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Equilibria general case

Using the equilibrium equations of the elasticity theory enables one to determine the stress tensor component (Tjj normal to the plane of translumination. The other stress components can be determined using additional measurements or additional information. We assume that there exists a temperature field T, the so-called fictitious temperature, which causes a stress field, equal to the residual stress pattern. In this paper we formulate the boundary-value problem for determining all components of the residual stresses from the results of the translumination of the specimen in a system of parallel planes. Theory of the fictitious temperature has been successfully used in the case of plane strain [2]. The aim of this paper is to show how this method can be applied in the general case. [Pg.132]

The equilibrium shape of a liquid lens floating on a liquid surface was considered by Langmuir [59], Miller [60], and Donahue and Bartell [61]. More general cases were treated by Princen and Mason [62] and the thermodynamics of a liquid lens has been treated by Rowlinson [63]. The profile of an oil lens floating on water is shown in Fig. IV-4. The three interfacial tensions may be represented by arrows forming a Newman triangle ... [Pg.112]

While the Lorentz model only allows for a restoring force that is linear in the displacement of an electron from its equilibrium position, the anliannonic oscillator model includes the more general case of a force that varies in a nonlinear fashion with displacement. This is relevant when tire displacement of the electron becomes significant under strong drivmg fields, the regime of nonlinear optics. Treating this problem in one dimension, we may write an appropriate classical equation of motion for the displacement, v, of the electron from equilibrium as... [Pg.1266]

System in which the solid phases consist of the pure components and the components are completely miscible in the liquid phase. We may now conveniently consider the general case of a system in which the two components A and B are completely miscible in the liquid state and the solid phases consist of the pure components. The equilibrium diagram is shown in Fig. 1,12, 1. Here the points A and B are the melting points of the pure components A and B respectively. If the freezing points of a series of liquid mixtures, varying in composition from pure A to pure B, are determined, the two curves represented by AC and BC will be obtained. The curve AC expresses the compositions of solutions which are in equilibrium, at different temperatures, with the solid component A, and, likewise, the curve BC denotes the compositions... [Pg.24]

The general case of two compounds forming a continuous series of solid solutions may now be considered. The components are completely miscible in the sohd state and also in the hquid state. Three different types of curves are known. The most important is that in which the freezing points (or melting points) of all mixtures lie between the freezing points (or melting points) of the pure components. The equilibrium diagram is shown in Fig. 7, 76, 1. The hquidus curve portrays the composition of the hquid phase in equihbrium with sohd, the composition of... [Pg.32]

When R = H, in all the known examples, the 3-substituted tautomer (129a) predominates, with the possible exception of 3(5)-methylpyrazole (R = Me, R = H) in which the 5-methyl tautomer slightly predominates in HMPT solution at -17 °C (54%) (77JOC659) (Section 4.04.1.3.4). For the general case when R = or a dependence of the form logjRTT = <2 Za.s cTi + b Xa.s (Tr, with a>0,b <0 and a> b, has been proposed for solutions in dipolar aprotic solvents (790MR( 12)587). The equation predicts that the 5-trimethylsilyl tautomer is more stable than the 3-trimethylsilylpyrazole, since experimental work has to be done to understand the influence of the substituents on the equilibrium constant which is solvent dependent (78T2259). There is no problem with indazole since the IH tautomer is always the more stable (83H(20)1713). [Pg.211]

The value of equilibrium moisture content, for many materials, depends on the direction in which equilibrium is approached. A different value is reached when a wet material loses moisture by desorption, as in drying, from that obtained when a diy material gains it by adsorption. For diying calculations the desorption values are preferred. In the general case, the equilibrum moisture content reached by losing moisture is higher than tnat reached by adsorbing it. [Pg.1182]

The exact position of the aldol equilibrium depends both on reaction conditions and on substrate structure. The equilibrium generally favors condensation product in the case of aldehydes with no a substituent (RCH2CHO) but favors reactant for disubstituted aldehydes (R2CHCHO) and for most ketones. Steric Factors are probably responsible for these trends, since increased substitution near the reaction site increases steric congestion in the aldol product. [Pg.879]

More will be said about jump experiments in Chapter 11, which deals with fast reaction techniques. Very fast equilibration reactions are especially amenable to this method. As developed there, a first-order equation describes the approach to equilibrium irrespective of the actual rate law. The most general case is represented by an elementary reaction of the form... [Pg.55]

First, it proves handy to rederive the ripplon spectrum from Eq. (34) in the less general case = 0 (but nonzero pressure ). As argued in Section IV, the droplet wall is at equilibrium pressure... [Pg.195]

The solution to the general decay equations is often given in textbooks (e.g., Faure 1986). However, this solution is given for initial abundances of the daughter nuclides that are equal to zero. In the most general cases, the initial abundances of the daughter nuclides are not equal to zero. For example, in many geological examples, we make the assumptions that the decay chain is in secular equilibrium. The solutions of these equations can also be used to solve simple box models of U-series nuclides where first order kinetics are assumed. [Pg.22]

In the general case the value of K appearing in the driving force term is the product of the equilibrium constant for the surface reaction Kr and the product of the adsorption equilibrium constants for the reactants divided by the product of the adsorption equilibrium constants for the reaction products. [Pg.186]

Two general cases are considered (1) adsorption under conditions of constant or nearly constant external solution concentration (equivalent to infinite fluid volume) and (2) adsorption in a batch with finite volume. In the latter case, the fluid concentration varies from c°t to c7 when equilibrium is eventually attained. A = (c° - c /c = Ms(h7 — h0i)/(Vfc0i) is a partition ratio that represents the fraction of adsorbate that is ultimately adsorbed. It determines which general case should be considered in the analysis of experimental systems. Generally, when A90 > 0.1, solutions for the second case are required. [Pg.27]

When the drug entity is capable of forming complexes that have higher stoichiometric ratios than 1 1, the construction of equilibrium constant expressions becomes more difficult. For the general case of m.n stoichiometry, as defined by... [Pg.342]

In contrast with the equilibrium case, this equation still depends upon the charges of a and ft in a complicated manner. Although methods exist to treat the general case,8 we shall limit ourselves here to the case of a binary electrolyte, composed of species a and (a / ). The electroneutrality condition thus reads ... [Pg.222]

The method just described can only be applied in the simplest cases, where a single reaction is present. The equivalent of equation 11.20 for the general case of i equilibrium reactions inside the calorimetric vessel is... [Pg.164]

The definition of equilibrium constants for such general cases is most conveniently done via the so-called formation constants fixyz, which are defined in the following way ... [Pg.43]

Here we 11 consider a more general case assuming tne possibility of the cross-link formation between any two sites of the molecule raeeroaching one to another to some critical distance /we ll call such pairs "contacts"/ and assuming that the rate constant of the elementary act does not depend on the chain conformation as a whole and the nearest environment. Besides we ll assume that the reaction is a kinetically-controlled one, i.e. the system, reaches the state of the conformational equilibrium, between two consequent cross-links formations but the elementary act is irreversible and so fast that the chain conforma.tion remains constant during it Fs-sl. [Pg.26]

We can now distinguish three general cases, depending on whether the first decaying species has a longer, a much longer, or a shorter half-hfe than that of the daughter nuclide. These three cases are transient equilibrium, secular equilibrium, and nonequilibrium. [Pg.724]

In the general case of a metal/metal-ion electrode, a metal M is in an equilibrium with... [Pg.59]

Figure 9, Schematic showing energy correlations under conditions of illumination for the cell of Figure 8. Both electrodes are assumed to be illuminated and the general case of unequal band gaps is shown. The stored energy for oxidation is equal to EF(Oi/H20) — nE fn, surface) while that for reduction is EF(Hgo/H2> — pEf (p, surface), Ef denotes the Fermi level as it was at equilibrium in the dark in Figure 8, while Ef and Ef are the Fermi levels in the two metals when the semiconductors are both illuminated. Other symbols as in Figures 7 and 8 (13). Figure 9, Schematic showing energy correlations under conditions of illumination for the cell of Figure 8. Both electrodes are assumed to be illuminated and the general case of unequal band gaps is shown. The stored energy for oxidation is equal to EF(Oi/H20) — nE fn, surface) while that for reduction is EF(Hgo/H2> — pEf (p, surface), Ef denotes the Fermi level as it was at equilibrium in the dark in Figure 8, while Ef and Ef are the Fermi levels in the two metals when the semiconductors are both illuminated. Other symbols as in Figures 7 and 8 (13).
Let us extend this analysis to the general case of C independent, nonreacting components, so that we might arrive at a very useful, general conclusion. Instead of one component, we now have C and instead of two phases (liquid and solid), we now have an arbitrary number, 0. The conditions of equilibrium are now analogous to Eqs. (2.14)-(2.16) ... [Pg.141]

Not shown explicitly in the previous equation are the number Ans of solvent molecules released or consumed in the equilibrium, and in the general case, this can only be roughly estimated, if at all. In some cases many of the solvating molecules are... [Pg.80]

This is the concentration in equilibrium with the bulk gas concentration CG. It is important to note that in the general case,... [Pg.72]


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See also in sourсe #XX -- [ Pg.43 ]




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