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Journal of Energy Chemistry 2023年第5期80卷 373-380,I0009页

作者： Jinliang Song yayun Pang Chenglei Xiao Huizhen Liu Buxing Han School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006GuangdongChina Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of ColloidInterface and Chemical ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Catalytic hydrogenolysis of aromatic ether bonds is a highly promising strategy for upgrading lignin into small-molecule chemicals,which relies on developing innovative heterogeneous catalysts with high ***,we designed porous zirconium phosphate nanosheet-supported Ru nanocatalysts(Ru/ZrPsheet)as the heterogeneous catalyst by a process combining ball milling and molten-salt(KNO_(3)).Very interestingly,the fabricated Ru/ZrPsheetshowed good catalytic performance on the transfer hydrogenolysis of various types of aromatic ether bonds contained in lignin,i.e.,4-O-5,a-O-4,β-O-4,and aryl-O-CH3,over a low Ru usage(<0.5 mol%)without using any acidic/basic *** investigations indicated that the properties of Ru and the support were *** excellent activity of Ru/ZZrPsheetoriginated from the strong acidity and basicity of ZrPsheetand the higher electron density of metallic Ru0as well as the nanosheet structure of ZrPsheet.

关键词： Valorization of lignin Aromatic ether bonds Transfer hydrogenolysis synergistic cooperation Zirconium phosphate nanosheets

DPHK： real-time distributed predicted data collecting based on activity pattern knowledge mined from trajectories in smart environments

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Frontiers of Computer Science 2016年第6期10卷 1000-1011页

作者： Chengliang WANG yayun PENG Debraj DE Wen-Zhan SONG Key Laboratory of Dependable Service Computing in Cyber Physical Society Chongqing University Chongqing 400044 China College of Computer Science Chongqing University Chongqing 400044 China Department of Computer Science Georgia State University Atlanta GK 30303 USA

In this paper, we have proposed and designed DPHK （data prediction based on HMM according to activity pattern knowledge mined from trajectories）, a real-time distributed predicted data collection system to solve the congestion and data loss caused by too many connections to sink node in indoor smart environment scenarios （like Smart Home, Smart Wireless Healthcare and so on）. DPHK predicts and sends predicted data at one time instead of sending the triggered data of these sensor nodes which people is going to pass in several times. Firstly, our system learns the knowl- edge of transition probability among sensor nodes from the historical binary motion data through data mining. Secondly, it stores the corresponding knowledge in each sensor node based on a special storage mechanism. Thirdly, each sensor node applies HMM （hidden Markov model） algorithm to pre- dict the sensor node locations people will arrive at according to the received message. At last, these sensor nodes send their triggered data and the predicted data to the sink node. The significances of DPHK are as follows：（a） the procedure of DPHK is distributed; （b） it effectively reduces the connection between sensor nodes and sink node. The time complexities of the proposed algorithms are analyzed and the performance is evaluated by some designed experiments in a smart environment.

关键词： trajectory prediction sensor data mining wireless sensor networks smart environments hidden Markov model

A LINEARLY-IMPLICIT STRUCTURE-PRESERVING EXPONENTIAL TIME DIFFERENCING SCHEME FOR HAMILTONIAN PDEs

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Journal of Computational Mathematics 2024年第4期42卷 1063-1079页

作者： yayun Fu Dongdong Hu Wenjun Cai Yushun Wang Henan Joint International Research Laboratory of High Performance Computation for Complex Systems School of ScienceXuchang UniversityXuchang 461000China School of Mathematics and Statistics Jiangxi Normal UniversityJiangxiNanchang 330022China Jiangsu Key Laboratory for NSLSCS Jiangsu Collaborative Innovation Center of Biomedial Functional MaterialsSchool of Mathematical SciencesNanjing Normal UniversityNanjing 210023China

In the paper,we propose a novel linearly implicit structure-preserving algorithm,which is derived by combing the invariant energy quadratization approach with the exponential time differencing method,to construct efficient and accurate time discretization scheme for a large class of Hamiltonian partial differential equations(PDEs).The proposed scheme is a linear system,and can be solved more efficient than the original energy-preserving ex-ponential integrator scheme which usually needs nonlinear *** experiments are performed to verify the conservation,efficiency and good performance at relatively large time step in long time computations.

关键词： Structure-preserving algorithm Hamiltonian PDE Energy quadratization method Exponential time differencing

Oxidation-induced phase separation of carbon-supported CuAu nanoparticles for electrochemical reduction of CO_(2)

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Nano Research 2023年第2期16卷 2119-2125页

作者： yayun Guan Yatian Liu Qingye Ren Zejian Dong Langli Luo Institute of Molecular Plus Department of ChemistryTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Alloy nanostructures have been extensively exploited in both thermal and electrochemical catalysis due to their beneficial“synergetic effects”and being *** of the alloy nanostructures including phases,interfaces,and chemical composition are prerequisites for utilizing them as efficient ***,we use carbon-supported CuAu nanoparticles as a model catalyst to demonstrate the phase-separation induced variation of electrochemical performance for the CO_(2)reduction *** by thermal oxidation,the CuOx phase gradually separates from the original CuAu nanoparticles,and different carbon supports,i.e.,graphene *** nanotube lead to a reversed trend in the selectivity towards CO *** detailed structural and chemical analysis,we find the extent of phase separation holds the key to this variation and could be used as an effective method to tune the electrochemical properties of the alloy phase.

关键词： CuAu CO_(2)reduction reaction electrochemical phase separation atomic scale

Elastic buckling analysis and optimization of thin-walled bamboo-like pipe beam subjected to pure bending

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Chinese Journal of Aeronautics 2024年第3期37卷 133-152页

作者： yayun YU Dongli MA Liang ZHANG Xiaopeng YANG Hao GUAN School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

In this paper,a stiffening design imitating the bamboo node is proposed for weight reduction of the long composite pipe beam subjected to bending *** distribution of bamboo nodes can efficiently suppress the ovalization of the section,thus significantly improving the bending resistance of the *** on this principle,ring stiffeners are proposed to be fixed to the pipe beam,making the long beam equivalent to the combination of a series of short pipes that suffered less section ovalization.A database of the optimal laminate orientations for different normalized lengths is obtained through optimizations,where the discreteness of the ply count is *** on this database,weight optimizations are conducted,and the optimal designs of beams with and without stiffeners are obtained and *** comparison results show that the proposed bamboo-like stiffened beam not only regains a near-linear load–displacement relationship,but also reduces the weight by up to 16%under the same buckling *** addition,it is found that for the pipe beams with radius-to-thickness ratios of more than 18,increasing the radius leads to a decrease in elastic buckling resistance when the weight remains a constant,which is opposite to the design for strength and *** model and database developed in this paper can provide a reference for weight reduction design and weight estimation for composite pipe beams.

关键词： Composite beam Buckling Thin-walled structure Unmanned aerial vehicles Bamboo

Oscillation quenching and physical explanation on freeplay-based aeroelastic airfoil in transonic viscous flow

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Chinese Journal of Aeronautics 2023年第10期36卷 124-136页

作者： yayun SHI Shun HE Gaowei CUI Gang CHEN Yan LIU State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Beijing Institute of Structure and Environment Engineering Beijing 100076China Shenyang Aircraft Design Institute Shenyang 110036China

Limit Cycle Oscillation(LCO)quenching of a supercritical airfoil(NLR 7301)considering freeplay is investigated in transonic viscous *** Fluid Dynamics(CFD)based on Navier-Stokes equations is implemented to calculate transonic aerodynamic forces.A loosely coupled scheme with steady CFD and an efficient graphic method are developed to obtain the aerodynamic *** quenching phenomenon is observed from the nonlinear dynamic aeroelastic response obtained by using time marching *** the airspeed increases,LCO appears then quenches,forming the first LCO *** the quenching region,LCO occurs again and sustains until the divergence of the response,forming the second LCO *** quenching of LCOs was addressed physically based on the aerodynamic preload and the linear flutter ***“island”of stable region is observed in the flutter boundary,*** flutter speed versus the mean Angle of Attack(AoA).The LCO quenches when the aerodynamic preload crosses this stable region with the increasing of *** LCO quenching of this model in transonic flow is essentially induced by destabilizing effect from aerodynamic preload,since the flutter speed is sensitive to AoA due to aerodynamic nonlinearity.

关键词： Freeplay Nonlinear aeroelasticity Supercritical airfoil Transonic flutter Unsteady flow

Biological and bioinspired materials: Structure leading to functional and mechanical performance

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Bioactive Materials 2020年第4期5卷 745-757页

作者： yayun Wang Steven ENaleway Bin Wang Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen518055PR China Department of Mechanical Engineering University of UtahSalt Lake CityUT84112USA

Nature has achieved materials with properties and mechanisms that go far beyond the current know-how of the engineering-materials *** remarkable efficiency of biological materials,such as their exceptional properties that rely on weak constituents,high performance per unit mass,and diverse functionalities in addition to mechanical properties,has been mostly attributed to their hierarchical *** strategies for bioinspired materials include formulating the fundamental understanding of biological materials that act as inspiration,correlating this fundamental understanding to engineering needs/problems,and fabricating hierarchically structured materials with enhanced properties *** vast,existing literature on biological and bioinspired materials can be discussed in terms of functional and mechanical *** essential representative properties and materials,the development of bioinspired materials utilizes the design strategies from biological systems to innovatively augment material performance for various practical applications,such as marine,aerospace,medical,and civil *** the current challenges,bioinspired materials have become an important part in promoting innovations and breakthroughs in the modern materials industry.

关键词： Biological and bioinspired materials Hierarchical structure Design strategy Functional and mechanical performance

Butyl ether as Co-diluent in medium-concentrated electrolyte for Li-S battery

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Journal of Energy Chemistry 2023年第10期85卷 343-347,I0010页

作者： Xirui Kong yayun Zheng Lang He Du Wang Yan Zhao The Institute of Technological Sciences Wuhan UniversityWuhan 430000HubeiChina

1. Introduction The Lithium-sulfur battery(LSB) shows promise as a highdensity energy source, with a theoretical energy density of approximately 2600 W h kg^(-1)[1]. However, practical application of the LSB has been hindered by the “shuttle effect” and Li anode corrosion [2,3]. Highly concentrated electrolytes(HCEs) have been proposed as a solution, as they can inhibit the dissolution of lithium polysulfide and promote homogeneous lithium deposition [4].

关键词： Lithium-sulfur battery Diluted electrolyte Butyl ether Co-diluent

Remarkable enhancement of gas selectivity on organosilica hybrid membranes using urea-modulated metal-organic framework nanoparticles

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 83-92页

作者： yayun Zhao Dechuan Zhao Chunlong Kong Yichao Lin Xuezhen Wang Liang Chen Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Collaboration Innovation Center for Tissue Repair Material Engineering Technology China West Normal UniversityNanchong 637009China

Metal-organic framework/organosilica hybrid membranes on tubular ceramic substrates have shown great potential for the implementation of membrane technology in practical gas separation projects due to their higher permeance compared to commercial ***,the selectivities of the reported membranes are ***,we have incorporated urea-modulated metal-organic frameworks into organosilica membranes to greatly enhance its separation *** urea-modulated metal-organic frameworks exhibit less-defined edges of crystallographic facets and high defect *** can be well-dispersed in the organosilica layer,which substantially suppresses the interfacial defects between metal-organic frameworks and organosilica,which is beneficial for improving the selectivity of membranes for gas *** results have shown that the enhanced ideal selectivity of H_(2)/CH_(4) was 165 and that of CO_(2)/CH_(4) was 43,with H_(2) permeance of about 1.25×10^(−6) mol·m^(−2)·s^(−1)·Pa^(−1) and CO_(2) permeance of 3.27×10^(−7) mol·m^(−2)·s^(−1)·Pa^(−1) at 0.2 MPa and 25℃.In conclusion,the high level of hybrid membranes can be used to separate H_(2)(or CO_(2))from the binary gas mixture H_(2)/CH_(4)(or CO_(2)/CH_(4)),which is important for gas separation in practical ***,the simple and feasible modulation of metal-organic framework is a promising strategy to tune different metal-organic frameworks for membranes according to the actual demands.

关键词： ZIF-8 nanocrystals urea organosilica hybrid membrane enhanced separation performance

Silibinin ameliorates hepatic lipid accumulation and oxidative stress in mice with non-alcoholic steatohepatitis by regulating CFLAR-JNK pathway

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Acta Pharmaceutica Sinica B 2019年第4期9卷 745-757页

作者： yayun Liu Wei Xu Ting Zhai Jiaojiao You Yong Chen Hubei Province Key Laboratory of Biotechnology of Chinese Traditional Medicine National & Local Joint Engineering Research Center of High-throughput Drug Screening Technology Hubei University

Non-alcoholic steatohepatitis(NASH) is a chronic metabolic syndrome and the CFLAR-JNK pathway can reverse the process of NASH. Although silibinin is used for the treatment of NASH in clinical, its effect on CFLAR-JNK pathway in NASH remains unclear. This study aimed to investigate the effect of silibinin on CFLAR-JNK pathway in NASH models both in vivo and in vitro. The in vivo study was performed using male C57 BL/6 mice fed with methionine– choline-deficient diet and simultaneously treated with silibinin for 6 weeks. The in vitro study was performed by using mouse NCTC-1469 cells which were respectively pretreated with oleic acid plus palmitic acid, and adenovirus-down Cflar for 24 h,then treated with silibinin for 24 h. After the drug treatment, the key indicators involved in CFLAR-JNK pathway including hepatic injury, lipid metabolism and oxidative stress were determined. Silibininsignificantly activated CFLAR and inhibited the phosphorylation of JNK, up-regulated the mRNA expression of Pparα, Fabp5, Cpt1α, Acox, Scd-1, Gpat and Mttp, reduced the activities of serum ALT and AST and the contents of hepatic TG, TC and MDA, increased the expression of NRF2 and the activities of CAT, GSH-Px and HO-1, and decreased the activities and expression of CYP2 E1 and CYP4 A in *** effects were confirmed by the in vitro experiments. Silibinin prevented NASH by regulating CFLAR-JNK pathway, and thereby on one hand promoting the β-oxidation and efflux of fatty acids in liver to relieve lipid accumulation, and on the other hand inducing antioxidase activity(CAT, GSH-Px and HO-1) and inhibiting pro-oxidase activity(CYP2 E1 and CYP4 A) to relieve oxidative stress.

关键词： Silibinin NASH CFLAR Lipid accumulation Oxidation stress