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Force defined

It is important to understand that when chemical reactions are involved, this definition of Cl is based ou the driving force defined as the difference between the couceutratiou of un reacted solute gas at the interface and in the bulk of the liquid. A coefficient based ou the total of both uureacted and reached gas could have values. smaller than the physical-absorption mass-transfer coefficient /c . [Pg.620]

Clearly, the maximum degree of simplification of the problem is achieved by using the greatest possible number of fundamentals since each yields a simultaneous equation of its own. In certain problems, force may be used as a fundamental in addition to mass, length, and time, provided that at no stage in the problem is force defined in terms of mass and acceleration. In heat transfer problems, temperature is usually an additional fundamental, and heat can also be used as a fundamental provided it is not defined in terms of mass and temperature and provided that the equivalence of mechanical and thermal energy is not utilised. Considerable experience is needed in the proper use of dimensional analysis, and its application in a number of areas of fluid flow and heat transfer is seen in the relevant chapters of this Volume. [Pg.14]

The functions A are vector potentials of the field, and the

scalar potentials from which the field can be derived through (5) and (9). An infinite number of potentials leading to the same field can be constructed from (6) and (10). Using (5) and (9) the Lorentz force defined in terms of potentials... [Pg.133]

The relationships between rate of cleavage, bond strength and radical-anion redox potential can be combined in one concept. In this, cleavage rate is dependent on a reaction driving force, defined as the difference between the redox potential of the substrate radical-anion and the redox potential of the product anion in equ-librium with the coiresponding radical (E° for bromine ion, bromine radical as an example). [Pg.94]

The standard interpretation of this equation is that the particle is moving on the potential of mean force w q), where q is the reaction coordinate . In a numerical simulation, where the frill interaction potential is V( q, x), (x denotes all the bath degrees of freedom) it is not too difficult to compute the potential of mean force, defined as ... [Pg.3]

Fig. 6.43. The two stages of getting the inner, or < >, potential (a) The work done to bring a unit of positive test charge from infinity to a point just outside the range of the image forces defines the outer, or j/, potential, (b) The charge on the solution is then removed, and the solution is wrapped in an oriented-dipole layer. The work done to transport the test charge across the oriented-dipole layer defines the surface, or, %, potential. Thus, the total work to bring the test charge from infinity to a point just inside the solution is given by s = /s + xs. Fig. 6.43. The two stages of getting the inner, or < >, potential (a) The work done to bring a unit of positive test charge from infinity to a point just outside the range of the image forces defines the outer, or j/, potential, (b) The charge on the solution is then removed, and the solution is wrapped in an oriented-dipole layer. The work done to transport the test charge across the oriented-dipole layer defines the surface, or, %, potential. Thus, the total work to bring the test charge from infinity to a point just inside the solution is given by s = /s + xs.
In a hydrodynamically free system the flow of solution may be induced by the boundary conditions, as for example when a solution is fed forcibly into an electrodialysis (ED) cell. This type of flow is known as forced convection. The flow may also result from the action of the volume force entering the right-hand side of (1.6a). This is the so-called natural convection, either gravitational, if it results from the component defined by (1.6c), or electroconvection, if it results from the action of the electric force defined by (1.6d). In most practical situations the dimensionless Peclet number Pe, defined by (1.11b), is large. Accordingly, we distinguish between the bulk of the fluid where the solute transport is entirely dominated by convection, and the boundary diffusion layer, where the transport is electro-diffusion-dominated. Sometimes, as a crude qualitative model, the diffusion layer is replaced by a motionless unstirred layer (the Nemst film) with electrodiffusion assumed to be the only transport mechanism in it. The thickness of the unstirred layer is evaluated as the Peclet number-dependent thickness of the diffusion boundary layer. [Pg.7]

Isolated Droplet Breakup—in a Velocity Field Much effort has focused on defining the conditions under which an isolated drop will break in a velocity field. The criterion for the largest stable drop size is the ratio of aerodynamic forces to surface-tension forces defined by the Weber number, N (dimensionless). [Pg.92]

The one-dimensional potential curves depicted in Figures 1.1-1.3 represent the dissociation of diatomic molecules for which the potential V(Rab) depends only on the internuclear distance between atoms A and B. However, if one or both constituents are molecules, V is a multidimensional object, a so-called potential energy surface which depends on several (at least three) nuclear coordinates denoted by the vector Q = (Ql,Q2,Q3,---) (Margenau and Kestner 1969 Balint-Kurti 1974 Kuntz 1976 Schaefer III 1979 Kuntz 1979 Truhlar 1981 Salem 1982 Murrell et al. 1984 Hirst 1985 Levine and Bernstein 1987 ch.4 Hirst 1990 ch.3). The intramolecular and intermolecular forces, defined by... [Pg.19]

Throughout the edited volume entitled Principles and Practice of Clinical Research, Gallin (2002a) and contributors adopted the definition of the Association of American Medical Colleges Task Force on Clinical Research. As cited by Gallin (2002b), this task force defined clinical research as ... [Pg.12]

In other words, it is assumed here that the particles are surrounded by a isotropic viscous (not viscoelastic) liquid, and is a friction coefficient of the particle in viscous liquid. The second term represents the elastic force due to the nearest Brownian particles along the chain, and the third term is the direct short-ranged interaction (excluded volume effects, see Section 1.5) between all the Brownian particles. The last term represents the random thermal force defined through multiple interparticle interactions. The hydrodynamic interaction and intramolecular friction forces (internal viscosity or kinetic stiffness), which arise when the macromolecular coil is deformed (see Sections 2.2 and 2.4), are omitted here. [Pg.39]

Note that the condition r>,u — rK(f) — (f M/c2) follows from the definition of p. Quantum conditions further yield r> 2/z. Note the incompatibility between the force defined in Eq. (50) and the energy law defined by the theory of special theory of relativity. One should note here that Einstein, in his studies of the general theory of relativity, started from the force law... [Pg.129]

The phenomenological equations relating the flows and forces defined by Eq. (6.155) are... [Pg.340]

As all the In P vs. x curves were linear within the limit of experimental accuracy, we could not do better than to tit these with the Yukawa force defined by Equation 3.1 and Equation 3.2. We consider first the gradients of the plots, given in Table 3.3. The value of k in the external soaking solution is determined by Equation 3.15... [Pg.52]

I, y, k denotes a circular permutation / Ij, are the molecular moments of inertia and F is an external potential depending on molecular orientation and /(I) white stochastic forces defined by... [Pg.71]

A practical eluotropic series of solvents, based on the expended solubility parameter concept, was reported. This series was defined based on partial specific solubility parameter (5 ) that is equal to the sum of Keeson (5q) and acid-base (2 a b)> which represents the contribution to interaction forces introduced to characterize the solute, the mobile, and the stationary phase in liquid-solid chromatography. Exactly the same two interaction forces define e° and, consequently, there should exist a direct relation between e° and s = o+2 a b- Unfortunately, the general correlation for all the solvents on alumina is poor (r =0.75). [Pg.613]

Chemists have historically employed various means of representating molecular structure. Two-dimensional drawings of atoms connected by lines are some of the most common molecular representations. Each line represents a chemical bond that, in the simplest case, is a pair of electrons shared between the connected atoms, resulting in a very strong attractive interatomic force. The various interatomic forces define the structure or shape of a molecule, while its chemistry is dependent on the distribution of electrons. A chemical reaction involves a change in the electron distribution, i.e., a change in bonding. [Pg.183]


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See also in sourсe #XX -- [ Pg.169 ]

See also in sourсe #XX -- [ Pg.41 ]




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