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Early Theoretical Analysis

This section presents early theoretical analysis of simple distillation, which was first analyzed by [35]. [Pg.43]


A detailed theoretical study of the properties of the redox system FeS/FeS2 was carried out in the Department of Geosciences of SUNY Stony Brook (Schoonen et al., 1999). The authors conclude that the hypothetical reduction of CO2 (by the FeS/FeS2 redox pair) formulated in Wachtershauser s early work, and the carbon fixation cycle on the primeval Earth associated with it, probably could not have occurred. This judgement is made on the basis of a theoretical analysis of thermodynamic data other conditions would naturally have been involved if CO had reacted rather than C02. It is not known whether free CO existed in the hydrosphere, or if so, at what concentrations. [Pg.201]

Characterization of amide vibrational modes as seen in IR and Raman spectra has developed from a series of theoretical analyses of empirical data. The designation of amide A, B, I, II, etc., modes stem from several early studies of the (V-methyl acetamide (NMA) molecule vibrational spectra which continues to be a target of theoretical analysis. 15 27,34 162 166,2391 Experimental frequencies were originally fitted to a valence force field using standard vibrational analysis techniques and subsequently were compared to ab initio quantum mechanical force field results. [Pg.723]

Very early, Miller and Bruckenstein [6] had felt that for an electrochemical system under mixed kinetic control, HMRDE was able to derive information about the kinetic parameters and give more valuable interpretation than by conventional RDE technique. At that time, they developed a theoretical analysis, restricted to quasi steady state, and which is now presented in a more quantitative way and over a large frequency domain with the formalism of EHD impedance (see Chapter 4). [Pg.244]

From a theoretical analysis of the intermediate stages during which the solute is being redistributed, Archibald136 has developed a technique which involves measurements at intervals during the early stages of the sedimentation equilibrium experiment and so does not entail a long wait for equilibrium to be established. The ratio s/D can be calculated from the expression... [Pg.36]

The early theoretical study of Peri and Hensley,2 performing a Monte Carlo analysis on the idealized 111 and 100 faces of cristobalite concluded that 85 % to 95 % of all surface silanols are paired (geminal), whereas the earlier study of De Boer and Vleeskens10 modelled the 0001 face of /3-cristobalite to conclude that no geminal hydroxyls are present at all. [Pg.60]

Another potential image sensor is the CCD discussed in Chapter 9 by Matsumura. The major problem in using a-Si H for CCD applications is the high density of traps or localized states in the band gap. A theoretical analysis assuming an exponential distribution of gap states permits us to predict the transfer characteristics (residual electron density as a function of time). With state-of-the-art material it should be possible to make usable image sensors. Early experimental results with novel test structures have yielded transfer inefficiencies of less than 1% at clock frequencies between 1 and 200 kHz. [Pg.4]

One of the key tools in evaluating virtual screening performance is some measure of enrichment, whether by ROC curves, enrichment factor and so on. What one wants to know is whether a screening method identifies the actives early in the overall prioritised list of compounds. Truchon and Bayley" have performed a theoretical analysis to show that ROC curves may not be ideal for this purpose, despite their widespread use (and advocacy). A method can get a good ROC score, yet still fail to identify any actives in the top 20%. They propose a new metric based on an enhanced form of the ROC curve called BEDROC, which, via a parameter... [Pg.56]

High flexibility (modular design), effective feeding, devolatilization, mixing, reactive processing Difficult fabrication, cost up to lOx that of SSE, early stage of the theoretical analysis, poor back mixing (narrow residence time distribution), require accurate feeders... [Pg.618]

It is too early to decide whether semiempirical computations can successfully evaluate TS models such as 117-124 given the current level of precision. This situation is likely to change as the theoretical methods refine their phosphorus parameters and their ability to mimic solvation effects. Table 22 provides many opportunities to test computational TS predictions. Selectivity in the Wittig reaction depends on substituents, not on some fundamental property of phosphorus ylides. Thus, any successful theoretical analysis of the selectivity issue will need to explain the substituent-induced differences in kinetic Z E ratios. [Pg.146]

Early attempts at theoretical analysis of the effects of cell motility on population growth centered on uptake of nutrient by a single cell in a medium of infinite extent (12, 24, 25, 26). These analyses have... [Pg.273]


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Theoretical analysis

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