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Effect of external electric field upon charge distribution, energy and dipole moment of selected monosaccharide molecules

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Natural Science 2012年第5期4卷 276-285页

作者： Jozef Mazurkiewicz piotr tomasik Cracow College of the Health Promotion Cracow Poland Department of Chemistry and Physics University of Agriculture Cracow Poland

External electric field of 0.001, 0.01 and 0.05 a.u. changes distribution of the electron density in α- and β-D-glucose, α- and β-D-galactose, α- and β-fructopyranoses and α- and β-fructofuranoses, α- and β-D-ribofuranoses and α and β-D-xylo- furanoses. Hyper-Chem 8.0 software was used together with the AM1 method for optimization of the conformation of the molecules of monosaccharides under study. Then polarizability, charge distribution, potential and dipole moment for molecules placed in the external electric field of 0.000, 0.001, 0.01 and 0.05 a.u. were calculated involving DFT 3-21G method. Application of the external field induced polarizability of electrons, atoms and dipoles, the latter resulting in eventual reorientation of the molecules along the applied field of the molecules and the electron density redistribution at particular atoms. Increase in the field strength generated mostly irregular changes of the electron densities at particular atoms of the molecules as well as polarizabilities. Energy of these molecules and their dipole moments also varied with the strength of the field applied. Results of computations imply that saccharides present in the living organisms may participate in the response of the living organisms to the external electric field affecting metabolism of the molecules in the body fluids by fitting molecules to the enzymes. Structural changes of saccharide components of the membranes can influence the membrane permeability.

关键词： D-Fructose Dipole Moments D-Galactose D-Glucose Polarizabilty D-Ribose D-Xylose

Contribution to the understanding effects of weak electrical phenomena

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Natural Science 2010年第11期2卷 1195-1210页

作者： Józef Mazurkiewicz piotr tomasik Department of Chemistry and Physics University of Agriculture

Electronic emission spectra of N2, (N2)2, (N2)5 O2, (O2)2, (O2)5, H2O, (H2O)5, CO2, (CO2)2, CO2..H2O, NH3 and NH3.H2O situated in the electric field of 0.001, 0.005, 0.01 0.05 and 0.1 a.u. were simulated involving Monte Carlo optimization followed by the ZINDO/S approach. The simulated spectra showed irregular dependence on the energy of the electric field applied. Molecules without influence of the electric field emit in the vacuum ultraviolet region. Applied electric field only in case of (O2)5 generated transitions above 200 nm. The mapping of isosurface of the investigated molecules revealed that the electric field applied redistributed the charge densities in the molecules in the manner approximately parallel to the energy of the field. Applied electrical field resulted in an increase in the water acidity and ammonia basicity.

关键词： Electronic Emission Spectra Surface Effect ZINDO/S Spectra Simulations

Radioprotectors from pyrodextrins

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Chinese Science Bulletin 2010年第31期55卷 3556-3561页

作者： MICHALSKI Oskar BIDZINSKA Ewa BOROWSKI Micha DYREK Krystyna OLKO Pawe STOLARCZYK Liliana SWAKON Jan tomasik piotr WENDA ElZbieta Department of Chemistry and Physics University of Agriculture in Krakow Faculty of Chemistry Jagiellonian University Institute of Nuclear Physics of the Polish Academy of Sciences

Cornstarch heated in the range of 230-280°C depolymerized into pyrodextrins characterized by two-component EPR signals of relatively stable free *** thermally generated radicals could serve as efficient scavengers for free radicals generated from pyrodextrins with the 200 Gy dose of γ-*** most efficient traps/scavengers were produced from cornstarch at 250-280°*** data indicated incorporation of the OH groups to the *** groups most probably originated from the OH· radicals formed by the radiolysis of *** spectra provided evidence for trapping free radicals generated by γ-irradiation and for their subsequent annihilation on contact with *** affected radical processes occurring in pyrodextrins caused by γ-irradiation.

关键词：自由基清除剂玉米淀粉生产 EPR谱信号特征相对稳定双组分拾荒者数据表

Effect of external electric field upon charge distribution, energy and dipole moment of selected monosaccharide molecules

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Contribution to the understanding effects of weak electrical phenomena

Natural Science 2012年第5期

作者： Jozef Mazurkiewicz piotr tomasik

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Magnetocaloric effect of LaFe_(11.35)Co_(0.6)Si_(1.05) alloy

Natural Science 2010年第11期

作者： Józef Mazurkiewicz piotr tomasik

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Rare Metals 2022年第5期41卷 1563-1569页

作者： piotr Gebara Institute of Physics Czestochowa University of Technology42-200 CzestochowaPoland

The aim of the present paper was to study the large magnetocaloric effect observed in LaFe_(11.35)Co_(0.6)Si_(1.05)alloy. X-ray diffraction(XRD) result reveals a coexistence of two crystalline phases: a dominant La(Fe,Si)_(13)-type and a minor a-Fe(Co,Si). It is confirmed by the Mössbauer spectroscopy and microstructural observations accompanied by an energy-dispersive spectroscopy(EDS) analysis. The value of the magnetic entropy changes(|S_(M)|) in the vicinity of the Curie temperature(TC= 268 K) was calculated using thermomagnetic Maxwell relation, and it equals to 21.4 J·kg^(-1)·K^(-1) under the change in an external magnetic field of μ_(0)ΔH = 3T. The investigation of magnetic phase transition was carried out using the Landau theory, an analysis of the field dependences of the magnetic entropy change and universal scaling curve, revealing the second order of phase transition in the studied material.

关键词： X-ray diffraction M?ssbauer spectroscopy Magnetocaloric effect

Effect of TiB_2 Particles on the Tribological Properties of Stainless Steel Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 12-18页

作者： Iwona Sulima piotr Klimczyk piotr Malczewski Institute of Technology Pedagogical Universityul.Podchorazych 230-084 KrakwPoland Institute of Advanced Manufacturing Technology ul.Wroclawska 37A30-011 KrakwPoland

The AISI316L stainless steel composites reinforced with 2, 4, 6, and 8 vol% titanium diboride （TiB2） particles were sintered by the high pressure-high temperature method. Ball-on-disk method was carried out to study wear behavior of the composites. Tests were carried out at room temperature. The TiB2 particles improved the hardness and tribological properties of the composites. The friction coefficient of the composites decreased with the increasing content of TiB2. The reduction of the wear rate with the increasing of the content of TiB2 particles in the steel matrix was also observed. It is demonstrated that the friction coefficient of composites with the same content of TiB2 particles depend on the sintering conditions.

关键词： Metal matrix composites Titanium diboride Friction coefficient Bail-on-disk method

Advances in nutritional therapy in inflammatory boweldiseases:Review

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World Journal of Gastroenterology 2016年第3期22卷 1045-1066页

作者： Andrzej Wędrychowicz Andrzej Zając Przemysław tomasik Department of Pediatrics Gastroenterology and NutritionPolish-American Children’s HospitalJagiellonian University Medical College30663 KrakowPoland Department of Pediatric Surgery Polish-American Children’s HospitalJagiellonian University Medical College30663 KrakowPoland Department of Clinical Biochemistry Polish-American Children’s HospitalJagiellonian University Medical College30663 KrakowPoland

Inflammatory bowel diseases(IBD), including ulcerative colitis and Crohn's disease are chronic, life-long, and relapsing diseases of the gastrointestinal tract. Currently, there are no complete cure possibilities, but combined pharmacological and nutritional therapy may induce remission of the disease. Malnutrition and specific nutritional deficiencies are frequent among IBD patients, so the majority of them need nutritional treatment, which not only improves the state of nutrition of the patients but has strong anti-inflammatory activity as well. Moreover, some nutrients, from early stages of life are suspected as triggering factors in the etiopathogenesis of IBD. Both parenteral and enteral nutrition is used in IBD therapy, but their practical utility in different populations and in different countries is not clearly established, and there are sometimes conflicting theories concerning the role of nutrition in IBD. This review presents the actual data from research studies on the influence of nutrition on the etiopathogenesis of IBD and the latest findings regarding its mechanisms of action. The use of both parenteral and enteral nutrition as therapeutic methods in induction and maintenance therapy in IBD treatment is also extensively discussed. Comparison of the latest research data, scientific theories concerning the role of nutrition in IBD, and different opinions about them are also presented and discussed. Additionally, some potential future perspectives for nutritional therapy are highlighted.

关键词： Dietary factors Etiology Nutritionaltherapy Parenteral nutrition Exclusive enteral nutrition Induction therapy Maintenance therapy Inflammatorybowel disease

Solution of Inverse Heat Conduction Problem using the Tikhonov Regulariza-tion Method

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Journal of Thermal Science 2017年第1期26卷 60-65页

作者： piotr Duda Institute of Thermal Power Engineering Cracow University of Technology al. Jana Pawla Ⅱ 37 31-864 Krak6w Poland

It is hard to solve ill-posed problems, as calculated temperatures are very sensitive to errors made while calculating "measured" temperatures or performing real-time measurements. The errors can create temperature oscillation, which can be the cause of an unstable solution. In order to overcome such difficulties, a variety of techniques have been proposed in literature, including regularization, future time steps and smoothing digital filters. In this paper, the Tikhonov regularization is applied to stabilize the solution of the inverse heat conduction problem. The impact on the inverse solution stability and accuracy is demonstrated.

关键词： inverse problems, heat conduction, identification