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A Redefinition of

As in Example 10.1, equality of the reaction rates plus the site balance gives four independent equations. Combining them allows a solution for while eliminating the surface concentrations [S], [AS], and [PS]. After much algebra and a redefinition of constants,... [Pg.357]

Values of e are correlated by the Op constants in accord with eq. (61) (119, 120). Kawabata, Tsuruta, and Furukawa (121) have proposed a revised form of the Price-Alfrey equation based on the definition e = 0 for styrene. On the basis of this redefinition, they have calculated a new set of Q values. These Q values are linear in the Hammett 0 constants. It is not clear from their paper whether this linear relationship is for substituents directly bonded to the carbon-carbon double bond or whether it is applicable only to Q values for substituted styrenes. Charton and Capato (119) were unable to obtain significant correlations between any a constants and the q values of Schwan and Price (117). Zutty and Burkhart (122) have proposed a redefinition of the Price-Alfrey equation based on ethylene as the reference system with Qo and e defined as 1 and 0, respectively. [Pg.124]

Thus, the initial value of the initiator concentrations, [Il]° and [I2]°, are calculated with Equation 15, for given values of the initial loading, feed rates, temperature, and time for the main semi-batch step, and [M]° is fixed according to experimental data from the base case semi-batch step. The nonlinear differential equation for [M] in terms of [II] and [I2] is given by Equation 16. Equation 10, with a redefinition of terms, is the differential equation mass balance for [II] and [12]. In the finishing step, only one of the initiators would be added for residual monomer reduction. Thus, Qm = 0,... [Pg.317]

Clericuzio, Antonio. A redefinition of Boyle s chemistry and corpuscular philosophy. Ann Sci 47 (1990) 561-589. [Pg.253]

We wish to mention the recent proposal for a redefinition of Kelvin in terms of mechanical units through the Boltzmann constant [6-7] the Kelvin should be defined as the unit of thermodynamic temperature such that the value of the Boltzmann constant is 1.3806505 x 10 23 JK 1 exactly. Of course, this value of the Boltzmann constant should be consistent with a thermodynamic temperature of the triple point of water of 273.16 K. [Pg.191]

Since the original problem is bilinear, a redefinition of variables was performed to transform it into a linear one, according to the strategy described in Section 4.3. [Pg.107]

There is a continual tendency for the values of cr/ and aR (and other substituent chemical shifts for a series of mono-substituted benzenes in very dilute solution in cyclohexane, carbon tetrachloride or deuteriochloroform were the basis for a redefinition of the aR scale and some amendment of a R values. However, the value for the nitro group was confirmed as 0.15. [Pg.504]

Considerable discussion of reparameterization and examples of its usefulness have been published (B3, B8, B12, Gl, G2, M7). Although several specific techniques are useful, one reparametrization of kinetic models often necessary is a redefinition of the independent variables so that the center of the new coordinate system is near that of the experimental design. In particular, the exponential parameter... [Pg.121]

The mathematical details of carrying out such a redefinition of coordinate system, termed a canonical transformation, have been presented elsewhere in detail (D2). [Pg.156]

Corrected from [2], within which the definition improperly attempts a redefinition of the terms sol and gel. The definition proposed here is recommended for its precision through cross-reference to the properly defined terms. [Pg.233]

Recent unparalleled changes in our society, in science, and in the economy are contributing to a redefinition of what a college education in chemistry should look like. The educational goal of knowing the stracture of the discipline is being subsumed... [Pg.139]

Our insights into Boyles chemical attitudes have been recently enlarged by the following careful studies Antonio Clericuzio, A Redefinition of Boyle s Chemistry and Corpuscular Philosophy, Ann. Sci. 47 (1990) 561-589 and Michael Hunter, ed. Robert Boyle Reconsidered (Cambridge New York Cambridge University Press, 1994), 10. [Pg.9]

A redefinition of all-American a global population on the move city to city country to country... [Pg.9]

Even for d < 4 the question of existence of the continuous chain limit is not completely trivial. The problem is most easily analyzed by taking a Laplace transform with respect to the chain length, which results in the held theoretic representation of polymer theory. In field theory it is not hard to show that the limit — 0 can be taken only after a so-called additive renormalization we first have to extract some contributions which for — 0 would diverge. The extracted terms can be absorbed into a 1 renormalization he. a redefinition of the parameters of the model. Transfer riling back to polymer theory we find that this renormalization just shifts the chemical potential per segment. We thus can prove the following statement after an appropriate shift of the chemical potential the continuous chain limit for d < 4 can be taken order by order in perturbation theory. In this sense the continuous chain model or two parameter theory are a well defined limit of our model of discrete Gaussian chains. [Pg.104]

X will be called the scaling parameter, obeying 0 < A < 1. Note that the dimensionless functions A(.can depend on the length scale A) only via the ratio A = Aj/Al- Note further that the functions A rind B art independent of n.f> The mapping represents a redefinition of the microstructure, and as such should be independent of the total chain length. [Pg.128]

To summarize, in constructing our model in principle we should start from the highest, interaction 0IAJ p = po included, subtracting it by all terms p < po so that the remainder generates corrections obeying the estimate (10.1). The subtracted terms are to be absorbed into a redefinition of the /J p < pm We then proceed the same way with 3. 0 i, etc. We finally reach a two-body interaction 0ct which differs from 02 by contributions extracted from all / /4,p > 2. This in turn has to be subtracted by a one-body contribution, which is absorbed into the segment chemical potential. [Pg.160]

In Chap. 8 we have constructed the renormalization group, starting from bare perturbation theory for the discrete chain model. This expansion involves nonuniversal microstructure corrections which we will now absorb into renormalization factors, introduced via a redefinition of the interaction constant and the chain length, According to Eq. (11.1) we write... [Pg.182]

Thus different renormalization schemes are related by a so-called finite renormalization, which amounts to a redefinition of the renormalized parameters, or to a different parameterization of the field theoretic manifold, equivalently ... [Pg.201]

The first term exists for er —> 0, with corrections of order a ln(<7 2). The second integral yields a contribution of order ln(cr 2). Since it is independent of p, Tj it can be absorbed into a redefinition of the vertex, i.e. into the first diagram of Fig. 11,1b. In standard field theoretic notation we write... [Pg.203]

In the vicinity of x1 a shift in energy means only a redefinition of x, so one may suppose without the loss of generality that E = 0. Then the solution of the Schrodinger equation, near the right turning point is expressed via the Airy functions ... [Pg.89]

Equations (1.14) and (1.15) contain divergent terms that are independent of the particles positions. These terms occur whenever r - r( and represent the electrostatic interaction of each particle with itself. However, because these terms are independent of the particles positions, subtracting them from the electrostatic energy is equivalent to a simple redefinition of the zero-point energy of the particles. Since all forces in nature derive from changes in energy, such a redefinition of the zero point of energy is of no dynamical consequence. [Pg.4]

A series of questions raised by the above ambiguities may be helpful to formulate a redefinition of zinc deficiency. Initially four questions can be raised. They are (1) How can zinc deficiency be defined (2) Why do patients with subacute zinc deficiency, exhibit taste and smell dysfunction as their major, often their only, symptom complex (3) What is the meaning of the wide range of zinc absorption in patients with subacute zinc deficien-... [Pg.93]

Here, as in the discussion of simple molecules, we consider the two hybrids that make up the bond to be orthogonal, that is, = 0, so that there is no term in u, U2 in the denominator. We shall see in Appendix B that this is permissible since the two effects that nonorthogonality has can be absorbed in a redefinition of the covalent and polar energies and in a contribution to the overlap interaction between atoms, which is discussed in Chapter 7. Similarly, we have neglected the more complicated aspects of electron-electron interaction, treating it instead in terms of an average potential associated with each electron. The neglect of... [Pg.68]


See other pages where A Redefinition of is mentioned: [Pg.477]    [Pg.469]    [Pg.427]    [Pg.420]    [Pg.279]    [Pg.59]    [Pg.490]    [Pg.110]    [Pg.239]    [Pg.43]    [Pg.9]    [Pg.54]    [Pg.103]    [Pg.156]    [Pg.160]    [Pg.184]    [Pg.203]    [Pg.420]    [Pg.42]    [Pg.200]    [Pg.469]    [Pg.174]    [Pg.1]    [Pg.83]   


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Redefinition

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