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We develop an anisotropic perfectly matched layer (PML) method for solving the time harmonic electromagnetic scattering problems in which the PML coordinate stretching is performed only in one direction outside a cuboid domain. The PML parameters such as the thickness of the layer and the absorbing medium property are determined through sharp a posteriori error estimates. Combined with the adaptive finite element method, the proposed adaptive anisotropic PML method provides a complete numerical strategy to solve the scattering problem in the framework of FEM which produces automatically a coarse mesh size away from the fixed domain and thus makes the total computational costs insensitive to the choice of the thickness of the PML layer. Numerical experiments are included to illustrate the competitive behavior of the proposed adaptive method. 相似文献
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Xiyue Xiong Zihui Yang Yongbin Huang Linbo Jiang Yingzhuang Chen Yao Shen Bo Chen 《Journal of separation science》2013,36(5):923-931
A novel construction strategy of monolithic capillary column for selectively enriching perfluorinated persistent organic pollutants was proposed. The organic–inorganic hybrid fluorous monolithic capillary column was synthesized by a “one‐pot” approach via the polycondensation of γ‐methacryloxypropyltrimethoxy‐silane, then in situ copolymerization of 1H,1H,7H‐dodecafluoroheptyl methacrylate and vinyl group on the precondensed siloxanes. The obtained monolithic columns were systematically characterized. The results demonstrated that the optimal column possessed good mechanical stability and high permeability. The adsorption capacities of the optimized monolithic column for perfluorooctanoic acid and perfluorooctane sulfonate were 0.257 and 0.513 μg/mg, respectively. Adsorption capacities of the monoliths were proved to increasing with increasing the amounts of fluorinated monomers in the fluorous monoliths. Sodium 1‐octanesulfonate, as a comparison compound, was hardly adsorbed on the fluorous monolith. In addition, the trace amounts of perfluorooctanoic acid and perfluorooctane sulfonate in water samples can be successfully concentrated about 160 times to their original concentrations by this monolithic column. These results demonstrated that the capacity and selectivity of the affinity fluorous column is high and can be applied to the selective enrichment for the perfluorinated persistent organic pollutants from environmental samples. 相似文献
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Linbo Zhang Tao Cui Hui Liu LSEC ICMSEC Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing China 《计算数学(英文版)》2009,(1):89-96
We present a program for computing symmetric quadrature rules on triangles and tetrahedra. A set of rules are obtained by using this program. Quadrature rules up to order 21 on triangles and up to order 14 on tetrahedra have been obtained which are useful for use in finite element computations. All rules presented here have positive weights with points lying within the integration domain. 相似文献
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Linbo Gu Yixi Cai Yunxi Shi Jing Wang Xiaoyu Pu Hui Xu Yingxin Cui 《Plasma Chemistry and Plasma Processing》2017,37(4):1193-1209
In order to investigate the effects of non-thermal plasma (NTP) on diesel particulate matter (PM), an engine test bench was built up. An engine exhaust particle sizer (EEPS) was introduced to analyze the emission concentration and size distribution of PM and a thermo-gravimetric analyzer was used to analyze the effects of NTP on the composition of the particulate matter in the exhaust gas. The results show that the size distribution interval of the particle mass concentration falls behind that of the quantity concentration under various loads. When the diesel engine operating speed is 2400 rpm and the load is 25%, after NTP, the proportions of the nucleation mode particles and the accumulative mode particles exhibit a small fluctuation while the proportion of ultrafine particles decreases by 10% due to their large quantity concentration. Under the dual effect of DPF and NTP, the particle quantity concentration decreases by 98%. In order to investigate the effect of NTP on the composition of the PM, a thermo-gravimetric analysis of the particles obtained before and after NTP was carried out. The results show that the proportion of volatile matter falls by 16.05% and solid carbon accounts for an increase of 7.29%. NTP has the ability to improve reduction activity of particles and make particles easier to be oxidized at a lower temperature. 相似文献
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GUAN Linbo 《力学与实践》1979,42(5):622
对地基土沉降计算的课程内容提出改革思路,从讨论土体固结度的角度展开,进而引出最终沉降量的计算,最终引出不同的试验方法和压缩性指标。新的教学思路将土力学固结沉降的基本理论与实践应用进行合理的区隔,既能保证基本理论的纯粹性、合理性,也不回避实践中土体复杂 性质对理论进一步发展和丰富所提出的挑战。 相似文献
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The compressible Navier-Stokes equations discretized with a fourth order accurate compact finite difference scheme with group velocity control are used to simulate the Richtmyer-Meshkov (R-M) instability problem produced by cylindrical shock-cylindrical material interface with shock Mach number Ms=1.2 and density ratio 1:20 (interior density/outer density). Effect of shock refraction, reflection, interaction of the reflected shock 相似文献
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We report a novel scheme to optimize the focusing condition for real-time, swept-source optical coherence microscopy. The axial and lateral behaviors of four-zone binary-phase spatial filters are presented numerically. A nearly constant axial intensity distribution along an extended depth of focus of 1.5 mm and a lateral resolution of 5 microm are experimentally verified. The A-line scan rate is up to 16 kHz, yielding a frame rate of 25 Hz and 640 lines per image. 相似文献
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A Two‐Coordinate Cobalt(II) Imido Complex with NHC Ligation: Synthesis,Structure, and Reactivity
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Jingzhen Du Linbo Wang Prof. Dr. Meihua Xie Prof. Dr. Liang Deng 《Angewandte Chemie (International ed. in English)》2015,54(43):12640-12644
The synthesis, structural characterization, and reactivity of the first two‐coordinate cobalt complex featuring a metal–element multiple bond [(IPr)Co(NDmp)] ( 4 ; IPr=1,3‐bis(2′,6′‐diisopropylphenyl)imidazole‐2‐ylidene; Dmp=2,6‐dimesitylphenyl) is reported. Complex 4 was prepared from the reaction of [(IPr)Co(η2‐vtms)2] (vtms=vinyltrimethylsilane) with DmpN3. An X‐ray diffraction study revealed its linear C? Co? N core and a short Co? N distance (1.691(6) Å). Spectroscopic characterization and calculation studies indicated the high‐spin nature of 4 and the multiple‐bond character of the Co? N bond. Complex 4 effected group‐transfer reactions to CO and ethylene to form isocyanide and imine, respectively. It also facilitated E? H (E=C, Si) σ‐bond activation of terminal alkyne and hydrosilanes to produce the corresponding cobalt(II) alkynyl and cobalt(II) hydride complexes as 1,2‐addition products. 相似文献
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应用Hamilton原理建立了双路传力的无轴承旋翼运动方程。采用均匀入流模型,基于直升机飞行平衡条件,建立了无轴承旋翼柔性梁载荷的计算模型,并通过算例验证了模型的精度。利用该模型,研究了全机重心位置、机身气动阻力以及平尾安装角对柔性梁载荷特性的影响,给出了各因素对柔性梁载荷的影响趋势,得出了降低柔性梁载荷的方法。数值结果表明:2cm左右重心位置的变化能够引起9%~11%的柔性梁载荷变化量,15%气动阻力的增加会导致约9%的柔性梁载荷的增大;2°平尾安装角的变化引起约10%柔性梁载荷的变化量,3°平尾安装角的变化引起约26%柔性梁载荷的变化。 相似文献