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Chinese Journal of Chemistry 2013年第7期31卷 878-884页

作者： xiao shen Chuanfa Ni Jinbo Hu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A highly stereoselective synthesis of tetrasubstituted monofluoroalkenes with aldehydes and fluorobis（phenyl- sulfonyl）methane （FBSM） in one pot has been developed. The reaction was amenable topara- and meta-substituted aryl aldehydes, 2-naphthaldehyde, and cinnamaldehyde, giving phenylsulfonyl-substituted monofluoroalkenes in 40%--86% yields with 98/2- 99/1 Z/E ratios. The presence of the sulfonyl group enables the further transformation of the products into more useful monofluoroalkenes.

关键词： olefination aldehydes nucleophilic addition sulfones fluorine

Stereoselective formation of Z-monofluoroalkenes by nickel-catalyzed defluorinative coupling of gem‑difluoroalkenes with lithium organoborates

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Chinese Chemical Letters 2022年第9期33卷 4277-4280页

作者： Yisa xiao Weichen Huang Qilong shen Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

A method for stereoselective construction of Z-monofluoroalkenes by nickel-catalyzed defluorinative coupling of gem‑difluoroalkenes in mild conditions was *** combination of lithium organoborate and ZnBr_(2) generated in situ lithium aryl zincates,which facilitates the transmetalation step of the nickel-catalyzed cross coupling reaction.

关键词： gem‑Difluoroalkenes Lithium organoborate Defluorination Nickel Coupling

A self-optimizing QoS-aware service composition approach in a context sensitive environment

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第3期12卷 221-238页

作者： Yuan-hong shen xiao-hu YANG School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

QoS-aware service composition is aimed to maximize the global QoS of a composite service when selecting candidate *** a context sensitive service execution environment in pervasive computing,the context information for service composition is not static:device,policy,and user constraints,and QoS requirements may change,new services may be deployed,old ones withdrawn,or existing ones change their QoS *** results in the current service composition plan failing or its QoS degrading from the *** this paper,a runtime self-optimizing service composition framework is *** implementation of a prototype for this framework is presented,addressing the issues of reducing extra delay while increasing global QoS in service composition in a dynamic context *** service re-plan algorithms are compared that can be used in dynamic context environment,i.e.,minimal-conflict hill-climbing repair genetic algorithm(MCHC-repair GA),an improved penalty-based GA,and our multi-population conflicts sorted repair genetic algorithm(MP-CS-repair GA),as well as three kinds of service composition mechanisms-with backup,without backup,and our context-aware service re-selection *** results show that our MP-CS-repair GA and context-aware service re-selection method can reduce more extra delay while acquiring a higher global QoS for the composite service in a context sensitive *** context-aware service re-selection mechanism also shows some adaptability to different context change frequencies and user requirements for reducing computation cost in the self-optimizing process.

关键词： Service composition Quality of service(QoS) Context Repair genetic algorithm Self-optimizing

Discrete Numerical Study on Type II Fracture of Partially Detached Concrete Panels in Cold Region

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Structural Durability & Health Monitoring 2025年第1期19卷 167-191页

作者： Huayi Zhang Maobin Song Lei shen Nizar Faisal Alkayem Maosen Cao College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210024China Haihe River Huaihe River and Xiaoqinghe River Basin Water Conservancy Management and Service Center of Shandong ProvinceJinan250100China College of Mechanics and Engineering Science Hohai UniversityNanjing211100China

When the upper chord beam of the beam-string structure(BSS)is made of concrete-ﬁlled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the *** order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during con-struction,the inﬂuence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefﬁcient on the bending stiffness are analyzed parametrically by the numerical simula-tion technology based on an actual *** calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical ***,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction ***,the optimal construction plan of concrete placementﬁrst and then prestress-tensioning is proposed.

关键词： Beam-string structure(BSS) concrete-ﬁlled steel tube(CFST) bending stiffness timing of concrete placement prestress-tensioning

A Review of RGB-D Camera Calibration Methods

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Journal of Geodesy and Geoinformation Science 2021年第4期4卷 11-33页

作者： Chenyang ZHANG teng HUANG Yueqian shen School of Civil Engineering and Architecture Changzhou Institute of TechnologyChangzhou 213032China School of Earth Science and Engineering Hohai UniversityNanjing 211100China

RGB-D camera is a new type of sensor,which can obtain the depth and texture information in an unknown 3D scene simultaneously,and they have been applied in various fields *** fact,when implementing such kinds of applications using RGB-D camera,it is necessary to calibrate it *** the best of our knowledge,at present,there is no existing a systemic summary related to RGB-D camera calibration ***,a systemic review of RGB-D camera calibration is concluded as ***,the mechanism of obtained measurement and the related principle of RGB-D camera calibration methods are ***,as some specific applications need to fuse depth and color information,the calibration methods of relative pose between depth camera and RGB camera are introduced in Section *** the depth correction models within RGB-D cameras are summarized and compared respectively in Section ***,considering that the angle of the view field of RGB-D camera is smaller and limited to some specific applications,we discuss the calibration models of relative pose among multiple RGB-D cameras in Section *** last,the direction and trend of RGB-D camera calibration are prospected and concluded.

关键词： RGB-D camera calibration relative pose depth correction multiple RGB-D cameras

Physical neural networks with self-learning capabilities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 23-42页

作者： Weichao Yu Hangwen Guo Jiang xiao Jian shen State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China Department of Physics Fudan UniversityShanghai 200433China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Physical neural networks are artificial neural networks that mimic synapses and neurons using physical systems or *** networks harness the distinctive characteristics of physical systems to carry out computations effectively,potentially surpassing the constraints of conventional digital neural networks.A recent advancement known as“physical self-learning”aims to achieve learning through intrinsic physical processes rather than relying on external *** article offers a comprehensive review of the progress made in implementing physical self-learning across various physical *** learning strategies that contribute to the realization of physical self-learning are *** challenges in understanding the fundamental mechanism of learning,this work highlights the progress towards constructing intelligent hardware from the ground up,incorporating embedded self-organizing and self-adaptive dynamics in physical systems.

关键词： self-learning physical neural networks neuromorphic computing physical learning

Photocatalyzed[2+1]cyclization of alkenes and silylated trifluorodiazoethanes:facile entry into(difluoromethylene)cyclopropanes

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Science China Chemistry 2023年第11期66卷 3141-3147页

作者： Suo Chen Yizhi Zhang Shanshan Liu xiao shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China shenzhen Research Institute of Wuhan University Shenzhen 518057China

Methylenecyclopropanes are among the most robust building blocks in synthetic chemistry,but the study on(difluoromethylene)-cyclopropanes is rather limited,because of the difficulty in the synthesis of these ***,we report the invention of a novel carbene precursor,(1-diazo-2,2,2-trifluoroethyl)dimethyl(phenyl)silane(1a)and its application in the synthesis of(difluoromethylene)*** reaction proceeds through photocatalyzed[2+1]cyclization of readily available alkenes and diazo compound 1a followed by the work-up of the reaction through the elimination of silyl *** aromatic and aliphatic alkenes are tolerated by the mild reaction conditions,affording various(difluoromethylene)cyclopropanes in 44%–82%yield(>30 examples).Gram scale reaction and diversified downstream transformations highlight the synthetic potential of this *** experimental and DFT calculations suggest the involvement of triplet carbene intermediate.

关键词： triplet carbene cyclopropanation methylenecyclopropanes (difluoromethylene)cyclopropanes

Thermodynamics and kinetics of extracting zinc from zinc oxide ore by the ammonium sulfate roasting method

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 467-475页

作者： Yi Sun xiao-yi shen Yu-chun Zhai School of Materials and Metallurgy Northeastern University

Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by （NH4）2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the zinc oxide ore and （NH4）2SO4 in a temperature range of 573-723 K. The effects of reaction temperature and particle size on the extraction rate of zinc were also examined. It is found that a surface chemical reaction is the rate-controlling step in roasting kinetics. The calculated activation energy of this process is about 45.57 kJ/mol, and the kinetic model can be expressed as follows： 1 - （1 - α）1/3 = 30.85 exp（-45.57/RT）·t. An extraction ratio of zinc as high as 92% could be achieved under the optimum conditions.

关键词： zinc metallurgy extraction ammonium sulfate ore roasting thermodynamics kinetics

Technical assessment of synthetic natural gas (SNG) production from agriculture residuals

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Journal of Thermal Science 2013年第4期22卷 359-365页

作者： Guohui Song Fei Feng Jun xiao Laihong shen Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and Environment Southeast University Department of Mechanical Technology Nanjing College of Chemical Technology

This paper presents thermodynamic evaluations of the agriculture residual-to-SNG process by thermochemical conversion, which mainly consists of the interconnected fluidized beds, hot gas cleaning, fluidized bed methanation reactor and Selexol absorption unit. The process was modeled using Aspen Plus soft-ware. The process performances, i.e., CH4 content in SNG~ higher heating value and yield of SNGexergy efficiencies with and without heat recovery, unit power consumption, were evaluated firstly. The results indicate that when the other parameters remain unchanged, the steam-to-biomass ratio at carbon boundary point is the optimal value for the process. Im proving the preheating temperatures of air and gasifying agent is beneficial for the SNG yield and exergy effi ciencies. Due to the effects of COz removal efficiency, there are two optimization objectives for the SNG produc tion process：（I） to maximize CH4 content in SNC or （II） to maximize SNG yield. Further, the comparison among different feedstocks indicates that the decreasing order of SNG yield is： corn stalk 〉 wheat straw 〉 rice straw. The evaluation on the potential of agriculture-based SNG shows that the potential annual production of agriculture re sidual-based SNG could be between 555 108 - 611 108 m3 with utilization of 100% of the available unexplored resources. The agriculture residual-based SNG could play a significant role on solving the big shortfall of China＇s natural gas supply in future.

关键词： synthetic natural gas agriculture residual biomass gasification methanation fluidized bed exergy

Extraction of iron and aluminum from high-iron bauxite by ammonium sulfate roasting and water leaching

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Journal of Iron and Steel Research International 2019年第6期26卷 578-584页

作者： Ding Tian xiao-yi shen Yu-chun Zhai Penny xiao Paul Webley School of Metallurgy Northeastern University Shenyang 110819 Liaoning China School of Material Science and Engineering Dalian Jiaotong University Dalian 11602& Liaoning China Liaoning Key Laboratory for Metallurgical Sensor and Technology Northeastern University Shenyang 110819 Liaoning China School of Resources and Materials Northeastern University at Qinhuangdao Qinhuangdao 066004 Hebei China Department of Chemical & Biomolecular Engineering University of Melbourne Melbourne 3010 VIC Australia

High iron content is one of the challenges in utilizing the refractory bauxites in China. An improved method for treating the high-iron bauxite by roasting with (NH4)2SO4 was proposed, which offers a possible alternative method for utilizing the high-iron bauxite. The influences of the roasting time, roasting temperature, material ratio, and ore particle size on the extraction ratios of Fe and Al were studied, and the orthogonal test was used to optimize the reaction conditions. The optimized reaction conditions were proposed as follows: roasting temperature of 450 °C, roasting time of 120 min, material ratio of (NH4)2SO4 to ore of 2.5:1.0, and ore particle size below 80 jim. The roasting mechanism and kinetic parameters including the apparent activation energy and reaction rate constant were investigated. The results showed that the control step of the roasting process was the internal diffusion on the product layer and the apparent activation energy was 19.22 kJ mol-1 in the reaction temperature range. The kinetic equation was obtained finally.

关键词： High-iron bauxite Ammonium sulfate Roasting Reaction process Kinetics