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Photoinduced Electron Transfer Reaction between N,N-Dimethylaniline and 7,7-Dichloronorcarane

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Chinese Chemical Letters 1998年第6期9卷 509-512页

作者： Zhang, W Yang, L Wu, LM liu, yc liu, ZL Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China

U.V. irradiation of N,N-dimethylaniline (DMA) in the presence of 7,7-dichloronorcarane (DCN) in acetonitrile solution produces N-methyianiline, 4,4'-methylenebis-(N,N-dimethylaniline), N-(4'-N',N'-dimethylaminobenzyl)-N-methylaniline and 7-chloronorcarane as the major products. A photoinduced electron transfer mechanism is proposed.

关键词： photoinduced electron transfer dimethylaniline dichloronorcarane

Novel Photoinduced Electron Transfer Reaction of N-methylphenothiazine in Carbon Tetrachloride

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Chinese Chemical Letters 1998年第3期9卷 237-240页

作者： Guo, X Yang, L Wu, LM liu, yc liu, ZL Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Gansu Peoples R China

U.V. irradiation of N-methylphenothiazine 1 in carbon tetrachloride produced 3-(phenothiazin-N-yl-carbonyl)-N-methylphenothiazine 2 together with the radical cation salt 1(+) CCl4- and methyl chloride, presumably via ... 详细信息

关键词： methylphenothiazine photoinduced reaction carbon tetrachloride

Damping Behaviour and Mechanism of Graphite ParticulateReinforced Metal Matrix Composites

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Journal of Materials Science & Technology 1997年第6期13卷 447-451页

作者： liu, yc Yang, GC Lu, YL Zhu, ZG Northwestern Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China Acad Sinica Inst Solid State Phys Internal Frict & Defects Solids Lab Hefei 230031 Peoples R China

The effect of graphite particulate reinforcement on the resultant damping behaviour of ZA27 metal matrix composites (MMCs) has been investigated in an effort to develop a new functional material. The MMCs were processed by a spray atomization and deposition technique. The damping capacity, as well as the relative dynamic modulus, was measured at frequencies of 1 and 4 Hz in the 30 to 200 degrees C temperature range. There exists a transformation point at 55 degrees C in the internal friction and temperature spectrum of the MMCs. It is shown from microstructural analysis that the damping capacity of ZA27 can be significantly improved by the addition of graphites particulates through spray deposition processing. Finally, the operative damping mechanism is discussed in light of the data obtained from characterization of microstructure and damping capacity.

关键词： Graphite Damping Behaviour and Mechanism of Graphite ParticulateReinforced Metal Matrix Composites

Methylene green-mediated sensor highly sensitive to hydrogen peroxide based on entrapment of horseradish peroxidase in composite membrane of regenerated silk fibroin and poly(vinyl alcohol)

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Chinese Journal of Chemistry 1996年第4期14卷 359-366页

作者： Wu, YX liu, HY Qi, DY liu, yc Qian, JH liu, SH Yu, TY Deng, JQ SHANGHAI UNIV DEPT CHEM & CHEM ENGNSHANGHAI 200072PEOPLES R CHINA FUDAN UNIV DEPT MACROMOL SCI & CHEMSHANGHAI 200433PEOPLES R CHINA

A novel composite membrane of poly(vinyl alcohol) and regenerated silk fibroin was employed to immobilize horseradish peroxidase (HRP) and IR was used to give a useful insight into the structure of the composite membrane before and after ethanol treatment. A methylene green-mediated sensor sensitive to hydrogen peroxide was fabricated, based on the composite membrane as immobilization matrix for HRP. Cyclic voltammetry and amperometric measurement were for the first time utilized to demonstrate the suitability of methylene green as an electron transfer mediator between immobilized HRP and a glassy carbon electrode in bioelectrocatalytic reduction of hydrogen peroxide. Performance and characteristics of the sensor were evaluated in respect to response time, detection limit, applied potential and concentration of the mediator. The sensor possesses a variety of characteristics including good sensitivity, rapid response time and low detection of limit of 0.1 mu mol/L.

关键词： sensor poly(vinyl alcohol) regenerated silk fibroin methylene green horseradish peroxidase hydrogen peroxide

INFLUENCE OF EXTRUSION ON DAMPING CAPACITIES OF AS-SPRAY DEPOSITED HIGH SILICON ALLOY ZA27 MODIFIED BY CERIUM

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Acta Metallurgica Sinica(English Letters) 1997年第5期10卷 437-444页

作者： yc. liu G.C. Yang YL. Lu and Z.G. Zhu (State Key Lab. of Solidification Processing, Northwestern Polytechnic University, Xi’an 710072, China Laboratory of Internal Friction and Defects in Solids, Chinese Academy of Science, Hefei 230031, China ) Northwestern Polytechnical Univ Xi'an China

The effects of cerium modification and extrusion on the resultant damping behavior and mechanical properties of the as-sprayed high silicon alloy ZA27 were investigated in an thort to develop a new functional material possessing high damping capacity and good mechanical properties. The damping capacity, as well as the rslative dynamic modulus, was tneasured at frequencies of 1 and 4 Hertz over the 30 to 200℃runge. At below 80℃ the as-sprayed materials appear to be approximately Asquency independent. Above 80℃, the,naterials becotne temperature sensitive, exhibiting the highest damping for the lowest hequency. The extruded, as-sprayed high silicon alloy ZA27 modified by cerium has the highest damping capacity and elongation values among them. The micro8tructure of the as-sprayed high silicon alloy ZA27 modified by 0. 5 wt% cerium was made up of fine lamellar eutectoid, porositg, a light dot-like phase and a polygonal silicon-rich phase. Finally, the opemtive damping tnechanisms were discussed in light of the data obtained hem characterization of microstructure and damping capacity. The high damping capacity was attributed primarily to phase interface thermoelastic damping between the lamellar phases with various substrvctures,except for the grain refinement.

关键词： spray deposition damping capacity cerium modification extrusion

人热休克转录因子1功能反应与其半胱氨酸巯基氧化还原性能的相关性

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中华老年医学杂志 2003年第7期22卷 417-420页

作者：林正马中富黄帆徐康 liu Alice yc 中山大学附属第一医院中心实验室广州市510080 Department of CellBiology and Neuroscience

目的　评价半胱氨酸巯基氧化还原介导剂对人热休克转录因子 1(hHSF1)的氧化还原状态、结构和功能的作用 ,并试图去解释氧化作用在细胞衰老中对hHSF1转录反应的影响。　方法　通过改良的Westernblot方法检测不同氧化还原介导剂对hHSF1构... 详细信息

目的　评价半胱氨酸巯基氧化还原介导剂对人热休克转录因子 1(hHSF1)的氧化还原状态、结构和功能的作用 ,并试图去解释氧化作用在细胞衰老中对hHSF1转录反应的影响。　方法　通过改良的Westernblot方法检测不同氧化还原介导剂对hHSF1构象的影响 ;通过凝胶电泳迁移率变动试验检测hHSF1的DNA的结合活性。　结果　促进二硫键交联的氧化型介导剂二酰胺(DM )、一氧化氮 (NO+ )载体亚硝基谷胱甘肽 (GSNO)与含hHSF1的HeLa细胞S10 0提取液预培育 ,能在体外形成一个致密的、电泳中移动快速、分子内二硫键交联的氧化型hHSF1(ox hHSF1)单体构象 ;在电泳前加入还原型介导剂二硫苏糖醇 (DTT)能完全逆转。由于ox hHSF1形成 ,使hHSF1在体外不能被热诱导激活形成三体 ,失去和DNA结合的活性 ,而且这个作用仅对含半胱氨酸巯基的转录因子有特异性。　结论　hHSF1功能反应与其半胱氨酸巯基的氧化还原化学性能相关 ,氧化作用和hHSF1分子内二硫键交联有可能是衰老细胞热休克转录反应呈渐减性的原因。

关键词：人热休克转录因子1 半胱氨酸巯基氧化还原衰老细胞

晚期脊髓损伤患者胚胎嗅鞘细胞移植后的电生理评价

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中国组织工程研究与临床康复 2007年第24期11卷 4738-4741页

作者：陈琳黄红云王援朝张峰郗海涛张健刘彦铖北京市虹天济神经科学研究院

目的:采用客观的电生理检查手段评价胚胎嗅鞘细胞移植治疗晚期脊髓损伤的有效性。方法:①对象:选择2003-02/2005-01北京市西山医院暨北京康复中心神经外科收治的接受人胚胎嗅鞘细胞移植治疗的晚期完全性脊髓损伤患者199例,男164例,女35... 详细信息

目的:采用客观的电生理检查手段评价胚胎嗅鞘细胞移植治疗晚期脊髓损伤的有效性。方法:①对象:选择2003-02/2005-01北京市西山医院暨北京康复中心神经外科收治的接受人胚胎嗅鞘细胞移植治疗的晚期完全性脊髓损伤患者199例,男164例,女35例,平均年龄(34.7±11.3)岁,平均病程(4.7±5.5)年;受伤节段:颈段99例,胸段89例,胸腰段11例;受伤原因:车祸、摔伤、医源性损伤、机器挤压伤等。4个月流产胚胎由北京市虹天济神经科学研究院协作医院提供,产妇及其家属均签署知情同意书,实验经医院医学伦理委员会批准。②方法:取人胚胎嗅球,消化成单个嗅鞘细胞后培养2周。199例晚期完全性脊髓损伤患者均接受人胚胎嗅鞘细胞移植治疗,在全麻下行脊髓损伤节段后方入路,切开硬膜,显露出病变脊髓。分上下两点各注入50μL嗅鞘细胞悬液,细胞数共约1×106个。术后给予止血、抗感染等处理,未使用任何免疫抑制剂。③评估:移植前后分别采用肌电/诱发电位仪检查肌电图和椎旁躯体感觉诱发电位,每例患者检查2次,时间一致,且由同一医生操作。肌电图即检查患者大力收缩时的肌肉情况,以观察运动单位电位的数量、波幅及持续放电能力。椎旁躯体感觉诱发电位是于中线旁开2cm处两侧同时给予刺激,刺激强度以引起可见的肌肉抽动为准,在头皮上记录电位。方波刺激频率3Hz,强度20～40mA,时限0.2ms,观察感觉平面下降情况。结果:199例晚期完全性脊髓损伤患者均进入结果分析。①术后肌电图检查:93例(46.7%)显示部分受累肌肉大力收缩时募集波型改善,运动单位电位数量增加;105例(52.8%)无变化,1例(0.5%)比术前差。②椎旁躯体感觉诱发电位检查:90例(45.2%)显示感觉平面下降,其中左侧平均下降(1.9±1.2)个节段,右侧平均下降(2.0±1.2)个节段;107例(53.8%)无变化,2例(1.0%)双侧感觉平面上升。结论:对于胚胎嗅鞘细胞移植治疗晚期脊髓损伤患者,肌电图和椎旁躯体感觉诱发电位这两种电生理检查能较为客观的反映脊髓术后感觉和运动功能恢复情况。

关键词：脊髓损伤肌电图躯体感觉诱发电位嗅鞘细胞移植

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面向智能时代的人机合作心理模型

中国科学：信息科学 2018年第4期48卷 376-389页

作者：刘烨汪亚珉卞玉龙任磊禤宇明中国科学院心理研究所脑与认知科学国家重点实验室北京100101 中国科学院大学心理学系北京100049 首都师范大学心理学院北京100048 山东大学计算机科学与技术学院济南250101 北京航空航天大学自动化科学与电气工程学院北京100191 北京航空航天大学精准医疗高精尖创新中心北京100191

最近10年,人工智能和人机交互研究突飞猛进,在学术界和产业界都掀起了热潮.不管是突破人工智能的瓶颈,还是实现和谐、自然的人机交互,都迫切需要符合人类认知机理和心理规律的人机交互心理模型.建构面向智能时代的人机合作心理模型,不... 详细信息

最近10年,人工智能和人机交互研究突飞猛进,在学术界和产业界都掀起了热潮.不管是突破人工智能的瓶颈,还是实现和谐、自然的人机交互,都迫切需要符合人类认知机理和心理规律的人机交互心理模型.建构面向智能时代的人机合作心理模型,不但可以解释、模拟和预测人类的行为,而且可以指导相应的智能系统和人机交互设计.本文回顾和总结了以往的人机交互模型和认知计算模型,基于最近10年的实验证据和研究发现,试图拓展和深化已有的认知模型,建构面向智能时代的人机合作心理模型,为智能时代的人机交互研究提供理论基础.

关键词：人工智能人机合作人机交互心理模型感知认知动作

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang Changyu liu Yangyang liu Hui Wang Xiaojie liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode