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- Aluminum oxide -- Thermal properties<br />Thermal stresses (1)
- Chromium -- Spectra<br />Lattice paths<br />Ligands (Biochemistry)<br />Magnesium oxide (1)
- Chromium<br />Roasting (Metallurgy)<br />Sintering (1)
- Metal ions<br />Metallurgy -- Ion exchange process<br />Micelles<br />Organosulfur compounds (1)
- Nickel<br />Radioactive tracers in metallurgy<br />Surface energy (1)
Articles 1 - 5 of 5
Full-Text Articles in Engineering
Decomposition Of Cr(Oh)₃ To Form Active Cr₂C₃, Timothy A. Clancy
Decomposition Of Cr(Oh)₃ To Form Active Cr₂C₃, Timothy A. Clancy
Doctoral Dissertations
"This study was concerned with the sinterability of Cr₂C₃ powders produced by the calcination of a Cr(OH)₃ gel. The decomposition of the gel was investigated by thermogravimetric analysis, X-ray analysis and microscopic examination. Comparison was made between the size of crystallites as determined by X-ray line broadening and the size of aggregated particles as determined by independent means. These lineal measurements were compared to surface area measurements on the calcined powders. The degree of sinterability was judged from the density measurements on Cr₂C₃ pellets fired under air, oxygen and nitrogen atmospheres. Energies of activation of 25 and 20 kilocalories per …
Effect Of Micelles On Flotation Of Metal Ions, Uriel Michael Oko
Effect Of Micelles On Flotation Of Metal Ions, Uriel Michael Oko
Doctoral Dissertations
"A study of the anionic surfactant, sodium dodecyl sulfate (SDS), and the dependency of the adsorption of divalent metal counterions such as copper and zinc at the air-water interface on its concentration in the solution, was undertaken in order to better understand the process of ion flotation. The study is divided into two broad categories, the first of which consists of the evaluation of the extent of aggregation of the surfactant molecules into micelles, and the effect of the divalent metal counterion concentration on this aggregation and on the critical concentration at which micelles start forming (cmc). This was accomplished …
Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe
Surface Self-Diffusion On Nickel (111) By Radioactive Tracers, James Ronald Wolfe
Doctoral Dissertations
"Surface self-diffusion coefficients have been measured by a radioactive tracer method over the temperature range 614⁰ to 840⁰C on nickel (111) surfaces characterized by LEED. Previously unrecognized tracer evaporation during surface diffusion resulted in restricted spreading of the tracer at higher temperatures. A theoretical treatment of the tracer evaporation phenomenon is presented and subsequently used in the analysis of the data. The temperature dependence of the surface self-diffusion coefficient (Ds) for nickel (111) can be represented, over the experimental temperature range, by a single Arrhenius type relationship...Arguments are presented to justify an adatom surface diffusion mechanism which is …
The Damage Assessment Of Thermally Shocked High Density, High Purity Aluminum Oxide, John H. Ainsworth
The Damage Assessment Of Thermally Shocked High Density, High Purity Aluminum Oxide, John H. Ainsworth
Doctoral Dissertations
"The traditional approach to thermal shock testing in brittle materials has been to determine the temperature difference required to nucleate cracks in these materials. Recent work has indicated that the degree of damage after crack nucleation should be an additional consideration. The degree of damage resulting from cooling thermal shocks has been the primary consideration of the present work. Test specimens of two geometries: long, solid rods and short, solid cylinders were quenched from selected temperatures into ice water. The degree of damage was determined through strength measurements and sonic damping analysis. Initial damage occurred at a temperature difference above …
Optical Reflectance Spectra Of Chromium (Iii) In Mgo-Ss, Thomas Spencer Montgomery
Optical Reflectance Spectra Of Chromium (Iii) In Mgo-Ss, Thomas Spencer Montgomery
Doctoral Dissertations
"The valence state and coordination site of the transition-metal ion, chromium, was investigated in a MgO host lattice. The chromium ion incorporated into poly-crystalline MgO by quenching from elevated temperatures allowed investigation of a single crystalline phase, MgO-solid solution (ss). The chromium ion was confirmed to occur in the trivalent state and to occupy octahedral cation sites in the MgO lattice by the use of optical reflectance spectroscopy. The effect of the concentration of the chromium ion on the crystal field splitting energy, 10 Dq, permitted analysis over a range of Dq/B values. In conjunction, MgO-ss lattice parameters examined as …