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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.
71

Fabrication and characterization of active and stable Ti/Si/BDD anodes for electro-oxidation /

Tian, Yuan. January 2004 (has links)
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 89-99). Also available in electronic version. Access restricted to campus users.
72

The electrolytic oxidation of organic compounds in concentrated aqueous salt solutions ...

Heard, Joseph Ruffin, January 1934 (has links)
Thesis (Ph. D.)--Columbia University, 1934. / Vita.
73

Oxidation and reduction of aldehydes from the standpoint of electromotive force measurements,

Arenson, Saul Bryan, January 1924 (has links)
Thesis (PH. D.)--University of Nebraska. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 3-4.
74

Synthesis of carbon nanotubes on metallic grids for applications in electrochemical capacitors

Nasuhoglu, Deniz. January 2007 (has links)
No description available.
75

The effect of nitroalkanes on the electrolytic oxidation of tertiary butyl amine and tertiary amyl amine

Bergen, Karl Lloyd 01 August 1975 (has links)
The electrolyses of tert.-butyl and tert.-amyl amines were run with a voltage of approximately 3v., as measured across the cell, with and without the presence of 1-2% nitro-tert.-alkane. A graphite anode was used; the supporting electrolyte was NaClO4; the solvent was the reacting amine(s) with 10-20% water to solubilize the NaClO4. The products were azo compounds, azoxy compounds, 1,3-disubstituted ureas and traces of nitroso compounds. In the case of tert.-butyl amine di-tert.-butyl carbodiimide was also shown to be a product. The presence of nitro compounds increased the yields of azoxy and nitroso compounds and decreased the yields of azo compounds. The nitro compounds were consumed during the electrolyses and the fate of the alkyl groups was to become bonded to the nitrogen atom bonded to oxygen in an azoxy product. These results were interpreted in terms of a nitrene intermediate.
76

Electrochemistry of metalloporphyrins and their catalytic reduction of oxygen at carbon electrodes /

Su, Yuhlong Oliver January 1985 (has links)
No description available.
77

Thin-film trench capacitors for silicon and organic packages

Wang, Yushu 29 August 2011 (has links)
The continuous trend towards mega-functional, high-performance and ultra-miniaturized system has been driving the need for advances in novel materials with superior properties leading to thin components, high-density interconnect substrates and interconnections. Power supply and management is becoming a critical bottleneck for the advances in such mega-functional systems because power components do not scale down with the rest of the system resulting in bulky and stand-alone power modules. Amongst the power components, thin film capacitors are considered the most challenging to integrate because of several manufacturability concerns. The challenges are related to process compatibility of high permittivity dielectrics with substrates and high surface area electrodes, yield, leakage and losses. This thesis focuses on novel thin film capacitor technologies that address some of these critical challenges. / Thesis advisor has approved the addition of errata to this item. The abstract text in the metadata record has been modified to match the document text.
78

Determinação de impurezas em cobre eletrolítico por espectrometria de massas com plasma indutivamente acoplado

Barbour, Reinaldo January 2011 (has links)
102f. / Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2013-03-27T17:17:03Z No. of bitstreams: 1 Tese doutorado final Reinaldo Barbour.pdf: 1224301 bytes, checksum: b37e38d9ef21943dba24e8f3638efbcd (MD5) / Approved for entry into archive by Ana Hilda Fonseca(anahilda@ufba.br) on 2013-04-19T13:16:36Z (GMT) No. of bitstreams: 1 Tese doutorado final Reinaldo Barbour.pdf: 1224301 bytes, checksum: b37e38d9ef21943dba24e8f3638efbcd (MD5) / Made available in DSpace on 2013-04-19T13:16:36Z (GMT). No. of bitstreams: 1 Tese doutorado final Reinaldo Barbour.pdf: 1224301 bytes, checksum: b37e38d9ef21943dba24e8f3638efbcd (MD5) Previous issue date: 2011 / CAPES / A determinação de impurezas em cobre eletrolítico, na faixa de μg g-1 e sub μg g-1, é muito importante para caracterizar o cobre de alta pureza (99,99%). As suas propriedades físicas e químicas como maleabilidade, condutividade térmica e elétrica são fundamentais nas aplicações industriais nos setores de eletricidade e eletrônica. Metais e ametais como Ag, As, Bi, Co, Cr, Fe, Mn, Ni, Pb, Sb, Se, Sn,Te e Zn modificam estas propriedades deteriorando sua maleabilidade e condutividade. A espectrometria de massas com plasma indutivamente acoplado (ICP-MS) tem sido muito empregada para a determinação elementar, em amostras industriais, devido às suas características, principalmente as relacionadas com a capacidade multielementar, a rapidez e a alta sensibilidade. As principais desvantagens da técnica são as interferências isobáricas e poliatômicas, além daquelas relacionadas à matriz. Este trabalho teve por objetivo estabelecer um procedimento analítico validado para a determinação de elementos contaminantes por ICP-MS em amostras de cobre eletrolítico, de forma a garantir os limites de quantificação exigidos para a certificação do cobre. O equipamento empregado foi operado nos modos padrão e CCT (célula de colisão que utiliza 1,0% (v/v) NH3 em He balanço) com comutação automática. As amostras e materiais de referência certificados foram digeridos, em triplicata, empregando bloco aquecedor, seguindo o procedimento: 10  1 mg de amostra com 2 mL de HNO3 1:1 (v/v) à 70ºC. A diluição final foi de 5000x, o que contribui para minimização dos efeitos de matriz provenientes da alta concentração dos íons de cobre (~200 ug g-1). Os isótopos selecionados no modo normal de operação do equipamento foram: 55Mn, 59Co, 60Ni, 68Zn, 75As, 107Ag, 118Sn, 121Sb, 128Te, 208Pb e 209Bi. Para o modo com célula de colisão, os isótopos foram: 52Cr, 56Fe, 57Fe, 77Se e 78Se. A faixa linear estudada foi de 0,01 a 2 ng g-1. Os limites de quantificação encontrados (μg g-1 no cobre) foram: Ag (0,05), As (0,2), Bi (0,05), Co (0,1), Cr (0,2), Fe (0,5), Mn (0,2), Ni (0,2), Pb (0,1), Sb (0,2), Se (0,2), Sn (0,2),Te (0,1) e Zn (0,5). A exatidão foi avaliada pela analise dos seguintes materiais de referência certificados: BAM-M381, BAM-M382, BAM-M383, BAM-M384 (Pure Copper, BAM; Federal Institute for Materials Research and Testing) e NIST 495, NIST 496, NIST 457 (National Institute of Standards and Technology) sendo que a maioria das recuperações obtidas foram entre 80 e 120% e os %RSD menores que 10% (Se < 20%). O efeito de matriz foi avaliado através das técnicas de calibração: calibração externa com padrões internos, calibração com adição de analito e calibração com uso dos CRMs e não houve diferença significativa dos resultados. A técnica DC-ARC OES foi empregada para comparação dos resultados. A avaliação dos resultados das amostras reais de bobinas foi feita por meio de ensaios interlaboratoriais e do critério z score. Por este critério, a maioria dos resultados obtidos foram considerados excelentes. Pode-se concluir que o método proposto, empregando ICP-MS, é adequado para determinação multielementar / Salvador
79

SURFACE CHARACTERIZATION OF TITANIUM AND TITANIUM DEUTERIDE GAS-PHASE AND SOLUTION-PHASE OXIDATION PROCESSES (SURFACE ANALYSIS, ANGER ELECTRON SPECTROSCOPY).

Burrell, Michael Craig January 1984 (has links)
The reactions of atomically clean, titanium film surfaces with oxygen, deuterium, and water have been investigated. Auger Electron Spectroscopy was utilized to monitor the formation 9f a surface oxide in the case of oxygen exposure, and to characterize the deuteride which formed upon deuterium absorption, and its subsequent oxidation. Quantification of surface oxide stoichiometries was facilitated by novel data acquisition and treatment schemes. The quartz crystal microbalance was used to measure the mass of adsorbed oxygen or deuterium with submonolayer sensitivity. Electron energy loss spectroscopy was sensitive to the presence of Ti⁺³ in the surface oxide. The initial oxidation of the titanium surface was characterized by the dissociative adsorption of three mono1ayers of oxygen atoms at a constant rate. The oxide formed during this reaction stage was a Ti₂0₃/Ti0₂ mixture with a total thickness of 13 A. The rate of oxygen adsorption then decreased such that oxide growth was logarithmic with time. When the oxide had attained a total thickness of 20 A, the initial suboxide was converted to Ti0₂, and subsequent oxide formed was purely Ti0₂. Oxide growth occurred by oxygen anion migration under the influence of an electrostatic field, set up across the oxide layer by electron transfer from the metal to adsorbed oxygen species. The pressure dependence of the oxide growth rate and terminal thickness suggested a constant field growth mechanism. Clean titanium films reacted with deuterium to form a bulk deuteride TiDₓ (x<2). The oxide layer which resulted from oxygen exposure was characterized by the above techniques. Oxide layers greater than 20 A completely inhibited deuterium absorption by prohibiting 02 dissociation, but did not act as a diffusional barrier when additional dissociation sites were provided. Iron adlayers were found to accelerate the D₂ absorption reaction. Removal of the titanium films from the vacuum chamber to an isolable electrochemical reaction chamber, without exposure to the atmosphere, allowed a determination of the effect of the various gas/solid reactions on the subsequent electrochemical oxidation processes.
80

THIN LAYER PHOTOELECTROCHEMISTRY OF DYE MODIFIED ELECTRODES.

Thacker, Brad Robert. January 1983 (has links)
No description available.

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