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Etheric channels

The electrocrystallization and characterization of a novel molecular metal which displays both electronic and ionic conduction has been reported. The complex Li0.6(15-crown-5-ether)[Ni-(dmit)2] H20 is composed of stacks of [Ni(dmit)2] units which provide pathways for electronic conduction. The stacks are separated by parallel stacks of 15-crown-5-ether moieties in a channellike formation which facilitates ion conduction. The salt has a room temperature conductivity of 240 Scm-1. Temperature-dependent magnetic susceptibility and NMR measurements were used to prove the existence of Li+ movement within the crown ether channels.1030... [Pg.339]

Only after the Paths have been walked do practitioners come to those secret paths of the Tree that have, until now, been veiled in secrecy. These are the Paths of Concealed Glory, sometimes called the Invisible Paths. They are so called because, until practitioners have grasped the First Matter, they are difficult to perceive. These so-called Secret Paths of the Tree are the multitudinous nadis or etheric channels that permeate the subtle bodies anatomy, described in yoga. The same concept is found in the meridians of acupuncture. Macrocosmically, they are the ley lines that unite centers of energy upon our planet and the beams of energy that join each star to every other star in existence. The secret paths are the threads, of the Web of Being. [Pg.189]

The diffusion, location and interactions of guests in zeolite frameworks has been studied by in-situ Raman spectroscopy and Raman microscopy. For example, the location and orientation of crown ethers used as templates in the synthesis of faujasite polymorphs has been studied in the framework they helped to form [4.297]. Polarized Raman spectra of p-nitroaniline molecules adsorbed in the channels of AIPO4-5 molecular sieves revealed their physical state and orientation - molecules within the channels formed either a phase of head-to-tail chains similar to that in the solid crystalline substance, with a characteristic 0J3 band at 1282 cm , or a second phase, which is characterized by a similarly strong band around 1295 cm . This second phase consisted of weakly interacting molecules in a pseudo-quinonoid state similar to that of molten p-nitroaniline [4.298]. [Pg.262]

Shaker-channels, eag (ether- -go-go)-channels, slo (slow-poke)-channels were cloned from behavioral Drosophila melanogaster mutants. The channels were named according to the Drosophila mutant phenotype, Shaker, ether-go-go, slow-poke. Subsequently, eag-cDNA was used to clone related voltage-gated potassium channel subunits erg (eag-related) and elk (eag-like). The human erg ortholog (HERG) mediates cardiac DCS. [Pg.1131]

Kang J, Chen XL, Wang H, et al Interactions of the narcotic 1-alpha-acetylmethadol with human cardiac K+ channels. Eur J Pharmacol 458 25-29, 2003 Katchman AN, McGroary KA, Kilborn MJ, et al Influence of opioid agonists on cardiac human ether-a-go-go-related gene K(+) currents. J Pharmacol Exp Ther 303 688-694, 2002... [Pg.101]

CoMSIA (comparative molecular similarity index analysis) is a recent development from CoMFA and does not suffer from the alignment problem. It has been used to model hERG potassium channel inhibition by drugs [59] and the toxicity of phenylsulfonyl carboxylates [60], organophosphates [61], and polybrominated diphenyl ethers [62], with results comparable to those from CoMFA. [Pg.481]

The unreacted ethanol and the diethylether product retained >98% of from the starting 0-ethanol, indicating that no isotope scrambling occurred. Data in Table 4 demonstrate that was retained in the mixed ether and ethanol attack of the acid-activated 2-pentanol via an axial S 2 rear-attack was the predominant synthesis pathway. Evidently, the shape selectivity induced by the 2 M-5 zeolite channel structure (Figure 2) plays an important role in achieving the remarkably higher configuration inversion... [Pg.607]

Conclusive evidence has been presented that surface-catalyzed coupling of alcohols to ethers proceeds predominantly the S 2 pathway, in which product composition, oxygen retention, and chiral inversion is controlled 1 "competitive double parkir of reactant alcohols or by transition state shape selectivity. These two features afforded by the use of solid add catalysts result in selectivities that are superior to solution reactions. High resolution XPS data demonstrate that Brpnsted add centers activate the alcohols for ether synthesis over sulfonic add resins, and the reaction conditions in zeolites indicate that Brpnsted adds are active centers therein, too. Two different shape-selectivity effects on the alcohol coupling pathway were observed herein transition-state constraint in HZSM-5 and reactant approach constraint in H-mordenite. None of these effects is a molecular sieving of the reactant molecules in the main zeolite channels, as both methanol and isobutanol have dimensions smaller than the main channel diameters in ZSM-S and mordenite. [Pg.610]

Reducing the processing time is a driver for micro channel processing of aldol reactions [15]. Using reactive reactants such silyl enol ethers, this can be accomplished. [Pg.528]

Lehn 242 243) has described a solid phase model of a K+ channel based on the crown ether 37. The crystal structure of this inclusion complex reveals stacking of the crown ethers into vertical columns, empirical formula [2 37,2 K, 3 H20]2+, linked by water and potassium ions. The counter ions, empirical formula [K, 3 Br, 4 H20]2, comprise a polymeric chain running parallel to the columns. [Pg.189]


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See also in sourсe #XX -- [ Pg.189 ]




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