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Separation 501 - evaluation

Once a design is known for the first two layers of the onion (i.e., reactors and separators only), the overall total cost of this design for all four layers of the onion (i.e., reactors, separators, heat exchanger network, and utilities) is simply the total cost of all reactors and separators (evaluated explicitly) plus the total cost target for heat exchanger network and utilities. [Pg.236]

A researcher formulating a strategy for a particular company must determine what portion of the planned output will be sold by its sales force and whether distributors or manufacturers representatives might be beneficial. If it appears that a distributor or agent is needed, a separate evaluation of the capabihties of representative companies or individuals should be made. [Pg.537]

Finally, a constraint analysis has been developed to screen new opportunities (57). This analysis separately evaluates intrinsic business attractiveness factors and the fit factors required for commercial success. [Pg.131]

Gas can be condensed by (a) mechanically refrigerating it, (b) compressing and expanding it, using turboexpanders, or, (c) pressure effects such as by Joule-Thomson cooling and overcoming the vapor pressure. The liquefaction of methane can involve all three of these effects. These effects can be separately evaluated to show the effectiveness of each in producing liquid. [Pg.42]

A fault tree is a graphical form of a Boolean equation, but the probability of the top event (and lesser events) can be found by substituting failure rates and probabilities for these iwo-staie events. The graphical fault tree is prepared for computer or manual evaluation by pruning" it of less significant events to focus on more significant events. Even pruned, the tree may be so large that it IS intractable and needs division into subtrees for separate evaluations. If this is done, care must be taken to insure that no information is lost such as interconnections between subtrees. [Pg.111]

A separate evaluation of PIFs needs to be performed in order to predict which error types are likely. [Pg.195]

Establish actual relieving pressure (and corresponding temperature) from Figure 7-7A (at 110% of set pressure for non-fire and non-explosive conditions). Explosive conditions may require total separate evaluation of the set pressure never above the MAWP), which should be lower or staged or, most likely, will not be satisfied by a standard SRV due to the extreme rapid response needed. [Pg.438]

Organic peroxides and hydroperoxides decompose in part by a self-induced radical chain mechanism whereby radicals released in spontaneous decomposition attack other molecules of the peroxide.The attacking radical combines with one part of the peroxide molecule and simultaneously releases another radical. The net result is the wastage of a molecule of peroxide since the number of primary radicals available for initiation is unchanged. The velocity constant ka we require refers to the spontaneous decomposition only and not to the total decomposition rate which includes the contribution of the chain, or induced, decomposition. Induced decomposition usually is indicated by deviation of the decomposition process from first-order kinetics and by a dependence of the rate on the solvent, especially when it consists of a polymerizable monomer. The constant kd may be separately evaluated through kinetic measurements carried out in the presence of inhibitors which destroy the radical chain carriers. The aliphatic azo-bis-nitriles offer a real advantage over benzoyl peroxide in that they are not susceptible to induced decomposition. [Pg.113]

Once a design is known for the reaction and separation systems, the overall total cost is the total cost of all reactors and separators (evaluated explicitly) plus the total cost target for heat exchanger network. [Pg.396]

When a solid is capable of decomposing by means of several discrete, sequential reactions, the magnitude of each step can be separately evaluated. Thermogravimetric analysis of compound decomposition can also be used to compare the stability of similar compounds. The higher the decomposition temperature of a given compound, the more positive would be the DG value and the greater would be its stability. [Pg.245]

Some complications arise from the presence of proton donor-acceptor interactions134 when the donor is a protic amine. The separate evaluation of the two kinds of interactions may be a difficult problem. Similarly, if the electron acceptor is also a proton donor, the overlapping of salification and complexation processes makes the separate investigation of the interactions very difficult. This is the case in the complexes between amines and picric acid or other related phenols. For complexes of 2,4,6-trinitro-3-hydroxypyridine135 and... [Pg.439]

Topsom, 1976) and to treat them separately. In this review we will be concerned solely with polar or electronic substituent effects. Although it is possible to define a number of different electronic effects (field effects, CT-inductive effects, jt-inductive effects, Jt-field effects, resonance effects), it is customary to use a dual substituent parameter scale, in which one parameter describes the polarity of a substituent and the other the charge transfer (resonance) (Topsom, 1976). In terms of molecular orbital theory, particularly in the form of perturbation theory, this corresponds to a separate evaluation of charge (inductive) and overlap (resonance) effects. This is reflected in the Klopman-Salem theory (Devaquet and Salem, 1969 Klop-man, 1968 Salem, 1968) and in our theory (Sustmann and Binsch, 1971, 1972 Sustmann and Vahrenholt, 1973). A related treatment of substituent effects has been proposed by Godfrey (Duerden and Godfrey, 1980). [Pg.132]

Lim, H. S. Pickett, D. F. Separator Evaluation in NiCd Cells. Proceedings of the Intersociety Energy Conversion Engineering, IEEE New York, 1990 Vol. 3, p 61. [Pg.222]

The approach proposed by Renwick (1991, 1993) is also based on the 100-fold factor. It attempts to give a scientihc basis to the default values of 10 for the interspecies and 10 for the intraspecies (interindividual human) differences. Renwick also proposed a division of each of these UEs into sub-factors to allow for separate evaluations of differences in toxicokinetics and toxicodynamics. The advantage of such a subdivision is that components of these UEs can be addressed where data are available for example, if available data show similar toxicokinetics of a given chemical in experimental animals and humans, then only an interspecies extrapolation factor would be needed to account for differences in toxicodynamics. Renwick examined the relative magnitude of toxicoki-netic and toxicodynamic variations between and within species in detail. He found that toxicokinetic differences were generally greater than toxicodynamic differences resulting in the proposal that the 10-fold factors (for inter- and intraspecies variation) should, by default, be subdivided into factors of 4 for toxicokinetics and 2.5 for toxicodynamics. It should be noted that the proposed default values were derived from limited data. [Pg.217]

Having V, Vq, and data from a series of experiments, separately evaluate the left side and the right side of Eq. (i). For the right side, at various Z ... [Pg.108]

The limits of the electrochromatographic retention factor defined by Equation 6.54 are that both k and must be separately evaluated under specific experimental conditions used in CEC. These limitations can be avoided describing the retention of analytes in CEC by a peak locator that can be evaluated directly from the electrochromatogram as follows [256] ... [Pg.199]

In 45 patients with known colorectal cancer. Cohade etal. [28] compared retrospectively the accuracies for staging and restaging of [ F]-FDG-PET/CT versus [1 F]-FDG-PET alone. All p F]-FDG-PET and [ F]-FDG-PET/CT studies were separately evaluated in randomized order. [ Ge] attenuation-corrected images were assessed to reassure that only the added value of CT information was... [Pg.148]

Figure 2 shows the marker by treatment interaction design discussed by Sargent et al. (18) and by Pusztai and Hess (19). Both marker positive and marker negative patients are randomized to the experimental treatment or control. The analysis plan either calls for separate evaluation of the treatment difference in the two-marker strata or for testing the hypothesis that the treatment effect is the same in both marker strata. [Pg.335]

Surface polarity can also be independently evaluated by physical means. deMayo and coworkers have assigned surface polarity of silica gel particles by observing shifts in the absorption spectra of absorbed spiropyrans which are sensitive to solvent polarity . Darwent and coworkers have shown that kinetic salt effects follow surface charge on colloidal titanium dioxide and, with zeta potential measurements, that surface area and charge could be separately evaluated... [Pg.79]

To this end we and our collaborators have repeatedly scrutinized every bit of information recorded here. We have separately evaluated the conformity of the apparatus and experimental techniques to the best modern standards, the accuracy of the handling of the data obtained, the certainty with which products and intermediates were identified, the strength of the evidence given for each suggested reaction course or mechanism, and every other point that the published description of each research allowed us to check. [Pg.734]

After evaluation of the net solar heat input rates to the salt water, as monthly averages (or more frequently if desired), they and the atmospheric temperature averages are substituted in Equations 5 and 6. The two equations can then be solved by trial for the mean basin and cover temperatures each month. Distillation rate is then Qbtained by substitution of these values in Equation 4. The first and second terms on the right-hand side of Equation 5 may be separately evaluated for convection and radiation losses from basin to cover. [Pg.165]

By comparing the three sets of results obtained by the different protocols (Tables 8.1 and 8.2), we conclude that the separate determinations using calorimetric and infrared data do not result in the same reaction parameters. It is, therefore, essential to apply the combined protocol in order to obtain a single set of reaction parameters that represents an optimal solution for all measured data. Note also that some of the reaction parameters (ArHi, ArH2, k and Eaj) determined by the combined protocol are outside the range defined by the separate ones. It would be unreasonable, therefore, simply to average the reaction parameters of the separate evaluations in order to obtain a single set. [Pg.220]


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See also in sourсe #XX -- [ Pg.133 ]




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