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Sensor Fault Diagnosis for a Class of Time Delay Uncertain Nonlinear Systems Using Neural Network

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International Journal of Automation and computing 2008年第4期5卷 401-405页

作者： Mou Chen chang-sheng jiang Qing-Xian Wu College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016PRC

In this paper,a sliding mode observer scheme of sensor fault diagnosis is proposed for a class of time delay nonlinear systems with input uncertainty based on neural *** sensor fault and the system input uncertainty are assumed to be unknown but *** radial basis function (RBF) neural network is used to approximate the sensor *** on the output of the RBF neural network,the sliding mode observer is *** the Lyapunov method,a criterion for stability is given in terms of matrix ***,an example is given for illustrating the availability of the fault diagnosis based on the proposed sliding mode observer.

关键词： Uncertain nonlinear system time delay radial basis function (RBF) neural network sliding mode observer fault diag-nosis.

Synthesis and Crystal Structure of 4-(4-Bromophenyl)- 3,4-dihydro-6-methyl quinolin-2(1H)-one

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Chinese Journal of Structural Chemistry 2007年第5期26卷 533-536页

作者： YU Chen-Xia ZHU Xiao-Tong YAO chang-sheng TU Shu-jiang Department of Chemistry Xuzhou Normal University Xuzhou 221116 China Key Laboratory of Biotechnology for Medical Plants of jiangsu Province Xuzhou 221116 China

The title compound （C16H14BrNO） has been synthesized by the reaction of p-tolylamine, Meldrum’s acid and 4-bromo-benzaldehyde, and its structure was characterized by IR, 1H NMR and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 7.6850（11）, b = 8.3004（11）, c = 21.301（3）A, β = 95.110（2）°, V = 1353.4（3） A^3, Mr = 316.19, Z = 4, Dc = 1.552 g/cm^3, μ（MoKα） = 3.028 mm-1, F（000） = 640, the final R = 0.0345 and wR = 0.0768. X-ray analysis reveals that the atoms of C（1）, C（2）, C（3）, C（4）, C（5） and N（1） form a six-membered ring of boat conformation.

关键词： quinoline crystal structure

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

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Chinese Chemical Letters 2002年第12期13卷 1143-1146页

作者： chang sheng jiang You Gui LI Chen jiang Fang WANG Tian Pa YOU Department of Chemistry Universtity of Science&Technology of ChinaHefei 230026

Four stereoisomers of a copper-(Schiff-base) complex with double chiral centers were applied to catalyze the asymmetric cyclopropanation. Two of the stereoisomers were also efficient catalysts affording high enantiom... 详细信息

关键词： Asymmetric cyclopropanation copper-(Schiff-base) olefins diazoacetates.

A New Synthesis of 4, 4-Diaryl/Diheteroaryl-3-butenyl Derivatives of Nipecotic Acids as GABA Transporter Inhibitors

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Chinese Chemical Letters 2005年第9期16卷 1205-1208页

作者： Jian Ge ZHANG chang sheng jiang Guo Qiang LIN Ren WEN Department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 Shanghai Institute of Organic Chemistry Chinese Academy of Sciences shanghai 200032

A new method for the synthesis of 4, 4-diaryl/diheteroaryl-3-butenyl derivatives of nipecotic acid as GABA transporter inhibitors is described. The key intermediates 4-tosyl-1, 1-diaryl/diheteroaryl-1-butene 10a-d were synthesized by Wittig reaction, and followed by alkylation with （R）-3-piperidinecarboxylate. The resulting N-cycloalkylated amino acid esters 11a-d were saponified and then acidified to get the target compounds 1a-d. The preliminary bioassays showed that la-d exhibited excellent inhibition of [3H]-GABA uptake in vitro of culture cells.

关键词： Tiagabine nipecotic acid derivatives synthesis GABA transporter inhibitor

Design of supercontinuum source for coherent anti-Stokes Raman scattering microscopy

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Optoelectronics Letters 2008年第2期4卷 103-105页

作者： ZHANG Hui chang sheng-jiang ZHANG Yan-xin ZHAO Xiang-ting Institute of Modern Optics Key Laboratory for Optoelectronic Information Technical Science of Education Ministry of China Nankai University Tianjin 300071 China

A new method to obtain supercontinuum(SC) source for multiplex coherent anti-stokes Raman scattering (CARS) microscopy is proposed. The nonlinear propagation in photonic-crystal fibers (PCF) of femtosecond pulse laser with central wavelength at 800.9 nm is studied with scalar wave theory. Based on the incident laser power and dispersion of PCF, super broadband source for multiplex CARS microscopy is designed.

关键词：超级连续资源拉曼理论散射显微镜光纤器械

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

Atrial fibrillation in China： a brief review

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Chinese Medical Journal 2009年第23期122卷 2803-2806页

作者： MA chang-sheng DU Xin jiang Chen-xi Department of Cardiology/Atrial Fibrillation Center Beijing Anzhen Hospital Capital Medical University Beijing 100029China

Atrial fibrillation （AF） is the most common heart .rhythm disturbance encountered in clinical *** affects at least ten million Chinese, constituting a major public health epidemic. For the shortness of resource in the initial stage of new China and the chaos during the culture revolution, there was a scarcity of AF data on the Chinese population. However, Chinese physicians had never stopped exploring in this field, which has provided a solid foundation for today＇s flourishing development in the research of AF. This paper aims to review the major achievements in dealing with AF in the past 60 years in China, especially in the latest 15 years.

关键词： atrial fibrillation epidemiology anticoagulation antiarrhythmic drug catheter ablation

Quantum Mechanical Nature in Liquid NMR Quantum Computing

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Communications in Theoretical Physics 2002年第3期38卷 305-308页

作者： LONG Gui-Lu YAN Hai-Yang LI Yan-Song TU chang-Cun ZHU sheng-jiang RUAN Dong SUN Yang TAO Jia-Xun CHEN Hao-Ming Department of Physics Tsinghua University Beijing 100084 China Laboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Center for Atomic and Molecular Nano-Sciences Tsinghua University Beijing 100084 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Department of Physics Tsinghua University Beijing 100084 ChinaLaboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 ChinaLaboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 ChinaLaboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China Laboratory for Quantum Computation and Quantum Measurement Beijing 100084 China Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996 USA Department of Chemistry Tsinghua University Beijing 100084 China Department of Physics Tsinghua University Beijing 100084 China

The quantum nature of bulk ensemble NMR quantum computing the center of recent heated debate,is addressed. Concepts of the mixed state and entanglement are examined, and the data in a two-qubit liquid NMRquantum computation are analyzed. The main points in this paper are: i) Density matrix describes the "state" of anaverage particle in an ensemble. It does not describe the state of an individual particle in an ensemble; ii) Entanglementis a property of the wave function of a microscopic particle (such as a molecule in a liquid NMR sample), and separabilityof the density matrix cannot be used to measure the entanglement of mixed ensemble; iii) The state evolution in bulk-ensemble NMRquantum computation is quantum-mechanical; iv) The coefficient before the effective pure state densitymatrix, e, is a measure of the simultaneity of the molecules in an ensemble. It reflects the intensity of the NMR signaland has no significance in quantifying the entanglement in the bulk ensemble NMR system. The decomposition of thedensity matrix into product states is only an indication that the ensemble can be prepared by an ensemble with theparticles unentangled. We conclude that effective-pure-state NMR quantum computation is genuine, not just classicalsimulations.

关键词： quantum mechanical nature, NMR quantum computing, mixed state, entanglement