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Impact analysis of different axis layouts of detached breakwater on flow and sediment transport

ARABIAN JOURNAL OF GEOSCIENCES 2021年第8期14卷 1-11页

作者： Yu, Haitao Luo, feng Li, Ruijie Liu, Yanran Fang, xuwen Li, Yuting Hohai Univ Minist Educ Key Lab Coastal Disaster & Def Nanjing 210098 Peoples R China Hohai Univ Coll Harbour Coastal & Offshore Engn Nanjing 210098 Peoples R China Hohai Univ Coll Oceanog Nanjing 210098 Peoples R China Nanjing Environm Monitoring Ctr Nanjing 210098 Peoples R China Xiamen Univ Marine Monitoring & Informat Serv Ctr Xiamen 361005 Peoples R China Nanjing Normal Univ Key Lab Virtual Geog Environm Nanjing 210023 Peoples R China

An incorporation and application of a two-dimensional, unstructured grid hydrodynamic model with a suspended sediment transport module is presented in the study. The model has a satisfactory verification with available measured data. After the verification, the variation of tidal current field and the seabed evolution are simulated. Based on the simulation results, the paper compares and analyzes the effects of different axis layouts of detached breakwater on flow field and seabed evolution. The results show that after the construction of the breakwater, the flow velocity of the both sides of the breakwater decreases, the flow velocity of the east entrance increases, and the erosion and siltation of sediment are consistent with the change of the flow field. In addition, the smaller the angle between the breakwater axis and the depth contour is, the smaller the impact on the change of the tidal current field and sediment erosion and siltation is.

关键词： Detached breakwater Axis layout Flow and sediment transport Hydrodynamic model

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ISAR Imaging Based on Block Sparse Smoothed L0 Norm Recovery Algorithm 2

ISAR Imaging Based on Block Sparse Smoothed L0 Norm Recovery...

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2019 2nd International Conference on Advanced Algorithms and Control Engineering, ICAACE 2019

作者： feng, Junjie Zhang, xuwen Wang, Yonghui School of Electrical Engineering Liupanshui Normal University Liupanshui GUIZHOU553004 China College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing211106 China

In order to obtain high resolution inverse synthetic aperture radar (ISAR) sparse images, a block sparse signal recovery ISAR imaging algorithm is proposed by considering the cluster characteristics of target in this paper. Firstly, the ISAR sparse imaging model is established, the imaging is converted to L0 norm optimization problem. Secondly, one negative exponential function sequence is used as smoothed function to approach the block L0 norm. Finally, the revised step is added to ensure solving the optimization problem along the steepest descent gradient direction and the cost function is updated for the next loop. Simulation results verify the proposed algorithm is effective. © Published under licence by IOP Publishing Ltd.

关键词： Inverse synthetic aperture radar

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Discovering Dependence across Traffic Data of Disparate Regions Using Multiscale Generalized Correlation 2018

Discovering Dependence across Traffic Data of Disparate Regi...

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6th International Conference on Information Technology - IoT and Smart City (ICIT)

作者： Qiu, Dehong Zhang, Pin Fang, Shaohong Lang, xuwen feng, Hao Huazhong Univ Sci & Technol Sch Software Engn Wuhan Hubei Peoples R China Wuhan Coll Sch Informat Engn Wuhan Hubei Peoples R China

ISBN: (纸本)9781450366298

Deciphering potential associations between the traffic data of disparate regions is of great importance to urban traffic management. However, as the traffic data is structured, temporal and often high-dimensional, many traditional dependence testing approaches are not directly applicable. In this paper, we propose a new approach to test dependence between traffic data of disparate regions based on distance Correlation (dCorr) and Multiscale Generalized Correlation (MGC). The distance matrix between the structured traffic data of disparate regions is defined, which yields a consistent test statistic for testing dependence of traffic data. We conduct experiments on the real and simulated datasets. The results of our experiments demonstrate that the new approach can capture the complex dependence between the structured traffic data of disparate regions. Simultaneously, it requires a small number of samples and is computationally efficient.

关键词： Traffic management network dependence graph distance distance correlation multiscale generalized correlation

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In-Situ Transformed Ni, S-Codoped CoO from Amorphous Co-Ni Sulfide as an Efficient Electrocatalyst for Hydrogen Evolution in Alkaline Media

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ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2019年第14期7卷 12501-12509页

作者： Lu, Wangting Li, xuwen Wei, feng Cheng, Kun Li, Wenhui Zhou, Youhua Zheng, Wanquan Pan, Lei Zhang, Geng Jianghan Univ Inst Interdisciplinary Res 8 Sanjiaohu Rd Wuhan 430056 Hubei Peoples R China Jianghan Univ Sch Chem & Environm Engn 8 Sanjiaohu Rd Wuhan 430056 Hubei Peoples R China Univ Paris Saclay Univ Paris Sud CNRS Inst Sci Mol Orsay F-91405 Orsay France Jianghan Univ Sch Life Sci 8 Sanjiaohu Rd Wuhan 430056 Hubei Peoples R China Huazhong Agr Univ Coll Sci Dept Chem 1 Shizishan St Wuhan 430070 Peoples R China

Amorphous materials have recently received much attention as catalysts for electrochemical reactions. However, there are relatively few reports focused on the structure change of amorphous catalysts during the catalysis process, although this is quite important to the identification of active species and in revealing the reaction mechanism. Herein, amorphous Co-Ni sulfide in the form of a nanoplate and nanowire hybrid on the surface of nickel foam is prepared as the electrode for the hydrogen evolution reaction (HER). During the hydrogen evolution process, the amorphous Co-Ni sulfide is in-situ transformed into crystalline Ni, S-co-doped CoO which is actually responsible for the catalysis of HER The transformation process is studied in detail by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and theoretical calculations. The in-situ formed electrode presents a high activity and durability toward HER in alkaline media. The Ni and S dopants, sulfurization temperature, and electrode substrate are revealed to be important factors that affect the activity. The present work will not only give more insights in the structure evolution of the electrocatalyst during HER but also provides a new strategy to the fabrication of new electrocatalysts.

关键词： Water splitting HER Amorphous material Oxide Doping

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Fast sulfurization of nickel foam-supported nickel-cobalt carbonate hydroxide nanowire array at room temperature for hydrogen evolution electrocatalysis

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ELECTROCHIMICA ACTA 2019年 318卷 252-261页

作者： Lu, Wangting Li, xuwen Wei, feng Cheng, Kun Li, Wenhui Zhou, Youhua Zheng, Wanquan Pan, Lei Zhang, Geng Jianghan Univ Inst Interdisciplinary Res Wuhan 430056 Hubei Peoples R China Jianghan Univ Sch Chem & Environm Engn Wuhan 430056 Hubei Peoples R China Univ Paris Saclay Univ Paris Sud Inst Sci Mol Orsay CNRS F-91405 Orsay France Jianghan Univ Sch Life Sci Wuhan 430056 Hubei Peoples R China Huazhong Agr Univ Coll Sci Dept Chem Wuhan 430070 Hubei Peoples R China

Transition metal sulfide is considered as a kind of promising noble metal-free material for hydrogen evolution reaction (HER). However, most of conventional sulfurization methods require high temperature and/or long reaction time. Herein, a sulfurization strategy at room temperature (25 degrees C) by using Na2S in aqueous solution is applied to sulfurize nickel foam-supported nickel-cobalt carbonate hydroxide nanowire array, during which amorphous sulfide gradually forms on the surface of nanowire and finally replaces the nanowire completely. It is found that the electrode sulfurized for 5 min in which only a thin sulfide layer is formed presents nearly identical catalytic performance for HER with the electrode that is sufficiently sulfurized for 120 min. The electrode sulfurized at 25 degrees C for 5 min only needs an overpotential of 100 mV to achieve hydrogen evolution current at 10 mA cm(-2) in 1 M KOH, and negligible loss of activity is observed after working at a current density of 20 mA cm(-2) for 25 h. The interface between carbonate hydroxide and sulfide is considered to play an important role in the catalysis of HER. The observation in this work can provide new insights into the sulfurization process and the role of sulfide in the process of HER. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： HER Sulfide Amorphous Interface DFT

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Development of a Synthesis Process for a Novel HCV NS5A Inhibitor, Emitasvir

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ORGANIC PROCESS RESEARCH & DEVELOPMENT 2021年第4期25卷 838-848页

作者： Xie, Hongming Liu, Haiwang Zhang, Yingjun Huang, Enhuo feng, Yahui Xiang, xuwen Fang, Qinghong Peng, Zhihong Dong, Wanrong An, Delie Hunan Univ Coll Chem & Chem Engn State Key Lab Chemo Biosensing & Chemometr Changsha 410082 Hunan Peoples R China Sunshine Lake Pharma Co Ltd State Key Lab Antiinfect Drug Dev 2015DQ780357 Dongguan 523871 Peoples R China HEC Pharm Grp HEC Res & Dev Ctr Dongguan 523871 Peoples R China

A new approach to the synthesis of Emitasvir (DAG181), a small molecule hepatitis C virus (HCV) nonstructural protein 5A (NS5A) inhibitor, is described. Enantioselective enzymatic desymmetrization with hydrolases in the synthetical approach can significantly avoid the loss of chiral raw materials in the resolution process. The synthesis route is further optimized and scaled-up to establish a new process that is applied to the preparation of kilogram scales of target active pharmaceutical ingredients (APIs). Compared with our initial process, the overall yield of target API was dramatically improved from 17 to 40%.

关键词： hepatitis C virus inhibitor Emitasvir enantioselective synthesis process development

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热带海洋大气环境下道岔扣件关键零部件锈蚀机理研究

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高速铁路新材料 2025年第1期4卷 7-13页

作者：徐超王晨阳胡莲俊刘甜甜王玉婷张倩孙旭文冯博宇杨其全中国铁道科学研究院集团有限公司金属及化学研究所北京100081 海南铁路有限公司海口综合维修段海口570300 北京中铁科新材料技术有限公司北京100081

为分析热带海洋气候下道岔弹条和T型螺栓的锈蚀机理及影响因素,对海南岛某高铁线路上现场抽取的锈蚀扣件进行了宏观形貌观察,光学显微镜和扫描电子显微镜微观组织、锈蚀层的化学成分能谱和XRD物相检测分析。结果表明:高湿热、高盐雾气... 详细信息

为分析热带海洋气候下道岔弹条和T型螺栓的锈蚀机理及影响因素,对海南岛某高铁线路上现场抽取的锈蚀扣件进行了宏观形貌观察,光学显微镜和扫描电子显微镜微观组织、锈蚀层的化学成分能谱和XRD物相检测分析。结果表明:高湿热、高盐雾气候条件与微动磨损致防锈涂层脱落、缝隙腐蚀等服役条件综合作用于扣件表面,使某些部位发生了较快的电化学腐蚀,生成α-FeOOH、γ-FeOOH和Fe_(3)O_(4)等锈蚀产物,锈层为存在孔洞和缝隙的疏松组织,难以为基体提供有效保护。对于已经没有有效防腐涂层的服役扣件,应及时替换为具有更强结合力及抗腐蚀性能的涂覆工艺的扣件;在铁路巡检中应对扣件朝向地面及与垫板接触的隐蔽位置进行重点观测。

关键词：弹条 T型螺栓锈蚀机理影响因素热带海洋气候

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Strong positive allosteric cooperativity in ternary complexes based on hydrogen-bonded aromatic amide macrocycles

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CHEMICAL COMMUNICATIONS 2019年第33期55卷 4869-4872页

作者： Peng, Zhiyong Guo, xuwen Xu, Weitao Li, Jian Deng, Pengchi Xiao, Xin feng, Wen Yuan, Lihua Sichuan Univ Analyt & Testing Ctr Minist Educ Coll ChemKey Lab Radiat Phys & Technol Chengdu 610064 Sichuan Peoples R China Guizhou Univ Key Lab Macrocycl & Supramol Chem Guizhou Prov Guiyang 550025 Guizhou Peoples R China

Three new hydrogen-bonded aromatic amide macrocycles with eight residues were synthesized. The first single crystal structure of this class of larger macrocycles was obtained, which reveals a saddle-like conformation. Interestingly, in sharp contrast to previous negative cooperativity in binding paraquat with cyclo[6]aramide, strong positive allosteric cooperativity in ternary complexes was observed. This may open an avenue for the construction of mechanically interlocked molecules with these larger H-bonded macrocycles.

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Deep Reinforcement Learning Home Energy Management Based Local Energy Trading in a Blockchain Platform 9

Deep Reinforcement Learning Home Energy Management Based Loc...

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9th Asia Conference on Power and Electrical Engineering, ACPEE 2024

作者： Jiang, Yu feng, Yingchun Fan, Jie Gao, Bo Wang, Yang Liu, xuwen Jiangsu Electric Power Trading Center State Grid Jiangsu Electric Power Co. LTD Nanjing China

ISBN: (纸本)9798350309638

Decentralized peer-to-peer Local Energy Markets (LEMs) are gaining popularity as local power production from Renewable Energy Sources (RESs) increases. The study investigates a blockchain-driven LEM in which prosumers and consumers buy and sell energy independently of the involvement of a third party. The suggested scheme involves Home Energy Management (HEM) and demurrage mechanisms that enable both consumers and prosumers to reduce their power prices and improve their power usage. The end-user can likewise move the load to off-peak periods and benefit from lower energy costs from the LEM through the approach. In this solution, HEM and demurrage mechanisms are used to optimize power usage as well as energy costs. As well as providing adequate power for the LEM, it is economically beneficial for end users and the community. The proposed system in the study utilizes the Deep Deterministic Policy Gradient (DDPG) algorithm and demurrage mechanisms to optimize electricity usage and energy costs. Meanwhile, smart contract on the Ethereum blockchain regulate and safeguard the electricity trading process. © 2024 IEEE.

关键词： Blockchain

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Steroidal saponins from Allium chinense and their inhibitory effects on pancreatic lipase

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PHYTOCHEMISTRY LETTERS 2023年 55卷 22-29页

作者： Xie, Huili Shi, Xiaolei Wang, Bingzi Zhao, Dexin Sun, Zhiheng Chen, Yifu feng, Yuezhu Jin, Yongri Li, xuwen Jilin Univ Coll Chem Changchun 130012 Peoples R China Jilin Univ Coll Food Sci & Engn Changchun 130062 Peoples R China

Allium chinense *** is an important medicinal and edible homologous plant and indigenous to China and grown in other countries. Phytochemical studies have shown that it is rich in biologically active natural products. Herein, five new and twelve known steroidal saponins were isolated from the bulbs of Allium chinense ***. These compounds were structurally determined by analysis of their NMR, IR and HR-ESI-MS data. All isolates were evaluated for inhibition of porcine pancreatic lipase activity. Compounds 4, 7 and 10 exhibited potent inhibition of porcine pancreatic lipase. The relationship between structure and activity of these compounds is also investigated in this paper.

关键词： Allium chinense Steroidal saponins Extraction and isolation Structure identification Lipase inhibitory activity

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