摘要:

The effect of various factors that might possibly influence the penetration of soda liquor into spruce wood has been examined. It was found that the rate of delignification was the same irrespective of the size of the sample, from a wood-meal of 0.005 mm. particle size up to a limiting chip thickness of about 10 mm. The density of the wood had no influence on the delignification other than that which would be expected from the higher original lignin content of the more dense wood. The presence of moisture in the chips was without result other than that of diluting the liquor, and the addition of wetting agents for facilitating the penetration rate was without significant effect.

ISSN:1923-4287    

DOI:10.1139/cjr37b-011

出版商:NRC Research Press    

年代:1937

数据来源: NRC

摘要:

The solubility curves and tie-lines at 25 °C. were determined for the systems acetone-water-furfural, water-furfural-ethyl acetate and water-furfural-isoamyl acetate.

ISSN:1923-4287    

DOI:10.1139/cjr37b-012

出版商:NRC Research Press    

年代:1937

数据来源: NRC

摘要:

The base-exchangesandhave been studied with Doucil and various salt solutions. The calcium or barium content of the gel increased as the concentration of the solution decreased. With the more concentrated solutions, the calcium content of the gel increased with increasing temperature; at the same temperature, the calcium content was greater when calcium Doucil replaced sodium Doucil as the initial gel material. Solutions of calcium nitrate and of calcium acetate gave similar results, but these were higher than those obtained with calcium chloride solutions.The exchange reaction is chiefly determined by the relative cationic content of the gel and of the solution, but the actual amount of exchange taking place in a given case is greatly dependent upon the available capacity, which is in turn dependent upon those factors that affect the penetration of the gel. The effects of temperature, of concentration, of the kind of anion and of the kind of gel are thought to be more closely related to the penetration phenomena than to the exchange reaction proper. Although the direction of the effect of concentration is indicated by the equation of Rothmund and Kornfeld, the results are not in quantitative agreement with this equation. The equationis useful for the interpolation of curves obtained at constant anionic normality, especially if the solutions are dilute.

ISSN:1923-4287    

DOI:10.1139/cjr37b-013

出版商:NRC Research Press    

年代:1937

数据来源: NRC

摘要:

Chlorine monoxide undergoes a bromine-sensitized decomposition in light of wave-length 5460 A. The reaction involves short chains and is accompanied by an appreciable dark reaction. The quantum yield is 4.3 at 19 °C. A decrease in pressure occurring near the end of the reaction has been shown to be a photochemical effect, and it is due probably to the bromine-sensitized decomposition of chlorine dioxide formed during the combined light and dark reactions.A mechanism similar to that described by Finkelnburg, Schumacher and Stieger for the unsensitized reaction appears to account for most of the observations.

ISSN:1923-4287    

DOI:10.1139/cjr37b-014

出版商:NRC Research Press    

年代:1937

数据来源: NRC

摘要:

The results obtained by other investigators which have a bearing on the variability of the sulphur content of wool are reviewed briefly. The variability of the sulphur content is discussed on the basis of the various factors that might affect it.The effect of light is appreciable and is a very important one. Any sulphuric acid formed by the action of light, or present owing to some other cause, is difficult to remove by ordinary washing. The effect of boiling water is small. Kempy fibres contain less sulphur than non-kempy fibres of the same wool. The root portions of fibres have a higher sulphur content than the tip portions, while middle portions have intermediate values.The writers' results and those of other investigators which are reproduced do not allow of any definite relation being drawn between sulphur content and fineness.

ISSN:1923-4287    

DOI:10.1139/cjr37b-015

出版商:NRC Research Press    

年代:1937

数据来源: NRC

摘要:

A study of the bromine content in human tissues was made by the method outlined in Part I of this series. In many cases, total halogen determinations were made on the same material. The results suggest the following conclusions:Bromine is a constituent of all human tissues. The amounts found in the same tissue show definite variations.No evidence could be found to support the view that bromine is concerned with pituitary function. The thyroid contains amounts of bromine slightly greater than the amounts found in blood. While functional significance cannot be excluded, it has not been ascertained.No definite relation was found to exist between the distribution of bromine and chlorine in human tissues.

ISSN:1923-4287    

DOI:10.1139/cjr37b-016

出版商:NRC Research Press    

年代:1937

数据来源: NRC