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Equilibrium term

Equilibrium terms, multi- Geometries QM, electron diffraction, mi-... [Pg.18]

Substitute the equilibrium terms into the expression for K. This gives an algebraic equation that must be solved for x. [Pg.335]

Although many natural systems are far from equilibrium, many localized regions of natural systems are well described in thermod3mamic and equilibrium terms. As a general rule, if the reactions that redistribute compounds between the reactant and product states are fast, then equilibrium conditions may be applied. In some cases, part of a system can be described in equilibrium terms and part... [Pg.103]

The Brpnsted equations relate a rate eonstant k to an equilibrium constant K. In Chapter 6, we saw that the Marcus equation also relates a rate term (in that case AG ) to an equilibrium term AG°. When the Marcus treatment is applied to proton... [Pg.337]

Step 2 Write the equation for the acid dissociation constant. Substitute equilibrium terms into the equation. [Pg.397]

The book is organized in nine chapters and eleven appendices. Chapters 1 and 2 introduce the fundamental concepts and definitions. Chapters 3 to 7 treat binding systems of increasing complexity. The central chapter is Chapter 4, where all possible sources of cooperativity in binding systems are discussed. Chapter 8 deals with regulatory enzymes. Although the phenomenon of cooperativity here is manifested in the kinetics of enzymatic reactions, one can translate the description of the phenomenon into equilibrium terms. Chapter 9 deals with some aspects of solvation effects on cooperativity. Here, we only outline the methods one should use to study solvation effects for any specific system. [Pg.362]

X can be regarded as the local non-equilibrium distribution of the species a at a position rj. As the system approaches equilibrium, x becomes -small. In a like manner, the doublet density fjf3 can be decomposed into an equilibrium term, two contributions from the local non-equilibrium departures of the particle a and (3 separately and then their mutual effect... [Pg.347]

The sorption coefficient (K) in Equation (2.84) is the term linking the concentration of a component in the fluid phase with its concentration in the membrane polymer phase. Because sorption is an equilibrium term, conventional thermodynamics can be used to calculate solubilities of gases in polymers to within a factor of two or three. However, diffusion coefficients (D) are kinetic terms that reflect the effect of the surrounding environment on the molecular motion of permeating components. Calculation of diffusion coefficients in liquids and gases is possible, but calculation of diffusion coefficients in polymers is much more difficult. In the long term, the best hope for accurate predictions of diffusion in polymers is the molecular dynamics calculations described in an earlier section. However, this technique is still under development and is currently limited to calculations of the diffusion of small gas molecules in amorphous polymers the... [Pg.48]

According to transition-state theory it is possible to consider reaction velocities in terms of a hypothetical equilibrium between reactants and transition state. It follows that the influence of the isotopic composition of the medium on reaction velocity can be considered to be the same as its influence on the concentration of transition states. The kinetic formulation of the problem can thus be replaced by one couched in equilibrium terms, and the equilibrium theory of the preceding section can be applied with a minimum of modification (Kresge, 1964). The rate constant, or catalytic coefficient, (k) for a catalysed reaction can be written as the product of three factors, viz. the equilibrium constant (K ) for the process forming the transition state from the reactants, the transmission coefficient, and the specific rate of transition state decomposition (kT/h). We recognize that the third factor is independent of the isotopic nature of the reaction and assume that there is no isotope effect on the transmission coefficient. It follows that... [Pg.271]

Analogous with the procedure presented before, reactive distillation tines can be obtained by computing a series of dew and bubble points incorporating a chemical equilibrium term, as follows ... [Pg.465]

We can trace this failure to two reasons. First, chain conformations and interactions at molecular and segmental level have not been appropriately taken into consideration. Second -again - the existence of compact bundles has not been realized. While the model we are studying has been constructed essentially in equilibrium terms, its extension to DR and MDF (40) turned out to be successful. To conclude this paper, let us enumerate some of the phenomena related to DR and MDF, explained in terms of the model proposed in (23) and on the basis of our calculations ... [Pg.396]

DNA deoxyribonucleic acid. (Chap. 19, p. 688) double bond a bond formed by the sharing of two pairs of electrons between two atoms. (Chap. 9, p. 321) double displacement a type of reaction where the positive and negative portions of two ionic compounds are interchanged at least one product must be water or a precipitate. (Chap. 6, p. 208) ductile property of a metal that means it can easily be drawn into a wire. (Chap. 9, p. 313) dynamic equilibrium term describing a system in which opposite reactions are taking place at the same rate. (Chap. 6, p. 211)... [Pg.864]

Algebraic constraints, in a number of n are used to represent fast reversible reactions and equilibrium terms like those arising from adsorption phenomena. They will be presented further. is a n -vector of displacement velocities. They are slack variables (2) that have the same unit as r. They can be understood as the velocity by which each specie must vary, while the system is reacting, in order to keep the algebraic equations that expresses equilibrium constraints satisfied, n,. is a n x n matrix which multiplies in order to keep elemental balances satisfied. [Pg.572]

This problem is related to the question, is there a minimum work input required, before dispersion begins to take place Or, in non-equilibrium terms What is the critical parameter and what is its value, at which... [Pg.607]

Denbigh 2 Drickamer and collaborators/ Wirtz, Wirtz and Hiby/ and Prigogine and co-workers have written numerous papers containing molecular interpretations of the heat of transport and the related Soret coefficient in liquids. These have proceeded on the basis of special assumptions concerning the molecular structure of the liquid and the mechanism of the diffusion process, and have assumed the validity of the equilibrium statisticaL mechanical distribution in the nonequilibrium case. In the present paper we remove the special assumptions and show from general statistical mechanics that the heat of transport consists not only of an equilibrium term but also a term which arises from the nonequilibrium perturbation to the distribution function. In the special case of a regular solution, the expression for the equilibrium... [Pg.1]

In an arbitrage-free model, the initial term structure described by spot rates today is an input to the model. In fact such models could be described not as models per se, but essentially a description of an arbitrary process that governs changes in the yield curve, and projects a forward curve that results from the mean and volatility of the current short-term rate. An equilibrium term structure model is rather more a true model of the term structure process in an equilibrium model the current term structure is an output from the model. An equilibrium model employs a statistical approach, assuming that market prices are observed with some statistical error, so that the term structure must be estimated, rather than taken as given. [Pg.254]


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See also in sourсe #XX -- [ Pg.240 ]




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