摘要:

Besides a small quantity of nicotine, four alkaloids have been isolated fromLycopodium tristachyumPursh. One of these, lycopodine, has been described previously. The remaining three bases appear to be new. They are alkaloid L13 (C16H25ON) also found inL.obscurum, alkaloid L14 (C16H25N), and alkaloid L15 (C20H31O4N).

ISSN:1923-4287    

DOI:10.1139/cjr44b-001

出版商:NRC Research Press    

年代:1944

数据来源: NRC

摘要:

This paper presents values of the temperature coefficient of the diffusion constant of copper in aqueous solutions of sulphuric acid containing copper sulphate, for the range 10° to 25 °C. and four acid concentrations. The work is based on the Mathematical Theory of the Changes of Concentration at the Electrode, formulated by Rosebrugh and Miller. Evidence is presented supporting the choice of a new point on the oscillograph potential curve for the measurement oft. The values ofK, thus obtained, at 18 °C. are in agreement with those of Cole and Gordon, who used the method of Northrop and Anson. The values ofKat 10 °C. calculated from those at 25 °C. by means of viscosity data are in agreement with the values obtained by experiment.

ISSN:1923-4287    

DOI:10.1139/cjr44b-002

出版商:NRC Research Press    

年代:1944

数据来源: NRC

摘要:

The equilibrium sedimentation volumes of sodium soaps in suspension in mineral oils have been measured. The sedimentation volume increases greatly with decrease in viscosity index of the oil. Flow–pressure relations, determined with a torsional viscosimeter, show that suspensions with large sedimentation volumes possess rigidity, whereas the flow is Newtonian in suspensions having small sedimentation volumes. Variation in sedimentation volume is therefore caused by difference in the tendency toward agglomeration or attraction between particles, leading to the formation of branched chains and scaffolding structures, with consequently greater sedimentation volumes.

ISSN:1923-4287    

DOI:10.1139/cjr44b-003

出版商:NRC Research Press    

年代:1944

数据来源: NRC