| 释义 |
radium|ˈreɪdɪəm|
[f. L. radius ray, radius: see -ium.]
1. Chem.
a. [a. F. radium (P. Curie et al. 1898, in Compt. Rend. CXXVII. 1217).] A radioactive element, chemically a member of the alkaline earth metals, which occurs in small amounts in uranium ores, notably pitchblende; atomic number 88, symbol Ra.
1899Chem. News 6 Jan. 1/2 These different reasons lead us to believe that the new radio-active substance contains a new element, to which we propose to give the name of radium. 1903Daily Mail 11 Sept. 3/1 All the speakers recognised that the discovery of radium, with its apparent power of emitting heat for ever without diminution, has opened the door to something like a new world of science. 1904Daily Chron. 7 Jan. 5/1 It is quite as good as any other assertion to say that an ounce of radium is worth the British Empire; no more having yet been obtained than about the weight of a lump of sugar. 1909‘O. Henry’ Roads of Destiny xxi. 358 ‘Change the treatment,’ says I... ‘Call a consultation or use radium or smuggle me in some saws or something.’ 1933Bowing & Fricke in O. Glasser Sci. of Radiol. xv. 281 The paramount advantage of the use of radium in medicine..consists in the proved fact that the rays of radium have a selective action on cancer cells. 1950Thorpe's Dict. Appl. Chem. (ed. 4) X. 446/1 The history of radium refining during the 50 years, 1898–1948,..covers the rise of radium from a scientific curiosity to a commodity of almost fabulous value and wide importance, and its subsequent relegation to a minor role following the development of the atomic pile. 1958Daily Express 11 Mar. 7/1 An escape of radium at a hospital led to the dumping of tons of material down a disused pit shaft. 1974Encycl. Brit. Micropædia VIII. 382/1 Metallic radium has high chemical reactivity. It dissolves in water with vigorous evolution of hydrogen.
b. (Followed by capital letter.) Designating substances (mostly radioactive) subsequently identified as isotopes of other elements, which are formed successively in the radioactive series of radium: radium A, polonium 218; radium B, lead 214; radium C, bismuth 214 together with some polonium 214 (radium C1 or radium C′) and thallium 210 (radium C2 or radium C{pp}); radium D, lead 210; radium E, bismuth 210; radium F, polonium 210; radium G, lead 206, the non-radioactive end-product of the series.
The substances now designated radium E and F were in the first instances named radium D1 and E respectively.
1904E. Rutherford in Phil. Mag. VIII. 636 For convenience, the products in the active deposit will be termed Radium A, Radium B and Radium C, respectively. Ibid. 641 Following the nomenclature suggested, radium C gives rise to the β ray product, which will be called Radium D, while radium D changes into the α ray product, which will be called Radium E. 1905― in Nature 9 Feb. 342 In order to avoid confusion, I have called the new radium product ‘radium D1’. If no further intermediate products of radium are brought to light, it would be simpler to call it radium E and to call the α ray product (polonium) radium F. 1905― in Phil. Mag. X. 293 This rayless product will be called radium D. The β ray product which arises from it will be called radium E. The α ray product (previously termed radium E) will be called Radium F. 1910Westm. Gaz. 16 Feb. 4/1 Sir William Ramsay's description..of ‘Radium D’, one of the mysterious products of radium, as ‘rather dull-looking, like lead’. 1911Phil. Mag. XXII. 628 Fajans has suggested that the name radium C2 should be given to the new product of period 1·4 minutes. 1913Nature 28 Aug. 659/2 That radium-G and lead are identical is supported by much indirect evidence, though no direct proof has been advanced. 1933Failla & Quimby in O. Glasser Sci. of Radiol. xiii. 249 In about a month the equilibrium amounts of radon and radium A, B, and C will have accumulated, and the preparation has a maximum beta and gamma ray activity. 1936Discovery July 218/2 The radium E was produced..through the bombardment of bismuth, with deuterons at an energy of 5,500,000 electron volts. 1966R. Oliver Radiation Physics in Radiol. vi. 71 Radium then disintegrates to form radon which is a gas at normal temperature and pressure. There follows a long series of disintegrations through nuclides referred to as radium A (RaA), B, C, C′, C{pp}, D, E, F and G. The last nuclide (radium G) is a stable isotope of lead. 1974Encycl. Brit. Micropædia VIII. 382/1 A sample of radium, sealed to prevent the escape of gaseous radon, reaches radioactive equilibrium in about a month and becomes a powerful source of gamma radiation, due especially to radium C (bismuth-214).
2. A smooth, plain fabric with the sheen of silk (see quots.).
1904Daily Chron. 12 Mar. 8/5 The newest ribbon is radium, and what a future lies before it! 1930Daily Express 6 Oct. 5/2 (Advt.), Radium velvet. Rich quality panne velvet giving a fashionable brilliance for afternoon and evening wear. 1957M. B. Picken Fashion Dict. 269/1 Radium, smooth, pliable lingerie fabric of synthetic yarn in plain weave, with dull finish and natural sheen of silk. 1970R. T. Wilcox Dict. Costume 281/2 Radium, a lustrous, plain, smooth silk or rayon, which has crispness, yet supple, draping quality.
3. attrib. and Comb., as (sense 1) radium atom, radium bromide, radium chloride, radium salt, radium sulphate, radium treatment; (sense 2) radium poplin, radium silk, radium velvet; radium-bearing, radium-coloured adjs.
1903Daily Mail 11 Sept. 3/1 Illustrating the amazing properties of a radium atom. 1926R. W. Lawson tr. Hevesy & Paneth's Man. Radioactivity xxiii. 161 St. Joachimstal in the Erzgebirge is the most important source of radium-bearing ores in Europe.
1904Chem. News 24 June 301/1 As radium bromide yields electrolytic gas, containing an excess of hydrogen, the pressure gradually rose. 1913Med. Ann. 647 Each capsule contains ·0002 mgram radium bromide. 1966P. Astbury tr. G. Amaldi's Nature of Matter iv. 125 Pierre and Marie Curie..had to examine about seven tons of pitch-blende..in order to prepare a single gram of radium bromide.
1902Harper's Mag. Aug. 360/2 M. Curie possesses about two to three hundredths of a gram of chemically pure radium chloride. 1904Daily Chron. 2 Sept. 8/3 A magnificent mantle fully trained and made of radium-coloured taffetas mousseline, the blue, pink, and moonlight shades of which mingle with one another. 1952C. W. Cunnington Eng. Women's Clothing 296 Radium poplin, a silk and wool textile looking like a silk poplin.
1905Kipling Actions & Reactions (1909) 121 An expense of one hundred and seventy-odd pounds..for radium salts and such trifles. 1956J. K. Robertson Radiology Physics xii. 228 When radium needles are used, the dose delivered to the region treated depends on..the amount of absorption by the materials enclosing the radium salt. 1972Barnes & Rees Conc. Textbk. Radiotherapy viii. 178 Radium is prepared as the salt, radium sulphate, and mixed with a suitable filler, it is sealed into thin-walled metal capsules.
1936Discovery Nov. 351/2 Apparatus for radium treatment recently installed at the Hampstead annexe of Westminster Hospital.
1930Radium velvet [see sense 2 above].
b. Special Combs.: radium beam, a beam of gamma radiation from a radium source, used in radiotherapy; radium bomb, a container holding a large quantity of radium and used in radiotherapy as a source of a gamma ray beam; radium burn, a burn caused by over-exposure to radiation from radium; radium clock, a device utilizing the β-rays of radium to charge two electroscopic leaves, which discharge at regular intervals when they diverge sufficiently to touch two earthed metal plates; radium emanation, the radon isotope of atomic weight 222, which is the first product of the radioactive decay of radium; cf. emanation 2 c; radium needle, a needle containing radium which can be inserted into tissue for radiotherapy; radium plaque = plaque 3; radium therapy, radiotherapy using radiation from radium.
1933Jrnl. Amer. Med. Assoc. 12 Aug. 533/2 The work before the radium beam therapy research will be to..discover how far the present limited field of operation for a mass radium unit..may be extended. 1940Ibid. 16 Mar. 999/1 Treatment of carcinoma of the mouth and throat by the radium beam is at least as satisfactory as by surgery or interstitial radium. 1956J. K. Robertson Radiology Physics xii. 227 In radium beam therapy, the source contains several grams of this radioactive element.
1930Brit. Med. Jrnl. 19 July 98/1 An attempt to measure accurately the gamma radiation field, in air, of the radium ‘bomb’ in use at Westminster Hospital annexe. 1952W. M. Levitt Handbk. Radiotherapy iii. 42 It is probable that the radium bomb can do nothing that super-voltage x-ray therapy cannot do at least as well and little that deep x-ray therapy cannot do.
1908Jrnl. Amer. Med. Assoc. 30 May 1871/1 (heading) Radium burns of the skin. 1926R. W. Lawson tr. Hevesy & Paneth's Man. Radioactivity xxv. 211 Radium burns are especially troublesome, because..even if they mend there remains a supersensitiveness of the skin. 1940S. Cade Malignant Dis. & Treatm. by Radium 246 Radium burns of the skin or mucous membrane may take 8 to 10 months to heal.
1905W. Hampson Radium Explained 69 We are now able to understand the action of the radium clock. 1905E. Rutherford Radio-Activity (ed. 2) iv. 123 This ‘radium clock’ should work at a sensibly uniform rate for many years, but..the number of β particles emitted would decrease exponentially with the time, falling to half value in about 1200 years. 1926R. W. Lawson tr. Hevesy & Paneth's Man. Radioactivity xxv. 211 The so-called ‘radium clock’..illustrates how the rays from radium may be utilized indirectly to give rise to motion.
1901Nature 13 June 157/2 The radium emanation..preserved its radiating power for several weeks. 1910Daily Chron. 17 Feb. 3/3 Take the next product, the gas which it is continually giving off, and which is called radium emanation. That can be worked with because it is only half gone in four days. 1946F. E. Zeuner Dating Past x. 318. As radium decays, a gas called radium-emanation is formed which, in turn, emits another atom of helium and thereupon changes into a solid substance, called radium A.
1921Pennsylvania Med. Jrnl. XXIV. 218/1 Radium needles should be inserted directly into the glands. 1959C. L. & J. A. Martin Low Intensity Radium Therapy iii. 33 Low intensity radium needles still seem to provide the best available medium for interstitial therapy. 1960A. Huxley Let. 20 May (1969) 890 For cases like mine, radium needles are now standard procedure at the University of California.
1919Amer. Jrnl. Roentgenology VI. 134/1 It is..a very simple matter to treat a small lesion with a radium plaque. 1962J. Thewlis Encycl. Dict. Physics VI. 171/1 Formerly, radium plaques were used as β-emitters, but these have now been almost completely replaced by applicators containing strontium-90.
1904Med. Electrol. & Radiol. V. 336 (heading) Radiumtherapy. 1905N. Amer. Jrnl. Homœopathy LIII. 720 It would seem wise to postpone judgment as to the worth of radium therapy in dermatology. 1931G. B. Shaw Doctors' Delusions 28 Nobody would dream of excluding radium therapy from the medical curriculum merely because more nonsense has been written about radium than about the philosopher's stone. 1964L. Deighton Funeral in Berlin xxix. 152 Began work as a representative [for] radium therapy machinery 1948. Assigned to Northern Spain as radium therapy equipment salesman 1949. |