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Equation quantitative information

One of tlie limitations of dimensional similitude is tliat it shows no dueet quantitative information on tlie detailed meehanisms of the various rate proeesses. Employing the basie laws of physieal and eheiTtieal rate proeesses to matliematieally deseiibe tlie operation of tlie system ean avert this shorteoiTung. The resulting matliematieal model eonsists of a set of differential equations tliat are too eomplex to solve by analytieal metliods. Instead, numerieal methods using a eomputerized simulation model ean readily be used to obtain a solution of tlie matliematieal model. [Pg.1044]

Quantitative information can be drawn from such plots. For the a-th order kinetics the slope is the reaction order a and the intercept is In k. For the catalytic reaction considered above with the surface reaction as the rate-limiting process, linearization of the rate equation (5.4-112) leads to ... [Pg.314]

As far as we know, the literature contains no quantitative information on the solubility of carbocation salts and the qualitative information available indicated that such salts are relatively insoluble in the solvents of interest. Our first problem was to predict how changes in the structure of the salt would affect the solubility. Although the ideal solubility equation [Equation (1)] cannot be applied rigorously to ionic solutes, our first step was to examine its utility. [Pg.191]

Also when resorting to heuristic rate equations or other approximative schemes, the construction of detailed kinetic models necessitates quantitative knowledge about the kinetic properties of the involved enzymes and membrane transporters. Notwithstanding the formidable progress in experimental accessibility of system variables, detailed in Sections IV and VI, for most metabolic systems such quantitative information is only scarcely available. [Pg.188]

In theory, to describe a XANES spectrum is not an easy task. The equations discussed earlier in this chapter for EXAFS are not valid at low k-values (i.e., energies close to that of the edge), and instead the X-ray absorption will have to be calculated from first principles, which is a specialism in itself. Fortunately, XANES spectra can usually be very well interpreted with the help of reference spectra of known compounds, and constructing linear combinations of references to fit the spectrum of the catalyst often works well to obtain quantitative information on composition. [Pg.173]

One of the limitations of dimensional similitude is that it shows no direct quantitative information on the detailed mechanisms of the various rate processes. Employing the basic laws of physical and chemical rate processes to mathematically describe the operation of the system can avert this shortcoming. The resulting mathematical model consists of a set of differential equations that are too complex to solve by analytical methods. Instead, numerical methods using a computerized simulation model can readily be used to obtain a solution of the mathematical model. [Pg.1044]

Here, kd is the inverse of the Debye length. Even though the -potentials for latex spheres may exceed 25 mV and, therefore, require a more complex equation to relate to mobility (as per O Brien and White [265]), the low ionic strength (small kd) of El-FFF measurements should still ensure a proportionality between pe and . From the retention data, it is possible to obtain quantitative information regarding either the -potential of samples with known particle size eluting from the channel or the particle size, if the electrophoretic mobility is known. [Pg.126]

Equation (23) shows that the measured parameter, X3, is a linear function of the concentrations of the solutes. This is similar to what one has with, e.g., spectrophotometry. In PALS however there is no such means as to change the excitation wavelength to enrich information deriving reliable stability constants through PAT requires the study of a large number of solute concentrations. Quantitative information is difficult to obtain when too many equilibria are present [110]. [Pg.105]

It follows, then, that when a solution of Hg2+ ion is treated with an equimolar (or greater) quantity of Hg, a solution of Hg2+ is formed. This conclusion, as well as the accuracy of all the quantitative information in all of the above equations assume that we are dealing with uncomplexed aqua ions. This, of course, is seldom the case. [Pg.602]

The conformational assignments may be applied in the same way to the pXr+ values of benzhydrols, but unfortunately no quantitative information was obtained because of limited substituent data in the respective Y sets. The substituent effects on the solvolyses of benzhydryl chlorides (Table 13) are treated even more precisely with equation (2) than those on the pXr values and they can be interpreted in the same way based on the conformational assignment. [Pg.341]

The balanced equation represents a chemical reaction. It not only identifies the reactants and the products, but also gives quantitative information on the ratios of all substances involved in the reaction (Section 8.1). [Pg.246]

Under elevated pressures, the rocksalt stmcture transforms into the CsCl structure. Changes in lattice constants and measurements of other physical properties have provided much quantitative information for empirical fits to equations of state. Modem theoretical tools are used for obtaining a deeper understanding of charge being transferred back from the anion towards the cation in the aUcah hahdes. However, as can be seen from calculations of their cohesive properties, even nowadays there are problems to be solved for such simple stmctures. The data for the halide ions, in particular, are quite useful and may be transferred to other halide systems, and give good predictive values for more complex systems. [Pg.1478]

The spectral area provides quantitative information on the amplitude and direction of motion of the probe nucleus through the final factor (k eja) in equation (3). This information can be determined for each mode using equation (3). Alternatively, further analysis of the data can yield an estimated vibrational density of states (VDOS)... [Pg.6253]

From rel. (2.4.6) it results that for the reaction indicated by rel. (2.4.6) gives a reasonable approximation for the formation of the radicals necessary for the initiation process. In other words, rel. (2.2.29) provides one of the necessary parameters in Arrhenius equation for quantitative information on kj. [Pg.104]

As you already know, the chemical equation provides a variety of qualitative and quantitative information essential for the calculation of the combining weights (mass) of materials involved in a chemical process. Take, for example, the combustion of heptane as shown below. What can we learn from this equation ... [Pg.65]

The above simple considerations explain the origin of the middle phase, the change In structure associated with Its occurrence, as well as the fluctuations of the Interface between the continuous and dispersed medium which arise in some single phase microenulsions. While It Is difficult to obtain detailed quantitative information on the above behaviour, the thermodynamic equations derived in the following section provide a framework for further theoretical development as well as some additional Insight concerning the micropressures and various physical quantities involved. [Pg.25]

Kinetics of nucleation may be studied by microscopic examinations of surfaces from which numbers of growth nuclei/unit area (N) are counted after known reaction times. Photographs of the surface may be taken at appropriate intervals and used to obtain the quantitative information. The nucleation law is sometimes also inferred from the overall kinetic behaviour. Precise fits to rate laws (including nucleation) require large numbers of accurate observations to enable reliable statistical analyses of the data to be made and it is frequently difficult to obtain sufficient numbers of reliable (N,t) values. The rate equations in Table 3.1. represent, to an acceptable approximation, all types of behaviour that can realistically be expected [10]. [Pg.80]

Quantitative information is obtained from the Randles-Sevcik equation, which at 25 °C is... [Pg.696]

A chemical equation for a reaction must be balanced before useful quantitative information can be obtained about the reaction. Balancing an equation ensures that the same number of atoms of each element appear on both sides of the equation. Many chemical equations can be balanced by trial and error, although some will involve more trial than others. [Pg.1149]


See other pages where Equation quantitative information is mentioned: [Pg.14]    [Pg.14]    [Pg.310]    [Pg.944]    [Pg.348]    [Pg.401]    [Pg.278]    [Pg.133]    [Pg.103]    [Pg.715]    [Pg.1027]    [Pg.46]    [Pg.84]    [Pg.19]    [Pg.69]    [Pg.111]    [Pg.14]    [Pg.493]    [Pg.278]    [Pg.91]    [Pg.51]    [Pg.84]    [Pg.6262]    [Pg.310]    [Pg.87]    [Pg.91]    [Pg.230]    [Pg.87]    [Pg.339]    [Pg.500]    [Pg.159]   


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