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Main equation

As we have seen in previous chapters, it is possible to act on a material system mechanically (by expansion and compression. ..), thermally (by heating and cooling. .. ) and chemically (by addition or reaction of substances). All these actions are accompanied by changes of energy. These energy changes can be combined into a single equation, the so-called main equation. [Pg.249]

Introduction Homogeneous regions, in which pressure, temperamre, and composition are the same throughout, form the basic building blocks of the systems that matter dynamics deals with. A region of this type is called a phase (Sect. 1.5). When two parts of such a phase are combined, the quantities such as volume V, entropy S, amount of substance n etc., add up while pressure p, temperature T, the chemical potential // etc., remain the same. The first type of quantities are called extensive quantities and the second intensive quantities (Sect 1.6). Not every quantity fits into one of these categories. For instance, and y/S are neither one nor the other and there are others like them. [Pg.249]

Let us imagine a gas in a cylinder with a piston. The material system we observe is the gas and the concrete system we operate with is the gas-fiUed cylinder. Keeping the gas in the enclosure allows us to control the mechanical quantities p and y. We specify the force F upon the piston being pushed inside the cylinder, and a length I to quantify its position such as the distance between the piston and the bottom of the cylinder. We now imagine two identical gas-filled cylinders. How do the two quantities F and / behave when we merge the two systems into one This is not initially clear and depends upon how this step is carried out (Fig. 9.1). [Pg.250]

Similar problems appear in many other systems as well, such as in the galvanic cells which we will discuss in Chap. 23. In parallel and series connections, voltage U and transported charge Q behave like F and / in our example. The possibility of classifying quantities as either extensive or intensive is a distinctive feature of homogeneous systems and should not be thoughtlessly generalized. [Pg.250]

Inflow of entropy also leads to an increase in the content of energy (Sect. 3.11) of [Pg.250]


The main equation of the model describes the dependence of retention factor, k, from surfactant concentration, c and modifier concentration, c ... [Pg.81]

Every measured quantity or component in the main equations, Eqs. (12.30) and (12.31), influence the accuracy of the final flow rate. Usually a brief description of the estimation of the confidence limits is included in each standard. The principles more or less follow those presented earlier in Treatment of Measurement Uncertainties. There are also more comprehensive error estimation procedures available.These usually include, beyond the estimation procedure itself, some basics and worked examples. [Pg.1162]

APPENDIX A Derivation of the Main Equation of Debye-Hiickel Theory... [Pg.701]

APPENDIX A DERIVATION OF THE MAIN EQUATION OF DEBYE-HUCKEL THEORY... [Pg.702]

APPENDIX A DERIVATION OE THE MAIN EQUATION OE DEBYE-HUCKEL THEORY 703... [Pg.703]

This is Eq. (7.33), the main equation of the first version of Debye-Hiickel theory. [Pg.703]

The main equation, which allows understanding the physical sense of 0-0 frequency shifts in the spectra after inserting a molecule from gas phase into the solvent, is ... [Pg.210]

PARABOLIC MODEL OF BIMOLECULAR HOMOLYTIC REACTION 4.4.1 Main Equations of IPM... [Pg.187]

The distance re characterizes the displacement of the abstracted atom in the elementary step. The main equations of IPM are given in Chapter 4. [Pg.243]

The main equations used to extract thermochemical data from rate constants of reactions in solution were presented in section 3.2. Here, we illustrate the application of those equations with several examples quoted from the literature. First, however, recall that the rate constant for any elementary reaction in solution, defined in terms of concentrations, is related to the activation parameters through equations 15.1 or 15.2. [Pg.219]

Fluorescence is presented in this book from the point of view of a physical chemist, with emphasis on the understanding of physical and chemical concepts. Efforts have been made to make this book easily readable by researchers and students from any scientific community. For this purpose, the mathematical developments have been limited to what is strictly necessary for understanding the basic phenomena. Further developments can be found in accompanying boxes for aspects of major conceptual interest. The main equations are framed so that, in a first reading, the intermediate steps can be skipped. The aim of the boxes is also to show illustrations chosen from a variety of fields. Thanks to such a presentation, it is hoped that this book will favor the relationship between various scientific communities, in particular those that are relevant to physicochemical sciences and life sciences. [Pg.395]

The most common model for describing adsorption equilibrium in multi-component systems is the Ideal Adsorbed Solution (IAS) model, which was originally developed by Radke and Prausnitz [94]. This model relies on the assumption that the adsorbed phase forms an ideal solution and hence the name IAS model has been adopted. The following is a summary of the main equations and assumptions of this model (Eqs. 22-29). [Pg.180]

With phosphoric acid, the main equation becomes ... [Pg.112]

In addition to the general treatments of wavy flow, a number of theories concerning the stability of film flow have been published in these the flow conditions under which waves can appear are determined. The general method of dealing with the problem is to set up the main equations of flow (usually the Navier-Stokes equations or the simplified Nusselt equations), on which small perturbations are imposed, leading to an equation of the Orr-Sommerfeld type, which is then solved by various approximate means to determine the conditions for stability to exist. The various treatments are lengthy, and only the briefest summaiy of the results can be given here. [Pg.163]

As already mentioned in the Introduction, the exact solution of the main equation of quantum mechanics - the Schrodinger equation - lies beyond the potentialities of modem mathematics and computer technology. But a number of important inferences about the behaviour, structure and properties of a given quantum-mechanical many-particle system can be drawn without solving this equation, just by examining its symmetry properties. [Pg.109]

The design or simulation of FCC units involves numerically solving the above 21 equations and relations (7.25) to (7.45). The solution process will be discussed later. For the simulation of industrial units and the verification of this model for industrial data, the majority of these 21 equations are used to calculate various parameters in the 10 equations numbered (7.29) to (7.38). Specifically, equations (7.33) to (7.35) compute the concentration and temperature profiles in the bubble phase of the reactor and equation (7.38) computes the temperature profile in the regenerator. This leaves the main equations (7.29) to (7.32), (7.36), and (7.38) as six coupled equations in the six state variables xid, X2D, Yrd, d e, and Yqd-... [Pg.439]

The book is divided into two parts. Part One introduces the reader to solid oxide fuel cells, the related main thermodynamic principles, and the main equations to be used for modeling purposes. [Pg.406]

First consider the main equation that governs the heat transferred. [Pg.163]

The main equation for the d-electron GF in PAM coincides with the equation for the Hubbard model if the hopping matrix elements t, ) in the Hubbard model are replaced by the effective ones Athat are V2 and depend on frequency. By iteration of this equation with respect to Aij(u>) one can construct a perturbation theory near the atomic limit. A singular term in the expansions, describing the interaction of d-electrons with spin fluctuations, was found. This term leads to a resonance peak near the Fermi-level with a width of the order of the Kondo temperature. The dynamical spin susceptibility in the paramagnetic phase in the hydrodynamic limit was also calculated. [Pg.154]

In the previous section, the main equations used for building unstructured and non-segregated generic models were discussed. In principle, the description of an animal cell system can be based on any of these formulas, or combinations of them, as can be seen in some literature reviews (Tziampazis and Sambanis, 1994 Portner and Schafer, 1996 Sidoli et al., 2004). Nevertheless, the complexity of animal cell systems also demands alternative mathematical expressions for the full description of observed phenomena. [Pg.199]

This is the main equation of the model, describing the progress of the reforming and the oxidation process along the spatial coordinate, t,. [Pg.54]

Errors in the description of nonequilibrium processes in the linear nonequilibrium thermodynamics (Glansdorff et al., 1971 Kondepudi et al., 2000 Prigogine, 1967 Zubarev, 1998) are caused primarily by the assumptions (unnecessary at MEIS application) on the linearity of motion equations. One of the main equations of this thermodynamics has the form... [Pg.47]

Horowitz and Delannoy [157] have modified the TFT theory to take into account the presence of the traps and the trapped charges. The main equations used in their model are given below. [Pg.137]

The second term in Eq. (1.36) accounts for the non-isomorphic change of cell shape in the process of its transformation into a polyhedron. The value of this term does not exceed 2.8% of the main equation term and equals zero when volume fraction in close-packed spheres). [Pg.32]

Utilizing the smallness of the five-dimensional globular core and the smoothing properties of the integral operator g, we can rewrite the main equation (5.6) in the form of the linear second order integral equation (cf.38)) ... [Pg.88]

The main equation for calculation of Keff with the fission chamber count rate is determined by the formula ... [Pg.214]

Modelling usually includes several consecutive steps of calculations therefore, to make the method practical, the software simplification of the main equations has to be accepted with respect to the practical application. In many cases, we can reduce the simulation complications without impairing the reliability of the obtained results. [Pg.187]


See other pages where Main equation is mentioned: [Pg.161]    [Pg.707]    [Pg.7]    [Pg.176]    [Pg.245]    [Pg.8]    [Pg.23]    [Pg.66]    [Pg.106]    [Pg.81]    [Pg.449]    [Pg.161]    [Pg.187]    [Pg.382]    [Pg.319]    [Pg.54]   
See also in sourсe #XX -- [ Pg.250 ]




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