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Photocatalytic decarboxylative alkylations of C(sp^(3))–H and C(sp^(2))–H bonds enabled by ammonium iodide in amide solvent

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Science China Chemistry 2021年第3期64卷 439-444页

作者： Guang-Zu wang ming-Chen Fu Bin zhao Rui Shang Department of Chemistry University of Science and Technology of ChinaHefei 230026China Department of Chemistry School of ScienceThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-0033Japan

A simple ammonium iodide salt in amide solvent catalyzes regioselective decarboxylative alkylation of C(sp^(3))-H bonds of Naryl glycine derivatives, of C(sp^(2))-H bond of heteroarenes, and cascade radical addition to unsaturated bond followed by intramolecular addition to arene, with a broad scope of N-hydroxyphthalimide derived redox active esters under visible light irradiation. The reactions are suggested to proceed through photoactivation of a transiently assembled chromophore from electron-deficient phthalimide moiety and iodide anion through an anion-π interaction in solvent cage followed by diffusion to generate solvated free radical species to react with C-H substrates. The simplicity, practicality, and broad substrate scope of this method highlight the synthetic power of photocatalysis through transiently assembled chromophore, and will hopefully inspire further developments of low cost photocatalysis based on various non-covalent interactions, which are prevalent in supramolecular chemistry and biosystems, for sustainable organic synthesis.

关键词： decarboxylative alkylation transiently assembled chromophore anion-πinteraction ammonium iodide solvent cage

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霉酚酸酯治疗甲状腺相关性眼病临床对照研究

医学研究生学报 2003年第12期16卷 911-913页

作者：王坚王扬天邵加庆赵明王晓杜宏南京军区南京总医院内分泌科江苏南京210002

目的 :对比霉酚酸酯等几种不同免疫抑制药对甲状腺相关性眼病 (TAO)或称Graves眼病 (Graves′ ,Ophthal mopathy ,GO)的疗效 ,旨在寻求免疫治疗的有效手段。　方法 :将TAO 5 4例 ,分成A、B两大组 ,A组随机采用泼尼松 (1 6例 ,完成治疗... 详细信息

目的 :对比霉酚酸酯等几种不同免疫抑制药对甲状腺相关性眼病 (TAO)或称Graves眼病 (Graves′ ,Ophthal mopathy ,GO)的疗效 ,旨在寻求免疫治疗的有效手段。　方法 :将TAO 5 4例 ,分成A、B两大组 ,A组随机采用泼尼松 (1 6例 ,完成治疗者 1 3例 )或雷公藤总甙 (TⅡ ,1 5例 )治疗 ;B组随机采用霉酚酸酯 (MMF ,1 2例 )或环孢素 (CsA ,1 1例 )治疗 ,疗程 1 2周。疗效判断采用改良Given Wilson积分指数系统 ,设定积分下降或上升≥ 3分为好转或恶化 ,0 .0 5 )。各组治疗后眼病分值均有一定程度下降 (P 5 % ,2例血糖增高 ,停药后血糖恢复 ,该组共 3例退出治疗 ,其他各组无因药物不良反应而中途退出者。MMF组未发现有明确的药物不良反应。　结论 :新型免疫抑制药MMF用于治疗Graves眼病疗效优于CsA 。

关键词：甲状腺相关性眼病免疫治疗霉酚酸酯

SELECTIVE SEPARATION AND RECOVERY PROCESS—Supercritical fluid extraction and fractionation

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石油学报（石油加工） 2001年第1期17卷 47-55页

作者： zhao Suo-qi XU Chun-ming wang Ren-an University of Petroleum

A selective separation and recovery process has been developed based on the supercritical fluid extraction and fractionation (SFEF) technology. The solvent used varies from C3 to C5, depending on process objective. Basic research work has been done on the phase behavior, phase equilibria and modeling of a number of systems including petroleum residue, polymers, waxes and lubricants with the light hydrocarbon solvents. Semi-batch pilot and continuous pilot experiments were performed to establish data base for the process design of industrial scale. The effects of operation para-meters, such as temperature, pressure, ratio of solvent to oil and residence time, on separation selectivity and yield of extracts were studied in a wide range. Industrial demonstration plant with a capacity of 15 kt/a was setup and has run for a sufficient long period of time to confirm the design and to obtain the energy cost and economic analysis data for further commercial scale up. It was found that the process offers high efficient products and solvent recovery.

关键词： SFEF 残油超临界流体萃取分馏法分离工艺

不同荷载作用下五边形石墨烯的变形破坏机理研究

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原子与分子物理学报 2025年第6期42卷 51-57页

作者：赵泽若韩同伟李仁葛峻铭王嘉越江苏大学土木工程与力学学院镇江212013

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯... 详细信息

五边形石墨烯是一种完全由碳五元环组成的准二维的亚稳态碳结构,在不同载荷作用下其变形破坏机理仍需进一步研究.本文基于ReaxFF反应力场采用分子动力学方法模拟研究了五边形石墨烯的拉伸、剪切和纳米压痕破坏过程,得到了五边形石墨烯的拉伸和剪切应力-应变曲线以及压入载荷-位移曲线,系统分析了五边形石墨烯的变形破坏机理,并验证了五边形石墨烯在不同载荷作用下是否表现出塑性变形特征的一致性问题.研究结果表明,通过拉伸或纳米压入等不同加载方式均可准确测出五边形石墨烯的本征力学性能参数,其杨氏模量265.4~285.1 N/m,与第一性原理计算结果一致.研究还发现,五边形石墨烯在拉伸、剪切和纳米压痕过程中均会出现不可逆的塑性变形特征,而引起塑性变形的原因是由于不可逆的碳五元环向碳多元环结构的转变.以上研究结果可为基于五边形石墨烯的微/纳米机电系统的实际应用提供重要指导.

关键词：五边形石墨烯变形破坏机理分子动力学

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Effects of soil drought stress on photosynthetic gas exchange traits and chlorophyll fluorescence in Forsythia suspensa

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Journal of Forestry Research 2018年第1期29卷 45-53页

作者： Ying Lang ming wang Jiangbao Xia Qiankun zhao Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection/College of Agriculture and Forestry Science Linyi UniversityLinyi 276000 People's Republic of China State Key Laboratory of Earth Surface Processes and Resource Ecology/Academy of Disaster Reduction and Emergency Management Beijing Normal UniversityBeijing 100875 People's Republic of China Shandong Provincial Key Laboratory of Eco-Environmental Science for Yellow River Delta Binzbou UniversityBinzhou 256603 People's Republic of China Linyi Agricultural Comprehensive Development Office Linyi 276000 People's Republic of China

To clarify the changes in plant photosynthesis and mechanisms underlying those responses to gradually increasing soil drought stress and reveal quantitative relationships between photosynthesis and soil moisture,soil water conditions were controlled in greenhouse pot experiments using 2-year-old seedlings of Forsythia suspensa（Thunb.） Vahl. Photosynthetic gas exchange and chlorophyll fluorescence variables were measured and analyzed under 13 gradients of soil water content. Net photosynthetic rate（PN）, stomatal conductance（gs）, and water-use efficiency（WUE） in the seedlings exhibited a clear threshold response to the relative soil water content（RSWC）. The highest PNand WUEoccurred at RSWCof51.84 and 64.10%, respectively. Both PNand WUEwere higher than the average levels at 39.79% B RSWCB 73.04%. When RSWCdecreased from 51.84 to 37.52%,PN, gs, and the intercellular CO2 concentration（Ci）markedly decreased with increasing drought stress; the corresponding stomatal limitation（Ls） substantially increased, and nonphotochemical quenching（NPQ） also tended to increase, indicating that within this range of soil water content, excessive excitation energy was dispersed from photosystem II（PSII） in the form of heat, and the reduction in PNwas primarily due to stomatal *** RSWCdecreased below 37.52%, there were significant decreases in the maximal quantum yield of PSII photochemistry（Fv/Fm） and the effective quantum yield of PSII photochemistry（UPSII）, photochemical quenching（qP）, and NPQ; in contrast, minimal fluorescence yield of the dark-adapted state（F0） increased markedly. Thus,the major limiting factor for the PNreduction changed to a nonstomatal limitation due to PSII damage. Therefore, an RSWCof 37.52% is the maximum allowable water deficit for the normal growth of seedlings of F. suspensa, and a water content lower than this level should be avoided in field soil water management. Water contents should be maintained in the range of 39.79% B RSWCB 73.04% to en

关键词： Chlorophyll fluorescence Gas exchange Photosynthetic rate Soil water deficit Stomatal mechanism Water-use efficiency

Active Disturbance Rejection Position Servo Control of PMSLM Based on Reduced-order Extended State Observer

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Chinese Journal of Electrical Engineering 2020年第2期6卷 30-41页

作者： ming Li Jiwen zhao Yuepeng Hu Zhen wang School of Electrical Engineering and Automation Anhui UniversityHefei 230601China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

To enhance the control accuracy of permanent magnet synchronous linear motor(PMSLM)servo systems affected by disturbances,such as time-varying parameters and abrupt load changes,an active disturbance rejection control(ADRC)algorithm based on a reduced-order extended state observer(ESO)is adopted to suppress the disturbances on the control ***,the system’s ability to estimate disturbances is enhanced by linearizing the ***,the pole placement method is used for the construction of a reduced-order ESO that can reduce the influence of the number of adjustment parameters and the phase *** parameters of the reduced-order ADRC are adjusted,the optimal control parameters are selected,and the stability of controller is ***,practical experiments prove that the proposed method can improve control accuracy under multiple working conditions and features strong anti-interference *** is a smaller steady-state error,and no overshoot is observed.

关键词： PMSLM ADRC reduced-order ESO anti-interface

Partial Iterative Decode of Turbo Codes for On-Board Processing Satellite Platform

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China Communications 2015年第11期12卷 104-111页

作者： LI Hang GAO Zhen zhao ming wang Jing Department of Electronic Engineering Tsinghua University School of Electronic Information Engineering Tianjin University

There is a contradiction between high processing complexity and limited processing resources when turbo codes are used on the on-board processing(OBP)satellite *** solve this problem,this paper proposes a partial iterative decode method for on-board application,in which satellite only carries out limited number of iteration according to the on-board processing resource limitation and the throughput capacity *** this method,the soft information of parity bits,which is not obtained individually in conventional turbo decoder,is encoded and forwarded along with those of information *** save downlink transmit power,the soft information is limited and normalized before *** iteration number and limiter parameters are optimized with the help of EXIT chart and numerical analysis,*** results show that the proposed method can effectively decrease the complexity of onboard processing while achieve most of the decoding gain..

关键词： satellite communication on-board processing partial iterative decoding

COPD合并肺心病患者血清hs-CRP、BNP的含量及临床意义

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中国实验诊断学 2016年第10期20卷 1670-1672页

作者：赵明丽王玉忠张露露南京市江宁医院老年医学科江苏南京211100

目的探讨COPD合并肺心病患者血清hs-CRP、BNP的含量变化及临床意义。方法分别选取2013年4月至2014年3月在我院门诊及住院治疗的56名COPD合并肺心病的患者、62名单纯患有COPD的患者及同期在我院进行健康体检者76名作为研究对象,检测三组... 详细信息

目的探讨COPD合并肺心病患者血清hs-CRP、BNP的含量变化及临床意义。方法分别选取2013年4月至2014年3月在我院门诊及住院治疗的56名COPD合并肺心病的患者、62名单纯患有COPD的患者及同期在我院进行健康体检者76名作为研究对象,检测三组人的血清hs-CRP和BNP的含量,并对它们进行分析。结果 COPD合并肺心病患者及COPD患者的血清hs-CRP和BNP高于对照组,COPD合并肺心病患者的血清hs-CRP和BNP高于COPD患者,COPD合并肺心病的患者心功能分级越高的患者血清hs-CRP和BNP含量越高,PaO2越低。COPD合并肺心病患者的血清hs-CRP和BNP的含量与心功能分级呈正相关关系,以上差异均有统计学意义。结论血清hs-CRP和BNP含量变化与COPD合并肺心病的程度有关。

关键词： COPD合并肺心病血清 hs-CRP BNP

Forest-height inversion using repeat-pass spaceborne polInSAR data

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Science China Earth Sciences 2014年第6期57卷 1314-1324页

作者： LI Zhen GUO ming wang ZhongQiong zhao LiFang Key Laboratory of Digital Earth Sciences Institute of Remote Sensing and Digital EarthChinese Academy of Sciences College of Resoures and Environment University of the Chinese Academy of Sciences Beijing Research Institute of Uranium Geology

Forest-height inversion using airborne double-antenna synthetic aperture radar(SAR)systems has been widely researched,leading to increasing *** SAR Interferometry(PolInSAR)data from spaceborne single-antenna SAR systems,which are influenced by temporal decorrelation,have difficulty inverting forest *** the temporal decorrelation effect,the classical random volume over ground(RVoG)model has been proven to invert forest height with significant errors,using repeat-pass PolInSAR *** consideration of this problem,the temporal decorrelation RVoG(TD-RVoG;based on the RVoG)model was *** this study,an improved TD-RVoG model is presented,with a new temporal decorrelation *** with TD-RVoG,the new model has fewer unknown parameters and can be applied in a three-stage inversion *** of the new model is demonstrated by Advanced Land Observing Satellite/Phased Array type L-band SAR(ALOS/PALSAR)*** show that the improved TD-RVoG has better accuracy,with inversion error less than 1.5m.

关键词： repeat-pass PolInSAR forest-height inversion temporal decorrelation model improved TD-RVoG model