| 释义 |
Tyndall|ˈtɪndəl|
The name of John Tyndall, an English physicist (1820–1893), used attrib. with reference to the scattering of a beam of light by small particles and the blue colour that the scattered light often has (described by Tyndall in 1869).
1910H. H. Hodgson tr. Pöschl's Introd. Chem. of Colloids ii. 12 The Tyndall effect is the basis of ultra⁓microscopy. 1915M. H. Fischer et al. tr. Ostwald's Handbk. Colloid-Chem. 8 Liquids which show no definite Tyndall light-cone..are molecular-disperse solutions. 1925G. Barger tr. Freundlich's Elem. Colloidal Chem. 125 All colloidal solutions with colourless particles show a blue Tyndall light. 1939H. B. Weiser Colloid Chem. xii. 160 There is no pigment in blue eyes; the color is a Tyndall blue which is more intense the finer the particles that give rise to the blue color. 1964Oceanogr. & Marine Biol. II. 366 With the searchlights [of the bathyscaph] on, it is possible to discern very minute particles..by the Tyndall effect. 1966McGraw-Hill Encycl. Sci. & Technol. XIV. 169/1 In aqueous gold sols..strong Tyndall cones are observed. 1971Nature 19 Feb. 573/1 Drops smaller than 1 µm form a ‘blue haze’ due to selective Tyndall scattering of shorter light wavelengths.
Hence ˈTyndallmeter (also as two words), Tyndaˈllometer, an instrument that makes use of the Tyndall effect for measuring aerosols and suspensions.
1919Tolman & Vliet in Jrnl. Amer. Chem. Soc. XLI. 297 (heading) A Tyndallmeter for the examination of disperse systems. 1937Nature 25 Sept. 553/1 The hygienic importance of the reduction of dust lends interest to means for its measurement, and the Tyndallometer shown by E. Leitz (London) provides a new and rapid means of its measurement. 1957H. C. van de Hulst Light Scattering by Small Particles xix. 405 This problem, of obvious importance in the testing of gas masks, was studied by Gucker and by O'Konski. A Tyndall meter is insufficient for the concentrations of 10-9g/liter and lower that have to be investigated. |