摘要:

The influence of two extreme types of lattice distortions on the X‐ray diagram is demonstrated with the help of a simple one‐dimensional model. In the first type the displacements of the lattice points from their original positions are mutually independent, while in the second type of distortion a similar independence applies to the distance between successive lattice points. This second type gives rise to a broadening of reflexions, while the first does not.The theory is further applied to a special type of lattice, viz. that where two lattice periods occur in statistical succession. This type of lattice may occur in many compounds. It is shown that it gives rise to a single interference at a Bragg angle corresponding to the average period defined by equation (17). In other words, the reflexion shows a continuous shift with varying amounts of the two components in the compound; a result which is, for instance, applicable to several examples of “intramicellar swel

ISSN:0165-0513    

DOI:10.1002/recl.19440631102

出版商:WILEY‐VCH Verlag    

年代:1944

数据来源: WILEY

摘要:

The sedimentation velocity of a long‐chain molecule is greatly increased by the hydrodynamic interaction of its constituent parts. If Kuhn's model of randomly kinked molecules is accepted, the application of a formula obtained by Burgers leads to an expression for the sedimentation velocity which is shown to account for experimental results mentioned in the literature.This hydrodynamic interaction manifests itself in a way‐which illustrates the hydrodynamic meaning of the “undurchspülte Knäuel” assumed by Kuhn and makes his assumption very acceptable. It is emphasized, however, that this interaction is much less effective in the presence of a velocity gradient. This explains the experimental fact that various substances conform to Staudinger's viscosity rule, while at the same time their sedimentation constant is dependent on molecul

ISSN:0165-0513    

DOI:10.1002/recl.19440631103

出版商:WILEY‐VCH Verlag    

年代:1944

数据来源: WILEY

摘要:

AbstractPar bromuration du 2‐acétylaminothiazol, on obtient le 2‐acétylamino‐5‐bromothiazol, dont la structure es

ISSN:0165-0513    

DOI:10.1002/recl.19440631104

出版商:WILEY‐VCH Verlag    

年代:1944

数据来源: WILEY

摘要:

AbstractPour étudier leurs propriétés chimiothérapeutiques, les auteurs ont préparé la 2‐aminothiazol‐5‐sulfonamide et quelques‐uns de ses dérivés. Ils donnent les raisons qui militent en faveur de la structure qu'ils assignent à ces composés, quoique la position du groupe sulfonamide n'ait pas été ét

ISSN:0165-0513    

DOI:10.1002/recl.19440631105

出版商:WILEY‐VCH Verlag    

年代:1944

数据来源: WILEY

ISSN:0165-0513    

DOI:10.1002/recl.19440631101

出版商:WILEY‐VCH Verlag    

年代:1944

数据来源: WILEY