ISSN:0021-8979    

DOI:10.1063/1.1714840

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714841

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714842

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714843

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

COLLOIDAL particles present in solutions and suspensions increase the effective viscosity of the solvent. Einstein has presented the theory of this effect valid for spherical particles, and given an equation, deviation between which and experiments being due to either solvation or electric charge of the particles. Elongated particles require a further modification of the formula. The theory is being successfully applied to the study of synthetic fiber molecules, and valuable information as to the shape of the latter can be derived by viscometric measurements on colloidal solutions of such polymers.

ISSN:0021-8979    

DOI:10.1063/1.1714844

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714845

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

Measurements of the magnetic moment of sediments of ferromagnetic particles deposited in a magnetic field show that the particles are magnetically anisotropic. The dependence of this anisotropy on the magnetic field is investigated for sediments prepared under different conditions, and its probable origin discussed.

ISSN:0021-8979    

DOI:10.1063/1.1714834

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

Two methods of indexing powder diffraction patterns of isomorphous substances are presented: the first method depends on matching the logdvalues of two or more isomorphs (dbeing the interplanar spacing of a given reflection); the second method relates the spacing shifts &Dgr;d/dof two isomorphs to the symmetry of the particular crystal system. These methods are made practical by the publication of tabulated powder diffraction data.

ISSN:0021-8979    

DOI:10.1063/1.1714835

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

From photographs, and from the marking on the electrodes, Slepian and Haverstick found that short duration arcs of 25 amperes in gases at a pressure of a few centimeters had apparent current densities at the cathode of less than 100 amperes per cm2. This is in sharp contradiction to the density of several thousand amperes per cm2which seems to be required by generally accepted theories of the cold cathode arc. Similar results have been found up to currents of 5000 amperes, burning for 1/120 sec. with electrodes of various metals in air at less than 10‐cm pressure. Apparent cathode current densities calculated from the observed marking on the electrodes were less than 1000 amperes per cm2. The markings on the electrodes were apparently produced by oxidation only, the energy density developed at the electrodes being insufficient to bring the electrode surface to the melting point in the 1/120 second duration of the arc. The circuit interrupting capacity of these short low current density arcs are found to be not less than that of short arcs at atmospheric pressure.

ISSN:0021-8979    

DOI:10.1063/1.1714836

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714837

出版商:AIP    

年代:1942

数据来源: AIP