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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The biosynthesis of complex III in yeast

Kreike, Jan. January 1982 (has links)
Thesis (Doctoral)--Universiteit van Amsterdam, 1982.
52

Analysis of movement of the maxilla with facemask protraction in the maxillary deficient class III patient a geometric model for finding the change in the maxillary centroid /

Christensen, Bret B., January 1999 (has links)
Thesis (M.S.)--University of Louisville, 1999. / School of Dentistry, Program in Oral Biology. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
53

Síntese de calcogenoacetilenos catalisada por haletos de In III

Giovenardi, Rodrigo January 2011 (has links)
Neste trabalho foi desenvolvida uma nova metodologia para a síntese de calcogenoacetilenos. Para isto, foram utilizados haletos de índio III como catalisadores, uma base para ativar o alcino terminal e um dicalcogeneto de diorganoila. Foram avaliados diferentes haletos de índio; a saber, InCl3, InBr3 e InI3. Diferentes bases também foram testadas, sendo que a mais efetiva na promoção da reação foi o Cs2CO3. A quantidade de catalisador também foi avaliada, sendo que a que o melhor resultado foi observado quando 10 mol % de InCl3 foi empregada. Alem de testes com catalisadores e bases, foram realizados testes com diferentes solventes, e o solvente que se mostrou mais efetivo foi DMSO. A reação está mostrada abaixo, o mecanismo da mesma será elucidado no decorrer desta dissertação. Depois de otimizadas as condições reacionais, a metodologia foi estendida a diferentes disselenetos, um dissulfeto e um ditelureto, onde a reação apresentou bons rendimentos em geral. Os rendimentos obtidos com diferentes calcogênios foi na ordem S<Se<Te, o que pode ser explicado pela força de ligação S-S ser maior que Se-Se que é maior que Te-Te. A reação também foi extendida a grupos alquílicos, que reagiram bem tanto no lado do disseleneto quanto no lado do alcino. Por fim foi proposto um mecanismo evidenciado pelos resultados obtidos nos testes realizados. Onde pode ser explicado o efeito eletrônico da reação e o efeito do solvente, onde o DMSO foi escolhido como o melhor solvente para a reação. / A new approach for the one-pot synthesis of alkynyl chalcogenides, exemplified mainly by selenides, was developed in which dual activation of diorgano dichalcogenides and terminal acetylenes is achieved by using an indium(III) catalyst. The method has advantages of broad substrate scope, simple operation, mild reaction conditions, and good yields. A plausible reaction mechanism is proposed.
54

Síntese de calcogenoacetilenos catalisada por haletos de In III

Giovenardi, Rodrigo January 2011 (has links)
Neste trabalho foi desenvolvida uma nova metodologia para a síntese de calcogenoacetilenos. Para isto, foram utilizados haletos de índio III como catalisadores, uma base para ativar o alcino terminal e um dicalcogeneto de diorganoila. Foram avaliados diferentes haletos de índio; a saber, InCl3, InBr3 e InI3. Diferentes bases também foram testadas, sendo que a mais efetiva na promoção da reação foi o Cs2CO3. A quantidade de catalisador também foi avaliada, sendo que a que o melhor resultado foi observado quando 10 mol % de InCl3 foi empregada. Alem de testes com catalisadores e bases, foram realizados testes com diferentes solventes, e o solvente que se mostrou mais efetivo foi DMSO. A reação está mostrada abaixo, o mecanismo da mesma será elucidado no decorrer desta dissertação. Depois de otimizadas as condições reacionais, a metodologia foi estendida a diferentes disselenetos, um dissulfeto e um ditelureto, onde a reação apresentou bons rendimentos em geral. Os rendimentos obtidos com diferentes calcogênios foi na ordem S<Se<Te, o que pode ser explicado pela força de ligação S-S ser maior que Se-Se que é maior que Te-Te. A reação também foi extendida a grupos alquílicos, que reagiram bem tanto no lado do disseleneto quanto no lado do alcino. Por fim foi proposto um mecanismo evidenciado pelos resultados obtidos nos testes realizados. Onde pode ser explicado o efeito eletrônico da reação e o efeito do solvente, onde o DMSO foi escolhido como o melhor solvente para a reação. / A new approach for the one-pot synthesis of alkynyl chalcogenides, exemplified mainly by selenides, was developed in which dual activation of diorgano dichalcogenides and terminal acetylenes is achieved by using an indium(III) catalyst. The method has advantages of broad substrate scope, simple operation, mild reaction conditions, and good yields. A plausible reaction mechanism is proposed.
55

Síntese e caracterização de materiais metal-orgânicos baseados em derivados tiofênicos e íons Európio (III)

ABREU NETO, Alfredo Quirino de 12 September 2016 (has links)
Submitted by Alice Araujo (alice.caraujo@ufpe.br) on 2018-06-07T22:22:56Z No. of bitstreams: 1 DISSERTAÇÃO Alfredo Quirino de Abreu Neto.pdf: 3451361 bytes, checksum: 1c47475cc17d115b34319e526e114698 (MD5) / Made available in DSpace on 2018-06-07T22:22:56Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO Alfredo Quirino de Abreu Neto.pdf: 3451361 bytes, checksum: 1c47475cc17d115b34319e526e114698 (MD5) Previous issue date: 2016-09-12 / CNPQ / Visando obter novos materiais luminescenteé que se desenvolveu o presente trabalho, onde foram sintetizados e caracterizados seis compostos metal-orgânicos luminescentes via método hidrotérmico (80°C), empregando-se 0,065 mmol doíon Eu+3 e os ligantes ácido2,5-tiofenodicarboxílico (TDC) e ácido 2-tiofeno acético (TAC) nas seguintes razões molares (TDC/TAC): 1:0 (A), 1:1 (B), 3:2 (C), 9:1 (D), 2:3 (E) e 1:9 (F). Os materiais luminescentes foram caracterizados por Espectroscopia no Infravermelho, Microscopia Eletrônica de Varredura, Difração de RaiosX de Pó, Espectroscopia por Dispersão de Energia, Análise Elementar, Análise Termogravimétrica e Espectroscopia de Luminescência. Os estudos revelaram que a presença do ligante TAC nas estruturas, provocou uma modificação na morfologia do cristal para estruturas em lamelas, em relação ao sistema com 100% TDC cuja morfologia é romboédrica. Todas as amostras apresentam-secristalinas e pela espectroscopia de emissão, exibiram as transições características do íon Eu3+. Para elucidar as estruturas do ambiente ao redor do íon Eu3+, foram realizados estudos computacionais, somente para os sistemas em que o espectro de luminescência indicava um único sítio para o íon európio(compostos A e B). Para ambos os casos o poliedro de coordenação que mais se aproximava da literatura era o “cappedsquareantiprisma”, o que possibilitou obter os diagramas dos níveis de energia, mostrando os prováveis canais para o mecanismos de transferência de energia intramolecular (TE) e retro-transferência (BT) entre o íon Eu3+ e os ligantes e vice-versa. / In order to obtain new materials with luminescent properties we have developed this work. Six metal-organic luminescent compounds (A-F)were synthesized via the hydrothermal method (80°C), using 0.065 mmol of Eu+3 and 2,5-tiofenodicarboxílico acid (TDC) and 2-thiophene acetic acid (TAC) in the molar ratios (TDC / TAC) 1:0 (A); 1: 1 (B); 3: 2 (C); 9: 1 (D); 2: 3 (E); and 1: 9 ( F). The luminescent materials were characterized by Infrared Spectroscopy, Scanning Electron Microscopy, X-ray Powder Diffraction, EnergyDispersionSpectroscopy, Elemental Analysis, Thermogravimetric Analysis and LuminescenceSpectroscopy. The studies revealed that the presence of the TAC ligand caused a change in the crystal morphology. The rhombohedral structure characteristic of the material containing exclusively the TDC ligand changed to lamella structures in the presence of TAC. All coordination materialswere crystalline and exhibited the characteristic transitions for the Eu+3 ionsin the emission spectra. For systems A and Bthe luminescence spectra indicated a single site forthe Eu+3ions.For these systems computational studies were undertaken to elucidate the structures around the Eu+3ions.Diagrams of the energy levels, showing the possible mechanisms for intramolecular energy transfer (TE) and back-transfer (BT) between the metalion and the ligands were obtained.
56

Avaliação Clínica de Restaurações de Classe III com Resinas Compostas.

Fatima Cristina de Sá 16 March 2000 (has links)
Avaliou-se clinicamente 2 resinas compostas (Z-100 e Fill Magic),quanto a: sensibilidade pós-operatória, forma anatômica, cárie secundária, integridade marginal, descoloração marginal, cor e a influência do período de observação (“baseline”, 6 meses, 1 ano e 2 anos) no desempenho desses fatores. Participaram 43 pacientes, que receberam 2 restaurações de classe III, 1 de cada resina, totalizando 86 restaurações. Fez-se a avaliação inicial das restaurações, o “baseline”, 7 dias após a sua confecção, por 2 examinadores. Cada item recebia um escore em 3 níveis: bom (0), aceitável (1) e inaceitável (2). Somente para a cárie considerava-se 2 níveis: ausente (0) e presente (1). Fotografou-se as restaurações em todos os períodos de observação. Obteve-se moldagens das restaurações de 10 pacientes, para análise e fotografias em Microscópio Eletrônico de Varredura, com aumento de 40 X. Dos 43 pacientes, 8 não retornaram, assim, analisou-se estatisticamente pelo teste exato de Fisher, 70 restaurações. No baseline, 34 restaurações com a resina composta Z-100 e 35 com a Fill Magic receberam escores zero em todas as categorias, com exceção de 1 caso com a resina Z-100 que recebeu escore 1 para o critério cor. Para esse mesmo critério, aos 6 meses, 35 restaurações com a Fill Magic e com a Z-100, 31 restaurações receberam escores zero e 4 mereceram escores 1. Em 1 ano, 31 restaurações com a Z-100 ficaram com escores zero e 4 com escores 1; 34 restaurações com Fill Magic obtiveram escores zero e 1 obteve escore 1, com relação à cor. Aos 2 anos, também com relação à cor, para 3 restaurações com Z-100 e para 1 com Fill Magic atribuíram-se escores 1; escores 0 foram aplicados a 32 das restaurações de Z-100 e a 34 das de Fill Magic. Exceto para a categoria cor, que sofreu mudanças com o passar do tempo, todas as restaurações receberam escores 0 na avaliação “baseline”, 6 meses, 1 ano e 2 anos. Nenhum escore 2 foi anotado. Não observou-se diferença estatisticamente significante entre as 2 resinas compostas, aceitando-se a hipótese de igualdade entre as mesmas. / The purpose of this study was to clinically evaluate two composite resins at 2-year period. Seventy Class III restorations were made by only one operator, 35 with Z-100 composite resin and 35 with Fill Magic. The teeth were selected based on clinical exams. Restorations included only anterior superior teeth. Following cavity preparations, under rubber dam, they were protected with calcium hydroxide and/or a glass ionomer base. Magic Adhesiv/Fill Magic (Vigodent) and Scotchbond Multipurpose Plus/Z-100 (3M) were used for adhesion to exposed dentin and enamel and restoration of the cavities. The cavities were restored in increments. Restorations were finished using multi-laminated burs, Sof-Lex discs and Enhance System. Evaluation was assessed after finishing and polishing approximately one week after placement (baseline), 6 months, 1 year and 2 years using the modified Ryge criteria for color, marginal discoloration, anatomic form, marginal integrity, secondary caries and post-operative sensitivity. There were three levels of scores for each category: good (0), acceptable (1) and unacceptable (2). Only for secondary caries there were 2 levels: absent (0) and present (1). Besides, it was investigated the occurrence of postoperative sensitivity, which was classified as the other scores were for another characteristics observed. At every evaluation, impressions from the restorations were made and they were examined by scanning electron microscopy. At baseline, there was one score “one” for category color for Z-100 composite resin; the other restorations and the other composite resin were graded to be “zero”. At 6 months recall, the restorations were assessed and there were four scores “one” for Z-100 composite resin. The restorations were evaluated at 1 year and the results were as follow: there were four scores “one” for Z-100 composite resin and one score “one” for Fill Magic composite resin with regard to color. At 2-year evaluation were observed three scores “one” for Z-100 composite resin and one score “one” for Fill Magic. Except for color category, all the restorations received score “zero” either for 6 months, 1-year and 2- year recalls. No scores “two” were noted. The results were analyzed by Fisher Exact Statistical Test. No significant differences were noted between both composite resins. In conclusion, these two composite resins demonstrated excellent clinical acceptability in all categories assessed, making them suitable for anterior restorations.
57

Franz of Anhalt-Dessau and England : the Wörlitz landscape garden and anti-Prussian politics in the late enlightenment

Umbach, Maiken January 1996 (has links)
No description available.
58

Standardy likvidity podle BASEL III a jejich dopad na vybrané banky ČR / Basel III Liquidity Standards and their Applied Impact on Selected Czech Banks

Plíva, Rostislav January 2014 (has links)
Subject of this dissertation thesis is the readiness of selected Czech banks and one cooperative lending institution to implementation of BASEL III capital requirements. Analysis is concentrated to current state of BASEL II and BASEL III in field of liquidity. For a purpose of comparison the indicator of Liquidity Coverage Ratio required by BASEL III is calculated and, when necessary, theoretically modeled. Institutions are analyzed whether they are ready and what measures should be implemented to fulfill liquidity requirements including the impact of these measures to the market and market of financial instruments.
59

Croissance sélective et caractérisation de nanostructures de matériaux III-V élaborées par épitaxie par jets moléculaires / Selective area molecular beam epitaxy and characterization of III-V nanostructures

Bucamp, Alexandre 22 November 2019 (has links)
Que ce soit pour la fabrication de transistors ultimes fonctionnant à haute fréquence et faible consommation d’énergie ou pour celle de composants quantiques exploitant le transport balistique d’électrons, l’élaboration de nanostructures de semiconducteurs III-V à faible masse effective électronique est aujourd’hui un enjeu majeur. Différentes approches existent pour atteindre des dimensions caractéristiques largement sub-100nm. Les nanostructures peuvent être définies par une approche descendante en combinant gravure sèche anisotrope et amincissement chimique digital d’une couche semiconductrice ou par une approche ascendante en élaborant directement les nanostructures désirées. Dans le deuxième cas, la croissance de nanofils catalysée par une bille métallique nanométrique a connu un engouement important ces quinze dernières années. La fabrication de composants utilisant ce procédé reste cependant très compliquée et nécessite souvent le report des nanofils sur un substrat hôte rendant extrêmement difficile la réalisation de circuits complexes. L’approche par croissance sélective dans les ouvertures d’un masque diélectrique offre au contraire des perspectives plus intéressantes. Si l’épitaxie à base d’organométalliques en phase vapeur a démontré son efficacité pour ce type de croissance, l’épitaxie par jets moléculaires peut permettre d’améliorer encore la pureté des nanostructures. C’est dans ce contexte que nous avons étudié les propriétés électriques de nanostructures III-V épitaxiées sélectivement sur substrat InP. L’utilisation d’un flux d’hydrogène atomique pendant la croissance permet d’obtenir une bonne sélectivité de croissance. Son impact sur les propriétés optiques et électriques du semiconducteur a d’abord été étudié puis l’utilisation de procédés de nanofabrication a permis l’élaboration et la caractérisation électrique de nanostructures. Des composants en InGaAs de type TLM, multi-branches ou MOSFET ont démontré la qualité des matériaux épitaxiés puisque des mobilités effectives à l’état de l’art pour ce type de matériau ont été obtenues. Grâce à l’utilisation de croissances sélectives multiples, nous avons pu élaborer des hétérostructures originales telles que des nanofils planaires à cœur InGaAs et coquille InP ou des hétérojonctions InGaAs/GaSb radiales ou axiales. Pour ces dernières, l’obtention de caractéristiques courant-tension présentant une résistance différentielle négative montre une bonne qualité d’interface, offrant des perspectives intéressantes pour la fabrication de nano-hétérojonctions tunnel. / The fabrication of nanoscale devices such as high frequency and low energy consumption transistors or quantum devices exploiting ballistic electrons transport requires the development of nanostructures with low effective mass III-V materials. Several technologies exist to reach typical dimensions well below the 100-nm range. The nanostructures can be defined by a top-down approach through a combination of anisotropic dry etching and digital chemical thinning of a semiconductor layer, or by a bottom-up approach with a direct elaboration of the nanostructures. In the second case, metal-catalyst-assisted nanowire growth has been widespread since the last fifteen years. However, the fabrication of devices based on this process is still tricky and often requires the transfer of the nanowires to a host substrate for device processing, preventing any complex circuit production. The approach by selective area growth inside dielectric mask openings exhibits a better scalability. If the organometallic vapor phase epitaxy (MOVPE) has proved its efficiency for this type of growth, molecular beam epitaxy (MBE) may further improve the nanostructure purity. Within this context, we study the electrical properties of selectively grown III-V materials on InP substrate by MBE. We demonstrate that the use of an atomic hydrogen flux during the growth ensures a good selectivity with respect to the dielectric mask and has a positive impact on the optical and electrical properties of the grown semiconductor. The electrical characterization of InGaAs nanostructures is performed thanks to the development of dedicated process such as TLM, branched nanowires or MOSFET devices. It reveals good transport properties with the state-of-the-art effective mobility for this kind of alloy. We then show that selective area epitaxy is also a valuable tool to develop original heterostructures such as in-plane InGaAs/InP core-shell nanowires with raised contacts and radial or axial InGaAs/GaSb heterojunctions. For these latter, the negative differential resistances observed on the current-voltage characteristics demonstrate a good interface quality, offering interesting possibilities for tunnel nano-heterojunction development.
60

Reclaiming the Flock: Innocent Iii, the 1215 Canon and the Role of the Sacraments in Reforming the Catholic Church

Villarreal-Thaggard, Kimberly 12 1900 (has links)
This thesis traces the changes in the sacraments of Baptism and the Eucharist from 400-1215 and posits that Innocent III’s Fourth Lateran Council solidified and clarified these sacraments from diversified practices and customs to a single Catholic orthodoxy in order to reclaim centralized papal power to the Roman Catholic Church. Tracing the history of the Catholic Church’s baptismal and Eucharistic rites encounters a number of logistical obstacles because they were not administered by means of a Western Church-prescribed ritual until the early thirteenth century, primarily because such a prescription did not exist. Even after the First Council of Nicaea where Christian doctrine was better defined, an allowable margin of license remained within Latin orthodoxy, specifically when it came to the practice and administration of the sacraments. Before the establishment of a finite canon the sacramental procedures of the Western Church relied heavily on the local bishops and monks who openly adopted their own preferential liturgies and ritual practices. This fragmentation took the power away from the Holy See in Rome and instead fostered the idea that regional practices were superior. The foundation of their varied interpretations can be traced back to a number of theologians ranging from the early second century tracts of Justin Martyr to Augustine in the late fourth century. Upon the inauguration of Pope Innocent III in 1198, however, the Church adopted a policy of zero tolerance for practices, rituals and individuals that it deemed heretical. Through a series of papal bulls that even began in the first months of Innocent’s reign, he initiated an attempt to eradicate regional inconsistencies and to create a more streamlined orthodoxy. This movement was fully realized in the year before Innocent’s death with the creation of the 1215 Canon in which Catholic Church leaders from around the world defined, explained and mandated sacramental ritual, as well as the expectations for the priests and clerics who administered them. The canon was a compilation of reformed laws for the Church of the Latin West, almost all of which can be directly traced to Innocent’s own decretals and papal bulls. This canon used Biblical references as well as Roman Church and apostolic tradition to define these rites and the role of those who administered them. The goal of Innocent’s reform was to redirect and update the canonical practices within Catholic orthodoxy, while at the same time it helped to identify and extinguish, Christian sects and princes who refused the divinely ordained and irrefutable power of the Catholic Church in Western Europe.

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