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doi: 10.1002/jctb.5010051001pmid: N/A
When an equimolar mixture of dimethylphosphoramidic dichloride and hexamethylphosphoramide is heated (120–200°), radical exchange (NMe2 for Cl) takes place and tetramethylphosphorodiamidic chloride is formed. This radical exchange follows a first‐order reaction at 120°. An equimolar mixture of the dichloride and the amide undergoes polymerisation at room temperature, and after 6–8 days solidifies to a crystalline mass. This mass appears to be a mixture of a salt‐like addition product of the dichloride and the amide approaching a hexameric state, and the unchanged dichloride and amide. On heating, it undergoes radical exchange with the formation of tetramethylphosphorodiamidic chloride which yields bisdimethylaminophosphonous anhydride (schradan) on treatment with potassium hydroxide in toluene1.
MacDonald, P.; Sweett, F.; Hall, C. C.
doi: 10.1002/jctb.5010051002pmid: N/A
The isomer distribution in the C6‐hydrocarbons from synthesis products has been shown to be markedly dependent on the temperature at which synthesis is effected, and it has been established that this result is not due to secondary isomerization of the initial reaction products.
doi: 10.1002/jctb.5010051003pmid: N/A
The size of gas bubble produced from an open‐ended tube immersed in a liquid can be derived by equating surface tension and buoyancy forces. The equations do not apply, however, when the gas flow is large as in many industrial fermentations, and porous elements are therefore often used to provide many orifices and a low gas‐flow through each. Even this technique fails if a mycelial growth is formed during the fermentation because the bubbles coalesce in the fermenter. Mechanical agitation was examined by the author by measuring gas‐to‐liquid transfer rates using paper pulp to imitate the mycelium, since this was found to interfere chemically with the reaction. Without agitation, the paper pulp reduced the transfer rate by a factor of twenty. With simple paddle agitation in conjunction with a sparge ring, the effect of pulp was reduced to a factor of seven but with a high‐speed agitator used with an open tube gas inlet, the factor was reduced to two.
doi: 10.1002/jctb.5010051004pmid: N/A
An ultracentrifugal examination of groundnut protein treated with various bases has been made. It has been shown that only bases with a dissociation constant higher than about 10−1 cause an appreciable reduction in the molecular weight of the protein and are suitable for fibre formation with the protein.
Gaensslen, H.; MacKenzie, H. A. E.
doi: 10.1002/jctb.5010051005pmid: N/A
When reactions in non‐isothermal systems are treated kinetically, complicated differential equations arise, as well as ‘integral rate constants’ of the form \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop \smallint \limits_o^t $\end{document} k(t)dt. Methods are described for evaluating the integrals and for solving numerically the differential equations which are obtained for both reversible and irreversible reactions.
Richardson, G. M.; Malthus, R. S.
doi: 10.1002/jctb.5010051006pmid: N/A
An isopiestic technique has been used for observing the static control of humidity by saturated salt solutions and by paired salt hydrates. Many new values within the range 7% to 60% relative humidity at 25°C have been obtained, using saturated solutions of highly soluble salts. Difficulties encountered in using paired salt hydrates to control humidity at low levels have been described.
doi: 10.1002/jctb.5010051007pmid: N/A
A method of evaluating the temperature drop across a condensate film is evolved, based on the fact that for many substances the group of physical constants (k3p2λg/μ)1/4 appearing in the Nusselt equation is nearly independent of temperature. A graphical solution will give the desired temperature drop, thus eliminating trial‐and‐error methods.
Downing, A. L.; Truesdale, G. A.
doi: 10.1002/jctb.5010051008pmid: N/A
The effects of a number of factors on the rate of solution of oxygen in fresh and saline water were investigated experimentally to provide information about re‐aeration in a polluted estuary.
doi: 10.1002/jctb.5010051009pmid: N/A
The specific gravity‐temperature coefficients of a wide range of coal tars were correlated with the specific gravity (S.G.) by the formula
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