| 释义 |
polarograph Chem.|pəʊˈlɑːrəʊ-, ˈpəʊlərəʊgrɑːf, -græf|
[f. polarization + -o + -graph.]
An apparatus for automatic chemical analysis in which a sample solution is electrolysed using a steadily increasing voltage, and a graph, known as a polarogram, of current against voltage is produced; this usu. shows a series of steps each of which occurs at a voltage characteristic of a particular component and has a height proportional to the concentration of that component.
Polarograph is a proprietary term in the U.S.A.
1925Heyrovský & Shikata in Recueil Travaux Chimiques Pays-Bas XLIV. 496 (heading) The polarograph. 1933Official Gaz. (U.S. Patent Office) 15 Aug. 527/1 Polarograph Laboratories of America, Berkeley, Calif. Filed June 5, 1933. Polarograph. For Electrical Analyzing Apparatus... Claims use since Feb. 1, 1927. 1937Jrnl. Iron & Steel Inst. CXXXVI. 109a From the current-potential curve the deposition potential for a given level on the curve can be determined, so that the polarograph can be used as a qualitative test. 1946Nature 13 July 59/1 Iron can be determined satisfactorily on the polarograph if the solution contains triethanolamine. 1953Electronic Engin. XXV. 314/1 One such instrument is the polarograph, which is used to determine the concentration of reducible ions in a solution, by measurement of the current that flows when the ions are electrolytically reduced. 1974S. E. Allen Chem. Analysis Ecol. Materials 400 Oxygen is the only dissolved gas of interest to biologists which can be readily determined on the polarograph.
Hence polaroˈgraphic a., of, pertaining to, or used in a polarograph or polarography; polaroˈgraphically adv.; polaˈrography, the technique of using the polarograph.
1926Brit. Chem. Abstr. A. 1184/1 (heading) Polarographic methods in biology. 1930Chem. News 19 Dec. 388/2 Current-voltage curves obtained polarographically..reveal the presence of proteins in solutions. 1936Nature 30 May 889/2 The last section, on polarography by Prof. J. Heyrovský, gives a comprehensive survey of the researches with the dropping mercury cathode. 1952Kolthoff & Lingane Polarography (ed. 2) xviii. 397 This reaction may be utilized to remove dissolved oxygen from polarographic solutions. 1959Times 30 Jan. 3/7 This involves supervision of staff engaged on a variety of analytical work, including..infra-red spectroscopy and polarography. 1966McGraw-Hill Encycl. Sci. & Technol. X. 455/1 The most widely used polarographic indicator electrode is the dropping-mercury electrode. 1970C. N. Graymore Biochem. Eye x. 651 Noell..measured oxygen tension polarographically. 1973Nature 10 Aug. 370/2 Characteristic polarographic half-wave potential..values for proteins were attributed..to exposed, reactive sulphydryl..groups. 1975M. R. Jenkins in Williams & Wilson Biologist's Guide to Princ. & Techniques Pract. Biochem. vii. 200 The main use of polarography in biochemistry is not, however, the measurement of oxidation-reduction potentials, but rather the qualitative and quantitative analysis of various compounds. |