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71.
Sami M. Hamye 《Semigroup Forum》1986,34(1):341-357
Let S be a semitopological semgroup and let Cb (S) denote the B*-algebra of all continuous bounded complex-valued functions on S. In this paper, we consider a left m-introverted and translation
invariant B*-subalgebra F of Cb(S) containing the constant functions. Our concern is with ΔF, the maximal ideal space of F up to an isomorphic homeomorphism,
when it is made into a compact right topological semigroup containing a dense continous homomorphic image of S under the Gelfand
topology and a suitably chosen binary operation. We establish a representation of the closed left ideals of ΔF and study its
centre and ideal structure in some special cases. 相似文献
72.
We introduce a general method in order to construct the nonchiral fusion rules which determine the operator content of the operator product algebra for rational conformal field theories. We are particularly interested in the models of the complementary D-like solutions of the modular invariant partition functions with cyclic center Z
N
. We find that the nonchiral fusion rules have a Z
N
-grading structure. 相似文献
73.
74.
We calculate the energy eigenvalues and the sate functions of one-electron Quantum Dot (QD) by using a combination of Quantum Genetic Algorithm (QGA) and Hartre-Fock-Roothaan (HFR) method. The linear and the third-order nonlinear optical absorption coefficients for the 1s-1p, 1p-1d, and 1d-1f transitions are examined as a function of the incident photon energy for three different values of the stoichiometric ratio. The results show that the stoichiometric ratio, impurity, relaxation time, and dot size have great influence on the optical absorption coefficients of QDs. 相似文献
75.
The present study examines the absorption of a laser beam at different wavelengths by a partially-ionized vapour during the
interaction mechanism. The applicability of the theoretical models developed is discussed in detail. The interaction of the
high- and low-power intensities of a laser beam with plasma is distinguished. It is shown that different metal vapours at
similar temperatures and densities have absorption depths which may differ by an order of magnitude. Even more substantial
is the difference between the absorption depths of light from different lasers in common use. It is also shown that the free
electron temperature becomes significantly different from the heavy particle temperature for power intensities above the critical
level which is typically > 1014W/m2. The free electron velocity distribution has an isotropic part which becomes non-Maxwellian for power intensities greater
than the critical power intensity. 相似文献
76.
Orhan
elli Salih Erzeneo
lu Bekir Gürbulak 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,90(3-4):399-407
Measurements have been made to determine the mass attenuation coefficients of undoped n-type InSe, and Gd, Ho, Er doped n-InSe single crystals using a Si(Li) detector in the energy region 15.746–40.930 keV X-ray energies with energy dispersive X-ray fluorescence systems. InSe, InSe:Gd, InSe:Ho and InSe:Er single crystals were grown by using the stockbarger method. The measured values are graphically compared with the theoretical ones obtained using WinXcom. 相似文献
77.
Mirabegron is a novel β3-adrenoceptor agonist containing an amide group. It was subjected to stress conditions of acidic and alkaline hydrolyses. The hydrolytic degradation product was isolated and its structure was confirmed using mass and IR spectrometry. Two stability-indicating chromatographic methods have been proposed for the determination of mirabegron. TLC method was applied using silica gel as stationary phase and chloroform–methanol–ammonia (9.0:1.0:0.1 by volume) as the mobile phase, and chromatograms were scanned at 250 nm. Accurate determination of the drug was achieved over the concentration range of 2–12 μg per band. In addition, an isocratic HPLC method was developed on Agilent C18 column (150 mm × 4.5 mm I.D., particle size 5 µm) using ethanol-phosphate buffer pH 2.5 (30:70, by volume) as a mobile phase with flow rate of 1 mL min?1.The intact drug was detected at 250 nm with running time less than 5 min. Mirabegron was determined accurately in a concentration range of 1–25 µg mL?1. The proposed chromatographic methods were applied successfully for the assay of mirabegron in pharmaceutical dosage form and both methods were validated as per the International Conference on Harmonization guidelines and statistically compared with a reported gradient HPLC method. 相似文献
78.
Ponnusamy Sami Kandasamy Venkateshwari Natarajan Mariselvi Arunachalam Sarathi Kasi Rajasekaran 《Transition Metal Chemistry》2010,35(2):137-142
l-cysteine undergoes facile electron transfer with heteropoly 10-tungstodivanadophosphate,
[ \textPV\textV \textV\textV \textW 1 0 \textO 4 0 ]5 - , \left[ {{\text{PV}}^{\text{V}} {\text{V}}^{\text{V}} {\text{W}}_{ 1 0} {\text{O}}_{ 4 0} } \right]^{5 - } , at ambient temperature in aqueous acid medium. The stoichiometric ratio of [cysteine]/[oxidant] is 2.0. The products of the
reaction are cystine and two electron-reduced heteropoly blue, [PVIVVIVW10O40]7−. The rates of the electron transfer reaction were measured spectrophotometrically in acetate–acetic acid buffers at 25 °C.
The orders of the reaction with respect to both [cysteine] and [oxidant] are unity, and the reaction exhibits simple second-order
kinetics at constant pH. The pH-rate profile indicates the participation of deprotonated cysteine in the reaction. The reaction
proceeds through an outer-sphere mechanism. For the dianion −SCH2CH(NH3
+)COO−, the rate constant for the cross electron transfer reaction is 96 M−1s−1 at 25 °C. The self-exchange rate constant for the
- \textSCH2 \textCH( \textNH3 + )\textCOO - \mathord