摘要:

The photolysis of dimethyl mercury in solution inn-hexane has been studied over the temperature range +25 °C. to −80 °C. The results indicate that methane is produced by an abstraction reaction involving the solvent, and ethane is produced by dimerization of methyl radicals. The mechanism of the reaction is discussed, and it is concluded that the abstraction reaction involves radicals possessing considerable energy carried over from the photodissociation.

ISSN:0008-4042    

DOI:10.1139/v54-058

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Evidence is presented which confirms the presence in atisine and isoatisine of vinylamine double bonds, an N-(β-hydroxyethyl) group, an exocyclic methylene group, and a secondary hydroxyl in an allylic relation to the latter. The size and substitution of the heterocyclic ring is discussed. The pyrolysis of atisine and isoatisine hydrochlorides to give a C20H29ON base is described.

ISSN:0008-4042    

DOI:10.1139/v54-059

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The rates of addition of methyl radicals, produced by the photolysis of acetone between 140 °C. and 240 °C, to unsaturated hydrocarbons were determined by two independent methods. From the kinetics of the addition and the methyl radical combination reactions, addition of methyl radicals to ethylene, propylene, acetylene, and butadiene was found to proceed with activation energies of 7.0, 6.0, 5.5, and ∼2.5 kcal. respectively and steric factors of the order of 10−4.

ISSN:0008-4042    

DOI:10.1139/v54-060

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The viscosity of gases is examined using the theory of corresponding states. The curve of reduced viscosity plotted against reduced temperature is compared with the theoretical curves obtained for several intermolecular potentials. The approximate Sutherland equation gives the best fit and it is suggested that this be used to extrapolate viscosities to high temperatures where experimental data are not available. The reduced viscosity – reduced temperature plot can be used for estimating the viscosities of simple gases from critical data, or critical data from the viscosities.

ISSN:0008-4042    

DOI:10.1139/v54-061

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

A relation between intrinsic viscosity and the sign of heat of mixing of a linear polymer in different solvents has been predicted by Alfrey, Bartovics, and Mark. To verify this, the intrinsic viscosities and heats of mixing at one concentration for two samples of polyvinyl acetate in six solvents were determined. The heats of mixing have been measured with a Tian–Calvet microcalorimeter especially designed for slow processes and having a sensitivity of one thousandth of a calorie per hour. The results generally agree with the above prediction. Furthermore, the heats of mixing of two fractions of polyvinyl acetate in three solvents have been measured over a range of low concentrations to study the behavior of the quantityBfrom the theory of van Laar, Scatchard, and Hildebrand on energy of mixing of nonelectrolytes. It was found thatBgoes through a minimum at low concentrations when the mixing process is exothermic. This effect may be explained by the existence of a critical concentration below which entanglement between macromolecules ceases. For a poor solvent,Bseems to be constant at high dilution.

ISSN:0008-4042    

DOI:10.1139/v54-062

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Dehydrohalogenation ofcis-1,2-dichloro-1-alkenes, RCCl═CHCl, with potassium hydroxide in butanol has been used to prepare a number of new 1-chloro-1-alkynes, viz. 1-chloro-1-propyne-d3, 1-chloro-1-propyne, 1-chloro-1-butyne, and 1-chloro-1-pentyne in good yields. The last three compounds were also prepared by chlorination of 1-propyne, 1-butyne, and 1-pentyne with sodium hypochlorit

ISSN:0008-4042    

DOI:10.1139/v54-063

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The shape of the calibration curve obtained with a commercial Falling Drop apparatus has been investigated for drops varying in viscosity and surface tension and in media of varying solvent power. Drop velocity affects drop shape when the viscosity of the drop substance is low, and drop volume when the medium exerts solvent action on the drop. "End effect" appears to be significant even when "wall effect" is large.

ISSN:0008-4042    

DOI:10.1139/v54-064

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

Several analogues of 2,2′-bipyridyl, with isoquinoline, thiazole, and pyridine rings in various combinations, have been synthesized, and the effect of substituent groups in certain positions in the molecules studied with respect to their ability to react with cuprous and ferrous ion (the "cuproin" and "ferroin" reactions). The results agree with earlier work, and emphasize the desirability of two substituent groups "ortho" to the nitrogen atoms if a stable and sensitive cuprous ion reagent is wanted. The presence of one ortho substituent makes the reagent ineffective toward reaction with ferrous ion. Two of the compounds synthesized had groups in positions which did not allow a coplanarcisconfiguration of the molecule, and only in these cases were dipicrates formed; this situation is explained by assuming that hydrogen bond formation between the nitrogen atoms is not possible.

ISSN:0008-4042    

DOI:10.1139/v54-065

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The production of acid from two commercial brands of chloroform, on exposure to Co60gamma-rays and high energy X rays from a betatron, has been measured. Inhibitor-free chloroform liberates acid in amounts varying linearly with the radiation dose. The specific yield, in micromoles of acid produced per liter of chloroform per kiloroentgen, varies inversely as the square root of the dose rate. The specific yields are slightly less for betatron radiations, compared with Co60gamma-rays. The average lifetime of the free radical chains is about one second.

ISSN:0008-4042    

DOI:10.1139/v54-066

出版商:NRC Research Press    

年代:1954

数据来源: NRC

摘要:

The ketol, 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-propanone, was subjected to ethanolysis and found to yield the four propylphenols which can be isolated from the ethanolysis products of isolated conifer lignin and of conifer lignininsitu. The significance of this finding is briefly discussed.

ISSN:0008-4042    

DOI:10.1139/v54-067

出版商:NRC Research Press    

年代:1954

数据来源: NRC