摘要:

The attractive force between a pyrex glass bead and plate has been measured using a sensitive pendulum-type apparatus. The force required for separation of the bead from the plate has been shown to be strongly time dependent, a phenomenon which appears not to have been reported previously for adhesions in gaseous media. The observed results have been shown to be consistent with the theoretical London – van der Waals interaction. The estimated value of the London force constant is compared with that obtained by other workers.

ISSN:0008-4042    

DOI:10.1139/v55-165

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The anhydrous salts of the long chain fatty acids are known to pass through a number of well-defined mesomorphic forms between the true crystalline solid and the isotropic liquid. The nature of some of these mesomorphic forms has been investigated by a study of their optical properties, electrical conductivity, density, and viscosity. In this paper, results obtained by an optical method are presented for phase transition temperatures of the alkali metal stearates and a number of sodium stearates having substituents in the hydrocarbon chain.

ISSN:0008-4042    

DOI:10.1139/v55-166

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

A pyridine solution of dulcitol hexanitrate evolved gas and became highly colored when warmed to 50 °C.; dilution with water caused the precipitation of 67% of the theoretical amount of a dulcitol pentanitrate. The product was characterized asD,L-galactitol-1,2,4,5,6-pentanitrate by methylation to a monomethyl dulcitol pentanitrate, denitration of the latter, and periodate oxidation of the monomethyl dulcitol obtained. The hexitol derivatives were all obtained in a pure crystalline form. The significance of the data now available on the selective partial denitration by pyridine of hexitol hexanitrates is briefly discussed.

ISSN:0008-4042    

DOI:10.1139/v55-167

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Turbidity measurements in the region immediately above the critical temperature are used to calculate values of (∂p/∂ν)TThese results show that (∂p/∂ν)Tis a continuously variable function of the density to within 0.02 °C. above the critical temperature. The experiments indicate that there exists no region aboveTcthroughout which (∂p/∂ν)T = 0 in ethylene or xenon.

ISSN:0008-4042    

DOI:10.1139/v55-168

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The variation with height of the transmittance in the critical region at various heights in long columns of xenon and ethylene continued to change for several hours after stirring. This change with time is attributed to gravitational settling of large molecular clusters. Other experiments also indicate that a region in which extensive molecular clustering occurs is necessary for an adequate description of phase transitions in the critical region.

ISSN:0008-4042    

DOI:10.1139/v55-169

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The oxidation of gaseous butane has been investigated in the range 260 °C. to 540 °C. with reaction vessels differing greatly in surface to volume ratio. Increased surface area retards the reaction. The rate–temperature relation shows a maximum and a minimum. At low temperatures the rate is very sensitive to temperature, the apparent activation energy being greater than 100 kcal. The abnormal temperature coefficients are shown to arise in part from the differing response to temperature of the branching reactions and the initiation reactions, and in part from the occurrence of competing reactions.

ISSN:0008-4042    

DOI:10.1139/v55-170

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Reaction of the methyl ester of ustilic acid A (15,16-dihydroxypalmitic acid) with a methyl Grignard, oxidation of the glycol grouping, bromination, and hydrogenolysis produced 15-methylhexadecanoic acid. A series of 15-keto acids resulted from reaction of the amide of ustilic acid A with the appropriate Grignard reagent followed by oxidation of the glycol grouping. Infrared absorption characteristics of these compounds are described.

ISSN:0008-4042    

DOI:10.1139/v55-171

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The vapor-phase reaction over activated alumina of 2-ethyltetrahydropyran with aniline gave 1-phenyl-2-ethylpiperidine, 1-phenyl-2-propylpyrrolidine, N-phenyl-4-heptenylamine, and N-phenyl-5-heptenylamine. 2-Methyltetrahydropyran with aniline gave 1-phenyl-2-methylpiperidine, 1-phenyl-2-ethylpyrrolidine, N-phenyl-4-hexenylamine, and N-phenyl-5-hexenylamine. The structures of the cyclic amines were confirmed by independent syntheses. The unsaturated secondary amines were reduced to known N-alkylanilines and degraded by ozonolysis. A mechanism has been proposed to account for the formation of these products.

ISSN:0008-4042    

DOI:10.1139/v55-172

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

A method has been developed for the synthesis of a new heterocyclic system III. When 2-β-chloroethoxybenzyl chloride (XI) was heated with thiourea in alcohol solution, S-(2-β-chloroethoxybenzyl)isothiuronium chloride (XII) was formed which on cleavage with aqueous alkali in high dilution yielded 2,3-dihydrobenzo(f)-1,4-oxathiepin (III). Derivatives of III with substituents such as methyl,t-butyl, chlorine, and nitro in the 7 and 9 positions were prepared in high yields from the corresponding substituted 2-β-chloroethoxybenzyl chlorides. The presence of substituents in the position ortho to the chloroethoxy group of XII had no retarding effect on the cyclization to XIV.

ISSN:0008-4042    

DOI:10.1139/v55-173

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v55-174

出版商:NRC Research Press    

年代:1955

数据来源: NRC