ISSN:0021-8979    

DOI:10.1063/1.1714795

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714797

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714796

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714798

出版商:AIP    

年代:1942

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1714799

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

The calculation of the settlement and bending of an elastic slab resting on a consolidating foundation under the action of a load concentrated on a line. Two cases are considered: first, when the slab is perfectly pervious to water, and second, when it is impervious. The problem is two‐dimensional.

ISSN:0021-8979    

DOI:10.1063/1.1714800

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

The temperature scales have been determined for well‐degassed specimens of the iron group and from these the emissivity for &lgr; = 0.667&mgr; is calculated. Over the range of temperatures covered the emissivity is nearly a constant except at theA3point in iron where there is a sudden change.

ISSN:0021-8979    

DOI:10.1063/1.1714801

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

It has been proposed by P. Bo¨ning that the curve of the rise of continuous voltage due to the residual charge of a capacitor may be used for computation of the dielectric loss under alternating potential. The proposal has been examined in experiments on two types of capacitor, one with impregnated paper and the other with glass as dielectric. A reasonable agreement between measured and computed values was found for the glass capacitor. A wide divergence was found for each of the two impregnated paper capacitors and grounds are offered for the conclusion that the Bo¨ning proposal is not sufficient for certain types of dielectrics.

ISSN:0021-8979    

DOI:10.1063/1.1714802

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

A method is suggested for the construction of electrostatic electron lenses by building equipotential surfaces whose position in space is calculated from an assumed axial potential. The calculations are carried through for examples of symmetrical and immersion lenses. The symmetrical lens chosen is the well‐known one with minimum spherical aberration represented by an axial potentialV(z) =V0+Aexp (−Bz2) and it is shown that this lens can actually be constructed. An axial potential formed by a sum of two exponential terms is found, for suitable values of the constants, to reduce the spherical aberration to less than one‐half that of the above symmetrical lens. An expression is proposed for the immersion lens with minimum spherical aberration. The aberration for this lens is approximately one‐half that of the above symmetrical lens. It is shown that the usual formula for the focal length of a strong lens is merely the first term in an infinite series and that serious inaccuracies occur by not considering further terms.

ISSN:0021-8979    

DOI:10.1063/1.1714803

出版商:AIP    

年代:1942

数据来源: AIP

摘要:

This paper constitutes the author's answer to some adverse criticisms by John T. Burwell, Jr., of an earlier paper having the same title and reporting evidence for the assumption of liquid slip at the surface of a solid in motion through a viscous liquid. The importance of the results contained in the earlier paper to viscosimetry by the rolling‐ball method is emphasized. This relation exists because the author's apparatus was essentially a rolling‐ball viscosimeter. References are given to independent studies by other investigators which also support the hypothesis of liquid slip. The possibility of the phenomenon's being apparent, only, is brought out by presenting two other interpretations of the author's observations. A new and more accurate method for converting time of roll into viscosity of the liquid than the current graphical one is presented for the rolling‐ball viscosimeter, together with an apparent reason for believing that the calibration curve of this viscosimeter may not always be independent of pressure. The author's reasons for considering this new source of error in the use of the rolling‐ball apparatus for high pressure viscosimetry to be actually non‐existent are given. And finally the author describes an original method for checking the validity of the hypothesis of liquid slip in the case of the rolling‐ball viscosimeter that is entirely different from the method he used in his earlier paper.

ISSN:0021-8979    

DOI:10.1063/1.1714804

出版商:AIP    

年代:1942

数据来源: AIP