| 释义 |
rheopexy Physical Chem.|ˈriːəpɛksɪ|
[f. rheo- + -pexy.]
The property, possessed by some sols, of undergoing accelerated gelation when subjected to gentle mechanical agitation. Cf. thixotropy. So rheoˈpectic a.
1935Freundlich & Juliusburger in Trans. Faraday Soc. XXXI. 921 It is too cumbrous to say ‘thixotropic sols which can be solidified by orienting the particles’. Graham used the word ‘pectous’..for sols which have turned to a jelly. We therefore propose to call a thixotropic sol, which may be solidified by gentle movement, ‘rheopectic’, and the phenomenon itself ‘rheopexy’. 1958U.S. Patent 2,846,394 1/1 The grease is a rheopectic lubricant composition which essentially comprises an oleaginous base thickened with..a lithium soap of a hydroxy stearic acid. 1963New Scientist 22 Aug. 384/1 The viscosity in the return part of the programme is greater than the viscosity at the same rate of shear in the upward part. This behaviour is called rheopexy. 1967Ibid. 20 July 143/2 The technique is to add to the fuel a high-molecular-weight polymer..which converts the fuel into a ‘rheopectic gel’... Such a fluid undergoes a large change in viscosity and volatility when subjected to shear forces above a certain level. 1978C. J. Geankoplis Transport Processes & Unit Operations ii. 105 In design procedures for thixotropic and rheopectic fluids for steady flow in pipes, the limiting flow-property values at a constant rate of shear are sometimes used. |