释义 |
McLeod|məˈklaʊd| Also erron. Macleod. [Name of Herbert McLeod (1841–1923), English scientist, who invented the instrument in 1874 (Phil. Mag. XLVIII. 110).] McLeod gauge: a type of mercury-in-glass manometer for the absolute measurement of low pressures, in which a fixed large volume of the gas to be measured is compressed by the mercury into a small volume and the resulting pressure found from the height of the column of mercury it supports, the desired pressure then being obtained by multiplying this by the ratio of the smaller to the larger volume in accordance with Boyle's law.
1880J. E. H. Gordon Physical Treat. Electr. & Magn. II. xxxv. 83 The apparatus is in connection with a McLeod gauge, by means of which pressures to 0·00005 millim. can be determined. 1923Proc. Cambr. Philos. Soc. XXI. 505 The residual pressure of the gas in the box was measured by a Macleod gauge. 1971Sci. Amer. Aug. 114/2 Although the McLeod gauge indicates absolute pressure and is universally used for calibrating other instruments, it is inconvenient to operate. |