ISSN:0034-6748    

DOI:10.1063/1.1751739

出版商:AIP    

年代:1934

数据来源: AIP

摘要:

The paper presents a description of sensitive and accurate apparatus for measuring the power factor of dielectrics in the frequency range, 60–7,200,000 c.p.s. A Wien bridge with Wagner ground for the direct measurement of both power factor and frequency in the range, 60–10,000 c.p.s. is described. Double shielding of the series resistance arm eliminates errors otherwise inherent in this bridge. The operation of the resonance‐substitution method is discussed for the frequency range, 10,000–7,200,000 c.p.s. Errors due to eddy current losses are eliminated through measurements on loss free liquids. A measuring cell for use with these circuits and also with d.c. measuring circuits is described. Some experimental power factor‐frequency curves illustrating the results obtainable with this apparatus are presented. It is shown that power factor‐frequency data furnish a delicate method of tracing out dispersion phenomena and are useful where the concentration or electric moment of material producing dispersion is small.

ISSN:0034-6748    

DOI:10.1063/1.1751740

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751741

出版商:AIP    

年代:1934

数据来源: AIP

摘要:

A two‐crystal x‐ray spectrometer is described in which wave‐lengths are read directly to 0.01 X.U. from the drum of a precision micrometer screw. Methods of initial adjustment are given in brief outline and as sample results there are shown the close linesL&ggr;2andL&ggr;6of Au(79); and the ``foot'' ofL&agr;1of the same element, with the accompanying satellites, the intensity of which is found to be 0.060 of that ofL&agr;1.

ISSN:0034-6748    

DOI:10.1063/1.1751742

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751743

出版商:AIP    

年代:1934

数据来源: AIP

摘要:

A recorder used for making ink records of low frequency oscillations of a small rotating mirror (such as, for example, a galvanometer mirror) is described: a light beam, modulated in accordance with the mirror vibrations, excites a photoelectric cell, the output of which is sufficiently amplified by a low frequency amplifier to control a pen writer. Since the instrument has been developed for use in conjunction with photographically recording seismographs, the treatment in the article is from a seismological point of view. The frequency response of the recorder alone is calculated, and the method of obtaining it for the entire system of the recorder in combination with a given seismograph is indicated. Records are shown to demonstrate the fidelity of reproduction.

ISSN:0034-6748    

DOI:10.1063/1.1751744

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751745

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751746

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751747

出版商:AIP    

年代:1934

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1751748

出版商:AIP    

年代:1934

数据来源: AIP