| 释义 |
uranium|jʊˈreɪnɪəm|
[mod.L. (Klaproth, c 1790), f. the name of the planet Uran-us + -ium.]
1. a. A rare, heavy, grayish metallic element, found esp. in pitchblende and uranite. (Now important as fissile material in nuclear reactors and atomic bombs.) Also with following (arabic) numeral, denoting the mass number of the isotope concerned; and with following (usu. Roman) numeral or capital letter denoting an isotope of uranium or one formed by the decay of uranium.
uranium I, uranium 238; uranium II, uranium 234; uranium X or uranium X1, thorium 234 (the decay product of uranium I); uranium X2, metastable protactinium 234 (the decay product of uranium X1); uranium Y, thorium 231 (a decay product of uranium 235); uranium Z, protactinium 234 in its ground state.
In first quot. erron. identified with pitchblende.
1797Encycl. Brit. (ed. 3) XVIII. 691 Uranium, a fossil found..in Saxony, and..in Bohemia, and is, by the miners, called Pechblend. 1805Phil. Trans. XCV. 348 The solution..contained oxide of uranium. 1842E. A. Parnell Chem. Anal. 169 Both the peroxide and protoxide of uranium are precipitated from their solutions by ammonia. 1843Penny Cycl. XXVI. 39/2 Uranium is very combustible;..it burns with a remarkably white and shining light. 1857Miller Elem. Chem., Org. x. §1. 592 Salts of uranium. 1868Watts Dict. Chem. V. 940 Péligot, in 1840, showed that the body previously regarded as metallic uranium was really the protoxide (UO); he likewise obtained the true metal. 1875Vogel Chem. Light xvi. 267 Uranium itself is a rare metal whose combinations play a great part in colouring materials. 1900W. Crookes in Proc. R. Soc. LXVI. 418 The new body must have a name. Until it is more tractable I will call it provisionally UrX—the unknown substance in uranium. 1903Phil. Mag. V. 442 It was shown in 1900 by Sir William Crookes (Proc. Roy. Soc., 1900, vol. lxvi. p. 409) that the activity of uranium to a photographic plate is caused by the presence of a minute amount of a foreign substance to which he gave the name Uranium X. 1911G. N. Antonoff in Ibid. XXII. 425 The period of the new product deduced from the curve is 1·5 days... It is proposed to call the new product uranium Y (UrY). 1912Geiger & Nuttall in Ibid. XXIII. 444 It enables us to calculate the period of ionium and of the second product in uranium (uranium II.) with greater certainty than has hitherto been possible. Uranium I. therefore..emits α particles of range 2·5 cm. in air.. and is followed by another α-ray product, uranium II., which..emits α particles of range 2·9 cm. 1950tr. Hahn's New Atoms 109 The element 93 remains in bulk in solution—free from uranium, uranium X and the fission products. 1950Glasstone Sourcebk. Atomic Energy xiv. 401/2 The non⁓fissionable uranium-238..constitutes over 99·2 per cent of ordinary uranium. 1960W. T. L. Neal in J. C. Collins Radioactive Wastes ii. 25 Reactors are operated for three purposes—for fuel production (e.g. production of plutonium-239 from uranium-238, or uranium-233 from thorium-232), for power production and for research. 1962Newnes Conc. Encycl. Nucl. Energy 659/1 Uranium II, U234, is a decay product of natural uranium, being formed by beta decay of uranium X2 and uranium Z.
b. attrib., esp. in the names of salts, ores, etc., as uranium acetate, uranium fission, uranium fuel, uranium nitrate, uranium-ore, uranium oxide, uranium phosphate, uranium vitriol; also Comb., as uranium-bearing, uranium-prepared; uranium bomb, an atomic bomb in which uranium is the fissile material; uranium hexafluoride, a whitish crystalline hygroscopic compound, UF6, which sublimes at 56°C and is the form in which uranium isotopes are separated by gaseous diffusion; uranium lead, (a) the isotope lead 206, = radium G s.v. radium 1 b; (b) used attrib. (with hyphen) to designate a method of isotopic dating, and the results obtained with it, based upon measurement of the relative amounts in rock of uranium 238 and 235 and of their ultimate decay products lead 206 and 207; uranium series, the series of isotopes produced by the radioactive decay of uranium 238, each member resulting from the decay of the previous one.
Various other examples have appeared in special Dicts., as uranium-bloom, uranium-green, uranium-ochre, uranium-orange, uranium-yellow (1868 Watts' Dict. Chem. s.v.).
1890J. Cagney tr. Jaksch's Clin. Diagn. 269 Uranium acetate or nitrate is added in solution.
1941in M. Gowing Britain & Atomic Energy 1939–1945 (1965) 394 We have now reached the conclusion that it will be possible to make an effective uranium bomb..which would be equivalent as regards destructive effect to 1,800 tons of T.N.T. 1955Times 14 June 6/5 Information appears to be coming to light here which confirms that the so-called hydrogen bomb exploded at Bikini last year was a uranium bomb involving a triple process of fission-fusion-fission. 1964M. Gowing Britain & Atomic Energy 1939–45 i. 38 As war began there was much speculation about Hitler's supposed ‘secret weapon’ and..the uranium bomb was among the candidates for this title.
1942Pollard & Davidson Applied Nucl. Physics x. 187 The answer lies in the discovery of uranium fission by Hahn and Strassman. 1955J. Lindhard in W. Pauli Niels Bohr 193 Through the discovery of uranium fission it became possible to investigate the penetration of highly charged nuclear fragments.
1956A. H. Compton Atomic Quest 321 Uranium fuel must compete economically with such energy sources as coal.
1899Collective Index Trans. & Abstr. Chem. Soc. 1873–1882 629/1 Uranium hexa-fluoride. 1941in M. Gowing Britain & Atomic Energy 1939–45 (1964) 395 Work on a fairly large scale is needed to develop the chemical side for the production in bulk of uranium hexafluoride, the gaseous compound we propose to use [for the manufacture of 235U]. 1971Uranium hexafluoride [see hex n.2]. 1984Times 27 Aug. 1/6 The ship's owners identified the material as uranium hexa⁓fluoride, a radioactive gas.
1914Phil. Mag. XXVIII. 825 The equation for the complete disintegration of uranium is U→8He + Radium G (uranium lead). 1955[see thorium lead s.v. thorium 2]. 1955Bull. Geol. Soc. Amer. LXVI. 1141/1 (heading) Uranium-lead age of the granite. 1977A. Hallam Planet Earth 184/2 Isotopic age measurements by the uranium-lead and rubidium-strontium methods on most meteorites have yielded a solidification age close to 4600 million years.
1873C. H. Ralfe Phys. Chem. 237 The solution of Uranium Nitrate.
1837Dana Min. 372 Pitchblende. Uranius amorphus. Uncleavable Uranium-Ore.
1890J. Cagney tr. Jaksch's Clin. Diagn. 269 A solution of uranium oxide.
1862Catal. Internat. Exhib., Brit. II. No. 3054, Developments of uranium-prepared papers.
1909Chem. News 26 Mar. 146/2 (heading) A new radio-active product of the uranium series. 1973Uranium series [see thorium series s.v. thorium 2].
1850Watts tr. Gmelin's Handbk. Chem. IV. 175 Monosulphate. Found native as Uranium-vitriol.
2. ellipt. A solution of a salt or nitrate of uranium. Chiefly attrib. and Comb.
1878Abney Photogr. 155 Printing with iron and uranium compounds. 1890Anthony's Photogr. Bull. III. 361 The uranium intensifier..in my own practice has proved the simplest and best of all intensifiers. 1892Photogr. Ann. II. 422 Carbutt's Positive Films..are amenable to uranium toning. 1900J. A. Hodges Pract. Enlarging xiii. (ed. 4) 98 The appearance of a uranium-toned print. |