| 释义 |
discontinuity|dɪsˌkɒntɪˈnjuːɪtɪ|
[f. med.L. type *discontinuitās, f. discontinu-us: see next and -ity. Cf. F. discontinuité (1775 in Hatz.-Darm.).]
1. a. The quality or state of being discontinuous; want or failure of continuity or uninterrupted sequence; interrupted condition.
1570Dee Math. Pref. 35 They will not be extended, to discontinuitie. 1626Bacon Sylva §846 The Second is the Stronger or Weaker Appetite, in Bodies, to Continuitie, and to flie Discontinuitie. 1733Cheyne Eng. Malady i. x. §4 (1734) 97 Nature seems only to have provided proper Juices to fill up the Discontinuity [in wounds]. 1874L. Stephen Hours in Library (1892) I. ix. 329 He passes from one conception to the other without the smallest consciousness of any discontinuity. 1893J. Pulsford Loyalty to Christ II. 377 We are at the foot of the ladder, and they at the top; but they know there is no discontinuity between lowest and highest.
b. with a and pl. A break or gap in a structure.
1794Sullivan View Nat. II. 413 The spots may also be..temporary holes, or discontinuities in the luminous meteor. 1835R. H. Froude Rem. (1838) I. 408, I see such jumps and discontinuities as make me despair of ever being intelligible.
c. spec. in Math. said of a function or its variation: see discontinuous.
2. attrib., as discontinuity layer, a layer of water in a lake or the sea in which the temperature changes rapidly with depth from that of the water above it to that of the water below; a thermocline separating an epilimnion from a hypolimnion.
1911E. M. Wedderburn in Trans. R. Soc. Edin. XLVII. 625 Attention has been drawn to the very rapid temperature changes which are found at the discontinuity layer. 1931Discovery June 199/2 In general the presence of the ‘discontinuity layer’ tends to prevent the free mixing of the layers [of water in the sea]. 1942P. M. Jenkin in Jrnl. Animal Ecol. XI. 252 The term ‘Discontinuity Layer’ is revived to cover the layer of very variable thickness in which there is a sufficient temperature gradient to impede mixing of the epilimnion with the cool hypolimnion below. 1964Oceanogr. & Marine Biol. II. 125 At depths of hundreds of metres, perhaps below the discontinuity layer, there is a decline to 20–35% of surface mass. |