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Screening numerical solution

The flow becomes highly complex in a spiral-wound module containing a feed-side spacer screen. Numerical solutions of the governing equations incorporating most of these complexities have been/are being implemented (Wiley and Fletcher, 2003) using computational fluid dynamics models (see Schwinge et al. (2003) for the complex flow patterns in a spacer-filled channel). [Pg.567]

The solutions to this approximation are obtained numerically. Fast Fourier transfonn methods and a refomuilation of the FINC (and other integral equation approximations) in tenns of the screened Coulomb potential by Allnatt [M are especially useful in the numerical solution. Figure A2.3.12 compares the osmotic coefficient of a 1-1 RPM electrolyte at 25°C with each of the available Monte Carlo calculations of Card and Valleau [ ]. [Pg.495]

Values of GENp calculated from the GB approximation compare well to values obtained from numerical solution of the Poisson equation for similar collections of point charges [83,237,238], A very promising extension of the GB methods is provided by a new scaled pairwise approximation to the dielectric screening integrals [215],... [Pg.28]

A successor to PESTANS has recently been developed which allows the user to vary transformation rate and with depth l.e.. It can describe nonhomogeneous (layered) systems (39,111). This successor actually consists of two models - one for transient water flow and one for solute transport. Consequently, much more Input data and CPU time are required to run this two-dimensional (vertical section), numerical solution. The model assumes Langmuir or Freundllch sorption and first-order kinetics referenced to liquid and/or solid phases, and has been evaluated with data from an aldlcarb-contamlnated site In Long Island. Additional verification Is In progress. Because of Its complexity, It would be more appropriate to use this model In a hl er level, rather than a screening level, of hazard assessment. [Pg.309]

If co-crystallization is indicated by properties of the protein or the fragment library, then prepare a solution of the protein with suitable concentration of fragment(s), (suggested 100 mM). Screen this solution around known crystallization conditions for the protein. If no crystals are observed a full screen using numerous conditions may be indicated. [Pg.248]

Whereas the coupled equations of the polarization model can be solved analytically in the linear approximation (which is valid only for small potentials), in the general case one must rely on numerical solutions [7.5]. The polarization model can explain the restabilization of protein-stabilized polymer latexes, for which the increase in the repulsive force generated by the surface dipoles more than compensates for the decrease in repulsion caused by the decrease in the surface charge and the increase in the screening of the electrostatic field by the increasing ionic strength [7.5]. [Pg.512]

Below we consider the problem of screening of a finite-size charge Zina plasma background for the range % 1 — 50 in two ways. The first one is the accurate numerical solution of the above PB equations. The other one is the method of MC computer simulations providing a microscopic description of screening. [Pg.295]

The difference between and the full renormalized potential is a well-behaved function that is evaluated numerically. The interest in the renormalization procedure is now mainly a theoretical one as formal results regarding screening and other thermodynamic parameters can be obtained this way. Results applicable to both pure one-component fluids or mixtures can be obtained. The numerical solution of integral equations, such as the SSOZ and CSL equations, for sites with charge interactions should no longer use the renormalization method but rather the method we are about to describe. [Pg.508]

As Figure 19 illustrates, Mathcad provides perhaps the pedagogically most powerful interface for numerical solutions. Text, parameters, the integration algorithm, and a graphic display of the solution can be present on the screen simultaneously in one live document. In this application, once the pa-... [Pg.207]

With eqns (1.52) and (1.53) there are four equations for the four unknown coverages 0q2> o, dco, and 0 and the system of nonlinear algebraic equations may be solved numerically. With currently available CPU speeds numerical solutions to microkinetic models for catalyst screening studies are generally preferred because they avoid the need to make any additional assumptions regarding the mechanism. [Pg.38]

Figure 11.15. Plots of typical numerical solutions for the screened Coulomb Schrodinger wave equation eigenvalue problem. Figure 11.15. Plots of typical numerical solutions for the screened Coulomb Schrodinger wave equation eigenvalue problem.
Exact solutions to the electronic Schrodinger equation are not possible for many-electron atoms, but atomic HF calculations have been done both numerically and within the LCAO model. In approximate work, and for molecular applications, it is desirable to use basis functions that are simple in form. A polyelectron atom is quite different from a one-electron atom because of the phenomenon of shielding", for a particular electron, the other electrons partially screen the effect of the positively charged nucleus. Both Zener (1930) and Slater (1930) used very simple hydrogen-like orbitals of the form... [Pg.157]


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