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Theoretical Analysis of Rayleigh Backscattering Noise in Fiber Raman Amplifiers

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Communications in Theoretical Physics 2005年第5X期44卷 908-910页

作者： sheng zhao-Xia Department of Mathematics and Physical Science Tianjin University of Technology and Education Tianjin 300222 China

In this paper, a new theoretical model for Rayleigh backscattering (RB) analysis of fiber Raman amplifiers is proposed. The model includes all the interactions among the pumps, signals, and all orders of RB. The results show that the higher order RB has a negligible influence on the performance of the amplifier. The co-propagating and counterpropagating RB power of the signal grow quadratically with the net-gain of the amplifier. The signal to double Rayleigh backscattering noise ratio (OSNRDRB ) of backward-pumped FRAs is better than that of the forward-pumped ones at high net-gain level (＞ 13 dB), while at low net-gain level the OSNRDrb of the forward-pumped FRAs is slightly better than that of the backward-pumped ones.

关键词： fiber Raman amplifier Rayleigh scattering

Design study of APS-U-type hybrid-MBA lattice for mid-energy DLSR

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Nuclear Science and Techniques 2021年第7期32卷 46-54页

作者： Yu zhao Yi Jiao sheng Wang Institute of High Energy Physics(IHEP) Chinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Spallation Neutron Source Science Center(SNSSC) Dongguan 523803China

In recent years,a new generation of storage ring-based light sources,known as diffraction-limited storage rings(DLSRs),whose emittance approaches the diffraction limit for the range of X-ray wavelengths of interest to the scientific community,has garnered significant attention *** have begun to design and build *** various DLSR proposals,the hybrid multibend achromat(H-MBA)lattice enables sextupole strengths to be maintained at a reasonable level when minimizing the emittance;hence,it has been adopted in many DLSR *** on the H-7BA lattice,the design of the Advanced Photon Source Upgrade Project(APS-U)can effectively reduce emittance by replacing six quadrupoles with ***,we discuss the feasibility of designing an APS-U-type H-MBA lattice for the Southern Advanced Photon Source,a mid-energy DLSR light source with ultralow emittance that has been proposed to be built adjacent to the China Spallation Neutron *** linear and nonlinear dynamics are optimized to obtain a detailed design of this type of *** emittance is minimized,while a sufficiently large dynamic aperture(DA)and momentum acceptance(MA)are maintained.A design comprising 36 APS-U type H-7BAs,with an energy of 3 GeV and a circumference of 972 m,is *** horizontal natural emittance is 20 pm·rad,with a horizontal DA of 5.8 mm,a vertical DA of 4.5 mm,and an MA of 4%,as well as a long longitudinal damping time of 120 ***,a few modifications are performed based on the APS-U-type lattice to reduce the maximum value of damping time from 120 to 44 ms while maintaining other performance parameters at the same level.

关键词： Southern advanced photon source(SAPS) Diffraction-limited storage ring(DLSR) Hybrid multibend achromat(H-MBA) Advanced photon source upgrade project(APS-U) Lattice design

Dynamic Response of 6MW Spar Type Floating Offshore Wind Turbine by Experiment and Numerical Analyses

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China Ocean Engineering 2020年第5期34卷 608-620页

作者： MENG Long HE Yan-ping zhao yong-sheng YANG Jie YANGHe HAN zhao-long YU Long MAO Wen-gang DU Wei-kang a State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China b Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration(CISSE) Shanghai Jiao Tong UniversityShanghai 200240China c School of Naval Architecture Ocean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China d China Aerodynamics Research and Development Center Mianyang621000China e Ocean Engineering Department Texas A&M UniversityCollege StationTX 77843USA f Department of mechanics and Maritime Sciences Chalmers University of Technology41296GothenburgSweden g Ocean Engineering Group Department of CivilArchitecture and Environmental EngineeringUniversity of Texas at AustinTexasTX 78712USA

The floating offshore wind turbine(FOWT) is widely used for harvesting marine wind energy. Its dynamic responses under offshore wind and wave environment provide essential reference for the design and installation. In this study,the dynamic responses of a 6 MW Spar type FOWT designed for the water depth of 100 m are investigated by means of the wave tank experiment and numerical analysis. A scaled model is manufactured for the experiment at a ratio of65.3, while the numerical model is constructed on the open-source platform FAST(Fatigue, Aerodynamics,Structures, and Turbulence). Still water tests, wind-induced only tests, wave-induced only tests and combined windwave-current tests are all conducted experimentally and numerically. The accuracy of the experimental set-up as well as the loading generation has been verified. Surge, pitch and heave motions are selected to analyze and the numerical results agree well with the experimental values. Even though results obtained by using the FOWT calculation model established in FAST software show some deviations from the test results, the trends are always consistent. Both experimental and numerical studies demonstrate that they are reliable for the designed 6 MW Spar type FOWT.

关键词： floating offshore wind turbine dynamic responses Spar type platform FAST model test

猪繁殖与呼吸综合征病毒核衣壳蛋白的原核可溶性表达和间接ELISA抗体检测方法的初步建立

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中国兽医科学 2018年第4期48卷 419-427页

作者：王俊代军飞马炳丁耀忠欧云文刘永生赵乐辉张永光张杰中国农业科学院兰州兽医研究所家畜疫病病原生物学国家重点实验室/国家口蹄疫参考实验室甘肃兰州730046 辽东学院农学院辽宁丹东118003 江苏省动物重要疫病与人兽共患病防控协同创新中心江苏扬州225009

猪繁殖与呼吸综合征病毒（porcine reproductive and respiratory syndrome virus，PRRSV）的核衣壳蛋白N是一种含量高、免疫原性强、最早刺激机体产生特异性抗体的主要结构蛋白，研制针对N蛋白抗体的检测方法对进一步实现PRRS的流行病... 详细信息

猪繁殖与呼吸综合征病毒（porcine reproductive and respiratory syndrome virus，PRRSV）的核衣壳蛋白N是一种含量高、免疫原性强、最早刺激机体产生特异性抗体的主要结构蛋白，研制针对N蛋白抗体的检测方法对进一步实现PRRS的流行病学监测和诊断具有重要意义。本研究以带有MBP标签的pMAL—C4X作为表达载体。实现了N蛋白在大肠杆菌中的可溶性表达，每升菌液经纯化可得约20mg的融合N蛋白。Western—blot结果表明．融合N蛋白能被抗MBP的单抗和PRRSVN蛋白的家兔多抗特异识别。以融合N蛋白为包被抗原建立的间接ELISA方法不与猪圆环病毒2型（PCV2）、古典猪瘟病毒（CSFV）、伪狂犬病病毒（PRV）、猪细小病毒（PPV）的阳性猪血清发生交叉反应，但与1型PRRSV阳性猪血清有较强反应性。田间样品检测结果表明。本研究建立的间接ELISA抗体检测方法与IDEXX同类试剂盒的总符合率为90％左右。本研究以MBP作为促溶标签，实现了PRRSVN蛋白在大肠杆菌内的高效可溶性表达，重组蛋白具有良好的免疫反应性．这为深入研究N蛋白功能以及开发PRRS相关诊断制剂奠定了基础。

关键词：猪繁殖与呼吸综合征病毒核衣壳蛋白原核可溶性表达间接ELISA 抗体检测

Observer-Based Controller Design for Singular Stochastic Markov Jump Systems with State Dependent Noise

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Journal of Systems Science & Complexity 2016年第4期29卷 946-958页

作者： zhao yong ZHANG Weihai College of Electrical Engineering and Automation and College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

This paper is concerned with the problem of observer-based controller design for singular stochastic Markov jump systems with state-dependent noise. Two concepts called "non-impulsiveness"and "mean square admissibility" are introduced, which are different from previous ones. Sufficient conditions for the open-and closed-loop singular stochastic Markov jump systems with state-dependent noise to be mean square admissible are provided in terms of strict LMIs. The controller gain and the observer gain which guarantee the resulting closed-loop error system to be mean square admissible are obtained in turn by solving the strict LMIs. A numerical example is presented to show the efficiency of the design approach.

关键词： Linear matrix inequalities observer-based controller singular stochastic systems stability.

Multi-attribute decision making model based on optimal membership and relative entropy

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Journal of Systems Engineering and Electronics 2009年第3期20卷 537-542页

作者： Rao Congjun zhao yong Inst. of Systems Engineering Huazhong Univ. of Science and Technology Wuhan 430074 P. R. China Coll. of Mathematics and Information Science Huanggang Normal Univ. Huanggang 438000 P. R. China

To study the problems of multi-attribute decision making in which the attribute values are given in the form of linguistic fuzzy numbers and the information of attribute weights are incomplete, a new multi-attribute decision making model is presented based on the optimal membership and the relative entropy. Firstly, the definitions of the optimal membership and the relative entropy are given. Secondly, for all alternatives, a set of preference weight vectors are obtained by solving a set of linear programming models whose goals axe all to maximize the optimal membership. Thirdly, a relative entropy model is established to aggregate the preference weight vectors, thus an optimal weight vector is determined. Based on this optimal weight vector, the algorithm of deviation degree minimization is proposed to rank all the alternatives. Finally, a decision making example is given to demonstrate the feasibility and rationality of this new model.

关键词： multi-attribute decision making optimal membership relative entropy deviation degree

A new free recoverable and reusable mono-alkaloid-type ligand and its use in preparation of ethyl(2R,3S)-2,3-dihydroxy-3-phenylpropionate

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Chinese Chemical Letters 2009年第7期20卷 763-766页

作者： Qiao Feng Wang Hui Chen Yan zhao Xiao Ye Li sheng yong Zhang Research Center of Chirotechnology Fourth Military Medical University Xi'an 710032 PR China

A new free recoverable and reusable mono-alkaloid-type ligand has been synthesized by a simple method. With highly polar groups, the ligand can be recycled and reused eight times to prepare ethyl （2R,3S）-2,3-dihydroxy-3-phenylpropionate with high yield and ee via asymmetric dihydroxylation （AD） reaction. C 2009 sheng yong Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cinchona alkaloid Recoverable and reusable ligand Ethyl (2R,3S)-2,3-dihydroxy-3-phenylpropionate

Chiral covalent organic frameworks for asymmetric catalysis and chiral separation

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Science China Chemistry 2017年第8期60卷 1015-1022页

作者： Liu,Guofeng sheng,Jianhui zhao,Yanli Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore Department of Macromolecular Science Fudan University Shanghai 200433 China

Covalent organic frameworks(COFs), covalently assembled from the condensation reactions of organic building blocks, are a fascinating class of functional porous materials with two-or three-dimensional crystalline organic structures. Generally, it is preferable to use symmetric and rigid building blocks to construct highly crystalline COFs with desired topology. On the other hand, the incorporation of chiral functional moieties in the building blocks would open up new applications such as asymmetric catalysis and chiral separation. This mini review highlights the principle strategies in the design and synthesis of chiral COFs. The interesting and potential applications of these chiral COFs for asymmetric catalysis and chiral separation are also *** mini review aims to provide an up-to-date advancement of chiral COFs for asymmetric catalysis and chiral separation.

关键词： asymmetric catalysis building blocks chiral separation covalent organic frameworks porous materials

Establishment of an animal model of ischemic type intrahepatic biliary lesion in rabbits

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World Journal of Gastroenterology 2009年第6期15卷 732-736页

作者： Qin-song sheng Da-Zhi Chen Ren Lang Qiang He yong-Jiu Yang zhao-Wei Qu De-Fang zhao Xiao-sheng Zhang Department of Hepatobiliary and Pancreatosplenic Surgery Beijing Chaoyang Hospital affiliated to the Capital Medical University Beijing 100020 China

AIM:To explore a method to establish an animal model of ischemic type intrahepatic biliary lesion in rabbits. METHODS:Forty Japanese white rabbits of clean grade were divided randomly into four groups(10 rabbits per group)including sham operation(SO) group,and artery-bile obstruction(ABO)-1 h group, ABO-2 h group and ABO-3 h *** the rabbits in this study underwent the same initial surgical procedure in which the liver was prepared as for graft removal during liver *** in the SO group,no additional vascular intervention was performed,while in groups ABO-1 h,ABO-2 h and ABO-3 h,the animals underwent combined clamping of the hepatic artery and common bile duct with microvascular clips for 1,2 and 3 h,*** the scheduled occlusion time,the clip was removed to recover blood *** animals were killed 4 wk after *** survival rate,liver function, cholangiography and histopathological manifestation of the rabbits in each group were observed. RESULTS:The survival rate was 100%in groups SO,ABO-1 h and ABO-2 h,while it was 60%in group ABO-3 *** each observation time,the change degree of the indexes of liver function was proportional to the clamping time(ABO-3 h>ABO-2 h>ABO-1 h> SO,P<0.05).Cholangiographical and histopathologic manifestations both showed that intrahepatic biliary lesion aggravated proportionally with the increase of the clamping time. CONCLUSION:An animal model of ischemic type intrahepatic biliary lesion in rabbits is successfully established,which may provide a reliable technique for basic and clinical research into the etiology, development and prophylaxis of ischemic type intrahepatic biliary lesion after liver transplantation.

关键词： Biliary complication Ischemic type biliary lesion Animal model Liver transplantation Intrahepatic biliary stricture Ischemic reperfusion injury