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Summary coefficients

In summary, the so-called Einstein A and B rate coefficients connecting a lower-energy initial state i and a final state f are related by the following conditions ... [Pg.393]

Correlations for Convective Heat Transfer. In the design or sizing of a heat exchanger, the heat-transfer coefficients on the inner and outer walls of the tube and the friction coefficient in the tube must be calculated. Summaries of the various correlations for convective heat-transfer coefficients for internal and external flows are given in Tables 3 and 4, respectively, in terms of the Nusselt number. In addition, the friction coefficient is given for the deterrnination of the pumping requirement. [Pg.483]

Many of the physical properties are not affected by the optical composition, with the important exception of the melting poiat of the crystalline acid, which is estimated to be 52.7—52.8°C for either optically pure isomer, whereas the reported melting poiat of the racemic mixture ranges from 17 to 33°C (6). The boiling poiat of anhydrous lactic acid has been reported by several authors it was primarily obtained duriag fractionation of lactic acid from its self-esterification product, the dimer lactoyUactic acid [26811-96-1]. The difference between the boiling poiats of racemic and optically active isomers of lactic acid is probably very small (6). The uv spectra of lactic acid and dilactide [95-96-5] which is the cycHc anhydride from two lactic acid molecules, as expected show no chromophores at wavelengths above 250 nm, and lactic acid and dilactide have extinction coefficients of 28 and 111 at 215 nm and 225 nm, respectively (9,10). The iafrared spectra of lactic acid and its derivatives have been extensively studied and a summary is available (6). [Pg.512]

Fig. 7. Toxicity of chlorine to aquatic organisms, (a) Time-dependent mortaUty (50%) of four example species in various levels of total residual chlorine in the laboratory, where for A, A.losa aestivalis and B, Salmogairdnerii r (correlation coefficient of the curve) = —0.96 and for C, P/euroneetesplatessa and D, Salmo trutta r = —0.98. (b) A summary of chlorine toxicity to freshwater species, indicating overall no-effect thresholds for acute and chronic exposures. Numbers indicate where more than one test yielded the same result. A different summary figure appHes to marine organisms because of differences in the... Fig. 7. Toxicity of chlorine to aquatic organisms, (a) Time-dependent mortaUty (50%) of four example species in various levels of total residual chlorine in the laboratory, where for A, A.losa aestivalis and B, Salmogairdnerii r (correlation coefficient of the curve) = —0.96 and for C, P/euroneetesplatessa and D, Salmo trutta r = —0.98. (b) A summary of chlorine toxicity to freshwater species, indicating overall no-effect thresholds for acute and chronic exposures. Numbers indicate where more than one test yielded the same result. A different summary figure appHes to marine organisms because of differences in the...
A summary of physical and chemical constants for beryUium is compUed ia Table 1 (3—7). One of the more important characteristics of beryUium is its pronounced anisotropy resulting from the close-packed hexagonal crystal stmcture. This factor must be considered for any property that is known or suspected to be stmcture sensitive. As an example, the thermal expansion coefficient at 273 K of siagle-crystal beryUium was measured (8) as 10.6 x 10 paraUel to the i -axis and 7.7 x 10 paraUel to the i -axis. The actual expansion of polycrystalline metal then becomes a function of the degree of preferred orientation present and the direction of measurement ia wrought beryUium. [Pg.65]

The kind of convective heat transfer—forced convection or natural (at floor, wall, or ceiling)—must be considered and taken into account by selecting appropriate values for the convective heat transfer coefficient see Eq. (11.14)). Thus, the heat transfer coefficient implicitly assumes the flow situation at the surface. Normally, coefficients for convective heat transfer are considered as a preset constant parameter (the coefficient may be defined as variable, however, depending on other parameters). Therefore, the selection of appropriate values is crucial. Values for heat transfer coefficients can be found in several references a comprehensive summary is given in Daskalaki. ... [Pg.1063]

Panagiotopoulos et al. [16] studied only a few ideal LJ mixtures, since their main objective was only to demonstrate the accuracy of the method. Murad et al. [17] have recently studied a wide range of ideal and nonideal LJ mixtures, and compared results obtained for osmotic pressure with the van t Hoff [17a] and other equations. Results for a wide range of other properties such as solvent exchange, chemical potentials and activity coefficients [18] were compared with the van der Waals 1 (vdWl) fluid approximation [19]. The vdWl theory replaces the mixture by one fictitious pure liquid with judiciously chosen potential parameters. It is defined for potentials with only two parameters, see Ref. 19. A summary of their most important conclusions include ... [Pg.781]

Other important equations of state which can be related to fugacity and activity have been developed by Redlich-Kwong [56] with Chueh [10], which is an improvement over the original Redlich-Kwong, and Palmer s summary of activity coefficient methods [51]. [Pg.12]

In summary, then, a beam of 7-rays may be attenuated by three independent processes so that the mass absorption coefficient is written as the sum of three terms ... [Pg.290]

A summary of a number of correlations proposed for volumetric mass-transfer coefficients and specific interfacial area is presented in Table II, which includes data additional to those of Westerterp et al. (W4). It is apparent that disagreement exists as to the numerical values for the exponents. This is due, in part, to the lack of geometric similarity in the equipment used. In addition, variation in operating factors such as the purity of the system (surfactants), kind of chemical system, temperature, etc., also contribute to the discrepancies. To summarize Table II ... [Pg.306]

The conclusion that the nitration of quinoline in sulphuric acid takes place via the conjugate acid has been confirmed by Moodie et al.50, who measured the rates of nitration of a wide range of heterocyclic compounds in nitric acid-sulphuric acid mixtures at a range of temperatures. A summary of the second-order rate coefficients and Arrhenius parameters is given in Table 4. From an analysis of the shapes of the plots of log k2 versus sulphuric acid acidity (or some function of this), it was concluded that all of the compounds starred in Table 4... [Pg.15]

There was considerable corridor discussion after a presentation by Dr. G. L. Silver, who "got the attention of the audience" by taking plutonium chemists to task concerning (according to him) their erroneous use of a (too) simplified summary equation involving the disproportionation of Pu(IV) and their lack of appreciation of alpha coefficients. Dr. Silver stressed the use of alpha coefficients and equations which explicitly involve acidity, hydrolysis of Pu(IV), and especially the presence of Pu(V), which is too frequently ignored. [Pg.447]

In summary, the temperature rises AT,- and the heat partition coefficient f(x, y, t) can be determined through solving Eqs (18) and (19) simultaneously with (22) or (23), if the heat flux qix, y, t) has been given in advance. In the simplest way, an estimation of heat generation can be made by calculating frictional work in terms of experiential friction coefficients. [Pg.120]

For the data the squared correlation coefficient was 0.93 with a root mean square error of 2.2. The graph of predicted versus actual observed MS(1 +4) along with the summary of fit statistics and parameter estimates is shown in Figure 16.7. [Pg.494]

In summary, therefore, the KS suspension test differs from the RW and CM tests in that it is a capacity test, it reports the data as a pass or fail and not as a numerical cipher, i.e. not as a coefficient, and it uses a range of microorganisms. It combines an individual feature ofthe RW and CM tests in that it can report on disinfectant activity under both clean and dirty conditions. [Pg.238]

In summary, the Fourier transform of a continuous signal digitized in 2A/ + 1 data points returns N real Fourier coefficients, N imaginary Fourier coefficients and the average signal, also called the DC term, i.e. in total 2N + 1 points. The relationship between the scales in both domains is shown in Fig. 40.9. [Pg.521]

Table 6. Summary of partition coefficients for U-series elements or their proxies. Table 6. Summary of partition coefficients for U-series elements or their proxies.
In summary, a key aspect to the utility of U-series isotopes in the study of arc lavas is that whereas Th and Pa are observed and predicted to behave as relatively immobile high field strength elements (HFSE), Ra and (under oxidizing conditions) U behave like large ion lithophile elements (LILE) and are significantly mobilized in aqueous fluids. Fluid-wedge interaction will only serve to increase these fractionations. Just how robust the experimental partition coefficients are remains to be established by future experiments. [Pg.269]

In summary, at each iteration of the estimation method we compute the model output, y(x kw), and the sensitivity coefficients, G for each data point i=l,...,N which are used to set up matrix A and vector b. Subsequent solution of the linear equation yields Akf f 1 and hence k[Pg.53]

Summary of experimental data Film boiling correlations have been quite successfully developed with ordinary liquids. Since the thermal properties of metal vapors are not markedly different from those of ordinary liquids, it can be expected that the accepted correlations are applicable to liquid metals with a possible change of proportionality constants. In addition, film boiling data for liquid metals generally show considerably higher heat transfer coefficients than is predicted by the available theoretical correlations for hc. Radiant heat contribution obviously contributes to some of the difference (Fig. 2.40). There is a third mode of heat transfer that does not exist with ordinary liquids, namely, heat transport by the combined process of chemical dimerization and mass diffusion (Eq. 2-162). [Pg.145]

Table 1 Summary of Experimental Methods for Evaluating Diffusion Coefficients and Investigating Mass Transport Processes of Pharmaceutical Interest... [Pg.121]

The summary of Pe values for the steroids as a function of stirring rates is found in Table 11 and their correlations with log PC (n-octanol-water) in Figure 20. The transport kinetics of the relatively hydrophilic hydrocortisone and dexa-methasone are controlled by passive diffusion across the cell monolayer. On the other hand, the Pe values of testosterone and progesterone are highly dependent on stirring rate. The results for testosterone are used to obtain the relationships between the effective permeability coefficients of the ABL on the donor and receiver sides and the stirring rate, using the linear expression (see Eq. (69)]... [Pg.284]

In summary, models can be classified in general into deterministic, which describe the system as cause/effect relationships and stochastic, which incorporate the concept of risk, probability or other measures of uncertainty. Deterministic and stochastic models may be developed from observation, semi-empirical approaches, and theoretical approaches. In developing a model, scientists attempt to reach an optimal compromise among the above approaches, given the level of detail justified by both the data availability and the study objectives. Deterministic model formulations can be further classified into simulation models which employ a well accepted empirical equation, that is forced via calibration coefficients, to describe a system and analytic models in which the derived equation describes the physics/chemistry of a system. [Pg.50]

Results of adsorption experiments for butylate, alachlor, and metolachlor in Keeton soil at 10, 19, and 30°C were plotted using the Freundlich equation. A summary of the coefficients obtained from the Freundlich equation for these experiments is presented in TABLE IV. Excellent correlation using the Freundlich equation over the concentration ranges studied (four orders of magnitude) is indicated by the r values of 0.99. The n exponent from the Freundlich equation indicates the extent of linearity of the adsorption isotherm in the concentration range studied. If n = 1 then adsorption is constant at all concentrations studied (the adsorption isotherm is linear) and K is equivalent to the distribution coefficient between the soil and water (Kd), which is the ratio of the soil concentration (mole/kg) to the solution concentration (mole/L). A value of n > 1 indicates that as the solution concentration increases the sorption sites become saturated, resulting in a disproportionate amount of chemical being dissolved. Since n is nearly equal to 1 in these studies, the adsorption isotherms are nearly linear and the values for Kd (shown in TABLE IV) correspond closely to K. These Kd values were used to calculate heats of adsorption (AH). [Pg.238]

Table 2 Summary of temperature coefficients determined from Arrhenius plots of chemiluminescence intensity vs. temperature plots... Table 2 Summary of temperature coefficients determined from Arrhenius plots of chemiluminescence intensity vs. temperature plots...
Table 33-1 Summary of results obtained from synthetic linearity data using one PCA or PLS factor. We present only those performance results listed by the data analyst as Correlation Coefficient and Standard Error of Estimate... Table 33-1 Summary of results obtained from synthetic linearity data using one PCA or PLS factor. We present only those performance results listed by the data analyst as Correlation Coefficient and Standard Error of Estimate...
Thus a comparison of the correlation coefficient between two or more sets of X, Y data pairs cannot be adequately performed unless the standard deviations of the two data sets are nearly identical or unless the correlation coefficient confidence limits for the data sets are compared. In summary, if one Set A of X, Y paired data has a correlation of 0.95, this does not necessarily indicate that it is more highly correlated than a second Set B of X, Y paired data with a correlation of say 0.90. The meaning of this will be described in greater detail later. [Pg.385]

In summary, for any stated value of the population correlation (p) the z statistic is denoted as Z(p), and the corresponding correlation confidence limits can be determined. For our example, the Z statistic of 0.6366 corresponding to the lower correlation coefficient confidence limit is shown in the graphic below (Graphic 60-6a) as having a p value of 0.562575 this represents the lower confidence limit for the correlation coefficient for this example. [Pg.394]

Summary of Experimental Results for the Diffusion Coefficient of 218Po... [Pg.149]

The studies involved determining appropriate environmental pathways that would result in exposure to humans, determining appropriate occupancy factors (number and distribution) within structures, characterizing the source term for each property, selecting an appropriate set of health risk coefficients, calculating health effects, and providing summary reports of potential health effects for each vicinity property. [Pg.515]

In Eq. (17), Dip(Ci) is the concentration-dependent diffusion coefficient its form of concentration dependence is affected by the structural characteristics of the polymer carrier. A selective summary of the various forms of the diffusion coefficient is provided in Table I. [Pg.85]

A wide variety of solubilities (in units of g/m3 or the equivalent mg/L) have been reported. Experimental data have the method of determination indicated. In other compilations of data the reported value has merely been quoted from another secondary source. In some cases the value has been calculated. The abbreviations are generally self-explanatory and usually include two entries, the method of equilibration followed by the method of determination. From these values a single value is selected for inclusion in the summary data table. Vapor pressures and octanol-water partition coefficients are selected similarly. [Pg.29]

Summary of literature data Ebulliometry Selected values GC det d activity coefficient ... [Pg.302]


See other pages where Summary coefficients is mentioned: [Pg.262]    [Pg.262]    [Pg.153]    [Pg.75]    [Pg.242]    [Pg.117]    [Pg.79]    [Pg.571]    [Pg.1236]    [Pg.93]    [Pg.357]    [Pg.339]    [Pg.517]    [Pg.465]    [Pg.131]    [Pg.248]   
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