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Interpretation of the limits

The simplest possible reaction mechanism likely to take the experimental observations relative to the first limit into account, is the following.  [Pg.184]

This mechanism includes an initiation (103), propagation reactions (104) to (106) and linear termination reactions at the reactor walls (107) and (108). The propagation reactions (104) and (106) are branching reactions, as they multiply the number of free radicals by 2 each time they occur. The HC radical does not play a kinetic role, which means that it is not very reactive, and its chemical role is minor, if the long chain approximation is assumed, which is the same as saying that the reactants are consumed and the products formed essentially by the reactions (104) to (106). [Pg.185]

In order to be able to calculate the kinetic laws from the mechanism, as well as using the LCA, the hypothesis that the 0 and OH free radicals are much more reactive than the H ones will be made. The following quasi-stationary equations are deduced  [Pg.185]

Reaction (107) occurs on the surface S of the reactor walls, whereas the balance is carried out for the volume V of the gaseous phase, which necessitates introducing the SA ratio. [Pg.185]

The integration of the equation (113), assuming that the concentrations of H2 and O2 are constant, gives the following relationship  [Pg.185]


Unfortunately, little direct information is available on the physicochemical properties of the interface, since real interfacial properties (dielectric constant, viscosity, density, charge distribution) are difficult to measure, and the interpretation of the limited results so far available on systems relevant to solvent extraction are open to discussion. Interfacial tension measurements are, in this respect, an exception and can be easily performed by several standard physicochemical techniques. Specialized treatises on surface chemistry provide an exhaustive description of the interfacial phenomena [10,11]. The interfacial tension, y, is defined as that force per unit length that is required to increase the contact surface of two immiscible liquids by 1 cm. Its units, in the CGS system, are dyne per centimeter (dyne cm" ). Adsorption of extractant molecules at the interface lowers the interfacial tension and makes it easier to disperse one phase into the other. [Pg.224]

Statistical Interpretation of the Limiting Laws of Very Dilute Solutions. [Pg.319]

These measurements are affected by temperature and relative humidity (RH), so the conditions of measurement will affect the interpretation of the limits defined earlier. The measurements should be considered accurate to within a factor of 2. [Pg.75]

Considerable attention has been given to the molecular interpretation of the limiting anisotropies (rj). The impetus for the analysis arises ffom a desire to understand the properties of the membranes that are responsible for the hind ed rotation. In one analysis,the rodlike DPH molecule is assumed to exist in a square-well potential such that its rotation is unhindered until acertain angle (Qc) is reached Rotation beyond this angle is as imed to be... [Pg.332]

The molecular origin of the unusual properties of bimodal PDMS networks having been elucidated at least to some extent, it is now possible to utilize these materials in a variety of applications. The first involves the interpretation of the limited chain extensibility in terms of the configurational characteristics of the PDMS chains making up the network structure [6-8]. [Pg.40]

The engineering rules for detail design are not particularly difficult or complicated except in the area of interpretation of the limitations on SILs. It is easy to develop the design details but the designer must be aware at all times of the context of the work, input from the SRS, output to satisfy the validation phase. The quality assurance environment is the key to success. [Pg.243]

Expansion of the bound-mode fields 32-2 Governing equations for the field expansions 32-3 Physical interpretation of the limit A - 0 32-4 Propagation constants... [Pg.623]

Once the anharmonicity of the potential as a possible source for the fifth-order Raman signal was taken into account, some modifications were made to the MMBO model. In the simplest case the anharmonicity was introduced as a perturbation to the harmonic vibrational modes (see (1.9)) [31]. This model proved to have the same convenience in interpretation of the limiting cases as the simple MMBO model but with the added possibility of distinction between signal generated by the nonlinearity in the polarizability as opposed to signal generated by the anharmonicity. [Pg.14]

Any interpretation of the Type I isotherm must account for the fact that the uptake does not increase continuously as in the Type II isotherm, but comes to a limiting value manifested in the plateau BC (Fig. 4.1). According to the earlier, classical view, this limit exists because the pores are so narrow that they cannot accommodate more than a single molecular layer on their walls the plateau thus corresponds to the completion of the monolayer. The shape of the isotherm was explained in terms of the Langmuir model, even though this had initially been set up for an open surface, i.e. a non-porous solid. The Type I isotherm was therefore assumed to conform to the Langmuir equation already referred to, viz. [Pg.197]

The disputes that followed these events centered around interpretation of the 1938 act, which states that "The Secretary shall promulgate regulations providing for the listing of coal-tar colors which are harmless and suitable for use in food..." The FDA felt that harmless meant that a colorant must be safe regardless of the amount used, that is, harmless per se and on this basis deHsted the colorants in question. The food-color manufacturers argued that the FDA interpretation of the law was too strict, that a color additive need only be harmless when properly used, and that the FDA should estabHsh safe limits. They also contended that the conditions used for the new animal feeding tests were too severe. [Pg.432]

The amplitudes and the phases of the diffraction data from the protein crystals are used to calculate an electron-density map of the repeating unit of the crystal. This map then has to be interpreted as a polypeptide chain with a particular amino acid sequence. The interpretation of the electron-density map is complicated by several limitations of the data. First of all, the map itself contains errors, mainly due to errors in the phase angles. In addition, the quality of the map depends on the resolution of the diffraction data, which in turn depends on how well-ordered the crystals are. This directly influences the image that can be produced. The resolution is measured in A... [Pg.381]

Guide to the application and interpretation of the model water byelaws (1986 Edition), Ellis Harwood Limited, Publishers, Byelaw 52, 120. [Pg.362]

This detailed interpretation of the mass spectrum in Figure 7 in terms of structure 10 is included to illustrate the advantages and limitations... [Pg.232]

Overall, the RDE provides an efficient and reproducible mass transport and hence the analytical measurement can be made with high sensitivity and precision. Such well-defined behavior greatly simplifies the interpretation of the measurement. The convective nature of the electrode results also in very short response tunes. The detection limits can be lowered via periodic changes in the rotation speed and isolation of small mass transport-dependent currents from simultaneously flowing surface-controlled background currents. Sinusoidal or square-wave modulations of the rotation speed are particularly attractive for this task. The rotation-speed dependence of the limiting current (equation 4-5) can also be used for calculating the diffusion coefficient or the surface area. Further details on the RDE can be found in Adam s book (17). [Pg.113]

The uncertainties associated with the data base of an individual river basin are compounded when the intent is to provide a global perspective. This point is made in a recent bound volume of UNEP data in which a number of data interpretation limitations are sited. Quality of data varies from one individual reporting entity to another and the precision of the data is usually not possible to ascertain. Thus direct comparisons between data from one country, or even one laboratory to the next are not always possible. Since uncertainties associated with the data (variability, accuracy, precision, etc.) are often not specified, the significance of the data may be difficult to determine and no valid interpretation of the data may therefore be possible. It comes as no surprise that these and similar data from other data bases are often, if not usually, inadequate to establish cause and effect relationships. [Pg.244]


See other pages where Interpretation of the limits is mentioned: [Pg.228]    [Pg.27]    [Pg.74]    [Pg.55]    [Pg.228]    [Pg.58]    [Pg.69]    [Pg.184]    [Pg.16]    [Pg.627]    [Pg.104]    [Pg.228]    [Pg.27]    [Pg.74]    [Pg.55]    [Pg.228]    [Pg.58]    [Pg.69]    [Pg.184]    [Pg.16]    [Pg.627]    [Pg.104]    [Pg.1645]    [Pg.2072]    [Pg.2123]    [Pg.71]    [Pg.410]    [Pg.93]    [Pg.3]    [Pg.96]    [Pg.346]    [Pg.332]    [Pg.805]    [Pg.85]    [Pg.199]    [Pg.130]    [Pg.152]    [Pg.160]    [Pg.251]    [Pg.193]    [Pg.236]    [Pg.100]   


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