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Classical matrix method

The Classical Matrix Method for Solving the Direct Kinetic Problem... [Pg.41]

The direct problem of chemical kinetics always has an analytical solution if a reaction mathematical model is a linear system of ordinary first-order differential equations. Sequences of elementary first-order kinetic steps, including ones complicated with reversible and competitive steps, correspond to such mathematical models. Let us mark off the classical matrix method firom analytical methods of solving such ODE systems. [Pg.41]

All the enumerated stages of the matrix solution of an ODE system can be, of course, also realized by the Maple suits. However, provided there is the function dso Ive which copes with linear systems without difficulty, using of the classical matrix method is unnecessary. [Pg.45]

Thereby, in the symbolic commands laplace, invlaplace of the Math-cad package we have one more quite reliable instrument for solving the direct problem of chemical kinetics for multi-step reactions described by systems of linear differential equations. The examples of the kinetic equations for some reactions are represented in Table 2.1. Naturally, the classical matrix method can be used to derive these equations. In Maple, capabilities of dsolve are enough for this. [Pg.51]

Deduce analytic expressions for the time-dependences of the concentrations of substances A, B, C and D for given reactions mechanisms using operational or the classic matrix method of solving sets of differential equations. Assume following numeric values for the rate constants (s ) = I2 2 = 1/4 ... [Pg.317]

Using the matrix method of calculation (Li), it is possible to show that the classical partition function of the system is ... [Pg.147]

On the other hand, its should be emphasized that such basic analytical properties as precision, sensitivity and selectivity are influenced by the kinetic connotations of the sensor. Measurement repeatability and reproducibility depend largely on constancy of the hydrodynamic properties of the continuous system used and on whether or not the chemical and separation processes involved reach complete equilibrium (otherwise, measurements made under unstable conditions may result in substantial errors). Reaction rate measurements boost selectivity as they provide differential (incremental) rather than absolute values, so any interferences from the sample matrix are considerably reduced. Because flow-through sensors enable simultaneous concentration and detection, they can be used to develop kinetic methodologies based on the slope of the initial portion of the transient signal, thereby indirectly increasing the sensitivity without the need for the large sample volumes typically used by classical preconcentration methods. [Pg.76]

Classical chemometric methods, that is, the classification and regression presented in Section 4.3.1, are also applied to hyperspectral images.However,XxYx X matrices have to be unfolded into (1 ) 1 matrices before processing. In other words, the three-way OOV array is unfolded into a classical two-way OV matrix. [Pg.418]

The problem of determination of the partition function Z(k, N) for the iV-link chain having the fc-step primitive path was at first solved in Ref. [17] for the case a = c by application of rather complicated combinatorial methods. The generalization of the method proposed in Ref. [17] for the case c> a was performed in Refs. [19,23] by means of matrix methods which allow one to determine the value Z(k,N) numerically for the isotropic lattice of obstacles. The basic ideas of the paper [17] were used in Ref. [19] for investigation of the influence of topological effects in the problem of rubber elasticity of polymer networks. The dependence of the strain x on the relative deformation A for the uniaxial tension Ax = Xy = 1/Va, kz = A calculated in this paper is presented in Fig. 6 in Moon-ey-Rivlin coordinates (t/t0, A ), where r0 = vT/V0(k — 1/A2) represents the classical elasticity law [13]. (The direct Edwards approach to this problem was used in Ref. [26].) Within the framework of the theory proposed, the swelling properties of polymer networks were investigated in Refs. [19, 23] and the t(A)-dependence for the partially swollen gels was obtained [23]. In these papers, it was shown that the theory presented can be applied to a quantitative description of the experimental data. [Pg.10]

Once the weighting factors are calculated, the reconstruction values are obtained by equations 3.3 with simple additions and multiplications. This classic algebraic method, known as matrix inversion, is rigorous and straightforward, but in practice it is employed... [Pg.78]

Example 9 demonstrates classical zoning calculations for radiation pyrometry in furnace applications. Example 10 is a classical furnace design calculation via zoning an enclosure with a diathermanous atmosphere and M = 4. The latter calculation can only be addressed with die matrix method. The results of Example 10 demonstrate the relative insensitivity of zoning to M > 3 and the engineering utility of the SSR model. [Pg.28]

An elegant, general solution for first-order networks has been provided in a classic publication by Wei and Prater [22]. In essence, the mathematics are developed for a reaction system with any number of participants that are all connected with one another by direct first-order pathways. For example, in a system with five participants, each of these can undergo four reactions, for a total of twenty first-order steps. Matrix methods are used to obtain concentration histories in constant-volume batch reactions, and a procedure is described for determination of all rate coefficients from such batch... [Pg.113]

The method adopted to obtain the foree constants from the vibrational frequencies treated the molecule as a system of point masses connected by springs that obeyed Hooke s law, so the system was purely harmonic. The approach was codified in a classic book [3] and is known as the Wilson GF matrix method. The basis of the method is described in 4.2.2 and in more detail in [4,5]. The key equation is ... [Pg.369]

In many cases, too, the semiclassical model provides a quantitative description of the quantum effects in molecular systems, although there will surely be situations for which it fails quantitatively or is at best awkward to apply. From the numerical examples which have been carried out thus far— and more are needed before a definitive conclusion can be reached—it appears that the most practically useful contribution of classical S-matrix theory is the ability to describe classically forbidden processes i.e. although completely classical (e.g. Monte Carlo) methods seem to be adequate for treating classically allowed processes, they are not meaningful for classically forbidden ones. (Purely classical treatments will not of course describe quantum interference effects which are present in classically allowed processes, but under most practical conditions these are quenched.) The semiclassical approach thus widens the class of phenomena to which classical trajectory methods can be applied. [Pg.132]

The classical least squares (CLS) method, also known as the AT-matrix method, extends the application of ordinary least squares as applied to a single independent variable. [Pg.177]


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See also in sourсe #XX -- [ Pg.41 , Pg.42 , Pg.43 , Pg.44 , Pg.51 ]




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Classic methods

Classical methods

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