| 释义 |
photochemical, a.|fəʊtəʊˈkɛmɪkəl|
[f. photo- + chemical.]
Of or pertaining to the chemical action of light; photochemical smog, a condition of the atmosphere attributed to the action of sunlight on hydrocarbons and nitrogen in it and characterized by the presence of aerosols and increased ozone and nitrogen oxides and by effects that include irritation of the eyes, damage to plants, and visibility reduced to a mile or less.
1859Sat. Rev. 26 Feb. 242/1 The use of that bichromate of potassium to which we alluded before as the foundation of so many of these ingenious combinations of photochemical changes and mechanical inventions. 1888Meldola Chem. Photogr. i. (1889) 7 By a photo-chemical action must be understood a chemical change produced by the action of light. 1957Rep. Air Pollution Foundation (U.S.) No. 21. 1 It is now realized that Los Angeles' smog is primarily a reaction between organic matter and nitrogen oxides in the presence of sunlight. The need for irradiation to produce the reaction has led to the designation ‘photochemical’ smog. 1972Daily Colonist (Victoria, B.C.) 13 Feb. 27/5 His studies of animals show that Vitamin E serves as an antioxidant to protect lung tissue from damage by the ozone in photochemical smog. 1972Nature 18 Feb. 360/1 There is no doubt that motor vehicles are the principal outlets for photochemical smog in large cities. 1976New Yorker 16 Feb. 74/2 Los Angeles is perhaps the best-known victim of the bus and the automobile; photochemical smog, the distinctive pollutant of these vehicles, made its first recorded appearance in Los Angeles in 1943.
Hence photoˈchemically adv.; photoˈchemist, one versed in photochemistry; photoˈchemistry, that part of chemistry which deals with the chemical action of light.
1867M. Carey Lea in Amer. Jrnl. Sci. Ser. 2. XLIV. 71 The nature of the action of light upon iodid of silver,..the most important..of all the facts of photochemistry. 1881Phil. Mag. XII. 21 The impression of an electromotive force upon a film possessing, as do all photochemically active bodies, electrolytic conductivity, will tend to produce at least partial electrolysis. 1898Daily News 15 Apr. 5/6 It works photo-chemically. 1926Trans. Faraday Soc. XXI. 438 Stark's views undoubtedly did not receive from photochemists the attention they deserved. 1941S. H. Bartley Vision i. 5 The photochemist has given increasing attention to the cycle of changes that occur in the eye in response to light. 1961G. R. Choppin Exper. Nucl. Chem. xii. 194 It is tempting to seek to relate photochemistry and radiation chemistry by considering that ionization is the ultimate state of excitation. 1967Margerison & East Introd. Polymer Chem. iv. 184 The process is started by the decomposition of an initiator induced thermally, photochemically or by admixture of another substance. 1972DePuy & Chapman Molec. Reactions & Photochem. i. 6 Photochemistry is the study of the chemistry of electronically excited molecules produced by the absorption of electromagnetic radiation. 1973Sci. Amer. Apr. 68/2 Photochemists have measured the probability that ultraviolet photons will destroy particular molecules. 1978Nature 23 Feb. 733/1 Photochemically produced sulphate aerosols can, in certain circumstances, account for a large proportion of total particulate mass in the 0·1–1·0 µm size range. |