Teses / dissertações sobre o tema "Zincate"
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Baillie, Sharon E. "Novel synthetic and structural advances in magnesiate and zincate chemistry". Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=18668.
Texto completo da fonteChohan, Zahid H. "Co-ordination chemistry of the 1,3-dithiole-2-thione (DMIT) and 2-one-4,5-dithiolato (DMIO) compounds". Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244990.
Texto completo da fonteHerd, Emma. "Alkali metal zincate chemistry : the importance of structure and stoichiometry on reactivity". Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24356.
Texto completo da fonteBalloch, Liam. "Towards understanding synergic s-block chemistry : new insights from zincate and magnesiate reactions". Thesis, University of Strathclyde, 2012. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=17205.
Texto completo da fonteRobertson, Sherryl G. "The zincate immersion process for plating aluminium: A kinetic, electrochemical and morphological study". Thesis, Robertson, Sherryl, G. (1995) The zincate immersion process for plating aluminium: A kinetic, electrochemical and morphological study. PhD thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/52750/.
Texto completo da fonteZIPPERIAN, DONALD CHARLES. "PHYSICAL AND CHEMICAL CHARACTERISTICS OF THE ZINCATE IMMERSION PROCESS FOR ALUMINUM AND ALUMINUM ALLOYS". Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184123.
Texto completo da fonteGarden, Jennifer Anne. "Advances in synthetic, structural and reaction chemistry of zinc and zincate complexes containing alkyl and/or amido ligands". Thesis, University of Strathclyde, 2014. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23171.
Texto completo da fonteSegale, Allan Davide. "Effetto del frenafiletti sul coefficiente d'attrito al serraggio in viti brunite". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Encontre o texto completo da fontePierret, Alexandre. "Fonctionnalisation à distance par métallotropie de dérivés benzyliques". Electronic Thesis or Diss., Université de Lorraine, 2023. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2023_0032_PIERRET.pdf.
Texto completo da fonteThis thesis presents a development of the remote functionalization reaction by metallotropic rearrangement on benzyl derivatives. The work is based on the use of a single metal reagent, a lithium triorganozincate, which allows the formation of two bonds C(sp3)-C(sp2) and C(sp3)-C(sp3) on sites 5 atoms apart in a single operation. The first chapter focuses on benzyl derivatives with an iodine in position 4 of the aromatic ring. Novel reaction conditions based on the use of a bio-based solvent are proposed. They allow to reach an unprecedented synthetic scope for such a reaction from these substrates. The influence of the solvent is also discussed. The second chapter is devoted to the mechanistic study by DFT of each step composing the reaction sequence studied previously. Thus, the halogen/metal exchange, the 1,2-migration of ligand or the metallotropic rearrangement are investigated with careful consideration of the solvent of the reaction. An experimental contribution completes this study. Finally, the extension of this transformation to benzylic heteroaromatic derivatives, in particular thiophenes, is the subject of the last chapter of this thesis. The reported work defines an approach of remote functionalization where a same toolbox, composed of a unique platform (halogenated thiophene bearing a benzyl phosphate) and an organometallic reagent of the same nature (lithium organozincate), offers several synthetic opportunities according to the experimenter's desires
Chaumont-Olive, Pauline. "Synthèse et développement de la réactivité des triorganozincates de lithium chiraux en addition nucléophile énantiosélective et application à la synthèse de produits bioactifs". Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR069/document.
Texto completo da fonteThe development of new asymetric methodologies have been widely explored during the last twenty years and in particular through organometallic reagents. Although these processes lead to excellent results in terms of enantiodiscrimination, the goal of this thesis was to develop new tools: cheap, chemoselective and allowing the access to the desired compounds with high yields and enantiomeric excesses. In this context, chiral lithium triorganozincates have been studied. Enantioselective nucleophilic 1,2 alkylation and arylation of aldehydes reactions, including (R)-N-(2-iso-butoxybenzyl)-1-phenylethanamine as the chiral ligand, have been optimized toward various aldehydes. The expected secondary chiral alcohols have been obtained with good yields (up to 83%) and high enantiomeric excesses (up to 99%).These processes have been then applied to the asymmetric synthesis of naturals and/or bioactive compounds as Spiromastilactone A, (R)-Neobenodine and (R)-Orphenadrine. Finally, the access to new amino-alcohols have been developed with the ultimate goal to engage those species as the chiral partner when reacting chiral lithium zincates with imines
Rouen, Mathieu. "Les Zincates de lithium en addition nucléophile énantiosélective". Rouen, 2011. http://www.theses.fr/2011ROUES035.
Texto completo da fonteVarious amidozincates were studied in enantioselective nucleophilic additions on carbonylated compounds. First, tetracoordinated zincates were considered. The optimization of the reaction was conducted on a racemic model (amide = TMP, complete conversion in THF at -78°C), then, the use of a chiral amide (derived from 3-aminopyrrolidine) gave access to enantioenriched alcohols with e. E. ’s up to 70% (60% yield). The stereochemical outcome of the reaction was examined thanks to the NMR technique. However, due to exchange phenomena between species, the exact structure of the inductive aggregate could not be determined. The use of tricoordinated zincates in the same kind of reaction was next undertaken. As previously, the optimal conditions of the reaction were determined on a racemic model to be transposed to an enantioselective version. For the latter, ten new chiral amines having an α-MBA pattern were synthesized. The presence of a heteroatom in the side chain of the amine, and in particular an oxygen atom in position δ from the nitrogen of the amide, led to the best results. The bulkiness of the ethereal function was found to play a crucial role, the presence of an iso-propoxy group affording the highest inductions (up to 90% ee). Finally, various aldehydes and zinc derivatives (R2Zn) were engaged and enantioselectivities up to 95% could be reached
Greco, Jeffrey Francis. "Preparation, reactivity, and structural studies of zincated C-nucleophiles". Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3207757.
Texto completo da fonteHansson, Robert. "Phase equilibria of zincite containing systems relevant to zinc/lead smelting /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19174.pdf.
Texto completo da fonteFerrari, Jean Vicente. "Contaminação com sal de cloreto e cromatização da superfície do aço zincado no processo não-contínuo de zincagem por imersão a quente: influência no desempenho de tintas e determinação de pré-tratamentos para pintura adequados". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-05092006-124730/.
Texto completo da fonteThe batch galvanizing process (BGP) can lead to surface contamination of hot-dip galvanized steel (HDGS) with chloride residues. If these residues are not effectively eliminated, they can influence negatively on the performance of duplex systems (galvanizing plus painting). It is known that the chromate quenching is widely used in the BGP, however the effect of this post-treatment on the performance of duplex systems is not well established yet. In this sense, this work aimed: I to verify the contamination degree of HDGS with chloride salt due to the BGP itself; II to verify the effects of the chloride salt contamination and chromate quenching on the performance of paints applied on HDGS; and III to determine the suitable surface preparation for painting in order for obtaining a good paint performance applied on HDGS. The adopted methodology to achieve goal I involved the galvanizing of steel plates in different service renderings with BGP, in different conditions. These HDGS plates were submitted to the qualitative energy dispersive microanalyses (EDS) in scanning electron microscopy (SEM) and to the determination of superficial chloride contents by the boiling water extraction method. From the obtained results, the conditions in the BGP that potentially lead to greater surface contamination of HDGS with chloride salt were determined. Thus, to achieve goals II and III, steel plates were galvanized under the maximum chloride salt contamination condition and part of them were submitted to chromate quenching. After that, a great part of these HDGS plates (chromated or non chromated quenching) was submitted to the surface preparations for painting through organic solvent cleaning, high pressure hydroblasting, sweep blasting and handled scrub cleaning with an abrasive sponge and hot distilled water. Finally, the HDGS plates, including those not submitted to the surface preparations for painting, were painted with one coat of primer plus one coat of finishing paint. The HDGS painted plates were submitted to accelerated (distilled water immersion and humidity chamber exposure) and non accelerated (atmospheric exposure) corrosion tests and their performance were verified by means of traditional tests (degree of blistering and paint adhesion) and electrochemical measurements (open circuit potential, polarization curve and electrochemical impedance spectroscopy E.I.S.). Before painting, some HDGS plates were submitted to tests for physical (microstructural and morphological analyses in MEV and surface roughness), chemical (EDS, X-ray diffraction and superficial chloride contents by the boiling water extraction method) and electrochemical characterization. The obtained results allowed verifying that the additional application of solid ammonium chloride salt during the BGP tends to increase the degree of superficial chloride contamination of the HDGS and, the water and/or chromate quenching also contribute for this contamination. In general, the chromated HDGS presented worst performances. The high pressure hydroblasting and the handled scrub cleaning with an abrasive sponge and hot distilled water were the surface preparations for painting that provided the best performances of paint systems.
Pedroso, Danieli Cristina. "Análise de causas de rejeições de peças de aço zincadas a quente". Universidade Presbiteriana Mackenzie, 2009. http://tede.mackenzie.br/jspui/handle/tede/2745.
Texto completo da fonteIn this work the causes of rejection of lots of artifacts from the company Produto para Linhas Preformados, PLP, were analyzed which are made of steel SAE 1010 and SAE 1020 and zinc coated by hot-dip galvanizing. Lots of samples from different manufacturers were selected, with different chemical composition and geometry, but belonging to rejected lots and approved lots in accordance with usual market standards. The rejections are due to problems related to the adhesion of the layer of zinc. The samples were submitted to optical microscopy test, scanning electron microscopy and X-ray diffractions for comparative checking of between the structures of zinc formed layers by hot -dip galvanizing. To verify the corrosion in coating failure, corrosion tests were performed in three different environments: urban environment considered to be low-polluted; environment simulating sea water, salt spray. There is no failure evidence between the zinc coating and the substrate structure; irregular coatings and not very well defined phases were found in the rejected parts. In regions with failures, the results show a behavior similar to the literature with the rapid formation of rust at the beginning of the exposure followed by a show oxidation.
Neste trabalho foram analisadas as causas da rejeição de lotes de artefatos da empresa Produto para Linhas Preformados, PLP, fabricados com aços SAE 1010 e SAE 1020 e zincados por imersão a quente. Foram selecionadas amostras de lotes de fabricantes diferentes, com composição química e geometrias distintas, pertencentes a lotes rejeitados e a lotes aprovados de acordo com normas usuais de mercado. As rejeições se devem a problemas relacionados a aderência da camada de zinco. As amostras foram submetidas a exames por microscopia óptica, microscopia de varredura e análises por difração de raio-X para verificação comparativa entre as estruturas das camadas de zinco formadas no processo zincagem por imersão a quente. Para verificar a corrosão nas falhas de revestimento de zinco, foram realizados ensaios de corrosão em três ambientes diferentes: ambiente considerado urbano de baixa poluição; ambiente simulando água do mar; câmara de névoa salina. Não há indício de relação entre a falha nos revestimentos de zinco e a estrutura do substrato; revestimentos irregulares e com fases não muito bem definidas foram encontrados nas peças rejeitadas. Nas regiões com falha, os resultados evidenciam um comportamento semelhante ao da literatura, com formação rápida de ferrugem no início da exposição das peças seguida por uma oxidação lenta.
Korzenowski, Christa. "Tratamento de efluentes ácidos e alcalinos de zincagem eletrolítica por eletrodiálise". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1996. http://hdl.handle.net/10183/159031.
Texto completo da fonteThe present work proposes throught of use of electrodialysis a method of treatment of wastewater resulting from acidic and alkaline zinc electroplating without producing of rejectable metallic hydroxide trough convencional treatment o f effluents. lnitially zinc and cloride synthetic wastewaters and after cyanide and hydroxide syntetic wastewaters were separately studied. In this eflluents was determined the best conditions of use of electrodialysis, how the best time, the best current density, the best temperature, and the best pH, watching fenomene how concentration polarization, limiting current density, influences of pH, temperature and agitation. From the results obtained in these study, we use the electrodialysis to see a recuperation of each ion using two membranes diferents in the same sistem. The wastewater pollutants concentrations were chemically analysed, before and after each treatment estage lt was obtained, as final wastewater, a solution with zmc, cloride and cyanide concentrations practilly zero, and another solution contained separately big quantity of zinc, cloride, cyanide, and hydroxide all of witch may be reused in the electrodeposition of zinc.
Rodrigues, Tania Regina Inacio. "Perda de carga provocada por engate rapido em tubulações de aço zincado". [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258406.
Texto completo da fonteDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil
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Resumo: Amplamente utilizados em conjuntos portáteis de irrigação, os tubos de aço zincado com engate rápido proporcionam facilidade na operação e manuseio destes sistemas. Uma dificuldade frenquentemente encontrada pelos projetistas para o dimensionamento hidráulico dessas tubulações, refere-se a avaliação da perda de carga provocada pelo engate, por não dispor do valor do coeficiente de perda de carga. O presente estudo tem como objetivo determinar os coeficientes de perda de carga "K", para as condições dos tubos existentes no mercado nacional. Um estudo experimental foi conduzido no Laboratório de Hidráulica e Mecânica dos Fluidos da Faculdade de Engenharia Civil (FEC) da Universidade Estadual de Campinas, considerando tubos em aço zincado com engate rápido de diâmetros entre 0,050 a 0,150 m de três fabricantes diferentes. Como resultado desta pesquisa foram determinados valores dos coeficientes variando de 0,780 a 0,088 influenciados pelo diâmetro da tubulação e o fabricante, que serão portanto indicados para os projetistas deste sistema
Abstract: Widely used in portable irrigation pipelines, the steel galvanized pipes with quick couples make these systems of easier operation and maintenance. Often, project engineers find troubles for calculating these pipes. That is due to get the correct value of the couple head loss, as they do not have the coefficient to calculate it. The main objetive of this study was the determination of the head loss coefficients in the coupler considering Brazilian pipes. An experimental research was conducted in the Hidraulic and Fluids Mechanic Laboratory of CivilEngineering College at the University of Campinas, using quick couples steel galvanized pipes, with diameters ranging from 0,050 to 0,150m, and from three differents factories. As a result of this research, the had loss coefficients values were from 0,78 and 0,088, influenced by the diameter and the factory and these are proposed to be used in future projects
Mestrado
Recursos Hidricos
Mestre em Engenharia Civil
Denichoux, Aurélien. "Réarrangements d'époxydes acétyléniques : applications synthétiques". Paris 6, 2006. http://www.theses.fr/2006PA066464.
Texto completo da fonteBernardes, Andrea Moura. "Processo simplificado de tratamento de efluentes líquidos de zincagem eletrolítica contendo soluções de cianeto". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1989. http://hdl.handle.net/10183/130129.
Texto completo da fonteThe present work proposes a treatment of wastewater resulting from alkaline zinc electroplating of steel and/or cast iron pieces without segregation of the different wastewaters types. Initially cyanide synthetic wastewaters and hexavalent chromium synthetic wastewaters were separately studied. The relationship between ORP and pH, ORP and pollutants concentration, ORP and reducing and/or oxidizing agent added volume was determined, and the reaction kinetics between Cr +6 and reand CN and oxidizing agent (NaOCl) was studied. The best treatment process for each one of these wastewaters was established. From the results obtained in these studies, the best treatment for the process wastewaters mixture was determined. ln this case the sequence of steps followed were cyanide oxidation with NaOCl, hexavalent chromium reduction at alkaline pH with Na 2s 2o4 and Feso4 and metals precipitation with SEPARAN AP 273 Prernium as flocculation agent. Before and after each treatment stage, the wastewater pollutants concentrations were chemically analysed. It was obtained, as final wastewater, a treated solution with iron, zinc, cyanide and chromium concentrations below the pollutants discharge limits determined by Secretaria Especial do Meio Ambiente (SEMA).
Bittencourt, Sérgio Deitos. "Tratamento de efluentes de zincagem eletrolítica ácida por eletrodiálise : utilização de densidades de corrente inferiores e superiores a limite". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180147.
Texto completo da fonteThe metalfinishing process is one of the industrial processes with the highest disposal of contaminants in the environment. The produced waste contains a high level of metals and salts and requires treatment, in order to reuse chemicals and water in the process. New technologies for the treatment of waste contaminated by metals are being researched and the electrodialysis (ED) has been found effective to water recovery and electrolyte concentration. In this electrochemical membrane separation process, the ionic species in solution are transported through ion-exchange membranes by applying an electric field, which allows the separation of cations and anions. This process has the advantage of removing metals, recovering, at the same time, water. One important parameter to be assessed is the transport through the membranes, which has been analyzed in this study by using the electrochemical characterization technique called chronopotentiometry. In this process, a current pulse is applied between two electrodes positioned on the extremities of an electrochemical cell and the potential drop through the membrane is measured. The study focus was the use of currents below and above the limit current, which were obtained through the current-potential curves (CVC). Bench and pilot systems were used for the treatment of the washing waters used in the processes of acid zinc electroplating and synthetic solutions with and without the presence of additives. Commercial membranes provided by Hidrodex™ (cation membrane - HDX 100 and anion membrane - HDX 200) were used. The results have shown that the electrodialysis is efficient for the removal of metallic ions and for the recovery of water. The trials performed with different current densities showed that the electrodialysis removed at least 98% of the contaminants.
Costa, Josiane Soares. "Avaliação do revestimento de conversão à base de zircônio e tanino sobre aço zincado por eletrodeposição". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/96644.
Texto completo da fontePre-treatment of metal surfaces is used to increase the performance against corrosion. Many pieces of different sizes are chromatid, resulting in a large amount of wastewater and solid waste generated from the initial to the final stages of the process. Hexavalent chromium is toxic and carcinogenic. This goes against the great global concern today: sustainability and reducing environmental impact. New sustainable processes have been studied to reduce environmental impacts. Therefore, this paper presents the performance of zirconium nanoceramic based coatings on zinc substrates obtained by electrodeposition in acidic and alkaline baths. A nanoceramic coating and subsequent application of a potential tannin yellow dye was evaluated in relation to the chromate coatings (CrIII and CrVI). The coating "nano Zr" is obtained through conversion based solution hexafluorzirconic acid forming nanostructured layers of zirconium oxide on the surface. The use of Zr based coating improves the corrosion resistance of galvanized steel. The addition of a tannin allows visualization of the coating "nano Zr" on galvanized parts, because its layer is originally transparent. The EIS and polarization tests showed an equivalent coating performance "nano Zr" with further application of the coating tannin CrIII for alkaline and acidic parts galvanized coating. In addition, it was achieved the expected yellow for these samples, with the application of the coatings in two steps. The results showed that the use of this type of coating is promising in the replacement of chromating process.
Zhao, Peng. "The Attempted Synthesis of Carba-Nicotinic Acid Mononucleotide Methyl Ester using the Zincke Reaction". University of Toledo Health Science Campus / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=mco1488576282701401.
Texto completo da fonteDaltro, Adnauer Tarquínio. "Soldagem a arco elétrico com proteção gasosa em juntas de chapas finas de aço". Universidade de São Paulo, 2000. http://www.teses.usp.br/teses/disponiveis/88/88131/tde-16092016-160549/.
Texto completo da fonteThe thin sheet steels, coated or not, has been widely used nowadays, mainly the hot dip galvanized steel sheets. It\'s observed as in the mechanic and automobilist industry as in the civil construction that in manufacturing of pieces and structures employ welding procedures. The aim of this work is to establish procedures to gas metal are welding with short circuit transfer of thin sheet steel elements, not coated and zinc-coated steel, in order to get junctions of acceptance quality and reduction of welding stress and distortion. This distortion arise of the thermal cycles that occur during the welding. In terms of the weld quality is defined the best consumables combination available in the market, in such a way to reduce the weld defects like porosities, spatters, cracks and loss of covering. To galvanized steel sheets, the combination: wire ER70S-3 and mixture 8%CO2 + 92% Ar showed the best performance. Three techniques were employed for control and reduce the welding distortion. One that using a spot heat sink following the arc, in this case the cooling jet, was more efficient that others techniques.
Viana, Gustavo Henrique Ribeiro. "Estudos para a síntese da viscosamina, de análogos oxigenados e de novos sais de piridínio quirais usando a reação de zincke". Universidade Federal de Minas Gerais, 2008. http://hdl.handle.net/1843/SFSA-867UVE.
Texto completo da fonteEste trabalho foi dividido em duas partes. A primeira parte trata da tentativa de síntese do alcalóide marinho viscosamina, um macrociclo de ocorrência natural, e de análogos oxigenados. A segunda parte trata da obtenção de sais de piridínio quirais inéditos. A reação de Zincke foi a alternativa escolhida para a realização da etapa chave que levaria à síntese da viscosamina e de seus análogos oxigenados bem como para a introdução do estereocentro diretamente ligado ao nitrogênio nos sais de piridínio quirais. Os estudos para a obtenção da viscosamina não levaram à síntese total deste alcalóide. Além das diversas dificuldades enfrentadas durante a tentativa para sua obtenção, sua síntese foi descrita pela primeira vez por outro grupo de pesquisa no decorrer do trabalho. Portanto, optou-se por realizar a síntese de análogos oxigenados inéditos desse composto. Destes estudos, Um macrociclo inédito oxigenado foi obtido com baixo rendimento. Durante as tentativas de síntese de análogos da viscosamina obteve-se um composto oxigenado inédito análogo ao alcalóide marinho teonalidina C. Quanto à síntese dos sais de piridínio quirais, foi possível obter compostos inéditos com diferentes grupos alquila de cadeia longa ligados à posição 3 do anel piridínico. Conseguiu-se também demonstrar a viabilidade do uso de microondas tanto para a síntese de sais de Zincke na ausência de solvente quanto para a síntese de diversos sais de piridínio quirais já conhecidos usando 1-butanol ou água como solvente da reação. O uso da irradiação de microondas para a obtenção de compostos na ausência de solvente ou em meio aquoso representa um importante avanço no que se refere ao desenvolvimento de metodologias mais seguras, ecologicamente corretas e que consomem menos energia quando comparados aos métodos tradicionais de síntese. Finalmente, foi avaliada pela primeira vez a atividade antimicrobiana de sais de Zincke. Dos onze sais testados pelo menos nove deles apresentaram alguma atividade contra uma das bactérias testadas.
Berville, Mathilde. "Radicaux π-conjugués pour la construction et le contrôle redox d'assemblages moléculaires". Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF050/document.
Texto completo da fonteConduction in organic materials is a current challenge addressed by many research groups in order to adapt the structure of materials to their expected applications. The understanding of the conduction requires the exploring of conjugated pi-radicals which are the smallest vector for charge delocalisation. This work focuses on the synthesis of electro-active materials, precursors of conjugated pi-radicals for the self-assembly and the redox control of the physical properties of materials. The first chapter introduces intermolecular interactions that are specific of conjugated pi-radicals and the relevant physical evidences characterizing the interactions. The use of these interactions is then illustrated by selected literature examples. The second chapter describes the synthesis of viologens and the formation of assembly in solution. The third chapter deals with the development of synthesis of bis-viologen cyclophanes and their studying both in the solid state and in solution
Zincke, Fabian [Verfasser], Ulrike [Gutachter] Stein, Edda [Gutachter] Klipp e Stephan Michael [Gutachter] Feller. "Biomarker based therapies in high risk cancer patients - MACC1 as molecular target / Fabian Zincke ; Gutachter: Ulrike Stein, Edda Klipp, Stephan Michael Feller". Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1202775608/34.
Texto completo da fonteCarpinelli, Nicolo. "Definizione di una metodica per il controllo in continuo delle proprietà meccaniche su prodotti di acciaio laminati e zincati mediante sensore di rilevamento della magnetizzazione residua e sviluppo del ciclo produttivo di un materiale bifasico". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6936/.
Texto completo da fontePokhrel, Lok R., e Phillip R. Scheuerman. "Ecological Risk Assessment of Zinc Oxide Nanoparticles". Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/2962.
Texto completo da fonteJohansen, Jonathan Frederick. "Mathematical modelling of primary alkaline batteries". Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16412/1/Jonathan_Johansen_Thesis.pdf.
Texto completo da fonteJohansen, Jonathan Frederick. "Mathematical modelling of primary alkaline batteries". Queensland University of Technology, 2007. http://eprints.qut.edu.au/16412/.
Texto completo da fonteLam, Jonathan K. "Part I| Ring-Rearrangement Metathesis of Himbert Arene-Allene Cycloadducts for the Rapid, Modular Construction of Complex Molecular Scaffolds. Part II| Application of Zincke Aldehydes Toward the Synthesis of Gelsemine". Thesis, University of California, Irvine, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3646740.
Texto completo da fonteDeveloping new synthetic methods and strategies is an important area of research in organic chemistry. Especially useful are transformations that rapidly and rationally generate complex molecular architectures, with multiple new bonds and new stereocenters, from simple, achiral and modular precursors. This dissertation discusses the synthetic investigation and exploitation of two such reactions.
In PART I, the intramolecular Diels–Alder (IMDA) reaction of aromatic dienes and allene dienophiles, utilized in conjunction with ring-rearrangement metathesis (RRM) to prepare angularly-fused polycyclic lactams, is discussed. The mechanism of the IMDA reaction was investigated with the aid of computational molecular modeling. The reaction was determined to proceed through a concerted mechanism; however, competing radical pathways accounted for stereochemical infidelity and fragmentation observed for some substrates.
An improved, modular synthesis of the precursors was developed to directly couple aromatic amines with the allene fragment precursor, which allowed for the preparation of a small library of heterocyclic compounds. This two-step protocol generates topologically interesting structures, containing two or more new rings, and two new sp3 stereocenters. Computational modeling also guided the development of the unknown analogous reaction for allenyl ketone substrates, which yield carbocyclic products.
Unexpected stereoselectivity and reactivity observations were made in the alkene metathesis reaction, which could not be readily explained. Computational studies were able to elucidate a subtle yet fundamental relationship between reaction mechanism and length of alkene tether in these types of substrates.
In PART II, efforts toward the synthesis of the alkaloid natural product gelsemine are discussed. The synthetic strategy employs a Zincke aldehyde rearrangement/IMDA cascade previously developed by the Vanderwal lab. Using 4-phenylpyridine as a model system, the expected transformation successfully gives an advanced synthetic intermediate lacking only the oxindole substructure, and the key C3–O4 and C5–C16 bonds present in the target. Elaboration of this intermediate toward the target is detailed.
A number of protected 4-(2-aminophenyl)pyridine analogues were prepared to facilitate oxindole formation and circumvent later stage complications that arose in the model system. These compounds all either failed to undergo Zincke salt formation, pyridinium ring-opening, or subsequent rearrangement/IMDA, thus delineating the synthetic boundaries of this type of chemistry.
BILLOT, XAVIER. "Utilisation de la reaction de zincke pour la synthese d'oligomeres lineaires ou macrocycliques de type polypyridinium, analogues de produits marins cytotoxiques. Synthese des (r)-niphatesines c et d, de la motuporamine a et de la (r)-haliclorensine". Paris 11, 1999. http://www.theses.fr/1999PA112334.
Texto completo da fonteMehmandoust, Maryam. "Synthèse de dihydro-1, 2 pyridines et d'équivalents de sels de dihydro-2, 5 pyridinium à partir d'amines primaires chirales : application à la synthèse énantiosélective de dérivés d'isoquinuclidines et de pipéridines 2-substituées". Paris 11, 1989. http://www.theses.fr/1989PA112254.
Texto completo da fonteThe reaction of chiral primary amines with 2,4-dinitro phenyl pyridinium chloride, according to Zincke's procedure, leads to chiral pyridinium salts which can be reduced with NaBH4 in an alkaline medium to the corresponding 1,2-dihydropyridines bearing the chiral substituent on the nitrogen. Cycloaddition reactions of these dihydropyridines with methyl acrylate give isoquinuclidines in 20-33% d. E. Absolute configuration of optically pure isoquinuclidines separated from this diastereoisomeric mixture is established. On the other hand, reduction of pyridinium salts derived from amino alcohols such as (R)-phenyl glycinol in the same conditions leads to new oxazolidine-type intermediates which can be considered as 2,5-dihydropyridinium salt equivalents. Stereoselective alkylation followed by removal of the chiral auxilliary provides a simple access to enantio merically pure 2-alkyl 1,2,3,6-tetrahydropyridines. The usefulness of this methodology for the construction of optically pure piperidine derivatives is illustrated by the synthesis of (R)-(+)-anatabine and (S)-(+)-coniine
Hales, Matthew Cameron. "Synthesis and characterisation of substituted smithsonite and calcite". Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/16643/1/Matthew_Hales_Thesis.pdf.
Texto completo da fonteHales, Matthew Cameron. "Synthesis and characterisation of substituted smithsonite and calcite". Queensland University of Technology, 2008. http://eprints.qut.edu.au/16643/.
Texto completo da fonteDietze, Markus. "Die Lukasevangelien auf Caló. Die Ursachen ihrer Sprachinterferenz und der Anteil des Spanischen". Master's thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-152855.
Texto completo da fonteWang, Rainey Yu. "The morphology study of zinc electrodeposits from alkaline zincate solutions". 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=449830&T=F.
Texto completo da fonteChen, Po-Wei, e 陳柏瑋. "Preparation calcium zincate composite and its application to a Ni/Zn battery". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/76306082666603047808.
Texto completo da fonte明志科技大學
化工與材料工程研究所
97
The purpose of this work is to improve the life-cycle of a Zn electrode on a secondary Ni/Zn battery. As we know, the application of the secondary Zn electrode on the rechargeable Ni/Zn battery is still limited because of the dendritic growth, the shape change, and the high solubility in a concentrated KOH solution for the Zn electrode. The calcium zincate powders used as active materials (so-called CP-ZnCa) for the secondary Zn electrode were prepared by a chemical co-precipitation (CP) method. The preparation condition of CP-ZnCa active materials was at 60oC and pH=12. Moreover, the CP-ZnCa powders show higher surface area (28.66 m2 g-1) and smaller particle size, and the chemical uniformity of the CP-ZnCa powers was extremely good. The characteristic properties of CP-ZnCa powders were systematically examined by thermal gravimetric analysis (TGA), X-ray diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) measurement, Transmission electron microscope (TEM), and micro-Raman spectroscopy. As a result, the electrochemical performance of CP-ZnCa powders was much better than that of BM-ZnCa powders. In order to avoid the dendritic growth of the secondary Zn electrode, the zinc electrodes generally need a suitable micro-porous polymer membrane during the charge/discharge process. In this work, we prepared two types of new micro-porous polymer membranes, namely, the micro-porous PVA/PVC and PVA/PEO composite polymer membranes, for the secondary zinc electrode. The secondary zinc electrode by using CP-ZnCa powders coated on the brass screen wrapped with the micro-porous PVA/PVC or PVA/PEO composite polymer membranes was prepared and studied. Using cycle voltammetry to examine the cycle-life of the secondary zinc electrode, it was found that it exhibited at least 200 life-cycle. In addition, the secondary Ni/Zn battery was prepared and examined by using galvanostatic test method at the C/5 charge and the C/5 discharge rates. The experimental result revealed that the secondary Ni/Zn battery showed at least 50 life-cycle; moreover, the current and energy efficiencies of the Ni/Zn battery were about 80% and 70%, respectively.
Meng-HanYang e 楊孟翰. "Synthesis and characterization of nano-zincite with different morphologies". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/37611175096721365916.
Texto completo da fonte國立成功大學
地球科學系
102
Zincite (ZnO), which has many potential properties, such as wide direct band gap (~3.37 eV) and high-exciton binding energy (~60 meV), has been widely investigated. In this study, zincite with two crystal morphologies (nano-particle and nano-rod) is synthesized via the chemical precipitation and hydrothermal methods. The zincite nano-particle and nano-rod both have a hexagonal structure with the wurtzite-type. The zincite nano-particle has a particle size around 20~60 nm and nano-rod has a particle size of 15~35 nm in width and 100~150 nm in length, which are fabricated by chemical precipitation method. The zincite micron-rod synthesized via hydrothermal method has a larger particle size of 400~800 nm in width and 800~6,000 nm in length. The band gap of zincite nano-particle and nano-rod is 3.1~3.2 eV. The BET result shows that the specific surface area of the zincite nano-particle and nano-rod is 30.39 m2/g and 23.99 m2/g, respectively. It is also observed that both morphologies of nano-zincites exhibit good photocatalytic activity under UV-light illumination. The photodegradation on methylene blue is ~95 % within 170 and 105 min for zincite nano-particle and nano-rod, respectively. Hence, nano-zincite is a superior photocatalyst, effective for clean removal of organic dyes, and maybe suitable for wastewater treatment applications.
Zortea, Laura. "Caratterizzazione microstrutturale e meccanica di rivestimenti colorati innovativi ottenuti tramite bagni di zincatura con l'aggiunta di titanio". Doctoral thesis, 2013. http://hdl.handle.net/11573/917219.
Texto completo da fonteMonteiro, Fernando Jorge Mendes. "A electrodeposição sobre alumínio : tratamentos prévios em solução modificada de zincato". Doctoral thesis, 1986. http://hdl.handle.net/10216/12781.
Texto completo da fonteMonteiro, Fernando Jorge Mendes. "A electrodeposição sobre alumínio : tratamentos prévios em solução modificada de zincato". Tese, 1986. http://hdl.handle.net/10216/12781.
Texto completo da fonteMontuori, Mario. "CORROSIONE DI ARMATURE IN ACCIAIO E ACCIAIO ZINCATO SU STRUTTURE IN CALCESTRUZZO ARMATO RINFORZATE CON FRP". Tesi di dottorato, 2008. http://www.fedoa.unina.it/4017/1/montuori%29.pdf.
Texto completo da fonte"Perda de carga provocada por engate rapido em tubulações de aço zincado". Tese, Biblioteca Digital da Unicamp, 1998. http://libdigi.unicamp.br/document/?code=vtls000184082.
Texto completo da fonteZincke, Horst [Verfasser]. "Zur Alteration der Immunogenität von Nierentransplantaten beim Hund und beim Menschen / vorgelegt von Horst Zincke". 2006. http://d-nb.info/98060477X/34.
Texto completo da fonteCokoja, Mirza [Verfasser]. "Nanometallurgy in organic solution: organometallic synthesis of intermetallic transition metal aluminide and -zincide nanoparticles / vorgelegt von Mirza Cokoja". 2007. http://d-nb.info/985056525/34.
Texto completo da fonteRodrigues, Joana Isabel da Silva. "Recuperação de metais de águas contaminadas por processos baseados na utilização de extratos das plantas Cistus ladanifer e Erica andevalensis". Master's thesis, 2019. http://hdl.handle.net/10400.1/14894.
Texto completo da fonteNowadays, due to the greater concern about environmental problems and considering the restrictions on the discharge of effluents contaminated with metals, it is essential to develop sustainable and effective processes aiming the recovery of metals from waste streams. At the same time numerous plant species have been described as metal tolerant and accumulators, as is the case of Erica andevalensis and Cistus ladanifer, both found in Portugal in the São Domingos mining area. That capacity of those plants has been explored in the present work aiming the recovery of strategic metals from aqueous solutions. To achieve that purpose the main objectives of this research included: (1) to assess the use of hydroalcoholic plant extracts directly in metal contaminated effluents and artificial solutions for the removal / recovery of the metals of interest and (2) to assess the use of phenolic compounds extracted from those plants diluted in organic solvents for the removal / recovery of metals by solvent (also known as liquid-liquid) extraction technique. The tests in which hydroalcoholic extracts of E. andevalensis and C. ladanifer were added to unimetallic solutions prepared with HCl and H2SO4, showed that the platinum group metals (Pt and Pd) and gold were removed (20 to 100%) from both matrices, as well as silver (90 to 100%) in H2SO4. The same happened with iron(III) but in a lower range of removal (15 to 25%). On the other hand, the addition of these extracts to a zinc plating effluent moderately contaminated with Zn an Fe resulted in no removal of Zn and low removal of Fe (≤ 21%). On the contrary, when the hydroalcoholic extract of C. ladanifer was added to an extremely concentrated acid mine drainage (AMD) collected in the São Domingos mining area, all metals were removed in medium percentages (Al: ~ 63%, Zn: ~ 51%, Fe: ~ 52%, Cu: ~ 43% and Mn: ~ 36%); as with the extract of E. andevalensis, albeit in lower percentages (Al: ~ 10%, Zn: ~ 16%, Fe: ~ 21%, Cu: ~ 6% and Mn: ~ 1%). The solvent extraction tests aiming metals recovery from the zinc plating effluent showed that for the extracts of C. ladanifer prepared with Shell GTL and Octanol, or only Shell GTL, there was low extraction of Fe (<10%) and no extraction of Zn from the zinc plating effluent. On the other hand, when using ethyl acetate enriched with C. ladanifer phenolic compounds, the best yield on phenolic compounds was obtained with 80% (v/v) acetone in acidified water (1.2 M HCl) and there was a direct relationship between the concentration of phenols in ethyl acetate and the efficiency of iron and zinc extractions (which reached ~ 34% and ~ 56%, respectively). Moreover, in tests with phenolic compounds transferred to ethyl butyrate, butyl acetate, decanol and octanol, extraction efficiencies of Zn and Fe (<25%) were relatively lower for both plants than when ethyl acetate was used.
Este trabalho foi financiado por fundos nacionais através da FCT - Fundação para a Ciência e Tecnologia - no âmbito do projeto Metalchembio (no. 29251) e do projeto UID / Multi / 04326/2019 e co-financiado pelo Programa Operacional Regional do Algarve (CRESC Algarve 2020), através do Portugal 2020 e do Fundo Europeu de Desenvolvimento Regional (FEDER).
Roy, Debangsu. "Exchange Spring Behaviour in Magnetic Oxides". Thesis, 2012. http://etd.iisc.ac.in/handle/2005/3172.
Texto completo da fonteRoy, Debangsu. "Exchange Spring Behaviour in Magnetic Oxides". Thesis, 2012. http://hdl.handle.net/2005/3172.
Texto completo da fonteDietze, Markus. "Die Lukasevangelien auf Caló. Die Ursachen ihrer Sprachinterferenz und der Anteil des Spanischen". Master's thesis, 2012. https://tud.qucosa.de/id/qucosa%3A28299.
Texto completo da fonte