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AN UNSPLIT LAGRANGIAN ADVECTION SCHEME FOR VOLUME OF FLUID METHOD

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Journal of Hydrodynamics 2010年第1期22卷 73-80页

作者： yang wei LIU Shu-hong WU Yu-lin Laboratory of Hydraulic Science and Engineering Tsinghua University Beijing 100084 China

An Unsplit Lagrangian Advection （ULA） scheme for Volume Of Fluid （VOF） method is presented in this article. The ULA scheme is developed based on an algorithm of Piecewise Linear Interface Construction （PLIC）. The volume fluxes between cells are calculated through solving the new equation of the linear interfaces in cells in the ULA scheme. The fluxes flowing out from one cell is the inflow fluxes for another cell. In this way the whole fluid volume is conserved strictly without using any redistribution algorithms. The ULA scheme is based on two-dimensional structured rectangular mesh and may be extended to three-dimensional structured mesh with more geometrical efforts. The results from three widely-used benchmark tests show that the ULA scheme can achieve the accuracy higher than Split Lagaragian Advection （SLA） scheme and the Flux-Corrected Transport （FCT） algorithm.

关键词： advection schemes free surfaces fluid interfaces Volume Of Fluid (VOF) method

Numerical Simulation of High Temperature Air Combustion Flames Properties

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Journal of Central South University 2000年第3期12卷 156-158页

作者： yang wei-hong JIANG Shao-jiang HSIAO Tse-chiang yang Li-xing Department of Applied Physics and Heating Engineering Central South UniversityChangsha 410083China Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

High temperature air combustion (HTAC) is an attractive technology of saving energy and controlling environment. The mathematical models of turbulent jet flame under the highly preheated air combustion condition are conducted in the paper. The mixture fraction/probability density function model is employed. The results show that the maximum flame temperature is decreased, the temperature in the HTAC furnace is more uniform than that in the conventional furnace, and the NO x emission is low. The numerical results are partially validated by some experimental measurements.

关键词： high temperature air combustion numerical simulation flame low oxgen

Transfer and transport of aluminum in filtration unit

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Journal of Environmental Sciences 2007年第8期19卷 897-901页

作者： WANG Wen-dong yang hong-wei ZHAO Hua-zhang JIANG Zhan-peng Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China. Department of Environmental Science and Engineering Peking University Beijing 100871 China

Aluminum salt coagulants were used prevalently in various water works. In this article, the effects of filtration on residual aluminum concentration and species distribution were researched by determining the concentration of different aluminum species before and after single layer filter, double layer filter, and membrane filtration units. In the research, size exclusion chromatography （SEC） was used to separate colloidal and soluble aluminum, ion exchange chromatography （IEC） was used to separate organic and inorganic aluminum, and inductivity coupled plasma-atomic emission spectrometry （ICP-AES） was used to determine the aluminum concentration. The results showed that the rapid filtration process had the ability of removing residual aluminum from coagulant effluent water, and that double layer filtration was more effective in residual aluminum removal than single layer filtration, while nano filtration was more effective than micro filtration. It was found that when the residual aluminum concentration was below lmg/L in sediment effluent, the residual aluminum concentration in treated water was above 0.2 mg/L. The direct rapid filtration process mainly removed the suspended aluminum. The removal of soluble and colloidal aluminum was always less than 10% and the natural small particles that adsorbed the amount of soluble or small particles aluminum on their surface were difficult to be removed in this process. Micro filtration and nano filtration were good technologies for removing aluminum; the residual aluminum concentration in the effluent was less than 0.05 mg/L.

关键词： aluminum species membrane filtration rapid filtration

Non-fragile H∞ Filtering for Discrete-time Systems with Finite Word Length Consideration

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自动化学报 2008年第8期34卷 886-892页

作者： CHE wei-wei yang Guang-hong Key Laboratory of Integrated Automation for the Process Industry Ministry of Education College of Information Science and Engineering Northeastern University Shenyang 110004 P.R. China

过滤有限的词长度(FWL ) 为线性分离时间的系统影响的问题的 nonfragile H 在这份报纸被调查。要设计的过滤器被假定与添加剂获得变化，它在过滤器实现上反映 FWL 效果。结构化的顶点隔板的一个观点被建议处理这个问题并且利用了以一套... 详细信息

过滤有限的词长度(FWL ) 为线性分离时间的系统影响的问题的 nonfragile H 在这份报纸被调查。要设计的过滤器被假定与添加剂获得变化，它在过滤器实现上反映 FWL 效果。结构化的顶点隔板的一个观点被建议处理这个问题并且利用了以一套线性矩阵不平等(LMI ) 为 nonfragile H 过滤器设计开发足够的条件。设计使扩充系统变为 asymptotically 稳定并且保证 H 变细水平不到规定水平。一个数字例子被给说明建议方法的效果。

关键词：滤波离散时间系统线性离散分析方法

Optical Absorption in SiGe/Si Quantum Well Structures Created by Subband Transitions

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Chinese Physics Letters 2001年第12期18卷 1655-1657页

作者： yang Yu MAO Xu yang hong-wei ZHOU wei ZHOU Zhen-Lai LIU Huan-Lin WANG Xun Department of Materials Science and Engineering Yunnan UniversityKunming 650091 Surface Physics Laboratory Fudan UniversityShanghai 200433

The absorption in Si_(1-x)Ge_(x)/Si multiple quantum-well structures is measured. Several separated well absorption peaks corresponding to both intersubband and intervalence band transitions in the samples are observed. In the normal incidence, two broadband peaks are attributed to intervalence band transitions HH0-SO0(2.5μm),HH_(0)-LH_(0)(~ 3μm), respectively. Using 45° incidence of unpolarized light, both the intervalence band and intersubband transitions are observed. The intervalence band transitions (HH_(0)-LH_(0) ) are Ge composition dependent, but the intersubband transitions, HH_(0)-HH_(1) (5.9μm) and HH_(0)-HH_(2)( 4.3 μm), are not sensitive to the Ge composition.

关键词： transitions valence absorption

The Features of Microcontroller EM78P447 and Technique of Port Connection with I^2C Series Bus

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Wuhan University Journal of Natural Sciences 2000年第4期5卷 461-463页

作者： Huang Ji-wu yang hong-wei Li yang Shen Rui-hua You Zhi Wuhan University College of Electronic Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) Wuhan Zhongyou Technology Commerce & Ind Ltd Wuhan China (GRID:grid.49470.3e) Hubei University College of Physics and Electronic Technology Wuhan China (GRID:grid.34418.3a) (ISNI:***)

By describing the technique of port connection and flow chart ofR/W operation between 24LC01, serial E2PROM, and EM78P447A, features of EM78P447 and its connection with I2C serial bus are introduced. In the end, the p... 详细信息

关键词： EM78P447A microcontroller I2C series bus 24LC01 technique of port connection

Synthesis and nonlinear optical properties of copolymers of fluoro-containing bisphenol A and chromophores

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Chinese Chemical Letters 2011年第11期22卷 1367-1370页

作者： Jie Ping Shi Hui yang Li wei hong Wen Hu Guo Yuan Lu Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

A series of new fluoro-containing copolymers have been synthesized by a Mitsunobu reaction with 4,4＇-（hexafluoroisopropylidene） bisphenol A（6FBPA） and the corresponding N,N-dihydroxyethylaminoaryl azo or ring-locked triene compounds, which have high thermal stability and good solubility in organic *** nonlinear optical（NLO） measurements made by Marker fringe method at 1064 nm indicate that the copolymers embedded with the ring-locked triene and azo chromophores exhibit higher macroscopic nonlinear optical coefficient（70.2 pm/V and 26.5-34.6 pm/V,respectively）.Thermal analysis and UV-visible absorption spectra show that the copolymers have good thermal stability（T_d= 264-319℃） and optical transparency （λ_（max）500 nm）.

关键词： NLO materials NLO chromophores Ring-locked triene Mitsunobu reaction

A Comparison Study on Corrosion Resistance of 430 Stainless Steel Surfaces Modified by Alkylsilane and Fluoroalkylsilane SAMs

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Journal of Iron and Steel Research International 2013年第12期20卷 75-81页

作者： WANG Hai-ren XIAO Zhen QU Jun-e yang hong-wei CAO Zhi-yong GUO Xing-peng School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Faculty of Materials Science and Engineering Hubei University Wuhan Branch Company SINOPEC

The self-assembly monolayers （SAMs） of n-dodecyltriethoxysilane （DTES） and 1 H, 1 H, 2H, 2H-perflu- orodecyltriethoxysilane （PFDS） on the surface of the 430 stainless steel （430SS） were prepared and their corrosion protection performance was investigated by potentiodynamic polarization, Fourier transform infrared spectroscopy （FTIR） -attenuated total reflection （ATR）, static contact angle and atomic force microscopy （AFM）. The results showed that the alkali pretreatment and the water added into the self-assembly solution could generate more hydrox- yls on the 430SS surface, and then enhanced the adsorption of the SAMs. A suitable temperature of the self-assem- bly solution is important for the formation of the SAMs. The silane SAMs were chemically adsorbed on the 430SS substrates by Fe-O-Si bonds. In all cases tested, PFDS has a better inhibition effect compared with DTES, and the difference in inhibition effect is most marked at the lowest concentration of 1 mmol/L.

关键词： 430 stainless steel (430SS) self-assembly monolayer (SAM) silane corrosion protection

Experimental study on fracture and gushing mechanism of surrounding rock of fault caused by tunnel excavation disturbance

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Yantu Lixue/Rock and Soil Mechanics 2020年 41卷 405-413页

作者： Li, yang-yang yang, wei-hong Zhang, Shi-Chuang Xu, Ya-Dong Guan, Yu-Qi Sun, Jian State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology Qingdao 266590 China Linyi Shandong Energy Mining Group Co. Ltd Linyi 276017 China

Tunnel water inrush has the characteristics of strong suddenness and great disaster, the crack propagation and coalescence, and gushing formation mechanism of surrounding rocks are relatively complicated. In order to study the fracture and gushing mechanism of surrounding rock under the disturbance of tunnel excavation, a subway station was taken as the engineering background a non-hydrophilic fluid-solid coupling similar material was developed to meet similar conditions, simulation test of fracture and gushing of surrounding rock of fault caused by tunnel excavation disturbance was conducted. The research results show that the main influence range of tunnel excavation on the surrounding rock of the side wall is within 1 times the diameter, and the rock within the disturbance range will experience loosening and squeezing movement. Excavation disturbance could affect the internal rock up to twice the diameter, while the main affected area is within the range of 1 times 1 times the diameter. When the tunnel face is far away from the fault, the change in fault water pressure is mainly concentrated in the excavation gap. The fractures in the surrounding rock of the fault will expand in stages due to the influence of the fault hydraulic pressure. When the tunnel faces is near the fault, the excavation disturbance has greater influence on the surrounding rock of the fault, the frequency of phased expansion of surrounding rock fissures increases, and the single amplitude decreases, while the total change increase by 1/3. According to the comprehensive analysis of test data, the surrounding rock of the tunnel has produced a connecting fissure connected to the fault surrounding rock at twice the diameter of the tunnel after the completion of the first stage of the tunnel excavation. With the advancement of tunnel excavation, connected fissures were successively generated at the arch waist and shoulder of the tunnel. Under the influence of the fault hydraulic pressure and exc

关键词： Fracture