ISSN:0021-8871    

DOI:10.1002/jctb.5010170907

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY

摘要:

AbstractThe relative humidities maintained over saturated and unsaturated salt solutions and of some salt hydrate mixtures have been collated from the literature over a wide range of temperature. Results are presented for 38 saturated salt solutions, and details listed for salts which are recommended as suitable for humidity control. The control of humidity in the laboratory by the use of salt solutions is critically discussed.

ISSN:0021-8871    

DOI:10.1002/jctb.5010170901

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY

摘要:

AbstractResults of following the quantities of free Ca(OH)2and of tricalcium silicate (C3S) during the hydration of C3S, and also the influence of the presence of free CaO on this reaction are in accordance with the hypothesis of Stein&Stevels with regard to the hydration of C3S. at the first contact between C3S and water, a surface hydrate, invisible by electron microscope methods, is considered to be formed and to retard the reaction strongly. This hydrate is thought to change into one which retards the hydration reaction less and changes later into a third hydrate, tobermorite gel.

ISSN:0021-8871    

DOI:10.1002/jctb.5010170902

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY

摘要:

AbstractThe application of a wavefront‐shearing optical interferometer to diffusion measurements in aqueous solutions of mono‐, di‐, and tri‐ethanolamines is described. This technique is extremely accurate in determining diffusivities, and the results are compared with measurements made with a Gouy interferometer. The large differences between the experimentally determined diffusion coefficients at infinite dilution and those predicted by existing semi‐empirical equations are shown to be due in part to the inadequacy of these equations, and in part to the hydration of the ethanolamines in solution. It is recommended that, in the use of the semi‐empirical equations, molecular irregularities in solution be allowed for by recalculation of the solute molecular volume on the basis of a hydrat

ISSN:0021-8871    

DOI:10.1002/jctb.5010170903

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY

摘要:

AbstractBenzalacetone was hydrogenated using a Raney nickel catalyst, and various amounts of HCl, NaCl and H3PO4in ethyl alcohol were added to test their inhibiting effect on catalytic activity. In the presence of HCl and H3PO4, Raney nickel lost its catalytic activity, and the rate of hydrogenation was decreased, but NaCl had no effect. While the hydrogenation of the ethylenic bond of benzalacetone was retarded, the decrease in hydrogen uptake by the carbonyl group was affected much more, and the amount of alcohol produced was markedly reduced.

ISSN:0021-8871    

DOI:10.1002/jctb.5010170904

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY

摘要:

AbstractIn the light of the present and previous experimental observations, the discrepancy between the dissociation pressures and the thermodynamic results of the system 6 Mn2O3= 4 Mn3O4+O2is discussed. The degree of fineness and the related lattice defects of the solid phases, the oxygen content of the Mn2O3modification and the sintering of the fine solid material are thought to be causes of such inconsistency. Less probable is the effect of the mutual solubility of α‐Mn2O3and α‐Mn3O4.The thermodynamic results for the association of α‐Mn2O3are given.At given time intervals during a dissociation run, the pressure values are stable and independent of time and can be reached from both directions when it is a matter of small shifts about the equilibrium state. Higher oxygen pressures are attained on combination when dissociation and combination processes are carried out successively in the same run. The difference in pressure decreases with increase of temperature. The results may indicate a hysteresis ph

ISSN:0021-8871    

DOI:10.1002/jctb.5010170905

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY

摘要:

AbstractBulk compressibilities of a series of six linear polymers have been measured at pressures up to 16,000 atmospheres and over the temperature range 21° to 193°. All the polymers exhibited non‐linear pressurevs.change in volume isotherms. In a few cases the polymers exhibited pressure‐induced glass transitions. The coefficient of compressibility at one atmosphere usually increases with increasing temperature. at about 25° most polymers exhibit compressibilities of the order of 10 to 15%. The nature of the observed compressibilities is discussed in relation to the free volume of the

ISSN:0021-8871    

DOI:10.1002/jctb.5010170906

出版商:John Wiley&Sons, Ltd    

年代:1967

数据来源: WILEY