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The general case

The sample solution must be neutral when it is applied to the first column, to ensure that all amphoterics are in the zwitterionic form. [Pg.100]

It must be understood that this scheme has not been validated in its entirety. It is, however, based on component parts that have either been completely validated or are at least supported by some experimental evidence. Matters not fully validated are the behaviour of SW amphoterics and the sorption of quaternary cationics on weakly acidic cation exchanger sodium salts. These should be confirmed by experiment before complete faith is placed in the scheme. [Pg.101]

Column 1 weakly basic anion exchanger hydrochloride. Retains anionics (including phosphate mono- and di-esters ). Elute with ammonia to deprotonate and therefore deionise the resin. [Pg.101]

Column 2 strongly basic anion exchanger hydroxide. Retains carboxy-lates and WW and SW amphoterics. Elute with hydrochloric acid. Car boxy lates and amphoterics are eluted rapidly. Response of phosphate esters is uncertain, but if they were not retained by column 1 they would be retained by column 2 and also eluted rapidly. Quaternary salts are converted to the hydroxide, weakly basic cationics (amines, amine oxides) to the free base and betaines to the zwitterionic form. All of these pass through. [Pg.101]

Column 3 Weakly acidic cation exchanger, sodium salt. Retains quaternary cationics. Weak bases and betaines pass through. Elute with hydrochloric acid, to protonate and therefore deionise the resin. Column 4 Strongly acidic cation exchanger, free acid. Retains weak bases and betaines. Effluent contains nonionics, sulphobetaines (SS amphoterics) and phosphate triesters. Elute with ammonia, to deprotonate and deionise weak bases and to convert the betaine to the zwitterionic form. [Pg.101]

The general case of a tube of arbitrary cross-section, flow profile and variation of diffusion coefficient, for which the equations were set up in 1, may be considered in a similar way. Again, m0 must be a constant, which may be taken as unity, and for c0 we have the equations [Pg.116]

Under very general conditions on T and I there will exist a positive increasing sequence of eigenvalues A and a complete set of ortho-normal eigenfunctions vn satisfying the equation [Pg.116]

As before, the density of solute in any streamline rapidly becomes uniform across the tube, the relaxation time being of the order of Af1, where A, is the smallest of the eigenvalues. [Pg.116]

Inserting this value of Co in equation (12) with p = 1, it is again evident that the centre of gravity ultimately moves with the mean speed of the stream. Its final position relative to a moving origin originally at the centre of gravity is [Pg.116]

Apart from mi. and terms which vanish as r — Ci will contain a constant function of rj and f whose mean value is zero. This function arises from the constant term 1 in Co when this is inserted in equation (9) with p = 1 and so must satisfy the equations [Pg.117]

For polypeptides with irregular sequences, as is the usual case for enzymes and other water-soluble globular proteins, the conformational situation ranges from totally random to a mixed situation with regular stretches intermingled with random (irregular) lengths of the backbone. [Pg.29]

Fasman, G. D. (1989) Prediction of Protein Structures and the Principles of Protein Conformation, Plenum, New York. [Pg.31]


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]

Many authors have shown that residual stresses in glass articles can be formally considered as the thermal stresses due to a certain fictitious temperature field. In the general case... [Pg.135]

The general case has been solved by Bashforth and Adams [14], using an iterative method, and extended by Sugden [15], Lane [16], and Paddy [17]. See also Refs. 11 and 12. In the case of a figure of revolution, the two radii of curvature must be equal at the apex (i.e., at the bottom of the meniscus in the case of capillary rise). If this radius of curvature is denoted by b, and the elevation of a general point on the surface is denoted by z, where z = y - h, then Eq. II-7 can be written... [Pg.14]

The equations are transcendental for the general case, and their solution has been discussed in several contexts [32-35]. One important issue is the treatment of the boundary condition at the surface as d is changed. Traditionally, the constant surface potential condition is used where po is constant however, it is equally plausible that ag is constant due to the behavior of charged sites on the surface. [Pg.181]

Equation XVI-21 provides for the general case of a molecule having n independent ways of rotation and a moment of inertia 7 that, for an asymmetric molecule, is the (geometric) mean of the principal moments. The quantity a is the symmetry number, or the number of indistinguishable positions into which the molecule can be turned by rotations. The rotational energy and entropy are [66,67]... [Pg.583]

For the interaction between a nonlinear molecule and an atom, one can place the coordinate system at the centre of mass of the molecule so that the PES is a fiinction of tlie three spherical polar coordinates needed to specify the location of the atom. If the molecule is linear, V does not depend on <() and the PES is a fiinction of only two variables. In the general case of two nonlinear molecules, the interaction energy depends on the distance between the centres of mass, and five of the six Euler angles needed to specify the relative orientation of the molecular axes with respect to the global or space-fixed coordinate axes. [Pg.186]

One concludes, therefore, that equation (A2.1.13) is integrable and there exists an mtegrating factor X. For the general case = X dij) it can be shown [I, 2] that... [Pg.335]

In the general case, (A3.2.23) caimot hold because it leads to (A3.2.24) which requires GE = (GE ) which is m general not true. Indeed, the simple example of the Brownian motion of a hannonic oscillator suffices to make the point [7,14,18]. In this case the equations of motion are [3, 7]... [Pg.699]

Only in the high-energy limit does classical statistical mechanics give accurate values for the sum and density of states tenns in equation (A3.12.15) [3,14]. Thus, to detennine an accurate RRKM lc(E) for the general case, quantum statistical mechanics must be used. Since it is difficult to make anliannonic corrections, both the molecule and transition state are often assumed to be a collection of hannonic oscillators for calculating the... [Pg.1018]

A fiill solution of tlie nonlinear radiation follows from the Maxwell equations. The general case of radiation from a second-order nonlinear material of finite thickness was solved by Bloembergen and Pershan in 1962 [40]. That problem reduces to the present one if we let the interfacial thickness approach zero. Other equivalent solutions involved tlie application of the boundary conditions for a polarization sheet [14] or the... [Pg.1277]

Given the interest and importance of chiral molecules, there has been considerable activity in investigating die corresponding chiral surfaces [, and 70]. From the point of view of perfomiing surface and interface spectroscopy with nonlinear optics, we must first examhie the nonlinear response of tlie bulk liquid. Clearly, a chiral liquid lacks inversion synnnetry. As such, it may be expected to have a strong (dipole-allowed) second-order nonlinear response. This is indeed true in the general case of SFG [71]. For SHG, however, the pemiutation synnnetry for the last two indices of the nonlinear susceptibility tensor combined with the... [Pg.1286]

Wlien describing the interactions between two charged flat plates in an electrolyte solution, equation (C2.6.6) cannot be solved analytically, so in the general case a numerical solution will have to be used. Several equations are available, however, to describe the behaviour in a number of limiting cases (see [41] for a detailed discussion). Here we present two limiting cases for the interactions between two charged spheres, surrounded by their counterions and added electrolyte, which will be referred to in further sections. This pair interaction is always repulsive in the theory discussed here. [Pg.2678]

Now, consider the general case of a V2 multiply excited degenerate vibrational level where V2 > 2, which is dealt with by solving the Schrddinger equation for the isotropic 2D harmonic oscillator with the Hamiltonian assuming the fonn [95]... [Pg.622]

To treat the general case, we assume A and x to be of tbe following form ... [Pg.650]

In Section V.A, we present a few analytical examples showing that the reshictions on the x-matrix elements are indeed quantization conditions that go back to the early days of quantum theory. Section V.B will be devoted to the general case. [Pg.652]

In our introductory remarks, we said that this section would be devoted to model systems. Nevertheless it is important to emphasize that although this case is treated within a group of model systems this model stands for the general case of a two-state sub-Hilbert space. Moreover, this is the only case for which we can show, analytically, for a nonmodel system, that the restrictions on the D matrix indeed lead to a quantization of the relevant non-adiabatic coupling term. [Pg.654]

Our next task is to derive all possible K values for a given Nj. First, we refer to a few special cases It was shown before that in case of Ay = 1 the D matrix contains two (—1) terms in its diagonal in case the contoui surrounds the conical intersection and no (—1) terms when the contour does not surround the conical intersection. Thus the allowed values of K aie either 2 or 0. The value A = 1 is not allowed. A similar inspection of the case Nj = 2 reveals that K, as before, is equal either to 2 or to 0 (see Section V.B). Thus the values K = or 3 are not allowed. From here, we continue to the general case and prove the following statement ... [Pg.666]

One may attempt to correct an integrator by an energy projection, i.e., in the general case of integrating some Hamiltonian H q,p), after a specified number I of steps, we would solve the equation... [Pg.357]

The general case of two masses bound by two lateral springs k and L2, and coupled by a coupling spring, in Fig. 5-2b, has... [Pg.138]

We cannot solve the Schroedinger equation in closed fomi for most systems. We have exact solutions for the energy E and the wave function (1/ for only a few of the simplest systems. In the general case, we must accept approximate solutions. The picture is not bleak, however, because approximate solutions are getting systematically better under the impact of contemporary advances in computer hardware and software. We may anticipate an exciting future in this fast-paced field. [Pg.169]

We have assumed that the order of the subscripts on the atomic orbitals p is immaterial in writing a, p, and S. In the general case, these assumptions are not self-evident, especially for p. The interested reader should consult a good quantum mechanics text (e.g., Hanna, 1981 McQuarrie, 1983 Atkins and Eriedman, 1997) for their justification or critique. [Pg.183]

The Slater-type orbitals are a family of functions that give us an economical way of approximating various atomic orbitals (which, for atoms other than hydrogen, we don t know anyway) in a single relatively simple form. For the general case, STOs are written... [Pg.243]

In the general case of an electronic Hamiltonian for atoms or molecules under the Bom-Oppenheimer approximation,... [Pg.275]

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]


See other pages where The general case is mentioned: [Pg.367]    [Pg.132]    [Pg.184]    [Pg.737]    [Pg.790]    [Pg.470]    [Pg.171]    [Pg.698]    [Pg.2333]    [Pg.122]    [Pg.332]    [Pg.339]    [Pg.340]    [Pg.430]    [Pg.634]    [Pg.658]    [Pg.661]    [Pg.355]    [Pg.58]    [Pg.141]    [Pg.253]    [Pg.310]    [Pg.181]    [Pg.255]    [Pg.272]    [Pg.11]   


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