Carbon in metal

Chart 1. Different coordination modes of carbonate in metal carbonates. 

The different types of coordination modes of carbonate in metal carbonato complexes offer challenges to investigate intimate mechanisms of their formation. The study of the kinetics and mechanisms of the formation and decomposition of such complexes, therefore, continue to be an interesting area of activity as it has a direct bearing on... 

Similar methods are applied by Kuczynski and Landauer (K7) to the diffusion of carbon in metallic carbides, in which a metal-carbon... 

Quaternary carbon nuclei e.g. CO carbons in metal carbonyls) display particularly large spin-lattice relaxation times, so that relaxation reagents such as chromium acetyl-ace tonate must be added to the sample solution in order to obtain sufficient signal noise within reasonable accumulation times. 

The kinetics of the C—C02 reaction have been analysed in a number of recent publications.48-50 In one of these, the oxidation of carbon in metallic melts (Fe-C and Ni-C) by exposure to a C02-N2 gas stream has been monitored.50 The reaction can best be rationalized by a combination of the two consecutive steps (2) and (3), in which the C02 is reduced at the metal surface to give CO and adsorbed oxygen, (0)m, which then reacts with soluble carbon, (C)m, to form CO.50... 

In I, the electron pair base character of CO can arise from donation of the lone pair on carbon, while its acid character can arise from utilization of an empty p-orbital on carbon. In MO terms the ir-acidity of CO originates from the interaction of filled orbitals of appropriate symmetry with empty, antibonding orbitals, (iTy ) or (.if ), of CO. Despite lone pairs located formally at both the carbon and the oxygen ends, carbon monoxide behaves as a base only at carbon in metal carbonyls . However, spectroscopic evidence points to the existence of linkage isomerism for carbon monoxide in Au(CO)(OC) obtained by cocondensation of gold vapors and CO at approximately lOK. ... 

Emission spectroscopy with arc and spark excitation has been used since the 1930s for many industrial analyses. In metaUurgy, for example, the presence in iron and steel of the elements nickel, chromium, sihcon, manganese, molybdenum, copper, aluminum, arsenic, tin, cobalt, vanadium, lead, titanium, phosphoms, and bismuth have been determined on a routine basis. Modem instruments can also measure oxygen, nitrogen, and carbon in metals, which used to require separate measurements with dedicated high-temperature... 

In many processes, carbon is present as the primary or secondary oxidant. Where carbon is the primary oxidant, the principal reaction is that of carburization or the dissolution of carbon into the metal matrix. The solubility of carbon in metals varies widely, being very low in Ni, Cu, Co, and ferritic iron but quite substantial in austenitic iron. Carburization of alloys, principally steels, is a common treatment for developing a hard and strong surface on components that are exposed to contact wear during service. The theory and techniques for this are clarified in the literature. ... 

Fro] Fromm, E., Hoerz, G., Hydrogen, Nitrogen, Oxygen, and Carbon in Metals , Int. Mater. Rev., (5/6), 269-312 (1989) (Kinetics, Phase Diagram, Review, Thermodyn., 255)... 

Chahine, R.. Benard, P (2001) Assessment of Hydrogen Storage on Different Carbons, in Metal Hydrides and Carbon for Hydrogen Storage Richard Chahine (Canada). 

Some (Lavoisier, Bayen, de la Place, Monge, Meusnier, etc.), whose number increases daily, deny that phlogiston is contained in sulphur, phosphorus, metals, plants, sugar, charcoal and fixed air, although they admit a fixed fire in bodies as they admit inflammable air in water and seek a carbon in metals (in den Metallen einen Kohlenstoff suchen). They do not at all reject it from conviction but rather from obstinacy (Eigensinn) and love of novelty (Neuerungsliebe). ... 

Behrens, H., Ebel, G., 1976. In Behrens, H., Ebel, G. (Eds.), Gases and Carbon in Metals, Physics Data Services, vol. 5. Fachinformationszentrum Energies, Physik, Mathematik, Larlsruhe. 

Gase und Kohlenstoff in Metallen ("Gases and Carbon in Metals"), Springer-Verlag, Berlin, 1976... 

Fro] E. Fromm, T.E. Gebhardt Gasses and Carbon in Metals , Metallurgiya, Moscow, 1978. 

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