ISSN:0021-8979    

DOI:10.1063/1.1710363

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1710364

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1710365

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

Time lag measurements are described which were made with a light chopper on a gas‐filled cell of special design. The resulting responsevs.frequency characteristic exhibits the resonance oscillations predicted from theory and calculation of the lag from the positive ion mobility agrees with that determined from this curve. The construction of the cell is such that secondary emission and disintegration of the cathode by ion bombardment are eliminated even at high values of gas amplification.

ISSN:0021-8979    

DOI:10.1063/1.1710366

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

General expressions are derived for the currents which flow in the external circuit connecting a system of conductors when a point charge is moving among the conductors. The results are applied to obtain explicit expressions for several cases of practical interest.

ISSN:0021-8979    

DOI:10.1063/1.1710367

出版商:AIP    

年代:1938

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1710368

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

Creep in metals under constant load indicates that plastic deformation depends on the duration as well as the magnitude of the compressive force. The dependence of deformation on duration is significant in the lead crushers used in measuring pressures. Static compression tests on lead, extending over 30‐minute periods, and under various loads up to 109 kg have been conducted. The dependence of deformation on duration is found to be great under the higher loads, and much greater than the dependence in the case of copper and aluminum, on which comparative tests were made. The deformation‐compression‐time relation is found to be approximately linear under constant pressure. The present data are in agreement with the results of Bogomolov and Kunin on lead for pressures in a higher range. However, the law derived by them does not hold in the pressure‐range of the present tests.

ISSN:0021-8979    

DOI:10.1063/1.1710369

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

Attempts at measurement of the magnetic properties of ferromagnetic materials at very low flux densities showed inconsistencies which were attributed either to errors in methods or to some behavior of the material. Check tests, using the same procedure in each case, eliminated the first supposition. The results of this investigation show that, with a steel of medium silicon content tested at 10 gausses over a period of 24 hours, there exists a 5 to 15 percent decrease in permeability. On the average, 50 to 60 percent of this drift occurred within one hour after demagnetization and none after 24 hours.

ISSN:0021-8979    

DOI:10.1063/1.1710370

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

The theory of the use of certain shapes of ``hohlraums'' as electrical resonators is developed. In many respects they are equivalent to lumped constant circuits with properly chosen circuit constants. Suitable values for these circuit constants are found. The theory of coupling onto these hohlraum types of resonators is developed approximately.

ISSN:0021-8979    

DOI:10.1063/1.1710371

出版商:AIP    

年代:1938

数据来源: AIP

摘要:

1. A method has been devised for measuring the electrical conductivity of single crystals at elevated temperatures and at field strengths below 3 volts per mm. 2. The conductivities of single crystals of quartz, periclase, and corundum have been measured by this method over a temperature range of 600° to 1400°C, in equilibrium with air. 3. The increase of conductivity with temperature follows a single exponential relation in all cases, throughout the temperature range covered. Experimental curves and a table of interpolated values are given.

ISSN:0021-8979    

DOI:10.1063/1.1710373

出版商:AIP    

年代:1938

数据来源: AIP