Abstract
LONDON. Physical Society, April 8.—C. L. Fortescue: The characteristics of thermionic rectifiers. Rectifying valves working at low voltages with unsaturated electron currents are discussed. The most economic conditions are briefly dealt with; so far as the limited information with respect to the life of modem valves is concerned, it is probable that long life should be provided for.—B. L. Worsnop: The scattering of X-rays and the J phenomenon. Experiments have been carried out using a ‘balance method’ to obtain the J discontinuity which Barkla found with heterogeneous X-rays scattered by elements of low atomic weight; no such discontinuities have been found. Probably some condition which has not yet been published is required for its production.—Ezer Griffiths: A carbon dioxide measuring instrument based on sound velocity measurement. A quartz crystal is maintained in vibration piezo-electrically, and stationary waves are set up in the gas between the flat surface of the crystal and a movable reflector. The position of the nodes is recognised by the reaction on the quartz crystal, resulting in an increase of the current in the maintaining circuit. The distance from node to node is a measure of the composition of the gaseous mixture, assuming it is composed of two gases which do not react.
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Societies and Academies. Nature 119, 836–839 (1927). https://doi.org/10.1038/119836a0
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DOI: https://doi.org/10.1038/119836a0