| 释义 |
‖ rubidium|ruːˈbɪdɪəm|
[f. L. rubid-us red, in allusion to the two red lines in its spectrum: coined in Ger. by Bunsen in Ann. d. Chem. (1861) CXIX. 107.]
1. A soft silvery-coloured metal belonging to the group which includes cæsium, lithium, potassium, and sodium. Atomic number 37; symbol Rb.
1861H. E. Roscoe in Proc. R. Inst. III. 326 A few days ago the speaker received a letter from Bunsen, which contains the following most interesting information:—‘The substance which I sent you as impure tartrate of Cæsium contains a second new alkaline metal... I propose to call the new metal ‘Rubidium’.’ 1861Chem. News 27 July 44/2 Both rubidium and cæsium, the two alkali metals recently discovered by means of spectrum analysis, have a great chemical similarity to potassium. 1862Timbs Year-bk. of Facts 188 Cæsium and Rubidium. 1868Watts Dict. Chem. s.v., Rubidium is a white metal, with a tinge of yellow, and a silvery lustre. 1885G. L. Goodale Physiol. Bot. 256 Cæsium and Rubidium have been detected by the spectroscope in minute amounts in many plants. 1912J. W. Mellor Mod. Inorg. Chem. xix. 359 Metallic rubidium is prepared by heating an intimate mixture of the carbonate with finely divided carbon. 1946Nature 2 Mar. 269/1 Minerals richest in rubidium are the lithia micas (lepidolites) which quite frequently contain as much as 2–3 per cent Rb2O. 1950N. V. Sidgwick Chem. Elements I. 65 Rubidium and caesium catch fire at once on exposure to air. 1974Encycl. Brit. Micropædia VIII. 705/3 Rubidium, because of its electropositiveness, is second only to cesium as a proposed working fluid in plasma propulsion for deep-space probes.
2. attrib. and Comb.
1862Phil. Mag. XXIV. 46 (heading) On the preparation of the rubidium compounds. 1911Encycl. Brit. XXIII. 809/1 The rubidium salts are generally colourless, mostly soluble in water and isomorphous with the corresponding potassium salts. 1950F. E. Zeuner Dating Past (ed. 2) x. 334 Other minerals like hydrothermal microclines, pollucite, and rubidium-rich varieties of muscovite, may in due course become important. 1950Thorpe's Dict. Appl. Chem. (ed. 4) X. 637/2 Rubidium Sulphate, Rb2SO4, forms rhombic crystals. 1962F. I. Ordway et al. Basic Astronautics iv. 127 A rubidium-vapor magnetometer to measure magnetic fields in space. 1971I. G. Gass et al. Understanding Earth ii. 44/2 A small amount [of strontium] is usually also incorporated into calcium-poor, rubidium-bearing potassium minerals. 1977Broadcast 13 June 6/3 The MSF time signals are derived from what is loosely described as an atomic pendulum but is more correctly known as a rubidium vapour oscillation.
b. Special Comb.: rubidium-strontium, used attrib. to denote a method of isotopic dating, or results obtained from it, based upon measurement of the relative amounts in rock of rubidium 87 and its beta decay product, strontium 87.
[1946Nature 2 Mar. 269/1 By means of this standard, Rb/Sr ratios of five samples of lepidolite and one of pollucite were determined spectrochemically.., the resultant ages being as follows.] 1950F. E. Zeuner Dating Past (ed. 2) x. 334 Minerals suitable for the rubidium/strontium method must be rich in Rb and free from non⁓radiogenic Sr. 1961Times 25 Apr. 2/6 The Department..is at present using both the potassium-argon and rubidium-strontium methods. 1977A. Hallam Planet Earth 184/2 Rubidium-strontium and uranium-lead measurements conclusively show that all these rocks were formed between about 3700 and 3800 million years ago. |