| 释义 |
barium Chem.|ˈbɛərɪəm|
Rarely (and obs.) baryum.
[f. bar-yta, -ytes + -ium; cf. soda, sodium. Davy purposely discarded the second syllable of baryta, as in his proposed alumium from alumina, and magnium from magnesia.]
a. A white metallic element, not found native, but as the basis of the alkaline earth baryta. First separated by Sir H. Davy in 1808.
1808Sir H. Davy in Phil. Trans. XCVIII. 346, I shall venture to denominate the metals from the alkaline earths, barium, strontium, calcium, and magnium. 1819[See baria]. 1873Watts Fownes' Chem. 357 Barium occurs as sulphate and carbonate, forming the veinstone in many lead mines.
attrib.1869Roscoe Chem 221 Barium compounds occur somewhat more widely dispersed than those of strontium.
b. Special comb. barium meal, a mixture containing barium sulphate, a white compound that is opaque to X-rays, used in radiological examination of the alimentary tract. So also barium enema, barium swallow.
1913Lancet 31 May 1529/2 Dr. J. Delpratt Harris gave a demonstration of a Barium Meal in a case of Gastroenterostomy. 1930D. A. Rhinehart Roentgenographic Technique xviii. 346 Postero-anterior views of the colon filled with a barium enema. 1940Med. Ann. 507 A patient..was submitted..for a barium enema examination of the colon. 1946Brit. Jrnl. Radiology Mar. 114/2 On examination with a barium swallow and meal it was seen that there was..dilatation..of the œsophagus. 1962Lancet 13 Jan. 67/1 Barium-swallow examinations may fail to demonstrate œsophageal varices. 1966Listener 24 Feb. 273/1 They performed all sorts of tests on me with barium meals. |