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Quasi-synchronous control of uncertain multiple electrohydraulic systems with prescribed performance constraint and input saturation

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Chinese Journal of Aeronautics 2023年第9期36卷 416-425页

作者： shuai li qing guo yan shI Yao yan Dan jiang School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Science and Electrical engineering Beihang UniversityBeijing 100191China School of Mechanical and Electrical engineering University of Electronic Science and Technology of ChinaChengdu 611731China

This article focuses on the high accuracy quasi-synchronous control issue of multiple electrohydraulic systems(MEHS).In order to overcome the negative effects of parameter uncertainty and external load interference of MEHS,a kind of finite-time disturbance observer(FTDO)via terminal sliding mode method is constructed based on the MEHS model to achieve fast and accuracy estimation and compensation *** avoid the differential explosion in backstepping iteration,the dynamic surface control is used in this paper to guarantee the follower electrohydraulic nodes synchronize to the leader motion with a better ***,a timevarying barrier Lyapunov function(tvBLF)is adopted during the controller design process to constraint the output tracking error of MEHS in a prescribed performance with time-varying exponential *** the initial state condition is relax by tvBLF,the input saturation law is also adopted during the controller design process in this paper to restrain the surges of input signals,which can avoid the circuit and mechanical structure damage caused by the volatile input *** MEHS experimental bench is constructed to verify the effectiveness of the theoretical conclusions proposed in this paper and the advantages of the proposed conclusions in this paper are illustrated by a series of contradistinctive experimental results.

关键词： Backstepping Dynamic surface Finite-time disturbance observer Input saturation Multiple Electrohydraulic Systems Output error constraint Quasi-synchronous control

Electrochemistry of Hf(Ⅳ)in NaCl-KCl-Na-K_(2)HfF_(6) molten salts

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International Journal of Minerals,Metallurgy and Materials 2020年第12期27卷 1644-1649页

作者： yan-ke Wu guo-qing yan Song Chen li-jun wang GRINM Resources and Environment Tech.Co. LtdBeijing 101407China

The cathodic reduction mechanism of Hf(Ⅳ)ions in a fused Na Cl–KCl–Na F–K_(2) HfF_(6) salt system was studied in various Na F concentrations at 1073 K to obtain a purified dendritic Hf *** results of cyclic voltammetry and square wave voltammetry indicated that the reduction process comprised two steps of Hf(Ⅳ)→Hf(Ⅱ)and Hf(Ⅱ)→Hf at low Na F concentrations(0

关键词： electrochemical behavior cyclic voltammetry potentiostatic electrolysis dendritic hafnium molten salts

Quinolinyl Imidazolidin-2-imine Nickel Catalyzed Efficient Copolymerization of Norbornene with para-Chlorostyrene

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Chinese Journal of Polymer Science 2020年第9期38卷 941-949,I0005页

作者： yan-qing li Jian Zhou Ru xiao Zheng-guo Cai State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Material Science and EngineeringDonghua UniversityShanghai 201620China College of Biological and Chemical engineering Guangxi University of Science and TechnologyLiuzhou 545006China

A series of novel quinolinyl imidazolidin-2-imine nickel complexes with different substituents on the imidazolidin-2-imine ligand were synthesized and *** complexes in the presence of methylaluminoxane(MAO)as a cocatalyst catalyzed the copolymerization of norbornene(N)and styrene(S)or para-chlorostyrene(CS)with high activity(up to 1070 kg·mol^-1·h^-1).The installation of sterically bulky substituents on the imidazolidine-2-imine ligand was effective for the increase of the molecular weight and the comonomer content,affording high molecular weight copolymers with tunable CS content(0.57 mol%-11.7 mol%),in which the existence of CI group can provide reaction site for the further functionalization of copolymers as well as the synthesis of graft or cross-linked *** linear relationship between the comonomer content and the glass transition temperature of the copolymers and the monomer reactivity ratios in the copolymerization indicated the formation of the expected functionalized cyclic olefin copolymers(COC).

关键词： Imidazolidin-2-imine ligand Nickel complex Norbornene para-Chlorostyrene Copolymerization

Ectopic Expression of FaDREB2 Enhances Osmotic Tolerance in Paper Mulberry

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Journal of Integrative Plant Biology 2011年第12期53卷 951-960页

作者： Mei-Ru li yan li Hong-qing li guo-jiang Wu Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Xinjiang University Urumqi 830046 China Guangdong Provincial Key Lab of Biotechnology for Plant Development South China Normal University Guangzhou 510631 China

Dehydration-responsive element binding （DREB） proteins are a subfamily of AP2/ERF transcription factors that have been shown to improve tolerance to osmotic stresses in plants. To improve the osmotic stress tolerance of paper mulberry （Broussonetia papyrifera L. Vent）, an economically important tree, we transformed it with a plasmid carrying tall fescue （Festuca arundinacea Schreb） FaDREB2 under the control of CaMV 35S. The ectopic expression of FaDREB2 did not cause growth retardation, and the paper mulberry seedlings expressing FaDREB2 showed higher salt and drought tolerance than wild-type plants （WT）. After 13 d of withholding water, or 15 d in the presence of 250 mM NaCI, all the WT plants died, while the plants expressing FaDREB2 survived. The FaDREB2 transgenic plants had higher leaf water and chlorophyll contents, accumulated more proline and soluble sugars, and had less membrane damage than the WT plants under high salt and water-deficient conditions. Taken together, the results indicate the feasibility of improving tolerance to multiple environmental stresses in paper mulberry seedlings via genetic engineering, by introducing FaDREB2, which promotes the increased accumulation of osmolytes （soluble sugars and proline）, to counter osmotic stresses caused by abiotic factors.

关键词： FaDREB2 Broussonetia papyrifera paper mulberry salt tolerance drought tolerance

Characterization of the chemosensory protein EforCSP3 and its potential involvement in host location by Encarsia formosa

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Journal of Integrative Agriculture 2023年第2期22卷 514-525页

作者： wang Ke HE yan-yan ZHANG You-jun guo Zhao-jiang XIE Wen WU qing-jun wang shao-li Institute of Vegetables and Flowers Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Chemosensory proteins(CSPs) perform several functions in *** study performed the gene expression,ligand-binding,and molecular docking assays on the EforCSP3 identified in the parasitoid wasp Encarsia formosa,to determine whether EforCSP3 functions in olfaction,especially in host location and host *** results showed that EforCSP3 was highly expressed in the female head,and its relative expression was much higher in adults than in other developmental *** fluorescence binding assays suggested that the EforCSP3 exhibited high binding affinities to a wide range of host-related volatiles,among which dibutyl phthalate,1-octene,β-elemene,and tridecane had the strongest binding affinity with EforCSP3,besides α-humulene and β-myrcene,and should be assessed as potential *** structure modeling and molecular docking predicted the amino acid residues of EforCSP3possibly involved in volatile binding.α-Humulene and β-myrcene attracted *** in a previous study and exhibited strong binding affinities with EforCSP3 in the current *** conclusion,EforCSP3 may be involved in semiochemical reception by ***.

关键词： Encarsia formosa chemosensory protein expression profiles fluorescence binding assay molecular docking

Solid solubility extension and microstructure evolution of cast zirconium yttrium alloy

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Rare Metals 2016年第4期35卷 325-330页

作者： Jia-qing Peng yang Chen guo-qing yan Ming Wu li-Jun wang Jing-she li Division of Rare Metals Metallurgy and Materials General Research Institute for Nonferrous Metals School of Metallurgical and Ecological engineering University of Science and Technology Beijing

Yttrium addition can improve the oxidation resistance, mitigate hydrogen embrittlement and thus enhance the mechanical properties of the zirconium alloy. To study solid solubility extension of yttrium in zirconium alloy, the lattice parameters of ：t-Zr phase in Zr-Y alloy were accurately determined by X-ray diffraction （XRD）. Yttrium exhibits solid solubility extension in the cast zirconium alloy which forms a metastable supersaturated solid solution with solubility limit of around 3 wt%. The effect of yttrium and thermal treatment on the microstructure of the alloys was investigated by optical microscopy （OM） and scanning electron microscope （SEM）. The cast Zr-Y alloy shows a normal polycrys- talline structure with dispersed α-Y particles when Y content is lower than 4 wt%, while the alloy shows a eutectic structure with dendrites formation when the Y content is higher. Yttrium exhibits a strong grain refining effect on zirconium alloy and precipitates from the metastable supersaturated Zr matrix after annealing at 700 and 900 ℃.

关键词： Zirconium alloy Yttrium addition Solidsolubility extension Microstructure

Corrosion behavior of thermal-sprayed WC cermet coatings in SO_4^(2-) environment

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Rare Metals 2014年第3期33卷 318-323页

作者： yan liu xiao-Min wang sheng-bo Cen guo-qing Gou li-Jun wang Hui Chen Ming-Jing Tu Yu-Xi li School of Materials Science and engineering Sichuan University School of Materials Science and engineering Southwest Jiaotong University Zigong Tungsten Carbide Co. Ltd

A series of the electrochemical and long-term corrosion tests was carried out in a 3.5 wt% Na2SO4 solution on thermal-sprayed WC-17Co and WC-10Co-4Cr cermet coatings in order to examine the effect of composition of binder materials on the corrosion behavior. The results reveal that the overall corrosion resistance of the WC-17Co coating is inferior to that of the WC-Co-Cr coatings due to the corrosion of binder materials which induce WC particles to fall off. CoO and WO3 oxide films form on the surface of WC-17Co coating in Na2SO4 solution electrochemical corrosion process, which will protect the coating in the process of corrosion. Cr2O3 oxide film formed on the WC-10Co-4Cr coating surface has a strong hindered role to corrosion. The corrosion mechanism of WC-17Co coating in Na2SO4 solution is entire corrosion of Co matrix, while it is film-hole corrosion mechanism for WC-10Co-4Cr coating.

关键词： WC-Co WC-Co-Cr Corrosion Electrochemical

Ultrathin porous graphitic carbon nanosheets activated by alkali metal salts for high power density lithium-ion capacitors

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Rare Metals 2020年第12期39卷 1364-1373页

作者： Yu-qing Dai Guang-Chao li Xin-Hai li Hua-Jun guo Zhi-Xing wang guo-Chun yan Jie-Xi wang School of Metallurgy and Environment&College of Chemistry and Chemical engineering Central South UniversityChangsha410083China engineering Research Center of the Ministry of Education for Advanced Battery Materials School of Metallurgy and Environment&College of Chemistry and Chemical EngineeringChangsha410083China

Graphitic carbons with reasonable pore volume and appropriate graphitization degree can provide efficient li+/electrolyte-transfer channels and ameliorate the sluggish dynamic behavior of battery-type carbon negative electrode in lithium-ion capacitors(liCs).In this work,onion-like graphitic carbon materials are obtained by using carbon quantum dots as precursors after sintering,and the effects of alkali metal salts on the structure,morphology and performance of the samples are *** results show that alkali metal salts as activator can etch graphitic carbons,and the specific surface area and pore size distribution are intimately related to the description of the alkali metal ***,it also affects the graphitization degree of the *** porous graphitic carbons(SGCs)obtained by NaCl activation exhibit high specific surface area(77.14 m^(2)·g^(-1))and appropriate graphitization *** is expectable that the electrochemical performance for lithium-ions storage can be largely promoted by the smart combination of catalytic graphitization and pores-creating ***-performance liCs(S-GCs//AC liCs)are achieved with high energy density of 92 Wh·kg^(-1)and superior rate capability(66.3 Wh·kg^(-1)at10 A·g^(-1))together with the power density as high as10020.2 W·kg^(-1).

关键词： Alkali metal salts activation Porous graphitic carbons Catalytic graphitization lithium-ion capacitors

Epigenome-wide DNA methylation analysis reveals differentially methylation patterns in skeletal muscle between Chinese Chenghua and qingyu pigs

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Journal of Integrative Agriculture 2022年第6期21卷 1731-1739页

作者： wang Kai WU Ping-xian wang shu-jie JI Xiang CHEN Dong jiang An-an xiao Wei-hang jiang yan-zhi ZHU li Zeng yang-shuang XU Xu QIU xiao-tian li Ming-zhou li Xue-wei TANG guo-qing Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130P.R.China College of life Science Sichuan Agricultural UniversityYa’an 625014P.R.China Sichuan Animal Husbandry Station Chengdu 610041P.R.China National Animal Husbandry Service Beijing 100125P.R.China Chongqing Academy of Animal Science Chongqing 402460P.R.China

Chenghua(CH)pig and qingyu(QY)pig are typical Chinese native fatty *** pig is mainly distributed in Chengdu Plain,while QY pig is widely distributed throughout the mountain areas around the Sichuan *** are significant differences in their phenotypic traits,including body image,growth performance,and meat *** study compared several meat quality traits of CH and QY pigs and conducted a genome-wide DNA methylation analysis using reduced representation bisulfite sequencing(RRBS).It was observed that the pH at 45 min(pH_(45min),P=5.22e-13),lightness at 45 min(L^(*)_(45min),P=4.85e-5),and lightness at 24 h(L^(*)_(24h),P=3.57e-5)of CH pigs were higher than those of QY *** detected 10699 differentially methylated cytosines(DMCs)and 2760 differentially methylated genes(DMGs)associated with these *** analysis showed that these DMGs were mainly enriched in the AMPK signaling pathway,Type II diabetes mellitus,Insulin signaling pathway,mTOR signaling pathway,and Insulin ***,15 DMGs were associated with fat metabolism(ACACA,CAB39,CRADD,CRTC2,FASN,and GCK),muscle development(HK2,IKBKB,MTOR,PIK3CD,PPARGC1A,and RPTOR),or meat quality traits(PCK1,PRKAG2,and SLC2A4).The findings may help to understand further the epigenetic regulation mechanisms of meat quality traits in pigs and provide new basic data for the study of local pigs.

关键词： DNA methylation reduced representation bisulfite sequencing(RRBS) Chenghua pig qingyu pig