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Mathematical concepts complex numbers

Before we go into the mathematical framework behind wave mechanics, we will review one more mathematical concept normally seen in high school imaginary and complex numbers. As discussed in Section 1.2, for a general quadratic equation ax2 + bx+c =... [Pg.128]

So far we have been concerned largely with the concept of the complex number, but we can see from our discussion of Euler s formula that the general form of a complex number actually represents a complex mathematical function, say/(9), where ... [Pg.38]

The complex admittance method described here allows data to be analyzed without reference to any particular model. This condition is particularly important at this time, when new data and new concepts are challenging previously accepted concepts. The elucidation of the primary structure of channel proteins (2, 3) has stimulated the development of a number of structurally oriented models (e.g., references 21 and 22). In addition, new physical and mathematical concepts have been brought to bear on the problem of channel gating in excitable membranes. These concepts include... [Pg.421]

The issues associated with understanding EIS also relate to the fact that it demands some knowledge of mathematics, Laplace and Fourier transforms, and complex numbers. The concept of complex calculus is especially difficult for students, although it can be avoided using a quite time-consuming approach with trigonometric functions. However, complex numbers simplify our calculations but create a barrier in understanding complex impedance. Nevertheless, these problems are quite trivial and may be easily overcome with a little effort. [Pg.2]

Transport Models. Many mechanistic and mathematical models have been proposed to describe reverse osmosis membranes. Some of these descriptions rely on relatively simple concepts others are far more complex and require sophisticated solution techniques. Models that adequately describe the performance of RO membranes are important to the design of RO processes. Models that predict separation characteristics also minimize the number of experiments that must be performed to describe a particular system. Excellent reviews of membrane transport models and mechanisms are available (9,14,25-29). [Pg.146]

Gas-liquid-particle operations are of a comparatively complicated physical nature Three phases are present, the flow patterns are extremely complex, and the number of elementary process steps may be quite large. Exact mathematical models of the fluid flow and the mass and heat transport in these operations probably cannot be developed at the present time. Descriptions of these systems will be based upon simplified concepts. [Pg.81]

The use of the Poisson distribution for this purpose predates the statistical overlap theory of Davis and Giddings (1983), which also utilized this approach, by 9 years. Connors work seems to be largely forgotten because it is based on 2DTLC that doesn t have the resolving power (i.e., efficiency or the number of theoretical plates) needed for complex bioseparations. However, Martin et al. (1986) offered a more modem and rigorous theoretical approach to this problem that was further clarified recently (Davis and Blumberg, 2005) with computer simulation techniques. Clearly, the concept and mathematical approach used by Connors were established ahead of its time. [Pg.12]

The non-linear theory of steady-steady (quasi-steady-state/pseudo-steady-state) kinetics of complex catalytic reactions is developed. It is illustrated in detail by the example of the single-route reversible catalytic reaction. The theoretical framework is based on the concept of the kinetic polynomial which has been proposed by authors in 1980-1990s and recent results of the algebraic theory, i.e. an approach of hypergeometric functions introduced by Gel fand, Kapranov and Zelevinsky (1994) and more developed recently by Sturnfels (2000) and Passare and Tsikh (2004). The concept of ensemble of equilibrium subsystems introduced in our earlier papers (see in detail Lazman and Yablonskii, 1991) was used as a physico-chemical and mathematical tool, which generalizes the well-known concept of equilibrium step . In each equilibrium subsystem, (n—1) steps are considered to be under equilibrium conditions and one step is limiting n is a number of steps of the complex reaction). It was shown that all solutions of these equilibrium subsystems define coefficients of the kinetic polynomial. [Pg.48]

A general formula for single catalytic cycles with arbitrary number of members and arbitrary distribution of catalyst material has been derived by Christiansen. Unfortunately, the denominator of his rate equation for a cycle with k members contains k2 additive terms. Such a profusion makes it imperative to reduce complexity. If warranted, this can be done with the concept of relative abundance of catalyst-containing species or the approximations of a rate-controlling step, quasi-equilibrium steps, or irreversible steps, or combinations of these (the Bodenstein approximation of quasi-stationary states is already implicit in Christiansen s mathematics). In some fortunate instances, the rate equation reduces to a simple power law. [Pg.256]

Mathematicians have termed a set of elements in a poset that are all mutually incomparable an anti-chain. (See chapter by Briiggemann and Carlsen, p. 61 and for more detailed mathematics and definitions see Combinatorics and Partially Ordered Sets Dimension Theory by Trotter (Trotter 1992)). If we consider all anti-chains that contain a partition [A] as an element, the complexity of [a] is the number of elements in those antichains (i.e. the cardinality or size of the anti-chains) that have the maximum number of elements, maximum anti-chains. Clearly, this concept can be generalized to any poset, though, as we have seen, the case of the YDL is of particular interest and relevance to physics and chemistry. [Pg.373]

The nature-inspired concept of cellular automata (CAs) was proposed in the 1950s by von Neumann (1951). CAs may be understood as simple mathematical representations of complex systems and their behavior. Since their introduction, CAs have been successfully used in science to model complex systems and processes driven by a large number of interacting, simple, and identical components. However, in the twentieth century, no conceptual designing applications took place. [Pg.372]


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See also in sourсe #XX -- [ Pg.16 , Pg.17 ]

See also in sourсe #XX -- [ Pg.16 , Pg.17 ]




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