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Concentrations theorem

The one-to-one correspondence of alloy and host sites is seen explicitly in Eq. (4). For the moment we now concentrate on the transition probability This quantity is proportional to the density of impurities and, according to the optical theorem, is given by... [Pg.469]

Nernst equation for concentration cells, 467 theorem, 484, 489, 508, 531 theory of galvanic cells, 474... [Pg.542]

The average value of the asymmetrical fluctuation is defined as the root mean square (rms) value. Using the Rayleigh theorem,94 the average value of the surface concentration fluctuation, for example, can be written as... [Pg.282]

In fact, since the unsteady-state transport equation for forced convection is linear, it is possible in principle to derive solutions for time-dependent boundary conditions, starting from the available step response solutions, by applying the superposition (Duhamel) theorem. If the applied current density varies with time as i(t), then the local surface concentration at any time c0(x, t) is given by... [Pg.244]

Equation (23) implies that the current density is uniformly distributed at all times. In reality, when the entire electrode has reached the limiting condition, the distribution of current is not uniform this distribution will be determined by the relative thickness of the developing concentration boundary layer along the electrode. To apply the superposition theorem to mass transfer at electrodes with a nonuniform limiting-current distribution, the local current density throughout the approach to the limiting current should be known. [Pg.244]

The effect of external pressure on the rates of liquid phase reactions is normally quite small and, unless one goes to pressures of several hundred atmospheres, the effect is difficult to observe. In terms of the transition state approach to reactions in solution, the equilibrium existing between reactants and activated complexes may be analyzed in terms of Le Chatelier s principle or other theorems of moderation. The concentration of activated complex species (and hence the reaction rate) will be increased by an increase in hydrostatic pressure if the volume of the activated complex is less than the sum of the volumes of the reactant molecules. The rate of reaction will be decreased by an increase in external pressure if the volume of the activated complex molecules is greater than the sum of the volumes of the reactant molecules. For a decrease in external pressure, the opposite would be true. In most cases the rates of liquid phase reactions are enhanced by increased pressure, but there are also many cases where the converse situation prevails. [Pg.219]

In fluorescence spectroscopy, the orientation distribution of the guest probe is not necessarily identical to the actual orientation of the polymer chains, even if it is added at very small concentrations (i.e., a probe with high fluorescence efficiency). As a matter of fact, it is generally assumed that long linear probes are parallel to the polymer main chain, but this is not necessarily the case. Nevertheless, if the relation between the distribution of the probe axes and those of the polymer axes is known, the ODF of the structural units can be calculated from that of the probe thanks to the Legendre s addition theorem. Finally, the added probe seems to be mainly located in the amorphous domains of the polymer [69] so that fluorescence spectroscopy provides information relative to the noncrystalline regions of the polymeric samples. [Pg.324]

It is inappropriate in this survey to attempt to summarise in a short space the results of all the above treatments, but virtually all the calculations indicate that in M(Cp)2 species the 7r(ej) metal-ligand interaction is dominant in the metal to ring bonding. However, debate has largely been concentrated on two points, in the first place the extent of the validity (or otherwise) of Koopmans theorem, and, further, the question of the correct energetic ordering (5 < o < n or o < 5 < n) of the mainly metal tf-type orbitals. [Pg.134]

The fermionic determinant Detiow averaged over instanton anti-instanton positions, orientations and sizes leads to a partition function of light quarks Z. Then the properties of the hadrons and their interactions are concentrated in the QCD effective action written in terms of the quasiparticles. This approach leads to the Diakonov-Petrov(DP) effective action (D.I. Diakonov et.al., 1996). It was shown that DP effective action is a good tool in the chiral limit but fails beyond this limit, checked by the calculations of the axial-anomaly low energy theorems (M.M. Musakhanov et.al., 1997 E. Di Salvo et.al., 1998). [Pg.259]

Another remarkable point is the appearance in [Q(t0)Yfirst time when n = 4 (we cannot have two 6LW) with no particle in common if we do not have at least four particles), but also exist to higher orders in the concentration. Their evaluation necessitates some delicate mathematical manipulations (application of the factorization theorem) but the extension of this technique to the higher-order terms of the virial expansion does not seem to pose any new problem. [Pg.366]

Polymeric chains in the concentrated solutions and melts at molar-volumetric concentration c of the chains more than critical one c = (NaR/) ] are intertwined. As a result, from the author s point of view [3] the chains are squeezed decreasing their conformational volume. Accordingly to the Flory theorem [4] polymeric chains in the melts behave as the single ones with the size R = aN112, which is the root-main quadratic radius in the random walks (RW) Gaussian statistics. [Pg.18]

Because the velocity u contains the random component u, the concentration c is a stochastic function since, by virtue of Eq. (2.2), c is a function of u. The mean value of c, as expressed in Eq. (2.5), is an ensemble mean formed by averaging c over the entire ensemble of identical experiments. Temporal and spatial mean values, by contrast, are obtained by averaging v ues from a single member of the ensemble over a period or area, respectively. The ensemble mean, which we have denoted by the angle brackets ( ), is the easiest to deal with mathematically. Unfortunately, ensemble means are not measurable quantities, although under the conditions of the ergodic theorem they can be related to observable temporal or spatial averages. In Eq. (2.7) the mean concentration (c) represents a true ensemble mean, whereas if we decompose c as... [Pg.216]

The ratio of the mean solution concentration to the feed salt concentration is plotted in Figure 2 as a function of volume flux. Two extreme cases will be of interest. First, when qd/5 - , the right-hand side of Eq, (32) approaches unity. This means that for all values of r, the mean solution concentration becomes the feed salt concentration as the volume flux becomes infinite. The second case is when qd/Dg is very small. In this case Eq. (32) becomes indeterminant. Hence, L Hospltal s Theorem must be applied to find the limiting value. It gives two different... [Pg.259]

Confidence intervals nsing freqnentist and Bayesian approaches have been compared for the normal distribntion with mean p and standard deviation o (Aldenberg and Jaworska 2000). In particnlar, data on species sensitivity to a toxicant was fitted to a normal distribntion to form the species sensitivity distribution (SSD). Fraction affected (FA) and the hazardons concentration (HC), i.e., percentiles and their confidence intervals, were analyzed. Lower and npper confidence limits were developed from t statistics to form 90% 2-sided classical confidence intervals. Bayesian treatment of the uncertainty of p and a of a presupposed normal distribution followed the approach of Box and Tiao (1973, chapter 2, section 2.4). Noninformative prior distributions for the parameters p and o specify the initial state of knowledge. These were constant c and l/o, respectively. Bayes theorem transforms the prior into the posterior distribution by the multiplication of the classic likelihood fnnction of the data and the joint prior distribution of the parameters, in this case p and o (Fignre 5.4). [Pg.83]

Of special interest is that the concentration at the surface, x=0, is almost independent of the concentration in the bulk electrolyte. When the concentration increases by a factor of 500, from 1 to 500mM, the concentration at the surface only increases by a factor of 1.3. This remarkable behavior is the result of the contact value theorem, which for the G-C model takes the form [3] ... [Pg.435]

The experimental verification of Gibbs theorem. Since the osmotic pressure of a solution is generally difficult to measure, it is simplest to choose a case such that Raoult s law holds good and the concentration of the solution may be used in place of osmotic pressure. The solution should therefore be dilute and should be a true solution the solute, that is, must be dispersed as simple molecules and not as molecular aggregates like soap micelles. These conditions were obtained by Donnan and Barker Proc. [Pg.34]


See other pages where Concentrations theorem is mentioned: [Pg.166]    [Pg.166]    [Pg.493]    [Pg.3057]    [Pg.143]    [Pg.119]    [Pg.56]    [Pg.39]    [Pg.133]    [Pg.386]    [Pg.385]    [Pg.950]    [Pg.199]    [Pg.76]    [Pg.11]    [Pg.271]    [Pg.159]    [Pg.442]    [Pg.282]    [Pg.10]    [Pg.24]    [Pg.12]    [Pg.18]    [Pg.453]    [Pg.78]    [Pg.79]    [Pg.86]    [Pg.33]    [Pg.34]    [Pg.36]    [Pg.51]    [Pg.86]   
See also in sourсe #XX -- [ Pg.166 ]




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Theorem of the concentrations in pure mode

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