Metal thermal reactivities

Schmidt reaction of ketones, 7, 530 from thienylnitrenes, 4, 820 tautomers, 7, 492 thermal reactions, 7, 503 transition metal complexes reactivity, 7, 28 tungsten complexes, 7, 523 UV spectra, 7, 501 X-ray analysis, 7, 494 1 H-Azepines conformation, 7, 492 cycloaddition reactions, 7, 520, 522 dimerization, 7, 508 H NMR, 7, 495 isomerization, 7, 519 metal complexes, 7, 512 photoaddition reactions with oxygen, 7, 523 protonation, 7, 509 ring contractions, 7, 506 sigmatropic rearrangements, 7, 506 stability, 7, 492 N-substituted mass spectra, 7, 501 rearrangements, 7, 504 synthesis, 7, 536-537... 

As mentioned earlier, direct thermal dissociation of water requires temperatures above approximately 2500 K. Since there are not yet technical solutions to the materials problems, the possibility of splitting water instead, by various reaction sequences, has been probed. Historically, the reaction of reactive metals and reactive metal hydrides with water or acid was the standard way of producing pure hydrogen in small quantities. These reactions involved sodium metal with water to form hydrogen or zinc metal with hydrochloric acid or calcium hydride with water. All these... 

Kinetic Studies of Thermal Reactivities of Metal-Metal-Bonded Carbonyls... 

There appears to be, as yet, no general agreement concerning the chemical parameters that control the thermal reactivities of metal carboxylates or the initial step in these reactions. The numerous kinetic studies of these salts have not led to the acceptance of any common pattern of reaction mechanisms. Groups of related reactants, selected to include diverse chemical features which may help major trends to be identified, are surveyed below. 

D-Lactate cytochrome c reductase is inhibited by p-mercuriphenyl sulfonate salts, metal chelators, and dicarboxylic acids such as oxalate and oxaloacetate (Table XVI) 312, 314, 315). According to Nygaard 314), salts (cations) inhibit at the acceptor site, and dicarboxylic acids at the substrate site. Cremona and Singer 315) have studied the inhibitions by metal chelators and by oxalate. They recognized two types of inhibition. One type of inhibition is that which is caused by EDTA or oxalate. This kind of inhibition is reversed immediately upon dilution of the enzyme-inhibitor mixture. The second is that which results from addition of o-phenanthroline. Enzyme preparations treated with o-phenanthroline bind 2 moles of the chelator per mole of Zn +. This complex is stable and inactive, and does not result in the release of Zn. The inactive o-phenanthroline-enzyme complex can be reactivated by dialysis, addition of divalent metal ions such as Zn +, Co +, Mn +, and Fe +, or by incubation at elevated temperatures (<45°) 312, 315-317). It has been shown that heat treatment does not involve the release of o-phenanthroline. The authors suggested that thermal reactivation of the o-phenan-... 

Magnesium is the sixth most abundant metal in the earth s crust, but is exceedingly reactive. It finds wide use as a light alloying material, and is extensively used in the aircraft industry. Although traditionally produced by electrolytic methods, it requires between 8 and 9kWh of electricity per pound of metal. Thermal methods are now widely used. 

Nickel is silver-white, with high electrical and thermal conductivities (both 15% of those of silver) and m.p. 1452°, and it can be drawn, rolled, forged and polished. It is quite resistant to attack by air or water at ordinary temperatures when compact and is therefore often electroplated as a protective coating. Because nickel reacts but slowly with fluorine, the metal and certain alloys (Monel) are used to handle F2 and other corrosive fluorides. It is also ferromagnetic, but not so much as iron. The finely divided metal is reactive to air, and it may be pyrophoric under some conditions. 

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