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Mathematics exponents

Guida R and Zinn-Justin J 1998 Critical exponents of the A/-vector model J. Phys. A Mathematical and General 31 8103-21... [Pg.662]

In the complex mathematical representation, quadrature means that, at the (s + 1) wave mixing level, the product of. s input fields constituting the. sth order generator and the signal field can be organized as a product of (s + l)/2 conjugately paired fields. Such a pair for field is given by = ,One sees that the exponent... [Pg.1187]

The intercept on the adsorption axis, and also the value of c, diminishes as the amount of retained nonane increases (Table 4.7). The very high value of c (>10 ) for the starting material could in principle be explained by adsorption either in micropores or on active sites such as exposed Ti cations produced by dehydration but, as shown in earlier work, the latter kind of adsorption would result in isotherms of quite different shape, and can be ruled out. The negative intercept obtained with the 25°C-outgassed sample (Fig. 4.14 curve (D)) is a mathematical consequence of the reduced adsorption at low relative pressure which in expressed in the low c-value (c = 13). It is most probably accounted for by the presence of adsorbed nonane on the external surface which was not removed at 25°C but only at I50°C. (The Frenkel-Halsey-Hill exponent (p. 90) for the multilayer region of the 25°C-outgassed sample was only 1 -9 as compared with 2-61 for the standard rutile, and 2-38 for the 150°C-outgassed sample). [Pg.216]

From this kind of continuum mechanics one can move further towards the domain of almost pure mathematics until one reaches the field of rational mechanics, which harks back to Joseph Lagrange s (1736-1813) mechanics of rigid bodies and to earlier mathematicians such as Leonhard Euler (1707-1783) and later ones such as Augustin Cauchy (1789-1857), who developed the mechanics of deformable bodies. The preeminent exponent of this kind of continuum mechanics was probably Clifford Truesdell in Baltimore. An example of his extensive writings is A First Course in... [Pg.47]

Logarithm The exponent that indicates the power to which a number is raised to produce a given number. Thus, as an example, 1000 to the base of 10 is 3. This type of mathematics is used extensively in computer software. [Pg.638]

Data given in Tables 1-6 clearly show a significant dependence of P2 and p4 on amine concentration, that is, at least one of the apparent rate constants kj contains a concentration factor. Thus, according to the mathematical considerations outlined in the Analysis of Data Paragraph, both p2, P4 exponents and the derived variables -(P2 + p)4> P2 P4 ind Z (see Eqns. 8-12) are the combinations of the apparent rate constants (kj). To characterize these dependences, derived variables -(p2+p)4, P2 P4 and Z (Eqns. 8,11 and 12) were correlated with the amine concentration using a non-linear regression program to find the best fit. Computation resulted in a linear dependence for -(p2 + p)4 and Z, that is... [Pg.268]

The abbreviation log stands for logarithm. In mathematics, a logarithm is the power (also called an exponent) to which a number (called the base) has to be raised to get a particular number. In other words, it is the number of times the base (this is the mathematical base, not a chemical base) must be multiplied times itself to get a particular number. For example, if the base number is 10 and 1,000 is the number trying to be reached, the logarithm is 3 because 10 x 10 x 10 equals 1,000. Another way to look at this is to put the number 1,000 into scientific notation ... [Pg.31]

Onsager and Machlup [32] gave an expression for the probability of a path of a macrostate, p[x]. The exponent may be maximized with respect to the path for fixed end points, and what remains is conceptually equivalent to the constrained second entropy used here, although it differs in mathematical detail. The Onsager-Machlup functional predicts a most likely terminal velocity that is exponentially decaying [6, 42] ... [Pg.79]

The square brackets refer to the concentration of the species inside. Note that the concentrations are multiplied or divided, not added or subtracted, and the concentrations of the products are in the numerator. The coefficients in the balanced chemical equation have become exponents in this mathematical equation. [Pg.232]

Sorenson chose to write the concentration of hydrogen ions as a power of 10. For example, an aqueous solution that contained 5.00 x 10-2 M hydrogen ions (H+) would be denoted as containing the mathematically equivalent value of 10-130 M H+ ions. Sorenson designated the Ph or pH of the solution as the numerical value of the negative exponent of 10. Thus, a pH of 1.30 would be ascribed to the solution. In other words,... [Pg.73]

It is important to note that the exponents of x for centrosymmetric molecules cannot be even numbers (i.e. materials composed by centrosymmetric molecules cannot generate effects of second order, fourth order, etc.). In fact, if one applies a field +E, the first non-linear term would induce a polarization of + fl-E2 (or + y 2)-E2). If one were to apply instead a field of-.E, the mathematical expression would lead to an induced polarization again of + fi-E2, whereas, as shown in Figure 38a, the induced polarization is -fi-E2. This contradiction can only be resolved if / (or /2)) = 0. [Pg.200]

Unfortunately, extending Hylleraas s approach to systems containing three or more electrons leads to very cumbersome mathematics. More practical approaches, known as explicitly correlated methods, are classified into two categories. The first group of approaches uses Boys Gaussian-type geminal (GTG) functions with the explicit dependence on the interelectronic coordinate built into the exponent [95]... [Pg.237]

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]

The pressure exponent (n) is the characteristic of a specific propellant and also depends on the pressure range. For DB propellants, it is in the range from 0.2 to 0.5 but AP-based composite propellants exhibit relatively low values (0.1 to 0.4). The mathematical derivations clearly show that the value of n can never exceed 1 and a value close to 0 (zero) is always preferred from safety considerations. [Pg.222]

The last entry in Table 10.1 is the least well defined of those listed. This is of little importance to us, however, since our interest is in attraction, and the final entry in Table 10.1 always corresponds to repulsion. The reader may recall that so-called hard-sphere models for molecules involve a potential energy of repulsion that sets in and rises vertically when the distance of closest approach of the centers equals the diameter of the spheres. A more realistic potential energy function would have a finite (though steep) slope. An inverse power law with an exponent in the range 9 to 15 meets this requirement. For reasons of mathematical convenience, an inverse 12th-power dependence on the separation is frequently postulated for the repulsion between molecules. [Pg.469]

In Chapter 11 (Sections 11.4 and 11.6) we implicitly anticipated that the ion opposite in charge from the wall plays the predominant role in the double layer, the central observation of the Schulze-Hardy rule. This enters the mathematical formalism of the Gouy-Chapman theory in Equation (11.52), in which a Boltzmann factor is used to describe the relative concentration of the ions in the double layer compared to the bulk solution. For those ions that have the same charge as the surface (positive), the exponent in the Boltzmann factor is negative. This reflects the Coulombic repulsion of these ions from the wall. Ions with the same charge as the surface are thus present at lower concentration in the double layer than in the bulk solution. [Pg.591]

A common mathematical assumption is that the dependence of the order parameter e2 on the path parameter r can be described by a critical exponent relationship of the form [see, e.g., H. E. Stanley. Introduction to Phase Transitions and Critical Phenomena (Oxford University Press, New York, 1971)]... [Pg.385]

To understand how this shorthand notation works, consider the large number 50,000,000. Mathematically this number is equal to 5 multiplied by 10 X 10X 10X 10X 10 X 10 X 10 (check this out on your calculator). We can abbreviate this chain of numbers by writing all the 10s in exponential form, which gives us the scientific notation 5 X 107. (Note that 107 is the same as lOx lOx 10x lOx 10 X 10 X 10. Table A. 1 shows the exponential form of some other large and small numbers.) Likewise, the small number 0.0005 is mathematically equal to 5 divided by 10 X 10 x 10 X 10, which is 5/104. Because dividing by a number is exactly equivalent to multiplying by the reciprocal of that number, 5/104 can be written in the form 5 X 10-4, and so in scientific notation 0.0005 becomes 5 X 10-4 (note the negative exponent). [Pg.674]

To use the scientific notation of numbers in mathematical operations, we must remember the laws of exponents. [Pg.8]

The mathematics are not very complicated but quite cumbersome and are not be presented here. This technique seems quite elegant. However, it cannot be better than the equations used the Equations (5.2-13) and (5.2-14) contain some constants whose values are empirical (A, B, the exponents 2.8, 2.43...) the permeability is not always well known, and it is not certain that Leverett s approach remains valid in the case of cocurrent flow. [Pg.270]

The problem of a kinematic dynamo in a steady velocity field can be treated mathematically as a problem of the effect of a small diffusion or round-off error on the Kolmogorov-Sinai entropy (or Lyapunov exponent) of a dynamical system which is specified by the velocity field v. This problem, on which Ya.B. worked actively, therefore has a general mathematical nature as well, and each step toward its solution is simultaneously a step forward in several seemingly distant areas of modern mathematics. [Pg.51]

The existence of two types of self-similar solutions, explicitly formulated by Ya.B. for the first time, stimulated extensive studies to clarify the general character of the difference between them and to apply the concept of self-similar solutions of the second kind to various problems in mathematical physics. The present state of the problem can be found in a monograph by G. I. Barenblatt.6 We note also the existence of an exact analytic solution with a rational self-similarity exponent when the adiabatic index is equal to 7/5.7... [Pg.119]

Notice how numbers that are either very large or very small are indicated in Table 1.4 using an exponential format called scientific notation. For example, the number 55,000 is written in scientific notation as 5.5 X 104, and the number 0.003 20 as 3.20 X 10 3. Review Appendix A if you are uncomfortable with scientific notation or if you need to brush up on how to do mathematical manipulations on numbers with exponents. [Pg.11]

The inclusion of fluctuations severely complicates the mathematical analysis of physical models and only some simple models can be solved exactly. For these models, however, the results give critical exponents that agree with well-established experimental values. [Pg.109]


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See also in sourсe #XX -- [ Pg.4 , Pg.6 , Pg.15 , Pg.16 , Pg.17 ]




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Exponents

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