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Extreme concentrations

This equation has limits at extreme concentrations that are useful expressions. When 1 n[A2]. the rate approximates a first-order equation, with a rate constant of 2k, in that limit the rate is independent of [BJ. The other limit is realized when 1 [Pg.82]

FIGURE 4.4 Extreme concentrations, a ix and aout within a loop reactor. The case shown is for kt — 3. [Pg.142]

In the application of the previous chemical methods, a certain amount of steady-state continuity has been built into the system. To accomplish this, initial concentrated alkaline and acid rinse wastewaters are retained after dumping in the waste holding tank [T-91] (Figure 6.4) and acid chromium plating wastewater is stored in the waste holding tank [T-51], Extremely concentrated chromium plating wastewater from rinse step No. 1 is sent to an evaporation tank [T-40] for... [Pg.246]

The expression given for X as a function of C leaves us in trouble at both ends of the diffusion profile. X appropriately tends towards + oo and - oo when CCe tends asymptotically towards —0.05 and 1.93, respectively, which are nearly the extreme concentrations in the profile. This is what we expect from an infinite system. However, the integrals of the rational fractions are simply natural logarithms which cannot be evaluated for a zero argument and therefore do not converge when evaluated between C0 and Cl. We will therefore restrict the calculation to the interval between extreme concentrations, say C0 = 1.865 and = 0.012. The flux at both ends will not be strictly zero, since for these values,... [Pg.427]

The kidneys are extremely well-perfused organs, with about 1500 L of blood flowing through them every day. Approximately 180 L of primary urine is filtered out of this. Removal of water leads to extreme concentration of the primary urine (to approximately one-hundredth of the initial volume). As a result, only a volume of 0.5-2.0 L of final urine is excreted per day. [Pg.322]

Continued nebuiization Continued nebulization of acetylcysteine with a dry gas results in concentration of drug in the nebulizer due to evaporation. Extreme concentration may impede nebulization and drug delivery. Dilute with Sterile Water for Injection as concentration occurs. [Pg.758]

Regarding compressed emulsions, however, the above analysis cannot be applied since the droplets are distorted by the compressive force into complex, irregular shapes. Variables such as the area of the film between adjacent droplets and the disjoining pressure become extremely difficult to calculate. Nevertheless, calculations can be performed for the particular case of compressed, extremely concentrated systems, where <)> approaches unity. This is because, as - 1, the droplets more or less resemble the polyhedron of the unit cell. [Pg.171]

Apart from sodium hypochlorite and sodium bromide solutions, almost all other liquid biocides (or biocide intermediates) are nonoxidizer types. Most nonoxidizers are manufactured by specialist chemical companies, who sell these branded products for scores of different sanitizing or disinfection applications, of which cooling water system treatment is only one. These chemicals may be merely renamed (according to subregistration permits) or they may be blended with other biocides or inhibitors to form new and different products with accordingly modified properties. Some biocides may only be available from the primary manufacturer, often as extremely concentrated and hazardous materials. These chemicals will then usually require some form of dilution, stabilization, and quality verification before being incorporated into a service company s product line. [Pg.183]

Salts of Strong Acids/Bases 241 Salts of Weak Acids 242 Salts of Weak Bases 244 Extreme Concentrations 245 Other Acidic Species 247 Buffers 248... [Pg.437]

The production of botrytized wines is initially limited by the special conditions required for noble rot development. Noble rot develops concurrent with berry dehydration. In the process, compounds present in the overripe grapes and produced by B. drierea become extremely concentrated. The result is the generation of wines with very high sugar and extract contents, and exceptional aroma richness. [Pg.196]

The objective function (7) in accordance with the general purpose of MEIS that was mentioned in the introduction, i.e., finding the state with extreme value of the system property of interest to a researcher, in this case determines the extreme concentration of the given set of substances. Equality (8) represents a material balance. Expression (9) represents the region of thermodynamic attainability from point y. It is obvious that in Dt(y) the inequalities are satisfied G(xeq) < G(x) < G(y), where xeq—the final equilibrium point. Inequalities (10) are used to set the constraints on macroscopic, including irreversible, kinetics. Presence of this constraint makes up principal difference of the model (7)-( 12) from previous modifications of parametric MEISs. The choice of equations for the calculation of individual terms under the sign of sum in the right-hand side of equality (11) depends on the properties of the considered system. [Pg.18]

Model (29)-(34) determines the chemical process mechanism which is optimal from the stand point of the formation of a sought extreme concentration of the given set of substances (Scpy) that are ranked in terms of... [Pg.25]

The systems discussed below are restricted to ones in which the penetrant1 is a solvent or a "plasticizer for a given polymer and in which its concentration is sufficiently small in comparison with the concentration of polymer. Such systems may be referred to as extremely concentrated solutions of polymer. With this restriction we shall not treat here diffusion processes of gaseous substances, such as oxygen and carbon dioxide. [Pg.2]

Another obstacle to effective using of antioxidants is their extreme concentration-effect dependence. As noted above, antioxidants applied in high concentrations produce an opposite effect and do not inhibit but accelerate free radical reactions. The phenomenon may be attributed either to a high activity of radicals accumulated from inhibitors or to the prevailing consumption of natural antioxidants as compared with synthetic ones introduced. Many of these effects depend on the initial characteristics of free radical processes and the initial level of antioxidants. [Pg.6]

The insertion with CpFe(CO)2R in organic solvents follows second-order kinetics, first order in both the alkyl complex and the SO2. However, the rate profile, i.e., R = i-Pr > CH2CMe3 > Me 71, 77), is not that expected for a backside approach of SO2. Such an attack would be suggested by the observation of inversion at a carbon in the insertion with CpFe(CO)2CHDCHDCMe3 in various solvents 13S). However, this stereochemical result cannot be unambiguously applied to the mechanistic problem in question because extremely concentrated SO2 solutions were employed. A similar difficulty exists with the insertion... [Pg.49]

A further very interesting feature of this reaction system is that the apparent activation energy for the over-all reaction [Eq. (XIII.18.2)] is close to 30 Real when (O2) (O3), while in almost pure O3 the initial rate becomes independent of O2 and the apparent activation energy now appears to be about 24 Real. These two extreme concentration regions are characterized also by the fact that O2 acts as an accelerator in concentrated O3 and an inhibitor in dilute O3. In addition, wall recombination of O atoms can be shown to accelerate the rate in dilute O3 and inhibit the rate in concentrated... [Pg.405]

An experiment that correlates spin-conpled carbons. A very insensitive experiment that can be made practical if the sample can be C enriched. At natural abundance extremely concentrated samples and long acquisition times are reqnired however, direct carbon-carbon connectivity can be obtained. [Pg.208]


See other pages where Extreme concentrations is mentioned: [Pg.182]    [Pg.77]    [Pg.110]    [Pg.287]    [Pg.152]    [Pg.591]    [Pg.280]    [Pg.14]    [Pg.140]    [Pg.276]    [Pg.192]    [Pg.107]    [Pg.281]    [Pg.307]    [Pg.182]    [Pg.209]    [Pg.246]    [Pg.150]    [Pg.22]    [Pg.68]    [Pg.245]    [Pg.148]    [Pg.307]    [Pg.18]    [Pg.151]    [Pg.303]    [Pg.2]    [Pg.67]    [Pg.280]    [Pg.103]    [Pg.149]   
See also in sourсe #XX -- [ Pg.245 , Pg.246 ]




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