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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 156-162页

作者： Qingdong CAI(State key Laboratory for Turbulence Research, Peking University, Beijing 100871, China) State key Laboratory for Turbulence Research Peking University Beijing 100871 China

A new technique in the formulation of numerical scheme for hyperbolicequation is developed. It is different from the classical FD and FE methods. We begin withthe algebraic equations with some undefined parameters, and get the difference equationthrough Taylor-series expansion. When the parameters in the partial difference equationare defined, the equation is what the scheme will simulate. The numerical example ofthe viscous Burgers equation shows the validity of the scheme. This method deals withthe numerical viscosity and dispersion exactly, giving a preliminary explanation to someproblems that the CFD face now.

关键词： modified equation Taylor expansion consistency truncation error

Expression of Recombinant Chinese Bovine Enterokinase Catalytic Subunit in P. pastoris and Its Purification and Characterization

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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 513-517页

作者： Lei FANG, Qi-Ming SUN, and Zi-Chun HUA*The State key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, China The State key Laboratory of Pharmaceutical Biotechnology Nanjing University Nanjing 210093 China

Enterokinase is a tool protease widely utilized in the cleavage of recombinant fusion proteins. cDNA encoding the catalytic subunit of Chinese bovine enterokinase (EKL) was amplified by PCR and then fused to the 3′ end of prepro secretion signal peptide gene of α-mating factor from Saccharomyces cerevisiae to get the α-MF signal-EKL-His6 encoding gene by PCR. Then the whole coding sequence was cloned into the integrative plasmid pAO815 under the control of a methanol-inducible promoter and transformed GS115 methylotrophic strain of Pichia pastoris. Secreted expression of recombinant EKL-His6 was attained by methanol induction and its molecular weight is 43 kD. Because of the existence of His6-tag, EKL-His6 was easily purified from P. pastoris fermentation supernatant by using Ni2+ affinity chromatography and the yield is 5.4 mg per liter of fermentation culture. This purified EKL-His6 demonstrates excellent cleavage activity towards fusion protein containing EK cleavage site.

关键词： recombinant enterokinase secreted expression Ni2+ affinity chromatography fusion protein cleavage

Mechanochemical decomposition of pentachlorophenol by ball milling

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Journal of Environmental Sciences 2009年第12期21卷 1761-1768页

作者： WEI Yinglei, YAN Jianhua, LU Shengyong, LI XiaodongState key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. State key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

The mechanochemical dechlorination of pentachlorophenol （PCP） was studied using CaO and SiO2 powder as additives. The effects of the milling time and additives on the dechlorination rate were investigated. The resulting product was characterized by X-ray diffraction （XRD）, Fourier transform infrared spectra （FT-IR）, thermogravimetric analysis （TG） and ion chromatography （IC）. It is found that grinding operation could dechlorinate PCP, with the formation of inorganic chloride and amorphous carbon. The addition of quartz to the grinding mixture facilitated dechlorination. On the basis of the experimental results, the decomposition mechanism was proposed. Decomposition predominantly proceeds through rupture of C-Cl bond in PCP molecule, followed by the formation of inorganic chlorides.

关键词： ball milling dechlorination mechanochemical pentachlorophenol

The endocrine regulation network of growth hormone synthesis and secretion in fish: Emphasis on the signal integration in somatotropes

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Science China(Life Sciences) 2010年第4期53卷 462-470页

作者： LI WenSheng & LIN HaoRan State key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Provincial key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China State key Laboratory of Biocontrol Institute of Aquatic Economic Animals and the Guangdong Provincial Key Laboratory for Aquatic Economic Animals School of Life Sciences Sun Yat-sen University Guangzhou China

In teleosts, growth hormone (GH) production is governed by multiple neuroendocrine factors from the hypothalamus and other regulators from the pituitary and peripheral organs. Exploring the principles followed by pituitary somatotropes when differentiating and integrating the signals from these regulators at the cellular and intracellular level is essential for understanding the endocrine regulation network of growth hormone synthesis and secretion in fish. This paper discusses recent advances in the action mechanisms of GH regulation factors, including the neuroendocrine regulators, pituitary level factors and peripheral factors, primarily involved in their receptor systems as well as in post-receptor signal transduction pathways.

关键词： fish growth hormone receptor signal transduction

DETERMINATION　OF　MECHANICAL　PROPERTIES　INMICROZONE　OF　METAL　MATRIX　COMPOSTITES　BY　ULTRAMICROHARDNESS

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中国有色金属学会会刊：英文版 1996年第4期6卷 122-126页

作者： Chen Yu Zhang Guoding(State key Lab of MMCs,Shanghai Jiao Tong University,Shanghai 200030) State key Lab. of MMCs Shanghai Jiao Tong University Shanghai 200030 China

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ＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＩＮＭＩＣＲＯＺＯＮＥＯＦＭＥＴＡＬＭＡＴＲＩＸＣＯＭＰＯＳＴＩＴＥＳＢＹＵＬＴＲＡＭＩＣＲＯＨＡＲＤＮＥＳＳ￥ＣｈｅｎＹｕ；ＺｈａｎｇＧｕｏｄｉｎｇ（ＳｔａｔｅＫｅｙＬａｂｏｆＭ...

关键词： ultramicrohardness interface metal matrix composites residual stress

Effects of chlorothalonil and carbendazim on nitrification and denitrification in soils

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Journal of Environmental Sciences 2009年第4期21卷 458-467页

作者： LANG Man, CAI Zucong State key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences,Nanjing 210008, China State key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

The effects of chlorothalonil and carbendazim on nitrification and denitrification in six soils in upland and rice paddy environments were investigated. Laboratory aerobic （60% water holding capacity） and anaerobic （flooded） conditions were studied at 25℃ and fungicide addition rates of 5.5 mg/kg A. I. （field rate, FR）, 20 times （20FR） and 40 times （40FR） field rate, respectively. The results indicated that chlorothalonil at the field rate had a slight inhibitory effect on one soil only, and that soil did not nitrify much in the first place. But chlorothalonil at higher rates inhibited nitrification significantly in all soils. For soils JXP and JXU with a pH of less than 5.0, chlorothalonil almost completely stopped their nitrification at 20FR and 40FR during the whole 14 d incubation period. For soils HNP and HNU with a pH of greater than 8.0, chlorothalonil also significantly inhibit nitrification at 20FR and 40FR （p 〈 0.05）. However, NH4＋ that was added to the soil was also almost completely nitrified by the end of the incubation period in these two soils. The effects of chlorothalonil at 20FR and 40FR on the nitrification of JSP and JSU soils, with a pH of 5.4 and 7.2, respectively, were intermediate between the other soil types. Chlorothalonil had no effect on denitrification at the field rate and had little effect at the higher rates of application in some soils. Carbendazim had essentially no effect on nitrification and denitrification in soils assessed.

关键词： fungicide nitrification denitrification chlorothalonil carbendazim

SIMULATION OF FLUID FLOW IN CHANNEL OF A NOVEL HYDRAULIC SHOCK GENERATOR

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Chinese Journal of Mechanical Engineering 2000年第4期13卷 258-262页

作者： Fu XinYang Huayong (State key Laboratory of Fluid Power Transmission and Control, Zhejiang University) 浙江大学流体传动及控制国家重点实验室浙江杭州

In order to improve the engineering performance of a novel hydraulic shock generator, the fluid flow inside its complex passages is numerically investigated. The effects of the inlet flow velocity upon the turbulence intensity of the jet flow are analyzed. The calculated pressure loss is experimentally verified with the consideration of temperature determined viscosity shifting. The results are used as the reference in the further development of the hydraulic shock generator

关键词： Shock generator Numerical simulation Jet flow Turbulence

CORRECTION METHODS FOR STEADY INCOMPRESSIBLE FLOWS

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Journal of Computational Mathematics 1999年第4期17卷 419-424页

作者： Jian Li(State key Laboratory of Scientific and Engineering Computing, ICMSEC, Chinese Academy of Sciences, Beijing 100080, China) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

Correction methods for the steady semi-periodic motion of incompressible fluid are investigated. The idea is similar to the influence matrix to solve the lack of vorticity boundary conditions. For any given boundary condition of the vorticity, the coupled vorticity-stream function formulation is solved. Then solve the governing equations with the correction boundary conditions to improve the solution. These equations are numerically solved by Fourier series truncation and finite difference method. The two numerical techniques are employed to treat the non-linear terms. The first method for small Reynolds number R equals 0-50 has the same results as that in M. Anwar and S.C.R. Dennis' report. The second one for R greater than 50 obtains the reliable results. (Author abstract) 4 Refs.

关键词： incompressible flow vorticity stream function numerical solution

Optimization of gasoline hydrocarbon compositions for reducing exhaust emissions

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Journal of Environmental Sciences 2009年第9期21卷 1208-1213页

作者： SHEN Yitao,SHUAI Shijin,WANG Jianxin,XIAO Jianhua State key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China State key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China

Effects of hydrocarbon compositions on raw exhaust emissions and combustion processes were studied on an engine test bench. The optimization of gasoline hydrocarbon composition was discussed. As olefins content increased from 10.0% to 25.0% in volume, the combustion duration was shortened by about 2 degree crank angle （°CA）, and the engine-out THC emission was reduced by about 15%. On the other hand, as aromatics content changed from 35.0% to 45.0%, the engine-out NOx emissions increased by 4%. An increment in olefins content resulted in a slight increase in engine-out CO emission, while the aromatics content had little effect on engine-out total hydrocarbon （THC） and CO emissions. Over the new European driving cycle （NEDC）, the THC, NOx and CO emissions of fuel with 25.0% olefins and 35.0% aromatics were about 45%, 21% and 19% lower than those of fuel with 10.0% olefins and 40.0% aromatics, respectively. The optimized gasoline compositions for new engines and new vehicles have low aromatics and high olefins contents.

关键词： optimization hydrocarbon composition exhaust emissions olefins aromatics

MODELING AND INTEGRATED CONTROL FOR A METAL PUSHING BELT CONTINUOUSLY VARIABLE TRANSMISSION SYSTEM

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Chinese Journal of Mechanical Engineering 2001年第4期14卷 336-341页

作者： Hu Jianjun, Qin Datong, Sun Dongye (State key Laboratory of Mechanical Transmission,Chongqing University) 重庆大学机械传动国家重点实验室重庆

By the bond graph theory,a bond graph analysis model of continuously variable transmission is established On the basis of improving the ratio change response and reducing the engine torque response lag in normal control,a new synthetic control algorithm is developed By analyzing the engine driving torque characteristics and the transmission inertia torque while ratio is changed under transient condition,the compensation value for engine driving torque is presented The simulation result shows that by this compensation control algorithm the engine torque response lag can be reduced and the driving torque response can be improved effectively.

关键词： Continuously variable transmission Modeling Control