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Journal of Thermal science 2024年第5期33卷 1607-1617页

作者： DU shen he Yaling LI Dong LIU Zhanbin LI Mengjie National Innovation Platform(Center)for Industry-Education Integration of Energy storage Technology Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an Jiaotong UniversityXi’an710049China

Direct pore-scale and volume-averaging numerical simulations are two methods for investigating the performance of porous volumetric solar *** clarify the difference in the prediction of heat transfer processes,a direct comparison between these two methods was conducted at both steady state and transient *** numerical models were established based on X-ray computed tomography scans and a local thermal non-equilibrium model,*** empirical parameters,which are indispensable to the volume-averaging simulation,were determined by Monte Carlo ray tracing and direct pore-scale numerical *** predicted outlet air temperature of the receiver by the volume-averaging simulation method corresponded satisfactorily to that in the direct pore-scale *** largest discrepancies were observed when the receiver's working temperature was elevated,with differences of 5.5%and 3.68%for the steady state and transient state simulations,***,the volume-averaging method is incapable of capturing the local temperature information of the air and porous *** underestimates the inlet temperature of the receiver,leading to an overestimation of the receiver's thermal efficiency,with the largest difference being 6.51%.The comparison results show that the volume-averaging model is a good approximation to the pore-scale model when the empirical parameters are carefully selected.

关键词： porous media volumetric solar receiver pore-scale method volume-averaging method thermal performance

Evaluation of arsenic pollution in field-contaminated soil at the soil’s actual pH

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Journal of Environmental sciences 2024年第10期144卷 137-147页

作者： Tiancong Gao Haixia Tian Huimin Niu Mallavarapu Megharaj Wenxiang he College of Natural Resources and Environment Northwest A&F UniversityKey Laboratory of Plant Nutrition and Agro-environment in Northwest ChinaMinistry of AgricultureYanglingShaanxi 712100China Global Centre for Environmental Remediation College of EngineeringScience and EnvironmentUniversity of NewcastleCallaghanNSW 2308Australia

The pollution and ecological risks posed by arsenic(As)entering the soil are the major environmental challenges faced by human *** phosphatase can serve as a useful indicator for assessing As contamination under specific soil pH ***,the study of phosphatase kinetics in long-term field As-contaminated soil remains unclear,presenting a significant obstacle to the monitoring and evaluation of As pollution and *** purpose of this study was to determine phosphatase activity and explore enzyme kinetics in soils subjected to long-term field As *** revealed that the soil phosphatase activity varied among the tested soil samples,depending on the concentrations of *** relationship between total As,As fractions and phosphatase activity was found to be significant through negative exponential function *** parameters,including maximum reaction velocity(Vmax),Michaelis constant(Km)and catalytic efficiency(V_(max)/K_(m)),ranged from 3.14×10^(−2)–53.88×10^(−2) mmol/(L·hr),0.61–7.92 mmol/L,and 0.46×10^(−2)–11.20×10^(−2) hr−1,*** and Vmax/Km of phosphatase decreased with increasing As pollution,while Km was less ***,Vmax/Km showed a significant negative correlationwith all As fractions and total *** ecological doses(ED10)for the complete inhibition and partial inhibition models ranged from0.22–70.33 mg/kg and 0.001–55.27 mg/kg,respectively,indicating that V_(max)/K_(m) can be used as an index for assessing As pollution in field-contaminated *** study demonstrated that the phosphatase kinetics parameters in the soil’s pH system were better indicators than the optimal pH for evaluating the field ecotoxicity of As.

关键词： Arsenic pollution Ecological risk soil phosphatase Enzyme kinetics Catalytic efficiency(V_(max)/K_(m))

Tungsten oxide/nitrogen-doped carbon nanotubes composite catalysts for enhanced redox kinetics in lithium-sulfur batteries

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Chinese Journal of Chemical Engineering 2024年第3期67卷 58-67页

作者： Deqing he Zihao Xie Qian Yang Wei Wang Chao su school of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China state Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-s)batteries are a significant obstacle to their widespread adoption as energy storage ***,recent studies have shown that tungsten oxide(WO_(3))can facilitate the conversion kinetics of polysulfides in Li-s ***,we fabricated host materials for sulfur using nitrogen-doped carbon nanotubes(N-CNTs)and WO_(3).We used low-cost components and simple procedures to overcome the poor electrical conductivity that is a disadvantage of metal *** composites of WO_(3) and N-CNTs(WO_(3)/N-CNTs)create a stable framework structure,fast ion diffusion channels,and a 3D electron transport network during electrochemical reaction *** a result,the WO_(3)/N-CNT-Li2s6 cathode demonstrates high initial capacity(1162 mA·h·g^(-1) at 0.5℃),excellent rate performance(618 mA·h·g^(-1) at 5.5℃),and a low capacity decay rate(0.093%up to 600 cycles at 2℃).This work presents a novel approach for preparing tungsten oxide/carbon composite catalysts that facilitate the redox kinetics of polysulfide conversion.

关键词： Li-s batteries Composites Ion diffusion channels 3D electron transport network Redox kinetics

Metal-to-insulator transitions in 3d-band correlated oxides containing Fe compositions

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 48-59页

作者： Yiping Yu Yuchen Cui Jiangang he Wei Mao Jikun Chen Key Laboratory of Advanced Materials and Devices for Post-Moore Chips Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China school of Materials science and Engineering University of Science and Technology BeijingBeijing 100083China Institute of Industrial science The University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

Metal-to-insulator transitions (MITs),which are achieved in 3d-band correlated transitional metal oxides,trigger abrupt variations in electrical,optical,and/or magnetic properties beyond those of conventional *** such material families,iron(Fe:3d^(6)4s^(2))-containing oxides pique interest owing to their widely tunable MIT properties,which are associated with the various valence states of *** potential electronic applications also show promise,given the large abundance of Fe on *** MIT properties triggered by critical temperature (TMIT) were reported for ReFe_(2)O_(4)(Fe^(2.5+)),ReBaFe_(2)O_(5)(Fe^(2.5+)),Fe_(3)O_(4)(Fe^(2.67+)),Re_(1/3)sr_(2/3)FeO_(3)(Fe^(3.67+)),Re Cu_(3)Fe_(4)O_(12)(Fe^(3.75+)),and Ca_(1-x)sr_(x)FeO_(3)(Fe^(4+))(where Re represents rare-earth elements).The common feature of MITs of these Fe-containing oxides is that they are usually accompanied by charge ordering transitions or disproportionation associated with the valence states of ***,we review the material family of Fe-containing MIT oxides,their MIT functionalities,and their respective *** the perspective of potentially correlated electronic applications,the tunability of the TMITand its resultant resistive change in Fe-containing oxides are summarized and further compared with those of other materials exhibiting MIT *** particular,we highlight the abrupt MIT and wide tunability of TMITof Fe-containing quadruple perovskites,such as Re ***,their effective material synthesis still needs to be further explored to cater to potential applications.

关键词： metal-to-insulator transitions Fe-containing oxides charge ordering charge disproportionation

Highly Flexible Graphene-Film-Based Rectenna for Wireless Energy Harvesting

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Energy & Environmental Materials 2024年第2期7卷 320-325页

作者： Jingwei Zhang Yuchao Wang Rongguo song Zongkui Kou Daping he Hubei Engineering Research Center of RF-Microwave Technology and Application School of ScienceWuhan University of TechnologyWuhan 430070China sanya science and Education Innovation Park of Wuhan University of Technology Sanya 572000China state Key Laboratory of Advanced Technology for Materials synthesis and Processing Wuhan University of TechnologyWuhan 430070China

herein,we report the design,fabrication,and performance of two wireless energy harvesting devices based on highly flexible graphene macroscopic films(FGMFs).We first demonstrate that benefiting from the high conductivity of up to 1×10^(6)s m^(-1)and good resistive stability of FGMFs even under extensive bending,the FGMFs-based rectifying circuit(GRC)exhibits good flexibility and RF-to-DC efficiency of 53%at 2.1 ***,we further expand the application of FGMFs to a flexible wideband monopole rectenna and a 2.45 GHz wearable rectenna for harvesting wireless *** wideband rectenna at various bending conditions produces a maximum conversion efficiency of 52%,46%,and 44%at the 5th Generation(5G)2.1 GHz,Industrial Long-Term Evolution(LTE)2.3 GHz,and scientific Medical(IsM)2.45 GHz,respectively.A 2.45 GHz GRC is optimized and integrated with an AMC-backed wearable *** proposed 2.45 GHz wearable rectenna shows a maximum conversion efficiency of 55.7%.All the results indicate that the highly flexible graphene-film-based rectennas have great potential as a wireless power supplier for smart Internet of Things(loT)applications.

关键词： flexible rectennas highly flexible graphene-based films wireless energy harvesting

Identification of the optimal doping position of hetero-atoms in chalcogen-doped Fe-N-C catalysts for oxygen reduction reaction

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Particuology 2024年第6期89卷 99-108页

作者： Weihao Liu Huanhuan he Qingtao Liu Xin Wan Jianglan shui school of Materials science and Engineering Beihang UniversityBeijing100191China school of space and Environment Beihang UniversityBeijing102206China Tianmushan Laboratory Hangzhou310023China

The excellent oxygen reduction reaction(ORR)activity of Fe–N–C catalysts in acidic media makes them potential for low-cost proton exchange membrane fuel *** recent years,it has been shown that heteroatoms(B,O,s,P,Cl,F,etc.)can be used as electron-withdrawing groups to modulate the planar structure and electron distribution of the Fe–Nx active sites to achieve simultaneous improvement of catalytic activity and ***,the optimal location of the heteroatoms remains ***,taking chalcogen heteroatoms(s and se)as an example,we control the doping positions and investigate their effect on the ORR performance of the Fe–N–C *** first coordination shell of the iron single atom is identified as the optimal doping *** optimized catalysts Fe–N_(3)se_(1)/NC and Fe–N_(3)se_(1)/NC demonstrate improved activity and stability in both half cells and fuel *** work provides insights into the enhancement mechanism of heteroatom doping in single-atom catalysts.

关键词： Oxygen reduction reaction Fe-N-C catalysts hetero-atom doping Doping position Enhancement mechanism

Numerical simulation of transient characteristics in a bulb turbine during the load rejection process

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Journal of Hydrodynamics 2024年第1期36卷 170-183页

作者： Yue Lu Yu-quan Zhang Zhong-wei he Yuan Zheng College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China Huadong Engineering Corporation Ltd. Hangzhou311122China

To evaluate the safety of the bulb tubular turbine,the dynamic hydraulic characteristics of a hydropower station system during the load rejection process are studied through numerical simulations and a prototype *** the developed model,a dynamic grid technology(DGT)controls the closure of the guide vane and the blade,whilst the moment balance equation and the user-defined function(UDF)provide the runner’s rotation *** 3-D transient simulation method can well predict the rotation speed and mass flow curves in the state of load *** simulation outcomes of the system performance are basically consistent with the measurement data of the *** observed,the runner is subjected to the reversely increased torque and axial force,the system is in a braking phase,and the maximum speed peaks at 144.6%of the rated ***,the internal flow of the runner is greatly affected by the closure of the guide vane,and the draft tube forms an eccentric spiral vortex *** breaks downstream,aggravating the instability of the draft ***,the transient characteristics span for the first five seconds,demonstrating the importance of establishing an efficient governing *** obtained results are useful for designing the turbine’s flow channel with a double regulating function and comprehending the turbine’s transient characteristics.

关键词： Bulb tubular turbine load rejection numerical simulation dynamic grid prototype test

Accurate shortwave Radiation simulation with a Two-Layer Aerosol Model in Xinjiang Region

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Journal of Meteorological Research 2024年第1期38卷 69-87页

作者： Guan HUANG Yonghang CheN Qiong LIU Pengtao WANG Qianshan he Qing he shuai LI Weiling sHAO Ting FAN school of Tourism&Research Institute of Human Geography Xi’an International Studies UniversityXi’an 710128 Center for silk Road and Eurasian Civilization studies Xi’an International Studies UniversityXi’an 710128 College of Environmental science and Engineering Donghua UniversityShanghai 201620 shanghai Meteorological service Shanghai 200030 shanghai Key Laboratory of Meteorology and health Shanghai 200030 Taklimakan Desert Meteorology Field Experiment station of China Meteorological Administration Institute of Desert MeteorologyUrumqi 830002 Xinjiang Climate Centre Xinjiang Meteorological ServiceUrumqi 830002

To harness the rich solar energy resources in Xinjiang Region of Northwest China,this study tries to address the issue of lack of downward surface shortwave radiation(DssR)observations and the need to improve the accuracy of satellite retrieval and numerical simulation of DssR under varied sky and meteorological conditions.(1)A two-layer aerosol model specific to Xinjiang was developed to capture the vertical distributions of aerosols based on multiple data sources including lidar,GPs sounding,ground meteorological observations,and profiles from the ECMWF reanalysis version 5(ERA5)*** results show that the ERA5/PBLH(planetary boundary layer height)and ERA5/ALH(aerosol layer height)could be used to establish the two-layer aerosol model and characterize the vertical distribution of aerosols in Xinjiang Region.(2)Using the santa Barbara Discrete Atmospheric Radiative Transfer(sBDART)model,a localized inverse model of clear-sky DssR was *** parameter adjustment and using the optimal combination of input parameters for DssR simulation together with the two-layer aerosol model,the model-simulated DssR(DssRsBD)under clear-sky conditions improved significantly compared to the initial results,with all fitting indices greatly improved.(3)In addition,the study demonstrated that the impact of the two-layer aerosol model on DssR was more pronounced under dust conditions than clear-sky conditions.(4)Using the localized clear-sky DssR inversion model and its required parameters,simulations were also conducted to capture the spatiotemporal distribution of DssR under clear-sky conditions in Xinjiang from 2017 to *** annual average DssR_(sBD)under clear-sky conditions in Xinjiang during 2017–2019 was 606.78 W m^(-2),while DssR from CEREs(DssR_(CER))under the same conditions was generally higher(703.95 W m^(-2)).(5)It is found that satellite remote sensing products experienced data loss in high-altitude snow areas,where numerical simulation technology could ser

关键词： downward surface shortwave radiation(DssR) aerosol vertical distribution Clouds and the Earth’s Radiant Energy system(CEREs) santa Barbara Discrete Atmospheric Radiative Transfer(sBDART) Xinjiang

Perception of fundamental science to boost lithium metal anodes toward practical application

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Green Energy & Environment 2024年第3期9卷 454-472页

作者： Jinkun Wang Li Wang Hong Xu Li sheng Xiangming he Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

As a key material for lithium metal batteries(LMBs),lithium metal is one of the most promising anode materials to break the bottleneck of battery energy density and a commonly used active material for reference *** lithium anodes are regarded as the holy grail of lithium batteries,decades of exploration have not led to the successful commercialization of LMBs,due mainly to the challenges related to the inherent properties of lithium *** pave the way for further investigation,herein,a comprehensive review focusing on the fundamental science of lithium are ***,the natures of lithium atoms and their isotopes,lithium clusters and lithium crystals are revisited,especially their structural and energetic ***,the electrochemical properties of lithium metal are *** important concepts and scientific questions,including the electronic structure of lithium,influence of high pressure and low temperature on the properties of lithium,factors influencing lithium deposition,generation of lithium dendrites,and electrode potential of lithium in different electrolytes,are explained and analyzed in *** to improve the performance of lithium anodes and thoughtfulness about the electrode potential in lithium battery research are proposed.

关键词： Lithium Cluster Crystal Physicochemical property Fundamental science

Clifford Deformations of Koszul Frobenius Algebras and Noncommutative Quadrics

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Algebra Colloquium 2024年第1期31卷 63-82页

作者： Jiwei he Yu Ye Department of Mathematics Hangzhou Normal UniversityHangzhou 311121China school of Mathematical sciences University of Science and Technology of China Hefei 230026China

A Clifford deformation of a Koszul Frobenius algebra E is a finite dimensional Z_(2)-graded algebra E(θ),which corresponds to a noncommutative quadric hypersurface E^(!)/(z)for some central regular element z∈E_(2)^(!).It turns out that the bounded derived category D^(b)(gr_(Z_(2))E(θ))is equivalent to the stable category of the maximal Cohen-Macaulay modules over E^(!)/(z)provided that E!is *** a consequence,E^(!)/(z)is a noncommutative isolated singularity if and only if the corresponding Clifford deformation E(θ)is a semisimple Z_(2)-graded *** preceding equivalence of triangulated categories also indicates that Clifford deformations of trivial extensions of a Koszul Frobenius algebra are related to Knörrer's periodicity theorem for quadric *** an application,we recover Knörrer's periodicity theorem without using matrix factorizations.

关键词： Koszul Frobenius algebra Clifford deformation noncommutative quadric hypersurface maximal Cohen-Macaulay module