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This study focuses on exact solutions of nonlinear Schrödinger equation in a power law media with fourth order dispersion. Jacobi elliptic functions will be used to carry out the integration of this equation. Bright, dark and singular optical soliton solutions are obtained as well as Jacobi elliptic function solutions.  相似文献   
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We are now preparing for the third generation (e,e′K~+) A hypernuclear spectroscopic experiment at Hall C,Jefferson Lab (USA).The goal of the experiment is the precise spectroscopy of hypernuclei in wide mass region.We have constructed a new high resolution electron spectrometer "HES" dedicated to (e,e′K~+) hypernuclear study in Japan and it was shipped to JLab in February,2008.We will discuss about the physics of the (e,e′K~+) hypernuclear study at JLab and report the current preparation status of the third generatrion experiment.  相似文献   
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Journal of Thermal Analysis and Calorimetry - Solid oxide fuel cell (SOFC) is a very efficient and clean source of energy. The glass and glass-ceramics are the most suitable and compatible sealing...  相似文献   
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A glass with the composition of the SiO2–Na2O–CaO–P2O5 was synthesized by sol–gel method at temperature of 900 °C, and then yttrium-, silver- and cerium-containing glasses were prepared at the same conditions using this base system. The structural and thermal properties of the glass samples were investigated by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, energy-dispersive X-ray (EDX) spectroscopy and differential thermal analysis techniques. The Ca5(PO4)2(SiO4)6 phase having the orthorhombic crystal system is detected for each sample without any secondary phase, and this phase is confirmed by the FTIR spectra. With the addition of Y, Ag and Ce to the SiO2–Na2O–CaO–P2O5 system, the variations in the average crystallite size, crystallinity percent, lattice parameters and unit cell volume are observed. A decrease in the crystallization peak temperature and the changes in the glass transition temperature are seen with the addition of Y, Ag and Ce to the base system. The addition of Y, Ag and Ce to the base glass increases significantly its density. The EDX spectra of the as-prepared samples verify the introduction of the as-mentioned elements.  相似文献   
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Polysulfone/poly(ethylene glycol) amphiphilic networks were prepared via in situ photo-induced free radical crosslinking polymerization. First, the hydrophobic polysulfone diacrylate (PSU-DA) oligomer was synthesized by condensation polymerization and subsequent esterification processes. Then, the obtained oligomer was co-crosslinked with the hydrophilic poly(ethylene glycol) diacrylate (PEG-DA) or poly(ethylene glycol) methyl ether acrylate (PEG-MA) at different feed ratios. In the case of PEG-MA, the resulting network possessed dangling pendant hydrophilic chains on the crosslinked surface. The structure and the morphology of the membranes were characterized by attenuated total reflection infrared spectroscopy (ATR-IR) and scanning electron microscopy (SEM). The enhancement of surface hydrophilicity was investigated by water contact angle measurements. The biomolecule adsorption properties of these networks were also studied. The biomolecules easily adsorbed on the surface of the hydrophobic polysulfone networks whereas dangling hydrophilic chains on the surface prevented the adsorption of the biomolecules.  相似文献   
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Timed communicating sequential processes (TCSP) language is used to specify fine-grain and coarse-grain multimedia synchronization. A lip synchronization system is an example of fine-grain synchronization. Several groupware scenarios are examples of coarse-grain synchronization. The formal specifications are used as the basis of verification and simulation. Safety and liveness timing requirements of the synchronization system are stated in terms of temporal logic formulas. Correctness analysis of the specification is shown using the temporal formulas and TCSP proof theory. It is shown that TCSP is powerful enough to be used in multimedia system design and verification. Next, simulation of multimedia synchronization is discussed. Various simulation models are developed for fine- and coarse-grain synchronization systems. It is shown that simulation modeling can lead to early detection of possible synchronization violations. The buffering requirements of a given synchronization mechanism can be effectively studied using simulation  相似文献   
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