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Frontiers of Earth Science 2024年第1期18卷 83-97页

作者： Yijie wen Jianguo zhang Shu TAO Chenyu CAI School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas(Ministry of Land Resources) China University of Geosciences(Beijing)Beijing 100083China School of Foreign Languages China University of Geosciences(Beijing)Beijing 100083China

The deformation structure of soft sediments has always been a research hotspot,which is of great significance for analyzing the tectonic and sedimentary evolution background of a basin,as well as the physical properties of *** studies have reported that a large number of soft sediment deformation structures are developed in the western part of Liaohe *** this study,through core observation and thin section identification,various types of deformation structures are identified in the core samples which are collected from the upper Es4 in the Leijia region,western sag of Liaohe depression,such as liquefied dikes,liquefied breccia,convoluted laminae,annular bedding,synsedimentary faults,vein structures,*** on the characteristics of core structure,single well profile and continuous well profile,combined with the regional background,this study clarifies that the deformation structure of soft sediments in the study area is mainly caused by seismic *** is found that the permeability and porosity of deformation layers in the study area are higher than those of the undeformation layers,which proves that the deformation structure of soft sediments has a good effect on improving the physical properties of reservoirs.

关键词： soft sediment deformation structure Liaohe depression organic-rich fine-grained soft sediments hydrocarbon significance

Cobalt doping amount determines dominant reactive species in peroxymonosulfate activation via porous carbon catalysts co-doped by cobalt and nitrogen

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Journal of Environmental Sciences 2024年第4期138卷 212-226页

作者： Xiang Li Limeng wu Aiqin zhang Shaohua wu Yan Lin Chunping Yang Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle Nanchang Hangkong UniversityNanchang 330063China Academy of Environmental and Resource Sciences School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000China College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China

Switching the reaction routes in peroxymonosulfate(PMS)-based advanced oxidation processes have attracted much attention but remain ***,a series of Co-N/C catalysts with different compositions and structures were prepared by using bimetallic zeolitic imidazolate frameworks based on ZIF-8 and ZIF-67(x Zn/Co-ZIFs).Results show that Co doping amount could mediate the transformation of the activation pathway of PMS over CoN/*** Co doping amount was less than 10%,the constructed x Co-N/C/PMS system(x≤10%)was singlet oxygen-dominated reaction;however further increasing Co doping amount would lead to the generation and coexistence of sulfate radicals and high-valent cobalt,besides singlet ***,the nitrogen-coordinated Co(Co-NX)sites could serve as main catalytically active sites to generate singlet *** excess Co doping amount caused the formation of Co nanoparticles from which leached Co ions were responsible for the generation of sulfate radicals and high-valent *** to undoped N/C,Co doping could significantly enhance the catalytic *** 0.5%Co-N/C could achieve the optimum degradation(0.488 min^(-1))and mineralization abilities(78.4%)of sulfamethoxazole among the investigated Co-N/C catalysts,which was superior to most of previously reported *** addition,the application prospects of the two systems in different environmental scenarios(pH,inorganic anions and natural organic matter)were assessed and showed different degradation *** study provides a strategy to regulate the reactive species in PMS-based advanced oxidation process.

关键词： Peroxymonosulfate Sulfate radical Singlet oxygen Cobalt Zeolitic imidazolate framework Advanced oxidation process

Flotation separation of scheelite from calcite using luteolin as a novel depressant

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 462-472页

作者： Xiaokang Li Ying zhang Haiyang He Yu wu Danyu wu Zhenhao Guan Faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Clean Utilization of Complex Non-Ferrous Metal Resources Kunming University of Science and TechnologyKunming 650093China

This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)*** suitability of LUT as a calcite depressant is confirmed through micro-flotation *** pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two ***,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on *** capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is ***-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions *** directly illustrates the distinct adsorption densities of LUT on the two miner-al ***,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.

关键词： scheelite calcite luteolin flotation depressant separation

Traveling wave solutions in a nonlocal dispersal SIR epidemic model with nonlocal time-delay and general nonlinear incidences

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International Journal of Biomathematics 2024年第5期17卷 101-132页

作者： Weixin wu wenbui zhang College of Mathematics and Systerm Science Xinjiang University Urumnqi 830017 P.R.China

This paper investigates a nonlocal dispersal epidemic model under the multiple nonlocal distributed delays and nonlinear incidence ***,the minimal wave speed c*and the basic reproduction number Ro are defined,which determine the existence of traveling wave ***,with the help of the upper and lower solutions,Schauder's fixed point theorem,and limiting techniques,the traveling waves satisfying some asymptotic boundary conditions are ***,when Ro>1,for every speed c>c^(*) there exists a traveling wave solution satisfying the boundary conditions,and there is no such traveling wave solution for any 01 or c>0 when R_(0)<***,we analyze the effects of nonlocal time delay on the minimum wave speed.

关键词： Nonlocal distributed delay general nonlinear incidence upper and lower solutions traveling waves

Solvent-free carbon sphere nanofluids towards intelligent lubrication regulation

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Friction 2024年第1期12卷 95-109页

作者： Sheng zhang wen LI Xiaoliang MA Xiaoqiang FAN Minhao ZHU Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

By simply switching the electrical circuit installed on steel/steel contact,the tribological behaviors of nanofluids(NFs)can be regulated in real time,thereby achieving the desired performance of friction reduction and wear ***,solvent-free carbon spherical nanofluids(C-NFs)were successfully prepared for intelligent lubrication regulation.C-NFs with excellent lubrication performance can immediately reduce the coefficient of friction(COF)despite applying a weak electric potential(1.5 V).Moreover,polyethylene glycol 400(PEG400)containing 5.0 wt%C-NFs remained responsive to electrical stimulation under the intermittent voltage application with an average coefficient of friction(ACOF)reduction of 20.8%over *** intelligent lubrication regulation of C-NFs under an external electric field(EEF)mainly depends on the orderly arranged double-electric adsorption film of ion canopy-adsorbed carbon spheres(CSs).The intermittent electrical application can continuously reinforce the adsorption film and its durability for real-time controlling the sliding ***-stimulation-responsive intelligent lubricants provide a new technical support for realizing intelligent stepless control of devices.

关键词： solvent-free carbon spherical nanofluids(C-NFs) intelligent lubrication regulation lubrication performance adsorption film

Recent advances in ocular lubrication

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Friction 2024年第9期12卷 1929-1954页

作者： Jianhua zhang Yunjuan SU Jian wu Hongdong WANG School of Mechatronic Engineering and Automation and Key Laboratory of Advanced Display and System Application Ministry of EducationShanghai UniversityShanghai 200444China

The ocular lubrication,where the eyelid constantly slides on the curved corneal surface,is considered as one of primary lubrication systems in *** reliable lubrication conditions,sensitive ocular tissues remain intact from fatigue damage during spontaneous blink *** tear film,evenly filled between cornea and conjunctiva,is a biological fluid with dynamic adjustment ability,which provides superior lubrication with the friction coefficient of below ***,the lubrication failure may result in a variety of uncomfortable symptoms such as inflammatory reactions,tissue damage and neurological ***,it is essential to clarify the fundamental mechanism of ocular lubrication,which helps to alleviate and even recover from various ocular *** review firstly demonstrates that the ocular components,containing lipids and mucins,contribute to maintaining the lubrication stability of tear ***,the ocular lubrication state in various physiological environments and the physical effect on tear film dynamics are further *** typical applications,the therapeutic agents of dry eye syndrome and contact lens with superior lubrication effects are introduced and their lubrication mechanisms are ***,this review summarizes a series of the latest research inspired by ocular ***,this work will provide a valuable guidance on the theoretical research and extensive applications in the field of biological lubrication.

关键词： bio-tribology ocular lubrication tear film dry eye syndrome tear film dynamics

Topology optimization of AISI 4140 steel with surface texture filled by multi-solid lubricants for enhancing tribological properties

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Friction 2024年第9期12卷 2033-2051页

作者： Qipeng HUANG Chaohua wu Xiaoliang SHI Kaipeng zhang School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China

Wind power gears will be excessively worn due to lubrication failure during ***,the tribological properties of rubbing pairs are improved by filling solid lubricants into surface *** texture design,three types of topological textures(Circle(C),Hexagon(H),and Circle/Hexagon(CH))were obtained by cell topology optimization,and then three cases with 20%,30%,and 40%density were designed for each ***,SnAgCu and TiC were deposited in texture of AISI 4140 steel(AS)to obtain 9 kinds of self-lubricating *** them,AS with 30%CH density(AS-CH30)exhibits excellent mechanical and tribological *** with AS-C and AS-H,the maximum equivalent stress of AS-CH was decreased by 10.86%and 5.37%,*** coefficient and wear rate of AS-CH30 were 79.68%and 78%lower than those of *** excellent tribological performances of AS-CH30 can be attributed to the synergistic effect of topological surface and solid *** surface can not only reduce fluctuation of equivalent stress,but also promote the stored lubricants to be easily transferred at the contact interface to form a 200 nm lubricating film containing solid lubricants(mainly),oxides and wear debris.

关键词： topological texture nano-TiC self-lubricating solid lubrication

Black Phosphorus for Photonic Integrated Circuits

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Research 2024年第2期2023卷 339-353页

作者： Mingxin zhang Lele Yang Xiaoxuan wu Junjia Wang National Research Center for Optical Sensors/communications Integrated Networks School of Electronic Science and EngineeringSoutheast University2 SipailouNanjing 210096China

Black phosphorus gives several advantages and complementarities over other two-dimensional *** has drawn extensive interest owing to its relatively high carrier mobility,wide tunable bandgap,and in-plane anisotropy in recent *** manuscript briefly reviews the structure and physical properties of black phosphorus and targets on black phosphorus for photonic integrated *** of the applications are discussed including photodetection,optical modulation,light emission,and polarization *** recent progresses,associated challenges,and future potentials are covered.

关键词： polarization tunable phosphorus

Lattice Boltzmann simulation study of anode degradation in solid oxide fuel cells during the initial aging process

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 405-411页

作者： Shixue Liu Zhijing Liu Shuxing zhang Hao wu Hydrogen Energy Industrial Technology Innovation Center China Nuclear Power Technology Research InstituteShenzhen 518031China Shenzhen Engineering Research Center for Hydrogen Safety Shenzhen 518031China

For present solid oxide fuel cells(SOFCs),rapid performance degradation is observed in the initial aging process,and the dis-cussion of the degradation mechanism necessitates quantitative ***,focused ion beam-scanning electron microscopy was em-ployed to characterize and reconstruct the ceramic microstructures of SOFC *** lattice Boltzmann method(LBM)simulation of multiphysical and electrochemical processes in the reconstructed models was *** samples collected from industrial-size cells were characterized,including a reduced reference cell and a cell with an initial aging *** parameters of the reconstructed microstructures revealed a significant decrease in the active triple-phase boundary and Ni connectivity in the aged cell compared with the reference *** LBM simulation revealed that activity degradation is dominant compared with microstructural degradation during the initial aging process,and the electrochemical reactions spread to the support layer in the aged *** microstructural and activity de-gradations are attributed to Ni migration and coarsening.

关键词： solid oxide fuel cell anode degradation focused ion beam-scanning electron microscopy lattice Boltzmann method

Controlling underestimation bias in reinforcement learning via minmax operation

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Chinese Journal of Aeronautics 2024年第7期37卷 406-417页

作者： Fanghui HUANG Yixin HE Yu zhang Xinyang DENG wen JIANG School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China College of Information Science and Engineering Jiaxing UniversityJiaxing 314001China

Obtaining the accurate value estimation and reducing the estimation bias are the key issues in reinforcement ***,current methods that address the overestimation problem tend to introduce underestimation,which face a challenge of precise decision-making in many *** address this issue,we conduct a theoretical analysis of the underestimation bias and propose the minmax operation,which allow for flexible control of the estimation ***,we select the maximum value of each action from multiple parallel state-action networks to create a new state-action value ***,a minimum value is selected to obtain more accurate value ***,based on the minmax operation,we propose two novel algorithms by combining Deep Q-Network(DQN)and Double DQN(DDQN),named minmax-DQN and ***,we conduct theoretical analyses of the estimation bias and variance caused by our proposed minmax operation,which show that this operation significantly improves both underestimation and overestimation biases and leads to the unbiased ***,the variance is also reduced,which is helpful to improve the network training ***,we conduct numerous comparative experiments in various environments,which empirically demonstrate the superiority of our method.

关键词： Reinforcement learning Minmax operation Estimation bias Underestimation bias Variance