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Gas Phase Thermodynamic Properties of Polychlorinated Xanthones Predicted with DFT Method and Cl Substituted Position

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Chinese Journal of Chemical Engineering 2010年第3期18卷 462-471页

作者：陈建挺刘辉费艾莉程维明王遵尧 State Key Laboratory of Pollution Control and Resources Reuse School of Environment Nanjing University Nanjing 210093 China School of Environmental and Safety Engineering Jiangsu Polytechnic University Changzhou 213164 China School of Biological and Chemical Engineering Jiaxing University Jiaxing 314001 China U.S. Fulbright Student Grantee School of Social and Behavioral Sciences Nanjing University Nanjing 210093 China Chery Automobile Co. Ltd Wuhu 214006 China

The gas phase thermodynamic properties of 135 polychlorinated xanthones(PCXTs)are calculated using a combination of quantum mechanical computations performed with the Gaussian 03 program at the B3LYP/6-311G***** is found that the chlorine substitution pattern strongly influences the thermodynamic properties of the *** thermodynamic properties of congeners with the same number of chlorines also depend on the chlorine substitution pattern,especially for ortho-substituted *** congeners with one phenyl ring fully chlorinated are found to be the least stable among the *** effect of the chlorine substitution pattern is quantitatively studied by considering the number and position of Cl atom substitution(NPCS).The results show that the NPCS model may be used to predict the thermodynamic properties for all 135 PCXT congeners. In addition,the values of molar heat capacities at constant pressure(cp,m)from 200 to 1000 K for PCXT congeners are calculated,and the temperature dependence relation of this parameter is obtained using the least-squares method.

关键词： polychlorinated xanthones density functional theory number and position of Cl atom substitution thermodynamic property relative stability

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Second-order sensitivity of eigenpairs in multiple parameter structures

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Applied Mathematics and Mechanics(English Edition) 2009年第12期30卷 1475-1487页

作者：陈塑寰郭睿孟广伟 College of Mechanical Science and Engineering Nanling CampusJilin University State Key Laboratory of Automobile Dynamic Simulation Nanling CampusJilin University

This paper presents methods for computing a second-order sensitivity matrix and the Hessian matrix of eigenvalues and eigenvectors of multiple parameter structures. Second-order perturbations of eigenvalues and eigenvectors are transformed into multiple parameter forms,and the second-order perturbation sensitivity matrices of eigenvalues and eigenvectors are *** these formulations,the efficient methods based on the second-order Taylor expansion and second-order perturbation are obtained to estimate changes of eigenvalues and eigenvectors when the design parameters are changed. The presented method avoids direct differential operation,and thus reduces difficulty for computing the second-order sensitivity matrices of eigenpairs.A numerical example is given to demonstrate application and accuracy of the proposed method.

关键词： multiple parameter structures second-order sensitivity of eigenpairs efficient computational method

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A method of bearing fault feature extraction based on improved wavelet packet and hilbert analysis

International Journal of Digital Content Technology and its ...

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International Journal of Digital Content Technology and its Applications 2010年第4期4卷 127-139页

作者： Yang, Jian-wei Yao, De-chen Cai, Guo-qiang Liu, Hai-bo Zhang, Jiao School of Mechanical-electronic and Automobile Engineering Beijing University of Civil Engineering and Architecture Beijing 100044 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China School of Machine-electricity Engineering Taiyuan University of Science and Technology Taiyuan Shanxi 030024 China

In order to supply a gap of current resonance vibration and STFT demodulation method applied to rolling bearing fault feature extraction of city rail vehicle, a fault diagnosis method for rolling bearing is presented, which is based on the integration of improved wavelet packet, frequency energy analysis and Hilbert marginal spectrum. When faults occur in rolling bearing, the energy of the rolling bearing vibration signal would change correspondingly, while the Hilbert energy spectrum can exactly provide the energy distribution of the signal in certain frequency with the change of the time and frequency. Thus, the fault information of the rolling bearing can be extracted effectively from the improved wavelet packet and Hilbert energy spectrum. The experimental result proves that the fault characteristic extracted by improved wavelet packet and Hilbert transform is in accord with the one analyzed from theory, and the fault feature extraction method is effective. The research results provide the theoretical foundation for the extraction of fault feature in rotary machine and have important practical value.

关键词： Roller bearings

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Zoning Abrupt Environmental Pollution Risk in a Mega-city

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Procedia Environmental Sciences 2010年 2卷 1022-1031页

作者： R.Z. Liu D.D. Lan Alistair G.L. Borthwick State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China National Marine Environmental Monitoring Center Dalian 116023 China Department of Engineering Science Oxford University Parks Rd. Oxford OX1 3PJ U.K

Major abrupt environmental pollution accidents can cause huge socio-economic losses and seriously damage the environment. Zoning of abrupt environmental pollution risk can greatly aid decision-making and governance, with a view to preventing and mitigating such pollution accidents in a typical mega-city. The present paper proposes a risk system for environmental pollution accidents, which comprises an index system and a quantitative risk assessment model of environmental risk zonation. The system is based on data on past abrupt environmental pollution accidents, regional environmental risk theories, and natural disaster risk theories. An Abrupt Environmental Pollution Risk Zonation (AEPRZ) approach, applicable to a large area, is proposed, which involves the selection of appropriate zonation principles, units, and indexes for the measurement and classification of environmental risk, amending the zonation, and then mapping risk zonation with GIS tools. The AEPRZ approach is applied to the risk zonation of environmental pollution accidents in Minhang District, Shanghai, China, which was divided into four zones according to high, medium, low, and very low degrees of risk. In each zone, each of the socio-economic, hazard, vulnerability, and overall risk factors is assigned a specific degree of risk, thus providing a basis for the implementation of control measures as part of environmental risk prevention management.

关键词： Risk Abrupt Environmental Pollution Measuring Model Assessment Zonation

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Automated manual transmission shift strategy for parallel hybrid electric vehicle

Automated manual transmission shift strategy for parallel hy...

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作者： Wang, Weihua Wang, Qingnian Zeng, Xiaohua State Key Laboratory of Automobile Dynamic Simulation Jilin University China

For the parallel hybrid electric vehicles in which there are one engine and one motor, and the motor is located before the transmission, the motor torque is added as a new parameter to develop a new shift strategy for automated manual transmissions. The design rule of the shift strategy is to pursue a better fuel economy without sacrificing performance of the vehicle. Upshift strategies in four driving modes and downshift strategies in driving mode and in braking mode are discussed in detail respectively. simulations show that the new three-parameter shift strategy is able to save fuel consumption in driving mode and regenerate more energy in braking mode. Copyright © 2009 SAE International.

关键词： Fuel economy

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Pseudo-excitation method and its application to vehicle ride comfort

Pseudo-excitation method and its application to vehicle ride...

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作者： Jie, Li Yuying, Qin Qi, Zhao State Key Laboratory of Automobile Dynamic Simulation Jilin University China

Based on seven degree of freedom vibration model of truck, pseudo road excitation is constructed with pseudo-excitation method. System frequency response of vehicle is deduced by pseudo relationship between road excitation and vehicle responses. Pseudo responses of vehicle and pseudo vibration response variables of vehicle are built, and the method of statistical characteristics for real vibration response variables is given by pseudo vibration response variables. The result shows that pseudo-excitation method is better than Fourier method. Copyright © 2009 SAE International.

关键词： Vehicles

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Optimization of Vehicle Side Curtain Airbag Module Based on Computer Aided Engineering

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 521-527页

作者： ZHANG Junyuan LI Dongjun BI Ying YANG Donglin QIU Feng The State Key Laboratory of Automobile Dynamic Simulation Jilin University Changchun 130025 China Jinheng Automotive Safety System Co. Ltd. Jinzhou 121007 China

Compared with other kinds of airbags, curtain airbag（CAB） has more complex structures and larger coverage area. The product development process depends on many module tests, sled tests and full size vehicle tests. Computer aided engineering（CAE） technology can replace tests to a great extent, also save test costs and product development time. This paper introduces the way of setting up simulation models and application of static deployment tests and free motion headform（FMH） tests to verify simulation models. In the CAB simulation, uniform pressure airbag models and computational fluid dynamics（CFD） models are all used. The uniform pressure airbag models are not able to simulate the pressure difference among different parts inside the cushion during inflating process. CFD-based CAB models are used to help the curtain airbag optimization design. Based on effective CAE simulation, the optimization analyses related to diffuser tube parameters, inflator mass flow rate and cushion folding patterns are discussed and performed in different cases. The optimization result shows that the proposed techniques are helpful to the parametric optimization design of side curtain airbag module in curtain airbag development process.

关键词： curtain airbag Computer aided engineering simulation optimization

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Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

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Frontiers of Environmental Science & Engineering 2009年第3期3卷 313-319页

作者： Jiajun CHEN Hao WANG Na ZHANG State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China

This investigation was carried out to establish a new domestic landfill gas(LFG)generation rate model that takes into account the impact of leachate *** first-order kinetics and two-stage reaction(FKTSR)model of the LFG generation rate includes mechanisms of the nutrient balance for biochemical reaction in two main *** this study,the FKTSR model was modified by the introduction of the outflow function and the organic acid conversion coefficient in order to represent the in-situ condition of nutrient loss through *** experiments were carried out to simulate the impact of leachate recirculation and verify the modified FKTSR *** model calibration was then calculated by using the experimental *** results suggested that the new model was in line with the experimental *** main parameters of the modified FKTSR model,including the LFG production potential(L0),the reaction rate constant in the first stage(K1),and the reaction rate constant in the second stage(K2)of 64.746 L,0.202 d^(–1),and 0.338 d^(–1),respectively,were comparable to the old ones of 42.069 L,0.231 d^(–1),and 0.231 d^(–1).The new model is better able to explain the mechanisms involved in LFG generation.

关键词： landfill gas(LFG) generation rate model first-order kinetics two-stage reaction outflow function

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Measurement method of formaldehyde and unburned methanol emissions from a methanol engine

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Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and Technology Edition) 2010年第SUPPL.1期40卷 119-122页

作者： Li, Jun Gong, Chang-Ming Wang, Zhong Yu, Xiu-Min Liu, Xun-Jun State Key Laboratory of Automobile Dynamic Simulation Jilin University Changchun 130022 China Research and Development Center China First Automobile Works Group Corporation Changchun 130011 China United Automotive Electronic Systems Co. Ltd. Shanghai 201206 China

The objective of this investigation is to design sampling system of collecting exhaust emission by sampling bag and absorbing formaldehyde and unburned methanol in exhaust emission with pure water, to establish measurement system in which combine with gas chromatography and liquid chromatography to separate and measure formaldehyde and unburned methanol emissions, and to measure formaldehyde and unburned methanol emission during cold start by using this measurement method from a inlet port fuel injection spark-ignition methanol engine by means of cycle-by-cycle control strategy. The results show that the combination method of gas chromatography and liquid chromatography may separate and measure the formaldehyde and unburned methanol emission effectively. The detection limits of formaldehyde and methanol for gas chromatography are 0.16μg/mL and 0.18μg/mL, respectively, and the detection limits of methanol is 0.15μg/mL for liquid chromatography. This measurement method can satisfy measurement requirement for formaldehyde and unburned methanol of methanol engine.

关键词： Formaldehyde

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Effects of allelochemical gramine on photosynthetic pigments of cyanobacterium microcystis aeruginosa

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World Academy of Science, Engineering and Technology 2010年 71卷 830-834页

作者： Hong, Y. Hu, H.Y. Sakoda, A. Sagehashi, M. College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China Environmental Simulation and Pollution Control State Key Joint Laboratory Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Institute of Industrial Science University of Tokyo Tokyo 1068558 Japan Institute of Industrial Science University of Tokyo Tokyo 1068558 Japan

Toxic and bloom-forming cyanobacterium Microcystis aeruginosa was exposed to antialgal allelochemical gramine (0, 0.5, 1, 2, 4, 8 mg·L-1), The effects of gramine on photosynthetic pigments (lipid soluble: chlorophyll a and β-carotene;water soluble: phycocyanin, allophycocyanin, phycoerythrin, and total phycobilins) and absorption spectra were studied in order to identify the most sensitive pigment probe implicating the crucial suppression site on photosynthetic apparatus. The results obtained indicated that all pigment parameters were decreased with gramine concentration increasing and exposure time extending. The above serious bleaching of pigments was also reflected on the scanning results of absorption spectra. Phycoerytherin exhibited the highest sensitivity to gramine added, following by the largest relative decrease. It was concluded that gramine seriously influenced algal photosynthetic activity by destroying photosynthetic pigments and phycoerythrin most sensitive to gramine might be contributed to its placing the outside of phycobilins.

关键词： Water absorption

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