Spontaneous liberation

Kowaluk, E. A., Fung, H-L., Spontaneous liberation of nitric oxide cannot account for in vitro vascular relaxation by S-nitrosothiols. J. Pharmacol. Exp. Ther. 255 (1990),... 

Kots, A. Y., Skurat, A. V., Serienko, E. A., Bulargina, T. V., and Severin, E. S. (1992). Nitric oxide stimulates the cysteine-specific mono(ADP-ribosylation) of glyceralde-hyde-3-phosphate dehydrogenase from human. erythrocytes. FEBS Lett. 300, 9-12. Kowaluk, E. A., and Fung, H. L. (1990). Spontaneous liberation of nitric oxide cannot account for in vitro vascular relaxation by S-nitrosothiols. J. Pharmacol. Exp. Ther. 255,... 

Scheme 2.5 Dimethyl malonate does not spontaneously liberate malonate anions.

Finally, the spontaneous liberation of free radicals via the unimolecular decay of CIII is feasible, since the peroxyl radical is not covalently bound to the porphyrin (pathway 2). This assumption is supported by experimental evidence, which demonstrates that in the presence of excess H202 and no reductant, CIII decays irreversibly into GS and superoxide species in lignin peroxidase [46], horseradish peroxidase [104], myeloperoxidase [51, 105, 106]. 

In the first reports of platinum < >, ruthenium and rhodium hexafluorides their spontaneous liberation of fluorine at ordinary temperatures was mentioned. Clearly... 

The increase in E, with unit change in atomic number of M, appears to be —20 kcal. mole , hence (AuF,) could be >176 kcal. mole . The change in volume of MF, indicated by the relative formula-unit volumes in the NO+[MF,] (cub.) salts Ta, 133-4 Re, 130-7 Os, 129-8 Ir, 129-3 Pt, 129-2 A, shows that the volume of the PtF, group is close to a limiting volume. Presumably the AuF, group would be similar in volume to PtF,", but the fluorine electrons of the former would be more highly polarized than in the latter spontaneous liberation of fluorine might therefore occur. 

Similar free radicals with Al—N bonding but without hydrocarbon groups on the aluminum can be obtained either from the 3 1 adduct of 2,2 -di-pyridyl and aluminum chloride by the action of dilithium-dipyridyl in tetrahydrofuran 96), or from lithium alanate and 2,2 -dipyridyl with spontaneous liberation of hydrogen 96). By analogy with the diethylalanylpyridine radical described above, the following structure for the complex Al(dipyridyl)a can be suggested ... 

We have compared the chemical (i.e., spontaneous ) NO-generating activities of a series of S-nitrosothiols versus their vasodilating properties and observed that these two characteristics were not correlated (Kowaluk and Fung, 1990). Chemical degradation of S-nitrosothiols to release NO was enhanced in the presence of N-acetylpenicillamine and inhibited by 100 U/ml superoxide dismutase. However, the relaxant effects of S-nitrosothiols were enhanced by superoxide dismutase and diminished by N-acetylpenicillamine. These results argue against the spontaneous liberation of NO as a predominant mechanism of S-nitrosothiol action, a conclusion that was subsequently supported by Mathews and Kerr (1993). 

Decomposition (chemical) A reaction in which the molecules of a chemical break down to its basic elements, such as carbon, hydrogen, or nitrogen, or to more simple compounds. This often occurs spontaneously, liberating considerable heat and often large volumes of gas. 

A characteristic feature of plasticized pol3miers is syneresis, the spontaneous liberation of the liquid phase. S3meresis may take place during both molding of the samples and in complete products. 

Recently, new methods such as supercritical fluids, spontaneous liberation of PHA, dissolved air flotation, and air classification, are being investigated and probably promise to have much more success. Improvement of these new extraction and purification methods should cause an optimal recoveiy of PHA, with a high purity and recoveiy level at a low production cost. 

Bacterial strains such as E. coli which are capable of spontaneously liberating PHA from cells are favourably used in this system. Currently, spontaneous liberation is drawing much attention since no chemicals are... 

When the R group of the primary amine is an alkyl group as opposed to an aryl group, then the resulting diazonium salt is highly unstable and is too reactive to be isolated. It can spontaneously liberate nitrogen gas to form a carbocation, which then reacts in a variety of ways. 

Jung, I., Phyo, K., Kim, K., Park, H., and Kim, 1.2005. Spontaneous liberation of intracellular polyhydroxy-butyrate granules in Escherichia coli. Res Microbiol 156 865-73. 

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