释义 |
Hittorf|ˈhɪtɔːf| The name of Johann Wilhelm Hittorf (1824–1914), German scientist, used attrib. and occas. in the possessive to denote various phenomena, pieces of apparatus, techniques, and concepts observed or invented by him, as Hittorf dark space = Crookes dark space; Hittorf method, a method of finding the transport numbers of ions in an electrolyte by measuring the change in concentration of the ions near the electrodes during electrolysis; Hittorf transport (or transference) number, a transport number as found by the Hittorf method.
1893T. O'C. Sloane Stand. Electr. Dict. 289 Hittorf's solution, a solution sometimes used as a resistance. It is a solution of cadmium iodide in amylic alcohol. Ibid. 466 Hittorf's resistance, a high resistance, often a megohm, composed of Hittorf's solution. 1897M. M. P. Muir tr. Lüpke's Elem. Electro-Chem. i. iii. 41 (heading) Hittorf's transport-numbers. 1909Jrnl. Amer. Chem. Soc. XXXI. 351 (heading) The relation between the true transference number and the Hittorf transference number. Ibid., The ordinary transference number (TH) for concentrated solutions, as obtained by the Hittorf method, is erroneous in cases where the ions are hydrated, since it is calculated on the assumption that the water remains stationary during the passage of the current. 1916F. B. Pidduck Treat. Electr. xii. 487 The negative glow and the Hittorf dark space expand continually as the pressure is reduced. 1941J. D. Cobine Gaseous Conductors viii. 213 Following the cathode glow is another dark space variously called the cathode dark space, the Crookes dark space, the Hittorf dark space. 1942Glasstone Introd. Electrochem. vi. 114 Although the Hittorf method is simple in principle, accurate results are difficult to obtain. |