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Existing home devices in home network provides only independent services limited on a homogeneous protocol and/or do not fully support an intelligent service provided by cooperating among heterogeneous protocol devices. This paper proposes an intelligent and integrated service binding architecture which allow the users to figure out the status of devices and to cooperate among home network devices regardless of supported protocols or operational characteristics.  相似文献   
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A novel epoxy system was developed through the in situ curing of bisphenol A type epoxy and 4,4′‐diaminodiphenylmethane with the sol–gel reaction of a phosphorus‐containing trimethoxysilane (DOPO–GPTMS), which was prepared from the reaction of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) with 3‐glycidoxypropyltrimethoxysilane (GPTMS). The preparation of DOPO–GPTMS was confirmed with Fourier transform infrared, 1H and 31P NMR, and elemental analysis. The resulting organic–inorganic hybrid epoxy resins exhibited a high glass‐transition temperature (167 °C), good thermal stability over 320 °C, and a high limited oxygen index of 28.5. The synergism of phosphorus and silicon on flame retardance was observed. Moreover, the kinetics of the thermal oxidative degradation of the hybrid epoxy resins were studied. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2354–2367, 2003  相似文献   
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It is shown that in the case of shapeinvariance, with the use of the mixing functionformalism, exact solvability of the Schrodinger equationcan be obtained without recourse to the technique ofsupersymmetrization. Some consequences of the method are outlinedand illustrated by specific examples.  相似文献   
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The possibility of Pt–Cr surface alloys formation on Pt(0 0 1) was investigated and their magnetism was calculated by the full-potential linearized augmented plane wave (FLAPW) method with eight different atomic configurations. The most stable structure was calculated to be the Pt-segregated L12 ferromagnetic surface alloy. A3B types (L12 or D022) were more stable compared to AB types (L10). It implies that the A3B type surface alloys may be formed when depositing a monolayer of Cr on Pt(0 0 1). It was found from the total energy calculations that there exists a strong tendency of the Pt segregation. The segregation further stabilizes the surface alloy significantly. The work function of the most stable surface alloy was calculated to be 6.02 eV and the magnetic moment of the surface Cr was much enhanced to 3.3 μB. It is a quite interesting finding that the coupling between Cr and Pt atoms on the surface plane is ferromagnetic in the Pt-segregated L12 ferromagnetic surface alloy, while the coupling is antiferromagnetic in the bulk.  相似文献   
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A new porphyrin, peroxyacetic acid uroporphyrin I, has been isolated from the urine of patients with congenital erythropoietic porphyria by reversed phase high performance liquid chromatography. The porphyrin was characterized by high resolution mass spectrometry and by typical chemical reactions of a peroxyacid.  相似文献   
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推行财政国库管理制度改革是目前我国公共财政支出改革的重要环节。本文以攀枝花市为例对财政国库集中支付改革中存在的问题作了比较深入的分析,在此基础上提出了解决问题的几点对策。  相似文献   
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We describe the inclusion of nonequilibrium gain into a self-consistent 2.5D CW spectral laser diode model and report on the use of this model to investigate the origin of gain compression in a 975 nm high-brightness tapered QW laser diode. Nonequilibrium gain is calculated using a dynamic gain model, which simulates the dynamic relaxation of the quantum well carrier energy distributions under the influence of steady-state electrical and optical excitation. Calculated gain and spontaneous emission spectra are included in the laser model via parameterised look up tables. Both simulated and experimentally measured intracavity spontaneous emission spectra show an increased carrier density and a blue-shift of the gain maximum with increasing bias caused by carrier heating and spectral hole burning. The accurate incorporation of nonequilibrium gain compression is therefore vital for the accurate prediction of the operating characteristics of these devices and for the experimental determination of the active region temperature.  相似文献   
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