摘要:

The addition of an auxiliary quartz crystal to the usual composite piezoelectric resonator provides a convenient strain gauge, which simplifies the measurement procedure and permits the evaluation of amplitude dependent decrements over a wide range of strain amplitudes. A unique feature of the new procedure is that virtuallyinstantaneousvalues of the decrement are obtained, thus bringing transient internal friction phenomena under observation. Mechanical resonance frequencies may be precisely determined for high as well as low decrement specimens. The numerical evaluation of terms is carried out for a recommended driver‐gauge construction of 18.5° X‐cut quartz bars.

ISSN:0034-6748    

DOI:10.1063/1.1745981

出版商:AIP    

年代:1951

数据来源: AIP

摘要:

Integrals for the calculation of the solid angle of a plane disk in respect to the window of an end‐window Geiger‐Mu¨ller tube have been derived. Numerical values for a window diameter of 30 mm have been computed.

ISSN:0034-6748    

DOI:10.1063/1.1745982

出版商:AIP    

年代:1951

数据来源: AIP

摘要:

A circuit capable of measuring alternating current potentials up to 1000 microvolts with a precision of 0.01 microvolt has been devised and applied to the measurement of the galvanomagnetic coefficients of semiconductors and metals. The circuit consists essentially of a peaked amplifier applied to the out‐of‐balance signal between an alternating current potentiometer and the potential being measured. The galvanomagnetic coefficients are so related to the potentials that the entire measurement becomes independent of the current. As an example of the results obtainable, data are given to show the variations of the Hall and magneto‐resistivity coefficients during the high temperature graphitization of index rod. The precision of the final data is of the order of one‐quarter percent.

ISSN:0034-6748    

DOI:10.1063/1.1745983

出版商:AIP    

年代:1951

数据来源: AIP

摘要:

A large beta‐ray spectrometer based on the theory worked out by Siegbahn, Svartholm, and others has been constructed. The magnet design is unique in that the return path in iron for the gap flux is provided by a circumferential yoke rather than by an axial core. The mean radius of the electron orbits isr0=30 cm and the maximum acceptable solid angle with present diaphragms is 0.8 percent of a sphere. Construction is discussed and data are presented to show the resolution to be approximately 0.4 percent under these conditions.

ISSN:0034-6748    

DOI:10.1063/1.1745984

出版商:AIP    

年代:1951

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1745985

出版商:AIP    

年代:1951

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1745987

出版商:AIP    

年代:1951

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1745988

出版商:AIP    

年代:1951

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1745989

出版商:AIP    

年代:1951

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1745990

出版商:AIP    

年代:1951

数据来源: AIP

ISSN:0034-6748    

DOI:10.1063/1.1745992

出版商:AIP    

年代:1951

数据来源: AIP