. The lowest permeability was observed for extracts of melissa and
birch leaf, followed by corresponding herbal salts based on Bochnia Salt Mine salt, and it was
lower than in the reference system. On the other hand, lavender extract increased the
permeability of the model membrane, and lavender salts decreased the permeability. Thus,
even though the lavender extract did not show the highest antioxidant activity in the Fenton
reaction and DPPH test, due to better permeability it showed the highest antioxidant activity in
the lipid phase which is desired for cosmetic use.
In conclusion, combination of permeability studies with antioxidant studies in the presence of
model lipids could be potentially used for optimization of other types of herbal bath salts.
71
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXX
EPR STUDIES OF THE FREE RADICAL SCAVENGING ACTIVITY
OF SIMVASTATIN
M. Zdybel1, B. Pilawa
1, E. Chodurek
2
Medical University of Silesia, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec,
1Department of Biophysics,
2Department of Biopharmacy, Jedności 8, 41-200 Sosnowiec, Poland
The interactions of simvastatin with free radicals were examined by an X-band (9.3
GHz) EPR spectrometer. The influence of temperature and UV-irradiation on the free radical
scavenging activity of simvastatin was determined. The model DPPH (1,1-diphenyl-2-
picrylhydrazyl) free radicals with unpaired electrons localized on nitrogen (N) atom [1,2] were
used in this study. DPPH is the standard in EPR studies of the antioxidative samples [3,4]. EPR
spectra of DPPH in contact with simvastatin were compared with those of DPPH - the
reference. The samples were prepared in ethyl alcohol solution. The drug storage at room
temperature, and it was heated in the hot air oven with air circulation of Memmert Firm
(Germany) at temperatures: 37 oC, 40
oC, and 42
oC. UVA-irradiation (λ: 315-400 nm) was
done by the Medisun 250 lamp (Germany) equipped with 4 radiators with power of 20 W. The
spectra of DPPH were measured by EPR spectrometer of Radiopan Firm (Poznań, Poland) and
by the data acquisition system - the Rapid Scan Unit of Jagmar Firm (Kraków, Poland).
The antioxidative character was stated for the original - untreated simvastatin, the heated
and UV-irradiated samples. The tested drug quenched the EPR lines of DPPH free radicals.
The kinetics of the interactions free radicals - simvastatin were tested as the correlations
between amplitudes (A) of DPPH EPR lines and contact time of DPPH with the drug samples.
The changes of the scavenging activity of simvastatin treated by the higher temperatures and
UV-irradiation were evaluated. The kinetic modification by the physical factors was obtained.
The practical applications of the results in medicine of tumors were discussed.
Acknowledgements
This study was financially supported by Medical University of Silesia in Katowice.
References [1] G. Bartosz, Druga twarz tlenu. Wolne rodniki w przyrodzie, PWN, Warszawa, (2006).
[2] G. Tirzitis and G. Bartosz, Acta Biochimica Polonica 57, (2010) 139-142.
[3] N.D. Yordanov and A. Christova, Applied Magnetic Resonance 6, (1994) 341-345.
[4] P. Molyneux, Songklanakarin Journal of Science of Technology 26, (2004) 211-219.
72
IV FORUM EMR-PL 27-29.VI. 2016
PosterXXXI
THE INFLUENCE OF SIMVASTATIN ON FREE RADICALS IN HUMAN
MELANOMA MALIGNUM CELLS – EPR EXAMINATION
M. Zdybel1, E. Chodurek
2, B. Pilawa
1
Medical University of Silesia, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec,
1Department of Biophysics,
2Department of Biopharmacy, Jedności 8, 41-200 Sosnowiec, Poland
Free radicals in different types of human melanotic cells (Fig. 1) exposed to simvastatin
were examined by electron paramagnetic resonance (EPR) spectroscopy. Simvastatin showed
cytotoxic and cytostatic effect in numerous cancer cell lines [1]. The effect of simvastatin
doses on properties and concentration of free radicals in the human melanoma cells was
determined. The human melanoma malignum cells were purchased from LGC Promochem
(Łomianki, Poland). Simvastatin was obtained from Sigma-Aldrich.
Fig. 1. A-2058 cell lines. Magnification 200x.
Melanoma malignum cells contain paramagnetic melanin polymer [2]. Paramagnetic centers of
melanin are mainly responsible for the EPR spectra of melanotic cells [2-4].
o-Semiquinone free radicals were found in the tested tumor cells. All the EPR spectra of the
cells were the very broad lines.
The simvastatin changed the free radical concentration in the melanotic tumor cells. Probably
o-semiquinone melanin free radicals take a part in the formation of the complexes between
simvastatin and the melanin polymer in the pathological cells. The role of o-semiquinone free
radicals in binding of different drugs to melanin was stated earlier [5,6]. The changes in free
radical system of human melanoma malignum cells after treatment by simvastatin depended on
type of cells and dose of this drug. The practical application of the EPR results in therapy of
tumor were discussed.
Acknowledgements
This study was financially supported by Medical University of Silesia in Katowice.
References [1] A. Saito, N. Saito, W. Mol, H. Furukawa, A. Tsutsumida, A. Oyama, M. Sekido, S. Sasaki and Y. Yamamoto,
Melanoma Research 18, (2008) 85-94.
[2] M. Zdybel, E. Chodurek and B. Pilawa, Acta Poloniae Pharmaceutica – Drug Research 71, (2014) 1066-1072.
[3] E. Chodurek, M. Zdybel, B. Pilawa and Z. Dzierżewicz, Acta Poloniae Pharmaceutica – Drug Research 69,
(2012) 1334-1341.
[4] E. Chodurek, M. Zdybel and B. Pilawa, Journal of Applied Biomedicine 11, (2013) 173-185.
[5] M. Otręba, M. Zdybel, B. Pilawa, A. Beberok, D. Wrześniok, J. Rok and E. Buszman, European Biophysics
Journal 44, (2015) 359-365.
[6] B. Wiernek, B. Pilawa, M. Zdybel, E. Buszman and D. Wrześniok, Journal of Applied Biomedicine 12, (2014)
161-169.
73
IV FORUM EMR-PL 27-29.VI. 2016
Poster XXXII
EPR/FMR STUDY OF nCoO/(1-n)ZnO (n=0.4, 0.5, 0.6 AND 0.7) NANOCOMPOSITES
N. Guskos1, G. Zolnierkiewicz
1, J. Typek
1, D. Sibera
2, U. Narkiewicz
2
1Institute of Physics, West Pomeranian University of Technology, Al.Piastow 48,70-311 Szczecin, Poland
2Institute of Chemical and Environment Engineering, West Pomeranian University of Technology, ul. Pulaskiego
10, 70-322 Szczecin, Poland
The EPR/FMR spectra of the nCoO/(1-n)ZnO nanocomposites (where the composition
index n=0.4, 0.5, 0.6 and 0.7) prepared by hydrothermal synthesis have been investigated.
XRD measurements of the obtained nanocomposites displayed peaks from ZnO, ZnCo2O4 and
weak lines attributed to Co(OH)2 phase containing Co2+
ions. With an increase of the index n
the decrease of ZnO phase was observed and the reflections from ZnCo2O4 compound were
more intense. SEM picture of 0.7CoO/0.3ZnO nanocomposite confirmed the presence of large
agglomerates of magnetic nanoparticles. Figure 1 presents FMR/EPR spectra taken at different
temperatures and the insets show EPR spectra of Co2+ ions at low temperatures. In general,
magnetic resonance spectra consists of two components, one derived from the Co2 +
ions (EPR)
which form a narrow resonance line at low magnetic fields and the other arising from magnetic
agglomerates (FMR) with appears as a very broad line. The former component is due to
Co(OH)2 phase and the later to ZnCo2O4 phase. In case of 0.6CoO/0.4ZnO nanocomposite the
FMR line is so broad it couldn’t be registered at our spectrometer (Fig. 1c).
0 2000 4000 6000 8000
-4
-2
0
2
4
0 500 1000 1500 2000 2500-40
0
40
80
120
160a)
d"/d
H [
Arb
. u
nit
s]
Magnetic field H [G]
60 K
70 K100 K
n = 0.4
17 K
13 K
7 K
4 K
0 2000 4000 6000 8000
-6
-5
-4
-3
-2
-1
0
0 1000 2000 3000
-10
0
10
20
30
40
b)
d"/d
H [
Arb
. u
nit
s]
Magnetic field H [G]
90 K
60 K
50 K
n = 0.5
4 K
7 K
13 K
17 K
0 500 1000 1500 2000 2500 3000-6
-3
0
3
6
9
12
15c)
d"/
dH
[A
rb.
un
its
]
Magnetic field H [G]
4 K
7 K
13 K
17 K
n=0.6
0 2000 4000 6000 8000-10
-8
-6
-4
-2
0
0 1000 2000
-4
-2
0
2
4
6
8
10
d)
d"/
dH
[A
rb.
un
its]
Magnetic field H [G]
70 K
55 K
45 K
35 K
n = 0.7
4 K
7 K
13 K
17 K
Fig. 1 FMR/EPR spectra of the nCoO/(1-n)ZnO nanocomposites: (a) n=0.4; (b) n=0.5; (c) n=0.6; (d) n=0.7.
The insets in (a), (b), and (d) show EPR spectra of Co2+
ions registered at low temperatures.
74
IV FORUM EMR-PL 27-29.VI. 2016
Names index
A
Abdullajanova, N., 42, 58
Akthar, W., 25
Anders, J., 25
Augustyniak-Jabłokow, M. A.,
20, 39, 40, 54
B
Badyła, A., 37
Bandosz, T., 34
Baranowski, M., 15, 16
Bednarski, W., 59
Behrends, J., 25
Bernasińska, J., 51
Biedunkiewicz, A., 19
Bilkova, I., 46
Bitiucki, M., 42
Blank, A., 25
Blonska-Tabero, A., 17
Bobrowska, M., 43, 66
Bodziony, T., 19
Boś-Liedke, A., 16, 44
Bujok, J., 50
C
Chiesa, M., 24
Chlewicki, W., 15, 16
Chodurek, E., 71, 72
Cieniek, B., 18, 45, 63
Coy, L. E., 52
Czechowski, T., 15, 16, 44
D
Danielska, P., 60
Decyk, P., 46
Detyna, J., 50
Dobosz, B., 31, 55, 67
Doorslaer, S., 68
Dubiel, Ł., 47
F
Fedaruk, R., 39
Figiel, P., 19
Filek, M., 32
Filipek, E., 43, 66
Frączek, Z. J., 48
Fuks, H., 49
G
Gałecka, K., 30, 50
Gieniusz, R., 58
Gnutek, P., 61
Grabowski, M., 51
Grzeszczuk-Kuć, K., 50
Gulik, K., 64
Guskos, N., 17, 73
Gwoździński, K., 51
Gwoździński, L., 51
H
Hara, S., 14
Hoffmann, S. K., 69
J
Jancelewicz, M., 16
Jankowska, A., 69
Jerzykiewicz, M., 27
Jezierska, J., 26, 27
Jurga, J., 15, 16
Jurga, K., 15
Jurga, S., 44
K
Kabacińska, Z., 16, 44, 52
Kaczmarek, S. M., 19, 49
Karbowiak, M., 38
Karolczak, K., 60
Katz, I., 25
Kedzia, P., 15
Kempiński, M., 34
Kempiński, W., 34, 35
Komorowska, M., 30, 50
Kowalak, S., 69
Kowalczyk, E., 51
Kowalska, D., 70
Kozanecki, M., 23
Krasowska, A., 53
Krupska, A., 54
Krzyminiewski, R., 31, 52, 55,
67
Kubiak, T., 55, 67
Kucharska, B., 49
Kurczewska, J., 31, 55, 67
Kurdziel, M., 32
Kuźma, M., 18, 36, 47
L
Łabanowska, M., 32
Leniec, G., 19, 49
Lips, K., 25
Łoś, S., 34, 35
M
Maćkowiak, M., 20
Makarova, K., 56, 64, 70
Malinowski, P., 15
Man, D., 57
Matuszak, Z., 33
Mavlyanov, S., 58
Maziarz, W., 47
Mazur, T., 24
Meier, C., 25
Michalski, J., 49
Mielcarek, J., 68
Mikoda, P., 30
Möser, J., 25
Mrówka, I., 57, 62
N
Najder-Kozdrowska, L., 46
Najwer, K., 62
Narkiewicz, U., 73
O
Ohmichi, E., 14
Ohta, H., 14
Okubo, S., 14
Olchowik-Grabarek, E., 42, 58
Oleszko, A., 30
Ostrowski, A., 59, 69
Ozarowski, A., 26, 27
P
Padlyak, B.V., 29
Paradowska, K., 64
Pieniążek, A., 51, 60
Pietrzyk, P., 21, 24, 28, 53
Pilarska, M., 17
Pilawa, B., 71, 72
Pisarek, I., 62
Piwowarska, D., 61
75
IV FORUM EMR-PL 27-29.VI. 2016
Piz, M., 43, 66
Podolska-Serafin, K., 53
Popovych, V. D., 18
Potera, P., 37
Pytel, B., 57, 62
R
Radoń, M., 24
Reger, D. L., 26
Rogalska, I., 63
Rudowicz, C., 22, 23, 38, 61,
65
S
Sagan, P., 47
Sajkowska-Kozielewicz, J. J.,
64
Sakurai, T., 14
Samolej, A., 16
Schnegg, A., 25
Schroeder, G., 31, 55, 67
Sękowski, S., 42
Sibera, D., 73
Skalska, A., 69
Skop, N., 18
Skowyra, J., 56
Sobańska, K., 28
Sojka, Z., 21, 24, 28
Stefaniuk, I., 18, 37, 45, 47, 63
Strzelczyk, R., 20, 39, 54
Szatanik, R., 62
Szczepanik, P., 15
Szulc, P., 15
T
Tadyszak, K., 15, 16, 38, 39,
44, 65
Takahashi, H., 14
Trębińska, M., 56
Trybuła, M., 35
Trybuła, Z., 35
Turczyński, S., 48
Typek, J., 17, 43, 66
U
Urbaniak, K., 67
V
Virt, I., 45
W
Wach, P., 49
Wagner, D., 56
Wal, A., 47
Walawender, M., 44
Walski, T., 50
Waplak, S., 59
Wawer, I., 56
Wencka, M., 48, 52, 59, 68
Więckowski, A. B., 46
Wisz, G., 47
Witwicki, M., 27
Z
Zając, M., 22
Zalewska, A., 69
Zamaraeva, M., 42, 58
Zawada, K., 56, 70
Zdybel, M., 71, 72
Ziółek, M., 46
Zolnierkiewicz, G., 17, 43, 66,
73
76
IV FORUM EMR-PL 27-29.VI. 2016
Important places
Campus of the A. Mickiewicz University with marked route to the Faculty of Physics
The Campus Morasko (Campus of the A. Mickiewicz University) is located on the
north site of Poznań. The easiest way to get to the Faculty of Physics from the city centre is to
take tram (no. 12, 14, 15, or 16) in the direction ‘Sobieskiego’. The final stop (Osiedle
Sobieskiego) is marked at the plan above as Tramway terminal. Then take approximately 1 km
walk to the Faculty (entrance B), marked with red dots.
Faculty of Physics, Campus Morasko AMU
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IV FORUM EMR-PL 27-29.VI. 2016
Działyński Palace (PL - Pałac Działyńskich) is located on the old marked squere
Conference Dinner will be held in Działyński Palace in Poznań, a baroque palace built in 1773
– 1776.
The way to Działyński palace from Kupiec Poznański shoping centre
Direct conection between Campus Morasko and the city centre is made by the tram no
16. On the figure above the way to the Dzialyński palace is marked with red dots.
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IV FORUM EMR-PL 27-29.VI. 2016
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NOTES
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NOTES
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NOTES
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NOTES
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NOTES