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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.
261

Creep behavior in stoichiometric NiAl

Kanne, William Rudolph, January 1968 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
262

Contribution à l'étude de la réduction par l'hydrogène des solutions solides oxyde de nickel _ oxyde cuivrique.

Grange, Paul, January 1900 (has links)
Thèse--Sc. phys.--Lyon, 1970. N°: 702. / Bibliogr. p. 70-73.
263

Usure et frottement sec de superalliages.

Papa, Emmanuel, January 1900 (has links)
Th. doct.-ing.--Sci. des matér.--Toulouse--I.N.P., 1984. N°: 301.
264

Étude des lacunes et de leur interaction avec le carbone et l'oxygène dans les alliages fer-nickel de structure c.f.c., par la méthode de l'anisotropie magnétique induite.

Caplain, Armelle, January 1900 (has links)
Th.--Sci. phys.--Grenoble 1, 1978. N°: 55.
265

EFFECT OF PRESSURE ON THE MAGNETIC PROPERTIES OF NICKEL AND NICKEL ALLOYS

Michigan, Edmond George, 1929- January 1966 (has links)
No description available.
266

Development of nickel-selective molecularly imprinted polymers

Tshikhudo, Tshinyadzo Robert 25 July 2013 (has links)
A series of eight novel bidentate ligands, designed for use in the construction of nickel-selective molecularly imprinted polymers (MIP's), have been prepared. The synthetic pathway was established by retrosynthetic analysis of the target molecules to the readily available precursors, pyridine-2-carbaldehyde (or 6-methylpyridine-2-carbaldehyde) and ethyl bromoacetate. The ligands were designed to contain an allyl group for co-polymerisation and amine and pyridyl nitrogen donors, located to permit the formation of 5-membered nickel chelates. The eight novel ligands and their respective precursors were characterized by elemental (high-resolution MS) and spectroscopic (IR and ¹H and ¹³C NMR) analysis. High resolution electron-impact mass spectrometry has also been used, together with B/E linked scan data, to explore the fragmentation patterns of selected ligands. The various nickel(ll) complexes were analyzed using spectroscopic techniques and, in some cases, elemental analysis; computer modelling has also been used to explore conformational effects and complex stability. Numerous MIP's, containing nickel(II) complexes of the bidentate ligands, have been prepared, using ethylene glycol dimethylacrylate (EGDMA) as the cross-linker, azobis(isobutyronitrile) (AlBN) as the polymerization initiator and MeOH as the porogenic solvent. The template nickel(II) ions were leached out with conc. HCI, and the nickel(II) selectivity [in the presence of Fe(Ill)] of the nickel-imprinted polymers was examined by ICP-MS analysis. The ICP-MS data indicate that the MIP's examined exhibit extremely high selectivity for nickel over iron. / KMBT_363 / Adobe Acrobat 9.54 Paper Capture Plug-in
267

The functionalization of white phosphorus towards metal phosphide nanoparticles and organophosphines / Fonctionnalisation du phosphore blanc pour la synthèse de nanoparticules de phosphures métalliques et d'organophosphines

Bhattacharyya, Koyel 02 February 2017 (has links)
Ce manuscrit présente une synthèse originale de nanoparticules de nickel(0). L'utilisation d'un précurseur de dioléylamide de nickel(II) conduit à un procédé versatile, robuste, et sans eau pour la production de particules ajustables en taille entre 4 et 11 nm de diamètre. Cette méthode a été étendue pour former de petites nanoparticules de fer(0) et de cobalt(0). Ces particules ont été examinées en ce qui concerne l'activité catalytique, y compris l'hydrosilylation d'un alcène terminal, l'hydrogénation sélective du phénylacétylène en styrène, et la réduction sous-stoechiométrique de l'azote en tris(triméthylsilyl)amine. Le phosphore blanc (P4) a été réagi stoechiométriquement avec les nanoparticules métalliques pour former les nanoparticules de phosphure métallique correspondantes. Le phosphore blanc a été alternativement fonctionnalisé en utilisant un superhydrure (LiBEt3H) pour former une espèce phosphanide stabilisée au borane, LiPH2(BEt3)2. Cette espèce a été utilisée pour synthétiser diverses phosphines, y compris la phosphine, la tris(triméthylsilyl)phosphine, et les triaroylphosphines. Les adduits labiles de triéthylborane ont été remplacés par BH3, ce qui a donné lieu à la formation de LiPH2(BH3)2, qui peut avoir des applications dans la formation de polymères P-B. / This manuscript presents an original synthesis of nickel(0) nanoparticles. The use of a nickel(II) dioleylamide precursor results in a versatile, robust, water-free method for the production of size-tunable particles between 4 - 11 nm in diameter. This method was extended to form small iron(0) and cobalt(0) nanoparticles. These particles were examined for catalytic activity, including the hydrosilylation of a terminal alkene, the selective hydrogenation of phenylacetylene to styrene, and the substoichiometric reduction of nitrogen to tris(trimethylsilyl)amine. White phosphorus (P4) was stoichiometrically reacted with the metal(0) nanoparticles to form the corresponding metal phosphide nanoparticles. White phosphorus was alternatively functionalized using superhydride (LiBEt3H) to form a borane-stabilized phosphanide species, LiPH2(BEt3)2. This species was used to synthesize various phosphines, including phosphine, tris(trimethylsilyl)phosphine, and triaroylphosphines. The labile triethylborane adducts were replaced by BH3, resulting in the formation of LiPH2(BH3)2, which may have applications in the formation of P-B polymers.
268

Valorisation énergétique de CO₂ via la méthanation par voie catalytique / Energy recovery of CO₂ through methanation process by catalytically

Elia, Nathalie 22 March 2019 (has links)
Cette étude concerne la valorisation du dioxyde de carbone par le procédé de méthanation. Elle vise à mettre au point des catalyseurs efficaces pour cette réaction. L'espèce active est le nickel métallique. Différents supports ont été étudiés tels que SiO₂, Al₂O₃, MgO, Y₂O₃ et CeO₂. Ces catalyseurs ont été préparés par la méthode d'imprégnation à sec. Dans un premier temps, les différents catalyseurs ont été caractérisés par différentes techniques physico-chimiques dont la Diffraction des Rayons X (DRX), la Réduction en Température Programmée (RTP-H₂), la Désorption en Température Programmée (DTP-CO₂), l'Adsorption d'Azote (méthode BET) et la Chimisorption d'Hydrogène. Dans un deuxième temps, les différents catalyseurs ainsi préparés ont été testés dans la réaction de méthanation du CO₂. Le catalyseur Ni/CeO₂ présente les meilleures performances catalytiques, parmi les systèmes étudiés. L'ajout du ruthénium améliore l'activité catalytique et la stabilité des catalyseurs. Le catalyseur Ru(0,5%)-Ni(5%)/CeO₂ est le plus performant, il présente une bonne activité catalytique et une bonne stabilité même pour une pression de 10 bar. Ceci le rend plus avantageux pour une application industrielle. / This study concerns the valorization of carbon dioxide by the methanation process. It aims to develop effectiv catalysts for this reaction. The active species is metallic nickel. Different supports have been studied such as SiO₂, Al₂O₃, MgO, Y₂O₃ and CeO₂. These catalysts were prepared by the dry impregnation method. Initially, the different catalysts were characterized by different physicochemical techniques including X-ray Diffraction (XRD), Temperature Programmed Reduction (TPR-H₂), Temperature Programmed Desorption (TPD-CO₂), nitrogen adsorption (BET method) and hydrogen chemisorption. In a second step, the various catalysts thus prepared were tested in the CO₂ methanation reaction. The Ni/CeO₂ catalysts has the best catalytic performance, among the systems studied. The addition of ruthenium improves the catalytic activity and the stability of the catalysts. The catalyst Ru(0.5%)-Ni(5%)/CeO₂ is the most efficient, it has good catalytic activity and good stability even as a pressure of 10 bar. This makes it advantageous for an industrial application.
269

Nickel (II) phthalocyanine-multi-walled carbon nanotube hybrids as supercapacitors

Chidembo, Alfred Tawirirana 13 August 2010 (has links)
The thesis examines for the first time the supercapacitive properties of three different nickel (II) phthalocyanine complexes, nickel (II) tetraamino phthalocyanine (NiTAPc), nickel (II) phthalocyanine and nickel (II) tetra tert-butylphthalocyanine as a) nanocomposites with multiwalled carbon nanotubes and as (b) an electropolymer supported on multiwalled carbon nanotube platform (MWCNT-polyNiTAPc). The supercapacitive properties of nickel (II) tetraaminophthalocyanine (NiTAPc)/multi-walled carbon nanotube (MWCNT) nanocomposite films have been found to possess a maximum specific capacitance of 981 F g-1 (200 mF cm-2), a maximum power density of 700 Wkg -1, a maximum specific energy of 134 Wh kg-1 and excellent stability of over 1500 chargedischarge continuous cycling. When compared to MWCNTs modified with unsubstituted nickel (II) phthalocyanine (MWCNT-NiPc) or nickel (II) tetra tert-butylphthalocyanine (MWCNT-tBuNiPc), MWCNT-NiTAPc exhibited superior supercapacitive behaviour, possibly due to the influence of nitrogen-containing groups on the phthalocyanine. The MWCNTpolyNiTAPc electrode had a maximum (112 mF cm-2) capacitance which was higher than that observed for MWCNT-polyNi(OH)TAPc (84.9 mFcm-2) but lower that of the MWCNT-NiTAPc (200 mF cm-2). Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Chemistry / unrestricted
270

Binding study of nickel complex to protein by equilibrium dialysis

Zhou, Li 01 January 1998 (has links)
A pyridine-containing Schiff base complex, 2, 12-dimethyl-3,7, 11 ,17- tetraazabicyclo( 11.3 .1 )-heptadeca-1 ( 17),2, 11 ,13, 15-pentaene, was chosen as the complex in this study based on previous studies that showed it to be the most active complex among a series of square planar nickel complexes in promoting DNA oxidation. This complex was synthesized and its structure was proven by electrospray mass spectroscopy, H-NMR, and elemental analysis. The H-NMR data also demonstrated that this complex has two vacant coordination sites in the distorted octahedral form in aqueous solution. Histone and bovine serum albumin which are typical proteins in eukaryote animals were chosen as the target materials when I studied whether this nickel complex could bind to proteins in the body. Nickel complex was labeled with Ni63 during the dialysis, and counted by a liquid scintillation counter.

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