| 释义 |
▪ I. gel, n.|dʒɛl|
[Orig. a suffix f. the first syllable of gelatin (as in alcogel, hydrogel) and later used as an independent word.]
1. Chem. A semi-solid colloidal system consisting of a solid dispersed in a liquid. Also attrib.
The invention of this word and of sol is ascribed by later writers to Thomas Graham (died 1869).
1899W. B. Hardy in Jrnl. Physiol. XXIV. 164 Graham's nomenclature is as follows: The fluid state, colloidal solution, is the ‘sol’, the solid state the ‘gel’. The fluid constituent is indicated by a prefix. Thus an aqueous solution of gelatine is a ‘hydrosol’, and on setting it becomes a ‘hydrogel’. 1904W. C. D. Whetham Recent Devel. Phys. Sci. iv. 137 The mass will solidify under certain conditions to form a solid which may be called a gel. 1918Nature 28 Mar. 66/1 A very minute amount of electrolyte added to a stable colloidal solution may bring about complete precipitation or flocculation of the sol, the sol separating out in a gelatinous form known as a gel. 1922Encycl. Brit. XXX. 591/1 On digestion with water the cellular tissue is transformed into a series of hydrated gel-products. 1926Ibid. Suppl. I. 785 The Brownian movement affords a criterion of whether protoplasm is in the condition of a sol or a gel. 1930Engineering 31 Jan. 142/3 Cement could be regarded as what in colloid chemistry is known as a rigid gel, which changes its physical properties..according to the variations of its moisture content. 1930Nature 15 Mar. 432 Structure in very permeable collodion gel films and its significance in filtration problems. 1931Oxf. Univ. Gaz. 17 June 693/2 The equilibria between (a) silica gel and water vapour, (b) silica gel and alcohol vapour, (c) iron oxide gel and alcohol. 1951Williams & Alberty in Taylor & Glasstone Treat. Physical Chem. (ed. 3) II. v. 675 There is at present almost universal acceptance of the view that gels possess a ramifying, more or less coherent, framework that retains the liquid component and confers elasticity and rigidity upon the system as a whole. 1966McGraw-Hill Encycl. Sci. & Technol. VI. 93/1 Commonly, gels have a low solid content, for example, 2–5% for ferric oxide, and as little as 0·1% for coagulated blood.
2. Hairdressing. A jelly-like substance used for setting or styling the hair, sold as a jelly.
1958Amer. Hairdresser July 26/1 (Advt.), Contains miracle deprovinyllol/DEP/styling gel. Ibid. 26/1 DEP..Not a spray{ddd}not a liquid. DEP is a silky gel. 1968Trade Marks Jrnl. 11 Sept. 1518/1 Trugel..Preparations for the hair, all in gel form. Nicholas Products Limited, 225 Bath Road, Slough, Buckinghamshire; Manufacturers and Merchants.—2nd March, 1967. 1975Chem. Week 26 Mar. 37/1 Beauty salon hair dressers and cosmeticians expect women to go in for fancier coiffures..which..will increase sales of chemical specialty products, such as permanent waves, hair-setting lotions and gels. 1984Daily Mail 20 Oct. 12/2 Hair is expensively highlighted—blown and brushed back and worked over with gels.
Add:3. Special Comb. gel electrophoresis Biochem., electrophoresis in which a gel of an organic polymer such as polyacrylamide or agarose is used as a medium for the separation of macromolecules.
1955Biochem. Jrnl. LXI. 635/1 α1-Globulin does not appear as a definite band between α2-globulin and albumin in starch *gel electrophoresis. 1982T. M. Devlin Textbk. Biochem. iii. 114/1 The hyperlipoproteinemias are classified..according to the abnormal pattern observed in plasma lipoprotein gel electrophoresis. 1991Saudi Med. Jrnl. XII. 287/2 Karyotyping..is carried out using pulsed field or field inversion gel electrophoresis.
▪ II. gel, v.|dʒɛl|
[f. the n.]
intr. To become a gel. fig. = jell v. (fig.). Hence gelled ppl. a., ˈgelling vbl. n.
1917Sci. Amer. Suppl. 22 Sept. 191/2 Ligno-cellulose fibre..does not gel so readily by cold mechanical treatment as does cellulose. 1924H. B. Weiser in R. H. Bogue Theory & Applic. Colloidal Behavior I. xv. 390 A sol containing 1 per cent of pure gelatin does not gel until around 10°. 1933Fischer & Hooker Lyophilic Colloids i. ix. 159 These explanations..do nothing to make clear why the silicic acid so frequently gels before being precipitated, or the relationship of the gelling process to the precipitation. 1953Kirk & Othmer Encycl. Chem. Technol. XI. 162 It causes the ink to body up and finally to gel completely. 1970Nature 25 July 371/1 The mixture gelled at T0 °C. After 5 h..the cell was warmed a few degrees to make the gelled oil transparent.
fig.1958Observer 30 Mar. 14/3 The combination of drawingroom and documentary failed to gel. 1966Listener 14 Apr. 549/1, I recognize the moment As when an awareness gels. |