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Reaction graph matrix

Calculation of the coefficients dt for a given matrix is a very laborious process. We will give a method to calculate these coefficients proceeding directly from the complex reaction graph. Like a steady-state kinetic equation, a characteristic polynomial will be represented in the general (struc-turalized) form ... [Pg.252]

Proof It suffices to prove that the sum of all the feth order minors amounting to the coefficient of /. is at the same time equal to the sum of the weights for all the (n - )-spanning trees of the reaction graphs. At k = 0 the coefficient of 1° amounts to the B(c) matrix determinant. Since, according to the conservation law, any diagonal element of B(c) satisfies the equality... [Pg.252]

The graphs in Figure 5-23 are convincing. The top panel displays the original data for a simple first order reaction A—>B. The next panel shows the same data after the addition of a substantial amount of noise. The third panel features the reconstructed matrix Y = USV with 2 eigenvectors. Clearly a substantial amount, but not all, of the noise, was removed. [Pg.244]

In the chemical reaction networks that we study, there is no small parameter with a given distribution of the orders of the matrix nodes. Instead of these powers of we have orderings of rate constants. Furthermore, the matrices of kinetic equations have some specific properties. The possibility to operate with the graph of reactions (cycles surgery) significantly helps in our constructions. Nevertheless, there exists some similarity between these problems and, even for... [Pg.110]

Isal Standard addition graph. An assay for substance X is based on its ability to catalyze a reaction that produces radioactive Y. The quantity of Y produced in a fixed time is proportional to the concentration of X in the solution. An unknown containing X in a complex, unknown matrix with an initial volume of 50.0 mL was treated with increments of standard 0.531 M X and the following results were obtained. Prepare a graph of Equation 5-9 and find [X]... [Pg.95]

A category of reactions with a characteristic irreducible R-matrix is a set of basis reactions. The basis reactions correspond to the traditional classification of organic reactions . A basis reaction is best characterized in graph theoretical terms (ref. 13). The educts and the products of a basis reaction are expressed by a graph (see Fig. 7.2) whose nodes correspond to the reactive centers and whose lines indicate the bond orders of the covalent bonds that are directly affected by the reaction. The... [Pg.140]

The characteristic roots are determined by transforming experimental compositions along appropriate reaction paths into the B system of coordinates. Equations (44) and (46) are used to compute the matrix from the matrix X determined from the straight line reaction paths and the equilibrium composition. Each observed composition (<) is transformed by the matrix X into 3(0 [Eq- (40)]- The decay of each 6, with time is given by the set of Eqs. (27) and the value of — X, can be determined from the slope of the straight line obtained from a graph of In bj vs time. [Pg.231]

This matrix T is used to calculate compositions for a pure CTs-2-butene initial composition [Eq. (81)]. The points obtained are shown by o in Fig. 32. As can be seen they lie on the true reaction path within the accuracy of the graph. [Pg.310]

As follows from eqns. (9) and (10), the Bj matrix contains the entire structural information on the reaction mechanism (informa tion on the graph structure). Each linear or non linear mechanism... [Pg.85]

Polymerised preformed [(N,N -dimethyl-l,2-diphenylethane diamine)2Rh] complex allows us to obtain enantioselective material. We have then shown that it is possible to imprint an optically pure template into the rhodium-organic matrix and to use the heterogeneous catalyst in asymmetric catalysis with an obvious template effect. The study of yield versus conversion graphs has shown that the mechanism occurs via two parallel reactions on the same site without any inter-conversion of the final products. Adjusting the cross-linker ratio at 50/50 allows us to find a compromise between activity and selectivity. Phenyl ethyl ketone (propiophenone) was reduced quantitatively in 2 days to (R)-l-phenyl propanol with 7tf% enantiomeric excess We have then shown that the imprinting effect is obvious for molecules related in structure to the template (propiophenone, 4 -trifluoromethyl acetophenone). It is not efficient if the structure of the substrate is too different to that of the template. [Pg.521]

As all steps (equilibria) are reversible (forwards and backwards) and catalized by proton (involving protonations and deprotonations), the complicated reaction matrix involves in the natural series 48 aglucones, 92 equilibria and 368 elementary steps, in the dihydro series 24 aglucones, 40 equilibria and 160 elementary steps. Although any of these structures and transformations can not be excluded, by graph analysis the shortest rational pathways were found for the interpretation of the events. The results could be used for the investigation of other cases in the bioorganic chemistry of indole and related alkaloids, too (see later). [Pg.109]

A model which complies with our precondition is the Ugi-Dugundji model. Reactants and products are represented by their connectivity matrix and the reaction by simply subtracting the two matrices mathematically. The R-matrix represents the changes in bond order during the reaction and consists of a single graph. [Pg.386]

The route method allows to overcome the above-mentioned lack and to determine the relation between a rate of a composite substance s formation, elementary and final reactions and the rates on the routes. In this sense the presented method more fully reflects the kinetics of a chemical process than other methods, is more visible, convenient and needs only an elementary knowledge of the matrix theory and the theory of graphs. [Pg.36]

Among many techniques used to obtain skeletons of larger mechanisms, in what follows we discuss the Direct Relation Graph (DRG) technique, coupled with Depth First Search (DFS) technique, the Sensitivity Analysis of the Jacobian matrix for the chemical system, the Intrinsic Low-Dimensional Manifold (ILDM) technique, the Reaction Diffusion Manifolds (REDIM technique) and the flamelet technique. Among these, the flamelet technique is preferred for writing the simplified chemical system for premixed flames and diffusion flames presented in the following sections. [Pg.73]

Example 2.10. The matrix ID = (D(Gj, Gj)) of the reaction distances between graphs from 2,2 simply constructed from... [Pg.29]

Some types of connection table, or connectivity matrix, have been specifically designed for analysi.s using graph-theoretical techniques, and the so-called Dgundji-Ugi model of constitutional chemistry utilizes bond-electron matrices , which are able to represent free electrons and are thus of particular value in computer analysis of chemical reactions. Recently, Bauerschmidt and Gasteiger have extended some of these ideas in developing an object-oriented representation of chemical species. [Pg.2821]


See other pages where Reaction graph matrix is mentioned: [Pg.253]    [Pg.14]    [Pg.3185]    [Pg.846]    [Pg.153]    [Pg.277]    [Pg.179]    [Pg.217]    [Pg.15]    [Pg.312]    [Pg.255]    [Pg.65]    [Pg.108]    [Pg.78]    [Pg.85]    [Pg.217]    [Pg.48]    [Pg.217]    [Pg.74]    [Pg.19]    [Pg.314]    [Pg.64]    [Pg.155]    [Pg.219]    [Pg.105]    [Pg.439]    [Pg.2902]    [Pg.68]   
See also in sourсe #XX -- [ Pg.12 ]




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