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Analytic Solution for Magnetohydrodynamic Stagnation Point Flow towards a Stretching Sheet 下载免费PDF全文
A steady two-dimensional magnetohydrodynamic stagnation point flow towards a stretching sheet with variable surface temperature is investigated. The analytic solution is obtained by homotopy analysis method. The convergence region is computed and the feature of the solution is discussed. 相似文献
995.
996.
A series of novel monooxazoline-Schiff base ligands 1 has been successfully synthesized. The Cu(I)–1a complex showed excellent catalytic activities with up to 83% ee for the asymmetric α-chlorination of β-keto esters. 相似文献
997.
Broadband Convergence of 40 GHz-ROF and 10-Gb/s WDM-PON Systems in the Duplex Access Network 下载免费PDF全文
A broadly converged 40G-ROF and 10-Gb/s WDM-PON multi-service access system is proposed and exper- imentally demonstrated. This scheme consists of an integrated system of 40G-ROF and 10-Gb/s WDM-PON simultaneously transmitting independent 2.5-Gb/s wireless and 10-Gb/s wire signal. At the base station, it employs a remodulation scheme, which is achieved by remodulating the upstream OOK signal on the DPSK downstream signal, to reduce the cost of the base station. The transmission experiment is carried out over a 25-km-long single mode fiber (SMF-28). The results show that the sensitivities of downstream PON and ROF signal are -14.5 dBm and -21.5 dBm, respectively, and the sensitivity of upstream signal is -25.3 dBm. 相似文献
998.
Meijuan Yu Shulei Tian Wangsheng Chu Dongliang Chen Qi Wang Ziyu Wu 《Journal of synchrotron radiation》2009,16(4):528-532
The evaporation aerosols produced during the vitrification process of municipal solid waste incinerators (MSWI) fly ash represent a potential environmental risk owing to their high content of heavy metals. In this research, high‐temperature heating processes were carried out on fly ashes collected from bag houses in a Chinese MSWI plant and the secondary fly ashes (SFA) were separately collected at three high temperatures (1273 K, 1423 K and 1523 K) below the melting range. Elemental analysis showed that high contents of both zinc and chlorine were present in these SFA samples and, according to the standard of the heavy metals industrial grade of ore, SFAs can be re‐used as metallurgical raw materials or rich ore. Moreover, as shown by XAS analysis and for different high temperatures, zinc environments in the three SFA samples were characterized by the same local structure of the zinc chloride. As a consequence, a zinc recycling procedure can be easily designed based on the configuration information. 相似文献
999.
Ag3PW12O40 and Ag4SiW12O40 showed high activity and stability in the synthesis of diethylene glycol ethyl ether with diethylene glycol and ethanol, on which the conversion is 80.2% and 78.4%, respectively, and the selectivity of diethylene glycol ether is 75.4% and 80.6%, respectively. After the third reaction cycle, Ag3PW12O40 and Ag4SiW12O40) still showed higher activity and selectivity, on which the conversion is 72. 6% and 77.5% respectively. But the activity of Ag3PMo12O40 is lower, the conversion is only 21.0%. IR, XRD, TG and n‐butylamine titrimetry showed that the catalysis may be connected with two kinds of acidic centers owned by heteropoly acidic salt. 相似文献
1000.
In the fifties, Calderón established a formal relation between symbol and kernel distribution, but it is difficult to establish an intrinsic relation. The Calderón-Zygmund (C-Z) school studied the C-Z operators, and Hörmander, Kohn and Nirenberg, et al. studied the symbolic operators. Here we apply a refinement of the Littlewood-Paley (L-P) decomposition, analyse under new wavelet bases, to characterize both symbolic operators spaces \({\text{OP}}S^{m}_{{1,\delta }} \) and kernel distributions spaces with other spaces composed of some almost diagonal matrices, then get an isometric between \({\text{OP}}S^{m}_{{1,\delta }} \) and kernel distribution spaces 相似文献