摘要:

The methyl groups of the pyrroles Iaand IIareact with sulphuryl chloride to give dichloromethyl derivatives which hydrolyze to aldehydes. The pyrrole Iaalso forms a trichloromethyl derivative which hydrolyzes to the corresponding acid. Alkaline decarboxylation of the latter gives opsopyrrole-dicarboxylic acid, IVa.

ISSN:0008-4042    

DOI:10.1139/v55-068

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The reactions initiated in hydrogen–propylene mixtures by Hg(3P1) atoms were studied over the temperature range from room temperature to 320 °C. At 260° and above, the rate of formation of propane and the rate of pressure decrease are linear functions of the hydrogen pressure. This effect is attributed to the reaction C3H7+H2 = C3H8+H and its activation energy is estimated to be equal to or slightly greater than 12.5 kcal. per mole. This is 1.2 kcal. per mole greater than the corrected value for the activation energy of the analogous reaction C2H5+H2 = C2H6+H. The ratiokcombination/kdispropotionationis estimated to be approximately 2.0 at room temperature in the case of isopropyl radicals.

ISSN:0008-4042    

DOI:10.1139/v55-069

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The second virial coefficients of neon have been determined in the temperature range 0° to 700 °C. and the pressure range 10 to 80 atmospheres. These data were combined with published low temperature (−150° to 0 °C.) second virial data, to investigate the intermolecular potentials of neon using both a Lennard-Jones potential, with a 9th and 12th power repulsion term, and also a modified Buckingham exponential–six potential. The agreement between observed and calculated values ofB(T) was excellent for both the exponential–six and the Lennard-Jones 12:6 potentials and slightly less satisfactory for the Lennard-Jones 9:6 potential.

ISSN:0008-4042    

DOI:10.1139/v55-070

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The degradation of carrageenin in buffered aqueous solution at pH 7.0 has been studied over the temperature range 60° to 101 °C. by following the change in viscosity and reducing properties. Kinetic analysis indicates the occurrence of two reactions: (a) an initial rapid degradation representing only about 0.3% of the complete hydrolysis, followed by (b) a first-order random degradation havingk = 2.75 × 1013 e−29,200,/RT hr−1. The latter reaction becomes important at temperatures above 60 °C. The results indicate that carrageenin is more unstable than would be expected of a simple 1–3 galactan, and that two types of weak linkage are involved in the structure of the polysaccharide.

ISSN:0008-4042    

DOI:10.1139/v55-071

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Dihydrogelsemine reacts with diethyl azodicarboxylate yielding a carbinolamine which forms a methyl ether. Both this ether and the carbinolamine base can be oxidized by chromic acid to the same neutral lactam. That there has been no rearrangement of the carbon skeleton during these reactions is shown by reduction of the methyl ether of the carbinolamine with sodium borohydride to dihydrogelsemine and by reduction of the lactam with lithium aluminum hydride to tetrahydrodesoxygelsemine. It is concluded that both dihydrogelsemine and gelsemine contain a methylene group adjacent to N(b), and from the infrared spectrum of the lactam of dihydrogelsemine, N(b)appears to be part of a five-membered ring.

ISSN:0008-4042    

DOI:10.1139/v55-072

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The response probability of a 4π-counter has been examined and conditions determined for which the response probability is unity to within ± 0.1% for a range of nuclides. Variables examined have been the effect of polarization potential, discriminator bias, source location, counting rate, counter gas purity, thickness of conductor on source mount, for particles of various energies and from various modes of disintegration.

ISSN:0008-4042    

DOI:10.1139/v55-073

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The virial coefficients of xenon have been measured in the temperature and pressure range described. The results are compared with previous measurements.

ISSN:0008-4042    

DOI:10.1139/v55-074

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

Spruce sulphite liquor was extracted with butyl acetate. By means of solvent fractionation, chromatography, and countercurrent distribution, vanilloyl methyl ketone, vanillin, dihydroconiferyl alcohol, 3,3′-dimethoxy-4,4′-dihy-droxystilbene, and a new phenolic compound, C20H24O5, were isolated and identified.

ISSN:0008-4042    

DOI:10.1139/v55-075

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

With the object of preparing a cellulose ether containing diazotizable amino groups, seven different forms of cellulose, or cellulose derivatives, were treated with 10 different reagents under a variety of conditions. Reasons why only one reagent under one set of conditions gave a product with a substantial degree of substitution (0.35) and with satisfactory physical properties are presented. This resulting ether, the ω-(P-aminoacetophenone) ether of cellulose, was prepared by the reaction between ω-chloro-P-aminoacetophenone and ethanol-washed soda-cellulose (from wood pulp, cotton, paper, or rayon). It can be (a) diazotized and coupled with any of the usual reagents to yield cellulose-azo colors, (b) xanthated, before or after coupling, and spun as rayon filament; if uncoupled at this point it can be diazotized and coupled, (c) dyed directly with acid dyes, (d) rendered organo-soluble by nitration, and (e) carboxymethylated after coupling to yield colored, water-soluble derivatives. It is insoluble in the usual cellulose reagents, and is as stable to acid and alkaline hydrolysis as cellulose.

ISSN:0008-4042    

DOI:10.1139/v55-076

出版商:NRC Research Press    

年代:1955

数据来源: NRC

摘要:

The need for a Bunsen-type isothermal calorimeter operating as close as possible to the standard thermochemical reference temperature, 25 °C., was fulfilled by means of diphenyl ether (m.p. 26.9 °C.) as the working substance. The instrument was calibrated electrically by comparison with the ice calorimeter and the constant was found to be 19.01 ± 0.02 cal. per gm. of mercury. From this and other known properties of diphenyl ether the density of the solid at the melting point was estimated at 1.188 gm. per ml. Check determinations based on the heat of vaporization of water showed that for such measurements the mantle of solid ether must first be melted inside by an amount equivalent to the heat to be measured. The calorimeter was operated in a large water-thermostat kept constant to within 0.001 °C. With highly purified diphenyl ether there was no noticeable temperature drift during the measurements. Quantities of heat up to 600 cal. could be measured with a reproducibility of the order of 0.2%. The new calorimeter is simpler to operate than the ice calorimeter and its sensitivity is more than three times as great.

ISSN:0008-4042    

DOI:10.1139/v55-077

出版商:NRC Research Press    

年代:1955

数据来源: NRC