Chemical composition cobalt oxide

Higher concentrations of nickel and cobalt in the lower, tightly-adherent layer are the main difference in the chemical compositions between the layers. The comparatively high cobalt concentrations are assumed to result from incorporation of dissolved cobalt from the coolant into the indigenous film and not to originate in the underlying base metal. As was observed in PWR oxide layers (see Section 4.3.4.4.), the crystalline structure of the tightly-adherent layer is able to incorporate cobalt more readily than the structure of the loosely-adherent layer. 

The materials currently used in the production of medical devices include stainless steels, cobalt-base alloys, titanium-base alloys, platinum-base alloys, and nickel-titanium alloys. Steels were the first modern metallic alloys to be used in orthopedics and initial problems with corrosion were overcome by modifying the composition of the steel with the addition of carbon, chromium, and molybdenum. Carbon was added at low concentrations (ca. 0.03-0.08%) to initiate carbide formation, while the addition of chromium (17-19%) facilitated the formation of a stable surface oxide layer and the presence of molybdenum (2.0-3.0%) was found to control corrosion. The compositions of stainless steels used can vary widely. Table V shows the limits for the chemical compositions of three different alloys containing eleven different elements together with the mechanical properties for the samples after annealing and cold working. 

Dittmar, A. Kosslick, H. Muller, J.P. Pohl, M.M. (2004). Characterization of Cobalt Oxide Supported on Titania Prepared by Microwave Plasma Enhanced Chemical Vapor Deposition. Surf. Coat Technol, Vol. 182 pp. 35-42 Doblhofer, K. Diirr, W. (1980). Polymer-Metal Composite Thin Films on Electrodes. J. 

The chemical oxidation of cis- or iranx-stilbene was also investigated (Vinogradov et al. 1976). The oxidant was cobalt or manganese acetate and, in separate experiments, thallium trifluoroac-etate. Acetic or triflnoroacetic acid was used as a solvent. The results of such chemical oxidation were considered from the geometrical standpoint of the recovered (nonreacted) part of the initial substrate and stereoisomeric composition of the products obtained. This allowed the desirable comparison of electrochemical and chemical reactions to be made. 

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