While Becker and Doting obtained a more complex function in place of Z, its numerical value is about equal to Z, and it turns out that the exponential term, which is the same, is the most important one. Thus the complete expression is... [Pg.331]

The tln-ee systems share a coimnon property 9, the numerical value of the tln-ee functions /, /p and/, which can be called the empirical temperature. The equations (A2.1.3) are equations of state for the various systems,... [Pg.325]

The surfaces in which the paths satisfying the condition = 0 must lie are, thus, surfaces of constant entropy they do not intersect and can be arranged in an order of increasing or decreasmg numerical value of the constant. S. One half of the second law of thennodynamics, namely that for reversible changes, is now established. [Pg.335]

During initialization and final analysis of the QCT calculations, the numerical values of the Morse potential paiameters that we have used aie given as... [Pg.56]

Wp, i— 1,2 are potentials of the same functional form as the t/, parameters but defined in terms of a different set of parameters / and p, which replace g and k, respectively. The numerical values for these four parametei s are [135]... [Pg.730]

The CIF format not only defines its dictionary of available data names, but restricts the STAR file syntax as well. For example, lines may not exceed 80 characters and data names can contain a maximum of 32 characters. Furthermore, the CIF dictionaiy specifies default units for numeric fields that represent numeric values with units. If the data item is not stored in the default units, then the units code is appended to the data name. Thus cell length a and cell length a pm represent the dimensions ofthe unit cell in Angstrom (the default units conforming to the SI Standard) and picomclcrs, respectively. [Pg.122]

The network is initialized, and all the weights of the neurons obtain numerical values, in most cases random numbers. [Pg.456]

Note that the constants must be defined equal to their numerical values (defined = is on the keyboard). These definitions must be above the integral you wish to solve. Mathcad operates top down. Mathcad produces the same value for the integral that we obtained from TableCurve. This calculation is redundant with the calculations already performed in this section to inboduce new software by solving a problem for which we already know the answer. [Pg.28]

In quantum mechanics, the eigenvalues of an operator represent the only numerical values that can be observed if the physical property corresponding to that operator is measured. Operators for which the eigenvalue spectrum (i.e., the list of eigenvalues) is discrete thus possess discrete spectra when probed experimentally. [Pg.566]

This section gives a listing of some basis sets and some notes on when each is used. The number of primitives is listed as a simplistic measure of basis set accuracy (bigger is always slower and usually more accurate). The contraction scheme is also important since it determines the basis set flexibility. Even two basis sets with the same number of primitives and the same contraction scheme are not completely equivalent since the numerical values of the exponents and contraction coefficients determine how well the basis describes the wave function. [Pg.85]

Molecular descriptors must then be computed. Any numerical value that describes the molecule could be used. Many descriptors are obtained from molecular mechanics or semiempirical calculations. Energies, population analysis, and vibrational frequency analysis with its associated thermodynamic quantities are often obtained this way. Ah initio results can be used reliably, but are often avoided due to the large amount of computation necessary. The largest percentage of descriptors are easily determined values, such as molecular weights, topological indexes, moments of inertia, and so on. Table 30.1 lists some of the descriptors that have been found to be useful in previous studies. These are discussed in more detail in the review articles listed in the bibliography. [Pg.244]

The C-H spin couplings (Jen) have been dealt with in numerous studies, either by determinations on samples with natural abundance (122, 168, 224, 231, 257, 262, 263) or on samples specifically enriched in the 2-, 4-, or 5-positions (113) (Table 1-39). This last work confirmed some earlier measurements and permitted the determination for the first time of JcH 3nd coupling constants. The coupling, between a proton and the carbon atom to which it is bonded, can be calculated (264) with summation rule of Malinovsky (265,266), which does not distinguish between the 4- and 5-positions, and by use of CNDO/2 molecular wave functions the numerical values thus - obtained are much too low, but their order agrees with experiment. The same is true for Jch nd couplings. [Pg.79]

The friction coefficient determines the strength of the viscous drag felt by atoms as they move through the medium its magnitude is related to the diffusion coefficient, D, through the relation Y= kgT/mD. Because the value of y is related to the rate of decay of velocity correlations in the medium, its numerical value determines the relative importance of the systematic dynamic and stochastic elements of the Langevin equation. At low values of the friction coefficient, the dynamical aspects dominate and Newtonian mechanics is recovered as y —> 0. At high values of y, the random collisions dominate and the motion is diffusion-like. [Pg.94]

The digits in parentheses following a numerical value represent the standard deviation of that value in terms of the final listed digits. [Pg.78]

Here 0p and 0 correspond to the terms in r" and respectively in Equation (1.8) as already pointed out, these contributions are always present, whereas the electrostatic energies 0, and may or may not be present according to the nature of the adsorbent and the adsorptive. In principle. Equation (1.16) could be used to calculate the numerical value of the interaction potential as a function of the distance z of any given molecule from the surface of a chosen solid. In practice, however, the scope has to be limited to systems composed of a simple type of gas molecule and... [Pg.7]

The numerical values of and a, for a particular sample, which will depend on the kind of linear dimension chosen, cannot be calculated a priori except in the very simplest of cases. In practice one nearly always has to be satisfied with an approximate estimate of their values. For this purpose X is best taken as the mean projected diameter d, i.e. the diameter of a circle having the same area as the projected image of the particle, when viewed in a direction normal to the plane of greatest stability is determined microscopically, and it includes no contributions from the thickness of the particle, i.e. from the dimension normal to the plane of greatest stability. For perfect cubes and spheres, the value of the ratio x,/a ( = K, say) is of course equal to 6. For sand. Fair and Hatch found, with rounded particles 6T, with worn particles 6-4, and with sharp particles 7-7. For crushed quartz, Cartwright reports values of K ranging from 14 to 18, but since the specific surface was determined by nitrogen adsorption (p. 61) some internal surface was probably included. f... [Pg.36]

Calculations of the interaction energy in very fine pores are based on one or other of the standard expressions for the pair-wise interaction between atoms, already dealt with in Chapter 1. Anderson and Horlock, for example, used the Kirkwood-Miiller formulation in their calculations for argon adsorbed in slit-shaped pores of active magnesium oxide. They found that maximum enhancement of potential occurred in a pore of width 4-4 A, where its numerical value was 3-2kcalmol , as compared with 1-12, 1-0 and 1-07 kcal mol for positions over a cation, an anion and the centre of a lattice ceil, respectively, on a freely exposed (100) surface of magnesium oxide. [Pg.207]

The numerical value of the exponent k determines which moment we are defining, and we speak of these as moments about the value chosen for M. Thus the mean is the first moment of the distribution about the origin (M = 0) and is the second moment about the mean (M = M). The statistical definition of moment is analogous to the definition of this quantity in physics. When Mj = 0, Eq. (1.11) defines the average value of M this result was already used in writing Eq. (1.6) with k = 2. [Pg.37]

Numerical values of sinh x versus x are tabulated in standard sources (e.g.. The Handbook of Tables for Mathematics, Chemical Rubber Company) and the tables can be used to evaluate either sinh x or sinh" y. [Pg.96]

Although it is easy to discuss free volume, it is necessary to come up with a numerical value for this quantity in order to test these concepts. There is... [Pg.253]

Table 4.4 Some Polymers Ranked in Order of Decreasing Tg Values, Along with Numerical Values for Quantities Appearing in the Dolittle Equation... |

Table 8.4 lists numerical values for the quantity in brackets for the required... [Pg.572]

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