| 释义 |
‖ separatrix|sɛpəˈreɪtrɪks|
Pl. separatrices |-trɪsiːz|.
[late L., fem. agent-n. f. sēparāre to separate.
The feminine is in apposition with līnea line, understood.]
†1.
a. The mark (originally L, later I), formerly used to separate the figures representing decimals from those representing integers; now superseded by the decimal point.
b. (See quot. 1771). Obs.
1660J. Moore Arith. 11 But the best and most distinct way of distinguishing them [sc. Decimals] is by a rectangular line after the place of the unit, called Seperatrix. Ibid. 13 Therefore in writing of decimall parts let the seperatrix be always used. 1771Luckombe Hist. Printing 286 The Separatrix, or rule between the Numerator and Denominator [of fractions].
2. Proof-correction. (See quot.)
1892A. Oldfield Man. Typog. iii, A wrong letter is noted by a stroke being drawn through and the proper letter written on the margin with a stroke after it. This stroke is placed after all corrections to keep the various marks separate. It is sometimes called the separatrix.
3. The line separating light and shade on a partly illuminated surface. Cf. terminator 2.
a1912In recent Dicts.
4. Physics. A boundary between regions having differing configurations of magnetic lines of force.
1956Proc. CERN Symp. High Energy Accelerators I. 50/1 We see in fig. 3 the region of stability or ‘bucket’ within which particles execute stable phase oscillations... The bucket boundary, or separatrix is given by eq. (43). Ibid. 54/2 The region between the two separatrices. 1979Sci. Amer. Aug. 44 (caption) The tokamak..is equipped with a magnetic divertor, an arrangement in which a magnetic-field separatrix is employed to prevent impurity ions from entering the main plasma column. |