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od 2020-09-20

Prof. UAM dr hab. Eugeniusz Szcześniak  | 1994-10 <> 2009-12

Profesor UAM

   WF UAM pokój: 135      +48 61-829-5238       szcz@amu.edu.pl

  6701414853  

Zainteresowania naukowe:
NMR i jego zastosowania do badania dynamiki i struktury materii skondensowanej. Stosowane techniki obejmują badania procesów relaksacji i widm różnych jąder oraz mikroobrazowanie magnetyczno rezonansowe

Publikacje      Projekty      Doktorzy      Magistrowie           Seminaria


57.

Czechowski T., Chlewicki W., Baranowski M., Jurga K., Szcześniak E., Szostak M., Malinowski P., Kędzia P., Szczepanik P., Szulc P., Wosiński S., Prukała W., Jurga J.

The magnet system for rapid scan electron paramagnetic resonance imaging and spectroscopy The magnet and gradient systems suitable for electron paramagnetic resonance imaging experiments at RF range are presented. The air-core magnet based on the Helmholtz design in the article has a unique conical shape. A comprehensive study regarding the coils adjustment providing for the maximum field homogeneity is given. The z gradient is a four-coil system (seventh order), the transverse gradients are Golay coils (fifth order), and the scan system is the Helmholtz coil (fourth order). The magnet generates continuously a field of 37 mT (370 G), and the orthogonal gradient coils are designed to yield 100 mT/m (10 G/cm). The experimental tests have shown that the field generated is homogeneous to ± 10 ppm in the 6 x 6 x 3 cm3 region (x/y/z), which is our field of interest, and to ± 50 ppm in the 8 x 8 x 4 cm3 region (x/y/z). The system has the potential to monitor temporal changes of oxygen concentration in biological samples.
(c) 2013 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 43B:2231, 2013

Concepts in Magnetic Resonance Part B - Magnetic Resonance Engineering, 43B, 22-31 (2013)

DOI: 10.1002/cmr.b.21228   (Pobrane:  2020-10-25)


56.

Kędzia P., Czechowski T., Baranowski M., Jurga J., Szcześniak E.

Analysis of uniformity of magnetic field generated by the two-pair coil system In this paper we use a simple analysis based on properties of the axial field generated by symmetrical multipoles to reveal all possible distributions of two coaxial pairs of circular windings, which result in systems featuring zero octupole and 32 pole magnetic moments (six-order systems). Homogeneity of magnetic field of selected systems is analyzed. It has been found that one of the derived systems generates homogenous magnetic field whose volume is comparable to that yielded by the eight-order system. The influence of the current distribution and the windings placement on the field homogeneity is considered. The table, graphs and equations given in the paper facilitate the choice of the most appropriate design for a given problem. The systems presented may find applications in low field electron paramagnetic resonance imaging, some functional f-MRI (nuclear magnetic resonance imaging) and bioelectromagnetic experiments requiring the access to the working space from all directions.

Applied Magnetic Resonance, 44(5), 605-618 (2013)

DOI: 10.1007/s00723-012-0427-5


55.

Kędzia P, Szcześniak E., Czechowski T., Baranowski M., Jurga J.

Patent - własność intelektualna rejestrowana prawnie

Magnetic field generating method for magnetic resonance tomography involves using two pairs of coils in which current flows in same direction and sense to generate magnetic fields of high uniformity within object examined NOVELTY - The magnetic field generating method involves using two pairs of coils (1,2) in which current flows in the same direction and sense to generate magnetic fields of high uniformity within an object examined. The coil pairs have the same radiuses (R1,R2). USE - Magnetic field generating method for magnetic resonance tomography. ADVANTAGE - Ensures simple generation of magnetic field of high uniformity at reduced power indispensable for operating the tomograph. Enables unambiguous establishing of all parameters which are indispensable for the design and manufacture of generating and compensating coils. Enables significant reductions of operating costs e.g. lower costs of shielding, lower values of current for generating higher values of magnetic fields, small sizes enabling easy access to the inside of the coil system, transverse, axial access to the uniform field region.
DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a magnetic field generating system.
DESCRIPTION OF DRAWING(S) - The drawing shows the explanatory view of a coil geometry

Patent Number: US2012200295-A1 ; EP2487500-A1 ; PL393899-A1 ; US8884621-B2, , (2012)

   (Pobrane:  2021-01-20)


54.

Baranowski M., Chlewicki W., Czechowski T., Jurga J., Jurga K., Kędzia P., Malinowski P., Szczepanik P., Szcześniak E., Szulc P.

Patent - własność intelektualna rejestrowana prawnie

System for determining concentrations of radicals projection by changing field frequency in high-frequency spatial-spectral imaging of EPR, has computer connected to power supply of constant magnetic field coil NOVELTY - The system has a radio frequency signal source whose input is connected to a first waveform generator and output is connected to an input of a bridge servo unit. An output of the bridge servo unit is connected to a first computer. An input and an output of the first waveform generator are connected to an I/O resonator. A second computer is connected to a second waveform generator. The second waveform generator is connected to a gradient coil. An output of the first computer is connected to power supply of constant magnetic field coil.
USE - System for determining concentrations of radicals projection by changing field frequency in a high- frequency spatial-spectral imaging of EPR.

Patent Number: PL402173-A1, , (2012)

   (Pobrane:  2021-01-20)


53.

Baranowski M., Chlewicki W., Czechowski T., Jurga J., Jurga K., Kędzia P., Malinowski P., Szczepanik P., Szcześniak E., Szulc P.

Patent - własność intelektualna rejestrowana prawnie

Method for determining projected concentrations of radicals, involves scanning magnetic field in imaging space, scanning space sinogram at constant amplitude of magnetic field, and determining concentrations of radicals by scanning field NOVELTY - The method involves scanning a magnetic field in an imaging space. An imaging space sinogram is spectrally scanned at a constant amplitude of the magnetic field between resonators. Concentrations of radicals are determined by scanning the magnetic field in the imaging space. USE - Method for determining projected concentrations of radicals.

Patent Number: PL402174-A1, , (2012)

   (Pobrane:  2021-01-20)


52.

Kędzia P., Szcześniak E., Jurga J., Jurga K., Czechowski T., Baranowski M., Szczepanik P, Szulc P., Malinowski P.

Patent - własność intelektualna rejestrowana prawnie

Method for producing longitudinal magnetic field gradient with high uniformity within test object, involves providing mixture of foliated graphite, nickel chloride, palladium chloride and ferric chloride in specific ratio as catalyst NOVELTY - The method involves providing a mixture of foliated graphite, nickel chloride, palladium chloride and ferric chloride in the ratio of 20:1:2.5 to be used as a catalyst.
USE - Method for producing longitudinal magnetic field gradient with high uniformity within a test object.
DESCRIPTION OF DRAWING(S) - The drawing shows a schematic illustration of a method for producing longitudinal magnetic field gradient with high uniformity within a test object.

Patent Number: PL397916-A1, , (2012)

   (Pobrane:  2021-01-20)


51.

Baranowski M., Czechowski T., Jurga J., Jurga K., Szcześniak E.

Patent - własność intelektualna rejestrowana prawnie

Method for obtaining images of electron relaxation time in electron paramagnetic resonance (EPR) tomography by measuring distribution of spin relaxation times of electron spins, involves NOVELTY - The method involves establishing time and repetition of set modulation in resonator (8) so as to obtain the projection of relaxation time. The amplitude value of EPR signals which is proportional to sample magnetization is established as measured in fast adiabatic transition condition in presence of magnetic field gradient with respect to swept condition stating that the modulation is performed by changing generator frequency or magnetic field. The value of relaxation time is determined for every point of recorded spectra using a preset formula.
USE - Method for obtaining images of electron relaxation time in EPR tomography by measuring distribution of spin relaxation time of electron spin, used for oncological treatment.
ADVANTAGE - The images of electron relaxation time in EPR tomography can be obtained effectively in presence of strong gradients and radicals with short relaxation time. The time value can be reduced by using smaller gradients or slow-rotating gradients with assigned rotation. Thus the measurement of the spin relaxation time can be measured quickly and precisely. The individual images can be combined into sequence of frames presenting real-time changes of oxygen concentration in selected tissue. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for system for enabling localization of cancerous lesion using electron paramagnetic resonance imaging system. DESCRIPTION OF DRAWING(S) - The drawing shows a block diagram illustrating the process for obtaining the images of relaxation time in EPR tomography.

Patent Number: EP2378281-A1 ; PL390887-A1, , (2010)

   (Pobrane:  2021-01-20)


50.

Zalewski T., Lubiatowski P., Jaroszewski J., Szcześniak E., Kuśmia S., Kruczyński J., Jurga S.

Scaffold-aided repair of articular cartilage studied by MRI Objective The objective of the study was to evaluate the ability of the noninvasive magnetic resonance techniques to monitor the scaffold-aided process of articular cartilage repair.
Materials and methods Defects of 4 mm in diameter and 3 mm in depth were created in right knees of 30 adolescent white New Zealand rabbits. Fourteen rabbits were implanted with poly(lactide-co-glycolic acid) (PLGA) scaffold trimmed to match the size and the shape of the defect (PLGA+ group). No procedure was applied to the remaining 16 animals (PLGA- group). Animals were sacrificed sequentially at 4, 12, and 24 weeks after the surgery and magnetic resonance T(2)-weighted images (400 MHz) of the dissected bone plugs at eight different echo times were taken to derive T(2) relaxation time. The images and the T(2) time dependencies versus the tissue depth were statistically analyzed. Histological results of bone plugs were evaluated using semiquantitative histological scales.
Results The results obtained for PLGA repair tissue were evaluated versus the PLGA- group and the healthy tissue harvested from the opposite knee (reference group), and compared with histological results (hematoxylin and eosin staining). The magnetic resonance images and T(2) relaxation time profiles taken 4 weeks after surgery for both the PLGA- and PLGA+ group did not reveal the tissue reconstruction. After 12 weeks of treatment T(2) time dependence indicates a slight reconstruction for PLGA+ group. The T(2) time dependence obtained for PLGA+ samples taken after 24 weeks of treatment resembled the one observed for the healthy cartilage, indicating tissue reconstruction in the form of fibrous cartilage. The tissue reconstruction was not observed for PLGA-samples.
Conclusion The study revealed correlation between magnetic resonance and histology data, indicating the potential value of using MRI and spatial variation of T (2) as the noninvasive tools to evaluate the process of articular cartilage repair. It also suggested, that the PLGA scaffold-aided treatment could help to restore the proper architecture of collagen fibrils.

Magnetic Resonance Materials in Physics, Biology and Medicine, 21(3), 177-185 (2008)

DOI: 10.1007/s10334-008-0108-4   (Pobrane:  2020-10-21)


49.

Lubiatowski P., Zalewski T., Gradys A., Kruczyński J., Jaroszewski J., Trzeciak T., Szcześniak E., Manikowski W.

Application of microscopic MR for evaluation of cartilage repair Magnetic resonance imaging is gold standard for noninvasive evaluation of articular cartilage damage and has been also used for monitoring cartilage repair. The aim of this study was to find correlation between histological microscopy and microscopic MR in evaluation of the repair of osteochondral defects in articular cartilage. Study was based animal model (rabbit). The cartilage repair process was evaluated histology and micro MR. Most of the defects were filled with fibrocartilage and fibrous tissue formed. Both methods were equally efficient to show repair tissue thickness, subchondral bone reconstruction and disintegration. Result of observation by both histological and MR microscopy and showed good correlation. Micro MR is promising evaluation tool for cartilage repair monitoring. Results of micro MR correlate well with standard microscopy.

Chirurgia Narządów Ruchu i Ortopedia Polska, 72(3), 193-9 (2007)

   (Pobrane:  2020-10-21)


48.

Krzaczkowska J., Szcześniak E., Jurga S.

Phase behaviour of dipalmitoylphosphatidylcholine/surfactant/water systems studied by infrared spectroscopy Phospholipids are the most important components of membranes taking part in stabilization of the functional structure of biological cells. The main aim of the present study is to determine the influence of selected antimicrobial surfactants on the phospholipids structure. The water solutions of dipalmitoylphosphatidylcholine (DPPC) in the presence of two quaternary ammonium surfactants: dodecyidimethyl(hexyloxymethyl)ammonium chloride (HMDDAC) and (decyloloxymethyl)dodecydimethylammonium chloride (DMDDAC) were studied using FTIR spectroscopy. The thermal behaviour of these systems was analyzed using spectral parameters of CH2 and C=O vibrations bands. We have observed a lowering of temperature corresponding to the main phase transition of the surfactant/DPPC systems due to disordering of the phospholipids structure by the surfactants and phospholipids interaction.
(C) 2006 Published by Elsevier B.V.

Journal of Molecular Structure, 794(1-3), 168-172 (2006)

DOI: 10.1016/j.molstruc.2006.02.003   (Pobrane:  2020-10-21)


47.

Kuśmia S., Kozak M., Szcześniak E., Domka L., Jurga S.

Studies of water penetration into LDPE-calcium lactate composite Penetration of water into low-density polyethylene-calcium lactate composite is studied with NMR techniques. The presence of filler speeds up the water uptake by the polymer matrix and facilitates polyethylene degradation. Spatial distribution of absorbed water molecules within the composite visualised with MRI corroborates differences in dynamical behaviour of the absorbed water molecules revealed by T-2 measurements.
(C) 2003 Elsevier Inc. All rights reserved.

Solid State Nuclear Magnetic Resonance, 25(1-3), 173-176 (2004)

DOI: 10.1016/j.ssnmr.2003.03.027   (Pobrane:  2020-10-21)


46.

Fojud Z., Szcześniak E., Jurga S., Stapf S., Kimmich R.

Molecular dynamics of n-dodecylammonium chloride in aqueous solutions investigated by 2H NMR and 1H NMR relaxometry Molecular dynamics in n-dodecylammonium chloride/water solutions for concentrations of 34 and 45wt% was studied by 2 H NMR and by H-1 NMR dispersion of spin-lattice relaxation in the 2 kHz-90 MHz frequency range. The system exhibits a number of lyotropic liquid crystalline phases, which differ in symmetry and involve motions characterized by a wide frequency scale. The analysis of H-2 NMR lineshapes of selectively deuterated DDACl molecules gave us an evidence for local trans-gauche conformational changes in the chains, whereas the dispersion of spin-lattice relaxation times T, explored by fast field cycling method revealed fast local motions, translational diffusion and collective molecular dynamics of the chains. In particular, we have found that the order director fluctuation mechanism in smectic and nematic phases dominates spin-lattice relaxation below I MHz and that local motions and translational diffusion are responsible for the spin-lattice relaxation in the higher Larmor frequency range.
(C) 2003 Elsevier Inc. All rights reserved.

Solid State Nuclear Magnetic Resonance, 25(1-3), 200-206 (2004)

DOI: 10.1016/j.ssnmr.2003.07.002   (Pobrane:  2020-10-21)


45.

Nozirov F., Szcześniak E., Fojud Z., Dobrzyński P., Klinowski J., Jurga S.

1H and 13C NMR studies of molecular dynamics in the biocopolymer of glycolide and epsilon-caprolactone Copolymers of glycolide and F-caprolactone were studied using differential scanning calorimetry and solid-state NMR. The variation of the T-1 relaxation time with temperature reflects local disorder and can be quantified in terms of the distribution of correlation times predicted by the Davidson-Cole model. T-1 relaxation is dominated by trans gauche lisomerisation, with an activation energy of 34-35 kJ mol(-1).
(C) 2002 Elsevier Science (USA).

Solid State Nuclear Magnetic Resonance, 22(1), 19-28 (2002)

DOI: 10.1006/snmr.2002.0056   (Pobrane:  2020-10-21)


44.

Szcześniak E.

Autorstwo lub wspólautorstwo książki, podręcznika akademickiego, monografii, zeszytów ćwiczeń i innych materiałów dydaktycznych, a także redakcja edytorska, słowo wstępne,
w wydawnictwach naukowych ISSN lub ISBN,
oraz w wydawnictwach popularno - naukowych.

Postępy Fizyki, 53(1), 54-55 (2002)

WWW: http://www.ptf.net.pl/pl/aktualnosci/informacje-biezace/archiwum-postepow-fizyki/
ISSN: 0032-5430   (Pobrane:  2021-01-11)


43.

Kuśmia S., Szcześniak E., Jurga S.

Magnetic resonance imaging of solid polymer composite In this paper the use of magic echo phase encoding (MEPSI) technique to obtain magnetic resonance image of the solid polymer composite is reported. The 2D version of MEPSI without slice selection has been adapted. The experiment shows that one can obtain an image of a solid sample whose transverse relaxation time is of the order of dozen of microseconds.

Molecular Physics Reports, 33, 184-187 (2001)

WWW: http://www.ifmpan.poznan.pl/mol/
ISSN: 1505-1250   (Pobrane:  2021-01-07)


42.

Nozirov F., Fojud Z., Szcześniak E., Jurga S.

Molecular dynamics in poly[(R)-3-hydroxybutyric acid] biopolymer as studied by NMR Nuclear magnetic resonance line shapes and spin-lattice relaxation rimes T-1 of H-1 and H-2 nuclei of poly[(R)-3-hydroxybutyric acid] have been measured in the temperature range 100-413 K. The results provide information on the local dynamics of the compound. Activation parameters of the revealed motion are determined.

Applied Magnetic Resonance, 18(1), 37-45 (2000)

DOI: 10.1007/BF03162097


41.

Fojud Z., Szcześniak E., Jurga K., Jurga S.

Molecular dynamics of n-dodecylammonium chloride studied by nuclear magnetic resonance The relation between molecular dynamics and phase properties of the bilayered compound C12H25NH3Cl is studied by differential scanning calorimetry, proton second moment, and spin-lattice relaxation Limes. In the low-temperature Phase I of the compound methyl and ammonium groups execute a classical threefold reorientation, while the alkylammonium chains are rigid on the nuclear magnetic resonance time scale. In the intermediate-temperature phase delta a trans-gauche isomerization of the alkyl chains is observed. In the high-temperature phase alpha the reorientation of the whole chains about their long axes, which are parallel to the normal to the ionic layer is evidenced. In the meta-stable epsilon phase the dynamics involves classical rotation of methyl and ammonium groups and CH2 groups motion of the trans-gauche isomerization type.

Applied Magnetic Resonance, 19(3-4), 413-420 (2000)

DOI: 10.1007/BF03162384


40.

Andrew E.R., Głowinkowski S., Radomski J., Szcześniak E.

Molecular dynamics in solid pregnenolone studied by 1H spin-lattice relaxation Spin-lattice relaxation times T-1 in solid pregnenolone have been studied over a wide range of temperatures, from 77 up to 417 K. The dynamic processes arising from C-3 motion of the three methyl substituents are separated, and their activation parameters are determined.
(C) 2000 Elsevier Science B.V. All rights reserved.

Solid State Nuclear Magnetic Resonance, 15(4), 227-230 (2000)

DOI: 10.1016/S0926-2040(99)00062-4   (Pobrane:  2020-10-21)


39.

Fojud Z., Boeffel C., Szcześniak E., Jurga S.

2H and 13C CPMAS NMR study of chain dynamics in n-dodecylammonium chloride The H-2 NMR spectra of the selectively deuterated polycrystalline n-dodecylammonium chloride as well as C-13 CPMAS spectra of this compound are studied over a wide range of temperature. The results reveal a variety of phase transitions occurring in this model bilayer system and make it possible to relate them to the local molecular dynamics of the alkyl chains.
(C) 2000 Elsevier Science B.V. All rights reserved.

Journal of Molecular Structure, 555, 107-117 (2000)

DOI: 10.1016/S0022-2860(00)00592-5   (Pobrane:  2020-10-21)


38.

Kuśmia S., Szcześniak E., Jurga S.

Visualisation of fluid migration into porous poly(vinylalkohol) using MRI techniques Information on migration of liquids into porous media and on mobility of the absorbed fluids is of great relevance for the theory and for many branches of the materials science. In this paper we use magnetic resonance microimaging to visualise migration of water and chloroform into porous poly(vinylalkohol) (PVA). The images taken using gradient echo fast imaging (GEFI) and constant time imaging (CTI) methods show differences, which are assumed to reflect the restriction of mobility of water molecules due to formation of hydrogen bonds with hydrophilic PVA.

Molecular Physics Reports, 28, 106-108 (2000)

WWW: http://www.ifmpan.poznan.pl/mol/
ISSN: 1505-1250   (Pobrane:  2021-01-07)


37.

Andrew E.R., Głowinkowski S., Radomski J., Szyczewski A., Szcześniak E.

Nuclear magnetic relaxation and molecular dynamics in polycrystalline estrogens: estrone and estriol Spin-lattice relaxation times T1 and T1ρ in polycrystalline estrone and estriol are measured as a function of temperature. It is found that T1 relaxation in both compounds is dominated by C-3 reorientation of the single C18 methyl group. The behaviour of T1ρ at high temperatures reveal the existence of another motion, which may involve conformational changes of the rings system.

Molecular Physics Reports, 29, 110-113 (2000)

WWW: http://www.ifmpan.poznan.pl/mol/
ISSN: 1505-1250   (Pobrane:  2021-01-07)


36.

Andrew E.R., Kempka M., Radomski J.M., Szcześniak E.

Molecular dynamics in solid anhydrous beta-estradiol studied by 1H NMR Proton second moment and spin-lattice relaxation times T-1 and T-1p in solid anhydrous beta-estradiol are measured as a function of temperature. The results show that the C-3 reorientation of the single methyl group provides the mechanism dominating relaxation at low temperatures and reveal the existence of a conformational motion of the carbon skeleton dominating relaxation at high temperatures. The activation energies of the respective motions are found to be 9.3 and 37.3 kT/mol.
(C) 1999 Elsevier Science B.V. All rights reserved.

Solid State Nuclear Magnetic Resonance, 14(2), 91-94 (1999)

DOI: 10.1016/S0926-2040(99)00009-0   (Pobrane:  2020-10-21)


35.

Suchański W., Szcześniak E., Jurga S.

Nuclear magnetic relaxation study of carbon-13 in di-pentyl phthalate Spin-lattice relaxation times T-1 and nuclear Overhauser enhancement factors of chemically non-equivalent carbons in di-pentyl phthalate (DPP), a simple glass-forming liquid, are measured as functions of temperature. The analysis shows that the correlation function describing the overall molecular dynamics in DPP can be well described in terms of an asymmetric distribution of correlation times predicted by the Davidson-Cole model. The distribution parameters beta of the successive chain carbons are derived and analysed in terms of internal motions occurring in DPP.

Journal of Physics-Condensed Matter, 11(19), 3907-3914 (1999)

DOI: 10.1088/0953-8984/11/19/310


34.

Suchański W., Szcześniak E., Jurga S.

13C NMR relaxation in supercooled di-methyl phthalate Spin-lattice relaxation times (T-1) and nuclear Overhauser enhancement factors (NOE) for the individual ring carbons in di-methyl phthalate (DMF) were measured over a wide range of temperatures. The results show that the reorientational correlation function corresponding to the global dynamics in supercooled liquid can be well described by a Davidson-Cole distribution. The viscosity dependence of the reorientational correlation time tau derived is analysed to investigate the adequacy of the modified Debye equation to description of the microscopic behaviour of supercooled systems.

Journal of Physics-Condensed Matter, 10(28), 6243-6249 (1998)

DOI: 10.1088/0953-8984/10/28/006


33.

Andrew E.R., Kempka M., Sagnowski S., Szcześniak E.

Autorstwo lub wspólautorstwo książki, podręcznika akademickiego, monografii, zeszytów ćwiczeń i innych materiałów dydaktycznych, a także redakcja edytorska, słowo wstępne,
w wydawnictwach naukowych ISSN lub ISBN,
oraz w wydawnictwach popularno - naukowych.

Novel gradient coils for magnetic resonance microscopy This paper describes three magnetic field gradient coils of considerable simplicity, two for transverse gradient and one for longitudinal gradients. The coaxial arc gradient coil has a simple unit construction of symmetric form. It features a large volume of uniform transverse field gradient, high efficiency and low inductance rapid switching. A prototype coil was first constructed and a smaller coil set was [hen constructed for NMR microscopy, with excellent results. The system may be used for all sizes from microimaging to whole-body MRI. The second transverse gradient coil uses full circle current paths rather than current arcs. It has an even simpler form of construction and has closely similar properties to the coaxial arc transverse gradient coil. A prototype coil set was first made and two smaller coil sets have been made for NMR. microscopy. The longitudinal gradient coil is based on an analysis of the multipole expansion of the external field of a gradient coil system. It is first shown that a Maxwell pair has no hexadecapole moment. The field outside such a pair therefore falls as r-4 from the quad-rupole moment and as r-8 from the 64-pole moment. Using a nested pair of Maxwell pairs the quadrupole term is canceled leaving only the rapid attenuation of the r-8 term, thus providing a simple screened Longitudinal gradient coil.

Spatial resolved magnetic resonance, Eds. Blumler P., Blumich B., Botto R., Fukushima E., WILEY-VCH, Weinheim, New York, Chichester, Brisbane, Singapore, Toronto, , 683-693 (1998)

WWW: http://onlinelibrary.wiley.com/book/10.1002/9783527611843
ISBN: 9783527296378   (Pobrane:  2021-01-14)


32.

Szcześniak E., Głowinkowski S., Suchański W., Jurga S.

Dynamics of glass-forming di-n-butyl phthalate as studied by NMR Spin-lattice relaxation times T-1 and nuclear Overhauser effect (NOE) enhancement factors for the individual ring carbons in di-n-butyl phthalate (DBF) show that the reorientational correlation function corresponding to the global dynamics in supercooled liquid can be described by a Davidson-Cole distribution. Measurements of proton spin-lattice relaxation times T-1 and T-1p, as well as H-1 NMR spectra at temperatures below the glass transition temperature, Tg, reveal that the same distribution holds also for description of local dynamics in glassy DBF. The activation parameters of the motions detected are derived.
(C) 1997 Elsevier Science B.V.

Solid State Nuclear Magnetic Resonance, 8(2), 73-79 (1997)

DOI: 10.1016/S0926-2040(96)01292-1   (Pobrane:  2020-10-21)


31.

Głowinkowski S., Jurga S., Suchański W., Szcześniak E.

Local and global dynamics in the glass-forming di-isobutyl phthalate as studied by 1H NMR Spin-lattice relaxation times T-1 and T1ρ as well as H-1 NMR spectra have been employed to study the dynamics of the glass-forming di-isobutyl phthalate in the temperature range extending from 100 K, through the glass transition temperature Tg, up to 340 K. Below Tg NMR relaxation is governed by local dynamics and may be attributed to rotation of methyl groups at low temperatures and to motion of isobutyl groups in the intermediate temperature interval. Above Tg the main relaxation mechanism is provided by overall molecular motion. The observed relaxation behavior is explained by motional models assuming asymmetrical distributions of correlation times. The motional parameters obtained from Davidson-Cole distribution, which yields the best fit of the data at all temperatures are given.
(C) 1997 Elsevier Science B.V.

Solid State Nuclear Magnetic Resonance, 7(4), 313-317 (1997)

DOI: 10.1016/S0926-2040(96)01266-0   (Pobrane:  2020-10-23)


30.

Andrew E.R., Kempka M., Szcześniak E.

IV International Conference on Magnetic Resonance Microscopy and Macroscopy, Albuquerque (New Mexico / USA), , 52 (1997)


29.

Buszko M.L., Kempka M.F., Szcześniak E., Wang D.C., Andrew E.R.

Optimization of transverse gradient coils with coaxial return paths by simulated annealing Coils with coaxial return paths are used to generate transverse magnetic field gradients. This paper describes optimization of such coils by the method of simulated annealing, a method known to be able to find the global minimum of a function. The adaptive simulated annealing (ASA) program has been analyzed and applied to optimization of a family of coils with 8-16 building blocks, each carrying equal current. Positions of the blocks along the longitudinal axis of the coils were optimized. A new subclass of coils is proposed; the diameter of return paths of this subclass of coils is not fixed but may be varied, The new coils provide greater gradient uniformity than those for which only positions of the blocks are optimized, All optimized coils should find applications in high-precision and high-resolution imaging and spectroscopic experiments.
(C) 1996 Academic Press, Inc.

Journal of Magnetic Resonance Series B, 112(3), 207-213 (1996)

DOI: 10.1006/jmrb.1996.0133   (Pobrane:  2020-10-21)


28.

Andrew E.R., Inglis B.A., Kempka M., Mareci T.H., Szcześniak E.

Magnetic field gradient system for nuclear magnetic resonance microimaging In this study we present an orthogonal magnetic field gradient system for nuclear magnetic resonance (NMR) microimaging applications. The construction details are given for a prototype assembly for proton microscopy inside a 50-mm vertical bore magnet, which is designed to fit into a commercial 300-MHz NMR probe. This system has been used to acquire images of the human spinal cord in vitro. Its performance has been evaluated and compared to that predicted by computer simulation.

Magnetic Resonance Materials in Physics Biology and Medicine - MAGMA, 4(24), 85-91 (1996)

DOI: 10.1007/BF01772515   (Pobrane:  2021-01-07)


27.

Głowinkowski S., Jurga S., Suchański W., Szcześniak E.

Dynamics of t-butyl groups in a series of related molecular solids The dynamics of the lowest temperature phase of a series of closely related t-butyl compounds (CH3)CXH, whre X=O, S, Se, has been studied using 1H NMR. The obtained data allowed the separation of the dynamics arising from methyl group and from t-butyl group. The activation parameters of the motions are given. It is shown that the t-butyl group is more mobile than constituent methyl groups and that coupling between these two motions is associated with the observed order-disorder phase transition.

Molecular Physics Reports, 14, 83-87 (1996)

WWW: http://www.ifmpan.poznan.pl/mol/
ISSN: 1505-1250   (Pobrane:  2021-01-07)


26.

Głowinkowski S., Suchański W., Szcześniak E.

Molecular dynamics in glassy di-isobutyl phalate as studied by 1H NMR This volume contains the proceedings of the International Workshop on "Non-Equilibrium Phenomena in Supercooled Fluids, Glasses and Amorphous Materials", held in Pisa in the early fall of 1995 as a joint initiative of the Unviersity of Pisa and of the Scuola Normale Superiore

World Scientific Series in Contemporary Chemical Physics - Non Equilibrium Phenomena in Supercooled Fluids, Glasses and Amorphous Materials, 12, Eds. Giordana M. et al., World Scientific, Singapore (1996)

WWW: http://www.worldcat.org/title/non-equilibrium-phenomena-in-supercooled-fluids-glasses-and-amorphous-materials-proceedings-of-the-workshop-a-euroconference-pisa-italy-25-29-september-1995
ISBN: 9789814530774   (Pobrane:  2021-01-14)


25.

Andrew E.R., Szcześniak E.

Low inductance transverse gradient system of restricted length A new transverse gradient coil assembly of restricted length is presented. The coil is symmetric, has the advantage of simplicity, generates a remarkably large volume of uniform transverse gradient field, features very low inductance, and can therefore be suitable for applications requiring fast switched gradients. A prototype coil has been constructed to check computer simulations and to compare measured parameters of the system with those expected. Coils of this type may be used for MRI of the human head, and of animals, and for NMR microimaging.

Magnetic Resonance Imaging, 13(4), 607-613 (1995)

DOI: 10.1016/0730-725X(95)00002-X


24.

Andrew E.R., Szcześniak E.

A historical account of NMR in the solid state This article attempts to chronicle major milestones in the application of NMR in the solid state over the first 50 years since the discovery of NMR in 1945. After recording the earliest experiments with solids, we discuss in approximate chronological order the following topics: structure of solids, dynamics of solids including molecular reorientation, selfdiffusion and conformational motion, quadrupole effects, NQR, metals, negative temperatures, rotating frame temperatures, magnets and experimental methods, Fourier transform methods, magic angle spinning, multiple pulse NMR, CP/MAS, CRAMPS, double resonance, Overhauser effect, magnetic materials, ordered nuclear spin systems, phase transitions in solids, surfaces of solids, zero field NMR, 2D NMR, multiple quantum and overtone NMR in solids, NMR in high temperature superconductors, NMR in fullerenes, NMR imaging of solids, NMR force spectroscopy.

Progress in Nuclear Magnetic Resonance Spectroscopy, 28, 11-36 (1995)

DOI: 10.1016/0079-6565(95)01018-1


23.

Buszko M.L., Kempka M., Szcześniak E., Wang D.C., Andrew E.R.

12th Conference of the International Society of Magnetic Resonance, ISMAR, T28, Sydney (Australia), , 95 (1995)


22.

Buszko M.L., Kempka M., Szcześniak E., Wang D.C., Andrew E.R.

36th Experimental Nuclear Magnetic Resonance Conference, Boston (USA), , 360 (1995)


21.

Szcześniak E., Głowinkowski S., Jurga S.

Proccedings of 15th Conference on Radio and Microwave Spectroscopy, Poznań (Poland), , 89 (1993)


20.

Głowinkowski S., Jurga S., Szcześniak E.

Interrelation between molecular motions and structure in solid trimethylamine-boron-trichloride as studied by NMR The temperature dependences of proton second-moment and spin-lattice relaxation times (T1 and T1Q) have been measured in solid (CH3)3NBCl3. The nature of reorientation processes occurring in the complex has been established and the activation parameters determined. The motions are discussed in relation to the molecular structure of the complex.

Zeitschrift fur Naturforschung Section A-A Journal of Physical Sciences, 47(11), 1157-1160 (1992)

DOI: 10.1515/zna-1992-1113   (Pobrane:  2021-01-10)


19.

Andrew E.R., Szcześniak E.

Magnetic shielding of magnetic resonance systems Basic theoretical concepts of static magnetic shielding are summarized. Expressions describing the magnetic field produced by a solenoidal coil confined coaxially inside a long thin ferromagnetic cylinder of constant permeability are derived. Conditions for the optimum arrangement of a magnetic screen for whole-body NMR systems are discussed.
(C) 1989 Academic Press, Inc.

Magnetic Resonance in Medicine, 10(3), 373-387 (1989)

DOI: 10.1002/mrm.1910100309


18.

Reynhardt E.C., Froneman S., Andrew E.R., Szcześniak E.

An NMR study of 1H, 31P, and 23Na relaxation and molecular dynamics in the polycrystalline sodium salt of adenosine monophosphate Proton spin-lattice relaxation times in the laboratory frame, T1 (H), have been measured as a function of frequency and temperature (295 K > T > 90 K). The spin-lattice relaxation times in the rotating frame have been measured at two different rotating fields, while the proton second moment has been obtained from the lineshapes. In addition, T1(31P) and T1 (23Na) have been measured as functions of temperature at 81 and 50 MHz, respectively. The results demonstrate clearly that the water content of the compound influences the results to a large extent. It seems that water molecules at some of the lattice sites can be removed from the structure by evacuation, while others are more tightly bound to the AMP molecule. The more loosely bound water molecules are very mobile and dominate the relaxation results in the high-temperature region via the spin-rotation and dipolar mechanisms. The more tightly bound water molecules rotate about their twofold axes and this motion, characterized by a distribution of correlation times, influences the T1 (H) results at lower temperatures. The 23Na spin-lattice relaxation rate is dominated by the quadrupolar interactions, which also provide a dominating relaxation mechanism for the proton spins in the rotating frame. T1 (P) is strongly dependent on the water content of the sample.

Journal of Magnetic Resonance (1969), 84(1), 110-120 (1989)

DOI: 10.1016/0022-2364(89)90009-7


17.

Andrew E.R., Jurga K., Szcześniak E.

Proccedings X ISMAR Meeting, Morzine (France), , (1989)


16.

Andrew E.R., Jurga K., Szcześniak E.

Molecular motions and polymorphic properties of solid 2-methyl-2-propaneselenol as studied by NMR The spin-lattice relaxation times (T1, T1ρ and T1D) as well as the second moment of the proton spectrum for (CH3)3CSeH have been studied between 77 K and room temperature. The data reveal four transition temperatures 95, 117, 144 and 168 K, the last one the melting point, and provide some basic information on the motional properties of the respective four solid state phases. In the lowest temperature phase IV there is uniaxial C′3 motion and methyl groups C3 rotation. The activation energy for the C′ 3 motion dominating T 1 relaxation is found to be 5·5 kJ mol-1. The spin-lattice relaxation in phase III reflects a complex motional behaviour of the methyl groups, consistent with a distribution of correlation times. The transition to phase II involves a new motion, possibly restricted molecular reorientation, of frequency 7-28 MHz. There is considerably molecular freedom in the highest temperature phase I, enabling molecular tumbling as well as self-diffusion of molecules to occur, a common feature for plastic crystals.

Molecular Physics, 65(6), 1421-1430 (1988)

DOI: 10.1080/00268978800101891


15.

Andrew E.R., Szcześniak E.

Proccedings XXVI Congress AMPERE, Poznań (Poland), , (1988)


14.

Szcześniak E.

Autorstwo lub wspólautorstwo książki, podręcznika akademickiego, monografii, zeszytów ćwiczeń i innych materiałów dydaktycznych, a także redakcja edytorska, słowo wstępne,
w wydawnictwach naukowych ISSN lub ISBN,
oraz w wydawnictwach popularno - naukowych.

Wiadomości Chemiczne, 42, 65 (1988)

WWW: http://www.ptchem.pl/portal-wiedzy/czasopisma
ISSN: 0043-5104   (Pobrane:  2021-01-14)


13.

Andrew E.R., Szcześniak E.

SMRM 6th Annual Meeting, New York (USA), , (1987)


12.

Szcześniak E.

Molecular dynamics and phase transitions in solid 2-methyl-2-propanethiol studied by 1H NMR relaxation Spin-lattice relaxation times T 1 and T 1ρ for protons in solid 2-methyl-2-propanethiol are presented. The relaxation measurements corroborate the existence of three solid-solid transitions and give some insight into their nature. The motions occurring in the respective phase modifications are discussed and their activation parameters derived.

Molecular Physics, 58(3), 551-560 (1986)

DOI: 10.1080/00268978600101361


11.

Szcześniak E.

NMR study of molecular dynamics and phase transitions in solid 2-methyl-2-propanol Proton second moment and spin-lattice relaxation times (T 1 and T 1ρ) have been studied in solid 2-methyl-2-propanol in the temperature interval 77 K to the melting point. The data at low temperatures are satisfactorily explained in terms of simultaneous methyl and t-butyl motions. The activation energies of these motions are of 22·3 and 13·2 kJ mol-1, respectively. At high temperatures the relaxation, particularly T 1ρ, is influenced by translational diffusion. The energy barrier to this process is estimated roughly to be of about 137 kJ mol-1. The results confirm the existence of the phase transition at around 287 K and indicate that it may originate from the coupling between internal motions.

Molecular Physics, 59(4), 679-688 (1986)

DOI: 10.1080/00268978600102331


10.

Szcześniak E.

Proccedings XXIII Congress AMPERE, Roma (Italy), , (1986)

   (Pobrane:  2020-10-21)


9.

Szcześniak E.

Autorstwo lub wspólautorstwo książki, podręcznika akademickiego, monografii, zeszytów ćwiczeń i innych materiałów dydaktycznych, a także redakcja edytorska, słowo wstępne,
w wydawnictwach naukowych ISSN lub ISBN,
oraz w wydawnictwach popularno - naukowych.

Postępy zastosowań technik rezonansowych w chemii, red. L.Sobczyk, PWN, Warszawa, , (1984)


ISBN: 83-01-04687-2   (Pobrane:  2021-01-14)


8.

Pająk Z., Szcześniak E.

NMR study of solid perfluorocyclobutane Spin-lattice relaxation times and linewidth measurements for fluorine nuclei in solid perfluorocyclobutane are presented. The results are discussed in terms of D 2d molecular species performing fast internal motion. The relaxation measurements corroborate the existance of four solid-solid phase transitions and give some insight into their nature. The activation energies for molecular reorientation and self-diffusion processes are found to be 28·0 and 32·2 kJ mol-1, respectively.

Molecular Physics, 48(6), 1221-1228 (1983)

DOI: 10.1080/00268978300100871


7.

Pająk Z., Szcześniak E.

Molecular microdynamics of liquid propionic acid Quantitative analysis of the temperature dependence of selectively measured spin-lattice relaxation times of the hydroxyl, methylene and methyl protons of propionic acid yields the hindering potentials characterizing evidenced overall and internal reorientational motions of separate fragments within the dimeric molecule: E0 = 15,98 kJ mol−1, E1 = 15,77 kJ mol−1 and E2 = 8,87 kJ mol−1.
Eine quantitative Analyse der Temperaturabhängigkeit von selektiv gemessenen Spin-Gitter-Relaxationszeiten der Hydroxyl-, Methylen-und Methylprotonen der Propionsäure liefert die Potentialbarrieren, die die Reorientierungsrotationen des gesamten Moleküls und die einzelner Molekülbausteine innerhalb des dimeren Moleküls bestimmen. E0 = 15,98 kJ/mol−1, E1 = 15,77 kJ/mol−1 und E2 = 8,87 kJ/mol−1.

Berichte der Bunsengesellschaft fur physikalische Chemie, 83(10), 980-982 (1979)

DOI: 10.1002/bbpc.19790831005


6.

Szcześniak E.

Autorstwo lub wspólautorstwo książki, podręcznika akademickiego, monografii, zeszytów ćwiczeń i innych materiałów dydaktycznych, a także redakcja edytorska, słowo wstępne,
w wydawnictwach naukowych ISSN lub ISBN,
oraz w wydawnictwach popularno - naukowych.

Fizyka Dielektryków i Radiospektroskopia, X, 267 (1978)

WWW: Poznańskie Towarzystwo Przyjaciół Nauk. Wydział Matematyczno-Przyrodniczy, PWN, Warszawa
ISSN: 0137-8996   (Pobrane:  2021-01-14)


5.

Pająk Z., Szcześniak E.

Structure and microdynamic behaviour of liquid formic acid The cyclic dimer structure of formic acid is proved to be stable from quantitative analysis of the temperature dependence of selectively measured spin-lattice relaxation times of the hydroxyl and formyl protons. The rotational and translational motion of the predominant molecular species is well described by the microviscosity and Stokes-Einstein models.

Chemical Physics Letters, 49(2), 269-272 (1977)

DOI: 10.1016/0009-2614(77)80584-8


4.

Pająk Z., Szcześniak E.

Microdynamic behaviour of liquid carboxylic acids Selective measurements of proton spin-lattice relaxation times of chemically shifted protons in simple carboxylic acids at various temperatures and concentrations in CCl4 yield effective correlation times for molecular fragments independently reorienting about consecutive C-C bonds. For methyl protons of acetic acid, strong spin-internal rotation coupling is indicated.

Chemical Physics Letters, 40(3), 487-491 (1976)

DOI: 10.1016/0009-2614(76)85125-1


3.

Pająk Z., Angerer J., Szcześniak E., Jurga J.

Proccedings XVI AMPERE Congres, Bucharest (Romania), , (1971)


2.

Pająk Z., Szcześniak E., Angerer J., Jurga K.

Acta Physica Polonica A, A38, 767 (1970)


1.

Pająk Z., Angerer J., Szcześniak E., Wróż W., Mielniczuk L.

Acta Physica Polonica A, A38, 91 (1970)


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