urean.

Brit.

/jᵿˈriːə/, U.S.

/jʊˈriə/

Etymology: < (with Latinized ending) French urée (1803), < Greek οὖρον urine, or the verb οὐρέω. Compare Italian urea, Spanish urea, Portuguese urea.

Chemistry.

a. A soluble crystalline compound, forming an organic constituent of the urine in mammalia, birds, and some reptiles, and also found in the blood, milk, etc.; carbamide, CO(NH₂)₂.

ΘΚΠ

the world > matter > chemistry > organic chemistry > substances from animals or humans > urea > [noun]

urea1806

1806 Philos. Trans. (Royal Soc.) 96 374 A decomposition of a portion of urea.

1819 W. T. Brande Man. Chem. 446 Urea is the principle which confers upon urine its chief peculiarities.

1862 T. H. Huxley On Knowl. Causes Phenomena Org. Nature 72 Urea..forms one of the waste products of animal structures.

1878 C. T. Kingzett Animal Chem. 190 Urea was discovered by Boerhaave before 1720, and was called by him the essential salt of urine.

b. A urea-formaldehyde plastic or resin.

ΘΚΠ

society > occupation and work > materials > derived or manufactured material > synthetic resins and plastics > [noun] > types of

phenolic1935

urea1935

melamine1940

1935 Economist 7 Dec. 1142/2 Phenolic plastics are used for various mouldings, urea is translucent plastic.

1961 H. R. Symonds Source Bk. New Plastics II. ii. 32 A new urea especially prepared for the bonding of particle board.

1969 L. K. Arnold Introd. Plastics vi. 83 The ureas are somewhat more expensive [than the phenolics] but have the advantage of being available in a wide range of light colors.

Compounds

C1. General attributive.

urea excretion n.

ΚΠ

1897 T. C. Allbutt et al. Syst. Med. IV. 292 Observations on the urea excretion.

urea-formation n.

ΚΠ

1897 T. C. Allbutt et al. Syst. Med. IV. 72 Pointing to the liver as the chief seat of urea-formation.

urea-residue n.

ΚΠ

1866 W. Odling Lect. Animal Chem. 129 The assumption of pre-existent urea-residues in uric acid.

C2.

urea-formaldehyde n. used attributively and absol. to designate plastics, resins, etc., made by condensation of urea with formaldehyde.

ΘΚΠ

society > occupation and work > materials > derived or manufactured material > synthetic resins and plastics > [adjective] > type of synthetic resin or plastic

urea-formaldehyde1928

polyvinyl1933

1928 Brit. Patent 291,473 3/2 When using urea-formaldehyde resins, alkaline catalysts may be used to obtain the intermediate condensation product.

1933 Archit. Rev. 73 1 The synthetic plastics of which the two best known and most fully developed are the Phenol-formaldehyde and the Urea-formaldehyde types.

1976 Milton Keynes Express 9 July 14/4 The majority of houses have cavity walls and these can be insulated by filling the cavity with..a foaming resin called urea formaldehyde.

1984 Christian Sci. Monitor 2 Mar. 23/1 The safety of urea-formaldehyde insulation..has been a subject of debate for years.

urea nitrate n. (see quots. 1873 for urea oxalate n.).

ΚΠ

1873 C. H. Ralfe Outl. Physiol. Chem. 83 Urea nitrate (CN₂H₄O,HNO₃): the crystals form shining, rhombic plates.

urea oxalate n. (see quots. 1873).

ΚΠ

1873 C. H. Ralfe Outl. Physiol. Chem. 83 Urea oxalate (2CN₂H₄O,C₂H₂O₄): the crystals form long, transparent, tufted laminæ.

urea resin n. a synthetic resin derived from urea; a urea-formaldehyde resin.

ΘΚΠ

society > occupation and work > materials > derived or manufactured material > synthetic resins and plastics > [noun] > synthetic resin > specific synthetic resins

coumarone resin1900

novolak1909

glyptal1915

marblette1927

Vinylite1929

polyolefin1930

polysulphone1934

urea resin1937

melamine resin1939

polyurethane1939

polyvinylidene chloride1940

polyvinyl butyral1941

polyimide1945

Teflon1945

Araldite1946

polytetrafluoroethylene1946

epoxy resin1950

urethane1956

Maraglas1962

tartan1964

alkyd1984

1937 R. S. Morrell et al. Synthetic Resins ii. 52 Tootal, Broadhurst, Lee Company Limited have patented the use of urea resins to prevent the crushing of cellulosic fabrics.

1975 M. P. Stevens Polymer Chem. xii. 329 Decorative interior plywood is normally glued with urea resin because the dark-colored phenolic resins can stain the veneer.

This entry has not yet been fully updated (first published 1926; most recently modified version published online December 2021).

单词	urea
释义	urean. Brit. /jᵿˈriːə/, U.S. /jʊˈriə/ Etymology: < (with Latinized ending) French urée (1803), < Greek οὖρον urine, or the verb οὐρέω. Compare Italian urea, Spanish urea, Portuguese urea. Chemistry. a. A soluble crystalline compound, forming an organic constituent of the urine in mammalia, birds, and some reptiles, and also found in the blood, milk, etc.; carbamide, CO(NH₂)₂. ΘΚΠ the world > matter > chemistry > organic chemistry > substances from animals or humans > urea > [noun] urea1806 1806 Philos. Trans. (Royal Soc.) 96 374 A decomposition of a portion of urea. 1819 W. T. Brande Man. Chem. 446 Urea is the principle which confers upon urine its chief peculiarities. 1862 T. H. Huxley On Knowl. Causes Phenomena Org. Nature 72 Urea..forms one of the waste products of animal structures. 1878 C. T. Kingzett Animal Chem. 190 Urea was discovered by Boerhaave before 1720, and was called by him the essential salt of urine. b. A urea-formaldehyde plastic or resin. ΘΚΠ society > occupation and work > materials > derived or manufactured material > synthetic resins and plastics > [noun] > types of phenolic1935 urea1935 melamine1940 1935 Economist 7 Dec. 1142/2 Phenolic plastics are used for various mouldings, urea is translucent plastic. 1961 H. R. Symonds Source Bk. New Plastics II. ii. 32 A new urea especially prepared for the bonding of particle board. 1969 L. K. Arnold Introd. Plastics vi. 83 The ureas are somewhat more expensive [than the phenolics] but have the advantage of being available in a wide range of light colors. Compounds C1. General attributive. urea excretion n. ΚΠ 1897 T. C. Allbutt et al. Syst. Med. IV. 292 Observations on the urea excretion. urea-formation n. ΚΠ 1897 T. C. Allbutt et al. Syst. Med. IV. 72 Pointing to the liver as the chief seat of urea-formation. urea-residue n. ΚΠ 1866 W. Odling Lect. Animal Chem. 129 The assumption of pre-existent urea-residues in uric acid. C2. urea-formaldehyde n. used attributively and absol. to designate plastics, resins, etc., made by condensation of urea with formaldehyde. ΘΚΠ society > occupation and work > materials > derived or manufactured material > synthetic resins and plastics > [adjective] > type of synthetic resin or plastic urea-formaldehyde1928 polyvinyl1933 1928 Brit. Patent 291,473 3/2 When using urea-formaldehyde resins, alkaline catalysts may be used to obtain the intermediate condensation product. 1933 Archit. Rev. 73 1 The synthetic plastics of which the two best known and most fully developed are the Phenol-formaldehyde and the Urea-formaldehyde types. 1976 Milton Keynes Express 9 July 14/4 The majority of houses have cavity walls and these can be insulated by filling the cavity with..a foaming resin called urea formaldehyde. 1984 Christian Sci. Monitor 2 Mar. 23/1 The safety of urea-formaldehyde insulation..has been a subject of debate for years. urea nitrate n. (see quots. 1873 for urea oxalate n.). ΚΠ 1873 C. H. Ralfe Outl. Physiol. Chem. 83 Urea nitrate (CN₂H₄O,HNO₃): the crystals form shining, rhombic plates. urea oxalate n. (see quots. 1873). ΚΠ 1873 C. H. Ralfe Outl. Physiol. Chem. 83 Urea oxalate (2CN₂H₄O,C₂H₂O₄): the crystals form long, transparent, tufted laminæ. urea resin n. a synthetic resin derived from urea; a urea-formaldehyde resin. ΘΚΠ society > occupation and work > materials > derived or manufactured material > synthetic resins and plastics > [noun] > synthetic resin > specific synthetic resins coumarone resin1900 novolak1909 glyptal1915 marblette1927 Vinylite1929 polyolefin1930 polysulphone1934 urea resin1937 melamine resin1939 polyurethane1939 polyvinylidene chloride1940 polyvinyl butyral1941 polyimide1945 Teflon1945 Araldite1946 polytetrafluoroethylene1946 epoxy resin1950 urethane1956 Maraglas1962 tartan1964 alkyd1984 1937 R. S. Morrell et al. Synthetic Resins ii. 52 Tootal, Broadhurst, Lee Company Limited have patented the use of urea resins to prevent the crushing of cellulosic fabrics. 1975 M. P. Stevens Polymer Chem. xii. 329 Decorative interior plywood is normally glued with urea resin because the dark-colored phenolic resins can stain the veneer. This entry has not yet been fully updated (first published 1926; most recently modified version published online December 2021). > see also also refers to : urea-comb. form < n.1806 see also
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urean.

Compounds

> see also