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** Discussion and Comparison of Particular Cases **

** Particular case where the sub-system is itself monovariant **

** Particular risk analysis case studies **

The concentration gradient parallel to the surface is only important for small electrodes and low volume flow rates, as will be discussed later. [Pg.384]

There have been a number of approaches to the study of transport across a wall bounding a pulsating flow. The response of the limiting current density, i im, at a tubular electrode in the presence of pulsations was obtained numerically by Mizushina et al. [20, 21] and confirmed analytically by Patel etal. [22]. By invoking the L6v que approximation [8, 9], equation (10.13) [Pg.384]

If the electrode were partially blocked, or behaved as an array of UMEs, then the characteristic length for the scaling would be different and would depend upon whether the concentration boundary layers for the different active areas interacted. If the electrode could be represented as consisting of two or more independent active areas, then two or more characteristic relaxations would be observed in the response, and the length scale could be deduced from the dependence of the measured H values on Re. Addi- [Pg.386]

The derivation leading to equation (10.14) assumes that mass transport to the electrode by diffusion occurs only normal to the surface. This is not true at the edge of the electrode, where axial diffusional rates can be quite high. The effect becomes increasingly evident when the electrode behaviour is dominated by the edges. For a channel microband electrode this is evident with short length electrodes and low solution velocities [23-25]. For an UME (i.e., an electrode where at least one dimension is comparable to 5D) implanted in the wall of a flow channel, when the [Pg.387]

In order to reply to some particular cases of NDT such that the detection two close defects and the fine thickness measure, we have developed techniques adapted to this type of problem. [Pg.225]

If the desorption rate is second-order, as is often the case for hydrogen on a metal surface, so that appears in Eq. XVIII-1, an equation analogous to Eq. XVIII-3 can be derived by the Redhead procedure. Derive this equation. In a particular case, H2 on Cu3Pt(III) surface, A was taken to be 1 x 10 cm /atom, the maximum desorption rate was at 225 K, 6 at the maximum was 0.5. Monolayer coverage was 4.2 x 10 atoms/cm, and = 5.5 K/sec. Calculate the desorption enthalpy (from Ref. 110). [Pg.739]

three-atom system, the allyl radical. A two anchor loop applies in this case as illush ated in Figure 12 The phase change takes place at the allyl anchor, and the phase-inverting coordinate is the asymmetric stretch C3 mode of the allyl radical. Quantum chemical calculations confiiin this qualitative view [24,56]. In this particular case only one photochemical product is expected. [Pg.349]

The SAso = 0 limits of the fomiulas presented in this subsection cover all particular cases (including Uj = 1, Oc = l,anduj = 2, Uc = 1) handled in the previous works [18,132,153]. [Pg.538]

Asymmetry in a similarity measure is the result of asymmetrical weighing of a dissimilarity component - multiplication is commutative by definition, difference is not. By weighing a and h, one obtains asymmetric similarity measures, including the Tversky similarity measure c j aa 4- fih + c), where a and fi are user-defined constants. The Tversky measure can be regarded as a generalization of the Tanimoto and Dice similarity measures like them, it does not consider the absence matches d. A particular case is c(a + c), which measures the number of common features relative to all the features present in A, and gives zero weight to h. [Pg.308]

Algebraically, the dusty gas flux relations are identical with one of the many particular cases of the Feng and Stewart model, as we shall see. However, the two differ conceptually in their approach to deriving the flux i elations. ... [Pg.63]

Without assuming something specific about the reaction rate, it is not possible to go further and actually determine the micropore fluxes. We shall therefore consider the particular case of a first order reversible isomeri-... [Pg.82]

As a particular case of this result, it follows that the stoichiometric relations are always satisfied in a binary mixture at the limit of bulk diffusion control and Infinite permeability (at least to the extent that the dusty gas equations are valid), since then all the binary pair bulk diffusion coefficients are necessarily equal, as there is only one of them. This special case was discussed by Hite and Jackson [77], and the reasoning set out here is a straightforward generalization of their treatment. [Pg.149]

Ihese relative probabilities can be easily determined by simply counting the number c imes during the simulation that the relevant value of lambda reaches unity. In the case ( the para-substituted benzamidines it was possible after only a relatively short simulatio (110 po) to observe that the p-chloro and p-methyl derivatives were significantly weaki than the p-amino and the parent compound (Figure 11.18). In this particular case, all foe... [Pg.603]

Discriminant emalysis is a supervised learning technique which uses classified dependent data. Here, the dependent data (y values) are not on a continuous scale but are divided into distinct classes. There are often just two classes (e.g. active/inactive soluble/not soluble yes/no), but more than two is also possible (e.g. high/medium/low 1/2/3/4). The simplest situation involves two variables and two classes, and the aim is to find a straight line that best separates the data into its classes (Figure 12.37). With more than two variables, the line becomes a hyperplane in the multidimensional variable space. Discriminant analysis is characterised by a discriminant function, which in the particular case of hnear discriminant analysis (the most popular variant) is written as a linear combination of the independent variables ... [Pg.719]

Note that this is only a particular case of Williamson s general method for the preparation of ethers. [Pg.218]

In this particular case, the calculations are completely symmetrical up to Eqs. (8-30). Evei ything we have said for a we can also say for p. At self-consistency, a = p so we can substitute a for p at any point in the iterative process, knowing that as we approach self-consistency for one, we approach the same self-consistent value for the other. [Pg.239]

In this particular case, the equilibrium average is taken over the initial rotational states whose probabilities are denoted pir, any initial vibrational states that may be populated, with probabilities piv, and any populated electronic states, with probabilities pig. [Pg.423]

As stated above, the CG coefficients can be worked out for any particular case using the raising and lowering operator techniques demonstrated above. Alternatively, as also stated above, the CG coefficients are tabulated (see, for example, Zare s book on angular momentum the reference to which is given earlier in this Appendix) for several values of j, j, and J. [Pg.629]

The 3—21G basis is an exception to the notation above. In this particular case, the d functions are added only to 2nd row atoms, A1 through Ar. In order to indicate this difference, this basis is sometimes given the notation 3—21G( ). [Pg.81]

Semiempirical, DFT, and ah initio methods also work well. Correlation effects are sometimes included for the sake of increased accuracy, but are not always necessary. One particular case for which correlation is often necessary is fluorine compounds. [Pg.285]

For electrophilic substitutions in general, some form of the S 2 mechanism is now believed to operate. We can now review the evidence concerning the particular case of nitration. [Pg.108]

If, on the other hand, the encounter pair were an oriented structure, positional selectivity could be retained for a different reason and in a different quantitative sense. Thus, a monosubstituted benzene derivative in which the substituent was sufficiently powerfully activating would react with the electrophile to give three different encounter pairs two of these would more readily proceed to the substitution products than to the starting materials, whilst the third might more readily break up than go to products. In the limit the first two would be giving substitution at the encounter rate and, in the absence of steric effects, products in the statistical ratio whilst the third would not. If we consider particular cases, there is nothing in the rather inadequate data available to discourage the view that, for example, in the cases of toluene or phenol, which in sulphuric acid are nitrated at or near the encounter rate, the... [Pg.119]

The cleanup of this oil is exactly like that which was done in Method 1. The oil is dissolved in about SOOmL of 3N HCl and the solution extracted with TOOmL of DCM. The chemist remembers that in this particular case the MDMA or meth is going to stay in the HCl/water but that unreacted, valuable MD-P2P or P2P is going to be in that DCM so it, of course, is saved. The HCl/MDMA solution is then basified with concentrated NaOH so that at around pH 9 the happy little beads of final, freebase product will appear in the solution. As usual, the oil is extracted with DCM, dried through Na2S04 and the DCM removed by distillation. The final product here is usually a little darker in color than the product achieved in Method 1, but it is still remarkably clean and may be crystallized as is with the crystallization process removing most of the color impurities. Of course the chemist may wish to vacuum distill to afford clear product. The average yield with this method is 60-70%. [Pg.103]

Note for highly substituted allenes containing silicon, gernanium or tin we observed deviations of the calculated chemical shifts from the measured values, and one should therefore treat these particular cases with special care. [Pg.256]

Figure 7.21 illustrates a particular case where the maximum of the v = 4 wave function near to the classical turning point is vertically above that of the v" = 0 wave function. The maximum contribution to the vibrational overlap integral is indicated by the solid line, but appreciable contributions extend to values of r within the dashed lines. Clearly, overlap integrals for A close to four are also appreciable and give an intensity distribution in the v" = 0 progression like that in Figure 7.22(b). [Pg.248]

An additional regularity of the solution near the point xi takes place in some particular cases. For example, assume that the solution u satisfies the condition [u] =0 on B i n S , where B i is a ball centered at xi. Using the technique of Section 2.5, we can prove that the equation —Au = f holds in Bx, and consequently, u G Hf Bx,). In this case all the integrals in (4.98) make sense. Consequently, by (4.62), (4.93), the equality (4.97) follows. [Pg.270]

In this section we shall prove the existence of a solution of the elastoplastic boundary value problem for the particular case of a nonsmooth boundary which arises if we remove a two-dimensional surface from the interior of the body. [Pg.301]

Cases can be classified as either hermetic or nonhermetic, based on their permeabiUty to moisture. Ceramics and metals are usually used for hermetic cases, whereas plastic materials are used for nonhermetic appHcations. Cases should have good electrical insulation properties. The coefficient of thermal expansion of a particular case should closely match those of the substrate, die, and sealing materials to avoid excessive residual stresses and fatigue damage under thermal cycling loads. Moreover, since cases must provide a path for heat dissipation, high thermal conductivity is also desirable. [Pg.530]

Mechanical Properties. Properties of typical grades of PBT, either as unfiUed neat resin, glass-fiber fiUed, and FR-grades, are set out in Table 8. This table also includes impact-modified grades which incorporate dispersions of elastomeric particles inside the semicrystalHne polyester matrix. These dispersions act as effective toughening agents which greatly improve impact properties. The mechanisms are not fiiUy understood in all cases. The subject has been discussed in detail (171) and the particular case of impact-modified polyesters such as PBT has also been discussed (172,173). [Pg.300]

Recent air pollution regulations limit the amount of volatile organic carbon (VOC) that can be discharged from wastewater treatment plants. Benzene is a particular case in which air emission controls are required if the concentration of benzene in the influent wastewater exceeds 10 mg/L. [Pg.223]

Electrodes. AH of the finished silver electrodes have certain common characteristics the grids or substrates used in the electrodes are exclusively made of silver, although in some particular cases silver-plated copper is used. Material can be in the form of expanded silver sheet, silver wire mesh, or perforated silver sheet. In any case, the intent is to provide electronic contact of the external circuit of the battery or cell and the active material of the positive plate. Silver is necessary to avoid any possible oxidation at this junction and the increased resistance that would result. [Pg.554]

** Discussion and Comparison of Particular Cases **

** Particular case where the sub-system is itself monovariant **

** Particular risk analysis case studies **

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