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TRAFFIC EMISSION TRANSPORTATION IN STREET CANYONS

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Journal of Hydrodynamics 2009年第1期21卷 108-117页

作者： XIE Xiao-min wang jia-song huang zhen Key Laboratory for Power Machinery and Engineering of State Education Ministry Shanghai Jiao Tong University Shanghai 200240 China

Spatial distributions of traffic-related pollutants in street canyons were investigated by field measurements and Computational Fluid Dynamics （CFD）. Two typical street canyons were selected for field monitoring, and a three-dimensional numerical model was built based on Reynolds-averaged Navier-Stokes equations equipped with the standard κ-ε turbulence models for CFD simulations. The study shows that the pollutant concentrations of vehicle emission correlate well with the traffic volume variation, wind direction and wind speed. The wind direction and speed at the roof level determine overwhellmingly the flow field and the distributions of pollutant concentrations in the street canyon. When the wind speed is equal to zero, the pollutant concentrations on the breath height of the both sides of the street canyon are almost the same. When the wind direction is perpendicular to the street, one main vortex is formed with a shape depending on the building structure on both sides of the street, the pollutant is accumulated on the leeward side, and the pollutant concentrations at the breath height on the leeward side are 2 to 3 times as those at the breath height on the windward side. If the wind direction makes some angles with the street canyon, the pollutant concentration will be higher on the leeward side because one main vortex will also be formed in the vertical section of the canyon by the perpendicular component of the wind. But pollutant concentrations decrease in the canyon because pollutants are dispersed along the axis of the street. Pollutants at different heights of the vertical section decrease with height, i.e. there are concentration gradients in the vertical section, and the pollutant concentrations on the leeward side of the upstream building are much higher than those on the windward side of the downstream building.

关键词： traffic emission street canyon field measurement CFD modeling

Si/TiO_(2) carbon fiber core encapsulated in hierarchical multiple MXene@Co-MoS_(2) shells for constructing a free-standing anode of lithium storage

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Rare Metals 2024年第9期43卷 4222-4233页

作者： Xian-ping Du Ying huang jia-ming wang zhen-he Feng Xu Sun MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shanghai Institute of Space Power-Sources Shanghai 200245China Ningbo Institute of Northwestern Polytechnical University Ningbo 315103China

Silicon-based(Si-based) materials offer more possibilities for generating new portable electronic devices due to their high specific capacities. However, their inferior electrical conductivity and volume expansion during cycling seriously limit their development. The optimum solution is to select specific materials to establish an exceptionally conductive and volume buffer structure,which can assist Si materials in developing their excellent lithium storage properties. In this study, Si particles were confined in TiO_(2)carbon fibers(TiO_(2)CFs) via electrospinning, after which they were encapsulated with MXene and Co-MoS_(2)(CMS) nanosheets to fabricate hierarchical ST-2@MXene@CMS films. TiO_(2)CF, MXene and CMS were employed to establish a coherent conductive network with one-, two-and three-dimensional electronic pathways to permit the unimpeded flow of electrons inside the electrode material. TiO_(2)CF, MXene and CMS acted precisely as multilayered buffers to ameliorate the volume change of Si particles during cycling. In addition, the CMS nanosheets were involved in lithium storage, contributing to the final electrochemical performance. Ultimately, the ST-2@MXene@CMS films served as free-standing electrodes, avoiding the impact of inactive interfaces on the electrochemical performance and fulfilling the lightweight requirement for new energy storage devices.

关键词： Si particles MXene Co-MoS_(2)nanosheets Hierarchical structure Lithium-ion batteries

Preparation and characterization of Rb-doped TiO_(2) powders for photocatalytic applications

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Rare Metals 2024年第2期43卷 555-561页

作者： Lu jia Li-Mei Yang Wei wang song-Tao huang zheng Xu National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous MetalsBeijing100088China

TiO_(2)nanoparticles doped with different concentrations of Rb were prepared by sol–gel *** crystal structures of samples were characterized by X-ray diffraction(XRD)and transmission electron microscopy(TEM).It was confirmed by the Rietveld refinement method that the as-prepared samples crystallize in anatase phase and Rb doping induces expansion and distortion of the crystal *** with the pure TiO_(2),the Rb-doped nanoparticles have smaller crystal size and better *** rate of methylene blue was used to evaluate the photocatalytic activity of Rb–TiO_(2).It indicated that doping Rb into TiO_(2)can effectively improve the photocatalytic activity of TiO_(2)and the mechanisms were discussed in *** using the sample doped with 0.20%Rb,methylene blue degraded with the fastest rate(97%within 60 min).

关键词： Rb doping TiO_(2) Photocatalysis Sol-gel

Novel intelligent reasoning system for tool wear prediction and parameter optimization in intelligent milling

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Advances in Manufacturing 2024年第1期12卷 76-93页

作者： Long-Hua Xu Chuan-zhen huang zhen wang Han-Lian Liu Shui-Quan huang Jun wang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiPeople’s Republic of China Center for Advanced Jet Engineering Technologies(CaJET) Key Laboratory of High-efficiency and Clean Mechanical Manufacture(Ministry of Education)National Experimental Teaching Demonstration Center for Mechanical Engineering(Shandong University)School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China Institute of Manufacturing Technology Guangdong University of TechnologyGuangzhou510006People’s Republic of China

Accurate intelligent reasoning systems are vital for intelligent *** this study,a new intelligent reasoning system was developed for milling processes to accurately predict tool wear and dynamically optimize machining *** developed system consists of a self-learning algorithm with an improved particle swarm optimization(IPSO)learning algorithm,prediction model determined by an improved case-based reasoning(ICBR)method,and optimization model containing an improved adaptive neural fuzzy inference system(IANFIS)and *** results showed that the IPSO algorithm exhibited the best global convergence *** ICBR method was observed to have a better performance in predicting tool wear than standard CBR *** IANFIS model,in combination with IPSO,enabled the optimization of multiple objectives,thus generating optimal milling *** paper offers a practical approach to developing accurate intelligent reasoning systems for sustainable and intelligent manufacturing.

关键词： Improved particle swarm optimization(IPSO)algorithm Improved case-based reasoning(ICBR)method Adaptive neural fuzzy inference system(ANFIS)model Tool wear prediction Intelligent manufacturing

Emergency physicians’ occupational risks in China

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World Journal of Emergency Medicine 2024年第3期15卷 232-234页

作者： Huaying jiang jia Chang Rong huang Xiayi Liang Manning song Hejing Yuan Shuo wang School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100105China Operation Room Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China School of Marxism Beijing University of Chinese MedicineBeijing 100105China Department of Infectious Diseases(Fever Clinic) Beijing Hospital of Traditional Chinese MedicineCapital Medical UniversityBeijing 100010China

With the rapid development of emergency medicine,emergency physicians are working around the clock,[1]including additional workloads due to sudden public health emergencies and *** risks for emergency physicians are s... 详细信息

关键词： physician acute occupational

Effects of Heat Transfer on Laminar-to-Turbulent Transition over a Compressor Blade Operating at Low Reynolds Number

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Journal of Thermal Science 2024年第5期33卷 1826-1838页

作者： LU Lehan wang Mingyang ZHANG Yanfeng SUN Shuang huang zhen wang Maomao Department of aviation Engineering Civil Aviation University of ChinaTianjin 300300China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Aerodynamics CARDCMianyang 621000China

To control the transition process in a laminar separation bubble(LSB)over an ultra-high load compressor blade at a Re of 1.5×10^(5),the effects of wall heat transfer were considered and numerically investigated by large eddy simulations(LES).Compared with the adiabatic wall condition,the local kinematic viscosity of airflow was reduced by wall cooling;thus the effects of turbulent dissipation on the growth of fluctuations were *** such,the transition occurred much earlier,and the size of LSB became *** the cooled surface,the spanwise vortices deformed much more rapidly and the size of hairpin vortex structures was ***,the rolling-up of 3D hairpin vortices and the ejection and sweeping process very close to the blade surface was ***,the aerodynamic losses of the compressor blade were reduced by 18.2%and 38.4%for the two cooled wall *** results demonstrated the feasibility of wall cooling in controlling the transition within an LSB and reducing the aerodynamic loss of an ultra-highly loaded compressor blade.

关键词： heat transfer compressor blade laminar-to-turbulent transition loss generation

Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： Hong huang Dan WU Yuan wang zhen wang Yu LIU College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track *** characteristics of the six hard-clustered ETCs with the highest membership coefficient are *** tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these *** landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one *** frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four *** surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying *** results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method

Application of UiO-66 and its composites for remediation and resource recovery of typical environmental contaminants:a review

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Rare Metals 2024年第6期43卷 2498-2526页

作者： Hui-Min Zhang Yun-Long wang Xin-Feng Zhu zhen-zhen huang Dan-Dan Pang Kai wang Chao-Hai wang Zhong-Xian song Shi-Qiang Yin Lin-Lin Chang Jin-Hui Zhang School Infirmary Henan University of Urban ConstructionPingdingshan 467036China Faculty of Environmental and Municipal Engineering Henan Key Laboratory of Water Pollution Control and Rehabilitation TechnologyKey Laboratory of Carbon Emission Reduction and Combined Air Pollution Control TechnologyHenan University of Urban ConstructionPingdingshan 467036China School of Resources&Environment Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic RegionHenan Polytechnic UniversityJiaozuo 454003China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationGuangzhou Higher Education Mega CentreSouth China University of TechnologyGuangzhou 510006China

UiO-66 series metal-organic framework materials(MOFs)are typical porous materials assembled by Zr^(4+) with a large mass-to-nucleus ratio and terephthalic acid ligands,which form tetrahedral and octahedral cages arranged in a periodic triangular window *** to the strong interaction between Zr and O,UiO-66 series MOFs exhibit high thermal stability,structural stability,and chemical *** article mainly reviews the applications of UiO-66 and its composites in adsorption,photocatalysis,and resource utilization,while exploring the harm of pollutants to human health and the *** the first part,the differences in adsorption and removal mechanisms of liquid organic pollutants,heavy metals,and volatile organic compounds(VOCs)are *** results show that organic pollutants are mainly removed by physical adsorption,electrostatic interactions,hydrogen bonding,andπ-πinteractions,while heavy metals are mainly removed by chemical adsorption,electrostatic interactions,reduction,and *** are mainly removed by the pore volume and pore size structure of the *** catalysis can achieve non-toxic treatment of pollutants,and this study mainly focuses on UiO-based composite materials constructed by strategies such as semiconductor composites,ion doping,and metal/dye *** the second part,the synergistic effect between the components of UiO-based composite materials promotes the oriented and rapid separation and transfer of earriers at the material interface,thereby promoting the generation of active species such as h^(+),·O_(2)^(-) and·OH,and achieving rapid degradation of pollutants and detoxification of heavy *** the third part,heterojunctions can realize the resource utilization of pollutants in water and air,producing energy-type substances such as hydrogen and methanol while solving environmental *** addition,this article also summarizes the harm of common typical pollutants to the environment

关键词： UiO Adsorption Photocatalysis Environmental pollution Resource recovery

Molecular crowding electrolytes for stabilizing Zn metal anode in rechargeable aqueous batteries

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Chinese Chemical Letters 2024年第7期35卷 445-451页

作者： Li Lin song-Lin Tian zhen-Yu Hu Yu Zhang Li-Min Chang jia-Jun wang Wan-Qiang Liu Qing-Shuang wang Fang wang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China School of Life Science and Technology Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education Jilin Normal UniversityChangchun 130103China Zhongshan Institute of Changchun University of Science and Technology Zhongshan 528437China

A solid electrolyte interphase(SEI)with a robust mechanical property and a high ionic conductivity is imperative for high-performance zinc metal ***,it is difficult to form such a SEI directly from an *** this work,a molecular crowding effect is based on the introduction of Zn(OTF)_(2)and Zn(ClO_(4))_(2)to 2 mol/L ZnSO_(4)*** and experiments indicate that the Zn(OTF)_(2)and Zn(ClO_(4))_(2)not only create a molecularly crowded electrolyte environment to promote the interaction of Zn^(2+)and OTF^(-),but also participate in the reduction to construct a robust and high ionic-conductive SEI,thus promoting metal zinc deposition to the(002)crystal *** this molecular crowding electrolyte,a high current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn as the anode for over 1000 *** in a temperature environment of-10℃,a current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn for over 200 ***//Bi_(2)S_(3)/VS4@C cells achieve a CE rate of up to 99.81%over 1000 ***,the utilization of a molecular crowding electrolyte is deemed a highly effective approach to fabricating a sophisticated SEI for a zinc anode.

关键词： Zinc ion batteries Anode Electrolyte Solid electrolyte interphase Molecular crowding effect