Huang conditions

Hydrazones of thiochroman-4-ones are converted into thiochromans under Wolff-Kishner-Huang conditions and into the azo dimers by silver oxide. Fisher indolization of the phenylhydrazones (33) gives 6,ll-dihydrobenz[6]indolo[2,3-d]thiopyrans (34), which by hydride loss form the thiopyrylium salts (35), or on dehydrogenation produce the pseudoazulenes (36) (heterocyclic analogs of the carcinogen, benz[a]-carbazole), as shown in Scheme 6. ... 

It can be shown that the HUANG conditions (3.118) follow directly from the transformation properties of the force on an atom under a rigid body rotation of the crystal [3.18]. As a result of (3.117,118), the number of independent components of is reduced to 21. 

In Section XIII, we made a connection between the curl condition that was found to exist for Bom-Oppenheimer-Huang systems and the Yang-Mills field. Through this connection we found that the non-adiabatic coupling terms can be considered as vector potentials that have their source in pseudomagnetic... 

Another subject with important potential application is discussed in Section XIV. There we suggested employing the curl equations (which any Bohr-Oppenheimer-Huang system has to obey for the for the relevant sub-Hilbert space), instead of ab initio calculations, to derive the non-adiabatic coupling terms [113,114]. Whereas these equations yield an analytic solution for any two-state system (the abelian case) they become much more elaborate due to the nonlinear terms that are unavoidable for any realistic system that contains more than two states (the non-abelian case). The solution of these equations is subject to boundary conditions that can be supplied either by ab initio calculations or perturbation theory. 

The classical procedure for the Wolff-Kishner reduction—i.e. the decomposition of the hydrazone in an autoclave at 200 °C—has been replaced almost completely by the modified procedure after Huang-Minlon The isolation of the intermediate is not necessary with this variant instead the aldehyde or ketone is heated with excess hydrazine hydrate in diethyleneglycol as solvent and in the presence of alkali hydroxide for several hours under reflux. A further improvement of the reaction conditions is the use of potassium tcrt-butoxide as base and dimethyl sulfoxide (DMSO) as solvent the reaction can then proceed already at room temperature. ... 

Bohm, D., Huang, K., and Pines, D., Phys. Rev. 107, 71, Role of subsidiary conditions in the collective description of electron interactions. ... 

Bunnett (1991) expresses doubts that the aryldiazene can be formed at all under these strongly basic conditions, after Huang and Kosower (1968) showed that phenyldiazene is destroyed in water at pH 13.8 (25 °C) with a half-life of <10s, doubtless via C6H5-N2. In addition, Broxton s proposal (Scheme 8-53) does not provide a satisfying explanation of why the ortho halogen has such a strong effect in favor of the carbanion mechanism. 

The reaction has been investigated experimentally by Huang and Dauerman9 in a batch reaction carried out with initial conditions given in Table 5.39. 

Ehrlich HL (2002) Interactions between microorganisms and minerals under anaerobic conditions. In Huang PM, Bollag J-M, Senesi N (eds) Interactions between soil particles and microorganisms. Impact on the terrestrial ecosystem, vol 8, IUPAC Series on Analytical and Physical Chemistry of Environmental Systems. Wiley, Chichester, UK, pp 459-494... 

The NO binding to Hb oxygenated to various degrees, was also studied with EPR and UV/Vis spectroscopy by Huang and coworkers (2001). Contrary to the results of Gow et al. (1999), NO binding did not show cooperativity under conditions stabilizing either the R-state (0.01 M phosphate) or the T state (0.1M phosphate), both with Hb or with whole blood. 

Clinical signs of peripheral neuropathy similar to those seen in human occupational exposures to w-hexane can be produced in rats via the inhalation and oral routes, but not in other test species (Altenkirch et al. 1982 De Martino et al. 1987 Dunnick et al. 1989 Frontali et al. 1981 Huang et al. 1989 IRDC 1981 Krasavage etal. 1980 NTP 1991 Schaumburg and Spencer 1976 Takeuchi etal. 1980). Paranodal axonal swelling in mice (Dunnick et al. 1989 NTP 1991) and leg weakness in chickens (Abou-Donia et al. 1985) can be produced with inhalation exposure to -hexane, but these conditions do not progress to the severe neurotoxicity observed in humans and rats. The molecular mechanism... 

Huang and Tang49 trained a neural network with data relating to several qualities of polymer yarn and ten process parameters. They then combined this ANN with a genetic algorithm to find parameter values that optimize quality. Because the relationships between processing conditions and polymer properties are poorly understood, this combination of AI techniques is a potentially productive way to proceed. 

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