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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.
81

Furnace calculations

Brooks, John McMillen. January 1906 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1906. / Jno. M. Brooks, Jr. determined to be John McMillen Brooks from "Forty-First Annual Catalogue. School of Mines and Metallurgy, University of Missouri". The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed )
82

Optische Studien über I. Kupferammoniakomplexe, II. Gelbe und rote Salze aus p-Oxyazobenzolen

Robertson, P. W. January 1909 (has links)
Thesis (doctoral)--Universität Leipzig, 1909. / Vita. Includes bibliographical references.
83

An approximate determination of the depth of compression in copper bars during impact,

Tschudi, Erwin William, January 1900 (has links)
Thesis (Ph. D.)--Johns Hopkins University, 1925. / Reprinted from Physical review, v. 26, no. 1, July, 1925. eContent provider-neutral record in process. Description based on print version record. Biographical note.
84

The role of copper in murine lymphocyte blastogenesis in vitro

Rademacher, Thomas William. January 1979 (has links)
Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
85

Aqueous environmental chemistry of copper

Sánchez-Vázquez, Isaac, January 1971 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1971. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
86

The decomposition of the beta phase in the copper-aluminum and copper-tin systems

Toner, Daniel Frank, January 1956 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Abstracted in Dissertation abstracts, v. 16 (1956) no. 10, p. 1876-1877. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 110-111).
87

Porphyry copper related mineralization in the Terre Neuve district, Haiti, West Indies

Harnish, David Emmanuel. January 1984 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1984. / One folded map in pocket. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 71-74).
88

Etude de l’influence des impuretés dans des microalliages de cuivre sur leurs microstructures et leurs propriétés mécaniques / Study of the influence of impurities in microalloys copper on microstructure and mechanical properties

Savina, Romain 01 December 2014 (has links)
Ce travail s'inscrit dans l'activité de production de câbles électriques en cuivre par l'entreprise NEXANS. La coulée continue, située sur le site de Lens, permet d'obtenir des demiproduits se présentant sous forme de fils de cuivre de diamètre 8mm. Si à l’origine ce genre de système de production utilise du cuivre « pur », qualifié d’ETP-1 (pureté >99,99%), aussi appelé cathodes électrolytiques, afin d’obtenir du fil de cuivre, ces derniers années, la coulée continue de Lens a élargi son activité vers le recyclage en introduisant des déchets riches en cuivre sur leur système. On distingue ainsi deux grandes familles de demi-produits ; la première, classée ETP-1, obtenue à partir de cuivre « pur » (Cu-ETP-1), et la deuxième, classée ETP-A, obtenue en introduisant un certain pourcentage de cuivre issu de déchets qualifiés de propres (déchets relativement purs). Cependant, dans cette optique environnementale et économique forte, le retour d'expérience de la chaîne de production a montré ces dernières années des problèmes de fissuration à chaud lors de l'élaboration des demi-produits. Ces problèmes concernent principalement le cuivre ETP-A, donc a priori le cuivre le plus riche en impuretés. Ainsi ces travaux de thèse ont pour but d’expliquer les raisons de ce problème sur la coulée continue en identifiant le(s) facteur(s) responsable(s) et en expliquant leur rôle sur le(s) mécanisme(s) de fissuration. Afin de répondre à cette problématique, après avoir étudié l’influence de l’oxygène et du plomb sur la microstructure par l’intermédiaire des diagrammes de phases binaire Cu-O et ternaire Cu-O-Pb, nous concentrons notre étude sur l’influence de ces impuretés sur les propriétés mécaniques du cuivre. Des essais de traction in situ au Microscope Electronique à Balayage ont été réalisés sur des échantillons à différentes compositions chimiques et à différentes températures afin d’observer leur évolution microstructurale au cours de la déformation tout en reproduisant le phénomène de fissuration observé sur le système de production. Au préalable de chaque essai de traction, des analyses EBSD sont effectuées afin de pouvoir déterminer la localisation de l’amorçage de fissures et d’acquérir de nombreux paramètres pouvant jouer un rôle sur les propriétés mécaniques (texture, facteur de Schmid…). Ces nombreux essais montrent des différences notables de propriétés mécaniques et de mécanismes de fissuration en fonction de nombreux paramètres que nous identifions (température, état de porosité, désorientation associée aux joints de grains, état de précipitation…). / This study takes place in the context of electric wires production using waste copper. Oxygen and sometimes lead are present in small amount in these products. We decide to study their influence on the microstructure and mechanical properties. After studying the influence of oxygen and lead on the microstructure using the binary phase diagram Cu-O and the ternary phase diagram Cu-O-Pb, we focused our work on the influence of these impurities on mechanical properties. In-situ tensile tests have been carried out on samples at different chemical compositions inside the SEM chamber to observe the evolution of microstructure during déformation. Before each deformation test, EBSD analysis has been achieved to make the identification of cracks localization easier and acquire several parameters that can have an influence on mechanical properties (texture, Schmid factor...). These tests show important differences on mechanical properties and craking mechanism according to various factors that we indentify (temperature, porosity, grain boundary misorientation, precipitation....).
89

Influence of oxygen on the interfacial reaction between sapphire and copper.

Misra, Surya Kumar January 1964 (has links)
The influence of oxygen on the wetting of sapphire (α-Al₂O₃) by liquid copper was investigated using the sessile drop technique in vacuum at 1230°C. For additions to copper of cupric oxide, varying from 1 – 72% of the copper weight, chemical reaction at the liquid-solid interface resulted in spreading of the liquid and a rapid decrease of the contact angle to a steady state value. A direct relationship between the fourth power of the basal radius of the molten drop and the oxygen present was observed. The product of the interfacial reaction was found to be CuAlO₂. Phase diagrams of the systems CuO-Al₂O₃ and Cu₂O-Al₂O₃ were determined experimentally using X-ray diffraction techniques for identification of the phases. The aluminates, Cu(AlO₂)₂ and-CuAlO₂ were identified and their ranges of stability in air established. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
90

Growth and deformation of copper whiskers

Shetty, Mangalore Nagappa January 1964 (has links)
Copper whiskers were grown by the hydrogen reduction of the halide vapours. The substrate and the whiskers were examined for growth morphologies. Whiskers of (100), (110) and (111) orientations in the diameter range 30-400μ were tested in tension. Differences in the work hardening characteristics of (111) and (100) whiskers were discussed in terms of the different kinds of jogs formed in the two orientations. Analysis of the diameter dependence of the yield stress resulted in a 1/d relation based on the assumption of surface nucleation of dislocations. Temperature and strain rate change experiments were made on (110) whiskers. Activation distance and activation energies were used to determine a rate controlling mechanism. At low temperatures, cross slip and intersection processes were indistinguishable, while at higher temperatures, cross slip is rate controlling. From the calculated activation distance and for a given rate controlling dislocation mechanism, stacking fault energies were estimated for copper and other FCC metals. A twinning model was proposed based on the idea of failure by recombination of a Lomer-Cottrell barrier. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

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