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VARIATION WITH TEMPERATURE OF THE PIEZOELECTRIC EFFECT IN QUARTZ |
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Canadian Journal of Research,
Volume 14a,
Issue 3,
1936,
Page 57-65
Arnold Pitt,
D. W. R. McKinley,
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PDF (489KB)
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摘要:
As a result of some previous experiments there were indications that the elastic vibrations set up in quartz showed an anomalous property at the temperature of liquid helium. In order to decide this point, experiments were carried out on the piezoelectric activity of quartz at progressively lower temperatures until that of liquid helium was reached. Although a decrease in this activity of only 1% had been observed by others working over the range from room temperature to liquid hydrogen temperatures, the present experiments show a total decrease of 12% at the temperature of liquid helium. Two methods were used, a statical method employed where the temperature could be held constant, and a dynamical method to ascertain the temperature at which any marked change in activity would just become evident. Results by the dynamical method indicate that a sudden decrease in activity occurs at about 5° K. In addition, the dynamical method was extended to higher temperatures, so as to include in this paper values of the piezoelectric activity of quartz from 4° K. to 813° K.
ISSN:1923-4287
DOI:10.1139/cjr36a-007
出版商:NRC Research Press
年代:1936
数据来源: NRC
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PROPAGATION AND RESONANCE OF COMPOSITE WAVES IN PRISMATIC RODS |
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Canadian Journal of Research,
Volume 14a,
Issue 3,
1936,
Page 66-70
R. Ruedy,
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PDF (222KB)
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摘要:
By taking into account the three main terms of the equation of motion of the prismatic rod, there is obtained for the frequency a cubic equation which is in good agreement with the experimental results when the thickness of the rod is not negligible compared with its length but does not exceed about one-fifth of the length. It corresponds to the equation obtained for a system with three degrees of freedom.For a composite vibration consisting of a wave of dilatation and a wave of distortion in the direction of the smallest dimension of the rod, and waves of dilatation in the two other directions, the equations of motion combined with some of the boundary conditions yield another cubic equation for the resonance frequencies.
ISSN:1923-4287
DOI:10.1139/cjr36a-008
出版商:NRC Research Press
年代:1936
数据来源: NRC
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