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Coefficients values

The representation of cooccurrence matrix as an image in 256 levels of gray necessitates a law of coefficients values transformation. In order that this law is common to all images, there will be no recodage on the maximum coefficient but on a theoretical maximal value. Thus the rule of conversion is the following ... [Pg.232]

In extraction (qv), the distribution coefficient value is the slope of the equiUbrium line. In practice, the slope of the operating line is set at a value somewhat less than the distribution coefficient to provide driving force and fix the required theoretical extraction stages at some reasonable number. [Pg.475]

Application of an infinite series to practical calculations is, of course, impossible, and truncations of the virial equations are in fact employed. The degree of truncation is conditioned not only by the temperature and pressure but also by the availability of correlations or data for the virial coefficients. Values can usually be found for B (see Sec. 2), and often for C (see, e.g., De Santis and Grande, ATChP J., 25, pp. 931-938 [1979]), but rarely for higher-order coefficients. Application of the virial equations is therefore usually restricted to two- or three-term truncations. For pressures up to several bars, the two-term expansion in pressure, with B given by Eq. (4-188), is usually preferred ... [Pg.529]

Fuller-Schettler-Giddings The parameters and constants for this correlation were determined by regression analysis of 340 experimental diffusion coefficient values of 153 binary systems. Values of X Vj used in this equation are in Table 5-16. [Pg.595]

Only fair overall coefficient values may be expected, although heat-flux values are good. [Pg.1091]

The Mix-R-Step type in Fig. ll-62e is an adaptation of avibratoiy conveyor. It features better heat-transfer rates, practically doubling the coefficient values of the standard flat surface and trebling heat-flux values, as the layer depth can be increased from the norm 13 to 25 and 32 mm (V2 to 1 and F in). It mav be provided on decks jacketed for air, steam, or water spray. It is also often apphcable when an infrared heat source is mounted overhead to supplement the indirect or as the sole heat source. [Pg.1097]

Strkcttire inflkence. The specificity of interphase transfer in the micellar-extraction systems is the independent and cooperative influence of the substrate molecular structure - the first-order molecular connectivity indexes) and hydrophobicity (log P - the distribution coefficient value in the water-octanole system) on its distribution between the water and the surfactant-rich phases. The possibility of substrates distribution and their D-values prediction in the cloud point extraction systems using regressions, which consider the log P and values was shown. Here the specificity of the micellar extraction is determined by the appearance of the host-guest phenomenon at molecular level and the high level of stmctural organization of the micellar phase itself. [Pg.268]

On the basis of data obtained the possibility of substrates distribution and their D-values prediction using the regressions which consider the hydrophobicity and stmcture of amines was investigated. The hydrophobicity of amines was estimated by the distribution coefficient value in the water-octanole system (Ig P). The molecular structure of aromatic amines was characterized by the first-order molecular connectivity indexes ( x)- H was shown the independent and cooperative influence of the Ig P and parameters of amines on their distribution. Evidently, this fact demonstrates the host-guest phenomenon which is inherent to the organized media. The obtained in the research data were used for optimization of the conditions of micellar-extraction preconcentrating of metal ions with amines into the NS-rich phase with the following determination by atomic-absorption method. [Pg.276]

Coefficients i (, cp, and (3 vary within a range from 0 to 1. The coefficient value depends on the heated surface temperature and emittance, and can be estimated from Table 7.2. [Pg.423]

The p coefficient value depends upon the supply air method (e.g., p = 0 with displacement and natural ventilation, P = 1 with convective plume dissipating within the occupied zone due to interaction with supply jets, airflows created by moving objects, etc.). [Pg.424]

For a building with sharp corners, Cp is almost independent of the wind speed (i.e., Reynolds number) because the flow separation points normally occur at the sharp edges. This may not be the case for round buildings, w here the position of the separation point can be affected by the wind speed. For the most common case of the building with a rectangular shape, Cp values are normally between 0.6 and 0.8 for the upwind wall, and for the leeward wall 0,6 < C, < —0.4. Figure 7.99 and Table 7.32 show an example of the distribution of surface pressure coefficient values on the typical industrial building envelope. [Pg.576]

FIGURE 7.99 Example of surface pressure coefficient values for a typical industrial building envelope. [Pg.576]

TABLE 7.32 Approximate Surface Pressure Coefficient Values for a Building with a Rooftop Vent... [Pg.577]

The K coefficient values for each of the items of pipe, bends, valves, fittings, contractions, enlargements, entrance/exits into/from vessels are additive as long as they are on the same size basis (see Table 2-2 and Figures 2-12A through 2-16). Thus the resistance equation is applicable to calculate the head or pressure loss through the specific system when the combined Rvalue is used. [Pg.81]

The usual range of film coefficient values is 40-50 for organic solvents and light petroleum fractions such as hexanes 25 for heavier materials such as aniline, straw oil, etc. and 0.5-3 for low temperature (10-40°F) subcooling of heavier organics and inorganics such as chlorine. [Pg.123]

When 1, 3, 3-triethoxypropene was hydrolyzed with IN sulfuric acid, a solution of malonaldehyde whose optical density was perfectly stable at 350 m/x for at least one week was obtained. If the solution was made alkaline, the optical density at the same wavelength increased by a small value and then remained virtually constant for at least one week (56). It was also observed that in these solutions the extinction coefficient at 350 m/x was very low (observed 8.3, 61.5 and 69, for solutions of pH 0.4, 7.15 and 9.4 respectively) compared with previously reported values which varied from 200 ( 40) to 1000 ( 48). On the other hand, the absorption of solutions having a pH of 3 to 5, increased considerably with time (at pH 4.75, the extinction coefficient of malonaldehyde at 350 m/x was initially about 40 after four weeks a value of about 930 was recorded and the optical density of the solution was still increasing). This increase in absorption was accompanied by a marked decrease in the malonaldehyde content of the solution, as measured by the thiobarbituric acid method. As a corollary, it was found that aqueous solutions of malonaldehyde, prepared by autocatalyzed hydrolysis (33) of the same acetal and which had a pH of about 3.5, showed, at the completion of the hydrolysis, considerably higher extinction coefficient values at 350 m/x than did those malonaldehyde solutions which were prepared by hydrolysis with IN acid and subsequently adjusted to pH 4. It appears, therefore, that at pH values at which most of the periodate oxidations are carried out, malonaldehyde is unstable and undergoes a chemical reaction, the nature of which is not, as yet, known. [Pg.112]

It should, however, be noted that as the concentration of the excess of precipitant increases, so too does the ionic strength of the solution. This leads to a decrease in activity coefficient values with the result that to maintain the value of Ks more of the precipitate will dissolve. In other words there is a limit to the amount of precipitant which can be safely added in excess. Also, addition of excess precipitant may sometimes result in the formation of soluble complexes causing some precipitate to dissolve. [Pg.28]

Comparing this with the equation for Newtonian fluids shows that the oxygen transfer coefficient for non-Newtonian fluids is less sensitive to power input changes. Thus, more power input is required to reach the same mass transfer coefficient value than in a Newtonian fluid. [Pg.27]

Constant or coefficient Value Constant or coefficient Value... [Pg.621]

The theory has been verified by voltammetric measurements using different hole diameters and by electrochemical simulations [13,15]. The plot of the half-wave potential versus log[(4d/7rr)-I-1] yielded a straight line with a slope of 60 mV (Fig. 3), but the experimental points deviated from the theory for small radii. Equations (3) to (5) show that the half-wave potential depends on the hole radius, the film thickness, the interface position within the hole, and the diffusion coefficient values. When d is rather large or the diffusion coefficient in the organic phase is very low, steady-state diffusion in the organic phase cannot be achieved because of the linear diffusion field within the microcylinder [Fig. 2(c)]. Although no analytical solution has been reported for non-steady-state IT across the microhole, the simulations reported in Ref. 13 showed that the diffusion field is asymmetrical, and concentration profiles are similar to those in micropipettes (see... [Pg.382]

Selectivity coefficients values for K - and Na -ISFETs with the optimized ion-sen-sing membranes encapsulating valinomycin and bis(12-crown-4) are summarized in Fig. 9. The selectivity coefficient for with respect to Na in the K -ISFET is 2 x 10 " and that for Na with respect to in the Na -ISFET is 3 x 10. The selectivity coefficient values are similar to those for the ISFETs and ion-selective electrodes with the previous membrane materials containing the same neutral carriers. The high sensitivity and selectivity for the neutral-carrier-type ISFETs based on sol-gel-derived membranes can last for at least 3 weeks. [Pg.594]

It should finally be noted that the amount of the neutral and zweitterionic forms of a compound in solution is determined by its tatuomeric equilibrium constant, defined as Kz = cz/cn. Therefore, the neutral species and the zwitterion coexist around the isoelectric pH, and membrane permeation is conditioned by Kx and by the partition coefficient values of both tautomers. [Pg.755]


See other pages where Coefficients values is mentioned: [Pg.1117]    [Pg.531]    [Pg.95]    [Pg.1093]    [Pg.1093]    [Pg.1093]    [Pg.276]    [Pg.268]    [Pg.1086]    [Pg.55]    [Pg.489]    [Pg.46]    [Pg.47]    [Pg.172]    [Pg.486]    [Pg.363]    [Pg.319]    [Pg.522]    [Pg.227]    [Pg.394]    [Pg.744]    [Pg.745]    [Pg.746]    [Pg.750]    [Pg.751]    [Pg.754]    [Pg.502]    [Pg.254]   
See also in sourсe #XX -- [ Pg.280 ]




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