摘要:

The action of resazurin in milk is complex and not as yet clearly understood. The various resazurin tests have been proposed as practical tests for estimating bacterial populations in milk before they have emerged from the experimental stage. A significant proportion of results cannot at present be interpreted with the reasonable certainty necessary to justify widespread use of these tests by the dairy industry.

ISSN:1923-4287    

DOI:10.1139/cjr41b-005

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Heating a chrysotile asbestos mill fibre has shown that in the approximate temperature range of 500 to 700 °C. the loss in weight depends on both the time and temperature. At other temperatures the loss is practically independent of the time.Prolonged heating at about 490 °C. expelled about 25%, and at 510 °C. about 50%, of the combined water. Complete dehydration occurred on prolonged heating at about 580 °C., but only above 700 °C. was the loss in weight rapid.On the basis of the data obtained on the resorption of moisture it is suggested that heating for half an hour at 215 °C. would be a more accurate and rapid method for determining free moisture than that commonly employed.

ISSN:1923-4287    

DOI:10.1139/cjr41b-006

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

The first result of heating pure chrysotile asbestos tape, crocidolite (blue) asbestos tape, and glass fibre tape to drive off the adsorbed moisture is an increase in breaking strength.Pure chrysotile tape does not lose strength till a temperature of 370 °C. is exceeded. Prolonged heating at 430 °C. causes a loss in strength of about 20%, at 480 °C. of about 40%. Heating at 540 °C. causes a rapid loss in strength.Crocidolite asbestos tape loses strength more rapidly than chrysotile asbestos tape.Glass fibre tape, though initially stronger than chrysotile tape, is considerably less resistant to heat, beginning to lose strength rapidly at about 250 °C., whereas chrysotile asbestos tape does not suffer any appreciable decrease in strength till a temperature of 400 °C. is exceeded.

ISSN:1923-4287    

DOI:10.1139/cjr41b-007

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

The quantitative distribution of pectic substances in raw cotton has been studied. A new method for the removal of cuticle pectin has been utilized.A combination of this method with analysis for α-cellulose has shown that the non-cellulosic material in undamaged cotton appears to be present in the form of pectin.In direct support of recent work carried out by Harris and co-workers (5, 6), and in contrast to that published by Farr (3), it has been found that reduction of pectin content from 1.18 to 0.12% resulted in a change of fluidity from 1.93 to 2.08, whereas treatment with hydrochloric acid raised the fluidity to 25.8.It is suggested that there is no essential chemical difference between pectin in the cuticle surrounding the fibre and that distributed throughout the fibre.

ISSN:1923-4287    

DOI:10.1139/cjr41b-008

出版商:NRC Research Press    

年代:1941

数据来源: NRC