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Asymmetric Cyclopropanation Catalyzed by a Copper-(Schiff-base) Complex with Double Chiral Centers

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Chemical Research in Chinese Universities 2003年第2期19卷 238-239页

作者： jiang chang sheng LI You gui jiang Chen WEN Ji wu YOU Tian pa Department of Chemistry Universtity of Science&Technology of ChinaHefei 230026 P.R.China

The catalytic asymmetric Cyclopropanation of olefins with diazoacetate estershas been one of the most important methodologies for the formation of chiral cyclopropanecompounds. The design and the synthesis of an efficient catalyst are a challenging task for organicchemists. The catalysts containing various metals and optically active ligands have been employedfor the reaction. The copper-(Schiff-base) complex was reported by Nazoki et al., which exploitedthe area of catalytic asymmetric reaction though the degree of enantios-election was low. Nearly 10years later extensive systematic screening of salicylaldimine ligands by Aratani and his coworkersbrought about design changes in the copper-(Schiff-base) complex that gave dramatic improvements onoptical yields for the selected intermolecular Cyclopropanation reactions.

关键词： Asymmetric cyclopropanation Catalysis Copper-(Schiff-base)

Research on Disturbance in NearspaceVehicle Longitudinal Trajectory System

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Research on Disturbance in NearspaceVehicle Longitudinal Tra...

Online-SVR-compensated nonlinear generalized predictive control for hypersonic vehicles

第25届中国控制与决策会议

作者： HE Nai-bao GAO Qian GONG Cheng-long jiang chang-sheng School of Electrical Engineering Huaihai Institute of Techology College of Automatic Engineering Nanjing University of Aeronautics and Astronautics

ISBN: (纸本)9781467355339

Considering the severe changes of aero-dynamic parameters and susceptibility on the external disturbances of nearspace vehicle （NSV）, a backstepping control strategy with robust adaptive dynamic surface is proposed in this paper for the disturbance problem in the NSV longitudinal trajectory system during the hypersonic process. Firstly, the complex nonlinear longitudinal dynamic model is transformed into nonlinear affine model by using the input-output feedback linearization method. Meanwhile, the "computer explosion" in the computation procedures for derivatives is avoided with the estimation of the virtual control law in one-order low pass filter. Then,the robustness item in the virtual controller ,which combined with approximation capability of neural network, is used to eliminate the parameter uncertainties and external disturbances in NSV. The simulation results show the improved robustness in this method with reduced complexity.

关键词： dynamic surface control Robust Control Nearspace Vehicle neural network

来源： cnki会议评论

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Science China(Information Sciences) 2011年第3期54卷 551-562页

作者： CHENG Lu , jiang chang sheng & PU Ming College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China 1. College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

This paper is concerned with the problem of hypersonic vehicle (HSV) attitude control system in uncertain flight conditions. The problem can be expressed as the adaptive robust control for a class of uncertain nonlinear systems. Based on the description of the aerodynamic structure and the model of flight control system of a certain kind of HSV, the ideal nonlinear generalized predictive control (NGPC) law based on uncertain nonlinear model is raised first to optimize the receding-horizon criterion of tracking errors. Then the online support vector regression (SVR) is employed to identify the uncertain item in the ideal control law. It is the compensating part of the controller. In addition, the stability of the close-loop system is analyzed using the Lyapunov method. The developed control strategy is well-implemented in this HSV attitude control system, and the simulation results compared with both nominal NGPC and RBF neural network disturbance observer show the good robustness and disturbance attenuation ability of this strategy and demonstrate the efficiency of online SVR algorithm.

关键词： hypersonic vehicle flight control nonlinear generalized predictive control online support vector regression

Discoursing on Soxhlet extraction of ginseng using association analysis and scanning electron microscopy

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Journal of Pharmaceutical Analysis 2018年第5期8卷 312-317页

作者： Yuan Yue Zi-Dong Qiu Xian-You Qu Ai-Ping Deng Yuan Yuan Lu-Qi Huang chang-jiang-sheng Lai Chongqing Academy of Chinese Materia Medica Chongqing Key Laboratory of Traditional Chinese Medicine ResourcesChongqing Sub-center of National Resource Center for Chinese Materia MedicaChina Academy of Chinese Medical SciencesChongqing 400065PR China National Resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesState Key Laboratory Breeding Base of Dao-di HerbsBeijing 100700PR China State Key Laboratory of Natural Medicines(China Pharmaceutical University) No.24 Tongjia laneNanjing 210009PR China

Soxhlet extraction is a common method of sample preparation. However, there has been no discussion about the efficiency of Soxhlet extraction from different batches and the factors that cause content fluctuation. In this study, Panax ginseng was selected as a model sample. Soxhlet extraction by means of a water bath, which has always been neglected, was identified as a novel key factor in the poor repeat- ability in different batches of Soxhlet extraction, as it can affect the siphon times and reflux time, which have been positively correlated with the ginsenoside contents. By substituting round bottom flasks in the same column, the relative standard deviation of the most fluctuated compound, ginsenoside Rbl, was decreased from 24.6% to 5.02%. Scanning electron microscopy analysis confirmed that the breakdown of the surface of the ginseng powder in the Soxhlet extraction led to a better dissolution of ginsenosides, indicating that chloroform may promote the extraction of ginsenosides by disrupting the cell structure. Moreover, 70% methanol was regarded as the better solvent for extracting the ginsenosides. Overall, this work offers a practical and effective protocol for improving the accuracy and repeatability of Soxhlet extraction methodology for ginsenosides and other analytes.

关键词： Ginseng Ginsenosides Soxhlet extraction Repeatability Siphon times

Real-time toxicity prediction of Aconitum stewing system using extractive electrospray ionization mass spectrometry

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Acta Pharmaceutica Sinica B 2020年第5期10卷 903-912页

作者： Zi-Dong Qiu Jin-Long Chen Wen Zeng Ying Ma Tong Chen Jin-Fu Tang chang-jiang-sheng Lai Lu-Qi Huang State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China National Resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesState Key Laboratory Breeding Base of Dao-di HerbsBeijing 100700China

Due to numerous obstacles such as complex matrices,real-time monitoring of complex reaction systems(e.g.,medicinal herb stewing system)has always been a challenge though great values for safe and rational use of ***,facilitated by the potential ability on the tolerance of complex matrices of extractive electrospray ionization mass spectrometry,a device was established to realize continuous sampling and real-time quantitative analysis of herb stewing system for the first time.A complete analytical strategy,including data acquisition,data mining,and data evaluation was proposed and implemented with overcoming the usual difficulties in real-time mass spectrometry *** complex Fuzi(the lateral root of Aconitum)-meat stewing systems were real-timely monitored in150 min by qualitative and quantitative analysis of the nine key alkaloids *** results showed that the strategy worked perfectly and the toxicity of the systems were evaluated and predicated *** with trotters effectively accelerated the detoxification of Fuzi soup and reduced the overall toxicity to 68%,which was recommended to be used practically for treating rheumatic arthritis and enhancing *** established strategy was versatile,simple,and accurate,which would have a wide application prospect in real-time analysis and evaluation of various complex reaction systems.

关键词： Real-time extractive electrospray ionization mass spectrometry Toxic alkaloids Data mining Aconitine Aconitum--meat stewing system Toxicity prediction

THE DESIGN AND SIMULATION OF AN INTELLIGENCE FLIGHT CONTROL SYSTEM

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Chinese Journal of Aeronautics 1992年第2期 113-120页

作者： jiang chang-sheng,Shen Chun-lin,Hu Zhong-han(Nanjing Aeronautical Institute)

In this paper,the design of an intelligence automatic flight control system *** basic structure of the system,,the basic rules of intelligence control for simulatingthe human behaviour,the division of characteristic models and the construction ofintelligence control laws are *** on the principles mentioned above,the knowledgebase,the data base,the rule base and the inference mechanism of the system forsome kind of aircraft are *** the meanwhile,it is demonstrated by digitalsimulation that this system has excellent control performance,strong robustness andadaptability,and good decoupling function.

关键词： THE DESIGN AND SIMULATION OF AN INTELLIGENCE FLIGHT CONTROL SYSTEM

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一类四维混沌系统切换混沌同步

物理学报 2007年第2期56卷 707-712页

作者：刘扬正姜长生林长圣南京航空航天大学自动化学院南京210016 南京工程学院非线性物理研究所南京210013

构建了一类可切换的四维混沌系统,通过选择器实现这类系统间的随机切换.简要地分析了四维混沌系统平衡点的性质、混沌吸引子的相图和Lyapunov指数等特性,并设计了实现四维混沌系统切换的实际电路.利用非线性反馈控制方法实现了这类系统... 详细信息

构建了一类可切换的四维混沌系统,通过选择器实现这类系统间的随机切换.简要地分析了四维混沌系统平衡点的性质、混沌吸引子的相图和Lyapunov指数等特性,并设计了实现四维混沌系统切换的实际电路.利用非线性反馈控制方法实现了这类系统与其中某个系统之间的切换混沌同步.根据系统稳定性理论,得到了非线性反馈控制器的结构和系统达到混沌同步时反馈控制增益的取值范围.

关键词：非线性反馈混沌同步四维混沌系统

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一类关联混沌系统的分时切换混沌同步

物理学报 2008年第2期57卷 709-713页

作者：刘扬正姜长生林长圣南京航空航天大学自动化学院南京210016 南京工程学院非线性物理研究所南京211167

提出关联混沌系统分时切换混沌同步的思想.利用线性反馈控制方法实现一类关联混沌系统中各个子系统与其复制系统间的分时切换混沌同步.根据时变系统的稳定性理论,得到了使各子系统都能实现混沌同步的反馈控制增益的取值范围.数值仿真实... 详细信息

提出关联混沌系统分时切换混沌同步的思想.利用线性反馈控制方法实现一类关联混沌系统中各个子系统与其复制系统间的分时切换混沌同步.根据时变系统的稳定性理论,得到了使各子系统都能实现混沌同步的反馈控制增益的取值范围.数值仿真实验证明了理论分析的正确性和可行性.

关键词：分时切换混沌同步线性反馈关联混沌系统

错位修正混沌函数投影同步及在保密通信中的应用

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四川大学学报（工程科学版） 2011年第2期43卷 136-141,149页

作者：方洁姜长生南京航空航天大学自动化学院江苏南京210016 郑州轻工业学院电气信息工程学院河南郑州450002

研究了一种新的错位修正混沌函数投影同步控制方法及其保密通信应用。基于Lyapunov稳定性理论和主动控制方法,设计非线性反馈控制器和参数更新规则,实现了两个同结构的超混沌系统的不同状态变量之间的错位修正函数投影同步并估计出未知... 详细信息

研究了一种新的错位修正混沌函数投影同步控制方法及其保密通信应用。基于Lyapunov稳定性理论和主动控制方法,设计非线性反馈控制器和参数更新规则,实现了两个同结构的超混沌系统的不同状态变量之间的错位修正函数投影同步并估计出未知参数。将此方法用于基于混沌遮掩调制的保密通信中。信息信号经过函数转换后被驱动系统状态变量遮掩并作为驱动信号传送到接受端,在接受端通过消除函数尺度因子和反函数变换对信息信号进行恢复。该控制策略具有较强的保密性和实用性。数值仿真证明了该控制方法的有效性。

关键词：超混沌系统错位修正函数投影同步自适应保密通信