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Journal of Environmental sciences 2001年第3期13卷 337-341页

作者： HUANG yi, TAO Shu(department of Urban and Environmental {2., Peking {2., Beijing 100871, china. department of Urban and Environmental sciences Peking University Beijing 100871 China. yhuang@***

Concentration of copper and zinc in isolated Suillus bovinus mycelia, used nutrient solution and 0.5 mol/L EDTA mycelia washing solution were measured to investigate the distribution of heavy metals in mycelia growth in excess copper or zinc nutrient solution. Treated with zinc, most of added zinc maintained in used solution, and 9.8%/14.6% was in/on mycelia in treatment, and in treatment 2.was 3.9%/8.0% in/on mycelia. In the copper applications, copper stimulated in more than on mycelia, i.e., 2..9%/4.5% in/on mycelia in treatment, and 7%/18.8% in/on mycelia while most of copper retained in used nutrient solution. Certain amount of copper or zinc uptake by mycelia led to pronounced influence on glycolysis and nitrogen incorporating process of Suillus bovinus, while the tested enzymes kept constant in treatment. In crude extracts of copper treatment 2.mycelia, activities of HK, PFK and GS were inhibited and decrease to 63%, 48% and 38% and GIDH increased by 68% of the control, respectively. The behaviors of these tested enzymes toward zinc corresponded in general with that towards copper. The potential protection of Suillus bovinus for its host plant under excess copper or zinc threaten was discussed.

关键词： Suillus bovinus ectomycorrhizal fungous copper zinc glycolysis nitrogen incorporate enzymes

To enhance the reproduction of Phanerochaete chrysosporium by adding natural lixiviums in liquid medium

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Journal of Environmental sciences 2003年第6期15卷 808-814页

作者： LIN Gang, WEN Xiang-hua, QIAN yi (department of Environmental Science and Engineering,{2., Beijing 100084,{2.. department of Environmental Science and Engineering Tsinghua University Beijing 100084 Chin

Great promotion to the reproduction of white rot fungus Phanerochaete chrysosporium by adding natural lixiviums such as from wood, maize core and potato in liquid medium was found in this research. Incubated in the liquid medium contained 10 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet reaches more than 80 g/L, which is 5 times more than that of without natural lixiviums. Incubated in the liquid medium contained 5 mg/L glucose as carbon source with natural lixiviums for three days, the production of mycelium pellet can reach 69.5 g/L, while the production in the medium without natural lixiviums is very low. When the liquid medium contained 1—2. g/L glucose as carbon source, the production of mycelium pellet in 3 d can only reach 12.5 g/L to 14.5 g/L. The fungus in the medium with potato lixiviums are easily contaminated by other microorganisms and in the medium with maize core lixiviums are easily bulking, while in the medium with wood lixiviums are neither easily contaminated nor bulking. Medium with wood lixiviums can produce more pellet than other medium, endure contamination and keep better sedimentation capacity. So that, wood lixivium is better additive to the culture of white rot fungi in liquid medium. Addition of the mixture of wood, maize core and potato lixiviums is of advantage to the production of mycelium pellet. The difference of the production in the medium with different amount of wood lixiviums showed little in the first 3 d, while it expanded after 3 d. Wood lixiviums stimulate the growth of P. chrysosporium instead of supply organics which fungi need.

关键词： white rot fungi medium additive

FL-FN-MOGA Based Traffic Signal Control

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Journal of Systems Engineering and Electronics 2003年第3期14卷 14-23页

作者： Wei Wu & Zhang yi department of Automation,{2., Beijing 100084, P. R.{2. department of Automation Tsinghua University Beijing 100084 P. R. China

In this paper, a traffic signal control method based on fuzzy logic (FL), fuzzy-neuro (FN) and multi-objective genetic algorithms (MOGA) for an isolated four-approach intersection with through and left-turning movements is presented. This method has an adaptive signal timing ability, and can make adjustments to signal timing in response to observed *** 'urgency degree' term, which can describe the different user's demand for green time is used in decision-making by which strategy of signal timing can be determined. Using a fuzzy logic controller, we can determine whether to extend or terminate the current signal phase and select the sequences of phases. In this paper, a method based on fuzzy-neuro can be used to predict traffic parameters used in fuzzy logic controller. The feasibility of using a multi-objective genetic algorithm ( MOGA) to find a group of optimizing sets of parameters for fuzzy logic controller depending on different objects is also demonstrated. Simulation results show that the proposed methed is effecfive to adjust the signal timing in response to changing traffic conditions on a real-time basis, and the controller can produce lower vehicle delays and percentage of stopped vehicles than a traffic-actuated controller.

关键词： Traffic signal control Fuzzy logic Fuzzy-neuro Multi-objective genetic algorithms.

SIMULATION OF FLUID-SOLID INTERACTION ON WATER DITCHING OF AN AIRPLANE BY ALE METHOD

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Journal of Hydrodynamics 2011年第5期23卷 637-642页

作者： HUA Cheng fang Chao CHENG Jin department of Mechanics and Engineering Science Fudan University Shanghai 200433 China School of mathematical sciences Fudan University Shanghai 200433 China

Ditching is considered as one of the important aspects of safety performances of airplanes. It is related primarily with the fluid-solid interaction, whose studies mainly depend on experiments at the present time. Numerical and analytical methods for fluid-solid interaction by using 3-D full scale airplane＇s model will reduce the dependence on the expensive model tests. Numerical studies can be used to estimate the safety of ditching and provide a reference for the crashworthiness design. This article proposes a 3-D dynamical structural model after the real shape of an airplane and an Arbitrary Lagrange-Euler （ALE） fluid-field model, to simulate the fluid-solid interactions caused by low speed ditching. The simulation is based on interaction computational methods, within LS-DYNA nonlinear finite-element code. The results of pressure distributions and accelerating time histories of the airplane＇s subfloor are discussed in the context of the safety of ditching, and the simulation results and the analytical methods are verified.

关键词： ditching fluid structure interaction Arbitrary Lagrange-Euler (ALE) finite element method

Oroclinal bending and block rotations in South china since the Mesozoic——Geological and paleomagnetic evidence

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Chinese Science bulletin 1997年第2期42卷 132-136页

作者： LI Zhengxiang, fang Dajun, Christopher McA. Powell and LOU Gang1. department of Geology and Geophysics, The {2. of Western Australia, Nedlands WA 6907, Australia 2. department of Earth sciences, Zhejiang {2., Hangzhou 31002., china department of Geology and Geophysics The University of Western Australia Nedlands Australia department of Earth sciences Zhejiang University Hangzhou China

THE South china Block exhibits a complex structural pattern in its Neoproterozoic-Mesozoic sedimentary cover. The lack of knowledge about the formation of this pattern hinders our understanding of the regional tectonic evolution and paleogeography, and the reconstruction of Phanerozoic apparent polar wander path(s). In this note we present a synthesis based on a paleomagnetic and tectonic analysis, which suggests that (i) the structural pattern over

关键词： Mesozoic paleomagnetism block rotation.

Calculation of the molecular exchanging energy of binary surfactants system on the surface monolayer of aqueous solution

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Science china Chemistry 2007年第4期50卷 468-475页

作者： WANG ZhengWu1 & yi XiZhang2.1 department of Food {2. & Technology, School of Agriculture and Biology, Shanghai Jiao Tong {2., Shanghai 2.02.0, china 2.Institute of Theoretical Chemistry, Shandong {2., Jinan 2.0100, china 1. department of Food sciences & Technology School of Agriculture and Biology Shanghai Jiao Tong University Shanghai 200240 China 2. Institute of Theoretical Chemistry Shandong University Jinan 250100 China

By using the binary anionic/cationic surfactants system CH3(CH2.nOSO_3/CH3(CH2.nN+(CH3)3 as an ex-ample, the molecular exchanging energy (ε) of adsorption on the surface monolayer of aqueous solu-tion has been studied. ε can be obtained with two methods. One is from the relationship between ε and the molecule interaction parameter (β). This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under which β can be obtained by testing the surface tension of solution. The other is directly from the molecular structure of surfactants with the Lennard-Jones formula. The results for the studied system show that these two methods coincide well.

关键词： surfactant molecule exchanging energy dimensional crystal model

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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Science china Chemistry 2004年第3期47卷 251-256页

作者： JIANG yinzhi1,2.& HU Weixiao1 1. department of Pharmaceutical Science, Zhejiang {2. of Technology, Hangzhou 310032.{2. 2. department of Applied Chemistry, Zhejiang Institute of Science and Technology, Hangzhou 310033,{2. 1. department of Pharmaceutical Science Zhejiang University of Technology 310032 Hangzhou China 2. department of Applied Chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yi)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

A new method for imaging faint objects nearby a bright source

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Chinese Science bulletin 2000年第3期45卷 201-207页

作者： YE Binxun & CHU yi1. Beijing Astronomical Observatory, Chinese Academy of sciences, Beijing 100012.{2. 2. NAOCAS, Beijing 100012.{2. 3. department of Astronomy, Nanjing university, Nanjing{2. Correspondence should be addressed to Ye Binxun Beijing Astronomical Observatory Chinese Academy of Sciences Beijing China NAOCAS Beijing China department of Astronomy Nanjing University Nanjing China

In astronomical observation, it is difficult to obtain the image of faint objects in the peripheral area around a bright celestial body. in order to solve the problem, a new method is designed and experimented, which is called the separation readout technique (SRT). SRT is different from either the traditional coronagraphy or the newly-developed anti-blooming CCD technique, and allows an enough-long exposure to the faint objects in the area around a bright celestial body with the well-preserved bright body’s image in one frame. This paper describes in detail the principle of SRT, the computer simulation, the experimental devising and result of SRT observation on a telescope.

关键词： astronomyical methods CCD imaging SRT.

Differential retardation of organic matter maturation by overpressure

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Science china Earth sciences 2004年第9期47卷 783-793页

作者： HAO fang1,2. JIANG Jianqun1, ZOU Huayao1, fang Yong1 & ZENG Zhiping2.1. Key Lab for Hydrocarbon Accumulation Mechanism in the Ministry of Education, Petroleum {2., Beijing 102.49, china 2. department of Petroleum Geology, china {2. of Geosciences, Wuhan 430074, china Key Lab for Hydrocarbon Accumulation Mechanism in the Ministry of Education Petroleum University Beijing 102249 China department of Petroleum Geology China University of Geosciences Wuhan 430074 China

The thermal evolution of organic matter (OM) is composed of a series of reactions that are paralell and successive with each other. Different reactions have different activation energy, different rates of product concentration variation, and different volume expansion effects, and therefore have different responses to overpressure, which determines the differential retardation of different OM maturation reactions and maturity parameters. Based upon comprehensive studies on the OM maturation in different pressure systems in the yinggehai, Qiongdongnan and Bohai Bay basins, 4 hierarchies of overpressure retardation have been recognized. (1) OM maturation in all aspects has been retarded by overpressure. (2. The thermal evolution of hydrocarbons and thermal degradation of hydrogen-rich kerogens has been retarded, but the thermal evolution of hydrogen-poor kerogen components has not been affected by overpressure. As a result, vitrinite reflectance has not been retarded. (3) The thermal cracking of hydrocarbons has been retarded, yet overpressure has had little or no effect on thermal degradation of kerogens. (4) Overpressure has no detectable effect on all aspects of OM maturation. The hierarchy that overpressure has retarded all aspects of OM maturation is the combined result of early overpressure (overpressure began to develop when the source rock was still immature) and the protracted maintenances of closed fluid system. Any case that overpressure had developed too late, or overpressure was too small to reach the threshold values, or overpressured fluid had been frequently released, could give rise to the occurrence of state 4 that overpressure had no detectable effect on all aspects of OM maturation. It seems that in many basins, overpressure retardation of hierarchies 2.and 3 developed where the most commonly used maturity parameter, vitrinite reflectance, had not been affected. In theses cases, multiple parameters must be used to distinguish overpressure retardati

关键词： overpressure, organic matter maturation, hydrocarbon generation, differential retardation.

Measurement and simulation of the two-phase velocity correlation in sudden-expansion gas-particle flows

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Acta Mechanica Sinica 2011年第4期27卷 494-501页

作者： Li-Xing Zhou.Yang Liu.yi Xu department of Engineering Mechanics,{2. {2.,100084 Beijing,china Marine Engineering College,Dalian Maritime {2.,11602. Dalian,china department of Engineering Mechanics Tsinghua University Beijing China Marine Engineering College Dalian Maritime University Dalian China

In this paper the present authors measured the gas-particle two-phase velocity correlation in sudden expansion gas-particle flows with a phase Doppler particle anemometer （PDPA） and simulated the system behavior by using both a Reynolds-averaged Navier-Stokes （RANS） model and a large-eddy simulation （LES）. The results of the measurements yield the axial and radial time-averaged velocities as well as the fluctuation velocities of gas and three particle-size groups （30μm, 50μm, and 95μm） and the gasparticle velocity correlation for 30μm and 50μm particles. From the measurements, theoretical analysis, and simulation, it is found that the two-phase velocity correlation of sudden-expansion flows, like that of jet flows, is less than the gas and particle Reynolds stresses. What distinguishes the two-phase velocity correlations of sudden-expansion flow from those of jet and channel flows is the absence of a clear relationship between the two-phase velocity correlation and particle size in sudden-expansion flows. The measurements, theoretical analysis, and numerical simulation all lead to the above-stated conclusions. Quantitatively, the results of the LES are better than those of the RANS model.

关键词： PDPA measurement - Simulation Two-phasevelocity correlation Sudden expansion gas-particle flows