摘要:

Increased acetone concentration in aqueous solutions of sodium hydroxide lowers the specific conductivity to a marked degree. This cannot be satisfactorily explained by viscosity change only, but is probably accounted for by a combination of changes in both viscosity and dielectric properties of the solutions. An empirical equation is suggested.

ISSN:1923-4287    

DOI:10.1139/cjr36b-023

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

A study has been made of the stabilizing effect of potato, corn, wheat and rice starches in phosphate, tartrate and combination baking powders under widely differing conditions of storage. The stabilizing effect was found to depend on the size of the starch granule, decreasing efficiency being obtained with increasing granular size in the following order: rice, wheat, corn, potato. Microscopic observations were made to determine the physical effect of the starch. Small wheat granules were found to be more efficient than large ones, and finely powdered wheat starch more efficient than coarse wheat starch. The stability is greater with increasing particle size of acid constituent, and the crystal form of the latter is also important. The difference in stability lent by the various starches is increasingly accentuated with increasing fineness of acid constituent. The stability decreases rapidly with rise in relative humidity. The moisture take-up of potato, corn and wheat starches at different humidities has been measured.

ISSN:1923-4287    

DOI:10.1139/cjr36b-024

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

A description is given of a semi-microcombustion method for the estimation of nitrogen in organic compounds. The method is generally applicable and has been uniformly successful. The apparatus and procedure are a combination and simplified modification of several of those previously described in scattered publications.

ISSN:1923-4287    

DOI:10.1139/cjr36b-025

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

By the ebullioscopic method and in benzene solution, saturated fatty acids show, with increasing carbon content, a decreasing degree of association up to lauric acid, after which it remains more or less constant. Unsaturation is shown to decrease the extent to which the molecules of fatty acids of the same carbon content associate. The degree of association of oleic acid in several solvents has also been determined.

ISSN:1923-4287    

DOI:10.1139/cjr36b-026

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

When a value ofKthat allows for the effect of the solute on the dissociation of the solvent is used, raw linseed oil shows normal values for the molecular weight when determined cryoscopically or ebullioscopically in a number of diverse solvents. Similarly, polymerized oils and esters show identical molecular weights in different solvents when determined either cryoscopically or ebullioscopically. The data indicate that polymerized esters of unsaturated fatty acids cannot be assumed to be associated.

ISSN:1923-4287    

DOI:10.1139/cjr36b-027

出版商:NRC Research Press    

年代:1936

数据来源: NRC

摘要:

A modified bromine vapor method for iodine value determination that allows of the determination of substitution is described. For non-conjugated unsaturated oils free from oxidation or polymerization products, values are obtained that are in close agreement with those found by Wijs' method. The unsaturation of conjugated esters can be determined satisfactorily. Owing to substitution, the unsaturation of oxidized or polymerized esters cannot be determined by this method.

ISSN:1923-4287    

DOI:10.1139/cjr36b-028

出版商:NRC Research Press    

年代:1936

数据来源: NRC