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Basic Relations

A dimensional analysis with these variables reveals that the functional relations of Eqs. (7.1) and (7.2) must exist  [Pg.131]

The group D npjp is the Reynolds number and sjD is the rouglmess ratio. Three new groups also have arisen which are named [Pg.131]

The hydraulic efficiency is expressed by these coefficients as r,= gHp2/P = C Cg/Cp. [Pg.131]

Although this equation states that the efficiency is independent of the diameter, in practice this is not quite true. An empirical relation is due to Moody [ASCE Trans. 89, 628 (1926)]  [Pg.131]

Geometrically similar pumps are those that have aU the dimensionless groups numerically the same. In such cases, two different sets of operations are related as follows  [Pg.131]

Another dimensionless parameter that is independent of diameter is obtained by eliminating D between CQ and Ch with the result, [Pg.131]

The i(f effect in the kinetics of electrode reactions has been dealt with in a number of important reviews which can be recommended to readers who wish to have further knowledge on this topic (particularly detailed information can be had from the relevant chapters in the monographs by Delahay and Frumkin °° ). [Pg.140]

An ion in the double layer, in particular an ion at a point which is optimum for discharge, is, generally speaking, at a potential different from that in the solution. This potential difference is generally known as the i(f potential. Its existence gives rise to two effects. [Pg.140]

Firstly, the concentrations C, of ions in a respective plane differ from their mean concentrations in the solution (Co). If the surface coverage with discharging particles is small and if the passage of a particle from the bulk to the surface is not accompanied by a substantial change in its standard chemical [Pg.140]

Secondly, the ion is acted upon not by the full metal-solution potential difference , but only by a part of it, viz., cf) - i(f. This means that the value of the true activation energy varies with the potential by a( - [Pg.141]

A similar expression can be easily written for multielectron processes as well as for a reaction in the anodic direction. [Pg.141]


The correlation functions provide an alternate route to the equilibrium properties of classical fluids. In particular, the two-particle correlation fimction of a system with a pairwise additive potential detemrines all of its themiodynamic properties. It also detemrines the compressibility of systems witir even more complex tliree-body and higher-order interactions. The pair correlation fiinctions are easier to approximate than the PFs to which they are related they can also be obtained, in principle, from x-ray or neutron diffraction experiments. This provides a useful perspective of fluid stmcture, and enables Hamiltonian models and approximations for the equilibrium stmcture of fluids and solutions to be tested by direct comparison with the experimentally detennined correlation fiinctions. We discuss the basic relations for the correlation fiinctions in the canonical and grand canonical ensembles before considering applications to model systems. [Pg.465]

The path-integral quantum mechanics relies on the basic relation for the evolution operator of the particle with the time-independent Hamiltonian H x, p) = -i- V(x) [Feynman and... [Pg.39]

By combining Eqs. 4-6 one obtains the basic relation between interface toughness and the force required to break or pull-out a chain... [Pg.229]

In this section, we summarize the fundamental parameters for carbon nanotubes, give the basic relations... [Pg.27]

The body temperature limits for health in terms of internal or core temperature are fairly limited. The limits are basically related to the function of nervous tissue. Body temperatures around 28 °C or less can result in cardiac fibrillation and arrest. Temperatures of 43 °C and greater can result in heat stroke, brain damage, and death. Often, too high a temperature causes irreversible shape changes to the protein molecules of nervous tissue. That is, cooling overheated tissue to normal temperatures may not restore its original function. [Pg.176]

However, if one focuses on the adsorption of a fluid in heterogenous matrices [32,33] and/or on the fluctuations in an adsorbed fluid, it is inevitable to perform developments similar to those above in the grand canonical ensemble. Moreover, this derivation is of importance for the formulation of the virial route to thermodynamics of partially quenched systems. For this purpose, we include only some basic relations of this approach. [Pg.299]

Values of K-equilibrium factors are usually associated with hydrocarbon systems for which most data have been developed. See following paragraph on K-factor charts. For systems of chemical components where such factors are not developed, the basic relation is ... [Pg.4]

The method of Bogart [4] is useful in this case. The basic relation is ... [Pg.56]

The values of a/e determined experimentally by Lobo et al. are indicated [47]. These are the values in the development of the basic relation expressed in Figure 9-21A with correction of i]) suggested by Leva [41]. These a/values were found to correlate a considerable amount of the literature data within 12%. This would mean about a 6% error in tower diameter determined at flooding conditions. [Pg.291]

If the basic relation (Eq. 11.32) is not satisfied for r = 1, we will make the substitution p = rjR, and consider p as an auxiliary basic parameter in which everything is expressed. Solving with respect to rj, we obtain... [Pg.222]

Any equations used must be derived from the basic relation between shear stress ft and shear rate y ... [Pg.832]

The synthesis of poly(organophosphazenes), POPs, is a research area that has involved a lot of effort in the past by many scientists active in the phosphazene domain. There are several important reasons for this, basically related to the high cost of the starting products [44] used to prepare POPs, to difficulties in carefully controlling the reactions involved in the preparative processes [38] and to the need for accurately predicting both molecular weight and molecular weight distribution of the POPs produced [38,45]. [Pg.168]

In fact, considering the basic structure of these materials (vide supra), it can be immediately realized that the basic features of poly(organophosphazenes) are the result of two main contributions. The first one is fixed and is basically related to the intrinsic properties of the -P=N- inorganic backbone, while the second is variable and mostly connected to the chemical and physical characteristics of the phosphorus substituent groups. Skeletal properties in phos-phazene macromolecules intrinsically due to the polymer chain are briefly summarized below. [Pg.183]

The formal thermodynamic analogy existing between an ideal rubber and an ideal gas carries over to the statistical derivation of the force of retraction of stretched rubber, which we undertake in this section. This derivation parallels so closely the statistical-thermodynamic deduction of the pressure of a perfect gas that it seems worth while to set forth the latter briefly here for the purpose of illustrating clearly the subsequent derivation of the basic relations of rubber elasticity theory. [Pg.464]

The basic relations for stndying the properties of the RDMs are the anticommu-tation/commntation relations of gronps of fermion operators since their expectation values give a set of A-representability conditions of the RDMs. Thus,... [Pg.68]

Thns, a plot of reaction rate against adsorption energy of the intermediate species is bell or volcano-shaped and has a distinct maximum. This bell-shaped relation between the rate of a catalytic chemical reaction and the adsorption energy of an intermediate was described first by Aleksei Balandin in the 1930s and is usually associated with his name. This basic relation is preserved in more complex situations when the simplifying assnmptions made above no longer hold. [Pg.524]

Methods and Basic Relations for Relaxation Measurements of Spin-State... [Pg.51]

The analytical models shown result in simple formulas for the heat transfer. These formulas give general insight into the basic relations between different parameters and how important they are for the final result. [Pg.286]

This equation is the basic relation for the mean residence time in a plug flow reactor with arbitrary reaction kinetics. Note that this expression differs from that for the space time (equation 8.2.9) by the inclusion of the term (1 + SAfA) and that this term appears inside the integral sign. The two quantities become identical only when 5a is zero (i.e., the fluid density is constant). The differences between the two characteristic times may be quite substantial, as we will see in Illustration 8.5. Of the two quantities, the reactor... [Pg.268]

Analysis of CSTR Cascades under Nonsteady-State Conditions. In Section 8.3.1.4 the equations relevant to the analysis of the transient behavior of an individual CSTR were developed and discussed. It is relatively simple to extend the most general of these relations to the case of multiple CSTR s in series. For example, equations 8.3.15 to 8.3.21 may all be applied to any individual reactor in the cascade of stirred tank reactors, and these relations may be used to analyze the cascade in stepwise fashion. The difference in the analysis for the cascade, however, arises from the fact that more of the terms in the basic relations are likely to be time variant when applied to reactors beyond the first. For example, even though the feed to the first reactor may be time invariant during a period of nonsteady-state behavior in the cascade, the feed to the second reactor will vary with time as the first reactor strives to reach its steady-state condition. Similar considerations apply further downstream. However, since there is no effect of variations downstream on the performance of upstream CSTR s, one may start at the reactor where the disturbance is introduced and work downstream from that point. In our generalized notation, equation 8.3.20 becomes... [Pg.295]

Equations. For a ID two-phase structure Porod s law is easily deduced. Then the corresponding relations for 2D- and 3D-structures follow from the result. The ID structure is of practical relevance in the study of fibers [16,139], because it reflects size and correlation of domains in fiber direction . Therefore this basic relation is presented here. Let er be50 the direction of interest (e.g., the fiber direction), then the linear series expansion of the slice r7(r)]er of the corresponding correlation function is considered. After double derivation the ID Fourier transform converts the slice into a projection / Cr of the scattering intensity and Porod s law... [Pg.137]

We have chosen Gaussian thickness distributions, because structure visualization by means of IDF or CDF exhibits thickness distributions that frequently look very similar to Gaussians97. The presented relations for the ID intensity and the IDF are the basic relations for many ID structure models, comprising the general analysis of materials made from layers, highly oriented microfibrillar materials, and the direction-dependent analysis of anisotropic materials. [Pg.180]

The second comment is that we have chosen the most prevalent elementary processes (unimolecular and bimolecular reactions) to illustrate how to relate thermochemical with kinetic data. Different molecularities will naturally change many equations just presented, but the basic relations 3.8 and 3.9 will not be affected. [Pg.42]

Equation 7.8 may be regarded as the basic relation between —AP, V, and /. Two important types of operation are (i) where the pressure difference is maintained constant and (ii) where the rate of filtration is maintained constant. [Pg.376]

Schnell, G. Thiemig, K. Magnets Basic Relations, Engineering, Applications , Munich, 1973. [Pg.468]

Modelization of the System. Theoretical treatment of polyfunctional monomers condensation polymerization has been firstly proposed by Flory and Stockmayer (22.23 and later by Gordon, Bruneau, Macosko and others (24-26. These theories lay out the basic relation between extent of reaction and average molecular weight of the resulting non linear polymers. [Pg.83]

Finally we mention some basic relations which are essential in the discussion of explicitly orbital dependent functionals. Examples of such functionals are the Kohn-Sham kinetic energy and the exchange energy which are dependent on the density due to the fact that the Kohn-Sham orbitals are uniquely determined by the density. The functional dependence of the Kohn-Sham orbitals on the density is not explicitly known. However one can still obtain the functional derivative of orbital dependent functionals as a solution to an integral equation. Suppose we have an explicit orbital dependent approximation for in terms of the Kohn-Sham orbitals then... [Pg.114]

Recalling the basic relation obtained by taking the expectation value of the anticommutator of two fermion operators ... [Pg.42]


See other pages where Basic Relations is mentioned: [Pg.95]    [Pg.167]    [Pg.171]    [Pg.446]    [Pg.274]    [Pg.95]    [Pg.140]    [Pg.432]    [Pg.518]    [Pg.190]    [Pg.7]    [Pg.172]    [Pg.35]    [Pg.173]    [Pg.474]    [Pg.136]    [Pg.103]    [Pg.130]    [Pg.162]    [Pg.310]    [Pg.358]    [Pg.75]   


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