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Corresponding Quantities (corresponding + quantity)
Selected AbstractsStrings and D-branes in holographic backgroundsFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 7-8 2005D. Israël Abstract We review recent progress in the study of non-rational (boundary) conformal field theories and their applications to describe exact holographic backgrounds in superstring theory. We focus mainly on the example of the supersymmetric coset SL(2, ,)/U(1), corresponding to the two-dimensional black hole, and its dual N = 2 Liouville. In particular we discuss the modular properties of their characters, their partition function as well as the exact boundary states for their various D-branes. Then these results are used to construct the corresponding quantities in the CFT of the NS5-brane background, with applications to Little String Theories. [source] Bronchodilatory effects of the aqueous extract of Gynostemma pentaphyllum and gypenosides III and VIII in anaesthetized guinea-pigsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2005Clara Circosta The bronchodilatory activity of the aqueous extract of Gynostemma pentaphyllum Makino leaves was investigated in anaesthetized guinea-pigs and compared with two of its isolated gypenosides (III and VIII). The results showed that the intravenous administration of the decoction of G. pentaphyllum (2.5, 5 or 10 mg kg,1) decreased bronchial resistance in basal conditions and significantly (P<0.01) reduced (68% inhibition) the bronchoconstrictor action of histamine. Furthermore, the extract antagonized (80% inhibition) the bronchoconstrictor response induced by the antigen in sensitized guinea-pigs. Gypenosides III (0.7 mg kg,1, i.v.) and VIII (0.3 mg kg,1, i.v.) caused a similar protective effect in both experimental models used; however, the duration and the intensity of the action was less than that of the extract containing corresponding quantities of gypenosides III and VIII. This study confirmed the validity of the traditional use of this plant in the treatment of asthma and other respiratory disorders. [source] Raman and infrared spectra, conformational stability, ab initio calculations and vibrational assignment of dimethylsilylisocyanateJOURNAL OF RAMAN SPECTROSCOPY, Issue 3 2010Gamil A. Guirgis Abstract The Raman (3200-30 cm,1) and/or infrared spectra (3500 to 400 cm,1) of gaseous, liquid and solid dimethylsilylisocyanate, (CH3)2 Si(H)NCO, have been recorded. The MP2(full) calculations, employing a variety of basis sets with and without diffusion functions, have been used to predict the structural parameters, conformational stability, vibrational fundamental wavenumbers, Raman activities, depolarization values and infrared intensities to support the vibrational assignment. The low wavenumber Raman spectrum of the gas with a significant number of Q-branches for the SiNC(O) bend is consistent with an essentially linear SiNCO moiety. The ab initio calculations supported this conclusion as all possible orientations of the NCO moiety lead to nearly the same energy. This result is at variance with the conclusion from the electron diffraction study that the heavy atom skeleton was bent with an angle of 152(5)° with one stable cis conformer. It is believed that this reported angle difference from 180° is due to the shrinkage effect. The SiH distance of 1.486 Å has been obtained from the isolated SiH stretching wavenumber. From the adjustment of the ab initio MP2(full)/6-311+G(d,p) predicted structural parameters, a proposed structure is reported, which is expected to give rotational constants within a few megahertz of the actual ones. These experimental and theoretical results are compared with the corresponding quantities of similar molecules. Copyright © 2009 John Wiley & Sons, Ltd. [source] Topological resonance energy, bond resonance energy, and circuit resonance energyJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 1 2008Jun-ichi Aihara Abstract Circuit resonance energy (CRE) is a key quantity that links energetic and magnetic criteria of aromaticity for a polycyclic ,-system. Topological resonance energy (TRE) correlates well with the sum of CREs for an entire ,-system. We found that bond resonance energy (BRE), so far defined to estimate the degree of kinetic stability for a polycyclic ,-system, also correlates very well with the corresponding quantity defined with CREs. These findings justify the view that graph-theoretical quantities, such as TRE and BRE, can be used safely even though they rely on unrealistic reference structures. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||