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Chemical Research in Chinese Universities 1992年第3期8卷 224-230页

作者： DING wei-yu , cao wei-guo, ZHU Dian-kui and TONG wei-qi (Department of Chemistry, Shanghai University of Science and Technology, Shanghai, 201800)

The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl 2-perfluoroalkynoates 2a-c in the presence of K2CO3 at room temperature gives two adducts, (E)-methyl 3-per-fluoroalkyl-4-( 3-carboethoxy-2-furanyl )-2-triphenylphosphoranylidene-3-butenoates 3a-c and (E)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-4-triphenylphos-phoranylidene-2-butenoates 4a-c. (Z)-Methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c can be synthesized stereoselectively with high yields when an aqueous DMF solution of 3c, 4c or a mixture of 3a-b and 4a-b was heated at 140℃ for 8 h.

关键词： (Z)-3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoate Phospho-rane Methyl 2-perfluoroalkynoate Hydrolysis Stereoselective synthesis

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen CHEN wei cao Bingwei LIU Xinhui LI Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (CHP) gasification porous media combustion power generation

Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期34卷 223-241页

作者： wei Xinyi ZHANG Nan ZHANG Zhaoli cao Xiaoling YUAN Yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

关键词： copper metal foam heat transfer enhancement phase change materials regionalized enhancement

Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang Juan Li wei-Hong Zhu Zhiqian guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： guo Xingduo LI Yinran LI Rennian MA Yulong wei Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems Gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine turbulence wind tunnel experiment wind turbine wake

A new criterion for predicting glass forming ability of bulk metallic glasses and some critical discussions

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Progress in Natural Science:Materials International 2011年第2期21卷 164-172页

作者： Bang-shao DONG,Shao-xiong ZHOU.De-ren LI,cao-wei LU,Feng guo,Xiao-jun NI,Zhi-chao LU Advanced Technology & Materials Co.,Ltd.,Central Iron & Steel Research Institute,Beijing 100081,China Advanced Technology & Materials Co. Ltd. Central Iron & Steel Research Institute Beijing 100081 China

A modified criterion,β’,defined as Tg/Tx-Tg/(Tl·η))(Tg,Tx,Tlandηdenote the glass transition temperature,the onset of crystallization temperature,the liquidus temperature and constant coefficient,respectively),has been proposed for assessing the glass-forming ability(GFA) of bulk metallic glasses(BMGs).A survey of the readily available experimental data associated with the thermal analysis of various BMG alloys demonstrates that the newβ’ criterion exhibits much better correlation with the GFA than other currently used ***,it is more significant from statistical results to note that,all criteria including the currently proposed criterionβ’,which are all combined by Tg,Txand Tl,almost have equal ability in measuring the glass forming ability in any glass-forming system.

关键词： amorphous materials metallic glasses glass-forming ability thermal analysis criterion

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激光干扰扩束系统光机结构设计

光子学报 2014年第6期43卷 162-168页

作者：何秉高安志勇曹秒曹维国长春理工大学长春130022 长春大学长春130022

针对常规红外干扰技术存在的能量无法集中、隐蔽性差且无法进行变倍切换等实际问题,提出一种离轴双反射式激光干扰扩束系统的设计方案,并对离轴双反射镜组,转向平面反射镜及支撑固定机构等主要组成部分进行了光机结构设计.为实现扩束比... 详细信息

针对常规红外干扰技术存在的能量无法集中、隐蔽性差且无法进行变倍切换等实际问题,提出一种离轴双反射式激光干扰扩束系统的设计方案,并对离轴双反射镜组,转向平面反射镜及支撑固定机构等主要组成部分进行了光机结构设计.为实现扩束比的变倍切换功能,采用新型离轴副镜组件设计;为减小镜面变形,离轴主副镜组均采用微应力设计.分析结果表明,在-20^+60℃温度范围内,主副镜组轴向最大位移小于等于0.01mm,主副镜组的反射镜面形误差小于等于71.9nm;系统一阶固有频率108.3Hz,其支撑结构应力响应远小于材料的屈服极限.实际测试发现,系统可实现1:10.02(19.92,25.02)扩束比,满足设计技术指标要求.分析及试验结果表明,系统光机结构设计合理,完全满足实际应用要求.

关键词：光学设计变倍扩束离轴反射光机结构激光干扰分析测试

Spectral Distance Distributions for Non-rigid Objects

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Computer Aided Drafting,Design and Manufacturing 2013年第2期23卷 17-24页

作者： cao wei-guo Li Hai-yang LI Shi-rui LIU Yu-jie LI Hua Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China School of Computer Science and Communication Engineering China University of Petroleum Qingdao 266555 China.

Non-rigid shape deformation without tearing or stretching is called isometry. There are many difficulties to research non-rigid shape in Euclidean space. Therefore, non-rigid shapes are firstly embedded into a none-Euclidean space. Spectral space is chosen in this paper. Then three descriptors are proposed based on three spectral distances. The existence of zero-eigenvalue has negative effects on computation of spectral distance, Therefore the spectral distance should be computed from the first non-zcro-eigenvalue. Experiments show that spectral distance distributions are very effective to describe the non-rigid shapes.

关键词： non-rigid shape analysis pattern recognization isometry Laplace-Beltrami operator spectrum

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基于PC104的DCS冗余软件设计与实现

化工自动化及仪表 2005年第3期32卷 42-46页

作者：薛福珍曹卫国中国科学技术大学自动化系安徽合肥230027

介绍DCS中冗余组态软件和冗余运行软件的设计与实现,包括冗余系统硬件结构、冗余系统软件结构、冗余参数组态、组态信息的存储、组态信息的下传通信、冗余运行软件切换控制逻辑、错误表管理、冗余运行软件与I/O模块的数据交换。这一软... 详细信息

介绍DCS中冗余组态软件和冗余运行软件的设计与实现,包括冗余系统硬件结构、冗余系统软件结构、冗余参数组态、组态信息的存储、组态信息的下传通信、冗余运行软件切换控制逻辑、错误表管理、冗余运行软件与I/O模块的数据交换。这一软件实现能有效提高DCS在工业应用中的可靠性和安全性。

关键词：组态存储切换控制逻辑错误表

无溶剂研磨条件下四氢苯并吡喃衍生物的一锅法合成

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有机化学 2007年第8期27卷 1018-1021页

作者：张慧曹卫国任仲皎上海大学化学系上海200444

四氢苯并吡喃衍生物在药物和农药研究中有着广泛的用途.基于合成这类化合物的传统方法所用溶剂多为对环境不利的极性溶剂,且合成需分步进行,在提倡绿色化学和发展节约型经济的今天,如何改良这类反应已成为一个热点.本工作通过选择不同... 详细信息

四氢苯并吡喃衍生物在药物和农药研究中有着广泛的用途.基于合成这类化合物的传统方法所用溶剂多为对环境不利的极性溶剂,且合成需分步进行,在提倡绿色化学和发展节约型经济的今天,如何改良这类反应已成为一个热点.本工作通过选择不同的碱尝试反应最佳条件,发现用价廉易得的碳酸钾为碱,对不同官能团取代的底物芳醛采用研磨的手段,在无溶剂条件下,一锅法可成功合成四氢苯并吡喃衍生物.该法条件温和,收率高,易于操作,对环境影响小.

关键词：四氢苯并吡喃一锅法研磨无溶剂