| 释义 |
fugacity|fjuːˈgæsɪtɪ|
[f. as prec. + -ty.]
The quality of being fugacious; instability; transitoriness. Of a material substance: Volatility.
1656Blount Glossogr., Fugacity, a readiness to run away, inconstancy, an inclination to flight. 1666Boyle Orig. Formes & Qual. 190 By our Experiment, its Fugacity is so restrain'd, that..the Caput mortuum..endured a good fire in the Retort. 1751Johnson Rambler No. 143 ⁋3 The deceitfulness of hope, the fugacity of pleasure, the fragility of beauty. 1807F. Wrangham Serm. Transl. Script. 31 Considerations of the fugacity of time. 1830Lindley Nat. Syst. Bot. 288 The acrid principle..notwithstanding its fugacity, has been lately obtained pure. 1841–44Emerson Ess., Poet (1885) II. 321 The accidency and fugacity of the symbol. 1868Bushnell Serm. Liv. Subj. 281 The fugacities are left behind us.
Comb.1894Brit. Jrnl. Photog. XLI. 68 The fugacity-producing quality of this bath.
Add:2. Physical Chem. A thermodynamic property of a (real) gas which is defined in such a way that substituting it for the pressure or partial pressure in the equations for an ideal gas gives equations applicable to the real gas; a thermodynamic property of a liquid or solid defined by the same function, µ = RT ln f + µ0 (where µ is the chemical potential, T the temperature, f the fugacity, and µ0 is a function of temperature only). See also oxygen fugacity s.v. *oxygen n. 3 b.
1902G. N. Lewis in Proc. Amer. Acad. Arts & Sci. XXXVII. 54 Every molecular species may be considered..to have a tendency to escape from the phase in which it is. In order to express this tendency quantitatively for any particular state,..the quantity which we shall use..will be called the fugacity. 1915[see disperse v. 9]. 1949J. R. Partington Adv. Treat. Physical Chem. I. vii. 721 Fugacities in mixtures may be calculated on the assumption that the fugacity is equal to the mol fraction times the fugacity of the pure gas at the same temperature and total pressure. 1969K. H. Wedepohl et al. Handbk. Geochem. I. iii. 41 Fugacity has..a wider meaning, applicable to solids and liquids as well as gases. It is most easily visualized as a vapor pressure, or more precisely the vapor pressure a substance would exert if its vapor behaved as a perfect gas. 1986Scripta Metallurgica XX. 654 The formation of blisters at the Al–Al2O3 interface upon exposure to the gaseous H2 ..provides a means of estimating the hydrogen fugacity in the environmental cell under the electron beam.
3. Special comb.: fugacity coefficient Physical Chem., the ratio of fugacity to pressure for a particular gas.
1949Redlich & Kwong in Chem. Rev. XLIV. 237 It is convenient to call the quotient of the fugacity and the pressure ‘fugacity coefficient’. 1966Industr. & Engin. Chem. (Fund.) Nov. 455/1 Three methods of calculating fugacity coefficients in multicomponent mixtures..take into account abnormal interaction effects between unlike molecules by utilizing binary mixture data. 1984J. Pennington in C. A. Heaton Introd. Industr. Chem. viii. 283 At higher pressures the fugacities of components must be obtained from published data or by applying a ‘fugacity coefficient’, ϕ = f/p, derived from a generalized chart. |