| 释义 |
fractionate, v.|ˈfrækʃəneɪt|
[f. fraction + -ate3.]
1. a. trans. To separate (a mixture) by distillation or otherwise into portions of differing properties. Hence ˈfractionated ppl. a.
1867W. R. Bowditch Coal Gas 5 These heavy oils were obtained by passing the gas over carefully fractionated pure light coal oils. 1894Nature 23 Aug. 410/2 By fractionating Russian petroleum the author had obtained hydrocarbons [etc.].
b. gen. = fractionalize v.
1961in Webster. 1963C. D. Simak They walked like Men xxvi. 155 Might there not be no more than a single one of them, with that one fractionated into units the size of bowling balls? 1965Listener 12 Aug. 233/2 We spend much of our time fractionating living matter. We break it up with sonic oscillations..or by chilling it in solid carbon dioxide and hitting it with a hammer. 1970Sci. Jrnl. Apr. 5/1 Pollution matters beat even space activities for the extent to which they are fractionated between different departments—no less than 12 are involved.
2. intr. To break up into fractions.
1957G. E. Hutchinson Treat. Limnol. I. viii. 543 If the drop fractionates, small daughter drops may be carried to the top of the cloud in an updraft.
Hence ˈfractionating ppl. a. and vbl. n.; fractionating column, a long vertical chamber for fractionating liquids in which vapour from a still passes upwards to a condenser and mixes intimately with falling condensate on the way, so becoming enriched in the lower-boiling fractions.
1908Jrnl. Chem. Soc. XCIV. ii. 17 (heading) A Fractionating Column... A condenser is provided inside the top of the..apparatus, and the distilled liquid is collected at the lower part, being returned to the distillation flask or run off as desired. 1922C. S. Robinson Elem. Fract. Distill. iii. 17 The second general method by which fractionating can be obtained, is fractional condensation. 1952Smith & Stinson Fuels & Combustion i. 22 The vapors are passed into the fractionating column where the oil is separated into several fractions. 1970R. M. E. Diamant Appl. Chem. Engineers (ed. 2) xiv. 248 The degree of separation of the liquid into upper and lower fractions depends upon the number of plates or the length of the fractionating column. |