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Theory partial resolution

Simple one-dimensional electrophoretic separation techniques can only partially resolve the complex mixtures of proteins and peptides found in biological fluids. Resolution may be improved by combining an electrophoretic separation with a second separation method at right angles. The second method will preferably be based on a different analytical principle. In theory, the resolution of such combinations is the product of the resolution of the component methods. [Pg.268]

The three-step model was developed as a consequence of the extreme complexity of a PBC system. This author had a wish to describe the PBC-process as simple as possible and to define the main objectives of a PBC system. The main objectives of a PBC system are indicated by the efficiencies of each unit operation, that is, the conversion efficiency, the combustion efficiency, and the boiler efficiency. The advantage of the three-step model, as with any steady-state system theory, is that it presents a clear overview of the major objectives and relationships between main process flows of a PBC system. The disadvantage of a system theory is the low resolution, that is, the physical quantity of interest cannot be differentiated with respect to time and space. A partial differential theory of each subsystem is required to obtain higher resolution. However, a steady-state approach is often good enough. [Pg.41]

Kinetic resolution of chiral aUylic alcohols.7 Partial (at least 60% conversion) asymmetric epoxidation can be used for kinetic resolution of chiral allylic alcohols, particularly of secondary allylic alcohols in which chirality resides at the carbinol carbon such as 1, drawn in accordance with the usual enantioface selection rule (Scheme I). (S)-l undergoes asymmetric epoxidation with L-diisopropyl tartrate (DIPT) 104 times faster than (R)-l. The optical purity of the recovered allylic alcohol after kinetic resolution carried to 60% conversion is often > 90%. In theory, any degree of enantiomeric purity is attainable by use of higher conversions. Secondary allylic alcohols generally conform to the reactivity pattern of 1 the (Z)-allylic alcohols are less satisfactory substrates, particularly those substituted at the /1-vinyl position by a bulky substituent. [Pg.52]

For a general theory of kinetic resolution with a partially resolved chiral auxiliary, see Ref. 84. [Pg.296]

A recent development in ab initio quantum theory has been the introduction of (partially) numerical schemes for dealing with the two-electron integrals in a way that reduces the scaling with the size of the system. One of these is the pseudospectral (PS) [12, 13] technique, which is closely related to another procedure known as resolution of the identity (RI) [14-16]. The use of these schemes in conjunction with the LSA has been discussed in detail elsewhere [17]. Here we present just the basic idea behind the PS approach. [Pg.153]

In the language of dissonance theory, the cognition that "someone else has Z" is neither consonant nor dissonant with the two premises. It is simply irrelevant and thus cannot contribute anything to the resolution of inner conflict.92 One could argue, perhaps, that the displacement process is a "blindly" causal mechanism and that there is no presumption that it will solve, even partially and temporarily, the conflict that causes it. That would be, however, to go against the grain of all writings on the defense mechanisms from Freud onward. "The... [Pg.382]

Except for the fullerenes, carbon nanotubes, nanohoms, and schwarzites, porous carbons are usually disordered materials, and cannot at present be completely characterized experimentally. Methods such as X-ray and neutron scattering and high-resolution transmission electron microscopy (HRTEM) give partial structural information, but are not yet able to provide a complete description of the atomic structure. Nevertheless, atomistic models of carbons are needed in order to interpret experimental characterization data (adsorption isotherms, heats of adsorption, etc.). They are also a necessary ingredient of any theory or molecular simulation for the prediction of the behavior of adsorbed phases within carbons - including diffusion, adsorption, heat effects, phase transitions, and chemical reactivity. [Pg.103]

Clearly, in the subsystem resolution one could also consider all intermediate specifications of the molecular (constrained) equilibria, when only a part of the subsystems remains externally open (characterized by the fixed chemical potentials of a common reservoir) with the remaining, complementary set of subsystems being closed (characterized by the fixed subsystem numbers of electrons) [4,5]. Such mixed representations can be also naturally defined in the CSA approach. We would like to observe, that in the theory of chemical reactivity these partially opened situations do indeed arise, e.g., in the surface reactions, when one adsorbate is opened (chemisorbed) while the other reactant remains externally closed (physisorbed) on the catalyst surface, which acts as the electron reservoir for the reaction. [Pg.146]

R 239 J. Jokisaari, NMR of Noble Gases Dissolved in Liquid Crystals , p. 109 R 230 C.L. Khetrapal and G.A.N. Gowda, NMR of Partially Ordered Solutes with Emphasis on Structure Determination , p. 137 R 231 C. Fares and J.H. Davis, The Search for High-Resolution NMR Methods for Membrane Peptide Structure , p. 191 R 232 E.E. Burnell and C.A. De Lange, Solutes as Probes of Simplified Models of Orientational Order , p. 221 R 233 D.J. Photinos, Molecular Theory of Orientational Order , p. 259 R 234 G. Celebre and M. Longer , NMR Studies of Solutes in Liquid Crystals Small Flexible Molecules , p. 305 R 235 J.M. Poison, Simulations of Orientational Order of Solutes in Liquid Crystals , p. 325... [Pg.45]


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