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Elaboration de matériaux micro-nanostructurés à morphologies contrôlées, à base de tungstates, pour la photo-dégradation / Development of micro-nanostructured materials, with controlled morphologies, based on tungstates for photo-degradationDirany, Nadine 06 January 2017 (has links)
Dans le cadre du développement de nouvelles technologies pour la protection environnementale, et tout particulièrement pour la dépollution de l’eau ou de l’air, le présent travail de thèse porte sur la mise en œuvre de matériaux semiconducteurs à morphologies contrôlées, susceptibles d’activités photocatalytiques permettant la dégradation ou la transformation de molécules en milieux aqueux. Plusieurs types de synthèses conduisant à des morphologies diversifiées ont été mises en œuvre. Chaque matériau a été caractérisé par diffraction de rayons X, microscopies électroniques à balayage et en transmission, et parspectroscopie Raman. La réflectance diffuse a été utilisée pour déterminer les énergies de bandes interdites des matériaux. Compte tenu des propriétés déjà connues pour les tungstates de type MWO4, notre choix s’est orienté vers trois matériaux : le trioxyde WO3, le tungstate SrWO4 et un nouveau tungstate NaCe(WO4)2 ou Na0,5Ce0,5WO4. L’oxyde WO3 a été choisi comme matériau de référence. Pour ce matériau, deux types de morphologies ont été obtenues : des nanoplaquettes et des nanosphères. Le tungstate SrWO4 de structure scheelite a été synthétisé sous deux formes microstructurales : des sphères et des navettes. Un nouveau matériau a été synthétisé et caractérisé : le tungstate double Na0,5Ce0,5WO4 de structure scheelite. Pour cette nouvelle phase, trois morphologies 3D hiérarchisées ont été élaborées en utilisant la méthode hydrothermale en présence d’EDTA. Pour chaque morphologie observée, un mécanisme de germination-croissance est proposé. Les performances photocatalytiques des différentes formes morphologiques ont été évaluées lors de la dégradation de la rhodamine B (RhB) et du bleu de méthylène (BM), sous rayonnements UV et visible. L’efficacité photocatalytique des différentes microstructures a été étudiée en fonction du pH du milieu réactionnel. À partir des résultats obtenus, nous avons pu montrer la forte corrélation entre largeur de bande interdite et réactivité photocatalytique, mais aussi entre morphologies, tailles et propriétés photocatalytiques. Il est apparu que la dégradation reposesur deux mécanismes complémentaires : l’adsorption des molécules due à la porosité des microstructures et à leur morphologie, et la réaction photocatalytique due aux radicaux actifs générés par les paires e-/h+ photogénérées. Ainsi, la RhB se décompose en présence de SrWO4 et WO3 sous UV-C (254 nm) et UV-Vis (365 nm) respectivement. Le bleu de méthylène se dégrade en présence de NaCe(WO4)2 sous rayonnement solaire UV-Vis. / In the framework of the development of new technologies for environmental protection, andmore specially for the depollution of water or air, this work deals with the implementation ofsemiconductor materials with controlled morphologies, likely photocatalytic activities andtheir enabling the degradation or transformation of organic molecules in aqueous media.Several types of syntheses leading to diversified morphologies have been implemented. Eachmaterial was characterized by X-ray diffraction, scanning and transmission electronmicroscopies, and Raman spectroscopy. Diffuse reflectance was used to determine the bandgap of the materials. Given the properties already known for MWO4 tungstates, we chosethree materials: WO3 trioxide, SrWO4 tungstate and a new tungstate NaCe(WO4)2 orNa0.5Ce0.5WO4. The oxide WO3 was chosen as the reference material. For this material, twotypes of morphologies were obtained: nanoplates and nanospheres. The tungstate SrWO4 withscheelite structure was synthesized in two microstructural forms: spindles and spheres. A newmaterial was synthesized and characterized: double tungstate of Na0.5Ce0.5WO4 with scheelitestructure. For this new phase, three hierarchical 3D morphologies were developed using thehydrothermal method in the presence of EDTA. For each observed morphology, agermination-growth mechanism is proposed. The photocatalytic performances of the differentmorphological forms were evaluated during the degradation of rhodamine B (RhB) andmethylene blue (MB), under UV and visible radiation. The photocatalytic efficiency of thedifferent microstructures was studied as a function of the pH of the reaction medium. Fromthe results obtained, we have been able to show the strong correlation between band gap andphotocatalytic reactivity, but also between morphologies, sizes and photocatalytic properties.It has been shown that the degradation is based on two complementary mechanisms: theadsorption of molecules due to the porosity of the microstructures and their morphology, andthe photocatalytic reaction due to the active radicals generated by the photogenerated e-/ h+pairs. Thus, RhB decomposes in the presence of SrWO4 and WO3 under UV-C (254 nm) andUV-Vis (365 nm) respectively. Methylene blue degrades in the presence of NaCe(WO4)2under UV-Vis solar radiation.
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Bezpečnost práce a pracovní úrazy ve stavebnictví / Work safety and occupational injuries in the construction industryGettová, Zuzana January 2017 (has links)
The subject of this thesis was to compare injuries. First comparison accidents took place within the area of SK - NACE, their sources, and their causes in the Slovak Republic in the years 2012 - 2015. In the next step compared accidents within the area CZ - NACE, their sources, and causes in the Czech Republic in years 2011 - 2015. The last took place juxtaposition between the Slovak and Czech Republic.
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John Calvin's Eucharistic DoctrineJohnson, Martha L. January 1974 (has links)
No description available.
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Strukturální změny, strukturální nezaměstnanost a její řešení na karvinském trhu práce / Structural changes, structural unemployment and its solution on the labor market in the region KarvinskoKuželová, Kateřina January 2010 (has links)
This thesis is concentrated on the labor market in the past five years in region Karvinsko. The aim of thesis is to explore the ways in which is solved the imbalance of labor market in this region and to analyze effectiveness of spending money on active employment policy. The deman and supply sides of the labour market are detailly invastigated due to their great influence on the economic development. The thesis deals the efficiency of active employment policy in region Karvinsko, especially community services, retraining and socially useful jobs. Other part of my thesis is evaluation of the case study among the unemployed who are in evidence of the Job centre in Karvina.
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Analýza zadluženosti podnikové sféry dle jednotlivých odvětví v letech 2011-2015 / Analysis of debt financing by individual sectors for the period from 2011 to 2015Bělinová, Kristýna January 2016 (has links)
The main goal of this thesis is to find out whether is within individual industries preferred as the main source of financing debt financing for the period from 2011 to 2015. Then determine an industry that prefers foreign capital the most and select three representatives from that industry and analyze them in detail. Materials that are used for this work have the character of available public resources. The thesis is divided into three main parts. The theoretical part explains the indicators of the debt, theories to determine the optimal debt and other terms that are used in the third part. In the second part are described individual industries using the classification CZ NACE. Work is finished by the summary, which sums the findings
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Analýza indexů cen průmyslových výrobců v zemích střední a jihovýchodní Evropy pro účely oceňování dlouhodobého hmotného majetku nepřímou nákladovou metodou / The producer price index analysis for the purpose of assets estimation in Eastern EuropeUrbanovská, Aneta January 2012 (has links)
The thesis focus on the availibility of the time series of producer price index (PPI) in the selected countries from Eastern Europe. The PPI time series are necessary for assets price estimation. The aim of the thesis is to proove if there could be a "converter" between the PPI total and PPI for individual activity which could be used for creating time series in countries where the data are not available.
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Use of the CAS Standards by Career Services Directors at Four-year Public Colleges and UniversitiesRatcliffe, R. Samuel 29 July 2004 (has links)
The general purpose of this national study was to document career services director use of the CAS professional standards by institutional size, career services experience level, director experience level, director degree level, CAS standards awareness, CAS standards possession, and barriers to use. Also considered were the types of CAS standards use and satisfaction from use.
There were significant differences in CAS standards awareness by years of experience in career services and by years of experience as career services director. No differences were found with regard to perceived barriers to CAS standards use. Significant differences were discovered by institutional size, as well as by director degree level, regarding the extent of use and satisfaction from use of the CAS standards. Finally, key factors identified with regard to predicting CAS standards use included level of awareness, and the degree to which both previous CAS standards use had not been helpful and fear of finding non-compliance were perceived as barriers.
This study suggests that future research should concentrate on the reasons why practitioners are either satisfied or dissatisfied with use of the CAS standards and how the self-assessment guide is perceived and used. Additionally, an examination of how the different types of use influence perceived barriers merits consideration. / Ph. D.
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Analýza vývoje zaměstnanosti a determinant na ni působících v sektoru peněžnictví a pojišťovnictví se zaměřením na Českou republiku / The analysis of employment in the finance and insurance sector in the Czech RepublicHadrabová, Pavla January 2008 (has links)
The main goal of this thesis is the analysis of the employment progress in one of the most prospective sectors of the Czech economy -- the finance and insurance sector. The sector is characterised and classified and the main historic, economic and legislative determinants are addressed in the theoretical part of this thesis. The main focus of the subsequent analytical part of the thesis is the employment progress of the sector from the perspective of profession, age, culture and branch. An additional goal of the thesis is to compare the labour force demand of the finance and insurance sector with the structure of school-leavers who will come into their own through the sector. I conclude the thesis by evaluating future potential trends and employment progress.
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Vývoj inkasa daně z příjmů právnických osob v České republice / Development of corporate tax collection in the Czech RepublicDragomirecký, Erik January 2015 (has links)
The diploma thesis is aimed at analysis of corporate income tax, often discussed part of a tax system, which has lately been also subject of a tax competition. The primary objective of this work is analysis of collection of corporate income tax in the Czech Republic, according to taxpayers, and different economic sectors NACE. The secondary objective is analysis of tax deduction, especially donations, spending on research and development, and tax credit. The applied methods are analysis, comparison; out of the mathematical and statistical methods regression analysis is used. The analysis is done on years from 2005 to 2013.
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Analýza vývoje inkasa daně z přidané hodnoty v ČR / Analysis of revenues from value added tax.Sádovský, Martin January 2014 (has links)
This work is aimed on analyses of revenues from value added tax. These revenues are very important in public finance. The main goal of this work is to define independent variables of revenues and to create models for prediction revenues. For achieving this goal, it is used theory of tax revenues and mathematical - statistical methods of regression analysis and method of comparison. At first set the variables that affect the amount of revenues, then create equation for estimating revenues and eventually these predictions are verified on real data. Independent variable affecting revenues are GDP, GDP growth and tax rate. The best model for prediction is model based on GDP growth and difference in tax rate. We use method of comparison for searching conclusions in differences between tax duty and tax revenues. Tax duty is always higher than tax revenues. The uncollected tax revenues were in the values 6 - 22 mld. CZK. The final section search changes in the structure of tax duty in the years 2005 - 2012.
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