nitrogenn.

Brit.

/ˈnʌɪtrədʒ(ə)n/, U.S.

/ˈnaɪtrədʒ(ə)n/

Forms: 1700s–1800s nitrogene, 1700s– nitrogen.

Origin: A borrowing from French. Etymon: French nitrogène.

Etymology: < French nitrogène (1790 in the passage translated in quot. 1791 at sense 1) < nitro- nitro- comb. form + -gène -gen comb. form.

1. A non-metallic chemical element, atomic no. 7, which, as a colourless, odourless gas with diatomic molecules (N₂), forms approximately four-fifths of the earth's atmosphere, and which is also a constituent of numerous compounds, including ammonia, nitric acid, nitrates, and proteins. Also as a count noun: an atom of this element. Symbol N. Recorded earliest in nitrogen gas n. at Compounds 1a.

ΘΚΠ

the world > matter > chemistry > elements and compounds > metals > specific elements > nitrogen > [noun]

alkaligen1788

azote1791

nitrogen1791

septon1795

N1814

1789 R. Kerr tr. A. Lavoisier Elements Chem. i. iv. 53 It [sc. azotic gas] is proved to compose a part of the nitric acid, which gives as good reason to have called it nitrigen.]

1791 W. Nicholson tr. J. A. C. Chaptal Elements Chem. I. p. xxxv The denomination of Azotic Gas is not established according to the principles which have been adopted... In order to correct the nomenclature..I have presumed to propose that of Nitrogene Gas... It is deduced from the characteristic and exclusive property of this gas, which forms the radical of the nitric acid.

1794 Philos. Trans. (Royal Soc.) 84 391 The remainder of the gaz extinguished flame, and was concluded to be nitrogen or azotic gaz.

1807 H. Davy in Philos. Trans. (Royal Soc.) 97 11 Hydrogene, during its solution in water, seems to expel nitrogene.

1825 M. Faraday Exper. Res. xxvii. 151 I have refrained from all reasoning on the probability of the compound nature of nitrogen.

1856 Orr's Circle Sci.: Pract. Chem. 306 Nitrogen, carbon, and hydrogen are to be found in all living bodies.

1910 Science 16 Sept. 367/2 The oxidation of ammonia and other organic compounds of nitrogen to the state of nitrate was one of the first actions in the soil which was proved to be brought about by bacteria.

1953 Life 8 June 80/2 Known as ‘airglow’, this faint luminescence is emitted by sodium, oxygen and nitrogen molecules and atoms excited by sunlight during the day.

1990 Sunday Express Mag. 15 Apr. 31/3 If there is not enough leafy material around, extra nitrogen can be added in the form of manure, seaweed meal or dried blood.

2006 J. M. Hornback Org. Chem. (Internat. Student ed.) x. 366 Iodomethane and similar reagents can act as carcinogens by alkylating the nitrogens in the bases of DNA.

2. A nitrogen compound, esp. one used as a fertilizer.

ΚΠ

1870 Chem. News 14 Oct. 184/1 The nitrogens are..pretty near the theoretical quantities.

1932 Amer. Jrnl. Surg. 15 477/2 Out of 36 cases of alkalosis, 9 had elevated non-protein nitrogens in the blood.

1957 M. Lamer World Fertilizer Econ. ix. 140 Agricultural demand for nitrogenous fertilizers was high enough, and the preference for some of the other nitrogens strong enough.

2013 Press & Jrnl. (Aberdeen) (Nexis) 13 May 8 You need to understand the growing aspects of the [grain] crop so you get the nitrogens, grain size and other specifications required.

Compounds

C1.

nitrogen compound n.

ΚΠ

1846 Littell's Living Age 17 Oct. 120/2 A cotton is prepared, by a process not yet divulged—but which is in all probability one that depends on the formation of a nitrogen compound.

1932 G. D. Fuller & H. S. Conard tr. J. Braun-Blanquet Plant Sociol. viii. 236 The nitrogen compounds in the soil must generally be converted into nitric acid.

1991 Independent 1 Nov. 17/3 Whether the released, inorganic, nitrogen compounds run off and pollute, or are taken up by crops, depends partly on rainfall.

nitrogen gas n.

ΚΠ

1791Nitrogene gas [see sense 1].

1803 F. Accum Syst. Theoret. & Pract. Chem. I. 139 One of the most remarkable combinations into which nitrogen is known to enter, is that which takes place between it and light and caloric. The compound thus produced is called nitrogen gas.

1945 Science 12 Jan. 42/2 The International Standard..after complete desiccation shall be sealed in three containers in pure dry nitrogen gas.

1991 Acta Metallurgica et Materialia 39 2519/2 The solutions were continuously deaerated during experiments by bubbling of purified nitrogen gas.

nitrogen-collecting adj.

ΚΠ

1894 Field 9 June 844/2 The nitrogen-collecting power of leguminous crops.

1901 Bull. Torrey Bot. Club 28 528 It appears that we must add palms to the Leguminosae, Podocarpus, Alnus, and Cycas as plants which have, as it were, domesticated nitrogen-collecting soil organisms.

nitrogen-containing adj.

ΚΠ

1855 J. P. Norton Elements Sci. Agric. 140 When these substances are subjected to chemical analysis, they are proved to belong to the same class, and to have a composition agreeing, with that of the nitrogenous or nitrogen-containing bodies of the plant.

1898 B. P. Colton Physiol. vi. 161 Urea is the nitrogen-containing waste.

1994 Sci. Amer. Mar. 64/3 Protein and other nitrogen-containing compounds.

C2.

nitrogen balance n. the relationship between the amounts of nitrogen entering and leaving a biological system; spec.: (a) Physiology the difference between the amounts of nitrogen taken in and excreted by an organism; (b) Soil Science the difference between the amount of nitrogen added to a soil (by fertilization, nitrogen fixation, etc.) and the amount removed (by cropping, leaching, denitrification, etc.).

ΚΠ

1897 Science 24 Dec. 949/1 The administration of thyroid tablets was stopped, and..the nitrogen balance became positive immediately and the body weight increased rapidly.

1942 Science 31 July 97/1 Karraker has published reports on these and other phases of the nitrogen balance in soils since 1925.

1988 P. W. Kuchel et al. Schaum's Outl. Theory & Probl. Biochem. xv. 411 The amount of protein (or fixed nitrogen) we ingest determines the state of nitrogen balance.

1993 Appl. & Environmental Microbiol. 59 3026/1 Nitrogen fixation by free-living N₂ fixers..makes a significant contribution to the nitrogen balance of desert grassland communities.

nitrogen cycle n. Biology the cycle of changes whereby nitrogen is interconverted between its free state in the air and combined states in organisms and the soil.

ΘΚΠ

the world > life > biology > balance of nature > environment or habitat > [noun] > sulphur or nitrogen cycle

nitrogen cycle1906

sulphur cycle1967

1906 Science 12 Jan. 576/1 River waters differ from pond, lake of reservoir, waters in the essential particular that the former are in rapid motion and the so-called nitrogen cycle may take place several times during the course of their flow.

1966 McGraw-Hill Encycl. Sci. & Technol. (rev. ed.) IX. 111/2 The nitrogen cycle comprises the processes of ammonification, nitrification, denitrification, and nitrogen fixation.

1984 N. N. Greenwood & A. Earnshaw Chem. of Elements (1986) xi. 469 The continuous interchange of nitrogen between the atmosphere and the biosphere is called the nitrogen cycle.

nitrogen dioxide n. †(a) nitric oxide, NO, erroneously assigned the formula N₂O₂ (obsolete); (b) a poisonous and reactive brown gas, NO₂, which below 140°C exists in a temperature-dependent equilibrium with nitrogen tetroxide (increasing amounts of the latter being formed on cooling), and which is used in nitric acid production and as a nitrating and oxidizing agent.

ΚΠ

1844 G. Fownes Man. Elem. Chem. 114 Deutoxide, or binoxide of nitrogen.]

1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vi. 58 (table) Nitrogen Di-oxide containing 28 parts by weight of N. to 32—O.

1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vi. 72 Nitrogen Dioxide, or Nitric Oxide.

1925 Ann. Missouri Bot. Garden 12 368 In several cases there was a visible evolution of nitrogen dioxide fumes.

1950 Effects of Atomic Weapons (Los Alamos Sci. Lab.) ii. 30 The brownish or peachlike tint of the cloud which has been reported..is apparently due to nitrogen dioxide.

1990 D. F. Shriver et al. Inorg. Chem. xii. 380 Nitrogen( iv) oxide, commonly nitrogen dioxide, exists as an equilibrium mixture of the brown NO₂ radical and its colorless dimer N₂O₄.

nitrogen fixation n. the conversion, esp. by bacteria, of gaseous nitrogen into a combined form that is usable by plants.

ΘΚΠ

the world > life > biology > biological processes > metabolism > [noun] > metabolic processes

metastasis1861

respiration1882

nitrogen fixation1893

turn-over1943

the world > matter > chemistry > chemical reactions or processes > [noun] > chemical reactions or processes (named) > fixation > of nitrogen

fixation1850

nitrogen fixation1893

1893 Amer. Naturalist 27 1053 The germ theories of fermentation, of nitrification, of sewage filtration, of nitrogen fixation, of the etiology of contagious diseases..are monumental witnesses of the value of this department in the realm of pure science.

1938 Nature 12 Nov. 878/1 Diverse workers..have previously affirmed nitrogen fixation by Blue-green Algæ.

1970 Sunday Times 16 Aug. (Colour Suppl.) 13/1 It is likely that Germany would have collapsed before 1918 but for the nitrogen fixation plants built in 1914–16.

nitrogen fixer n. an organism which brings about nitrogen fixation.

ΘΚΠ

the world > life > biology > balance of nature > organisms in relation to habitat > [noun]

colonist1839

benthos1891

land form1897

heterotroph1900

autotroph1901

epibenthos1902

specialist1902

microaerophile1903

nitrifier1903

consumer1904

nitrogen fixer1904

producer1904

indicator1906

psychrophile1906

thermophil1909

sulphuretum1925

influent1926

halobiont1928

halophile1928

mesophile1928

oligosaprobe1931

saprobe1932

eurytope1938

stenotope1938

photoautotroph1939

chemoautotroph1943

prototroph1946

mixotrophy1948

chemolithoautotroph1949

auxotroph1950

chemoheterotroph1951

chemoorganotroph1953

chemolithotroph1955

chemotroph1958

osmophile1961

psychrotroph1963

saprotroph1963

generalist1964

opportunist1967

cryophile1970

1904 Science 30 Sept. 433/1 The legume bacteria are nitrogen fixers without any aid from leguminous plants.

1932 G. D. Fuller & H. S. Conard tr. J. Braun-Blanquet Plant Sociol. viii. 235 Anaerobic and aerobic nitrogen fixers often occur associated together in the same soil.

1997 Internat. Jrnl. Plant Sci. 158 828/1 Spartium junceum is a nitrogen-fixer, and both leaf and stem photosynthesis are inhibited if tissue nitrogen levels drop appreciably.

nitrogen-fixing adj. of, relating to, or bringing about nitrogen fixation.

ΘΚΠ

the world > life > biology > biological processes > metabolism > [adjective] > processes

metastatic1880

nitrogen-fixing1890

1890 Proc. Royal Soc. 1889–90 47 113 The development of the supposed nitrogen-fixing organisms obviously depends on the infection of the soil with the organism essential to symbiotic life with the particular leguminous crop to be grown.

1929 J. E. Weaver & F. E. Clements Plant Ecol. x. 249 Both nitrifying and nitrogen-fixing bacteria thrive in the humus.

1966 New Statesman 2 Dec. 826/1 The first new component isolated from the Du Pont nitrogen-fixing system.

1991 Garbage Jan. 45/2 Bailey's acacia (Acacia baileyana), a nitrogen-fixing leguminous type from Australia, is one of the most drought-tolerant trees available.

nitrogen monoxide n. (a) = nitrous oxide n. at nitrous adj. and n. Compounds (rare); (b) = nitric oxide n. at nitric adj. Compounds.

ΘΚΠ

the world > matter > chemistry > chemical substances > named gases > [noun] > containing nitrogen

nitrous gas1742

nitrous air1772

nitric oxide1789

nitrogen monoxide1869

nitrox1982

the world > matter > chemistry > chemical substances > named gases > [noun] > containing nitrogen > nitrous oxide

nitrous oxide1799

laughing gas1819

nitrogen monoxide1869

nitrous1977

1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vii. 69 The salt decomposes on heating into nitrogen monoxide and water.

1922 T. M. Lowry Inorg. Chem. xxvi. 401 (note) Nitric oxide (or nitrogen monoxide)... This [latter] name is sometimes applied loosely to dinitrogen monoxide, N₂O, and is therefore too ambiguous to be used safely.

1992 Science 18 Dec. 1898/1 Nitrogen monoxide (NO) has been implicated in a number of diverse physiological processes.

nitrogen mustard n. any of a class of compounds containing the group —N(CH₂CH₂Cl)₂ (a side chain similar to the mustard gas molecule), which have alkylating properties and are cytotoxic, some being used to treat cancers.

ΘΚΠ

the world > health and disease > healing > medicines or physic > medicines for specific purpose > preparations treating or preventing specific ailments > [noun] > for tumour

platinum blue1908

nitrogen mustard1943

mustard1945

piperoxan1950

melphalan1960

procarbazine1965

bleomycin1966

1943 Science 24 Dec. 10/2 New war gases, nitrogen mustards, were developed and found to have a milder blistering action than mustard gas and to cause blindness.

1970 R. Passmore & J. S. 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.

1991 New Scientist 31 Aug. 20/1 They use so-called nitrogen mustard as the cell-killing, or cytotoxic, component.

nitrogen narcosis n. a narcotic state which is induced by breathing air under pressure and occurs esp. in divers.

ΘΚΠ

the world > health and disease > ill health > a disease > disorders of internal organs > stupor or coma > [noun] > specific coma

coma vigil1708

hydrocephaloid disease1842

nitrogen narcosis1937

insulin coma1942

rapture of the deep1953

narks1962

1937 U.S. Naval Med. Bull. 35 379 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.

1962 Listener 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.

1990 Alert Diver May 3 Much is still unknown about decompression sickness, oxygen toxicity, and nitrogen narcosis.

nitrogen oxide n. each of the seven oxides of nitrogen; spec. any one or a mixture of these oxides released into the environment as a result of fuel combustion (esp. nitric oxide, NO, and nitrogen dioxide, NO₂).

ΚΠ

1868 H. B. Jones & H. Watts Fownes's Man. Elem. Chem. (ed. 10) 158 The other three nitrogen oxides do not form salts.

1957 Rep. Air Pollution Foundation (U.S.) No. 21. 1 It is now realised that Los Angeles' smog is primarily a reaction between organic matter and nitrogen oxides in the presence of sunlight.

1990 Sci. Amer. May 59/1 The Clean Air Act of 1970, soon to be amended, limits the hydrocarbon, carbon monoxide and nitrogen oxide emissions that are permitted in tail-pipe exhaust.

nitrogen pentoxide n. a colourless solid, N₂O₅ (or NO₂⁺.NO₃⁻), which is a strong oxidizing agent that reacts with water to form nitric acid (also called dinitrogen pentoxide).

ΚΠ

1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vi. 63 Nitric acid may be considered as a compound of nitrogen pentoxide with water.

1922 Science 17 Nov. 577/1 The decomposition of nitrogen pentoxide..is a unimolecular, gas phase reaction which takes place at room temperature.

1993 New Phytologist 124 268/1 Ozone generated by electric discharge from the air may be contaminated by nitrogen compounds, e.g. nitrogen pentoxide.

nitrogen peroxide n. nitrogen dioxide and nitrogen tetroxide, considered as a single substance in two forms.

ΚΠ

1842 T. Graham Elements Chem. 282 Peroxide of Nitrogen (nitrous acid of Turner, hyponitric acid of Thenard)..NO₄.]

1874 Index Jrnl. Chem. Soc. 198/1 Nitrogen peroxide. See Nitrogen Tetroxide.

1955 B. C. L. Kemp Elem. Org. Chem. (new ed.) x. 152 The oxidizing action of concentrated nitric acid is catalysed by the presence of nitrogen peroxide (NO₂).

1996 Milling & Baking News (Nexis) 3 Dec. 34 The earliest attempts were made in the United Kingdom, using ozone as the bleaching agent. Nitrogen peroxide was next used.

nitrogen tetroxide n. a colourless volatile liquid, N₂O₄, which exists in temperature-dependent equilibrium with nitrogen dioxide, and is used as a nitrating agent, a solvent, and an oxidizer in rocket fuels (also called dinitrogen tetroxide).

ΚΠ

1866 H. E. Roscoe Lessons Elem. Chem. vi. 53 Nitrogen tetroxide containing 28 parts by weight of N. to 64 of O.

1969 Times 3 June (Suppl.) p. iii/7 All three systems were propelled by nitrogen tetroxide.

1994 N.Y. Times 11 Jan. c11/1 An investigating panel..said that a small amount of liquid nitrogen tetroxide, about two tablespoons, probably leaked during the long cold journey and condensed upstream.

nitrogen trichloride n. a pungent, explosive yellow oil, NCl₃, made by reaction of ammonia with excess chlorine and formerly used to bleach and age flour.

ΚΠ

1889 I. Remsen Inorg. Chem. xvii. 292 According to this, the trichloride of nitrogen is the final product of the substituting action of chlorine upon ammonia.]

1896 Science 3 July 28/2 They show an analogy to nitrogen trichloride in their instability.

1947 Lancet 23 Aug. 284/1 Acceptibility of bread as an article of food is largely increased by the use of an ‘improver’... The one in most extensive use in this country..is nitrogen trichloride: known commercially as ‘agene’.

1988 F. A. Cotton & G. Wilkinson Adv. Inorg. Chem. (ed. 5) x. 331 Nitrogen trichloride..is formed in the chlorination of the slightly acid solutions of NH₄Cl.

nitrogen trioxide n. (a) the anhydride of nitrous acid, N₂O₃, which is a blue liquid (made greenish by dissolved nitrogen dioxide) which decomposes above 3.5°C (also called dinitrogen trioxide); (b) an unstable gaseous oxide of nitrogen, NO₃, identified chiefly by its absorption spectrum.

ΚΠ

1868 H. B. Jones & H. Watts Fownes's Man. Elem. Chem. (ed. 10) 161 Nitrogen trioxide, or nitrous oxide... A mobile blue liquid, which emits orange-red vapors.

1936 Jrnl. Chem. Soc. 1412 When ozonized oxygen is passed over nitric anhydride, a gas with a blue tint is produced, which probably contains nitrogen trioxide, NO₃.

1938 R. Hum Chem. for Engin. Students xv. 362 Nitrogen trioxide [N₂O₃]..is obtained as a blue liquid when a mixture of nitric oxide and nitrogen peroxide is passed through a U-tube immersed in a freezing mixture at −30°C.

1966 Proc. Royal Soc. A. 295 82 It appears that under these conditions, nitrogen trioxide, if formed, reacts almost entirely with nitric oxide rather than with sulphur dioxide.

This entry has been updated (OED Third Edition, December 2003; most recently modified version published online March 2022).

单词	nitrogen
释义	nitrogenn. Brit. /ˈnʌɪtrədʒ(ə)n/, U.S. /ˈnaɪtrədʒ(ə)n/ Forms: 1700s–1800s nitrogene, 1700s– nitrogen. Origin: A borrowing from French. Etymon: French nitrogène. Etymology: < French nitrogène (1790 in the passage translated in quot. 1791 at sense 1) < nitro- nitro- comb. form + -gène -gen comb. form. 1. A non-metallic chemical element, atomic no. 7, which, as a colourless, odourless gas with diatomic molecules (N₂), forms approximately four-fifths of the earth's atmosphere, and which is also a constituent of numerous compounds, including ammonia, nitric acid, nitrates, and proteins. Also as a count noun: an atom of this element. Symbol N. Recorded earliest in nitrogen gas n. at Compounds 1a. ΘΚΠ the world > matter > chemistry > elements and compounds > metals > specific elements > nitrogen > [noun] alkaligen1788 azote1791 nitrogen1791 septon1795 N1814 1789 R. Kerr tr. A. Lavoisier Elements Chem. i. iv. 53 It [sc. azotic gas] is proved to compose a part of the nitric acid, which gives as good reason to have called it nitrigen.] 1791 W. Nicholson tr. J. A. C. Chaptal Elements Chem. I. p. xxxv The denomination of Azotic Gas is not established according to the principles which have been adopted... In order to correct the nomenclature..I have presumed to propose that of Nitrogene Gas... It is deduced from the characteristic and exclusive property of this gas, which forms the radical of the nitric acid. 1794 Philos. Trans. (Royal Soc.) 84 391 The remainder of the gaz extinguished flame, and was concluded to be nitrogen or azotic gaz. 1807 H. Davy in Philos. Trans. (Royal Soc.) 97 11 Hydrogene, during its solution in water, seems to expel nitrogene. 1825 M. Faraday Exper. Res. xxvii. 151 I have refrained from all reasoning on the probability of the compound nature of nitrogen. 1856 Orr's Circle Sci.: Pract. Chem. 306 Nitrogen, carbon, and hydrogen are to be found in all living bodies. 1910 Science 16 Sept. 367/2 The oxidation of ammonia and other organic compounds of nitrogen to the state of nitrate was one of the first actions in the soil which was proved to be brought about by bacteria. 1953 Life 8 June 80/2 Known as ‘airglow’, this faint luminescence is emitted by sodium, oxygen and nitrogen molecules and atoms excited by sunlight during the day. 1990 Sunday Express Mag. 15 Apr. 31/3 If there is not enough leafy material around, extra nitrogen can be added in the form of manure, seaweed meal or dried blood. 2006 J. M. Hornback Org. Chem. (Internat. Student ed.) x. 366 Iodomethane and similar reagents can act as carcinogens by alkylating the nitrogens in the bases of DNA. 2. A nitrogen compound, esp. one used as a fertilizer. ΚΠ 1870 Chem. News 14 Oct. 184/1 The nitrogens are..pretty near the theoretical quantities. 1932 Amer. Jrnl. Surg. 15 477/2 Out of 36 cases of alkalosis, 9 had elevated non-protein nitrogens in the blood. 1957 M. Lamer World Fertilizer Econ. ix. 140 Agricultural demand for nitrogenous fertilizers was high enough, and the preference for some of the other nitrogens strong enough. 2013 Press & Jrnl. (Aberdeen) (Nexis) 13 May 8 You need to understand the growing aspects of the [grain] crop so you get the nitrogens, grain size and other specifications required. Compounds C1. a. nitrogen compound n. ΚΠ 1846 Littell's Living Age 17 Oct. 120/2 A cotton is prepared, by a process not yet divulged—but which is in all probability one that depends on the formation of a nitrogen compound. 1932 G. D. Fuller & H. S. Conard tr. J. Braun-Blanquet Plant Sociol. viii. 236 The nitrogen compounds in the soil must generally be converted into nitric acid. 1991 Independent 1 Nov. 17/3 Whether the released, inorganic, nitrogen compounds run off and pollute, or are taken up by crops, depends partly on rainfall. nitrogen gas n. ΚΠ 1791Nitrogene gas [see sense 1]. 1803 F. Accum Syst. Theoret. & Pract. Chem. I. 139 One of the most remarkable combinations into which nitrogen is known to enter, is that which takes place between it and light and caloric. The compound thus produced is called nitrogen gas. 1945 Science 12 Jan. 42/2 The International Standard..after complete desiccation shall be sealed in three containers in pure dry nitrogen gas. 1991 Acta Metallurgica et Materialia 39 2519/2 The solutions were continuously deaerated during experiments by bubbling of purified nitrogen gas. b. nitrogen-collecting adj. ΚΠ 1894 Field 9 June 844/2 The nitrogen-collecting power of leguminous crops. 1901 Bull. Torrey Bot. Club 28 528 It appears that we must add palms to the Leguminosae, Podocarpus, Alnus, and Cycas as plants which have, as it were, domesticated nitrogen-collecting soil organisms. nitrogen-containing adj. ΚΠ 1855 J. P. Norton Elements Sci. Agric. 140 When these substances are subjected to chemical analysis, they are proved to belong to the same class, and to have a composition agreeing, with that of the nitrogenous or nitrogen-containing bodies of the plant. 1898 B. P. Colton Physiol. vi. 161 Urea is the nitrogen-containing waste. 1994 Sci. Amer. Mar. 64/3 Protein and other nitrogen-containing compounds. C2. nitrogen balance n. the relationship between the amounts of nitrogen entering and leaving a biological system; spec.: (a) Physiology the difference between the amounts of nitrogen taken in and excreted by an organism; (b) Soil Science the difference between the amount of nitrogen added to a soil (by fertilization, nitrogen fixation, etc.) and the amount removed (by cropping, leaching, denitrification, etc.). ΚΠ 1897 Science 24 Dec. 949/1 The administration of thyroid tablets was stopped, and..the nitrogen balance became positive immediately and the body weight increased rapidly. 1942 Science 31 July 97/1 Karraker has published reports on these and other phases of the nitrogen balance in soils since 1925. 1988 P. W. Kuchel et al. Schaum's Outl. Theory & Probl. Biochem. xv. 411 The amount of protein (or fixed nitrogen) we ingest determines the state of nitrogen balance. 1993 Appl. & Environmental Microbiol. 59 3026/1 Nitrogen fixation by free-living N₂ fixers..makes a significant contribution to the nitrogen balance of desert grassland communities. nitrogen cycle n. Biology the cycle of changes whereby nitrogen is interconverted between its free state in the air and combined states in organisms and the soil. ΘΚΠ the world > life > biology > balance of nature > environment or habitat > [noun] > sulphur or nitrogen cycle nitrogen cycle1906 sulphur cycle1967 1906 Science 12 Jan. 576/1 River waters differ from pond, lake of reservoir, waters in the essential particular that the former are in rapid motion and the so-called nitrogen cycle may take place several times during the course of their flow. 1966 McGraw-Hill Encycl. Sci. & Technol. (rev. ed.) IX. 111/2 The nitrogen cycle comprises the processes of ammonification, nitrification, denitrification, and nitrogen fixation. 1984 N. N. Greenwood & A. Earnshaw Chem. of Elements (1986) xi. 469 The continuous interchange of nitrogen between the atmosphere and the biosphere is called the nitrogen cycle. nitrogen dioxide n. †(a) nitric oxide, NO, erroneously assigned the formula N₂O₂ (obsolete); (b) a poisonous and reactive brown gas, NO₂, which below 140°C exists in a temperature-dependent equilibrium with nitrogen tetroxide (increasing amounts of the latter being formed on cooling), and which is used in nitric acid production and as a nitrating and oxidizing agent. ΚΠ 1844 G. Fownes Man. Elem. Chem. 114 Deutoxide, or binoxide of nitrogen.] 1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vi. 58 (table) Nitrogen Di-oxide containing 28 parts by weight of N. to 32—O. 1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vi. 72 Nitrogen Dioxide, or Nitric Oxide. 1925 Ann. Missouri Bot. Garden 12 368 In several cases there was a visible evolution of nitrogen dioxide fumes. 1950 Effects of Atomic Weapons (Los Alamos Sci. Lab.) ii. 30 The brownish or peachlike tint of the cloud which has been reported..is apparently due to nitrogen dioxide. 1990 D. F. Shriver et al. Inorg. Chem. xii. 380 Nitrogen( iv) oxide, commonly nitrogen dioxide, exists as an equilibrium mixture of the brown NO₂ radical and its colorless dimer N₂O₄. nitrogen fixation n. the conversion, esp. by bacteria, of gaseous nitrogen into a combined form that is usable by plants. ΘΚΠ the world > life > biology > biological processes > metabolism > [noun] > metabolic processes metastasis1861 respiration1882 nitrogen fixation1893 turn-over1943 the world > matter > chemistry > chemical reactions or processes > [noun] > chemical reactions or processes (named) > fixation > of nitrogen fixation1850 nitrogen fixation1893 1893 Amer. Naturalist 27 1053 The germ theories of fermentation, of nitrification, of sewage filtration, of nitrogen fixation, of the etiology of contagious diseases..are monumental witnesses of the value of this department in the realm of pure science. 1938 Nature 12 Nov. 878/1 Diverse workers..have previously affirmed nitrogen fixation by Blue-green Algæ. 1970 Sunday Times 16 Aug. (Colour Suppl.) 13/1 It is likely that Germany would have collapsed before 1918 but for the nitrogen fixation plants built in 1914–16. nitrogen fixer n. an organism which brings about nitrogen fixation. ΘΚΠ the world > life > biology > balance of nature > organisms in relation to habitat > [noun] colonist1839 benthos1891 land form1897 heterotroph1900 autotroph1901 epibenthos1902 specialist1902 microaerophile1903 nitrifier1903 consumer1904 nitrogen fixer1904 producer1904 indicator1906 psychrophile1906 thermophil1909 sulphuretum1925 influent1926 halobiont1928 halophile1928 mesophile1928 oligosaprobe1931 saprobe1932 eurytope1938 stenotope1938 photoautotroph1939 chemoautotroph1943 prototroph1946 mixotrophy1948 chemolithoautotroph1949 auxotroph1950 chemoheterotroph1951 chemoorganotroph1953 chemolithotroph1955 chemotroph1958 osmophile1961 psychrotroph1963 saprotroph1963 generalist1964 opportunist1967 cryophile1970 1904 Science 30 Sept. 433/1 The legume bacteria are nitrogen fixers without any aid from leguminous plants. 1932 G. D. Fuller & H. S. Conard tr. J. Braun-Blanquet Plant Sociol. viii. 235 Anaerobic and aerobic nitrogen fixers often occur associated together in the same soil. 1997 Internat. Jrnl. Plant Sci. 158 828/1 Spartium junceum is a nitrogen-fixer, and both leaf and stem photosynthesis are inhibited if tissue nitrogen levels drop appreciably. nitrogen-fixing adj. of, relating to, or bringing about nitrogen fixation. ΘΚΠ the world > life > biology > biological processes > metabolism > [adjective] > processes metastatic1880 nitrogen-fixing1890 1890 Proc. Royal Soc. 1889–90 47 113 The development of the supposed nitrogen-fixing organisms obviously depends on the infection of the soil with the organism essential to symbiotic life with the particular leguminous crop to be grown. 1929 J. E. Weaver & F. E. Clements Plant Ecol. x. 249 Both nitrifying and nitrogen-fixing bacteria thrive in the humus. 1966 New Statesman 2 Dec. 826/1 The first new component isolated from the Du Pont nitrogen-fixing system. 1991 Garbage Jan. 45/2 Bailey's acacia (Acacia baileyana), a nitrogen-fixing leguminous type from Australia, is one of the most drought-tolerant trees available. nitrogen monoxide n. (a) = nitrous oxide n. at nitrous adj. and n. Compounds (rare); (b) = nitric oxide n. at nitric adj. Compounds. ΘΚΠ the world > matter > chemistry > chemical substances > named gases > [noun] > containing nitrogen nitrous gas1742 nitrous air1772 nitric oxide1789 nitrogen monoxide1869 nitrox1982 the world > matter > chemistry > chemical substances > named gases > [noun] > containing nitrogen > nitrous oxide nitrous oxide1799 laughing gas1819 nitrogen monoxide1869 nitrous1977 1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vii. 69 The salt decomposes on heating into nitrogen monoxide and water. 1922 T. M. Lowry Inorg. Chem. xxvi. 401 (note) Nitric oxide (or nitrogen monoxide)... This [latter] name is sometimes applied loosely to dinitrogen monoxide, N₂O, and is therefore too ambiguous to be used safely. 1992 Science 18 Dec. 1898/1 Nitrogen monoxide (NO) has been implicated in a number of diverse physiological processes. nitrogen mustard n. any of a class of compounds containing the group —N(CH₂CH₂Cl)₂ (a side chain similar to the mustard gas molecule), which have alkylating properties and are cytotoxic, some being used to treat cancers. ΘΚΠ the world > health and disease > healing > medicines or physic > medicines for specific purpose > preparations treating or preventing specific ailments > [noun] > for tumour platinum blue1908 nitrogen mustard1943 mustard1945 piperoxan1950 melphalan1960 procarbazine1965 bleomycin1966 1943 Science 24 Dec. 10/2 New war gases, nitrogen mustards, were developed and found to have a milder blistering action than mustard gas and to cause blindness. 1970 R. Passmore & J. S. 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. 1991 New Scientist 31 Aug. 20/1 They use so-called nitrogen mustard as the cell-killing, or cytotoxic, component. nitrogen narcosis n. a narcotic state which is induced by breathing air under pressure and occurs esp. in divers. ΘΚΠ the world > health and disease > ill health > a disease > disorders of internal organs > stupor or coma > [noun] > specific coma coma vigil1708 hydrocephaloid disease1842 nitrogen narcosis1937 insulin coma1942 rapture of the deep1953 narks1962 1937 U.S. Naval Med. Bull. 35 379 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. 1962 Listener 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. 1990 Alert Diver May 3 Much is still unknown about decompression sickness, oxygen toxicity, and nitrogen narcosis. nitrogen oxide n. each of the seven oxides of nitrogen; spec. any one or a mixture of these oxides released into the environment as a result of fuel combustion (esp. nitric oxide, NO, and nitrogen dioxide, NO₂). ΚΠ 1868 H. B. Jones & H. Watts Fownes's Man. Elem. Chem. (ed. 10) 158 The other three nitrogen oxides do not form salts. 1957 Rep. Air Pollution Foundation (U.S.) No. 21. 1 It is now realised that Los Angeles' smog is primarily a reaction between organic matter and nitrogen oxides in the presence of sunlight. 1990 Sci. Amer. May 59/1 The Clean Air Act of 1970, soon to be amended, limits the hydrocarbon, carbon monoxide and nitrogen oxide emissions that are permitted in tail-pipe exhaust. nitrogen pentoxide n. a colourless solid, N₂O₅ (or NO₂⁺.NO₃⁻), which is a strong oxidizing agent that reacts with water to form nitric acid (also called dinitrogen pentoxide). ΚΠ 1869 H. E. Roscoe Lessons Elem. Chem. (new ed.) vi. 63 Nitric acid may be considered as a compound of nitrogen pentoxide with water. 1922 Science 17 Nov. 577/1 The decomposition of nitrogen pentoxide..is a unimolecular, gas phase reaction which takes place at room temperature. 1993 New Phytologist 124 268/1 Ozone generated by electric discharge from the air may be contaminated by nitrogen compounds, e.g. nitrogen pentoxide. nitrogen peroxide n. nitrogen dioxide and nitrogen tetroxide, considered as a single substance in two forms. ΚΠ 1842 T. Graham Elements Chem. 282 Peroxide of Nitrogen (nitrous acid of Turner, hyponitric acid of Thenard)..NO₄.] 1874 Index Jrnl. Chem. Soc. 198/1 Nitrogen peroxide. See Nitrogen Tetroxide. 1955 B. C. L. Kemp Elem. Org. Chem. (new ed.) x. 152 The oxidizing action of concentrated nitric acid is catalysed by the presence of nitrogen peroxide (NO₂). 1996 Milling & Baking News (Nexis) 3 Dec. 34 The earliest attempts were made in the United Kingdom, using ozone as the bleaching agent. Nitrogen peroxide was next used. nitrogen tetroxide n. a colourless volatile liquid, N₂O₄, which exists in temperature-dependent equilibrium with nitrogen dioxide, and is used as a nitrating agent, a solvent, and an oxidizer in rocket fuels (also called dinitrogen tetroxide). ΚΠ 1866 H. E. Roscoe Lessons Elem. Chem. vi. 53 Nitrogen tetroxide containing 28 parts by weight of N. to 64 of O. 1969 Times 3 June (Suppl.) p. iii/7 All three systems were propelled by nitrogen tetroxide. 1994 N.Y. Times 11 Jan. c11/1 An investigating panel..said that a small amount of liquid nitrogen tetroxide, about two tablespoons, probably leaked during the long cold journey and condensed upstream. nitrogen trichloride n. a pungent, explosive yellow oil, NCl₃, made by reaction of ammonia with excess chlorine and formerly used to bleach and age flour. ΚΠ 1889 I. Remsen Inorg. Chem. xvii. 292 According to this, the trichloride of nitrogen is the final product of the substituting action of chlorine upon ammonia.] 1896 Science 3 July 28/2 They show an analogy to nitrogen trichloride in their instability. 1947 Lancet 23 Aug. 284/1 Acceptibility of bread as an article of food is largely increased by the use of an ‘improver’... The one in most extensive use in this country..is nitrogen trichloride: known commercially as ‘agene’. 1988 F. A. Cotton & G. Wilkinson Adv. Inorg. Chem. (ed. 5) x. 331 Nitrogen trichloride..is formed in the chlorination of the slightly acid solutions of NH₄Cl. nitrogen trioxide n. (a) the anhydride of nitrous acid, N₂O₃, which is a blue liquid (made greenish by dissolved nitrogen dioxide) which decomposes above 3.5°C (also called dinitrogen trioxide); (b) an unstable gaseous oxide of nitrogen, NO₃, identified chiefly by its absorption spectrum. ΚΠ 1868 H. B. Jones & H. Watts Fownes's Man. Elem. Chem. (ed. 10) 161 Nitrogen trioxide, or nitrous oxide... A mobile blue liquid, which emits orange-red vapors. 1936 Jrnl. Chem. Soc. 1412 When ozonized oxygen is passed over nitric anhydride, a gas with a blue tint is produced, which probably contains nitrogen trioxide, NO₃. 1938 R. Hum Chem. for Engin. Students xv. 362 Nitrogen trioxide [N₂O₃]..is obtained as a blue liquid when a mixture of nitric oxide and nitrogen peroxide is passed through a U-tube immersed in a freezing mixture at −30°C. 1966 Proc. Royal Soc. A. 295 82 It appears that under these conditions, nitrogen trioxide, if formed, reacts almost entirely with nitric oxide rather than with sulphur dioxide. This entry has been updated (OED Third Edition, December 2003; most recently modified version published online March 2022). < n.1791
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