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The Physical Basis

Exhaustive reviews dealing with the applications of electron transfer theories to biological systems have been published recently [4,22], and should be consulted for a general presentation of electron transfer processes as well as detailed mathematical developments. Shorter reviews are also available [23, 24]. In this section, we review the physical basis of the formalism generally used in the case of [Pg.5]

All through this chapter, we have avoided the terminology electron transfer by tunneling which is rather confusing though it often appears in the literature [14]. The nature of the different tunneling effects involved in electron transfer processes is discussed in the previously cited reviews [4, 22, 23]. [Pg.6]


The question of determination of the phase of a field (classical or quantal, as of a wave function) from the modulus (absolute value) of the field along a real parameter (for which alone experimental determination is possible) is known as the phase problem [28]. (True also in crystallography.) The reciprocal relations derived in Section III represent a formal scheme for the determination of phase given the modulus, and vice versa. The physical basis of these singular integral relations was described in [147] and in several companion articles in that volume a more recent account can be found in [148]. Thus, the reciprocal relations in the time domain provide, under certain conditions of analyticity, solutions to the phase problem. For electromagnetic fields, these were derived in [120,149,150] and reviewed in [28,148]. Matter or Schrodinger waves were... [Pg.104]

H. D. Zeh, The Physical Basis of the Direction of Time, Springer-Verlag, Berlin, 1992. [Pg.172]

The physical basis for peak splitting mil dichloroethane can be explained with the aid of Figure 13 13 which examines how the chemical shift of the methyl protons IS affected by the spin of the methme proton There are two magnetic environments for... [Pg.536]

The relationship between the stmcture of a molecule and its physical properties can be understood by finding a quantitative stmcture—property relation- ship (QSPR) (10). A basis set of similar compounds is used to derive an equation that relates the physical property, eg, melting poiat or boiling poiat, to stmcture. Each physical property requires its own unique QSPR equation. The compounds ia the basis set used for QSPRs with pyridines have sometimes been quite widely divergent ia respect to stmctural similarity or lack of it, yet the technique still seems to work well. The terms of the equation are composed of a coefficient and an iadependent variable called a descriptor. The descriptors can offer iasight iato the physical basis for changes ia the physical property with changes ia stmcture. [Pg.324]

P. A. Redhead, J. P. Hobson, and E. V. Komelsen, The Physical Basis of Ultra High Vacuum, Chapman and Hall, London, 1968. [Pg.379]

The stiffness wouid also be high in the 1-direction and low in the 2-direction, as is easily imagined on the physical basis of the fiber orientation. Imagine that, in the 1-2 plane, the stresses are... [Pg.89]

The reader who is less familiar with the theory of grand partition functions may directly proceed to Eqs. 12a and 13. The physical basis of these formulas and the significance of the quantities CK% will then become apparent in the subsequent paragraph is the vapor pressure (or fugacity) of solute K and y i is the probability of finding a K molecule in a cavity of type i. [Pg.12]

In our analysis, we discuss experimental results of heat transfer obtained by previous investigators and related to incompressible fluid flow in micro-channels of different geometry. The basic characteristics of experimental conditions are given in Table 4.1. The studies considered herein were selected to reveal the physical basis of scale effect on convective heat transfer and are confined mainly to consideration of laminar flows that are important for comparison with conventional theory. [Pg.147]

H. Maskill, In "The Physical Basis of Organic Chemistry" Oxford University Press, pp367-404, Oxford (1985). [Pg.127]

Wolman, Y. in Patai The Chemistry of the Thiol Group, pt. 2 Wiley NY, 1974, p. 677 Maskill, H. The Physical Basis of Organic Chemistry Oxford University Press Oxford, 1985, p. 159. [Pg.358]

A substantial investment in algebra is needed to evaluate the six constants, but the result is remarkable. The exit concentration from an open system is identical to that from a closed system. Equation (9.20), and is thus independent of Dt and Dou The physical basis for this result depends on the concentration profile, a(z), for z<0. When Z) = 0, the concentration is constant at a value if until z = 0+, when it suddenly plunges to u(0+). When D >0, the concentration begins at when z = —oo and gradually declines until it reaches exactly the same concentration, u(0+), at exactly the same location, z = 0+. For z>0, the open and closed systems have the same concentration profile and the same reactor performance. [Pg.333]

Take the limit as and k both approach zero with a hxed ratio between them, jk = Ka- The magnitude of 01- decreases and the functional form changes. Explain the physical basis for these changes. [Pg.377]

The occurrence of a compensation effect can be readily deduced from Eqs. (1.6) and (1.7). The physical basis of the compensation effect is similar to that of the Sabatier volcano curve. When reaction conditions or catalytic reactivity of a surface changes, the surface coverage of the catalyst is modified. This change in surface coverage changes the rate through change in the reaction order of a reaction. [Pg.13]

The physical basis for the Earth s productive natural cycles must not be systematically deteriorated. [Pg.16]

Distillation is a suitable technique for the isolation of volatile organic compounds from liquid samples or the soluble portion of solid samples [24,27-30]. The physical basis of separation depends on the distribution of constituents between the liquid mixture and the vapor in equilibrium with that mixture. The more volatile constituents are concentrated in the vapor phase, which is collected after condensation. The effectiveness of the separation is dependent on the physical properties of the... [Pg.885]

Minerals are well regarded as national assets. Extensive use of mineral resources forms the physical basis of a high standard of living not only in the developed but also in the developing countries. A strong positive correlation exists, for example, between the per... [Pg.39]


See other pages where The Physical Basis is mentioned: [Pg.136]    [Pg.503]    [Pg.1466]    [Pg.2226]    [Pg.135]    [Pg.117]    [Pg.170]    [Pg.32]    [Pg.537]    [Pg.196]    [Pg.430]    [Pg.135]    [Pg.58]    [Pg.59]    [Pg.61]    [Pg.63]    [Pg.65]    [Pg.373]    [Pg.176]    [Pg.486]    [Pg.490]    [Pg.497]    [Pg.537]    [Pg.13]    [Pg.70]    [Pg.551]    [Pg.4]    [Pg.164]    [Pg.266]    [Pg.649]   


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