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Finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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Science china(Information sciences) 2024年第6期67卷 279-296页

作者： Yana YANG Huixin JIANG changchun HUA Junpeng LI institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are *** and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) ***, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ***, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, china {2., chinese academy of sciences, changchun 13002., china chemistry and Chemical Engineering College of Henan University Kaifeng China changchun institute of {2. chemistry Chinese Academy of Sciences Changchun China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

MELTING CRYSTALLIZATION BEHAVIOR OF NYLON 66

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chinese Journal of Polymer Science 2001年第3期19卷 237-246页

作者： Qing-xin Zhang Zhi-shen Mo State Key Laboratory of Polymer Physics & chemistry changchun {2. of applied chemistry chinese academy of sciences, changchun 13002., china 中科院长春应用化学所高分子物理与化学国家重点实验室吉林长春

Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differential scanning calorimetry (DSC). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, to fit the primary stage of isothermal and nonisothermal crystallizations of nylon 66. In the isothermal crystallization process, mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determined from the Lauritzen-Hoffman treatment are sigma = 9.77 erg/cm(2. and sigma (e) = 155.48 erg/cm(2., respectively; and the work of chain folding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo method combined with the Avrami and Ozawa equations. The average Avrami exponent (n) over bar was determined to be 3.45. The activation energies (DeltaE) were determined to be -485.45 kJ/mol and -331.2. kJ/mol, respectively, for the isothermal and nonisothermal crystallization processes by the Arrhenius and the Kissinger methods.

关键词： nylon 66 crystallization kinetics activation energy

Luminescence of RE^(3+) and energy transfer from Gd^(3+) to RE^(3+) (RE = Dy, Eu) in SrGdAlO_4:RE^(3+)

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chinese Journal of chemistry 1997年第1期15卷 60-67页

作者： LIU, Sheng-Li SU, QiangLaboratory of Rare Earth chemistry and Physics, changchun {2. of applied chemistry, chinese academy of sciences, changchun, Jilin 13002., china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail. A cooperative vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2. 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.

关键词： Luminescence energy transfer rare earth aluminate

Characterizing structural variants based on graph-genotyping provides insights into pig domestication and local adaption

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Journal of Genetics and Genomics 2024年第4期51卷 394-406页

作者： Xin Li Quan Liu Chong Fu Mengxun Li changchun Li Xinyun Li Shuhong Zhao Zhuqing Zheng Key Lab of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education and Key Laboratory of Swine Genetics and Breeding of Ministry of AgricultureCollege of Animal Science and TechnologyHuazhong Agricultural UniversityWuhanHubei 430070China institute of Agricultural Biotechnology Jingchu University of TechnologyJingmenHubei 448000China The Cooperative Innovation Center for Sustainable Pig Production WuhanHubei 430070China Hubei Hongshan Laboratory WuhanHubei 430070China

Structural variants(SVs),such as deletions(DELs)and insertions(INSs),contribute substantially to pig genetic diversity and phenotypic *** a library of SVs discovered from long-read primary assemblies and short-read sequenced genomes,we map pig genomic SVs with a graph-based method for re-genotyping SVs in 402.*** results demonstrate that those SVs harboring specific trait-associated genes may greatly shape pig domestication and local *** characterization of SVs reveals that some population-stratified SVs may alter the transcription of genes by affecting regulatory *** identify that the genotypes of two DELs(2.6-bp DEL,chr7:52.172.101e52.172.397;2.8-bp DEL,chr18:2.,840,143 e2.,840,42.)located in muscle-specific enhancers are associated with the expression of target genes related to meat quality(FSD2.and muscle fiber hypertrophy(LMOD2.and WASL)in *** results highlight the role of SVs in domestic porcine evolution,and the identified candidate functional genes and SVs are valuable resources for future genomic research and breeding programs in pigs.

关键词： Pigs Structural variation Selection signatures Regulatory elements

Study on green power supply modes for heavy load in Remote Areas

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Global Energy Interconnection 2024年第4期7卷 475-485页

作者： Yu Li Yixi Cuomu Yiming Gao Guoqin Lv Weiwei Lin Sirui Li changchun Zhou State Grid Xizang Electric Power Co. Ltd.Lhasa 850010Tibet Autonomous RegionP.R.China Global Energy Interconnection Development and Cooperation Organization Beijing 100031P.R.China State Grid Fujian Power Economic Research institute Fuzhou 350012P.R.China Eindhoven University of Technology Eindhoven.5621 AENetherlands

In this study,the present situation and characteristics of power supply in remote areas are *** studying the cases of power supply projects in remote areas,the experience is analyzed and described,and the applicability of related technologies,such as grid-forming storage and power load management,is studied,including grid-connection technologies,such as grid-forming converters and power load *** this basis,three power-supply modes were *** application scenarios and advantages of the three modes were compared and *** on the local development situation,the temporal sequences of the three schemes are described,and a case study was *** study of the heavy-load power supply mode in remote areas contributes to solving the problem of heavy-load green power consumption in remote areas and promoting the further development of renewable energy.

关键词： Remote area Renewable energy Grid-forming storage Power load management Power supply mode

Study on polymerization and structure of polydiphenylamine

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chinese Journal of chemistry 1994年第2期12卷 138-147页

作者： JIN, Wen SONG, Fa-Yi DONG, Shao-JunLaboratory of Electroanalytical chemistry, changchun {2. of applied chemistry, chinese academy of sciences, changchun, Jilin 13002., china Laboratory of Electroanalytical chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

The electrochemical oxidation of diphenylamine in acetonitrile produces an adherent uniform polymer film which exhibits mutiple colour variation(yellow-green-blue) in a wide range of potential scan. The polymerization mechanism and the structure of the polymer were studied by cyclic voltammetry, FT-IR and in situ ESR. The results indicate that the electrochemical polymerization of diphenylamine belongs to a cationic radical polymerization process. During electrolysis, only oligomers were initialy produced, then polymer film was formed on the electrode surface. The electropolymerization performs via the 4,4' C-C phenyl-phenyl coupling mechanism.

关键词： DPA electrochemical polymerization mechanism ESR.

Portable fluorescence instrument for detecting membrane integrity in membrane bioreactor (MBR)

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 121-131页

作者： Yang Yu changchun Xin Yuxiang Liu Fei Gao Lei Zhang Hui Jia Jie Wang State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tianjin UniversityTianjin 300072China Shenyang academy of Environmental sciences Shenyang 110167China Cangzhou institute of Tiangong University Tiangong UniversityCangzhou 061000China

This study proposed the design, fabrication, and assembly of membrane integrity detection instruments in membrane bioreactors (MBR) based on fluorescence spectroscopy. Based on the PARAFAC model, we found that the peak at 2.0/335 nm strengthened after membrane breakage. The peak at 340/430 nm reflected the sludge concentration in the MBR and reduced the influence of internal filtration effects on detection. Therefore, we determined that the dual-LED light source excitation detection system can detect tryptophan-like substances at 2.0 nm (T-peak) and humic acid at 340 nm (C-peak). T-peak was identified as the core index indicating membrane integrity. Moreover, the C-peak is the reference indicator factor for a sensitive response to changes in the sludge concentration. The portable fluorescence instrument exhibited high sensitivity and good feedback accuracy compared to particle counting and turbidity detection, where the log reduction value was greater than 3.5. This overcomes the disadvantage of false alarms in particle counters and is not affected by the position of the pump system. This portable instrument provides a flexible and highly sensitive method for the assessment of industrial membrane integrity.

关键词： Membrane integrity Fluorescence spectrum Portable instrument Membrane bioreactor

Luminescent properties of Ba_3(PO_4)_2.Eu,Tb phosphors

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chinese Journal of chemistry 1996年第5期14卷 399-403页

作者： GAO,Yong SHI,Chun-ShanLaboratory of Rare Earth chemistry and Physics,changchun {2. of applied chemistry,chinese academy of sciences,changchun,Jilin 13002.,china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Luminescence of europium (Ⅲ),europium(Ⅱ) and terbium(Ⅲ) has been observed in Bas(PO4)2.Eu,Tb phosphors which are synthesized in air *** valence state of europium is influenced by amount of *** is notable that the relative intensity of the emission spectra peaks corresponding to Eu2. is increased if the amount of Tb3+ is *** phenomena can be explained by an electron transfer *** predict a new kind of two-rare-earth codoped trichromatic phosphors in Ba3(PO4)2.matrix.

关键词： Luminescence europium terbium phosphor