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Final coupling analysis

Density functional theory, direct molecular dynamics, complete active space self-consistent field (CASSCF) technique, non-adiabatic systems, 404-411 Density operator, direct molecular dynamics, adiabatic systems, 375-377 Derivative couplings conical intersections, 569-570 direct molecular dynamics, vibronic coupling, conical intersections, 386-389 Determinantal wave function, electron nuclear dynamics (END), molecular systems, final-state analysis, 342-349 Diabatic representation ... [Pg.74]

This same analysis is then performed for the energy balance for the gas, the energy balance for the thermal well, the two mass balances, and the continuity equation. The final coupled system of algebraic and differential equations consists of 5N ordinary differential equations and N + 6(NE + 1) algebraic equations, where... [Pg.156]

On-Line Systems Flowing MMLLE systems have been established in different layouts with automation and on-line hyphenation to GC and HPLC analysis. An automated on-line FS-MMLLE-GC system with a loop-type interface compatible with LVI was used for the extraction of pesticides and PAHs in surface waters.86 In another study, pressurized hot water extraction (PH WE) was coupled on-line to a FS-MMLLE-GC-FID system and applied to the analysis of PAHs in soil, where MMLLE was used as a cleanup and concentration step of the PH WE extract prior to final GC analysis.87 In addition, an HF-MMLLE setup was incorporated in PHWE and GC, resulting in an online PHWE-HF-MMLLE-GC system, where the HF membrane module contained 10-100 HFs. The system served for the extraction and analysis of PAHs in soil and sediments ... [Pg.84]

The book s illustrative examples are all taken from the pharmaceutical sciences, so students (and staff) in the areas of pharmacy, pharmacology and pharmaceutical science should feel at home with all the material. However, the issues considered are of concern in most scientific disciplines and should be perfectly clear to anybody from a similar discipline, even if the examples are not immediately familiar. Material is arranged in a developmental manner. Initial chapters are aimed at level 1 students this material is fairly basic, with special emphasis on random sampling error. The next section then covers key concepts that may be introduced at levels 1 or 2. The final couple of chapters are most likely to be useful during final year research projects These include one on questionnaire design and analysis. [Pg.305]

X-ray crystallographic analysis of two complexes, 87a 1 and 87c l, before and after irradiation, were performed at low temperature (— 170°C). Fortunately, these reactions were revealed to proceed via a single crystal-to-single crystal transformation without decomposition of the initial crystal structures. Furthermore, the reaction pathway was successfully traced by x-ray analyses of crystals irradiated for different times up to 67 days. These revealed that the ketyl group rotated around the C(ketyl)-C5 (phenyl) bond and finally coupled with the steroid C5 position to produce the adduct. [Pg.508]

For each point in the (Ro, Rm) plane, the corresponding structure is analyzed both approximately, with a decoupled analysis, and exactly, with a coupled analysis. Thus, the decoupling error is calculated for all points of the (R(o, Rm) plane, i.e., for the chosen wide range of dynamic characteristics of the irregular structures, as described in Eq. 4 for all levels of the structure. Three reference error levels are chosen, namely, 10 %, 20 %, and 30 %, and the points of the (R, Rm) plane at which these error levels appear are noted. Finally, the envelope of these points is plotted in a set of curves named decoupling curves, one for each error level, as... [Pg.1494]

Some final comments on the relevance of non-adiabatic coupling matrix elements to the nature of the vector potential a are in order. The above analysis of the implications of the Aharonov coupling scheme for the single-surface nuclear dynamics shows that the off-diagonal operator A provides nonzero contiibutions only via the term (n A n). There are therefore no necessary contributions to a from the non-adiabatic coupling. However, as discussed earlier, in Section IV [see Eqs. (34)-(36)] in the context of the x e Jahn-Teller model, the phase choice t / = —4>/2 coupled with the identity... [Pg.28]

In order to reduce or eliminate off-line sample preparation, multidimensional chromatographic techniques have been employed in these difficult analyses. LC-GC has been employed in numerous applications that involve the analysis of poisonous compounds or metabolites from biological matrices such as fats and tissues, while GC-GC has been employed for complex samples, such as arson propellants and for samples in which special selectivity, such as chiral recognition, is required. Other techniques include on-line sample preparation methods, such as supercritical fluid extraction (SFE)-GC and LC-GC-GC. In many of these applications, the chromatographic method is coupled to mass spectrometry or another spectrometiic detector for final confirmation of the analyte identity, as required by many courts of law. [Pg.407]

The dipyrrylacelylenedicarbaldehyde 18, which already contains, along with the acetylene moiety, two of the two-carbon bridges of the final macrotetracycle, can be prepared by a Heck-type coupling of 5-iodopyrrole-2-carbaldehydes with acetylene.8a,b The main conjugation pathway with 22n electrons is already present in the acetylene-cumulate systems 19. The expected planarity of this chromophore has been confirmed by X-ray structure analysis.8a b... [Pg.694]

From the study of the influencing of single reactions by products and by other added substances and from the analysis of mutual influencing of reactions in coupled systems, the following conclusions can be drawn concerning adsorption of the reaction components. (1) With the exception of crotyl alcohol on the platinum-iron-silica gel catalyst, all the substances present in the coupled system, i.e. reactants, intermediate products, and final products, always adsorbed on the same sites of the catalytic surface (competitive adsorption). This nonspecificity was established also in our other studies (see Section IV.F.2) and was stated also by, for example, Smith and Prater (32), (2) The adsorption of starting reactants and the desorption of the intermediate and final products appeared in our studies always as faster, relative to the rate of chemical transformations of adsorbed substances on the surface of the catalyst. [Pg.49]


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See also in sourсe #XX -- [ Pg.125 ]




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Final coupling

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