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1

The use of SR - FTIR microspectroscopy for a preliminary biochemical study of the rat hippocampal formation tissue in case of pilocarpine induced epilepsy and neutroprotection with FK- 506

Dudała J., Janeczko K., Setkowicz Z., Eichert D., Chwiej J.

Nukleonika

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2012

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Vol. 57, No. 4

615-619

EN

The main aim of the work was the biochemical analysis of the hippocampal formation tissue in the case of epileptic rats treated with the neuroprotective agent FK-506. Three groups of animals were compared: rats with pilocarpine induced seizures treated and non-treated with tacrolimus as well as naive controls. Synchrotron radiation Fourier transform infrared (SR-FTIR) microspectroscopy was used for the biomolecular analysis of studied samples. The measurements were carried out at SISSI beamline of ELETTRA. A Bruker IFS 66v/S interferometer coupled to a Bruker Hyperion 2000 microscope was used. The tissue samples were analyzed in transmission mode with a beam defined by a small aperture and spatial resolution steps of 10 mi m which allowed us to probe the selected cross-line of the sample at cellular resolution. The obtained results enabled to compare the distributions of proteins and lipids in the three hippocampal cellular layers, i.e. in molecular, multiform and granular layers. For epileptic animals both treated and non-treated with FK-506, the tendency for increase of the ratio of the absorbance at around 1548 and 1658 cm-1 (amide II/amide I ratio) was observed, however only for the multiform layer these changes were statistically significant. Similar relation was noticed in case of the ratio of the absorbance at around 1631 and 1658 cm-1. The mentioned results may suggest conformational changes of proteins in the direction of beta-sheet secondary structure. Additionally, a statistically significant increase in the lipid massif and a decrease of the ratio of absorbance at around 2921 and 2958 cm-1 were observed for epileptic animals treated with tacrolimus comparing to the control group.

2

Rok 2009 w energetyce: przełomu nie było

Dudała J.

Energetyka Cieplna i Zawodowa

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2010

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Nr 2

14--17

PL

Dla branży energetycznej rok 2009 był całkiem dobry, mimo spowolnienia w gospodarce oraz spadku produkcji przemysłowej. To właśnie w ubiegłym roku Rada Ministrów przyjęła Politykę energetyczną Polski do 2030 roku.

3

Simultaneous measurement of Cr, Mn and Fe diffusion in chromium-manganese steels

Dudała J., Gilewicz-Wolter J., Stęgowski Z.

Nukleonika

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2005

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Vol. 50, nr 2

67-71

EN

The paper presents an application of multitracer method to diffusion measurement in Cr-Mn steels. Radioisotope tracers of chromium 51Cr, manganese 54Mn and iron 59Fe were used simultaneously in the diffusion process. Measurements of gamma-ray spectra and the proper analysis enabled evaluation of concentration distribution for each tracer. As a new tool, artificial neural networks (ANN) method was used for analysis of spectra. The proper solution of the diffusion model was applied to the experimental tracers' distribution data and diffusion coefficients were determined.

4

Wysokotemperaturowa korozja stali chromowo-manganowych w dwutlenku siarki

Żurek Z., Gilewicz-Wolter J., Hetmańczyk M., Dudała J.

Inżynieria Materiałowa

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2004

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R. XXV, nr 1

5-10

PL

Celem niniejszej pracy była próba wyjaśnienia mechanizmu korozji przemysłowych stali chromowo-manganowych w atmosferach tlenowo--siarkowych. Do badań wytypowano trzy rodzaje stali, austenityczne Cr17Mn17 i Cr13Mn18SiCa oraz stal austenityczno-ferrytyczną Cr15Mn19. Opis mechanizmu korozji oparto na wynikach badań składu i budowy morfologicznej zgorzelin (SEM-EDX, XRD, SIMS, mikroskopia optyczna), kinetyki procesu (metoda grawimetryczna) oraz transportu siarki przez zgorzelinę (metoda radioizotopowa). Stwierdzono, że wewnętrzna, drobnoziarnista warstwa zawiera siarczki Mn i Cr, warstwa pośrednia zbudowana jest głównie ze spinelu MnCr2O4 natomiast dominującym składnikiem warstwy zewnętrznej jest MnO. Badania kinetyki utleniania stali wykazały, że po początkowym okresie inkubacji lub przebiegu liniowego następuje etap opisywany prawem parabolicznym. W trakcie utleniania dochodzi do zubożenia przypowierzchniowej warstwy rdzenia w austenitotwórczy mangan, co w konsekwencji prowadzi do przemiany fazowej austenitu w ferryt, w którym dyfuzja manganu zachodzi wolniej. W związku z tym faktem oraz zważywszy, że najwolniejszym procesem cząstkowym jest dyfuzja reagujących metali w stali, obserwowano spowolnienie ostatniego etapu utleniania.

EN

The presented corrosion mechanism was based on the results of studies of composition and morphological structure of scales - Fig. 4, 5 (SEM-EDX, XRD, SIMS, optical microscope), kinetics of the process - Fig. 1 (gravimetric method) and radiotracer studies of sulphur transport through the scale - Fig. 2, 3. Three types of steels were taken into consideration, austenitic steels: Cr13Mn18SiCa and Cr17Mn17 as well as austenitic-ferritic steel: Cr15Mn19. It was found that the thin inner, fine grained layer consists sulphides of Mn and Cr, the intermediate layer is built mainly of MnCr2O4 spinel whereas MnO is the main component of the outer layer. On the base of the kinetics studies it was pointed, that linear stage of the process is followed by the parabolic stage - Fig. 6. Internal oxidation as well depletion of Mn in metallic core, close to the metal/scale interface was observed. It caused the phase transformation from austenitic to ferritic structure. As the slowest partial process is a diffusion of metals in the steel, it explain a decrease of the corrosion rate during the last stage of the process.

5

The influence of chromium dopant of transport properties of [alfa]-MnS

Gilewicz-Wolter J., Grzesik Z., Wolter M., Dąbek J., Dudała J.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 2

127-134

EN

The influence of chromium on self-diffusion of cations in metal-deficit man-ganous sulphide, Mn1_yS, has been studied as a function of temperature and sulphur activity, using radio-tracer technique. It has been found that the rate of Mn self-diffusion in chromium doped Mn1_yS is higher than that in pure manganous sulphide and does not depend on equilibrium sulphur pressure. In addition, the activation energy of self-diffusion in Mn1_yS-Cr2S3 solid solution is lower than that in pure Mn1_yS. Both these results are in agreement with theoretical predictions based on simple defect model in Mn1_yS, assuming that the predominant defects in this sulphide are non-interacting, doubly ionized cation vacancies and electron holes.