| 释义 |
buncher|ˈbʌntʃə(r)|
[f. bunch n.1 or v.2 + -er1.]
1. One who or that which bunches; spec. a machine for forming bunches or collecting things in bunches.
1881Instr. Census Clerks (1885) 74 Straw Plait Buncher. 1909Webster s.v., An asparagus buncher. 1921Dict. Occup. Terms (1927) §399 Buncher, yarn buncher; (i) ties several hanks of yarn into bunches, in readiness for succeeding processes, bleaching, etc.; (ii) [= ] crofter. 1930C. S. Johnson Negro in Amer. Civilization (1931) v. 64 The lowest median weekly earners were..Tobacco bunchers $1.85. 1939M. Spring Rice Working-Class Wives vii. 164 She worked as a ‘buncher’ in flower gardens.
2. A device that modulates a beam of charged particles and causes them to collect together in ‘bunches’ or groups. Also attrib.
1939R. H. & S. F. Varian in Jrnl. Appl. Physics X. 324/1 The rhumbatron in which the electrons are given their first modulation of speed is called the ‘buncher’, and the one into which the bunches ‘break’ is called the ‘catcher’. 1948J. B. H. Kuper in D. R. Hamilton et al. Klystrons & Microwave Triodes i. 11 The velocity of each electron depends on the instant at which it crossed the buncher gap. 1955Science CXXII. 1131/3 The ion beam passes through the buncher, which applies a 24-megacycle ripple of 5 to 7 kev to the beam. 1962Livingston & Blewett Particle Accelerators x. 333 The buncher..is merely a section of accelerator in which the phase velocity is matched to the particle velocity. |