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Fundamental equations derivations

A fundamental equation derived by Gibbs is used to calculate the spreading pressure of films on solids where, unlike films on liquids, it cannot be experimentally determined. Guggenheim and Adam reduced Gibbs general adsorption equation to equation (7.3) for the special case of gas adsorption... [Pg.45]

This is the fundamental equation derived by JQrkwood and Riseman to treat both macromolecular friction and intrinsic viscosity. [Pg.60]

With the preceding introduction to the handling of surface excess quantities, we now proceed to the derivation of the third fundamental equation of surface chemistry (the Laplace and Kelvin equations, Eqs. II-7 and III-18, are the other two), known as the Gibbs equation. [Pg.73]

The analogy between equations derived from the fundamental residual- and excess-propeily relations is apparent. Whereas the fundamental lesidanl-pL-opeRy relation derives its usefulness from its direct relation to equations of state, the ci cc.s.s-property formulation is useful because V, and y are all experimentally accessible. Activity coefficients are found from vapor/liquid equilibrium data, and and values come from mixing experiments. [Pg.521]

These fundamental equations apply to many systems involving diserete entities aerosols, moleeules, and partieles, even people. A full review of their derivation of these equations is to be found in Randolph and Larson (1988), who have pioneered their applieation to industrial erystallizers in partieular. [Pg.55]

Equation derived from / SS ASHRAE Handbook of Fundamentals, Chapter 22, assiim-ing an air change every five (5) minutes. Refer to the ASHRAE Handbook, Chapter 22, for additional information on naturally ventilated buildings. [Pg.512]

In this section we show how the fundamental equations of hydrodynamics — namely, the continuity equation (equation 9.3), Euler s equation (equation 9.7) and the Navier-Stokes equation (equation 9.16) - can all be recovered from the Boltzman equation by exploiting the fact that in any microscopic collision there are dynamical quantities that are always conserved namely (for spinless particles), mass, momentum and energy. The derivations in this section follow mostly [huangk63]. [Pg.481]

These equations can be used to derive the four fundamental equations of Gibbs and then the 50,000,000 equations alluded to in Chapter 1 that relate p, T, V, U, S, H, A, and G. We should keep in mind that these equations apply to a reversible process involving pressure-volume work only. This limitation does not restrict their usefulness, however. Since all of the thermodynamic variables are state functions, calculation of AZ (Z is any of these variables) by a reversible path between two states gives the same value as would be obtained for all other paths between those states. When other forms of work are involved, additions can be made to the equations to account for the additional work. The... [Pg.105]

These are the fundamental equations for the design of thick cylinders and are often referred to as Lame s equations, as they were first derived by Lame and Clapeyron (1833). The constants A and B are determined from the boundary conditions for the particular loading condition. [Pg.874]

Now the equations derived from Kirchoff s first law are essentially material balances around each of (N — 1) vertices. As an alternative, balances could also be drawn up around groups of such vertices. Is there a special way of grouping the vertices, which will yield a particularly advantageous formulation Also, as we have noted, the selection of cycles is not unique, but the cycles must be independent. How can we generate an independent set of cycles Are some of these independent sets more fundamental than others If so, how many fundamental sets are there To answer these questions we must explore further the properties of a graph. [Pg.133]

Chapters 3 to 7 treat the aspects of chemical kinetics that are important to the education of a well-read chemical engineer. To stress further the chemical problems involved and to provide links to the real world, I have attempted where possible to use actual chemical reactions and kinetic parameters in the many illustrative examples and problems. However, to retain as much generality as possible, the presentations of basic concepts and the derivations of fundamental equations are couched in terms of the anonymous chemical species A, B, C, U, V, etc. Where it is appropriate, the specific chemical reactions used in the illustrations are reformulated in these terms to indicate the manner in which the generalized relations are employed. [Pg.598]

We reached this point from the discussion just prior to equation 44-64, and there we noted that a reader of the original column felt that equation 44-64 was being incorrectly used. Equation 44-64, of course, is a fundamental equation of elementary calculus and is itself correct. The problem pointed out was that the use of the derivative terms in equation 44-64 implicitly states that we are using the small-noise model, which, especially when changing the differentials to finite differences in equation 44-65, results in incorrect equations. [Pg.259]

Third-order susceptibilities of the PAV cast films were evaluated with the third-harmonic generation (THG) measurement [31,32]. The THG measurement was carried out at fundamental wavelength of 1064 nm and between 1500 nm and 2100 nm using difference-frequency generation combined with a Q-switched Nd YAG laser and a tunable dye laser. From the ratio of third-harmonic intensities I3m from the PAV films and a fused quartz plate ( 1 thick) as a standard, the value of x(3) was estimated according to the following equation derived by Kajzar et al. [33] ... [Pg.322]

Young 5941 derived a set of fundamental equations for gas-droplet multiphase flows in which small liquid droplets polydisperse... [Pg.343]

These are the fundamental equations of two-beam dynamical theory, which allow us to predict the wavefields and their intensities inside (and outside) the crystal. Of course, there are many consequential derivations and solutions, especially... [Pg.89]

Since it is relatively easy to transfer molecules from bulk liquid to the surface (e.g. shake or break up a droplet of water), the work done in this process can be measured and hence we can obtain the value of the surface energy of the liquid. This is, however, obviously not the case for solids (see later section). The diverse methods for measuring surface and interfacial energies of liquids generally depend on measuring either the pressure difference across a curved interface or the equilibrium (reversible) force required to extend the area of a surface, as above. The former method uses a fundamental equation for the pressure generated across any curved interface, namely the Laplace equation, which is derived in the following section. [Pg.15]

There are several ways to derive the fundamental equation for fractional melting. Here we choose an approach that can be easily understood. [Pg.23]

Equation (1.3) represents a very simple model, and that simplicity derives, presumably, from the small volume of chemical space over which it appears to hold. As it is hard to imagine deriving Eq. (1.3) from the fundamental equations of quantum mechanics, it might be more descriptive to refer to it as a relationship rather than a model . That is, we make some attempt to distinguish between correlation and causality. For the moment, we will not parse the terms too closely. [Pg.3]

Statistical mechanics is, obviously, a course unto itself in the standard chemistry/physics curriculum, and no attempt will be made here to introduce concepts in a formal and rigorous fashion. Instead, some prior exposure to the field is assumed, or at least to its thermodynamical consequences, and the fundamental equations describing the relationships between key thermodynamic variables are presented without derivation. From a computational-chemistry standpoint, many simplifying assumptions make most of the details fairly easy to follow, so readers who have had minimal experience in this area should not be adversely affected. [Pg.357]

The fundamental equations of transition-state theory may be derived in a number of different ways. Presented here is a somewhat less rigorous derivation that has the benefit of being pleasantly intuitive. Other derivations may be found in the sources Usted in the bibliography at the end of the chapter, or in references therein. [Pg.524]

As first shown by J. W. Gibbs, the analytical characterization of thermodynamic equilibrium states can be expressed completely in terms of such first and second derivatives of a certain fundamental equation (as described in Section 5.1). [Pg.6]

In this section, we wish to derive the Gibbs-Duhem equation, the fundamental relationship between the allowed variations dRt of the intensive properties of a homogeneous (singlephase) system. Paradoxically, this relationship (which underlies the entire theory of phase equilibria to be developed in Chapter 7) is discovered by considering the fundamental nature of extensive properties Xu as well as the intrinsic scaling property of the fundamental equation U = U(S, V, n, n2,. .., nc) that derives from the extensive nature of U and its Gibbs-space arguments. [Pg.201]

From the fundamental equation, we derive the equations of state for the intensive fields Rt as the successive partial derivatives... [Pg.204]

The second class of control variables comprises derivative strength-type ( intensive ) properties Rb such as temperature and pressure. Each Rt is related through the fundamental equation (8.72) to a conjugate extensity Xt by a derivative relationship ( equation of state ) of the form [cf. (3.32), (4.33)]... [Pg.306]


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See also in sourсe #XX -- [ Pg.80 , Pg.82 , Pg.90 , Pg.91 , Pg.92 ]




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