| 释义 |
▪ I. sediment, n.|ˈsɛdɪmənt|
Also 6 sedyment (7 sedement).
[a. F. sédiment (16th c. in Hatz.-Darm.), ad. L. sediment-um a settling, sinking down, f. sedēre to sit, settle.]
1. Matter composed of particles which fall by gravitation to the bottom of a liquid.
1547Recorde Judic. Urine 16 b, Al thinges in the water, that be of another matter and substaunce particulerly, then is the urine, as the sedyment or grounde. 1659H. More Immort. Soul ii. ix. 212 The Spirits in the Ventricles of the Brain..will..come to a more course consistency, and settle into some such like moist Sediment as is found at the bottome of the Ventricles. 1676Grew Anat. Plants, Salts of Plants i. (1682) 262 After this white Sedement began to fall to the bottom; there was also gathered on the top, a kind of soft Scum. 1707Curios. in Husb. & Gard. 235 A prodigious Quantity of clear Water must be exhal'd, to get an Ounce of dry Sediments, either saline or earthly. 1743Lond. & Country Brew. ii. (ed. 2) 133 But as to this taking Water out of a River, presently after a Flood..;..while such Water is making its Sediments..the Spirit of it dies. 1837Brewster Magnet. 302 He poured it out carefully, without disturbing such of the iron sediment as still remained. 1857G. Bird's Urin. Deposits (ed. 5) 189 All the sediments I have met with were amorphous.
2. spec. (in Geol. etc.). Earthly or detrital matter deposited by aqueous agency.
1684–5Boyle Hist. Mineral Waters 108 And whether the mud, or Sediment it [sc. Mineral Water] leaves, where it passes or stagnates,..have the same..Medicinal vertues. 1696Whiston Th. Earth ii. (1722) 119 Our present upper Earth is factitious, and the Sediment of the Flood. 1794Sullivan View Nat. I. 44 These beds are..placed over each other, like matters transported by the waters, and deposited in the form of sediment. 1823Buckland Reliq. Diluv. 40 Had they been washed in by a succession of floods we should have had a succession of beds of sediment and stalactite. 1860Tyndall Glac. ii. xxvi. 372 The snow gradually wasted, but it left its sediment behind. 1865Geikie Scenery & Geol. Scot. v. 92 Ordinary marine sediment..sand, gravel, silt, and mud. 1881A. C. Ramsay in Nature 1 Sept. 420/1 Cosmological geology..must go back to times far anterior to the date of the deposition, as common sediments, of the very oldest known metamorphic strata.
3. fig.
1637Sanderson Serm. (1674) II. 64 Those dregs of Uncharitableness that (as the sediments of depraved nature) lurk in the hearts of the most charitable men. 1691–8Norris Pract. Disc. (1707) IV. 44 When the sediment of his troubled spirit was fallen. 1824Byron Juan xv. iv, The ruby glass that shakes within his hand Leaves a sad sediment of Time's worst sand. 1859Dickens T. Two Cities ii. iv, The last sediment of the human stew that had been boiling there all day, was straining off. 1903J. C. Smith in R. Campbell Life 124 The late Bailie Colston, a man best known by the criminal sediment of Edinburgh.
4. attrib. and Comb., as sediment-laden adj.; sediment-collector, a contrivance for preventing the deposition of sediment in a boiler; sediment ring Astr., a ring of rock masses orbiting a planet, regarded as debris from the time of its formation.
1858R. Murray Marine Engines (ed. 3) 234 Sediment collectors, or scale pans. 1886A. Winchell Walks & Talks Geol. Field 51 Down its slopes descend the sediment-laden drainage-waters. 1955Sci. News Let. 22 Jan. 53/1 Dr. Kuiper said that the moon, as it sped away from the earth, plowed through a ‘sediment ring’, a swarm of small satellites moving around the earth. 1970[see planetismal a. and n.].
▪ II. sediment, v.|ˈsɛdɪmənt|
[f. sediment n.]
1. trans. To deposit as sediment.
1859Page Handbk. Geol. Terms s.v. Sediment, Rocks..as shale, clay, sandstone, &c., are termed sedimentary; that is, sedimented from mechanical suspension in water. 1908Chambers's Jrnl. May 396/1 Chemical precipitation was found essential to coagulate the suspended matter and thus enable the greater proportion of it to be sedimented in subsidence basins. 1976Nature 19 Aug. 662/1 We then sedimented the eggs rapidly..in a hand centrifuge.
2. intr.
a. To settle as sediment.
1927Brit. Jrnl. Exper. Path. VIII. 122 In a typical rough culture of enteritidis..the bacteria rapidly sediment to the bottom. 1961Lancet 5 Aug. 322/1 The erythrocytes being allowed to sediment within the syringe. 1971Nature 25 June 527/2 Each preparation sedimented in the analytical ultracentrifuge as a single component with a sedimentation coefficient..of about 9·5S.
b. Of a liquid: to deposit a sediment.
1934in Webster. 1962Luntz & Wright in A. Pirie Lens Metabolism Rel. Cataract 319 Blood was collected..in a mixture of 1% sodium ethylenediamine tetra-acetic acid and 5% dextran..and allowed to sediment. 1978Nature 10 Aug. 611/1 (caption) Heparinated blood was allowed to sediment at room temperature to separate red cells from plasma.
Hence ˈsedimented ppl. a. (also fig.); ˈsedimenting vbl. n. and ppl. a.
1901Lancet 1 June 1533/1 Care will..have to be taken not to overlook the sedimented bacteria which may be lying at the bottom of the tube. 1901Durham in Jrnl. Exper. Med. 15 Jan. 365 In an afternoon several hundred sedimenting preparations can be put up. 1962H. Bloemendal et al. in A. Pirie Lens Metabolism Rel. Cataract 303 More rapidly sedimenting material is observed, but the shape of the corresponding boundary does not allow calculation of the sedimentation coefficient. 1977D. L. Altheide in D. E. Johnson Existential Sociol. iv. 149 These tasks become taken for granted as sedimented knowledge for the members. |