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National Science Review 2017年第3期4卷 500-509页

作者： ling wang Shuxian Wu NCNST

INTRODUCTION Nanoscience and technology,as an emerging science and technology frontier,is continuously deepening and transforming our understanding of the material *** better prepare for rapid evolutions of nanoscienc... 详细信息

关键词： for SWNTs NCNST The National Center for Nanoscience and Technology,China an international innovation engine for nano research of CAS in from that Nano is

A numerical study on tread wear and fatigue damage of railway wheels subjected to anti-slip control

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Friction 2023年第8期11卷 1470-1492页

作者： Yunfan YANG Liang ling Jiacheng wang Wanming ZHAI State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China

Tread wear and rolling contact fatigue (RCF) damage propagated on railway wheels are the two extremely important focal points as they can tremendously deteriorate wheel/rail interactions and hunting stability and destroy wheel surface materials, and subsequently, cut down the lifetime of the wheels. The on-board anti-slip controllers are of essence aiming to hold back the striking slipping of the powered wheelsets under low-adhesion wheel/rail conditions. This paper intends to investigate the impact of anti-slip control on wheel tread wear and fatigue damage under diverse wheel/rail friction conditions. To this end, a prediction model for wheel wear and fatigue damage evolution on account of a comprehensive vehicle–track interaction model is extended, where the wheel/rail non-Hertzian contact algorithm is used. Furthermore, the effect of frictional wear on the fatigue damage at wheel surface is considered. The simulation results indicate that the wheel/rail contact is full-slip under the low-adhesion conditions with braking effort. The wear amount under the low-adhesion conditions is observably higher than that under the dry condition. It is further suggested that the wheel tread is prone to suffering more serious wear and fatigue damage issues with a higher anti-slip control threshold compared to that with a lower one.

关键词： anti-slip control wheel/rail non-Hertzian contact adhesion condition wheel tread wear fatigue damage

Coupling functional anodes with natural air-diffused cathodes enables highly efficient hydrogen peroxide electrosynthesis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第4期24卷 377-386页

作者： Chen ling Aiping LIANG Chaolin LI Wenhui wang School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhenShenzhen 518055China State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090 China

Electrosynthesis of hydrogen peroxide(H_(2)O_(2))is a decentralized production method with excellent application *** anodes with cathodes can achieve highly efficient electrosynthesis of hydrogen *** this study,we prepared an anode for H_(2)O_(2) electrosynthesis via the two-electron water oxidation reaction(2e-WOR)by modifying carbon fiber paper with self-assembling *** addition,a natural air-diffused cathode loaded with polytetrafluoroethylene/carbon black using carbon cloth as substrate was prepared to combine with the modified anode to produce H_(2)O_(2) *** total current efficiency of the anode and cathode reached 152.9%,and the H_(2)O_(2) production rate was as high as 38μmol/min at 2.8 V *** hydrogen electrodes(RHE)in a Nafion 117 membrane-separated *** work reported a novel carbon-based 2e-WOR catalyst and laid a theoretical foundation for the simultaneous electrosynthesis of H_(2)O_(2) with an anode and cathode.

关键词： Two-electron water oxidation Two-electron oxygen reduction Self-assembled membrane Hydrogen peroxide Electrosynthesis

Enhanced methane recovery and exoelectrogen-methanogen evolution from low-strength wastewater in an up-flow biofilm reactor with conductive granular graphite fillers

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 131-140页

作者： Zechong Guo Lei Gao ling wang Wenzong Liu Aijie wang State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology (SKLUWRE HIT) Harbin 150001 China Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences. Beijing 100085 China＊

Methane production from low-strength wastewater （LSWW） is generally difficult because of the low metabolism rate of methanogens. Here, an up-flow biofilm reactor equipped with conductive granular graphite （GG） as fillers was developed to enhance direct interspecies electron transfer （DIET） between syntrophie electroactive bacteria and methanogens to stimulate methanogcnesis process. Compared to quartz sand fillers, using condnctive fillers significantly enhanced methane production and accelerated the start-up stage *** reactor. At HRT of 6 h, the average methane production rate and methane yield of reactor with GG were 0.106 m3/（m3.d） and 74.5 L/kg COD, which increased by 34.3 times and 22.4 times respectively compared with the reactor with common quartz sand fillers. The microbial cornmunity analysis revealed that methanogens structure was significantly altered and the archaea that are involved in DIET （such as Methanohacterium） were enriched in GG fillet- The beneficial effects ot conductive fillers on methane production implied a practical strategy tbr efficient methane recovery from LSWW.

关键词： Low-strength wastewater Methane production Conductive filler Microbial community structure

Massive lithospheric delamination in southeastern Tibet facilitating continental extrusion

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National Science Review 2022年第4期9卷 23-32页

作者： Jikun Feng Huajian Yao ling Chen Weitao wang Laboratory of Seismology and Physics of Earth's Interior School of Earth and Space SciencesUniversity of Science and Technology of China CAS Center for Excellence in Comparative Planetology University of Science and Technology of China Mengcheng National Geophysical Observatory University of Science and Technology of China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences CAS Center for Excellence in Deep Earth Science Institute of Geophysics China Earthquake Administration

Significant left-lateral movement along the Ailao Shan-Red River fault accommodated a substantial amount of the late Eocene to early Miocene India-Asia ***,the activation of this critical strike-slip fault remains poorly ***,we show key seismic evidence for the occurrence of massive lithospheric delamination in southeastern *** novel observation of reflected body waves(e.g.P410P and P660P) retrieved from ambient noise interferometry sheds new light on the massive foundered lithosphere currently near the bottom of the mantle transition zone beneath southeastern *** integrating the novel seismic and pre-existing geochemical observations,we highlight a linkage between massive lithospheric delamination shortly after the onset of hard collision and activation of continental extrusion along the Ailao Shan-Re d River *** information provides critical insight into the early-stage evolution of the India-Asia collision in southeastern Tibet,which has significant implications for continental collision and its intracontinental response.

关键词： ambient noise interferometry reflected body waves lithospheric delamination India-Asia collision Indochina extrusion

Constrained Multi-Objective Optimization With Deep Reinforcement Learning Assisted Operator Selection

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 919-931页

作者： Fei Ming Wenyin Gong ling wang Yaochu Jin the School of Computer Science China University of GeosciencesWuhan 430074China the Department of Automation Tsinghua UniversityBeijing 100084China the Faculty of Technology Bielefeld UniversityNorth Rhine-Westphalia33619 BielefeldGermany

Solving constrained multi-objective optimization problems with evolutionary algorithms has attracted considerable *** constrained multi-objective optimization evolutionary algorithms(CMOEAs)have been developed with the use of different algorithmic strategies,evolutionary operators,and constraint-handling *** performance of CMOEAs may be heavily dependent on the operators used,however,it is usually difficult to select suitable operators for the problem at ***,improving operator selection is promising and necessary for *** work proposes an online operator selection framework assisted by Deep Reinforcement *** dynamics of the population,including convergence,diversity,and feasibility,are regarded as the state;the candidate operators are considered as actions;and the improvement of the population state is treated as the *** using a Q-network to learn a policy to estimate the Q-values of all actions,the proposed approach can adaptively select an operator that maximizes the improvement of the population according to the current state and thereby improve the algorithmic *** framework is embedded into four popular CMOEAs and assessed on 42 benchmark *** experimental results reveal that the proposed Deep Reinforcement Learning-assisted operator selection significantly improves the performance of these CMOEAs and the resulting algorithm obtains better versatility compared to nine state-of-the-art CMOEAs.

关键词： Constrained multi-objective optimization deep Qlearning deep reinforcement learning(DRL) evolutionary algorithms evolutionary operator selection

Preparation and crystalline phase of a TiO_2 porous film by anodic oxidation

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Rare Metals 2005年第4期24卷 330-335页

作者： wang Wei TAO Jie ZHANG Weiwei TAO Haijun wang ling College of Material Science and Technology Nanjing University of Aeronautics ＆ Astronautics Nanjing 210016 China

Anatase titanium dioxide is an active photocatalyst, but it is difficult to immobilize on the substrate. A crystalline TiO2 porous film was prepared directly on the surface of pure titanium by anodic oxidation in this work. Constant voltage and constant current anodic oxidation were adopted with sulphuric acid used as the electrolyte, pure titanium as the anode and copper as the cathode. The morphology and structure of the porous film on the substrate were analyzed with the aid of Field Emission Scanning Electron Microscopy （FESEM） and X-ray Diffraction （XRD）. The effects of the parameters of anodic oxidation （such as voltage, the concentration of sulphuric acid, anodization time and current density） on the aperture and the crystalline phase of the TiO2 porous film were systematically investigated. The results indicate that the increase of current density facilitates the augment of the aperture and the generation of anatase and mille. In addition, the forming mechanism of anatase and mille TiO2 porous films was discussed.

关键词： metal materials titanium oxide porous film anodic oxidation anatase rutile

A Solution Supporting Secure Transmission of Big Data

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Tsinghua Science and Technology 2023年第5期28卷 838-848页

作者： Haonan ling Yan Gao Huibin wang Ming Chen Institute of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China China Electronic Systems Engineering Corporation Beijing 100840China College of Computer and Information Engineering Chuzhou UniversityChuzhou 239000

Traditional Internet protocol networks cannot provide the service of selecting a secure path to transmit various types of data with specific security ***,to solve the“secure path transmission”problem,this paper first proposes a search-transmit model for secure network path transmission,i.e.,to find a multi-attribute optimized path that meets the specific security requirements in the search phase,and then transmit the packets along the optimized path in the transmission ***,we propose a solution to the search-transmit *** idea of the solution is to use the particle swarm optimization algorithm to search for a secure path that meets the multi-attribute requirements and then set the source route on the router to control the packet ***,a prototype system based on network function virtualization is developed to evaluate the feasibility and performance of the proposed *** results show that the proposed solution outperforms existing algorithms in terms of performance.

关键词： network secure path search-transmit model multi-attribute path optimization segment routing network function virtualization

Colour modulation and enhancement of upconversion emissions in K_(2)NaScF_(6):Yb/Ln(Ln=Er,Ho,Tm) nanocrystals

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Journal of Rare Earths 2021年第12期39卷 1477-1483,I0001页

作者： Yangbo wang Huaiyong Li Hui Ma ling Huang School of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059China Institute of Advanced Materials Nanjing Tech UniversityNanjing 211816China

Effective colour modulation of upconversion emissions in lanthanide-doped nanomaterials becomes even more important for fundamental and applied ***,on the one hand,by raising the content of doped Yb^(3+)from 10 mol%to 50 mol%,a significant increase of the red/green emission ratio from 4.0 to 68.2 is observed in K_(2)NaScF_(6):Yb/Er *** yellow to red colour change is attributed to the increased cross relaxation between Er^(3+)and Yb^(3+)caused by the increased Yb^(3+)amount,^(4) S_(3/2)(Er^(3+))^(+2) F7/2(Yb^(3+))→4 I13/2(Er^(3+))^(+2) F5/2(Yb^(3+)).On the other hand,the upconversion green and red emission of K_(2)NaScF_(6):Yb/Er(20/2 mol%)nanocrystals are intensified 10.6 and 8.8 folds,respectively,after an active shell(K_(2)NaScF_(6):Yb)is epitaxially grown,which are more effective than the7.4-and 6.4-fold enhancement from an inert shell(K_(2)NaScF_(6))***,the shell thickness from2.85 to 9.5 nm through controlling the molar ratio of shell-precursor to core from 1:2 to 3:1 can be easily *** study will provide more opportunities for the application of K_(2)NaScF_(6):Yb/Ln nanoparticles in varied fields such as theranostics,photovoltaics,and photocatalysis.

关键词： Upconversion Emission modulation Core-shell K_(2)NaScF_(6) Rare earths

Numerical simulation on flow of ice slurry in horizontal straight tube

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Frontiers in Energy 2021年第1期15卷 201-207页

作者： Shengchun LIU Ming SONG ling HAO Pengxiao wang Tianjin Key Laboratory of Refrigeration Technology Tianjin University of CommerceTianjin 300134China

Numerical simulation on flow of ice slurry in horizontal straight tubes was conducted in this paper to improve its transportation characteristics and *** paper determined the influence of the diameter and length of tubes,the ice packing factors(IPF)and the flow velocity of ice slurry on pressure loss by using numerical simulation,based on two-phase flow and the granular dynamic ***,it was found that the deviation between the simulation results and experimental data could be reduced from 20%to 5%by adjusting the viscosity which was reflected by *** confirmed the reliability of the simulation ***,two mathematical correlations between viscosity and flow velocity were developed *** could also be concluded that future rheological model of ice slurry should be considered in three sections clarified by the flow velocity,which determined the fundamental difference from single-phase fluid.

关键词： ice slurry horizontal tubes numerical simulation pressure drop viscosity model