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Numerical Investigations on Hydrodynamic Performance of An Open Comb-Type Breakwater Under Medium Water Levels

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China Ocean Engineering 2021年第6期35卷 866-877页

作者： FANG Zhuo cheng liang ZANG Zhi-peng SHEN Chen TIAN Ying-hui cheng Ning Transport planning and Research Institute Ministry of TransportBeijing 100028China Laboratory for Traffic and Transport Planning Digitalization Beijing 100028China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116023China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Melbourne School of Engineering The University of MelbourneParkvilleVIC 3010Australia China Harbor Engineering Company Limited Beijing 100027China

The comb-type breakwater(CTB)has been proposed and investigated in recent years due to its advantages in terms of deep-water adaptability,material saving and water *** existing empirical formulae for CTBs have been so far restricted to the water level above the bottom of the superstructure,which mainly occurs under the high tides or storm ***,based on recent engineering applications and experimental observations,the most severe conditions for CTBs are more likely to occur under a medium water level,because impulsive wave pressure may occur due to interactions between waves and the special chamber in ***,during the most of construction and operation periods,the CTBs are mainly working under the medium water levels,i.e.,water levels below the bottom of the *** this study,the effects of main influence parameters on the horizontal wave force coefficient and wave transmission coefficient for open CTBs(with partially immersed side plates)under medium water levels were investigated based on a 3D numerical wave flume and corresponding empirical formulae were *** is indicated that the location of the side plate related to the main caisson has significant influence on the hydrodynamic performance of *** engineering applications,the location of the side plate can be designed at b/L≤0.15 or b/L≥0.3(where b is the distance between the side plate and the front face of the main caisson and L is the incident wave length)for efficiently lowering the horizontal wave force and wave *** flow mechanism of impulsive wave force on CTBs was revealed based on synchronous analyses of flow fields and pressure *** appropriate design of the height of the superstructure according to H/hD≤1.0 or H/hD≥1.5(where H is the incident wave height and hD is the distance between the still water level and the bottom of the superstructure),the likely impulsive wave pressure on the side plate can also be diminished.

关键词： numerical wave flume open comb-type breakwater horizontal wave force coefficient transmission coefficient medium water level

Assessment and mapping of environmental quality in agricultural soils of Zhejiang Province, China

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Journal of Environmental Sciences 2007年第1期19卷 50-54页

作者： cheng Jie-liang SHI Zhou ZHU You-wei Institute of Agricultural Remote Sensing and Information System Zhejiang University Hangzhou 310029 China Protection and Monitoring Station of Agricultural Environment Bureau of Agriculture Zhejiang Province Hangzhou 310020 China

Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samples were collected from 38 counties in Zbejiang Province and eight heavy metal （Cd, Cr, Pb, Hg, Cu, Zn, Ni and As） concentrations had been evaluated in agricultural soil. It was found 775 samples were unpolluted and 133 samples were slightly polluted and more respectively, that is approximately 14.65% agricultural soil samples had the heavy metal concentration above the threshold level in this province by means of Nemerow＇s synthetical pollution index method according to the second grade of Standards for Soil Environmental Quality of China （GB15618- 1995）. Contamination of Cd was the highest, followed by Ni, As and Zn were lower correspondingly. Moreover, Inverse Distance Weighted （IDW） interpolation method was used to make an assessment map of soil environmental quality based on the Nemerow＇s pollution index and the soil environmental quality was categorized into five grades. Moreover, ten indices were calculated as input parameters for principal component analysis （PCA） and the principal components （PCs） were created to compare environmental quality of different soils and regions. The results revealed that environmental quality of tea soils was better than that of paddy soils, vegetable soils and fruit soils. This study indicated that GIS combined with multivariate statistical approaches proved to be effective and powerful tool in the mapping of soil contamination distribution and the assessment of soil environmental quality on provincial scale, which is beneficial to environmental protection and management decision-making by local government.

关键词： agricultural soil heavy metals soil environmental quality Nemerow's synthetical pollution index multivariate analysis

An unprecedented synthesis of axially chiral biaryls by rearrangement and aromatization of carbocations with central-to-axial conversion of chirality

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Science China Chemistry 2024年第9期67卷 2998-3003页

作者： Qi Liu Xue-Dong Li liang cheng Li Liu Beijing National Laboratory for Molecular Sciences(BNLMS) CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The central-to-axial chirality conversion represents a fascinating class of chemical processes consisting of the destruction of stereogenic centers and the simultaneous installation of axial chiral elements,which provides efficient methods for the preparation of axially chiral ***,developing catalytic asymmetric approaches for constructing these central chirality precursors and the efficient central-to-axial chirality conversion remains a challenge due to the requirement of aromatization or elimination *** this work,we have developed an unprecedented enantioselective intramolecular FriedelCrafts alkylation with unactivated-ketone carbonyls from which a chiral tertiary alcohol was generated with high efficiency and excellent *** addition,the central-to-axial chirality conversion strategy has been successfully applied to the synthesis of enantioenriched biaryls via a less-explored carbocation-initiated rearrangement and aromatization under the promotion of Lewis *** methodology provided a straightforward and sustainable access to a broad range of biaryl-2-carboxylic acid and in excellent yields(up to 92%)and excellent central-to-axial chirality conversion(up to 99%conversion percentage).This work could be a great model for developing new methods for synthesizing axially chiral biaryls and a general protocol for the rearrangement and aromatization of carbocations for further functionalization.

关键词： br?nsted acid catalysis desymmetrization phosphoric acid axially chiral biaryls central-to-axial conversion

Energy management strategy for a parallel hybrid electric vehicle equipped with a battery/ultra-capacitor hybrid energy storage system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第8期14卷 535-553页

作者： Jun-yi liang Jian-long ZHANG Xi ZHANG Shi-fei YUAN cheng-liang YIN National Engineering Laboratory for Automotive Electronic Control Technology Shanghai Jiao Tong University

To solve the low power density issue of hybrid electric vehicular batteries, a combination of batteries and ultracapacitors (UCs) could be a solution. The high power density feature of UCs can improve the performance of battery/UC hybrid energy storage systems (HESSs). This paper presents a parallel hybrid electric vehicle (HEV) equipped with an internal combus- tion engine and an HESS. An advanced energy management strategy (EMS), mainly based on fuzzy logic, is proposed to improve the fuel economy of the HEV and the endurance of the HESS. The EMS is capable of determining the ideal distribution of output power among the internal combustion engine, battery, and UC according to the propelling power or regenerative braking power of the vehicle. To validate the effectiveness of the EMS, numerical simulation and experimental validations are carried out. The results indicate that EMS can effectively control the power sources to work within their respective efficient areas. The battery load can be mitigated and prolonged battery life can be expected. The electrical energy consumption in the HESS is reduced by 3.91% compared with that in the battery only system. Fuel consumption of the HEV is reduced by 24.3% compared with that of the same class conventional vehicles under Economic Commission of Europe driving cycle.

关键词： Energy management Fuel economy Parallel hybrid electric vehicle Hybrid energy storage system (HESS) Fuzzy logic

Potential for targeted therapy in prostate cancers with ERG abnormalities

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Asian Journal of Andrology 2011年第6期13卷 781-782页

作者： Sean R Williamson liang cheng Department of Pathology Indiana University School of Medicine Indianapolis IN 46202 USA Department of Urology Indiana University School of Medicine Indianapolis IN 46202 USA

Since the recent identification of recurrent gene fusions in prostate cancer betweenmembers of the ETS family of genes and transmembrane protease, serine 2 （TM PRSS2）, a tremendous amount of interest has developed in the pathways through which these fusions contribute to prostatic carcinogenesis, as well as their diaenostic utilitv.

关键词： identification recurrent gene fusions prostate cancer

A Monotonic Algorithm for Eigenvalue Optimization in Shape Design Problems of Multi-Density Inhomogeneous Materials

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Communications in Computational Physics 2010年第8期8卷 565-584页

作者： Zheng-fang Zhang Ke-wei liang Xiao-liang cheng Department of Mathematics Zhejiang UniversityHangzhou 310027China

Many problems in engineering shape design involve eigenvalue *** relevant difficulty is that the eigenvalues are not continuously differentiable with respect to the *** this paper,we are interested in the case of multi-density inhomogeneous materials which minimizes the least *** the finite element discretization,we propose a monotonically decreasing algorithm to solve the minimization *** numerical examples are provided to illustrate the efficiency of the present algorithm as well as to demonstrate its availability for the case of more than two *** the computations are sensitive to the choice of the discretization mesh sizes,we adopt the refined mesh strategy,whose mesh grids are 25-times of the amount used in[*** and ***,***.,171(2001),pp.272-288].We also show the significant reduction in computational cost with the fast convergence of this algorithm.

关键词： Multi-density inhomogeneous materials the least eigenvalue optimization problem finite element method monotonic algorithm

NUMERICAL SIMULATION AND COMPARISON OF WATER INTAKE-OUTLET METHODS IN POWER PLANTS

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Journal of Hydrodynamics 2007年第5期19卷 623-629页

作者： cheng You-liang YING Bo-fen School of Energy and Power Engineering North China Electric Power University Baoding 071003 China

The eclipsed form arrangement and march-past method of water intake-outlet arrangements in power plants were researched by 3-D numerical simulation based on the k-e two-equation turbulence model. Firstly, the flowing characteristics of eclipsed form arrangement were analyzed and the effects of some main factors on inlet temperature were investigated. The simulation results are basically in agreement with those of the previous experiments. Then, by comparing the inlet temperature of the above two intake-outlet methods, the superiority and its existent conditions of the eclipsed form were examined.

关键词： method water simulation eclipsed form arrangement,intake-outlet inlet temperature,march-past numerical

Entransy decrease principle of heat transfer in an isolated system

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Chinese Science Bulletin 2011年第9期56卷 847-854页

作者： cheng XueTao liang XinGang GUO ZengYuan Key Laboratory for Thermal Science and Power Engineering of Ministry of Education School of Aerospace Tsinghua University Beijing 100084China

The entropy increase principle for an isolated system and the criteria of thermal equilibrium for an isolated system and systems with prescribed temperature and volume can be derived on the basis of the concept of entropy and the first and second laws of thermodynamics. In this paper, the entransy decrease principle for an isolated system is introduced on the basis of the concept of entransy. It is found that the entransy of an isolated system always decreases during heat transfer. This principle can be taken as an expression of the second law of thermodynamics for heat transfer. The thermal equilibrium criteria for an isolated system and a closed system are also introduced. It is found that when an isolated system reaches thermal equilibrium, its entransy is a minimum value. This criterion is referred to as the minimum entransy principle. When a closed system reaches thermal equilibrium, its free entransy is also a minimum value. This criterion is referred to as the minimum free entransy principle. Therefore, like entropy, entransy can be considered an arrow of time in heat transfer and used to describe the thermal equilibrium state.

关键词：孤立系统传热原理热力学第二定律熵增加原理封闭系统平衡系统平衡条件时间箭头

Effects of Dan-shao-hua-xian on expression of PPAR-gamma and NF-kappa B in rat liver fibrosis

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Hepatobiliary & Pancreatic Diseases International 2008年第2期7卷 179-184页

作者： Wang, He-Yan cheng, Ming-liang Affiliated Hosp Guiyang Med Coll Dept Infect Dis Guiyang 550004 Peoples R China

BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPAR-gamma) and nuclear factor kappa B (NF-kappa B) play important roles in liver fibrosis. This study aimed to investigate the effects of Dan-shao-hua-xian, a preparation of traditional Chinese medicine, on the expression of PPAR-gamma and NF-kappa B in the fibrotic livers of rats. METHODS: Seventy Wistar rats were randomly divided into 4 groups: treatment (model, 8 weeks+treatment, 8 weeks; group A), natural recovery (model, 8 weeks+ saline, 8 weeks; group B), model (model only, 8 weeks; group Q, and control (normal, untreated, 16 weeks; group D). Each group consisted of 20 rats (except for group D, which had 10). Fibrotic liver models were induced in rats by subcutaneous injection of CCI4, oral administration of alcohol and a high-lipid/low-protein diet for 8 weeks. After the models were established, the rats in group A were orally given Dan-shao-hua-xian capsules daily for another 8 weeks. Then, the liver indices serum hyaluronic acid (HA), tumor necrosis factor-alpha (TNF-alpha) and alanine aminotransferase (ALT) were measured. The degree of hepatic fibrosis was evaluated by optical microscopy. Hydroxyproline (Hyp) in the liver tissue was determined. The expression of PPAR-gamma was detected by immunohistochemical techniques. The protein levels of PPAR-gamma and NF-kappa B were determined by Western blotting. RESULTS: The concentrations of serum HA, TNF-alpha and Hyp in group C increased compared with group D (P<0.05), and they decreased in group A compared with group C (P<0.05). The expression of PPAR-gamma in group C decreased compared with group D (P<0.05), and it increased in group A compared with groups B and C (P<0.05). Similarly, Western blotting showed that the expression of PPAR-gamma in group C decreased compared with group D, and it increased in group A compared with group C. The expression of NF-kappa B increased in group C compared with group D (P<0.05), and it decreased in group A compa

关键词： Dan-shao-hua-xian capsules peroxisome proliferator-activated receptors NF-kappa B hepatic fibrosis