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Connectivity exponent

Recently Thiel and Voityuk have constructed a workable NDDO model which also includes d-orbitals for use in connection with MNDO, called MNDO/d. With reference to the above description for MNDO/AM1/PM3, it is clear that there are immediately three new parameters Cd, Ud and (dd (eqs. (3.82) and (3.83)). Of the 12 new one-centre two-electron integrals only one (Gjd) is taken as a freely varied parameter. The other 11 are calculated analytically based on pseudo-orbital exponents, which are assigned so that the analytical formulas regenerate Gss, Gpp and Gdd. [Pg.89]

Verhaltnis, n, proportion ratio, rate relation sit iation, connection, circumstance condition, consistency, -anzeiger, m. (Math.) exponent, -gleichheit, /, proportion. verhaltnis-mSssig, a. proportional, proportionate relative commensurable, commensurate. — adv. proportionately, relatively, -widrig, a. disproportionate. [Pg.481]

Figure 32.8 shows the biplot constructed from the first two columns of the scores matrix S and from the loadings matrix L (Table 32.11). This biplot corresponds with the exponents a = 1 and p = 1 in the definition of scores and loadings (eq. (39.41)). It is meant to reconstruct distances between rows and between columns. The rows and columns are represented by circles and squares respectively. Circles are connected in the order of the consecutive time intervals. The horizontal and vertical axes of this biplot are in the direction of the first and second latent vectors which account respectively for 86 and 13% of the interaction between rows and columns. Only 1% of the interaction is in the direction perpendicular to the plane of the plot. The origin of the frame of coordinates is indicated... [Pg.197]

Fig. 10. Experimental values of the gel stiffness S plotted against the relaxation exponent n for crosslinked polycaprolactone at different stoichiometric ratios [59]. The dashed line connects the equilibrium modulus of the fully crosslinked material (on left axis) and the zero shear viscosity of the precursor (on right axis)... Fig. 10. Experimental values of the gel stiffness S plotted against the relaxation exponent n for crosslinked polycaprolactone at different stoichiometric ratios [59]. The dashed line connects the equilibrium modulus of the fully crosslinked material (on left axis) and the zero shear viscosity of the precursor (on right axis)...
In this connection let us remark that in spite of several efforts, the relation between Lyapounov exponents, correlations decay, diffusive and transport properties is still not completely clear. For example a model has been presented (Casati Prosen, 2000) which has zero Lyapounov exponent and yet it exhibits unbounded Gaussian diffusive behavior. Since diffusive behavior is at the root of normal heat transport then the above result (Casati Prosen, 2000) constitutes a strong suggestion that normal heat conduction can take place even without the strong requirement of exponential instability. [Pg.14]

Figure 5.1 illustrates the Fourier transform (FT) of a simple function, viz., a Gaussian. The relatively sharp Gaussian function with the exponent a = 1 depicted in Figure 5.1a, yields a diffuse Gaussian (in dotted line) in momentum space. A flat Gaussian function in position space with a = 0.1, transforms to a sharp one (cf. Figure 5.1b). Connected by an FT, the wave functions in position and momentum... Figure 5.1 illustrates the Fourier transform (FT) of a simple function, viz., a Gaussian. The relatively sharp Gaussian function with the exponent a = 1 depicted in Figure 5.1a, yields a diffuse Gaussian (in dotted line) in momentum space. A flat Gaussian function in position space with a = 0.1, transforms to a sharp one (cf. Figure 5.1b). Connected by an FT, the wave functions in position and momentum...
Further let s consider the question, which parameters define the value a and, hence, the active time value f. As it is known [5], the relation a/p is connected with exponent p at / in the generalized transport equation as follows ... [Pg.245]

In its turn, p and Hurst exponent H are connected between themselves like this [5] ... [Pg.245]

Computer simulation in space takes into account spatial correlations of any range which result in Intramolecular reaction. The lattice percolation was mostly used. It was based on random connections of lattice points of rigid lattice. The main Interest was focused on the critical region at the gel point, l.e., on critical exponents and scaling laws between them. These exponents were found to differ from the so-called classical ones corresponding to Markovian systems irrespective of whether cycllzatlon was approximated by the spanning-tree... [Pg.10]

Thus, for most of the reactions of etr in water-alkaline matrices at reasonable values of the parameters v0, ae, and a, eqn. (7) of Chap. 5 describes with good accuracy the kinetics of the process over a broad interval of observation time. At the same time, for a small number of acceptors [Os02(OH)4 and Br03 ] in water-alkaline matrices the experimentally observed kinetic curves were found to deviate markedly from eqn. (7) of Chap. 5 or values of IV, were obtained that are unreasonable from the viewpoint of the theory of an elementary act of electron tunneling. The reasons for these deviations have not yet been finally made clear. It will only be noted here that they may be connected, for example, with possible errors in measuring the concentration of et r by the optical method in the presence of reaction products that can perhaps have absorption bands in the same spectral region as etr, with the simultaneous presence of several forms of an acceptor in vitreous solutions [104], as well as with deviations of the dependence of the probability VT(R) of tunneling on the distance, R, from a simple exponent of the form of eqn. (3) of Chap. 5 for the reasons discussed in Chap. 3. [Pg.200]

It was later demonstrated that if the reaction mechanism corresponds to scheme (295) and the linear relation between standard Gibbs energy of adsorption and Gibbs activation energy of adsorption is obeyed [see (91)], then the kinetic (305) corresponds in general to the exponential nonuniformity of the surface with even nonuniformity included as a particular case (44). In the general case the exponent m is not equal to transfer coefficient a, but is connected with it according to (143).5... [Pg.252]

In connection with the expansion of the exponent in a series studied by Frank-Kamenetskii [3], a single criterion is sufficient to describe the dependence of the reaction rate on the temperature in the only temperature region of interest to us, that in which the reaction rate is high ... [Pg.276]

Marcus rate theory is useful to rationalize the connection between reactivity and the slope a of Bronsted plots. The derivative of Equation (19) with respect to ArG° is the slope of the Marcus curve, which corresponds to the Bronsted exponent a for a given free energy of reaction ArG°, Equation (20).74 80... [Pg.352]

The basins of attraction of the coexisting CA (strange attractor) and SC are shown in the Fig. 14 for the Poincare crosssection oyf = O.67t(mod27t) in the absence of noise [169]. The value of the maximal Lyapunov exponent for the CA is 0.0449. The presence of the control function effectively doubles the dimension of the phase space (compare (35) and (37)) and changes its geometry. In the extended phase space the attractor is connected to the basin of attraction of the stable limit cycle via an unstable invariant manifold. It is precisely the complexity of the structure of the phase space of the auxiliary Hamiltonian system (37) near the nonhyperbolic attractor that makes it difficult to solve the energy-optimal control problem. [Pg.504]

Several authors have published the method for determining molar masses of DADMAC polymers, primarily in connection with practical applications [1]. In Table 11 intrinsic viscosity-molar mass relations of PDADMAC are summarized in the form of the Mark-Kuhn-Houwink-Sakurada (MKHS) relationship. The relatively high exponent of the relationships is attributed to the greater chain stiffness in comparison with vinyl backbones. One has to look quite skeptically at the values from reference [59] given its deviation from the remainder of the published data. [Pg.165]

This, however, confronts us with the fundamental problem expressed by Beeck as a Challenge to the physicist, i.e., how to account for the fact that the activity differences are located in the temperature-independent factors. The problem as stated by Beeck appeared the more mysterious, since it was reported for films that the dependency of the rate on the pressures of the reactants was essentially the same for all the metals discussed here, being first order in the hydrogen pressure and zero order in the ethylene pressure. Our results, however, show differences that appear significant. The exponents connected with the hydrogen and ethylene pressure as they occur in Equation (42) were calculated in the same way as indicated for Ni and tabulated in Table IX. There appears to be a trend in n, the exponent... [Pg.312]


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