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INDEX thermodynamic functions

The micelle formation process and structure can be described by thermodynamic functions (AG°mjc, AH°mjc, AS°mic), physical parameters (surface tension, conductivity, refractive index) or by using techniques such NMR spectroscopy, fluorescence spectroscopy, small-angle neutron scattering and positron annihilation. Experimental data show that the dependence of the aggregate nature, whether normal or reverse micelle is formed, depends on the dielectric constant of the medium (Das et al., 1992 Gon and Kumar, 1996 Kertes and Gutman, 1976 Ward and du Reau, 1993). The thermodynamic functions for micellization of some surfactants are presented in Table 1.1. [Pg.4]

The relation of fluctuations in concentration to thermodynamic functions was also previously recognized in the theory of light scattering from solutions (Brinkman and Hermans 1949 Kirkwood and Goldberg 1950 Stockmayer 1950) since light is scattered by inhomogeneities in refractive index, which, in turn, arise in part from concentration fluctuations. [Pg.376]

This review contains critically evaluated values of the vapor pressure, heat capacity, enthalpies of transition, entropies, thermodynamic functions for the real and ideal gases, densities, refractive indexes, and critical properties for 722 alcohols in the carbon range Cj to Cjo- This comprehensive review is 420 pages long and lists 2036 references. [Pg.811]

MFLG DESCRIPTION OF BINARY SYSTEMS A two component system is in the MFLG approximation treated as a pseudo-ternary mixture of constituents 1, 2 and holes (index 0). The appropriate thermodynamic function for the description of fluid phase equilibria is the Helmholtz free energy of mixing vacant and occupied sites, and reads in the simplest version of the model ). [Pg.76]

The exponent t), along with the exponents we already took note of in 9.1 and others that we shall introduce, describe the analytic form of thermodynamic functions and correlation functions near the critical point, and, in particular, index the critical-point singularities of those functions. In 9.3 we shall see how the many critical-point exponents are related to each other, and what their values are, both in the classical, mean-field theories and in reality. [Pg.261]

In order to avoid complex notations the index hn is omitted from the molar thermodynamic functions. Thus AG, AH, AS refer to 1 mol if not stated otherwise. [Pg.277]

As in energy representation the fundamental thermodynamic equation in entropy representation (3) may also be subjected to Legendre transformation to generate a series of characteristic functions designated as Massieu-Planck (MP) functions, m. The index m denotes the number of intensive parameters introduced as independent variables, i.e. [Pg.483]

Here, index i and parameter are substituted for by index a and parame ter Ao(, which is always allowed for monomolecular processes. Thus, the functional O derivative with respect to thermodynamic rush of an inter mediate is proportional to the rate of this intermediate concentration changes everywhere, even far from thermodynamic equihbrium. For this reason, in the state stationary with respect to the intermediate concentra tion, this derivative turns zero (cf the case of the Rayleigh Onsager functional). [Pg.128]

In another work, Poteau et al.61 studied the temperature-dependent properties of the Na clusters using a tight-binding model together with a Monte Carlo thermodynamic method (cf. Section 2.2). By studying the Lindemann index [Eq. (60)] as a function of temperature they could identify phase-transition temperatures, although, as also seen by analysing the heat capacity and the moments of inertia as functions of temperature, these transitions are not sharp. [Pg.287]

The formalism of the statistical mechanics agrees with the requirements of the equilibrium thermodynamics if the thermodynamic potential, which contains all information about the physical system, in the thermodynamic limit is a homogeneous function of the first order with respect to the extensive variables of state of the system [14, 6-7]. It was proved that for the Tsallis and Boltzmann-Gibbs statistics [6, 7], the Renyi statistics [10], and the incomplete nonextensive statistics [12], this property of thermodynamic potential provides the zeroth law of thermodynamics, the principle of additivity, the Euler theorem, and the Gibbs-Duhem relation if the entropic index z is an extensive variable of state. The scaling properties of the entropic index z and its relation to the thermodynamic limit for the Tsallis statistics were first discussed in the papers [16,17],... [Pg.304]

In the present work, the general mathematical scheme of construction of the equilibrium statistical mechanics on the basis of an arbitrary definition of statistical entropy for two types of thermodynamic potential, the first and the second thermodynamic potentials, was proposed. As an example, we investigated the Tsallis and Boltzmann-Gibbs statistical entropies in the canonical and microcanonical ensembles. On the example of a nonrelativistic ideal gas, it was proven that the statistical mechanics based on the Tsallis entropy satisfies the requirements of the equilibrium thermodynamics only in the thermodynamic limit when the entropic index z is an extensive variable of state of the system. In this case the thermodynamic quantities of the Tsallis statistics belong to one of the classes of homogeneous functions of the first or zero orders. [Pg.329]

This is the defining equation for the fundamental material function Lx, the spectral intensity, it describes the directional and wavelength dependence of the energy radiated by a body and has the character of a distribution function. The (thermodynamic) temperature T in the argument of Lx points out that the spectral intensity depends on the temperature of the radiating body and its material properties, in particular on the nature of its surface. The adjective spectral and the index A show that the spectral intensity depends on the wavelength A and is a quantity per wavelength interval. The Si-units of Lx are W/(m2/um sr). The units pm and sr refer to the relationship with dA and dec. [Pg.508]

Index of Refraction. The refraction of index of a fluid is usually a function of the thermodynamic state, often only the density. According to the Lorenz-Lorentz equation, the relation between the index of refraction and temperature is given by... [Pg.1198]

Certain quantities are defined as the ratios of two quantities of the same kind, and thus have a dimension which may be expressed by the number one. The unit of such quantities is necessarily a derived unit coherent with the other units of the SI and, since it is formed as the ratio of two identical SI units, the unit also may be expressed by the number one. Thus the SI unit of all quantities having the dimensional product one is the number one. Examples of such quantities are refractive index, relative permeability, and friction factor. Other quantities having the unit 1 include characteristic numbers like the Prandtl number and numbers which represent a count, such as a number of molecules, degeneracy (number of energy levels), and partition function in statistical thermodynamics. AU of these quantities are described as being dimensionless, or of dimension one, and have the coherent SI unit 1. Their values are simply expressed as numbers and, in general, the unit 1 is not explicitly shown. In a few cases, however, a special name is given to this unit, mainly to avoid confusion between some compound derived units. This is the case for the radian, steradian and neper. [Pg.29]


See other pages where INDEX thermodynamic functions is mentioned: [Pg.231]    [Pg.149]    [Pg.231]    [Pg.247]    [Pg.33]    [Pg.855]    [Pg.748]    [Pg.6]    [Pg.28]    [Pg.450]    [Pg.300]    [Pg.3]    [Pg.750]    [Pg.35]    [Pg.45]    [Pg.271]    [Pg.13]    [Pg.129]    [Pg.127]    [Pg.11]    [Pg.236]    [Pg.49]    [Pg.271]    [Pg.43]    [Pg.226]    [Pg.302]    [Pg.110]    [Pg.323]    [Pg.344]    [Pg.194]    [Pg.541]    [Pg.370]    [Pg.35]    [Pg.16]   
See also in sourсe #XX -- [ Pg.378 ]




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