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机电产品开发与创新 2023年第4期36卷 43-48页

作者：罗继曼肖雅心马思源宋益德吴昊沈阳建筑大学机械工程学院辽宁沈阳110168

再生运动链连杆机构传动效率高,承载能力强,自由度少,容易实现预期的运动轨迹,基于该构型方法设计了一种多连杆的机器人单腿机构。为了获得更好的运动规律和动力学特性,研究了机器人运动学和动力学问题。首先,基于几何法和拉格朗日法分... 详细信息

再生运动链连杆机构传动效率高,承载能力强,自由度少,容易实现预期的运动轨迹,基于该构型方法设计了一种多连杆的机器人单腿机构。为了获得更好的运动规律和动力学特性,研究了机器人运动学和动力学问题。首先,基于几何法和拉格朗日法分别进行了运动学和动力学的理论建模。然后,通过运动分析软件Adams进行了运动学和动力学仿真。仿真中发现了机构运动不均匀现象,通过连杆尺度调整,消除了机构的急回特性,使速度和加速度波动分别降低了约10.18%和9.8%。最后,基于matlab的理论建模与分析软件Adams仿真进行了相互验证。由此,确定了具有运动平稳,所受冲击小和承载大特点的该机器人单腿机构方案是可行的。

关键词：再生运动链四足机器人运动学和动力学

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Two-dimensional numerical and eco-toxicological modeling of chemical spills

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Frontiers of Environmental Science & Engineering 2009年第2期3卷 178-185页

作者： Suiliang HUANG yafei JIA Sam S.y.WANG Numerical Simulation Group for Water Environment Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of EducationTianjin Key Laboratory of Environmental Remediation and Pollution ControlCollege of Environmental Science and EngineeringNankai UniversityTianjin 300071China National Center for Computational Hydroscience and Engineering The University of MississippiOxfordMS 38677USA

The effects of chemical spills on aquatic nontarget organisms were evaluated in this *** on a review of three types of current eco-toxicological models of chemicals,i.e.,ACQUATOX model of the US-EPA,Hudson River Model of PCBs,and critical body residual(CBR)model and dynamic energy budget(DEBtox)model,this paper presents an uncoupled numerical ecotoxicological *** transport and transformation of spilled chemicals were simulated by a chemical transport model(including flow and sediment transport),and the mortalities of an organism caused by the chemicals were simulated by the extended threshold damage model,*** to extreme scarcity of data,this model was applied to two hypothetical cases of chemical spills happening upstream of a *** analysis and simulated results indicated that this model is capable of reasonably predicting the acute effects of chemical spills on aquatic ecosystems or organism killings.

关键词： chemical spills acute effects aquatic ecosystem eco-toxicological modeling

具有同分异构体的磺化聚酰亚胺质子交换膜对全钒液流电池性能影响

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高分子材料科学与工程 2023年第8期39卷 134-141页

作者：刘鑫马磊杨洁刘蕾王超中北大学材料科学与工程学院山西太原030051

由于具有同分异构结构的聚合物在性能方面具有明显的差异,文中以1,4,5,8-萘四甲酸酐(NTDA)为二酐单体,3,3’-二氨基二苯砜和4,4’-二氨基二苯砜提供同分异构结构单元,4,4'-二氨基-2,2'-二磺酸基-联苯水合物(BDSA)为磺化二胺单体,制备了... 详细信息

由于具有同分异构结构的聚合物在性能方面具有明显的差异,文中以1,4,5,8-萘四甲酸酐(NTDA)为二酐单体,3,3’-二氨基二苯砜和4,4’-二氨基二苯砜提供同分异构结构单元,4,4'-二氨基-2,2'-二磺酸基-联苯水合物(BDSA)为磺化二胺单体,制备了2种具有不同空间构型的磺化聚酰亚胺(SPI),并将其作为质子交换膜(PEM)使用在全钒液流电池(VRFB)中。3,3’-二氨基二苯砜的螺旋结构可有效增强3-SPI化学结构的柔性,有助于分子链的缠结,使其具有优异的力学性能、尺寸稳定性和阻钒能力(8.08×10^(-8)cm^(2)/min)。4-SPI构型的离子电导率(47.21 mS/cm)与Nafion 212膜(49.37 mS/cm)相似,但离子选择性(4.25×10^(5)S·min/cm^(3))约是Nafion 212(1.08×10^(5)S·min/cm^(3))的4倍。在单电池测试中,4-SPI仍表现出良好的综合性能,在160 ma/cm^(2)电流密度下,能量效率(ee)达到77%。同时,4-SPI也表现出良好的稳定性,其ee在30次循环之后仍保持在84%以上。

关键词：磺化聚酰亚胺全钒液流电池质子交换膜同分异构体

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聪明泉（小学1-3年级） 2019年第3期 30-31页

作者： ee(图) 不详

Asymmetric Intramolecular Hydroalkoxylation of Unactivated Alkenes Catalyzed by Chiral N-Triflyl Phosphoramide and TiCl4

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Chinese Journal of Chemistry 2020年第6期38卷 565-569页

作者： Pengyuan Zhao Aolin Cheng Xinxu Wang Jiguo ma Guoqing Zhao yingkun Li yi Zhang Baoguo Zhao The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional materials Shanghai Normal UniversityShanghai 200234China

By using a combination of a chiral/V-triflyl phosphoramide and TiCl4 as the catalyst,a new process for asymmetric intramolecular hydroalkoxylation of unactivated alkenes was developed,producing various chiral tetrahyd... 详细信息

关键词： chiral Chiral intramolecular

Progress of Optical Fiber Sensors and Its Application in Harsh Environment

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Photonic Sensors 2011年第1期1卷 84-89页

作者： Min ZHANG Xiaohong ma Liwei WANG Shurong LAI Hongpu ZHOU Huafeng ZHAO yanbiao LIAO Optical Fiber Sensors Lab EE Dept.Tsinghua University100084 BeijingChina

Fiber sensors have been developed for industry application with significant *** this paper,Fiber sensors for oil field service and harsh environment monitoring which have been investigated in Tsinghua University are *** discussing the requirements of practical applications,the key technologies of long-period fiber grating(LPFG)based fiber sensor,optical spectrum analyzer for oil detection,laser induced breakdown spectroscopy(LIBS)system for soil contamination monitoring,and seismic sensor arrays are described.

关键词： Fiber sensor seismic geophone gas sensor spectrum analyzer LIBS

Redox deracemization of α-substituted 1,3-dihydroisobenzofurans

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Chinese Chemical Letters 2021年第7期32卷 2305-2308页

作者： Xiaohan Chen Ran Zhao Ziqiang Liu Shutao Sun yingang ma Qingyun Liu Xia Sun Lei Liu School of Pharmaceutical Sciences Cheeloo College of MedicineShandong UniversityJi'nan 250012China College of Chemical and Biological Engineering State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and TechnologyShandong University of Science and TechnologyQingdao 266590China School of Chemistry and Chemical Engineering Shandong UniversityJi'nan 250100China Shenzhen Research Institute of Shandong University Shenzhen 518057China Department of Pharmacology School of Basic Medical SciencesCheeloo College of MedicineShandong UniversityJi'nan 250012China

Chiralα-substituted 1,3-dihydroisobenzofurans are key scaffolds in a number of bioactive natural products and synthetic ***,catalytic asymmetric approaches have been rarely ***,a redox deracemization technology is adopted to address the catalytic asymmetric synthesis.A broad range ofα-aryl substituted 1,3-dihydroisobenzofurans are effectively deracemized in high efficiency with excellent ee.α-Alkynyl substituted ethers were also compatible with the deracemization technology.

关键词： 1,3-Dihydroisobenzofuran Asymmetric catalysis Redox deracemization Oxocarbenium ion Synthetic method

Asymmetric Michael addition reactions catalyzed by a novel upper-rim functionalized calix[4]squaramide organocatalyst

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Chinese Chemical Letters 2020年第12期31卷 3259-3262页

作者： Ke yang Zhiyan ma Hong-Xiao Tong Xiao-Qiang Sun Xiao-yu Hu Zheng-yi Li Jingsu Key Laboratory of Advanced Catalytic materials&Technology School of Petrochemical EnginerngChangzhou LniversityChangzhou 213184China College of material Science and Technology Nanjing University of Aeronatutics and AstronauricsNanjing 211100China

A novel upper-rim functionalized calix[4]squaramide organocatalyst bearing bis-squaramide and cyclohexanediamine scaffolds was designed and prepared to catalyse a serial of asymmetric Michael addition of 1,3-dicarbo nyl compounds to a,β-unsaturated carbonyl compounds in high yields(up to 99%)and good to excellent enantiomeric excesses(up to 99%ee).The comparative experiments indicated that the cooperative effect between calixarenes cavitives and chiral catalytic centers on this calix[4]squaramide catalyst could promote these ***,this strategy also provides valuable and easy access to chiral chromene,naphthoquinone and acetylacetone derivatives,which are important skeletons in biological and pharmaceutical compounds.

关键词： Calixsquaramide Supramolecular catalyst Asymmetric catalysis Michael addition Organic synthesis

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隔热胶体装药结构的耐热防护与爆炸性能

含能材料 2023年第3期31卷 306-315页

作者：王飞马宏昊沈兆武安徽理工大学、深部煤矿采动响应与灾害防控国家重点实验室安徽淮南232001 中国科学技术大学、中国科学院材料力学行为和设计重点试验室安徽合肥230027

为了研究高温环境下胶体装药结构的安全防护问题及其爆炸特性变化,设计了由隔热外层、吸热胶体、乳化炸药组成的装药结构,采用物性测定、测温分析、爆炸测试技术(水下爆炸,爆速实验,胶体介质近场爆压测量)及现场实验(殉爆实验,炮孔传爆)... 详细信息

为了研究高温环境下胶体装药结构的安全防护问题及其爆炸特性变化,设计了由隔热外层、吸热胶体、乳化炸药组成的装药结构,采用物性测定、测温分析、爆炸测试技术(水下爆炸,爆速实验,胶体介质近场爆压测量)及现场实验(殉爆实验,炮孔传爆),分别研究了装药结构中3种胶体配比(高分子吸水树脂(SAP)质量比分别为0,0.5%和1%)与乳化炸药2种敏化方式(亚硝酸钠敏化、膨胀珍珠岩敏化)对隔热特性和爆炸性能的影响。结果表明:含0.5%SAP的胶体材料适用于装药结构,具有阻燃性、高比热容、低导热系数特性,隔热防护时间延长至55 min。水下爆炸与爆速实验中,随着水浴加热(100℃)时间的增加,2种敏化方式药包的各项爆轰参数(冲击波压力峰值、比冲量、爆速、爆炸总能量)均持续降低。受到乳化炸药破乳与敏化热点减少的双重影响,亚硝酸钠敏化型药包(ee-SN)的爆轰性能衰减比例高于膨胀珍珠岩敏化型药包(ee-EP)。加热2 h后,膨胀珍珠岩、亚硝酸钠敏化的药包爆炸总能量损失分别为4.76%,17.62%。在胶体介质近场爆压测量中,装药结构中胶体层会减弱爆炸冲击波强度。但现场实验爆破效果良好,且实现了装药结构30 mm殉爆、炮孔内稳定传爆,说明该胶体装药结构具有很好的高温爆破应用前景。

关键词：高温爆破胶体材料隔热装药结构乳化炸药热安全性冲击波衰减