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Point value

The original motivation [7] for using was to compensate for the inaccuracies arising from evaluating at point values of... [Pg.325]

Local average values of concentrations and partial pressures, rather chan point values, are also used in Che flux relations. However, in this case it is convenient to use interstitial local averages, based on the void volume rather than the total volume, since these are. ore closely related to the properties of bulk gases. [Pg.10]

This table lists the and pi (pH at the isoelectric point) values of a-amino acids commonly found in proteins along with their abbreviations. The dissociation constants refer to aqueous solutions at 25°C. [Pg.1179]

Design Procedure. The packed height of the tower required to reduce the concentration of the solute in the gas stream from to acceptable residual level ofjy 2 may be calculated by combining point values of the mass transfer rate and a differential material balance for the absorbed component. Referring to a sHce dh of the absorber (Fig. 5),... [Pg.25]

The average slopes and m from Figures 7 and 8 may also be used in equation 54 to compute although equation 50, with some suitable should be preferred. Use of point values at an effective average Hquid concentration given by equation 59 is suggested. [Pg.28]

Thermal Properties. Because all limestone is converted to an oxide before fusion or melting occurs, the only melting point appHcable is that of quicklime. These values are 2570°C for CaO and 2800°C for MgO. Boiling point values for CaO are 2850°C and for MgO 3600°C. The mean specific heats for limestones and limes gradually ascend as temperatures increase from 0 to 1000°C. The ranges are as follows high calcium limestone, 0.19—0.26 dolomitic quicklime, 0.19—0.294 dolomitic limestone, 0.206—0.264 magnesium oxide, 0.199—0.303 and calcium oxide, 0.175—0.286. [Pg.166]

Example 14 Estimate of etbyl acetate at 450 K, using tbe normal boiling point values as a basis (see Example 13). = 32.23 kJ/mol, T,. =... [Pg.394]

Although the point values of the rate diminish with p, in the steady state the rate of reaction equals the rate of diffusion at the mouth of the pores. The effectiveness of the catalyst is a ratio... [Pg.2096]

In order to allow integration of countercurrent relations like Eq. (23-93), point values of the mass-transfer coefficients and eqiiilibrium data are needed, over ranges of partial pressure and liquid-phase compositions. The same data are needed for the design of stirred tank performance. Then the conditions vary with time instead of position. Because of limited solubihty, gas/liquid reactions in stirred tanks usually are operated in semibatch fashion, with the liquid phase charged at once, then the gas phase introduced gradually over a period of time. CSTR operation rarely is feasible with such systems. [Pg.2110]

Rule 7. Determine the pre-exponential term by setting all variables to center point value, where everything becomes one except the pre-exponential factor, because ... [Pg.142]

Mettler softening point provides the lowest for a given resin. Therefore, both the softening point value and the method used for its determination should be given. In general, manufacturers supply the resins with a tolerance of about 3°C in the Ring and Ball (R B) softening point. [Pg.614]

Figure 2.5-1 illustrates the fact that probabilities are not precisely known but may be represented by a "bell-like" distribution the amplitude of which expresses the degree of belief. The probability that a system will fail is calculated by combining component probabilities as unions (addition) and intersection (multiplication) according to the system logic. Instead of point values for these probabilities, distributions are used which results in a distributed probabilitv of system fadure. This section discusses several methods for combining distributions, namely 1) con olution, 2i moments method, 3) Taylor s series, 4) Monte Carlo, and 5) discrete probability distributions (DPD). [Pg.56]

When the point values are average probabilities, the overall result from combining system.s as combinations of sequences and redundancies is found by simply combining the mean probabiliiies according to the arithmetic operations. [Pg.57]

Accident Sequence Quantification estimates the IE frequency. Specifically, the plant model built in the Step 2 is quantified by data from Step 3 according to Boolean algebra. Quantification may be a point-value calculation in which all parameters are delermimsiic, or as uncertain values known by their distribution function. [Pg.447]

The weep point for sieve or valve trays is the vapor rate at which the liquid weeping rate is diminished to zero. Thus, J L approaches zero asJ G is increased [210]. For a vapor rate that leads to J g higher than the weep point value, then there should be no weeping. [Pg.184]

Point Value (IPS-peak) Point Value (IPS-peak)... [Pg.728]

Arrange these compounds in order of increasing boiling point. Values in °C are 0,11, and 97. [Pg.608]

For very weak acids however, e.g. boric acid [trioxoboric(III) acid], the initial conductance is very small but increases as the neutralisation proceeds owing to the salt formed. The conductance values near the equivalence point are high because of hydrolysis beyond the equivalence point the hydrolysis is considerably reduced by the excess alkali. To determine the end point, values of the conductance considerably removed from the equivalence point must therefore be used for extrapolation. [Pg.526]

If each value of/, as given by Eq. (4-150), is multiplied by the same arbitrary scale factor, Eq. (4-149) is still satisfied actually Eq. (4-146) is also independent of a scale factor in the fr Substituting Eq. (4-150) into (4-146), we note that the two sums are equal and the stationary point value of E,EST simplifies to... [Pg.236]

The reaction follows a mixed second-order rate law. The progress was monitored spec-trophotometrically at 723 nm, where Np4+ has a maximum absorption. The following data refer to an experiment with [Np3+]o = 1.53 x 10-4 M, [Fe3+]o = 2.24 x 10-4 M (taken at 298.0 K, [H+] = 0.400 M, and ionic strength = 2.00 M). Calculate the rate constant either taking the end point value as 0.351 or, if a suitable program is available, allowing it to be found in the calculation. [Pg.41]

As shown earlier, the melting point for perfectly linear ADMET polyethylene (Table 8.1) approaches the range of melting point values exhibited by industrially produced, highly linear polyethylenes.40 However, for ADMET polyethylene with a methyl branch placed on every ninth carbon, the 7m is lowered significantly. The melting point of — 14°C and enthalpy of 28 J/g is 150°C and approximately... [Pg.449]

These expressions give point values of h and Nux at x = x. It is seen that the coefficient decreases from a theoretical value of infinity at the top as the condensate film thickens. The mean value of the heat transfer coefficient over the whole surface, between r = 0 and jc = x is given by ... [Pg.473]

To evaluate the required condenser area, point values of the group UAT as a function of qc must be determined by a trial and error solution of equation 9.181. Integration of a plot of qc against 1/17AT will then give the required condenser area. This method takes into account point variations in temperature difference, overall coefficient and mass velocities and consequently produces a reasonably accurate value for the surface area required. [Pg.478]

From a knowledge of hg,kG, and h0 and for a given Ts and Tcm values of the condensate surface temperature Tc are estimated until equation 9.181 is satisfied. The calculations are repeated, and in this manner several point values of the group UAT throughout the condenser may be obtained. [Pg.479]

The point value of the mass transfer coefficient is therefore >jD/nt. [Pg.605]

That is, the average rate over the time interval t --= 0 to r — te is twice the point value at... [Pg.606]

Equations 10.142 and 10.143 give the point value of NA at time t. The average values Na can then be obtained by applying the age distribution functions obtained by Higbie and by Danckwerts, respectively, as discussed Section 10.5.2. [Pg.616]

Equation 11.21 gives the point values of R and R/pu2s at x = x. In order to calculate the total frictional force acting at the surface, it is necessary to multiply the average value of R between x = 0 and x = x by the area of the surface. [Pg.674]

It is seen from equation 11.66 that the heat transfer coefficient theoretically has an infinite value at the leading edge, where the thickness of the thermal boundary layer is zero, and that it decreases progressively as the boundary layer thickens. Equation 11.66 gives the point value of the heat transfer coefficient at a distance x from the leading edge. The mean value between. v = 0 and x = x is given by ... [Pg.690]


See other pages where Point value is mentioned: [Pg.184]    [Pg.42]    [Pg.488]    [Pg.717]    [Pg.1326]    [Pg.1382]    [Pg.56]    [Pg.290]    [Pg.197]    [Pg.623]    [Pg.786]    [Pg.143]    [Pg.234]    [Pg.1012]    [Pg.184]    [Pg.719]    [Pg.206]    [Pg.234]    [Pg.362]    [Pg.434]    [Pg.537]    [Pg.608]   
See also in sourсe #XX -- [ Pg.345 , Pg.619 ]




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Point valued

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