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971.
The application of Artificial Neural Networks (ANNs) for nonlinear multivariate calibration using simulated FTIR data was demonstrated in this paper. Neural networks consisting of three layers of nodes were trained by using the back-propagation learning rule. Since parameters affect the performance of the network greatly, simulated data were used to train the network in order to get a satisfactory combination of all parameters. The mixtures of four air toxic organic compounds whose FTIR spectra are overlapped were chosen to evaluate the calibration and prediction ability of the network. The relative standard error (RSD%), the percent standard error of prediction samples (%SEP) and the percent standard error of calibration samples (%SEC) are used for evaluating the ability of the neural network. 相似文献
972.
Dicyclohexyldithiophosphinic acid was synthesized by a three-step strategy through the Grignard reaction of PSCl3 with cyclo-C6H11MgBr and the P-P bond-cleavage reaction of the intermediate. The 1H NMR data of ammonium dicyclohexyldithiophosphinate 4 and dicyclohexyldithiophosphinic acid 5 were characterized by 1H-1H correlation spectra. 相似文献
973.
Yu Lin Song Chih Hsiao Cheng Luh-Maan Chang Chia-Fone Lee Yuan Fang Chou 《Applied Acoustics》2011,(12):949-952
Mono-disperse polycarbonate (PC) nanoparticles 20 nm in diameter was spray coated on silicon substrate using a novel high-frequency ultrasonic nozzle. Specifically, Bisphenol-A polycarbonate with a molecular weight (Mw) of approximately 6.4 × 104 g/mol was first dissolved in pyridine. The resulting solution was sprayed into surfactant-containing de-ionized (DI) water using a 300 kHz silicon-based multiple-Fourier horn nozzle (MFHN). As pyridine was extracted into the water, PC nanoparticles formed but remained dispersed. This suspension of PC nanoparticles was then sprayed onto a silicon substrate using a 500 kHz 3-Fourier horn nozzle. Scanning electron microscopy (SEM) of the dried substrate revealed that PC nanoparticles were spread uniformly with no aggregation. 相似文献
974.
In this note, by constructing suitable approximate solutions, we prove the existence of global weak solutions to the compressible Navier–Stokes equations with density-dependent viscosity coefficients in the whole space or exterior domain, when the initial data are spherically symmetric. In particular, we prove the existence of spherically symmetric solutions to the Saint-Venant model for shallow water in the whole space (or exterior domain). 相似文献
975.
Chunye Gong Jie Liu Lihua Chi Haowei Huang Jingyue Fang Zhenghu Gong 《Journal of computational physics》2011,230(15):6010-6022
Graphics Processing Unit (GPU), originally developed for real-time, high-definition 3D graphics in computer games, now provides great faculty in solving scientific applications. The basis of particle transport simulation is the time-dependent, multi-group, inhomogeneous Boltzmann transport equation. The numerical solution to the Boltzmann equation involves the discrete ordinates (Sn) method and the procedure of source iteration. In this paper, we present a GPU accelerated simulation of one energy group time-independent deterministic discrete ordinates particle transport in 3D Cartesian geometry (Sweep3D). The performance of the GPU simulations are reported with the simulations of vacuum boundary condition. The discussion of the relative advantages and disadvantages of the GPU implementation, the simulation on multi GPUs, the programming effort and code portability are also reported. The results show that the overall performance speedup of one NVIDIA Tesla M2050 GPU ranges from 2.56 compared with one Intel Xeon X5670 chip to 8.14 compared with one Intel Core Q6600 chip for no flux fixup. The simulation with flux fixup on one M2050 is 1.23 times faster than on one X5670. 相似文献
976.
Wen-Jun Liang Hong-Ping Fang Jian Li Feng Zheng Jing-Xin Li Yu-Quan Jin 《Journal of Electrostatics》2011,69(3):206-213
Destruction of hydrogen sulfide using dielectric barrier discharge plasma in a coaxial cylindrical reactor was carried out at atmospheric pressure and room temperature. Three types of DBD reactor were compared in terms of specific energy density (SED), equivalent capacitances of the gap (Cg) and the dielectric barrier (Cd), energy yield (EY), and H2S decomposition. In addition, byproducts during the decomposition of H2S and destruction mechanism were also investigated. SED for all the reactors depended almost linearly on the voltage. In general, Cg decreased with increasing voltage and with the existence of pellet material, while Cd displayed the opposite trend. The removal efficiency of H2S increased substantially with increasing AC frequency and applied voltage. Longer gas residence times also contributed to higher H2S removal efficiency. The choice of pellet material was an important factor influencing the H2S removal. The reactor filled with ceramic Raschig rings had the best H2S removal performance, with an EY of 7.30 g/kWh. The likely main products in the outlet effluent were H2O, SO2, and SO3. 相似文献
977.
Zhao Shiduo Li Qiming Li Fang Liang Zhihua 《Journal of Sol-Gel Science and Technology》2017,81(2):544-555
Journal of Sol-Gel Science and Technology - CuCo2O4 spinel nanoparticles were successfully preparedvia a sol–gel method, which were firstly employed in catalytic reduction of p-nitrophenol to... 相似文献
978.
Ying Tang Xiangjie Kong LiDe Fang Hongtao Wang 《Physica C: Superconductivity and its Applications》2011,471(23-24):1660-1663
Combined with the thermal analysis and phase identification, the influence of the B2O3 impurity in the original B powder on the phase formation of MgB2 during the sintering process was investigated. It is found that how the B2O3 impurity in the original B powder affects the sintering process of MgB2 depends on the reactivity of Mg particles in the original powder. If the Mg particles in the original powder are small and reactive enough, the B2O3 impurity could react with them before Mg melting during the sintering process and accelerate the solid–solid reaction between Mg and B. Otherwise, the B2O3 impurity could not react with Mg particles before Mg melting and depress the solid–solid reaction between Mg and B. 相似文献
979.
Qu Fengjin Ma Xiaoyan Hui Yuchen Chen Fang Gao Yan Chen Ying 《Journal of Solid State Electrochemistry》2017,21(6):1545-1557
Journal of Solid State Electrochemistry - As enzyme-immobilization and electron-transfer are the key factors for fabricating an enzymatic bioelectrode and its devices, we investigated a strategy to... 相似文献