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Three scheme

All three schemes, the Benson, the Laidler, and the Allen scheme, use four structure contributions for the estimation of thermochemical data of alkanes. As might be guessed, they are numerically equivalent all three schemes provide the same accuracy. This is shown below by Eqs. (7)-(10) for the interconversion of the various contributions. [Pg.325]

There is little experience with the von Niessen method, but for most molecules the remaining three schemes tend to give very similar LMOs. The main exception is systems containing both a- and vr-bonds, such as ethylene. The Pipek-Mezey procedure preserves the cr/yr-separation, while the Edmiston-Ruedenberg and Boys schemes produce bent banana bonds. Similarly, for planar molecules which contain lone pairs (like water), the Pipek-Mezey method produces one in-plane cr-type lone pair and one out-of-plane yr-type lone pair, while the Edmiston-Ruedenberg and Boys schemes produce two equivalent rabbit ear lone pairs. [Pg.228]

Here are three schemes, in each of which the second step must be very rapid compared to the first for it to correspond to the data ... [Pg.132]

The plan, then, was to do the next 20 analyses according to a modified protocol that incorporated a weighing step after every volumetric operation. The evaluation of the absorbance measurements (data files VVV.dat, VWV.dat, and WWW.dat) was carried out according to three schemes for the aforementioned steps 2 to 4, to use either the volumetric or the gravimetric results, or use a combination thereof ... [Pg.176]

Figure 4.1. Assay results calculated according to three schemes WWW (top), VWV (middle), and VVV (bottom). The raw values (top panel, scale +2%) are plotted chronologically. In the bottom panel the standard deviations for the triplicate determinations are shown (scale 1%) the bold bar at right signals the average within-group SD, and the thin line besides it the overall SD. The VVV scheme does look inferior in this metric, but the raw data graph is much more powerful in conveying the idea. Figure 4.1. Assay results calculated according to three schemes WWW (top), VWV (middle), and VVV (bottom). The raw values (top panel, scale +2%) are plotted chronologically. In the bottom panel the standard deviations for the triplicate determinations are shown (scale 1%) the bold bar at right signals the average within-group SD, and the thin line besides it the overall SD. The VVV scheme does look inferior in this metric, but the raw data graph is much more powerful in conveying the idea.
The first criterion among others is the number of the iterations in the following three schemes ... [Pg.689]

There are conjectures that the above three schemes may be quickly fixed by running a pseudo random generator through a live data scheme twice, where the later run will clear all the effects of the earlier one. This may make the non-functional CLBs that were used as the pseudo-random generator appear functional. While this heuristics is interesting, we will show later in the appendix that it does not work for this case. It may not be a trivial task to fix these schemes. [Pg.11]

Both possibilities are shown. Scheme P is a strong homomorphic image of each of the two resulting schemes all three schemes are strongly equivalent. [Pg.96]

Second-order and third-order results often bracket the true correction to pF - Three schemes that scale the third-order terms in various ways are known as the Outer Valence Green s Function (OVGF) [8], In OVGF calculations, one of these three recipes is chosen as the recommended one according to rules based on numerical criteria. These criteria involve quantities that are derived from ratios of various constituent terms of the self-energy matrix elements. Average absolute errors for closed-shell molecules are somewhat larger than for P3 [31]. [Pg.139]

The controllability analysis was conducted in two parts. The theoretical control properties of the three schemes were first predicted through the use of the singular value decomposition (SVD) technique, and then closed-loop dynamic simulations were conducted to analyze the control behavior of each system and to compare those results with the theoretical predictions provided by SVD. [Pg.62]

Perform a retrosynthetic analysis for each of the following molecules. Develop at least three outline schemes. Discuss the relative merits of the three schemes, and develop a fully elaborated synthetic plan for the one you consider to be most promising. [Pg.920]

Procaine can be prepared by one of three main routes, the basic pathways of which are illustrated in the three Schemes which follow [1-4,11]. [Pg.400]

The ground and excited state matrix Hartree-Fock energies for the He, Li and Be atoms are presented in Tables 1, 2 and 3, respectively. All energies are given in atomic units, (Hartree). In each of these tables, we label the columns according to the three schemes, (a), (b) and (c), described above for generating sequences of even-tempered basis sets. We consider each system in turn. [Pg.117]

Hydrolase-catalyzed acylation can be used to purify a diastereo- and enantiomerically enriched product. For example dimethylzinc addition to the racemic aldehyde 77 furnishes the racemic phenylsulfanylbutanol 78 (Scheme 4.29) in a 95/5 (2R, 3R )/(2R, 3S )-mtio. When this is treated with Chirazyme L2 (CALB) and vinyl acetate in heptane it is resolved with a high E-value (>400) [91]. However the diastereomeric ratio in the remaining substrate and produced ester is virtually unchanged. To circumvent the problematic contamination with the undesired diastereomers, enantiomerically enriched aldehyde 77 was reacted with dimethyl-zinc to furnish one major stereoisomer of 78 contaminated with a small amount of a mixture of the other three (Scheme 4.29). Because the two major contaminants had the opposite configuration at position 2 relative to the major product, these contaminants were efficiently removed from the major product and the trace byproduct by treatment with the 2R-selective Chirazyme L2 (CALB) and vinyl acetate in heptane to furnish virtually diastereo- and enantiomerically pure acetate (2R,3R)-79 or the alcohol (2S,3S)-78 (Scheme 4.29) [91]. [Pg.95]

It is immediately apparent that only the 2E states of HRe(CO)5 are split by spin—orbit coupling. However, it is also obvious that subsequent interactions can take place between MOs of the same (E or E") symmetry. Considering only the predominantly metals orbitals, Hall (161) has presented three schemes that differ in the relative energies of the b2 and e MOs. [Pg.64]

A-7. Synthesis of the following alcohol is possible by three schemes using Grignard reagents. Give the reagents necessary to carry out each of them. [Pg.361]

In this section, we describe counterfeiting attacks for the three schemes described in the previous section. We also provide experimental results demonstrating the plausibility of such attacks. [Pg.11]

Although we have examined three particular instances of block-wise independent oblivious watermarking schemes in this paper, we would like to again note that these three schemes merely served as examples of this class of techniques, and were selected to demonstrate the plausibility of the counterfeiting attacks that we propose in this paper based on the ease of implementation by which the attacks could be carried out. Other oblivious watermarking techniques have been reported in the literature [3, 8, 4] that display the same block-wise independence property that we exploit, and hence could potentially be vulnerable to attacks similar to those proposed in this paper. [Pg.21]

In order to compare the economics as well as the overall C02 emissions from each schematic studied in this joint venture, a reference case was analyzed. The reference case included only the process steps associated with coal gasification, shift, and hydrogen purification, but none of the steps associated with C02 sequestration or coalbed methane recovery. Three other process schemes were examined in this study and compared to the reference case. Figure 1 depicts simplified process flow diagrams for the reference case and the other three schemes (note the overall heat integration for each scheme is not shown). The top portion of the figure shows the process steps that are the same for each scheme up to hydrogen purification, while the operations inside the dashed boxes represent the steps that differ between the four cases. [Pg.19]

It is not always necessary to apply all the three schemes (a)- (c) in the Principles of Sect. 5.3 in order to achieve a complete generation of the C HS benzenoid isomers, even if all three formulas C 3HS 1, C 4HS 2 and C 2HS exist. These features are easily accounted for if the pictures of all benzenoids with the formula C HS are available two comprehensive collections [8, 43] may be consulted for numerous examples. If all the systems with the formula C HS have a P2-mode... [Pg.78]

As a corollary of this proposition such a benzenoid can only be generated by scheme (c) out of the three schemes in Principles of Sect. 5.3. [Pg.89]

A memorandum of January 5,1947 (from J. S. Rearick to Rubin) described three schemes under consideration for use in the pilot plant ... [Pg.7]

Nanostructure-based LSPR biosensing has been classified into three schemes surface-relief nanostructures, surface-relief nanostructures coupled to nanoparticles, and nanoparticles. These schemes share many aspects of plasmon characteristics in common, such as shape and concentration dependence. Local field enhancement as a result of plasmon excitation can be used for highly sensitive biosensing. Given particular bio-sensing applications, one of these schemes can be selected to meet... [Pg.205]

We performed experimental research on stability assessment of RVX and identification of its transformation products under the action of equimolar or excess amoimts of water. The method for analysis was GC-EIMS. In a dilute aqueous solution (lOmg/ml) in the presence of 5% phosphoric acid, the concentration of RVX after exposiue for 20 days at room temperature without stirring was 2.7 mg/ml or 27% of the initial amoimt. Since among RVX hydrolysis products both volatile and nonvolatile compounds could be expected, we ehose three schemes for sample preparation ... [Pg.70]

On the other hand, the highest occupied eigenvalues which reflect the asymptotic form of the density, and thus even in the x-only limit should be close to the ionisation potential, are too small by roughly 50% for the DFS and RLDA and by 30- % for the RWDA . Thus while the latter improves on the asymptotic form of in principle, the effect of this formal improvement on the physically relevant part of the asymptotic regime is rather limited. Note further, that for Yb all three schemes incorrectly predict the 4F7/2-orbital to be most weakly bound instead of the 6S1/2-orbital. The same deficiency has been observed for Cr and Cu in the nonrelativistic case [59]. These difficulties to reproduce the size and the ordering of the outermost eigenvalues are well known from the nonrelativistic case and are not related to the relativistic corrections in Ex [n]-... [Pg.38]

There is little experience with the von Niessen method, but for most molecules the remaining three schemes tend to give very similar LMOs, The main exception is systems... [Pg.122]

For all the three schemes of ECM, the direct problems are solved in a similar way. The solutions of the inverse problem are known only for the first scheme, because for the other ECM schemes, the shape and dimensions of the machined surface do not enable one to determine, uniquely, the shape of the TE working surface. [Pg.826]

The first three schemes are amenable to field observation and decision, whereas the latter two require further chemical and isotopic measurements. This chapter reviews these classifications and concludes by offering some end-member classes of terrestrial evaporites that unify the field and chemical aspects. Indeed, there is a sound geological and geomorphological basis for the broad range of chemical and isotopic differences within evaporites. [Pg.332]

To be acceptable, a calculation procedure must be stable, and the amount of truncation error introduced must be the one required. In this subsection, we evaluate the stability condition of each of the finite difference calculation procedures described above, and we determine the amount of truncation error done with each of these schemes. However, because of the great difficulty of these theoretical studies when handling the nonlinear case, we limit this discussion of the stability condition and the truncation error made with the three schemes we have described to the case of a linear isotherm. [Pg.500]

Czok and Guiochon [49] called these three schemes Methods I, II, and HI, respectively. They discussed their physical sense and their consequences for the calculation of numerical solutions of the single and multicomponent problems. [Pg.503]


See other pages where Three scheme is mentioned: [Pg.214]    [Pg.11]    [Pg.1]    [Pg.3]    [Pg.3]    [Pg.3]    [Pg.299]    [Pg.7]    [Pg.520]    [Pg.355]    [Pg.376]    [Pg.104]    [Pg.81]    [Pg.129]    [Pg.127]    [Pg.68]    [Pg.35]   
See also in sourсe #XX -- [ Pg.1072 ]




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Classes of stable three-layer schemes

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