| 释义 |
conductivity Physics.|kɒndʌkˈtɪvɪtɪ|
[f. conductive + -ity: cf. activity, nativity, etc.]
1. a. Conductive quality; power of conducting heat, electricity, etc.; esp. with reference to its degree.
1837Whewell Hist. Induct. Sc. (1857) II. 382 Modified by the conductivity or conducting power. 1863Tyndall Heat ix. 237 The melting distance furnished a measure of the conductivity of the bar. 1881Nature No. 620. 465 Crystalline media possessing different conductivities in different directions.
b. Physiol. The property of nervous and muscular tissue by which it conducts an impulse.
1881S. P. Thompson Electr. & Mag. iii. 187 Little is..yet known of the conditions of conductivity of the matter of the nerves. 1903Lancet 18 Apr. 1089 When a nerve is divided it will lose its motor conductivity only after the lapse of some time. 1965Schade & Ford Basic Neurol. ii. ii. 180 Nerve and muscle cells..possess two highly distinctive properties: excitability and conductivity.
2. attrib.
1876Preece & Sivewright Telegraphy 267 The wire resistance or conductivity test is obtained by the differential galvanometer, or by Wheatstone's Bridge. 1909Cent. Dict. Suppl., Conductivity water, water specially purified for use in measuring the electrical conductivity of solutions. 1924S. R. Roget Dict. Electr. Terms 47/1 Conductivity bridge, a form of Wheatstone's Bridge used for the comparison of low resistances. 1937Discovery Sept. 284/2 ‘Conductivity water’ —so called, we believe without irony, because it is one of the most perfect electrically insulating media known. 1959H. Barnes Oceanography iii. 121 Resistance thermometers and thermistors have been used for temperature measurement and conductivity cells for salinity. 1961New Scientist 26 Oct. 237/2 Ultra-pure or conductivity water was, until a few years ago, a substance made in small quantities by multiple distillation..mainly for use in research laboratories. |