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Expanded Expansion

Tj = expander inlet temperature I p = expander expansion ratio Cp, k = gas constants determined by the gas equations... [Pg.223]

Provision for differential expansion Individual tubes free to expand expansion joint in shell floating head floating head floating head... [Pg.26]

The kinetic theory model can be used to explain how a substance changes from one state to another. If a solid is heated the particles vibrate faster as they gain energy. This makes them push their neighbouring particles further away from themselves. This causes an increase in the volume of the solid, and the solid expands. Expansion has taken place. [Pg.15]

Expansive phases Reacts and expands (expansion) pm (micro)... [Pg.275]

Expanded chains are found in dilute solution in good solvents. The effective interaction energy between two monomers is always repulsive here, and, as a consequence, chains become expanded. Expansion will come to an end at some finite value since it is associated with a decreasing conformational entropy. The reason for this decrease is easily seen by noting that the number of accessable rotational isomeric states decreases with increasing chain extension. The decrease produces a retracting force which balances, at equilibrium, the repulsive excluded volume forces. [Pg.43]

Even if the glazing is under compressive stress, crazing can occur in service. The reason is that glazes can absorb moisture and expand. Expansion brings about the tensile stress. The solutions for this problem are as follows ... [Pg.321]

Let us assume that stress gradient in axial direction is present but smooth. Then we can use a perturbation method and expand the solution of equation (30) in a series. The first term of this expansion will be a solution of the plane strain problem and potential N will be equal to zero. The next terms of the stress components will contain potential N also. [Pg.138]

It is worthwhile, albeit tedious, to work out the condition that must satisfied in order for equation (A1.1.117) to hold true. Expanding the trial fiinction according to equation (A1.1.113). assuming that the basis frmctions and expansion coefficients are real and making use of the teclmiqiie of implicit differentiation, one finds... [Pg.38]

Long-range forces are most conveniently expressed as a power series in Mr, the reciprocal of the intemiolecular distance. This series is called the multipole expansion. It is so connnon to use the multipole expansion that the electrostatic, mduction and dispersion energies are referred to as non-expanded if the expansion is not used. In early work it was noted that the multipole expansion did not converge in a conventional way and doubt was cast upon its use in the description of long-range electrostatic, induction and dispersion interactions. However, it is now established [8, 9, 10, H, 12 and 13] that the series is asymptotic in Poincare s sense. The interaction energy can be written as... [Pg.187]

The electrostatic potential generated by a molecule A at a distant point B can be expanded m inverse powers of the distance r between B and the centre of mass (CM) of A. This series is called the multipole expansion because the coefficients can be expressed in temis of the multipole moments of the molecule. With this expansion in hand, it is... [Pg.189]

The perturbation theory described in section Al.5.2,1 fails completely at short range. One reason for the failure is that the multipole expansion breaks down, but this is not a fiindamental limitation because it is feasible to construct a non-expanded , long-range, perturbation theory which does not use the multipole expansion [6], A more profound reason for the failure is that the polarization approximation of zero overlap is no longer valid at short range. [Pg.195]

The details of the second-order energy depend on the fonn of exchange perturbation tiieory used. Most known results are numerical. However, there are some connnon features that can be described qualitatively. The short-range mduction and dispersion energies appear in a non-expanded fonn and the differences between these and their multipole expansion counterparts are called penetration tenns. [Pg.198]

The interaction energy can be written as an expansion employing Wigner rotation matrices and spherical hamionics of the angles [28, 130], As a simple example, the interaction between an atom and a diatomic molecule can be expanded hr Legendre polynomials as... [Pg.208]

Assume that the free energy can be expanded in powers of the magnetization m which is the order parameter. At zero field, only even powers of m appear in the expansion, due to the up-down symmetry of the system, and... [Pg.536]

Here the coefficients G2, G, and so on, are frinctions ofp and T, presumably expandable in Taylor series around p p and T- T. However, it is frequently overlooked that the derivation is accompanied by the connnent that since. . . the second-order transition point must be some singular point of tlie themiodynamic potential, there is every reason to suppose that such an expansion camiot be carried out up to temis of arbitrary order , but that tliere are grounds to suppose that its singularity is of higher order than that of the temis of the expansion used . The theory developed below was based on this assumption. [Pg.643]

The density is computed as p(r) = 2. n i ). (/ )p. Often, p(r) is expanded in an AO basis, which need not be the same as the basis used for the and the expansion coefficients of p are computed in tenns of those of the It is also connnon to use an AO basis to expand p (r) which, together with p, is needed to evaluate the exchange-correlation fiinctionaTs contribution toCg. [Pg.2183]

The conceptually simplest approach to solve for the -matrix elements is to require the wavefimction to have the fonn of equation (B3.4.4). supplemented by a bound function which vanishes in the asymptote [32, 33, 34 and 35] This approach is analogous to the fiill configuration-mteraction (Cl) expansion in electronic structure calculations, except that now one is expanding the nuclear wavefimction. While successfiti for intennediate size problems, the resulting matrices are not very sparse because of the use of multiple coordinate systems, so that this type of method is prohibitively expensive for diatom-diatom reactions at high energies. [Pg.2295]

Each logarithm in the last temi can now be expanded and the (—n)th Fourier coefficient arising fi om each logarithm is — jn) zk-Y- To this must be added the n = 0 Fourier coefficient coming from the first, f-independent term and that arising from the expansion of second term as a periodic function, namely. [Pg.121]

We shall expand the polynomial of z. But recalling that only terms of the even power of z do not vanish, we can write the expansion in the following form ... [Pg.424]

The basic idea of NMA is to expand the potential energy function U(x) in a Taylor series expansion around a point Xq where the gradient of the potential vanishes ([Case 1996]). If third and higher-order derivatives are ignored, the dynamics of the system can be described in terms of the normal mode directions and frequencies Qj and Ui which satisfy ... [Pg.72]

Series expansion Smith and van Gunsteren [4] investigated the first approach expanding the free energy as a function of the coupling parameter A into a T ylor series around a given reference state, A = 0,... [Pg.151]

HyperChem uses single detenu in am rather than spin-adapted wave fn n ction s to form a basis set for th e wave Fin ciion sin a con -figuration interaction expansion. That is, HyperChem expands a Cl wave function, m a linear combination of single Slater deterniinants P,... [Pg.235]


See other pages where Expanded Expansion is mentioned: [Pg.338]    [Pg.93]    [Pg.4]    [Pg.188]    [Pg.315]    [Pg.338]    [Pg.93]    [Pg.4]    [Pg.188]    [Pg.315]    [Pg.218]    [Pg.35]    [Pg.16]    [Pg.503]    [Pg.508]    [Pg.686]    [Pg.983]    [Pg.985]    [Pg.1125]    [Pg.1192]    [Pg.1244]    [Pg.2208]    [Pg.2211]    [Pg.2439]    [Pg.188]    [Pg.213]    [Pg.215]    [Pg.442]    [Pg.207]    [Pg.443]   
See also in sourсe #XX -- [ Pg.3 , Pg.18 , Pg.23 , Pg.33 , Pg.36 , Pg.53 , Pg.57 , Pg.68 , Pg.71 , Pg.104 , Pg.167 , Pg.188 ]




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