Thermodynamic metalations

Thermodynamically, metallic aluminum has a high chemical energy of 788.61 kJ/g [1]. We propose a new system for the treatment of waste aluminum. In previous paper, we demonstrated that aluminum powder can react with water at normal pressure to generate hydrogen, and the temperature dependence of the generation rate conforms to the Arrhenius equation with an activation energy of 69 kJ/mol [2]. The coproduction of hydrogen and aluminum hydroxide from... 

In this case, 20% of thermodynamically metallated propargylic derivative leads to the corresponding cyclic product as described in Scheme 7-18 with a silyl ether instead of a methyl ether in 25. 

Electrolytes, Thermodynamics - Metal-Air Batteries Photolysis of Water... 

Thermodynamically, metals can only corrode by anodic dissolution if an associated cathodic reaction with a more positive equilibrium is available. As noble metals such as gold have particularly high electrode potentials, they have excellent corrosion resistance. However, if an alternative cathodic reaction which has a moK positive potential becomes available, or if the potential of the metal dissolution reaction is reduced by complex formation, corrosion again becomes... 

Meyers AI, Williams DR. Asymmetric alkylation of acyclic ketones via chiral metallo enamines-effect of kinetic vs thermodynamic metalations. J. Org. Chem. 1978 43 3245-3247. 

The equations of electrocapillarity become complicated in the case of the solid metal-electrolyte interface. The problem is that the work spent in a differential stretching of the interface is not equal to that in forming an infinitesimal amount of new surface, if the surface is under elastic strain. Couchman and co-workers [142, 143] and Mobliner and Beck [144] have, among others, discussed the thermodynamics of the situation, including some of the problems of terminology. 

Figure A2.4.9. Components of the Galvani potential differenee at a metal-solution interfaee. From [16], A2.4.5.2 INTERFACIAL THERMODYNAMICS OF THE DIFFUSE LAYER...

Stella A ef al 1996 Comparative study of thermodynamic properties of metallic and semiconducting nanoparticles in a dielectric matrix Mater. Res. Soc. Symp. Proc. 400 161... 

Olefin Isomerization- a variety of transition metal (RhCl3 H20) catalyst will isomerize doubles bonds to more thermodynamically favorable configurations (i.e. more substituted, trans, conjugated)... 

The last isomerization is remarkable in that the triple bond can shift through a long carbon chain to the terminus, where it is fixed as the (kinetically) stable acetylide. The reagent is a solution of potassium diami no-propyl amide in 1,3-di-aminopropane. In some cases alkali metal amides in liquid ammonia car also bring about "contra-thermodynamic" isomerizations the reactions are successful only if the triple bond is in the 2-position. 

This isomerization, which must proceed through a 1,2,3-trienylanine, is not "contra-thermodynamic", since with a catalytic amount of potassium tert.-butoxide the same result is obtained. Enyne ethers, H2C=CH-CsC-0R, undergo a similar conversion into HCeC-CH=CH-OR upon interaction with alkali metal amides in liquid NH3, followed by hydrolysis . Enyne sulphides, H2C=CH-CsC-SR, and the hydrocarbons H2C=CH-CsC-R (R = or phenyl) give only tars or polymeric products under... 

Marin, D. Mendicuti, F. Polarographic Determination of Composition and Thermodynamic Stability Constant of a Complex Metal Ion, /. Chem. Educ. 1988, 65, 916-918. 

Although the chiral recognition mechanism of these cyclodexttin-based phases is not entirely understood, thermodynamic and column capacity studies indicate that the analytes may interact with the functionalized cyclodextrins by either associating with the outside or mouth of the cyclodextrin, or by forming a more traditional inclusion complex with the cyclodextrin (122). As in the case of the metal-complex chiral stationary phase, configuration assignment is generally not possible in the absence of pure chiral standards. 

Reaction with Metals. Thermodynamic considerations for the reaction... 

Nuclear Applications. Powder metallurgy is used in the fabrication of fuel elements as well as control, shielding, moderator, and other components of nuclear-power reactors (63) (see Nuclearreactors). The materials for fuel, moderator, and control parts of a reactor are thermodynamically unstable if heated to melting temperatures. These same materials are stable under P/M process conditions. It is possible, for example, to incorporate uranium or ceramic compounds in a metallic matrix, or to produce parts that are similar in the size and shape desired without effecting drastic changes in either the stmcture or surface conditions. OnlyHttle post-sintering treatment is necessary. 

Ceramic—metal interfaces are generally formed at high temperatures. Diffusion and chemical reaction kinetics are faster at elevated temperatures. Knowledge of the chemical reaction products and, if possible, their properties are needed. It is therefore imperative to understand the thermodynamics and kinetics of reactions such that processing can be controlled and optimum properties obtained. 

Ma.nufa.cture. Nickel carbonyl can be prepared by the direct combination of carbon monoxide and metallic nickel (77). The presence of sulfur, the surface area, and the surface activity of the nickel affect the formation of nickel carbonyl (78). The thermodynamics of formation and reaction are documented (79). Two commercial processes are used for large-scale production (80). An atmospheric method, whereby carbon monoxide is passed over nickel sulfide and freshly reduced nickel metal, is used in the United Kingdom to produce pure nickel carbonyl (81). The second method, used in Canada, involves high pressure CO in the formation of iron and nickel carbonyls the two are separated by distillation (81). Very high pressure CO is required for the formation of cobalt carbonyl and a method has been described where the mixed carbonyls are scmbbed with ammonia or an amine and the cobalt is extracted as the ammine carbonyl (82). A discontinued commercial process in the United States involved the reaction of carbon monoxide with nickel sulfate solution. 

D. R. StuU and G. C. Sinke, Thermodynamic Properties of the Metals, American Cbemical Society, Washington, D.C., 1956. 

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