| 释义 |
Nessler Chem.|ˈnɛslə(r)|
The name of Julius Nessler (1827–1905), German agricultural chemist, used attrib. and in the possessive with reference to a delicate test for ammonia he devised; as Nessler('s) reagent or solution, an alkaline solution of potassium mercuric iodide, which gives a yellow or brown colour or precipitate when added to an aqueous solution containing ammonia; Nessler('s) tube, a glass cylinder marked with a line indicating a certain volume and depth, used in nesslerization and other colorimetric procedures.
1865Jrnl. Chem. Soc. XVIII. 125 The distillate is divided into two equal portions; one of these is submitted to Nessler's test for ammonia. 1868Ibid. XXI. 87 Mr. Chapman..recommends that the ammonia determination should be made by the application of Nessler's solution directly to the water. Ibid., Waters containing chalk in solution become turbid on the addition of the Nessler test. 1873Chem. News 11 July 13/2 The time required for the development of the Nessler colour. Ibid., One sample of Nessler reagent gives its maximum of colour almost immediately, and another takes a quarter of an hour or an hour. 1913Cumming & Kay Text-bk. Quantit. Chem. Anal. iv. 156 Measure into a 100 c.c. Nessler tube a portion of the solution containing from 0·1 to 3 mgrm. of iron. 1946Thorpe's Dict. Appl. Chem. (ed. 4) VII. 579/1 The action of ammonia on an alkaline solution of potassium mercuri-iodide..is the basis of the Nessler test for ammonia. 1963Skoog & West Fund. Analytical Chem. xxviii. 656 In its simplest form, colorimetry consists of visual matching of the color of the solutions of the substance with a set of standards. For such a procedure flat-bottomed tubes called Nessler tubes are frequently employed. 1970Nessler's reagent [see nesslerization]. |