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81.
Recently photon-added states that could be detected through the emission rather than the absorption of electromagnetic radiation have been actively explored and investigated. In this paper, we construct the photon-added power-law-potential coherent states (PA-PLPCSs) using generalized Heisenberg algebra. The Klauder minimal set of conditions required to obtain coherent states are satisfied. We study nonclassical effects associated with PA-PLCSs using the Mandel parameter and discuss some of their intriguing nonclassical behavior. These states have interesting significance and can be realized experimentally, exhibiting highly nonclassical behavior that depends on the degree of excitation and other parameters. Finally, we study the dynamics of entanglement and quantum discord for two-mode state within the framework of PLPCSs and show that the sudden death and sudden birth of correlations are due to the change and transfer of the correlation between one mode and its environment, using the monogamic relation between the entanglement and quantum discord.  相似文献   
82.
This work presents the characteristics of a high frequency ion source operating on a low energy, 150 keV accelerator. The latter is to be used as a neutron generator and its design is based on a theoretical analysis which shows that if the axial potential in an electrostatic electrode system is made to increase with four thirds the power of axial distance, inward electric forces will compensate space charge forces tending to blow up the beam. This results in a simplified acceleration tube much shorter and of higher gradient than the conventional acceleration columns. The ion source itself is an ordinary type using axial extraction of the beam, and its main properties investigated are the beam current and beam quality (or emittance). Dependence of the two on different parameters is investigated in a series of tests.  相似文献   
83.
J. Eid  G. Baret 《Journal of Non》2005,351(3):218-227
This paper focuses on a new sol-gel preparation method of Eu doped Y2O3 aerogels, for application in luminescence and their characterization. The preparation method is based on a sol-gel technique using metal salts, by controlling the hydrolysis of these precursors with an epoxide. The monoliths prepared in this manner are transparent in the visible radiation domain. They have a mesoporous texture, a specific surface area of ≈350 to 400 m2 g−1 and they are X-ray amorphous. The gel network could be clearly observed by Transmission Electron Microscopy and showed the presence of localized poorly crystalline nanodomains, with some Eu segregation. A first evaluation of the luminescence which they develop during crystallization, has been carried out as a function of the heat treatment schedule.  相似文献   
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Belal  Fathalla  Elbrashy  Amina  Eid  Manal  Nasr  Jenny Jeehan 《Chromatographia》2009,69(11):1201-1209

A simple, stability-indicating, reversed-phase liquid chromatographic method was developed for the determination of lacidipine in the presence of its degradation products. The analysis was carried out using a 150 mm × 4.6 mm i.d., 5 μm particle size Nucleodur MN-C18 column. Mobile phase containing a mixture of acetonitrile and 0.02 M phosphate buffer (70:30) at pH = 5.0 was pumped at a flow rate of 1 mL min−1 with UV-detection at 254 nm. The method showed good linearity in the range of 0.06–15 μg mL−1 with a limit of detection (S/N = 3) of 0.016 μg mL−1 (3.5 × 10−8 M). The suggested method was successfully applied for the analysis of lacidipine in bulk and in commercial tablets with average recoveries of 100.19 ± 0.81% and 100.05 ± 0.69%, respectively. The results were favorably compared to those obtained by a reference method. The suggested method was utilized to investigate the kinetics of alkaline, acidic, peroxide and photo-induced degradation of the drug. The apparent first-order rate constant, half-life times and activation energies of the degradation process were calculated. The pH profile curve was derived. The proposed method was successfully applied to the content uniformity testing of tablets.

  相似文献   
87.
Cp2Ti(dithiolene) and Cp2Ti(diselenolene) complexes containing the N-methyl-1,3-thiazoline-2-thione-4,5-dithiolate ligand (Me-thiazdt), the N-phenyl-1,3-thiazoline-2-thione-4,5-dithiolate ligand (Ph-thiazdt) and the N-methyl-1,3-thiazoline-2-thione-4,5-diselenolate ligand (Me-thiazds) have been synthesized. Three approaches have been developed in order to generate the dithiolene or the diselenolene ligands which were reacted with Cp2TiCl2 to form the corresponding heteroleptic complexes. Their X-ray crystal structures, UV-Vis absorption spectra as well as their redox properties, determined by cyclic voltammetry have been investigated and discussed. Variable-temperature 1H NMR experiments have been performed in order to determine the activation energies of the chelate ring inversion.  相似文献   
88.
This article presents a numerical approximation of the initial-boundary nonlinear coupled viscous Burgers’ equation based on spectral methods. A Jacobi-Gauss-Lobatto collocation (J-GL-C) scheme in combination with the implicit Runge-Kutta-Nyström (IRKN) scheme are employed to obtain highly accurate approximations to the mentioned problem. This J-GL-C method, based on Jacobi polynomials and Gauss-Lobatto quadrature integration, reduces solving the nonlinear coupled viscous Burgers’ equation to a system of nonlinear ordinary differential equation which is far easier to solve. The given examples show, by selecting relatively few J-GL-C points, the accuracy of the approximations and the utility of the approach over other analytical or numerical methods. The illustrative examples demonstrate the accuracy, efficiency, and versatility of the proposed algorithm.  相似文献   
89.
A highly sensitive, simple and rapid stability-indicating spectrofluorimetric method was developed for the determination of metolazone (MET) and xipamide (XPM) in their tablets. The proposed method is based on the measurement of the native fluorescence of MET in methanol at 437 nm after excitation at 238 nm and XPM in alkaline methanolic solution at 400 nm after excitation at 255 nm. The fluorescence–concentration plots were rectilinear over the range of 2.0– 20.0 ng/mL for MET and 0.2– 2.0 μg/mL for XPM, with lower detection limits (LOD) of 0.35 ng/mL and 0.02 μg/mL and a lower quantification limit (LOQ) of 1.05 ng/mL and 0.07 μg/mL for MET and XPM, respectively. The method was successfully applied to the analysis of MET and XPM in their commercial tablets and the results were in good agreement with those obtained using the official and comparison methods, respectively. Furthermore, content uniformity testing of the studied pharmaceutical tablets was also conducted. The application of the proposed method was extended to stability studies of MET and XPM after exposure to different forced degradation conditions, such as acidic, alkaline, oxidative and photolytic degradation conditions, according to ICH Guidelines. Moreover, the method was utilized to investigate the kinetics of the alkaline, acidic and photolytic degradation of MET. The apparent first-order rate constants and half-life times were calculated. Proposals for the degradation pathways for both MET and XPM were postulated.  相似文献   
90.
LiNi1/3Co1/3Mn1/3O2 (LNMCO) powders were formed by a two-step synthesis including preparation of an oxalate precursor by ??chimie douce?? followed by a solid-state reaction with lithium hydroxide. The product was characterized by TG-DTA, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), Raman spectroscopy, electron spin resonance (ESR), and SQUID magnetometry. XRD data revealed well-crystallized layered LNMCO with ??-NaFeO2-type structure (R-3?m space group). Morphology studied by SEM and TEM shows submicronic particles of 400?C800?nm with a tendency to agglomerate. The local structure investigated by vibrational spectroscopy (FTIR, Raman), ESR, and SQUID measurements confirms the well-crystallized lattice with a cation disorder of 2.6% Ni2+ ions in Li(3b) sites. Electrochemical tests were carried out in the potential range 2.5?C4.5?V vs. lithium metal on samples heated at 900?°C for 12?h. Initial discharge capacity is 154 mAh/g at C/5, while a capacity of 82 mAh/g is still delivered at 10 C by the two-step synthesized LiNi1/3Co1/3Mn1/3O2 as cathode material.  相似文献   
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