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Studies on the Quantitative Structure-activity Relationship of Toxicity of Chlorophenol Serial Compounds in the ab initio Methods and Substitutive Position of Chlorine Atom (N_(PCS))

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Chinese Journal of Structural Chemistry 2007年第8期26卷 933-938页

作者： ZHENG Qing WANG lian-sheng Chemistry ＆ Bioengineering College Yancheng Institute of Technology Yancheng Jiangsu 224003 China School of the Environment Nanjing University Nanjing Jiangsu 210093 China

20 Quantum chemical parameters of chlorophenol compounds were fully optimized by using B3LYP method on both 6-31G^＊ and 6-311G^＊ basis sets. These structural parameters are taken as theoretical descriptors, and the experimental data of 20 compounds＇ aquatic photogen toxicity（-lgEC50） are used to perform stepwise regression in order to obtain two predicted -lgEC50 correlation models whose correlation coefficients R^2 are respectively 0.9186 and 0.9567. In addition, parameters of chlorine atom＇s substitutive positions and their correlations （NPCs） are taken as descriptors to obtain another predicted -lgEC50 model with the correlation coefficient R2 of 0.9444. Correlation degree of each independent variable in the three models is verified by using variance inflation factors （VIF） and t value. In the cross-validation method, cross-validation coefficients q^2 of 3 models are respectively 0.8748, 0.9119 and 0.8993, which indicates that the relativity and prediction ability of this model are superior to those of the model obtained by topological and BLYP methods.

关键词： chlorophenol toxicity (-lgEC50) linear dissolving energy theory density functional theory (DFT) substitutive position of chlorine atom (NPCS) QSAR

Baishideng's century goal:Editing and publishing high-quality articles

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World Journal of Gastroenterology 2009年第31期15卷 3841-3844页

作者： lian-sheng Ma Beijing Baishideng BioMed Scientific Co. Ltd. Room 903 Building D Ocean International Center No. 62 Dongsihuan Zhonglu Chaoyang District Beijing 100025 China

Baishideng's goal over the next few years is to edit and publish high-quality articles through the open-access model, to maximize the benefits to members of the editorial board, authors and readers, as well as achievi... 详细信息

关键词： Access to information Baishideng Maximization of the personal benefit Editorial policies Open access Periodicals Publishing

The effect of phase angle and wing spacing on tandem flapping wings

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Acta Mechanica Sinica 2012年第6期28卷 1557-1571页

作者： Timothy M. Broering Yong-sheng lian Department of Mechanical Engineering University of Louisville

In a tandem wing configuration, the hindwing of- ten operates in the wake of the forewing and, hence, its per- formance is affected by the vortices shed by the forewing. Changes in the phase angle between the flapping motions of the fore and the hind wings, as well as the spacing between them, can affect the resulting vortex/wing and vortex/vortex interactions. This study uses 2D numerical simulations to in- vestigate how these changes affect the leading dege vortexes （LEV） generated by the hindwing and the resulting effect on the lift and thrust coefficients as well as the efficiencies. The tandem wing configuration was simulated using an incom- pressible Navier-Stokes solver at a chord-based Reynolds number of 5 000. A harmonic single frequency sinusoidal oscillation consisting of a combined pitch and plunge motion was used for the flapping wing kinematics at a Strouhal num- ber of 0.3. Four different spacings ranging from 0.1 chords to 1 chord were tested at three different phase angles, 0°, 90° and 180°. It was found that changes in the spacing and phase angle affected the timing of the interaction between the vor- tex shed from the forewing and the hindwing. Such an inter- action affects the LEV formation on the hindwing and results in changes in aerodynamic force production and efficiencies of the hindwing. It is also observed that changing the phase angle has a similar effect as changing the spacing. The re- suits further show that at different spacings the peak force generation occurs at different phase angles, as do the peak efficiencies.

关键词： Tandem. Flapping. Airfoils. Micro air vehicle.Caculational fluid dynamics (CFD) Overlapping grids

A Note on Weighted Composition Operators on the Weighted Bergman Space

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Acta Mathematica Sinica,English Series 2015年第6期31卷 947-952页

作者： lian Kuo ZHAO sheng Zhao HOU School of Mathematics and Computer Science Shanxi Normal University School of Mathematics Science Soochow University

This paper gives a note on weighted composition operators on the weighted Bergman space, which shows that for a fixed composition symbol, the weighted composition operators are bounded on the weighted Bergman space on... 详细信息

关键词： Weighted Bergman space weighted composition operator boundedness finite Blaschke product

Semivolatile organic compounds, organochlorine pesticides and heavy metals in sediments and risk assessment in Huaihe River of China

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Journal of Environmental Sciences 2006年第2期18卷 236-241页

作者： HUANG Hong OU Wen-hua WANG lian-sheng College of Marine Science and Technology Shanghai Fisheries University Shanghai 200090 China School of Environmental Science and Technology Tongji University Shanghai 200092 China College of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China

The concentrations of semivolatile organic compounds, organochlorine pesticides and heavy metals in sediments from Jiangsu reach of Huaihe River, China, were presented. The organic compounds were extracted by acetone： n-hexane using a Soxhlet apparatus and concentrations were performed using HP6890 gas chromatography coupled by FID and ECD detector. The total contents of 8 heavy metals by inductively coupled plasma atomic emission spectrometry or cold-vapor/atomic absorption spectrometry were developed. 30 semivolatile organic compounds were detected, including substituted benzenes, phenols, phthalates and polycyclic aromatic hydrocarbons, from 0.01 to 3.01 mg/kg. 16 organochlorine pesticides were almost detected and from 0.010 to 2.339 μg/kg. Concentrations of major metals were 50 mg/kg or less, mean level of mercury was only 0.055 mg/kg. Compared to sediment quality guidelines （SQGs）, concentrations of some semivolatilc organic compounds were high enough to cause possible toxic effects to living resources. The organochlorine pesticides presented relatively low, lower than threshold effect concentrations （TECs）, harmful effects on sediment-dwelling organisms were not expected. Chromium posed probable toxic effects to the living resources, other heavy metals had no threat temporarily according to SQGs.

关键词： sediment semivolatile organic compounds organochlorinc pcsticidcs heavy mctals sediment quality guiedlines Huaihe River

Optimizing the atmospheric sampling sites using fuzzy mathe-matic methods

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Journal of Environmental Sciences 2003年第4期15卷 464-468页

作者： FANG Chun sheng WANG Ju DONG De ming YU lian sheng College of Environment and Resources Jilin UniversityChangchun 130023China.

A new approach applying fuzzy mathematic theorems, including the Primary Matrix Element Theorem and the Fisher Classification Method, was established to solve the optimization problem of atmospheric environmental sampling sites. According to its basis, an application in the optimization of sampling sites in the atmospheric environmental monitoring was discussed. The method was proven to be suitable and effective. The results were admitted and applied by the Environmental Protection Bureau (EPB) of many cities of China. A set of computer software of this approach was also completely compiled and used.

关键词： fuzzy set primary matrix element theorem fisher classification method optimization of sampling sites

MEDV-13 for QSRR of 62 Polychlorinated Naphthalenes

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Chinese Chemical Letters 2002年第8期13卷 791-794页

作者： Shu Shen LIU Chun sheng YIN lian sheng WANG State Key Laboratory of Pollution Control and Resources Reuse Department of Environmental Science&EngineeringNanjing UniversityNanjing 210093

A molecular electronegativity distance vector based on 13 atomic types (MEDV-13) is used to describe the structures of 62 polychlorinated naphthalene (PCN) congeners and related to the gas chromatographic relative retention indices (RIs) of PCNs. Using multiple linear regression, a 4-variable quantitative structure-retention relationship (QSRR) with the correlation coefficient of estimations (r) being 0.9912 and the root mean square error of estimations (RMSEE) being 31.4 and the correlation coefficient of predictions (q) and the root mean square error of predictions (RMSEP) in the leave-one-out procedure are 0.9898 and 33.76, respectively.

关键词： Molecular electronegativity distance vector (MEDV) polychlorinated naphthalene (PCN) gas chromatographic relative retention indice (RI) multiple linear regression (MLR).

A NEW FILLED FUNCTION METHOD FOR INTEGER PROGRAMMING

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Journal of Computational Mathematics 2006年第1期24卷 25-32页

作者： Ming-ming Li You-lin Shang lian-sheng Zhang Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics Shanghai University of Engineering Science Shanghai 200336 China Department of Mathematics Henan University of Science and Technology Luoyang 471003 China

The Filled Function Method is a class of effective algorithms for continuous global optimization. In this paper, a new filled function method is introduced and used to solve integer programming. Firstly, some basic definitions of discrete optimization are given. Then an algorithm and the implementation of this algorithm on several test problems are showed. The computational results show the algorithm is effective.

关键词： Global minimization Integer programming Filled function method

A HYBRID MODEL FOR SIMULATING VELOCITY FIELD OF A RIVER WITH COMPLEX GEOMETRY PLUNGED BY MULTIPLE JETS

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Journal of Hydrodynamics 2006年第6期18卷 752-759页

作者： LI lian-xia LIAO Hua-sheng LI Tian-xiang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A hybrid model that combines both physical and numerical models was employed to simulate the velocity field in a river area in complex geometry with multiple plunging jets. The simulation was based on experiments concerning energy dissipation and scour prevention at the Xiluodu Hydropower Station on the Yangtze River. The calculated results indicate that the complex geometry of the river area has a significant influence on the velocity field, especially on the circulation flow pattern at upstream and downstream of the plunging area and on the asymmetric characteristics of the spiral flow near both banks. The scour characteristics of the downstream river bed caused by the multiple jets were also predicted and analyzed according to the characteristics of the calculated velocity field. The good agreement between the simulated and experimental results indicates that the hybrid model can be used to effectively solve complicated 3-D problems with complex geometric and inlet conditions. Such problems may not easily be solved by using either a physical or a numerical model alone, and therefore the method presented in this article is considered to be a practical and effective way of dealing with this kind of problems.

关键词： hybrid models turbulence model scour multiple jets