摘要:

This paper describes an improved apparatus for the determination of γ =Cp/Cv, the ratio of the specific heat at constant pressure to the specific heat at constant volume for a gas. With this apparatus, γ is determined by the resonance method of Clark and Katz. The new apparatus is constructed of stainless steel and is designed to withstand pressures up to 100 atm. This new apparatus is more compact and can be used with corrosive gases. Provision is made for the control and accurate measurement of the temperature of the enclosed gas over a wide range of temperatures. An electronic counter which will measure time intervals, in units of 10 μsec., from 100 μsec. to several seconds in length is described in Section B. An unknown frequency may be determined by measuring the time interval in which a preselected number of cycles occurs. The accuracy is such that frequencies may be measured to within approximately 1 part in 105. The circuit for a variable frequency transitron oscillator with an output of 30 w. in a range of 15 to 250 c.p.s. is shown. The stability of the oscillator is such that the frequency may easily be maintained within 1 part in 10,000 for long periods, and with care in temperature control and choice of electrode voltages much greater stabilities may be obtained.

ISSN:1923-4287    

DOI:10.1139/cjr49a-004

出版商:NRC Research Press    

年代:1949

数据来源: NRC

摘要:

Carbon dioxide, nitrous oxide, and methane have been carefully purified and the variation of γ with pressure measured. The results when extrapolated to zero pressure give values of γ0which are in agreement with those obtained by spectroscopic methods. Agreement in each case is better than 0.10%.

ISSN:1923-4287    

DOI:10.1139/cjr49a-005

出版商:NRC Research Press    

年代:1949

数据来源: NRC

摘要:

This paper describes a device that was developed to give a continuous record of the intensity of auroral radiations from the zenithal sky. Detection is by means of the multiplier phototube, R C A type 1P21. A null method of recording is used, the light flux reaching the phototube being kept to a constant value by moving a neutral, wedge filter in front of the phototube. A simple servo-mechanism is used for this purpose. A pen attached to the filter traces a record of the changes of auroral intensity on a clock-driven chart.

ISSN:1923-4287    

DOI:10.1139/cjr49a-006

出版商:NRC Research Press    

年代:1949

数据来源: NRC

摘要:

Methods of determining meteor velocities from single-station observations are discussed. Where three-station observations are available both the velocity and the elements of the meteor's path through the atmosphere can be computed in favorable cases. These methods are applied to a selected daytime meteor, recorded by the three radar stations at 17h59m48sE.S.T., Aug. 4, 1948. The following elements of the meteor's path have been obtained from the radar data:—Apparent geocentric velocity    35.0 ± 0.4 km. per sec.True bearing of apparent radiant    074° ± 2°Elevation of apparent radiant    2° ± 2°Total radar path length    270 km.Height above sea level    108 − 104 km.These values lead to an orbit similar to one of the short-period comets, with these elements:—Semi-major axis    a    2.66Eccentricity    e    0.87Angle node to perihelion    ω    294°.9Longitude of node        132°.4Inclination    i    33°.6Period    P    4.33 years

ISSN:1923-4287    

DOI:10.1139/cjr49a-007

出版商:NRC Research Press    

年代:1949

数据来源: NRC