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1

Application of Mössbauer Spectroscopy in Study of Selected Biochemical Processes

100%

Burda K., Stanek J.

Acta Physica Polonica A

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2003

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vol. 103

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issue 5

499-509

EN

The ^{57}Fe, ^{119}Sn, ^{129}I, and ^{151}Eu Mössbauer spectroscopy, scanning force microscopy, and optical fluorescence method were applied to study biological systems starting from porphyrins, through cytochromes and cell membranes until such a complex system as photosystem II. In Fe-porphyrin aggregates iron atoms are able to trap an electron exhibiting the mixed valence Fe^{3+}-Fe^{2+} relaxation process. In ironcytochrome c the presence of two different Fe^{3+} states are indicated, while in tincytochrome Sn appears in Sn^{4+} and Sn^{2+} states. From the temperature dependence of the mean square displacement of the resonance nuclei and from the diffusional broadening of the Mössbauer line it was possible to separate the vibrational, fast collective and slow collective motions in tinporphyrin and in iron- and tin-cytochrome c. The electronic state of iodine in oleic acid, the main constituent of cellular membranes, was determined. The molecular mechanism of triphenyltin interaction with membrane of red blood cells has been suggested and the model of haemolysis has been proposed. In photosystem II, Eu ions replacing calcium showed Eu^{3+} to Eu^{2+} transition after illumination with light, which points out the possible role of Ca^{2+} ions in electron transfer in the process of photosynthetic water splitting process.

2

Mobility of Hematite Submicron Particles in Water Solutions of Sugar

100%

Fornal P., Stanek J.

Acta Physica Polonica A

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2008

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vol. 114

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issue 6

1667-1673

EN

The mobility of the 100 nm Fe_2O_3 particles in dense water solutions of sugar (sucrose) was determined from the analysis of the resonance absorption line shape of the Mössbauer spectra recorded in the -5°C to 40°C temperature range for different sugar concentrations. The discrepancy between the experimental data and the prediction of the classical theory of Brownian movement are interpreted in the term of the short observation time and the interaction between the solid particles in fluids, which extends in water up to 300 nm. The sedimentation process in the studied colloids was observed.

3

Brownian Movement of Inorganic Nanoparticles in Sediments

100%

Fornal P., Stanek J.

Acta Physica Polonica A

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2011

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vol. 119

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issue 1

12-14

EN

The 100 nm particles of Fe_{2}O_{3} and metallic Fe sedimented jointly with Al_{2}O_{3} powder from their suspension in oleic acid exhibit distinguished mobility which depends on the concentration of aluminum oxide. This observation is interpreted as the result of the interparticle Fe-Fe magnetic interactions which lead to the formation of the rigid network of magnetic metallic iron nanoparticles.

4

Microstructure and Dynamics of Magnetic Iron Nanoparticles Aggregates in Protein Gels

81%

Konik K., Fornal P., Okła D., Stanek J.

Acta Physica Polonica A

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2012

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vol. 121

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issue 2

457-463

EN

The 60 nm metallic iron nanoparticles and its aggregates in gelatine gel were studied by means of optical microscopy, X-ray microtomography, atomic force scanning microscopy and the Mössbauer spectroscopy. The isolated nanoparticles in gel exhibit fast bounded diffusion described by Brownian movement. In the external magnetic field these magnetic particles form spectacular linear aggregates whose local dynamical and magnetic properties were determined from the Mössbauer spectra.

5

Spectroscopic Study of the Dimerization Process οf Iron Protoporphyrin IX

81%

Dziedzic-Kocurek K., Byrne H., Świderski A., Stanek J.

Acta Physica Polonica A

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2009

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vol. 115

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issue 2

552-555

EN

The commercial protoporphyrin IX, iron-ferriprotoporphyrin IX-chloride and synthesized iron porphyrin μ-oxo-dimers were examined by UV/vis absorption and fluorescence, Fourier transformed infrared spectroscopy, resonance Raman, X-ray absorption, Mössbauer spectroscopy and SQUID. The evidence of Fe-O-Fe antiferromagnetic coupling concluded from SQUID and Mössbauer in the case of samples containing dimerized forms confirmed the presence of the oxo-bridges. In this paper the results of UV/vis, fluorescence, Fourier transform infrared FTIR and Raman spectroscopies are reported and discussed. The study is based on the comparison of the free-base protoporphyrin IX, Fe-PPIX-Cl and the synthesized dimerized specimen. The vibrational modes in two energy regions i.e. 330-650 cm^{-1} and 750-900 cm^{-1}, reportedly characteristic of the existence of Fe-O-Fe bridges, are discussed. A significant photoluminescence emission, strongly Stokes shifted from the Soret band, absent in the protoporphyrin IX and the iron-ferriprotoporphyrin IX-chloride, is observed. The strong Stokes shift and the mismatch of the excitation spectrum to the Soret band suggest that is does not have origin in the de-excitation of the porphyrin moiety and that it could have origin in an Fe-O-Fe charge transfer state.

6

Lineshape Measurements of Rotational Line in Millimeter-Wave Region by Second Harmonic Detection

81%

Stanek J., Gierszal S., Galica J.

Acta Physica Polonica A

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1993

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vol. 84

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issue 6

1027-1034

EN

Lineshape measurements of the J = 6 ← 5 OCS rotational transition were performed using a source-modulation microwave spectrometer. This is a very useful experimental technique but it introduces distortions to the line profile, therefore several authors have theoretically analyzed this problem with the aim of extracting the undistorted parameters of the spectra. The objective of this paper is to verify one of these theories which gives the relationship between harmonic signals and lineshape over wide range of modulation depth. Detailed comparison between the calculated and experimental harmonic signals shows very good agreement, and thus enables us to determine the unmodified line width and finally the pressure broadening factor of the rotational transition J = 6 ← 5 of OCS molecule to be equal to 6.59 ± 0.25 MHz/Tr.

7

Local States of Tellurium in Isolated Helical Chains

81%

Stanek J., Fornal P., Hafner S., Pfitzner A.

Acta Physica Polonica A

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2001

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vol. 100

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issue 5

807-815

EN

The local electronic state of Te in the helical chains of CuXY_{2(1-x)}Te_{2x} (X = Cl, Br; Y = Se, S) were studied using the Mössbauer spectroscopy of ^{125}Te at 10 K and 70 K. The isolated chains of Te in these compounds are less rigid than those in elemental Te. The determined data of quadrupole splittingΔ and Debye temperatureΘ_D are indicative of strong local ordering of Te in one of the two non-equivalent crystallographic positions. It was not possible to resolve crystallographic positions by the Mössbauer spectroscopy.

8

X-Ray Absorption Near Edge Structure and Mössbauer Spectroscopy in Study of Iron Valence States in Tissues

81%

Dziedzic-Kocurek K., Banaś A., Kwiatek W., Stanek J.

Acta Physica Polonica A

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2006

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vol. 109

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issue 3

341-345

EN

X-ray absorption near edge structure Fe K-edge spectra and ^{57}Fe Mössbauer spectra of selected standard compounds were recorded at room temperature. Valence and spin states of Fe in these samples known from Mössbauer spectroscopy were correlated with the shapes of X-ray absorption near edge structure spectra in search of possible application of X-ray absorption near edge structure spectroscopy as analytical tool determining local electronic states of iron in tissues. As an example, the X-ray absorption near edge structure spectra of healthy and cancerous tissues of prostate are shown, suggesting Fe^{3+} in cancerous tissues.

9

Mössbauer, XRD, and SEM Study of FeAl-Based Powder Alloys with Nanoinclusions

61%

Zaleski A., Fedotova J., Ilyuschenko A., Talako T., Belyaev A., Letsko A., Stanek J.

Acta Physica Polonica A

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2006

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vol. 109

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issue 3

441-444

EN

Peculiarities of phase composition and morphology in nanostructured (Fe_{70}Al_{30})_{1-x}(Al_2O_3)_x (x=64-80 wt.%) powder alloys prepared by self-propagated high temperature synthesis have been studied by ^{57}Fe transmission Mössbauer spectroscopy, scanning electron microscopy, and X-ray diffraction. It has been established that phase composition of alloys has not been affected by Al_2O_3 contribution. Contrary, atomic arrangement in B2 FeAl phase depends on the volume fraction of Al_2O_3 resulting in the migration of Al atoms from B2 FeAl lattice.

10

Mössbauer Studies of Cu(II) Ions Interaction with the Non-Heme Iron and Cytochrome b_{559} in a Chlamydomonas reinhardtii PSI Minus Mutant

61%

Burda K., Kruk J., Strzałka K., Stanek J., Schmid G., Kruse O.

Acta Physica Polonica A

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2006

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vol. 109

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issue 3

237-247

EN

Mössbauer spectroscopy was applied, for the first time, to study the interaction of copper ions with the non-heme iron and the heme iron of cytochrome b_{559} in photosystem II thylakoids isolated from a Chlamydomonas reinhardtii photosystem I minus mutant. We showed that copper ions oxidize the heme iron and change its low spin state into a high spin state. This is probably due to deprotonation of the histidine coordinating the heme. We also found that copper preserves the non-heme iron in a low spin ferrous state, enhancing the covalence of iron bonds as compared to the untreated sample. We suggest that a disruption of hydrogen bonds stabilizing the quinone-iron complex by Cu^{2+} is the mechanism responsible for a new arrangement of the binding site of the non-heme iron leading to its more "tense" structure. Such a diamagnetic state of the non-heme iron induced by copper results in a magnetic decoupling of iron from the primary quinone acceptor. These results indicate that Cu does not cause removal of the non-heme iron from its binding site. The observed Cu^{2+} action on the non-heme iron and cytochrome b_{559} is similar to that previously observed forα-tocopherol quinone.

11

Magnetoelastic Phase Transitions and Critical Behaviour of (Fe_{1-x}Ni_{x})_{2}P System

52%

Średniawa B., Duraj R., Pacyna A., Bombik A., Zach R., Bacmann M., Fruchart D., Nizioł S., Fornal P., Stanek J.

Acta Physica Polonica A

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2000

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vol. 97

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issue 5

921-925

EN

This report focuses on magnetoelastic properties and critical behaviour of (Fe_{1-x}Ni_{x})_{2}P system. For low Ni content (x=0.01) an isolated critical point was found. Analysis of this critical behaviour in the frame of molecular field approximation was carried out. Moreover, thermal variations of the lattice parameters, as measured by X-ray diffraction techniques, were studied. The (P,T) phase diagrams obtained for several Ni contents show the evidence that the Curie temperature decreases with pressure. The Mössbauer spectra collected for x = 0.025, 0.1, 0.2, 0.25 at different temperatures are also analysed. The existence of two nonequivalent crystallographic sites occupied by iron atoms as well as local magnetic structure is discussed.

Refine search results

Application of Mössbauer Spectroscopy in Study of Selected Biochemical Processes

Mobility of Hematite Submicron Particles in Water Solutions of Sugar

Brownian Movement of Inorganic Nanoparticles in Sediments

Microstructure and Dynamics of Magnetic Iron Nanoparticles Aggregates in Protein Gels

Spectroscopic Study of the Dimerization Process οf Iron Protoporphyrin IX

Lineshape Measurements of Rotational Line in Millimeter-Wave Region by Second Harmonic Detection

Local States of Tellurium in Isolated Helical Chains

X-Ray Absorption Near Edge Structure and Mössbauer Spectroscopy in Study of Iron Valence States in Tissues

Mössbauer, XRD, and SEM Study of FeAl-Based Powder Alloys with Nanoinclusions

Mössbauer Studies of Cu(II) Ions Interaction with the Non-Heme Iron and Cytochrome b_{559} in a Chlamydomonas reinhardtii PSI Minus Mutant

Magnetoelastic Phase Transitions and Critical Behaviour of (Fe_{1-x}Ni_{x})_{2}P System