| 释义 |
nitrogen Chem.|ˈnaɪtrədʒən|
Also 8–9 -gene.
[ad. F. nitrogène (Chaptal 1790): see nitro- and -gen 1.]
a. A ‘permanent’ gas (symbol N), without colour, taste, or smell, which forms about four-fifths of the atmosphere.
1794Pearson in Phil. Trans. LXXXIV. 391 The remainder of the gaz extinguished flame, and was concluded to be nitrogen or azotic gaz. 1806Davy in Phil. Trans. XCVII. 11 Hydrogene, during its solution in water, seems to expel nitrogene. 1825Faraday Exp. Res. xxvii. 151, I have refrained from all reasoning on the probability of the compound nature of nitrogen. 1856Orr's Circ. Sci., Pract. Chem. 306 Nitrogen, carbon, and hydrogen are to be found in all living bodies. 1870Emerson Soc. & Sol., Clubs, The flame of life burns too fast in pure oxygen, and nature has tempered the air with nitrogen.
b. attrib. and Comb. nitrogen-containing adj.; nitrogen cycle Biol., the cycle of changes whereby nitrogen is interconverted between its free state in the air and combined states in organisms and the soil; nitrogen fixation, the conversion of free, gaseous nitrogen into a combined form; cf. fixation 2 d; so nitrogen fixer, a nitrogen-fixing organism; nitrogen-fixing ppl. a., bringing about nitrogen fixation; nitrogen mustard, any of the group of substances containing the group {b1}N(CH2CH2Cl)2, which are cytotoxic as a result of their alkylating property and some of which are used in treating neoplastic diseases, such as Hodgkin's disease and lymphosarcoma; nitrogen narcosis, a narcotic state, common among divers, induced by breathing air under pressure.
1894Field 9 June 844/2 The *nitrogen-collecting power of leguminous crops.
1862Spencer First Princ. ii. xiii. §101 (1875) 295 These *nitrogen-compounds are unusually prone to decomposition.
1956Nature 4 Feb. 234/1 A *nitrogen-containing acid. 1967Oceanogr. & Marine Biol. V. 168 If some of the nitrogen-containing gases (evolved during the digestion procedure) escape..the values obtained may be too low.
1908Hall & Defren tr. Abderhalden's Text-bk. Physiol. Chem. x. 198 The discovery that ordinary nitrogen can be directly assimilated closes the chain of the *nitrogen cycle, which had apparently been broken open by the discovery of the denitrifying organisms. 1931E. Ashby tr. Lundegårdh's Environment & Plant Devel. viii. 242 The nitrogen cycle..lies to a great degree, though not exclusively, in the soil. 1966McGraw-Hill Encycl. Sci. & Technol. IX. 111/2 The nitrogen cycle comprises the processes of ammonification, nitrification, denitrification, and nitrogen fixation.
1895Lawes & Gilbert Rothamsted Exper. 164 Recently acquired knowledge in regard to *nitrogen fixation. 1938Nature 12 Nov. 878/1 Diverse workers..have previously affirmed nitrogen fixation by Blue-green Algæ. 1970Sunday Times (Colour Suppl.) 16 Aug. 13/1 It is likely that Germany would have collapsed before 1918 but for the nitrogen fixation plants built in 1914–16.
1912E. J. Russell Soil Conditions & Plant Growth iv. 83 In all these cases leguminous plants are present in greatest extent where the gains in nitrogen are greatest, but they are not necessarily the only *nitrogen fixers. 1932Fuller & Conard tr. Braun-Blanquet's Plant Sociol. viii. 235 Anaerobic and aerobic nitrogen fixers often occur associated together in the same soil. 1968Jrnl. Gen. Microbiol. L. 487 As these small colonies grew abundantly on nitrogen-poor agar, it was thought possible that some of them might be nitrogen-fixers.
1899F. H. King Irrigation & Drainage 233 The *nitrogen-fixing tubercles were already developed. 1929Weaver & Clements Plant Ecol. x. 249 Both nitrifying and nitrogen-fixing bacteria thrive in the humus. 1966New Statesman 2 Dec. 826/1 The first new component isolated from the Du Pont nitrogen-fixing system. 1970Nature 25 July 378/1 The nitrogen-fixing enzyme complex, nitrogenase, catalyses various reductions as well as the formation of ammonia from dinitrogen.
1815J. Smith Panorama Sci. & Art II. 348 *Nitrogen gas is most easily described by including many of its negative qualities.
1946Jrnl. Amer. Med. Assoc. 21 Sept. 132/1 Although indications and contraindications for the use of the *nitrogen mustards remain to be established definitively, it is felt that these agents are deserving of further clinical trial. 1951New Biol. XI. 97 In the treatment of leukaemia..several different classes of chemicals show some value. There are some compounds, such as the nitrogen mustards, which imitate the action of radiation on the cell, and dislocate nuclear division. 1970Passmore & Robson Compan. Med. Stud. II. xxix. 5/1 Chlorambucil..can be given by mouth and is the slowest acting and least toxic of all the nitrogen mustards in clinical use.
1937U.S. Naval Med. Bull. XXXV. 379 It is well known that if pressure is applied too quickly the diver becomes dizzy and often is so dazed as to require several minutes to orient himself. Consequently, if the cause were *nitrogen narcosis, the difficulty would increase with exposure rather than decrease. 1962Listener 29 Mar. 562/1 Free deep-sea divers—that is to say, divers wearing cylinders filled with compressed air—may suffer at varying depths from a mild intoxicating effect, or ‘rapture of the deep’, known as nitrogen narcosis. 1972Aerospace Med. XLIII. 1079 (heading) Diver performance: nitrogen narcosis and anxiety.
1869Roscoe Elem. Chem. 63 Nitric acid may be considered as a compound of *nitrogen pentoxide with water.
Hence nitroˈgeneous a., nitroˈgenic a., = nitrogenous. nitrogeˈniferous a., producing nitrogen. niˈtrogenize v. trans., to combine with nitrogen; spec. = nitride v.; also nitrogeniˈzation, the action or result of nitrogenizing.
1836Smart, *Nitrogeneous. 1894Field 9 June 844/2 The natural stores of nitrogeneous substances in the soil.
1889Nature 25 July 312/1 The action of nitric acid on carbonic and *nitrogenic compounds.
1836–41Brande Man. Chem. (ed. 5) 1256 An azotized or *nitrogeniferous substance.
1896Jrnl. Iron & Steel Inst. L. 161 Iron specially *nitrogenised by the action of ammonia is materially altered in character. 1897Cheyne & Burghard Man. Surg. Treat. i. v. 97 The plan of inducing anæsthesia with nitrous oxide, and maintaining the narcosis with ether (nitrogenizing the ether). 1916Engineering 3 Mar. 218/2 A sample of iron was taken, nitrogenised at 600 deg.,..and then thrown out from the Heraeus furnace into very cold water.
1903Lancet 6 June 1590/1 The increased *nitrogenisation of the soil by the widened use of phosphatic manures. 1922Engineering 29 Sept. 413/1 To obtain positive evidence of nitrogenisation both unannealed and annealed specimens of armco iron were analysed for nitrogen. 1926Chem. Abstr. XX. 2138 In Ni and Mn steels nitrogenization produced hardly any increase in hardness. |