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Journal of Shanghai Jiaotong university(Science) 2024年第4期29卷 625-639页

作者： xing Youjing gao Jinfeng LIU Xiaoping WU Ping School of Information Science and Engineering Zhejiang Sci-Tech UniversityHangzhou310018China Department of Systems and Computer Engineering Carleton UniversityOttawaK1S 5B6Canada

To address fixed-time consensus problems of a class of leader-follower second-order nonlinear multi-agent systems with uncertain external disturbances,the event-triggered fixed-time consensus protocol is ***,the virtual velocity is designed based on the backstepping control method to achieve the system consensus and the bound on convergence time only depending on the system ***,an event-triggered mechanism is presented to solve the problem of frequent communication between agents,and triggered condition based on state information is given for each *** is available to save communication resources,and the Zeno behaviors are ***,the delay and switching topologies of the system are also ***,the system stabilization is analyzed by Lyapunov stability ***,simulation results demonstrate the validity of the presented method.

关键词： event-triggered mechanism fixed-time consensus multi-agent systems switching topologies

Structural Evolution of Ultra-High Molecular Weight Polyethylene Low-Entangled Films with Reserved Shish Crystals During Hot Stretching

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Chinese Journal of Polymer Science 2024年第8期42卷 1227-1242页

作者： Jia-Wei gao Li Chen Ye-Shun Zhong Chao-Wei xing Yi-Guo Li Zong-Bao Wang School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

Shish crystals are crucial to achieving high performance low-dimensional ultra-high molecular weight polyethylene(UHMWPE)***,high stretch and shear flow fields are necessary for the formation of shish *** this study,UHMWPE gel films with reserved shish crystals were prepared by gel molding,the structural evolution and properties of UHMWPE films stretched at temperatu res of 100,110,120and 130℃were investigated by in situ small-angle X-ray scattering(SAXS)/ultra-small-angle X-ray scattering(USAXS)/wide-angle X-ray diffraction(WAXD)measu rements as well as scanning electron microscopy(SEM)and differential scanning calorimetry(DSC)*** findings showed that the reserved shish crystals can facilitate the formation and structural evolution of shish-kebab crystals during the hot ***,the reserved shish crystals promote the structu ral evolution of UHMWPE films to a greater extent when stretched at 120 and 130℃,compared to 100 and 110℃,resulting in higher crystallinity,orientation,thermal properties,breaking strength and Young's *** pared to UHMWPE high-entangled films with reserved shish crystals prepared by compression molding,UHMWPE low-entangled films with reserved shish crystals prepared by gel molding are more effective in inducing the formation and evolution of shish-kebab crystals during the hot stretching,resulting in increased breaking strength and Young's modulus.

关键词： UHMWPE low-entangled films Reserved shish crystals Structural evolution Hot stretching

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Effect of lanthanum on inclusions in non-oriented electrical steel slabs

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Journal of Iron and Steel Research International 2024年第7期31卷 1680-1691页

作者： Qiang Ren zhi-yuan Hu Yun-xia Liu Wei-cheng Zhang Zi-qi gao Li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Research and Development Department Shougang Zhixin Qian'an Electromagnetic Material Co.Ltd.Qian'an 064400HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The effect of lanthanum on the characteristics of inclusions in the slab of non-oriented electrical steels was investigated through industrial trials and thermodynamic *** number,size,and chemical composition of inclusions in the surface,one-quarter of thickness and the center of slabs with and without lanthanum addition were statistically analyzed using an automatic inclusion analysis *** the lanthanum-free slab,inclusions were predominately ***_(2)O_(3),MgO,and AlN as well as a small number of Al_(2)O_(3)-MgO-CaO and *** number densities of oxide inclusions and AlN decreased from the surface to the center of the slab,which was ascribed to the difference in cooling intensity during the continuous *** the steel with lanthanum addition,inclusions were modified into LaAlO_(3) and La_(2)O_(2)S and gradually transformed into dual-phase MgO-La_(2)S3 with an increasing distance from the slab surface due to the reaction between the lanthanum-containing inclusion and the steel *** uneven distribution of oxide inclusions along the thickness of the slab was eliminated in the lanthanum-bearing slab because the dissolved oxygen was remarkably decreased by ***-bearing inclusions were more likely to agglomerate AlN by inducing the heterogeneous nucleation of AlN on their surface,while small-size ***_(2)O_(3) inclusions hardly showed a coarsening effect on the size of AlN.

关键词： Lanthanum-Inclusion Non-oriented electrical steel Aluminum nitride Heterogenous nucleation

Key role of electron accessibility at the noble metal-free catalytic interface in hydrogen evolution reaction

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Nano Research 2024年第4期17卷 2538-2545页

作者： Dongchen Han Nanxing gao Yuyi Chu Zhaoping Shi Ying Wang Junjie Ge Meiling Xiao Changpeng Liu Wei xing State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources Changchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The reactant concentration at the catalytic interface holds the key to the activity of electrocatalytic hydrogen evolution reaction(HER),mainly referring to the capacity of adsorbing hydrogen and electron *** hydrogen adsorption free energy(ΔGH)as a reactivity descriptor,the volcano curve based on Sabatier principle is established to evaluate the hydrogen evolution activity of ***,the role of electron as reactant received insufficient attention,especially for noble metal-free compound catalysts with poor conductivity,leading to cognitive gap between electronic conductivity and apparent catalytic *** we successfully construct a series of catalyst models with gradient conductivities by regulating molybdenum disulfide(MoS_(2))electronic bandgap via a simple solvothermal *** demonstrate that the conductivity of catalysts greatly affects the overall catalytic *** further elucidate the key role of intrinsic conductivity of catalyst towards water electrolysis,mainly concentrating on the electron transport from electrode to catalyst,the electron accumulation process at the catalyst layer,and the charge transfer progress from catalyst to *** and experimental evidence demonstrates that,with the enhancement in electron accessibility at the catalytic interface,the dominant parameter governing overall HER activity gradually converts from electron accessibility to combination of electron accessibility and hydrogen adsorbing *** results provide the insight from various perspective for developing noble metal-free catalysts in electrocatalysis beyond HER.

关键词： conductivity molybdenum disulfide catalytic interface electron accessibility hydrogen evolution charge transfer.

Efficient recovery of tungsten from scheelite concentrates using a sulfur-phosphorus mixed acid leaching system

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Tungsten 2024年第4期6卷 821-832页

作者： Jiang-Tao Li Li-Li gao Zhong-Wei Zhao Xu-Heng Liu xing-Yu Chen School of Metallurgy and Environment Central South University Key Laboratory of Hunan Province for Metallurgy and Material Processing of Rare Metals

In recent years,a new process for leaching scheelite concentrates with sulfur-phosphorus mixed acid has been successfully *** process suffers from the elimination of the retarding effect of calcium sulfate,the selective extraction of tungsten from the H3PW12O40-H2SO4-H3PO4mixture solution,and the removal of introduced ***,in this paper,we investigated the inhibition measures of a calcium sulfate-blocking membrane,the selective extraction of tungsten by ion exchange,and the removal of phosphorus by the magnesium ammonium salt *** results showed that the addition of calcium sulfate whisker seeds and a higher H3PO4concentration inhibited spontaneous diffuse nucleation,promoted crystal growth,and avoided the formation of a dense blocking *** 98 wt.% of the scheelite concentrate was digested by *** selective adsorption of PW12O403-was realized using D301 resin,and the extraction efficiency of tungsten exceeded 99.9%.After desorption with ammonia water,PW12O403-was depolymerized into WO42-and PO43-.99.9 wt.% of phosphorus was removed in the form of MgNH4PO4by the magnesium ammonium salt method,and the residual phosphorus concentration in the solution was lower than 10 mg·*** purification,the highest-grade ammonium paratungstate product was prepared by evaporative crystallization.

关键词： Calcium sulfate Ion exchange Scheelite concentrates Sulfur-phosphorus mixed acid Tungsten

Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1809-1815页

作者： zhi-Gang Chen gao-Qin Liu Wei-Ming Liu Pei-Rong Lu Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Jiangsu Clinical Immunology Institute the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential ***:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A *** cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular ***-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of *** expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of *** may serve as a potential target for anti-angiogenic therapy.

关键词： vialinin A vascular endothelial growth factor human retinal endothelial cells cell viability

Exact Convergence Rate of the Local Limit Theorem for a Branching Random Walk in Zd with a Random Environment in Time

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Chinese Annals of Mathematics,Series B 2024年第5期45卷 805-822页

作者： Jian-xin LIU zhi-qiang gao School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems (Ministry of Education) School of Mathematical Sciences Beijing Normal University

Abstract Consider a branching random walk with a random environment in time in the d-dimensional integer *** branching mechanism is governed by a supercritical branching process,and the particles perform a lazy random walk with an independent,non-identical increment *** A?Zd,let Z_n（A） be the number of offsprings of generation n located in *** exact convergence rate of the local limit theorem for the counting measure Zn（·） is *** partially extends the previous results for a simple branching random walk derived by gao （2017,*** Appl.）.

关键词： 60F05 60G50 60J10 60J80 Branching random walk Exact convergence rate Local limit theorems Random environment

Interfacial modification using the cross-linkable tannic acid for highly-efficient perovskite solar cells with excellent stability

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Journal of Energy Chemistry 2024年第4期91卷 236-244页

作者： xing gao Lirong Rong Fei Wu Yen-Hung Lin Ye Zeng Junhong Tan Rongxing He Cheng Zhong Linna Zhu Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy School of Materials&EnergySouthwest UniversityChongqing 400715China Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Department of ChemistryWuhan UniversityWuhan 430072HubeiChina Key Laboratory of Luminescence Analysis and Molecular Sensing Ministry of EducationSchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloon 999077Hong KongChina State Key Laboratory of Advanced Displays and Optoelectronics Technologies The Hong Kong University of Science and TechnologyClear Water BayKowloon 999077Hong KongChina

Although the performance of perovskite solar cells(PSCs)has been dramatically increased in recent years,stability is still the main obstacle preventing the PSCs from being *** device instability can be caused by a variety of reasons,including ions diffusion,surface and grain boundary defects,*** this work,the cross-linkable tannic acid(TA)is introduced to modify perovskite film through post-treatment *** numerous organic functional groups(–OH and C=O)in TA can interact with the uncoordinated Pb^(2+)and I^(-)ions in perovskite,thus passivating defects and inhibiting ions *** addition,the formed TA network can absorb a small amount of the residual moisture inside the device to protect the perovskite ***,TA modification regulates the energy level of perovskite,and reduces interfacial charge ***,following TA treatment,the device efficiency is increased significantly from 21.31%to 23.11%,with a decreased hysteresis ***,the treated device shows excellent air,thermal,and operational *** light of this,the readily available,inexpensive TA has the potential to operate as a multipurpose interfacial modifier to increase device efficiency while also enhancing device stability.

关键词： Tannic acid Defect passivation lons diffusion Hydrophilic Stability Perovskite solar cells

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Photocatalytic applications and modification methods of two-dimensional nanomaterials:a review

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Tungsten 2024年第1期6卷 77-113页

作者： Fan Yang Ping Hu Fan Yang xing-Jiang Hua Bo Chen Lili gao Kuai-She Wang School of Metallurgy Engineering Xi’an University of Architecture and TechnologyXi’an 710055China National and Local Joint Engineering Research Center for Functional Materials Processing Xi’an University of Architecture and TechnologyXi’an 710055China

Due to its unique electronic structure and special size effect,two-dimensional(2D)nanomaterials have shown great potential far beyond bulk materials in the field of *** to deeply explore the photocatalytic mechanism of 2D nanomaterials and design more efficient 2D semiconductor photocatalysts are research *** review provides a comprehensive introduction to typical 2D nanomaterials and discusses their current application status in the field of *** effects of material properties such as band structure,morphology,crystal face structure,crystal structure and surface defects on the photocatalytic process are *** main modification methods are highlighted,including doping,noble metal deposition,heterojunction,thickness adjustment,defect engineering,and dye sensitization in 2D material ***,the future development of 2D nanomaterials is *** is hoped that this paper can provide systematic and useful information for researchers engaged in the field of photocatalysis.

关键词： Photocatalysis Two-dimensional Nanomaterials Bandgap Modification strategy

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Chemoselective Transfer Hydrogenation of Nitroarenes with Ammonia Borane Catalyzed by Copper N-Heterocyclic Carbene Complexes

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Chinese Journal of Chemistry 2024年第15期42卷 1721-1726页

作者： Hui Zhou Hongmei Jiao xing Lu Yuanyuan gao zhiqiang Ren Haojie Ma Yuqi Zhang Bo Han Laboratory of New Energy&New Function Materials Shaanxi Key Laboratory of Chemical Reaction EngineeringCollege of Chemistry and Chemical EngineeringYan'an UniversityYan'anShaanxi 716000China

Herein,we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading(1 mo%)of copper N-heterocyclic carbene complexes as the catalyst and ammonia borane as the source of hydrogen.A wide range of nitroarenes,featuring diverse functional groups,were selectively transformed into their corresponding primary aromatic amines with high *** process can be readily scaled up and exhibits compatibility with various sensitive functional groups,including halogen,trifluoromethyl,aminomethyl,alkenyl,cyano,ester,amide,and ***,this catalytic methodology finds application in the synthesis of essential drug *** investigations suggest that the in-situ-generated Cu-H species may serve as active intermediates,with reduction pathways involving species such as azobenzene,1,2-diphenylhydrazine,nitrosobenzene,and N-phenylhydroxylamine.

关键词： Homogeneous catalysis Hydrogenation N-Heterocyclic carbene complexes Nitroarenes Ammonia borane