Global solutions of the homogeneous complex Monge-Ampère equation and complex structures on the tangent bundle of Riemannian manifolds

Research in part supported by an NSF grant     

A novel thermal rearrangement of N-cyano-N-(α-cyanobenzhydryl)-aniline

The title compound1 is rearranged, when refluxed with toluene, to the carbodiimide5 and the cyanoaniline7. While rearrangements analogous to the transformation1→5 have recently been observed, the transformation1→7 is novel.     

Noise levels and hearing thresholds in the drop forging industry

A-weighted equivalent continuous noise levels for hammer and press operations in a drop-forging industry were determined using both tape recordings of the noise and personal noise dosimeters. The results indicated average A-weighted Leq values of 108 dB for hammer operators and 99 dB for press operators. Comparison of hearing level statistics for 716 hammer and press operators and 293 control subjects indicated the severe hazard to hearing of impact noise exposures. For mean exposure times of less than 10 years, hearing levels for the press (99 dB) and hammer (108 dB) operator age groups are nearly identical, and in the latter case are less than those predicted for exposure to equivalent continuous noise. For long-term exposures of 10 years or more, the results of this study indicate that hearing losses resulting from impact noise in the drop-forging industry are as great or greater than those resulting from continuous noise.     

Kinetics of thermal decomposition of n-alkyl-n′-methoxydiazene-n-oxides in the gas phase

Conclusions The kinetics of the thermal decomposition of N-methyl-, N-t-butyl-, and N-neopentyl-N-methoxydiazene-N-oxides have been studied in the gas phase. The reactions are first order with activation parameters: E 204, 148, and 206 kJ/mole, log(A/sec^–1) 14.5, 13.3, and 14.6, respectively. A mechanism has been proposed for the decomposition of the MeN- and t-BuCH₂N-derivatives by the primary homolytic rupture of the N-OMe bond, and in the case of the t-BuN-analog, via a five-membered cyclic transition state with migration of a -H to the N atom.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1506–1509, July, 1988.     

Synthesis of 1,1-bis(methoxy-NNO-azoxy)-3,3,3-trinitropropane from 1,1-bis(methoxy-NNO-azoxy)ethene and nitroform

A reaction of 1,1-bis(methoxy-NNO-azoxy)ethene with nitroform at ∼20 °C gave 1,1-bis-(methoxy-NNO-azoxy)-3,3,3-trinitropropane.     

Mass transfer of zinc-containing compounds during filtration combustion in the counterflow regime: 3. Mass transfer at a low content of the zinc-containing component in the initial stock

The regularities of filtration combustion and of the mass transfer of zinc-containing products from model stock compositions with a low content of the zinc-containing component were experimentally studied over a range of governing parameters. The parameters of the combustion of stock samples, degree of extraction of zinc-containing products into sublimate from the condensed sample, and chemical form of the zinc-containing compounds released were determined. The results obtained were discussed.