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Nelson class

To summarize, we have considered a quantum mechanical N-body system with dilation analytic potentials, Ey, and its dependence on the scaling parameter i] = t] (for some 0 < < 0, depending on V). To be more detailed, we need to restrict Hilbert space to a dense subspace [54], the so-called Nelson class N, which provides the domain over which the unbounded complex scaling is well-defined. Closing the subset < - D T) in ft, see [9] and references therein for a more detailed expose, one obtains the scaled version of the original partial differential equation... [Pg.97]

The mathematicians have concentrated their interest on the transformed Hamiltonian for a single particle in one dimension, and they have solved the problem of the domain changes by the introduction of the Nelson class (16), which contains all functions on which the operator v(9) = e,9A, given by Eq. (3.17), is analytically defined for all complex 9. Even if a great deal of strict mathematical work is now devoted to the problem of a single particle in three dimensions, it will probably take a fair amount of time until all the fundamental theorems have been strictly proved for IV-electron systems. [Pg.129]

Recapitulating, the first step consists of restricting the Hilbert space to a smaller domain 0 for which the scaling U is defined for all complex q values with its arguments smaller in absolute value than i o- The second step, after the parameter has been made complex (r —> i t ), consists of completing the Nelson class of dilation analytic vectors to the domain of H or in this case T. Here this means convergence with respect to the standard norm (for both the functions and its first and second partial derivatives). [Pg.13]

The Nelson class yacht Teneriffe, designed by Uffa Fox and built by Pochin s (Manchester) Ltd, used adhesively laminated wood for keel, stem, ribs, bilge strings and gunwale. The planking was also bonded to the ribs with a resorcinol-formaldehyde wood adhesive (Aerodux 185, Ciba-Geigy). [Pg.282]

Attempts to synthesize transition metal alkyl compounds have been continuous since 1952 when Herman and Nelson (1) reported the preparation of the compound C H6>Ti(OPri)3 in which the phenyl group was sigma bonded to the metal. This led to the synthesis by Piper and Wilkinson (2) of (jr-Cpd)2 Ti (CH3)2 in 1956 and a large number of compounds of titanium with a wide variety of ligands such as ir-Cpd, CO, pyridine, halogen, etc., all of which were inactive for polymerization. An important development was the synthesis of methyl titanium halides by Beerman and Bestian (3) and Ti(CH3)4 by Berthold and Groh (4). These compounds show weak activity for ethylene polymerization but are unstable at temperatures above — 70°C. At these temperatures polymerizations are difficult and irreproduceable and consequently the polymerization behavior of these compounds has been studied very little. In 1963 Wilke (5) described a new class of transition metal alkyl compounds—x-allyl complexes,... [Pg.264]

In vitro, fibril formation by several proteins displays an initial lag phase, followed by a rapid increase in aggregation (reviewed in Rochet and Lansbury, 2000). Introduction of fibrillar seeds eliminates the lag phase. These cooperative aggregation kinetics suggest that fibril formation begins with the formation of a nucleus and proceeds by fibril extension. The structure of the nucleus must therefore act as a template for the protein s conformation in the fibril. As the structural requirements for templating are unclear, it is difficult to assess the consistency of the model classes with this feature of fibril formation. We have described one possible templating mechanism for the cross-/ spine of GNNQQNY (Nelson et al., 2005). [Pg.270]

There have been excellent review articles related to the present topics (e.g. Muenchen and Pienta, 1999 Nelson et al, 2004, Inche and La Thangue, 2006). Our review has provided an overview of the research activities to understand the molecular basis of the function of the various classes of DNA-targeting drugs at... [Pg.179]

Venlafaxine and milnacipran are two members of a new class of antidepressants that have selective effects on the reuptake of both serotonin and noradrenaline—serotonin noradrenaline reuptake inhibitors (SNRIs). In theory, based on the findings of B. M. Baron and colleagues [1988 and of J. C. Nelson and colleagues (1991), the combination of these two pharmacological actions should be associated with superior efficacy either in terms of rapid onset of action or extra efficacy at the end of treatment. [Pg.208]

In an attempt to relate calculated results to experimental findings for monomeric, lignin model compounds, preliminary work has compared theoretically determined electron densities and chemical shifts reported from carbon-13 nuclear magnetic resonance spectroscopy (62). Although chemical shifts are a function of numerous factors, of which electron density is only one, both theoretical and empirical relationships of this nature have been explored for a variety of compound classes, and are reviewed by Ebra-heem and Webb (63), Martin et al. (64), Nelson and Williams (65), and Farnum (66). [Pg.275]

Fortunately, there is now a comprehensive body of knowledge on the metabolic reactions that produce reactive (toxic) intermediates, so the drug designer can be aware of what might occur, and take steps to circumvent the possibility. Nelson (1982) has reviewed the classes and structures of drugs whose toxicities have been linked to metabolic activation. Problem classes include aromatic and some heteroaromatic nitro compounds (which may be reduced to a reactive toxin), and aromatic amines and their N-acylated derivatives (which may be oxidized, before or after hydrolysis, to a toxic hydroxylamine or iminoquinone). These are the most common classes, but others are hydrazines and acyl-hydrazines, haloalkanes, thiols and thioureas, quinones, many alkenes and alkynes, benzenoid aromatics, fused polycyclic aromatic compounds, and electron-rich heteroaromatics such as furans, thiophenes and pyrroles. [Pg.93]

Nelson et al., 1997 Marco et al., 1998 Vazquez et al, 1997). Within this MIC range, there is a reproducible pattern of MIC by species that shows an overall rank order of C. albicans = C. tropicalis = C. glabrata < C. parap-silosis < C. krusei = C. lusitaniae (Marco et al., 1998 Vazquez et al, 1997). Recent clinical isolates demonstrate similar susceptibility as the defined type cultures (Pfaller et al., 1998 Rex et al., 1998a). MK-0911, like compounds in the echinocandin class, also has significantly lower MICs with AM3 against Candida species (Nelson et al., 1997). [Pg.458]

Diols have been rarely observed in insect cuticular lipids (Buckner, 1993). Odd-carbon-number diols (C23-C29) were the major lipid class (55%) of the larval cuticular lipids from the flour beetle, Tenebrio molitor (Bursell and Clements, 1967). The major diol constituent was 8, 9-pentacosanediol. For the cuticular lipids of M. sexta larvae, very small amounts (<1%) of 7,8- and 8,9-C27 diols and 8,9- and 9,10-C29 diols were identified (Espelie and Bernays, 1989). Hydroxy n-alkanols are diols with a hydroxyl functional group on the C, position (terminal) of the alkyl chain, but are technically not alcohol derivatives of hydrocarbons. There are a few reports of the occurrence of insect hydroxy -alkanols (Buckner, 1993 Nelson and Blomquist, 1995 Buckner et al., 1996). In a structure analysis study of beeswax, the major alcohol moieties of the diester fraction were identified as 1,23-tetracosanediol (42.2%), 1,27-octacosanediol (26.0%) and 1,25-hexacosanediol (20.2%) (Tulloch, 1971). The hydroxy n-alkanols comprised 16% of the cuticular lipids of FI. zea pupae and were identified as C30-C36 even-chain n-alcohols with hydroxyl groups on carbon numbers 11, 12, 13, 14, or 15 (Buckner et al., 1996). Mass spectral analysis indicated the presence of unsaturation in the alkyl chain of the major diol components. [Pg.189]

Very-long-chain methyl-branched alcohols (C38 to >C44) and their esters with short-chain acids (C2 to C5) represent a novel class of long-chain internal lipids which mainly occur during insect metamorphosis (Nelson, 1993). The very-long-chain methyl-branched alcohols were first characterized in the internal lipids of developing pupae (pharate adults)... [Pg.189]

Nelson A (2005) Product class 7 ynones. In Cossy J (ed) Science of synthesis, vol 26. Georg Thieme, Stuttgart, pp 971-988... [Pg.81]

Like other dissolved organic nutrients, the chemical composition of organic P is relatively unknown. Marine dissolved organic phosphorus (DOP) composition has been mostly identified as particular compound classes such as monophosphate esters, phosphonucleotides, nucleic acids, phospholipids, phosphonates and polyphosphates (Benitez-Nelson, 2000). Kolowith et al. (2001) found that monophosphate esters and phosphonates are major components in the Pacific Ocean, the Atlantic Ocean and the North Sea. ATP (adenosine triphosphate), ubiquitous in aU living cells, has been used as a model DOP compound in radiotracer experiments to obtain information on P sources and fluxes in natural environments (Bjorkman et al., 2000 Karl and Bossard, 1985) and cyanobacterial cultures (Fu et al., 2006). [Pg.1642]

Acyl Lipids The composition of nonpolar acyl lipids in WGO was reported by Bames (2). Triacylglycerols are the major lipid class in WGO (Table 5). According to Nelson et al. (31), about 30% of the TAG consists of l-palmito-2,3-dilmolem. Trilinolein ( 16%) and l-palmito-2-linoleo-3-olein ( 12%) are the two other major TAGs present in WGO. Details on distribution of specific fatty acids in the TAG of WGO are discussed by Bames (2) and Nelson et al. (31). [Pg.1562]

Holt, P.G., Haining, S., Nelson, D.J. and Sedgwick, J.D. (1994). Origin and steady-state of class II MHC-bearing dendritic cells in the epithelium of the conducting airways. J. Immunol. 153, 256-261. [Pg.11]


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See also in sourсe #XX -- [ Pg.97 ]

See also in sourсe #XX -- [ Pg.129 ]




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