摘要:

Equivalent conductances, viscosities, and densities were determined for solutions equimolar in two of the three salts lithium nitrate, ammonium nitrate, and silver nitrate. The three possible combinations of two salts were each studied at 25 °C and at 35 °C.The observed conductances and viscosities were compared with those of the single salt solutions at the same total ion concentration. The conductances were lower than the mean of the conductances of the single salt solutions. The viscosities were also lower than the mean viscosities.

ISSN:0008-4042    

DOI:10.1139/v58-196

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

It is shown that the change in thermodynamic potential of a solid when elastically strained by the application of the principal stressespx,py, andpzis given by the equationwherevis the volume per unit mass andis the shear strain work done on unit mass of the solid, atTand (px + py + pz)constant, as the relative values ofpx,py, andpzvary, i.e., as the values of the principal stresses vary from their mean.

ISSN:0008-4042    

DOI:10.1139/v58-197

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

Using a microcalorimeter of the Calvet type, measurements have been made of the heats of adsorption of water vapor on microcrystals of sodium chloride, the rate of heat production being followed as a function of time. With crystals of surface areas between 1 and 15 square meters per gram it was found that three distinct processes occurred, in the following order: (1) simple adsorption of water on the surface, (2) decrease in the surface area, and (3) penetration of water into the lattice. During the second stage no adsorption could be detected. On crystals with larger surface areas there was considerable overlapping of the three phenomena, but the general mechanisms appear to be the same.

ISSN:0008-4042    

DOI:10.1139/v58-198

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

not available

ISSN:0008-4042    

DOI:10.1139/v58-199

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

The spectra of nitrobenzenes are discussed in terms of previously proposed hypotheses relating electronic interactions and ultraviolet absorption spectra.

ISSN:0008-4042    

DOI:10.1139/v58-200

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

The electronic spectra of benzaldehydes in the region 220–360 mμ are recorded and discussed in terms of previously stated hypotheses. The formyl group is shown to endow benzene derivatives with spectral properties similar to those of the acetyl group in acetophenones, except that steric interactions are slightly modified.

ISSN:0008-4042    

DOI:10.1139/v58-201

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

A spectral analysis of benzene derivatives in terms of steric and electronic interactions is extended to ring-substituted anilines.

ISSN:0008-4042    

DOI:10.1139/v58-202

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

La synthése de la 4,6,7-triméthoxy- et de la 1-méthyl-4,6,7-triméthoxy-9-xanthone a été réalisée en faisant agir un mélande d'anhydride acétique et d'acide sulfurique sur l'acide 6-(2′-méthoxy)- ou 6-(2′-methoxy-5′-méthylphénoxy)-vératrique. La préparation de ces deux acides a été effectuée en condensant le 6-bromovératrate de méthyle avec le guaїacolate ou l'isocréosolate de potassium en présence de cuivre. La 1-carboxy-4,6,7-triméthoxy-9-xanthone, un produit de dégradation de la cularine, a été obtenue en oxydant la 1-méthyl-4,6,7-triméthoxy-9-xanthone par l'acide chromique en solution dans l'acide éthanoique

ISSN:0008-4042    

DOI:10.1139/v58-203

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

This system illustrates "partial molecular sieve action". Methane has a higher affinity for the sorbent and hence is preferentially sorbed at equilibrium, while nitrogen diffuses through the crystal more rapidly and thus is preferentially taken up during the early stages of sorption. Measurements were made with the pure gases and with mixtures at 0 °and −79.4 °C. The sorption isotherms fit Langmuir equations and the isosteric heats of sorption are essentially independent of concentration. The sorption rates for the pure gases may be characterized by diffusion coefficients,D, calculated in the usual manner assuming the flux of diffusion to be proportional to the concentration gradient. The resultant values forDincrease with increasing sorbate concentration. Diffusion of a mixture may be formally characterized byD's for each component. While that for methane is approximately the same as for methane alone,Dfor nitrogen in mixtures is much larger than for the pure gas and also varies with composition. This, as well as the existence of a temporary maximum in the amount of nitrogen sorbed, may be explained by considering the driving force for diffusion to be the gradient in chemical potential rather than in concentration.

ISSN:0008-4042    

DOI:10.1139/v58-204

出版商:NRC Research Press    

年代:1958

数据来源: NRC

摘要:

The dose-rate, energy, and temperature dependence of the system l0−4 M4,4′-(5-chloro-2-thenylidene)bis[N,N-dimethylaniline], l0−4 Mferrous ammonium sulphate, 0.1 Msodium chloride, and 7 × 10−3 Mhydrochloric acid has been investigated. No energy dependence was observed in the range 0.16 to 2.0 Mev and no dose-rate dependence was observed in the range 4 to 230 rads/minute. However, with dose rates of 400 to 1200 rads/minute, postirradiation dye fading was observed. In the dosage range 0 to 1000 rads this fading is not extremely serious. The system is slightly temperature dependent at temperatures lower than 30 °C and markedly dependent at higher temperatures. Dye yields of samples irradiated at 30 °C were 10% higher than those of samples irradiated at 15° but 33% lower than those of samples irradiated at 45°.

ISSN:0008-4042    

DOI:10.1139/v58-205

出版商:NRC Research Press    

年代:1958

数据来源: NRC