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Differentiability exponent

ZINDO/I is based on a modified version of the intermediate neglect of differential overlap (INOOh which was developed by Michael /ern cr of the Quan turn Th cory Project at th e Lin iversity oIFIorida. Zerner s original IXDO/1 used the Slater orbital exponents with a distance dependence for the first rorv transition metals only. (See Thvorel. Chirn. Ada (Bed.) 53, 21-54 (1979).) However, in HyperChem con stan I orbital expon en ts are used for all the available elements, as recommended by. Anderson, Kdwards, and /.erner, /norg. Chern. 25, 2728-2732,1986,... [Pg.294]

The variables are separable, but an integration in closed form is not possible because of the odd exponent. Numerical integration followed by substitution into (4) will provide both A and B as functions of t. The plots, however, are of solutions of the original differential equations with ODE. [Pg.709]

For differential equations with periodic coefficients, the theorems are the same but the calculation of the characteristic exponents meets with difficulty. Whereas in the preceding case (constant coefficients), the coefficients of the characteristic equation are known, in the present case the characteristic equation contains the unknown solutions. Thus, one finds oneself in a vicious circle to be able to determine the characteristic exponents, one must know the solutions, and in order to know the latter, one must know first these exponents. The only resolution of this difficulty is to proceed by the method of successive approximations.11... [Pg.345]

Equation derived from equation number Differential form da dt Integral form kt = Exponents in 7= kam (1 -a)n dr x (—ln(l — a))p Rising temperature expression... [Pg.90]

Particular solutions to Eq. (131) are R(p) = e p/2, where only the negative exponent yields an acceptable function at infinity. This result suggests the substitution Rip) = e pf2Sip), which results in the differential equation... [Pg.271]

The first term with the positive exponent causes the life to increase above Lq, while the second term exerts the opposite effect. We can also see that a temperature differential from case to core in excess of the designed value is considered more harmful than a normal temperature differential (i.e., one that is caused by staying within the current rating). Chemicon models this excess temperature rise rather conservatively as causing a halving of life every 5°C increase, rather than the usual 10°C. [Pg.107]

The most important quantitative measure for the degree of chaotic-ity is provided by the Lyapunov exponents (LE) (Eckmann and Ru-elle, 1985 Wolf et. al., 1985). The LE defines the rate of exponential divergence of initially nearby trajectories, i.e. the sensitivity of the system to small changes in initial conditions. A practical way for calculating the LE is given by Meyer (Meyer, 1986). This method is based on the Taylor-expansion method for solving differential equations. This method is applicable for systems whose equations of motion are very simple and higher-order derivatives can be determined analytically (Schweizer et.al., 1988). [Pg.186]

Linear-variable-differential-transformer (LVDT) transducers, 20 652-653 Linear velocity, exponents of dimensions in absolute, gravitational, and engineering systems, 8 584t Lineatin, 24 473 Line-block coders, 7 691 Line-edge roughness (LER), 15 181 Line exposures, in photography, 19 209-210 Linen... [Pg.524]

The exponent p is then to be determined on the basis of atmospheric conditions. By differentiating Eq. (9.1) with respect to z, p is found from... [Pg.275]

Matrix elements are scalar-valued matrix functions of the exponent matrices Lk- Therefore, the appropriate mathematical tool for finding derivatives is the matrix differential calculus [116, 118]. Using this, the derivations are nontrivial but straightforward. We will only present the final results of the derivations. The reader wishing to derive these formulas, or other matrix derivatives, is referred to the Ref. 116 and references therein. [Pg.414]

On the other hand, it is well known that there is a relationship between Lyapunov exponents and the divergence of the vector field deduced from the differential equations describing a dynamical system. This relation provides a test on the numerical values obtained from the simulation algorithm. This relationship is, according to the definition of Lyapunov exponents ... [Pg.252]

The overall order of a chemical reaction is equal to the sum of the exponents of all the concentration terms in the differential rate expression for a reaction considered in one direction only. For example, if the empirical rate law for a particular chemical reaction was... [Pg.529]

In this approximation the exponent is of order at and terms of order (at)(aic) are omitted. Equation (3.3) is precisely the solution of the differential equation... [Pg.406]

Thirdly one needs a drastic step to turn this integral equation into a differential equation. This is the Markov approximation , which comes in two varieties. The first variety consists in replacing ps(t — t) with ps(t). The error is of relative order rc/rm (where l/rm is the unperturbed rate of change due to S s) and of absolute order a2T2/rm. In this approximation one may as well omit the S s in the exponent of (4.13) and the result is the same as (3.19). The second variety takes the zeroth order variation of ps into account by setting ps(t — r) = e T sps(t). The result is the same as was obtained in (3.14) by means of the interaction representation, and the only requirement is arc <[Pg.444]

The method of CHF-PT-EB CNDO has been used for several organometallic complexes. This method utilizes a coupled Hartree-Fock (CHF) scheme10 applied through the perturbation theory (PT) of McWeeny,11"13 and an extended basis (EB), complete neglect of differential overlap (CNDO/2) wavefunction. The exponents of the basis set are optimized with respect to experimental polarizabilities and second hyperpolarizabili-ties.14,15 A detailed description of the CNDO/2 method may be found in Ref. 16. [Pg.367]

Experimentally observed quantities pertaining to the whole surface, such as the amount of adsorbed substance, heat of adsorption, reaction rate, are sums of contributions of surface sites or, since the number of sites is extremely great, the respective integrals. As increases monotonously with s, each of them can be taken as variable for integration both methods of calculation are used. If is chosen as an independent variable, a differential function of distribution of surface sites with respect to desorption exponents, [Pg.211]

In order to complete the solution of the problem of gas motion under the action of a short impulse, we must not only find the exponents and dimensionless functions, which is accomplished by integrating the ordinary differential equations. We must also determine the numerical coefficients A and B in the formulas. [Pg.114]

The first type, which includes, for example, the problem of strong explosion or propagation of heat in a medium with nonlinear thermal conductivity [3], is characterized by the fact that the exponents are found from physical considerations, from the conservation laws and their dimensionality. In addition, the exponents turn out to be rational numbers. The task of the calculation is to find the dimensionless functions by integration of ordinary differential equations. After this the problem is completely solved, since the numerical constants are determined by normalizing the solution to the conserved quantity (the total energy released in these examples). [Pg.117]

The second type includes, for example, the problem investigated by Gud-erley (cited in [4]) of convergence of a cylindrical shock wave to a line, or of a spherical wave to a point. In this case, just finding the exponent requires integration of ordinary differential equations. The exponent is found from the condition that the integral curve passes through a singular point without this it is impossible to satisfy the boundary conditions. [Pg.117]

This differential rate expression shows that the reaction rate is directly dependent on the concentration of A—the greater is [A], the faster is A converted to B. The reaction is said to be first order with respect to A because the exponent of [A] is 1. [Pg.99]

Two models that have been established to delineate these dual release mechanisms are highlighted here. Interested readers are encouraged to review the extensive literature available to comprehend the underlying drug release process.16,17,19-24 Among all the models developed, the semi-empirical exponent equation has been used widely to differentiate the contributions of both mechanisms16,17 ... [Pg.118]

Mathematical operations have specific rules for the use of mathematical symbols with SI units. A space or a half-high dot represents the multiplication of units a negative exponent, horizontal line, or slash represents the division of units, and if these mathematical symbols appear in the same line, parentheses must differentiate them. The percent sign (%) denotes the number 0.01 or 1/100, so that 1%= 0.01, 30% = 0.30, and so forth. Arabic numerals with the appropriate SI or recognized unit indicate the values of quantities. Commas are not used to separate numbers into groups of three. If more than four digits appear on either side of the decimal point, a space Table 3. Prefixes. separates the groups of three. [Pg.246]

Thus, we have to conclude that, without knowing the physical nature of the frequency dependence of the differential capacitance of a semiconductor electrode, the donor (or acceptor) concentration in the electrode cannot be reliably determined on the basis of the Schottky theory, irrespective of the Mott-Schottky plot presentation format. Therefore, the reported in literature acceptor concentrations in diamond, determined by the Schottky theory disregarding the frequency effect under discussion, must be taken as an approximation only. However, we believe that the o 2 vs. E plot (the more so, when the exponent a approaches 1), or the Ccaic 2 vs. E plot, are more convenient for a qualitative comparison of electrodes made of the same semiconductor material. [Pg.235]


See other pages where Differentiability exponent is mentioned: [Pg.234]    [Pg.318]    [Pg.331]    [Pg.222]    [Pg.82]    [Pg.327]    [Pg.22]    [Pg.187]    [Pg.107]    [Pg.339]    [Pg.16]    [Pg.84]    [Pg.33]    [Pg.86]    [Pg.410]    [Pg.180]    [Pg.167]    [Pg.385]    [Pg.37]    [Pg.352]    [Pg.382]    [Pg.97]    [Pg.1095]    [Pg.103]   
See also in sourсe #XX -- [ Pg.6 ]

See also in sourсe #XX -- [ Pg.6 ]




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