Nickel temperature effect

Myers, J. R., Crow, W. B., Beck, F. H. and Saxer, R. K., Observation on the Anodic Behaviour of Nickel and Chromium Surface Topography and Temperature Effect , Corrosion, 22, 32 (1966)... 

References to a number of other kinetic studies of the decomposition of Ni(HC02)2 have been given [375]. Erofe evet al. [1026] observed that doping altered the rate of reaction of this solid and, from conductivity data, concluded that the initial step involves electron transfer (HCOO- - HCOO +e-). Fox et al. [118], using particles of homogeneous size, showed that both the reaction rate and the shape of a time curves were sensitive to the mean particle diameter. However, since the reported measurements refer to reactions at different temperatures, it is at least possible that some part of the effects described could be temperature effects. Decomposition of nickel formate in oxygen [60] yielded NiO and C02 only the shapes of the a—time curves were comparable in some respects with those for reaction in vacuum and E = 160 15 kJ mole-1. Criado et al. [1031] used the Prout—Tompkins equation [eqn. (9)] in a non-isothermal kinetic analysis of nickel formate decomposition and obtained E = 100 4 kJ mole-1. 

In 1992, Crabtree and co-workers reported the first nickel catalyst effective for silane alcoholysis.161 The complex, [Ni(tss)]2 (tss = salicylaldehyde thiosemicarbazone), bears a ligand that contains O and N donor groups and a semicarbazide sulfur. Alcoholysis of Et3SiH with ethanol or methanol occurs at room temperature in 50% dimethyl sulfoxide-benzene. However, the reaction is inhibited in the presence of strong donor ligands, H2, or atmospheric pressure of CO. 

Recent work by Selwood (9), based on changes in the magnetization of nickel during chemisorption of ethylene, indicates that ethylene is associatively adsorbed on bare nickel. He suggests that the discrepancy between this result and the dissociative chemisorption indicated by the infrared experiments is due to factors such as the relative activity of the sample surfaces and temperature effects caused by the heat of chemisorption. Low-temperature infrared experiments in which ethylene is studied at —78° C. are expected to provide evidence on the importance of the above factors in determining the course of ethylene chemisorption. 

The catalyst was 100 ml of American Cyanamid HDS-3A, a 1/16-inch diameter extrudate of nickel-molybdenum-alumina. It was diluted with inert, granular alpha-alumina to provide a bed depth of 18 inches in the middle section of a 0.96-inch ID vertical reactor with a 5/16-inch OD internal thermocouple well. The catalyst was progressively more dilute toward the top of the bed to minimize exothermic temperature effects, and end sections were packed with alpha-alumina to provide for preheat and cooling zones. 

Gao, M., Chen, S. F., Chen, G. S., and Wei, R. P., Environmentally Enhanced Crack Growth in Nickel-Based Alloys at Elevated Temperatures, in Elevated Temperature Effects on Fatigue and Fracture, ASTM STP 1297, R. S. Piascik, R. P. Gangloff, and A. Saxena, eds., American Society for Testing and Materials, West Conshohocken, PA (1997), 74-84. 

Kolts, J. and Sridhar, N., Temperature Effects in Localized Corrosion, Corrosion of Nickel-Base Alloys, R. C. Scarberry, Ed., ASM International, Metals Park, OH, 1985, pp. 191-198. 

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