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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.
21

Analysis and metallurgical treatment of copper ores from Ajo Basin, Arizona

Chamberlain, Harry C. January 1905 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1905. / Pages misnumbered by author. Leaf numbers 6 and 18 omitted from text. H. C. Chamberlain determined to be Harry C. Chamberlain from "1874-1999 MSM-UMR Alumni Directory". The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed November 24, 2008)
22

Physiological indicators of waterborne copper toxicity in freshwater fish /

Taylor, Lisa N. McDonald, D. G. January 2002 (has links)
Thesis (Ph.D.)--McMaster University, 2003. / Supervisor: D.G. McDonald. Includes bibliographical references (leaves 213-224). Also available via World Wide Web.
23

STABILIZATION OF COPPER(I) WITH ORGANIC LIGANDS FOR TRACE LEVEL ANALYSIS IN AQUEOUS SOLUTIONS (KINETICS, CORROSION, CYANIDE, DETERMINATION).

SCOTT, NELSON. January 1984 (has links)
The dissolution of copper metal in the presence of copper(II) ions and allyl alcohol in aqueous solution is found to be pseudo-first order with respect to both copper(II) ions and allyl alcohol. The reaction is inhibited by acid. The rate determining step is not the formation of copper(I) but the transfer of electrons from the surface of copper metal to the copper(II) ions in solution. The reaction rate has been monitored spectrophotometrically by complexing the copper(I) formed with 2,9-dimethylphenanthroline (neocuproin) and measuring the absorbance of the solution at the wavelength of maximum absorption of the complex, 450 nm. Other factors that affect the reaction are the presence of anions, the solvent composition, the nature of the unsaturated ligand used to stabilize the copper(I) and the rate of stirring. The reduction of copper(II)-neocuproin by allylamine and allyl alcohol has been studied in basic solution. A method has been developed for the rapid, sensitive determination of CN⁻ based on a spectrophotometric technique using copper(I)-neocuproin as a reagent. SCN⁻ does not interfere but S²⁻ appears to be a very powerful source of interference. By appropriate choice of the concentration of copper(I)-neocuproin reagent the range of response can be adjusted to be in the range 1-10 ppm. The theoretical detection limit of the method is as low as 19 ppb at the 95% confidence limit and the precision, measured as the relative standard deviation, is better than 1.5%. The disturbance of the equilibrium between the bis ligand and mono ligand complexes of copper(I) appears to be the reason for the observed decrease in absorbance on the addition of cyanide to a solution of copper(II)-neocuproin. The problems associated with using the commercially available ion selective electrode for cupric determination have been highlighted. The possibility of developing a PVC matrix membrane electrode for the determination of CN⁻ has been explored. The main difficulty is the instability of the copper(I)-neocuproin complex at pH values as high as 11 that are required to stabilize CN⁻.
24

Evaluation of the first-order ternary interaction parameters for bismuth in molten copper using a novel distribution technique

Jiang, Xin Hua, 1963- January 1987 (has links)
The first order ternary interaction parameters of bismuth in molten copper containing either iron, arsenic or antimony have been evaluated using a pseudo equilibrium process at temperatures between 1398 K and 1473 K. The isopiestic distribution technique developed in this investigation yielded the following results: εFeBi=[(1.11x10⁶)/T]- 754 εAsBi=[(4.4x10⁴)/T]-24 εSbBi=-11 These results, coupled with other activity data, have been used to calculate the isoactivity curves for each constituent in the copper rich corner of each ternary system. The basis for the ternary interactions associated with εFeBi, εAsBi and εSbBi are also discussed.
25

Analytical determination of copper speciation in Oregon highway runoff /

Sprick, Matthew S. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 76-82). Also available on the World Wide Web.
26

A study of copper losses in slags

Phillips, Harry Ashwill January 1928 (has links)
No description available.
27

The chemical and mineralogical forms of copper in converter slag

Boyer, Walton Tully January 1927 (has links)
No description available.
28

The recovery of copper from solutions obtained by the dissolution of copper sulfide minerals at elevated temperatures and pressures

Groves, R. D. (Rees D.), 1920- January 1960 (has links)
No description available.
29

The dissolution of copper from mixed copper ores at elevated temperatures and pressures

Hanson, George Robert, 1930- January 1957 (has links)
No description available.
30

Methods for the decomposition of copper ferrite

Butler, Gurdon Montague, 1913- January 1934 (has links)
No description available.

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