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Finding complex solutions

The previous discussion focused upon methods for finding solutions to f(x) = 0, where both X and f(x) are real. While this is generally the case in engineering and scientific [Pg.70]


Time complexity How long does it take to find the solution ... [Pg.292]

Solulink pairs "find" each other in complex solutions and conjugate... [Pg.673]

Chemical engineers, however, have to find practical ways for dealing with turbulent flows in flow devices of complex geometry. It is their job to exploit practical tools and find practical solutions, as spatial variations in turbulence properties usually are highly relevant to the operations carried out in their process equipment. Very often, the effects of turbulent fluctuations and their spatial variations on these operations are even crucial. The classical toolbox of chemical engineers falls short in dealing with these fluctuations and its effects. Computational Fluid Dynamics (CFD) techniques offer a promising alternative approach. [Pg.155]

Hilvert s group used the same hapten [26] with a different spacer to generate an antibody catalyst which has very different thermodynamic parameters. It has a high entropy of activation but an enthalpy lower than that of the wild-type enzyme (Table 1, Antibody 1F7, Appendix entry 13.2a) (Hilvert et al., 1988 Hilvert and Nared, 1988). Wilson has determined an X-ray crystal structure for the Fab fragment of this antibody in a binary complex with its TSA (Haynes et al., 1994) which shows that amino acid residues in the active site of the antibody catalyst faithfully complement the components of the conformationally ordered transition state analogue (Fig. 11) while a trapped water molecule is probably responsible for the adverse entropy of activation. Thus it appears that antibodies have emulated enzymes in finding contrasting solutions to the same catalytic problem. [Pg.270]

The second class of theories can be characterized as attempts to find approximate solutions to the Schrodinger equation of the molecular complex as a whole. Two approaches became important in numerical calculations perturbation theory (PT) and molecular orbital (MO) methods. [Pg.14]

The goodness of fit for this simple treatment can only be evaluated by comparison with the more exact but much more complex solutions. From such a comparison we find that the maximum error in estimate of D/wL is given by... [Pg.299]

Chromium(III) complexes of Schiff bases derived from pyridoxal and glycylglycine have bee prepared in solution in attempts to find complexes that show good intestinal absorption1125 (se also Section 35.4.8.3). [Pg.896]

Develop a method that finds the solution of the mathematical model equations. The method may be analytical or numerical. Its complexity needs to be understood if we want to monitor a system continuously. Whether a specific model can be solved analytically or numerically and how, depends to a large degree upon the complexity of the system and on whether the model is linear or nonlinear. [Pg.59]

Algorithmic and computational solutions for model (or design) equations, combined with chemical/biological modeling, are the main subjects of this book. We shall learn that the complexities for generally nonlinear chemical/biological systems force us to use mainly numerical techniques, rather than being able to find analytical solutions. [Pg.59]

Transform methods are used to solve two-variable linear differential equations essentially by means of the transformation of a partial differential equation into a total differential equation of one independent variable (in general, the number of variables is reduced by one) [1], The major inconvenience of these methods to find analytical solutions is that the inverse transformation is frequently very difficult or cannot be done at all even for not too complex electrochemical processes. In these cases, the solutions have an integral non-explicit form, from which it is not possible to deduce limit behaviors and the influence of the different variables cannot be inferred for a glance. In Electrochemistry, this method has been extensively used to solve the diffusion equation, which is a two-variable partial differential equation. [Pg.591]

As repeatedly mentioned by many experts, reaching a stable balance between the economic and social processes in any country and in the world as a whole is a complicated problem, the solution of which will call for a complex approach to study the dynamics of the NSS. The authors of the collection of papers edited by Spoor (2004) tried to find a solution to this problem. Analyzing the internal mechanisms of the interaction between present global processes such as globalization, poverty, and conflict, the authors posed and tried to answer the following questions ... [Pg.119]

When we have found a solution for the Laplace transformed function, then we need to make an inverse transformation to find the solution in terms of time and coordinates. There are elegant techniques for doing this based on the theory of complex functions, but often these are not necessary since there exist extensive tables in mathematical handbooks of functions and their Laplace transformed functions. Only in cases where the relevant functions have not been tabulated will it be necessary to carry out the inverse transformation using these techniques. [Pg.232]

Figures 17, 18, and 19 show the different catalytic cycles derived from the foregoing approach. The chain-carrying species of the cycles in Figs. 17 and 18 is an alkyl radical, whereas in the cycles of Fig. 19 it is a Ni(I) or an allylNi(I) complex. We may note that, for this example where both paramagnetic and diamagnetic intermediates were considered, TAMREAC did not find more solutions than Hegedus and Thompson did (127b). Figures 17, 18, and 19 show the different catalytic cycles derived from the foregoing approach. The chain-carrying species of the cycles in Figs. 17 and 18 is an alkyl radical, whereas in the cycles of Fig. 19 it is a Ni(I) or an allylNi(I) complex. We may note that, for this example where both paramagnetic and diamagnetic intermediates were considered, TAMREAC did not find more solutions than Hegedus and Thompson did (127b).
Using these methods to describe an aqueous electrolyte system with its associated chemical equilibria involves a unique set of highly nonlinear algebraic equations for each set of interest, even if not incorporated within the framework of a complex fractionation program. To overcome this difficulty, Zemaitis and Rafal (8) developed an automatic system, ECES, for finding accurate solutions to the equilibria of electrolyte systems which combines a unified and thermodynamically consistent treatment of electrolyte solution data and theory with computer software capable of automatic program generation from simple user input. [Pg.305]

In Example 10.1 the case where the aerosol concentration does not change with time was considered. In many practical situations, however, the aerosol concentration does change with time, possibly as a result of diffusion and subsequent loss of particles to a wall or other surface. In this event, Fick s second law, Eq. 9.2, must be used. Solution of this equation is possible in many cases, depending on the initial and boundary conditions chosen, although the solutions generally take on very complex forms and the actual mechanics involved to find these solutions can be quite tedious. Fortunately, there are several excellent books available which contain large numbers of solutions to the transient diffusion equation (Barrer, 1941 Jost, 1952). Thus, in most cases it is possible to fit initial and boundary conditions of an aerosol problem to one of the published solutions. Several commonly occurring examples follow. [Pg.86]

When charge-transfer bonds are obscured by those of the original donors and acceptors, one may find of value a difference method [1] (e.g., Forster s tandem method [70]). Four cuvets of equal path length are used, two containing the charge-transfer complex solutions in series in the indicator beam of a double-beam spectrophotometer, and two cuvets, one with the unreacted donor and the other with unreacted acceptor solution, also in series in the reference beam. A difference spectrum is thus obtained which, however, needs special care in its interpretation. [Pg.702]


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