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Case defined

Experimentally k is normally determined in the limit of zero time, at which time the special case defined by (25) might be expected to hold, since [R2NH2 ] 0 and [BH+] 0. Moreover, k9 > k 9 and k10 > k 10, since usually B and R2NH are probably stronger bases than IV. [Pg.419]

In that case, defining the following four-operators by... [Pg.209]

In his attempts to analyze the early experimental data, Damkohler [55] considered that large-scale, low-intensity turbulence simply distorts the laminar flame while the transport properties remain the same thus, the laminar flame structure would not be affected. Essentially, his concept covered the range of the wrinkled and severely wrinkled flame cases defined earlier. Whereas a planar laminar flame would appear as a simple Bunsen cone, that cone is distorted by turbulence as shown in Fig. 4.43. It is apparent then, that the area of the laminar flame will increase due to a turbulent field. Thus, Damkohler [55] proposed for large-scale, small-intensity turbulence that... [Pg.231]

This deficiency of the theory can be explained as follows The electrically neutral complexes IS and JS do not influence the diffusion potential in the same manner as do the charged complexes, for which the theory works so nicely. In practice, as neither of the two limiting cases defined by Eqs. (13) and (14) will be realistic (compare with the stipulations in Table 6), it seems more sensible to formulate the selectivity constant as follows ... [Pg.132]

Another approach is to develop a global model that contains plausible models as special cases, defined by alternative values of particular parameters. This converts model uncertainty into uncertainty about the model parameters. Again this can be done using either Bayesian or non-Bayesian approaches. This approach is favored by Morgan and Henrion (1990), who describe how it can be applied to uncertainty about dose-response functions (threshold versus nonthreshold, linear versus exponential). [Pg.26]

For these reasons, microbial sensors are less suitable for the determination of individual analytes. However, some practical apphcations for biosensors based on enzymes or antibodies for the specific determination of environmentally relevant compounds can be expected soon [11]. Furthermore, in some cases defined specific metabolic pathways in microorganisms are used, leading to microbial sensors for more selective analysis for those environmental pollutants which cannot be measured by the use of simple enzyme reactions, e.g., aromatic compounds and heavy metals. In this context it is also important to mention the aspect of bio availability, a parameter which is included by the measuring procedure of microbial sensors as an integral effect. [Pg.86]

The equation can be put into nondimensional form, following much the same procedure as used for the wedge case. Define nondimensional variables as... [Pg.222]

In fact, dc0/dt equals the very small value of the difference kpcOL — kpcQ that is virtually zero. It could be decided to neglect this so-cafled source term , but it is much more appropriate to combine eqns. (181a) and (181b) in such a way that (i) the source term is eliminated and (ii) an equation in terms of the total concentration c0t is obtained. To this end, the mean diffusion coefficient is introduced, in this case defined as [11,147]... [Pg.324]

The path of the laser beam and the detector (the ionizer in this case) define a plane perpendicular to the scattering plane in which the source of the molecular beam can be rotated to some scattering angle a. Neutral photofragments are detected through ionization by electron impact. Ions formed in this way can be mass selected in electric and/or magnetic fields. [Pg.275]

Let us find expressions for the matrix elements of these operators for a subshell of equivalent electrons with respect to the relativistic wave functions, in a one-electron case defined by (2.15), and for a subshell, by (9.8). [Pg.232]

The size of the particles that is calculated from these experiments corresponds to particle dimensions plus the double layer thickness, in this case defined by the shear plane inside which the adsorbed species are rigidly held, and outside of which there is free movement. The shear plane can therefore be associated roughly with the outer Helmholtz plane, an approximation often made. The value of the electrostatic potential at the shear plane with respect to the value in bulk solution is called the electrokinetic or zeta potential, 33 (see Section 3.3). [Pg.66]

In view of thermodynamics the ceiling temperature looks like a melting point. Below and above this temperature the system consists of 100% polymer and of 100% monomer, respectively. This is shown in Fig. 20.2. If, however, the polymer is soluble in its monomer, then the free enthalpy of mixing also plays a role and the result will be that the "melting point" is not as sharp as shown there will be a gradual change (i.e. the dashed line) from 100% polymer to 100% monomer. The ceiling temperature is in this case defined as the temperature where the amount of monomer equals the amount of polymer (i.e. at 50%) and equal to (see, e.g. Ivin, 2000) ... [Pg.750]

As expected, we find that the total response function Xa=i Ri = Xa=4 Ri = J2i=1 Ri = 0 (i.e., for each possible time ordering) vanishes exactly in the harmonic case, defined by A = 0 and /x2i 2 = 2 /r10 2. Furthermore, it can be easily seen that in the case of a strict separation of time scales of homogeneous and inhomogeneous broadening, the line shape function becomes g(t) = t/T2 + a212/2 and the total response function reduces exactly to the result obtained within a Bloch picture (see, for example Refs. 52 and 75), e.g.,... [Pg.299]

It is more difficult to interpret changes in average polymerization degrees of LMW and HMW peaks. Fraction of the LMW peak is determined by the proportion of ion pairs among all carbocations. However, if they exchange very rapidly with covalent species, they can not be distinguished from the dormant species and the average DP of the LMW peak is in that case defined by the ratio of the concentrations of reacted monomer to that of covalent species (approximately equal to the concentration of the initiator, provided that initiation is complete). Thus, DP of the LMW peak equals approximately ... [Pg.280]

In practice, it is impossible to obtain medication of 100 % purity, which makes it necessary to check the impurity profile of the dmg. Investigations involve the isolation, identification, and quantification of the impurities, and in many cases define their biological activity and toxicity. Performing such studies is an important part of the development of a dmg and is a part of safe pharmacotherapy. The goal is to prevent tragedies, such as one in 1938 when 105 people died after administration of Elixir Sulfanilamide that was contaminated with diethyl glycol [6]. [Pg.182]

A review of some of the features of these diagrams in terms of the Phase Rule is enlightening (Findlay 1951). A system composed of two different solid forms of a substance will have one component and two solid phases. In the absence of a further definition of the system there will be one degree of freedom. In Fig. 2.7 this is either the temperature or the pressure along the I<->II line. Choosing either variable fixes a point and defines the system. However, suppose that we are interested in the situation when the two phases are in equilibrium with the liquid or the vapour. Each one of those is an additional phase, making three in total and, by virtue of the Phase Rule, rendering the system invariant. Invariance results in a triple point for each case, defined by the intersection of the I<->II curve with the I<->v. and n<->v. curves on the one hand and the intersection of the I<->II curve with the I<->1. and II<->1. curves on the other hand. [Pg.37]

Any of Eqs. [8], [9] and [10] allow the determination of C and also of relevant rate constants in the simplest case defined above. Complications arise, when these rates are time-or polymer yield-dependent. C is seldom time-invariable formation and deactivation of active centers are quite often difficult to express by simple kinetic laws. Nevertheless, the fundamental Eq. [7] should be valid, and Ivanov et al. 35) and Ermakov and Zakharov 6> suggested its modified version applicable to the non-stationary kinetics of polymerization, if only transfer reactions occur. Supposing that kp, ktr, [M], and [X] are time-independent and substituting C by Rp/kp[M], equation ... [Pg.89]

The second type of uncertainty in propositions of the given type results from information deficiency regarding the object x. While the predicate P is in this case defined precisely, information about x is insufficient to determine whether or not x satisfies P. The proposition is in this case either true or false, but its actual truth status cannot be determined. However, it is useful to assign a number in the unit interval [0,1] to the proposition to express the degree of evidence that the proposition is true. Assigning degrees of evidence to relevant propositions is a topic dealt with in measure theory. [Pg.46]

The activity of a drug is very often related to the complementarity of the molecule and the receptor. Such complementarity is in many cases defined in quite a vague manner. This may be demonstrated by a well-... [Pg.228]

Consider a process during the course of which the affinity remains less than a given value A. Now let Aq tend to zero. The limiting case defined in this way is called an equilibrium process or equilibrium transformation. The uncompensated heat of this transformation is zero because of (3.21), and so equation (3.5) reduces to... [Pg.291]

Let us consider two cases defined in Table 1 below In case 1, we obviously have a metastable decomposition into the subsets 1,2 and 3,4 with metastability measure 0.995 while any further decomposition significantly lowers the metastability measure. Table 2 shows that the spectrum of the transfer operator exhibits a corresponding gap after the first two eigenvalues, and that the upper bound from our theorem, (Ai - - A2)/2 = 0.995, is a very good approximation of meta( l, 2, 3,4 ). The second eigenvector t>2 = (0.51,0.49,-0.49,-0.50) clearly exhibits almost constant levels on the two sets 1,2 and 3,4 of the metastable decomposition. In case 2,... [Pg.502]

The above probabilities may be grouped in the matrix given by Eq. 3-17). It should be noted that Eq.(2-18) is not satisfied along each row because the one-step transition probabilities pjk depend on time n. This is known as the non-homogeneous case defined in Eqs.(2-19) and (2-20), due to non-linear rate equations, i.e. Eqs.(3-12). [Pg.196]

From the analysis of the rate laws in Table II one can write plausible mechanisms for the reaction, but always more than one. The chain initiation reaction is in no case defined by the rate law, and the chain carriers cannot be uniquely fixed from the rate law. Therefore no attempt will be made to give mechanisms until further information is available to limit the possibilities. [Pg.170]

Ionization isomerism is another case defined by recognizing that an empirical formula allows some options for the coordination sphere of the metal. It is essentially the same situation as hydrate isomerism, but involves ligands other than water. For example, consider the inert cobalt(III) compound CoBr(S04>5(NH3), which forms two different compounds, one violet, the other red. We know these now as [CoBr(NH3)5](S04) and [Co(NH3)5(S04)]Br, which differ in the choice of which anion occupies the coordination sphere, the other remaining as the counter-ion (Figure 4.25). [Pg.107]


See other pages where Case defined is mentioned: [Pg.2603]    [Pg.150]    [Pg.393]    [Pg.297]    [Pg.411]    [Pg.414]    [Pg.348]    [Pg.91]    [Pg.328]    [Pg.148]    [Pg.113]    [Pg.161]    [Pg.193]    [Pg.390]    [Pg.393]    [Pg.38]    [Pg.274]    [Pg.250]    [Pg.419]    [Pg.450]    [Pg.198]    [Pg.335]    [Pg.702]    [Pg.28]    [Pg.562]   
See also in sourсe #XX -- [ Pg.605 ]




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