Hydrogen evolution single phases

A specific advantage of this method is the possibility for the variation of the metals and the fact that preparative amounts of the products are accessible as coarse crystalline and single phase products in short reaction times. The reactions may be interpreted as the dissolution of an electropositive metal in a nitrido analogous, polymeric acid (Si(NH)2) by the evolution of hydrogen. 

Abyaneh, M.Y. (2004) Kinetics of single-phase electrocrystallization processes I growth of paraboloids with concurrent evolution of hydrogen. Journal of the Electrochemical Society, 151, C737. 

The cyclic voltammogram of Fig. 54a is not Hilly symmetrical. The distortion probably originates from the catalytic discharge of protons and evolution of hydrogen in the solid phase. These results suggest the possibility that by using cyclic voltammetry with a single crystal, the reduction potential of solid heteropoly compounds can be measured and that the effects of constituent elements described below can be made clearer. 

F. Habashi 1965 Validity of a single kinetic law irrespective of the metal, composition of aqueous phase, and evolution of hydrogen when no insoluble products, scales or films are formed... 

Structural data from in situ high pressure ND studies are analyzed in [163], they show that the O-H and H- - -O distances follow the same correlations as have been established at ambient conditions on different compounds. Another pressure effect is the evolution of the double-welled, hydrogen bond potential into a single-well potential. According to ab initio calculations, the bulk modulus must have a discontinuity at this point and this can be an indication for hydrogen bond symmetrization it means that the hydrogen bond symmetrization is a second-order phase transition. 

The oxidation of alkanes by r-butyl hydroperoxide (TBHP) has been catalysed by titanium alkoxides, producing the corresponding alcohols and ketones. A radical mechanism is proposed in which r-butoxyl radical formed from TBHP and titanium alkoxide initiates the reaction. The evolution of oxygen (from the decomposition of peroxide) and the abstraction of hydrogen from alkane to form alkyl radical occur competitively. A method for the determination of both the primary and secondary KIEs at a reactive centre based on starting-material reactivities allows the determination of the separate KIEs in reactions for which neither product analysis nor absolute rate measurements are applicable. It has been applied to the FeCls-catalysed oxidation of ethylbenzene with TBHP, which exhibits both a primary KIE and a substantial secondary KIE the findings are in accordance with previous mechanistic studies of this reaction. The oxidation of two l-arylazo-2-hydroxynaphthalene-6-sulfonate dyes by peroxy-acids and TBHP catalysed by iron(III) 5,10,15,20-tetra(2,6-dichloro-2-sulfonatophenyl)porphyrin [Fe(ni)P] is a two-step process. In single turnover reactions, dye and Fe(in)P compete for the initially formed OFe(IV)P+ in a fast reaction and OFe(IV)P is produced the peroxy acid dye stoichiometry is 1 1. This is followed by a slow phase with 2 1 peroxy acid dye stoichiometry [equivalent to a... 

In principle, in situ XRD should be suitable to follow the structural evolution of the active phase directly, i.e., with no interruption of the activation process and using a single sample for all diffraction experiments. However, since different reaction cells would be used for this purpose, the serious disadvantage of uncontrolled gas flow and thus ill-defined reaction kinetics are seen. In Fig. 2.16, part of a series of diffraction patterns from in situ activation experiments of catalyst 3 with pure hydrogen are shown. The temperature interval is that of maximum water... 

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