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Thorium isotopes ((228)Th,(230)Th,(232)Th) and applications in reconstructing the Yangtze and Yellow River floods

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International Journal of Sediment Research 2013年第4期28卷 588-595页

作者： Wei-feng YANG Min CHEN Xin-xing ZHANG Zhi-gang GUO Guang-xue LI Qiang MA Jun-hong YANG yi-pu huang State Key Laboratory of Marine Environmental Science Xiamen University Department of Environmental Science and Engineering Fudan University College of Marine Geo-Science Ocean University of China

In the past decades,the Hoods of the Yangtze and Yellow River introduced unexpected changes of the ecological community and sedimentary dynamics in the Fast China Sea(KCS).To reconstruct the flood events in the ECS,228Th,230Th and232Th have been examined in a sediment *** specific activities of three thorium isotopes have good positive relations with line fractions(<63 urn),indicating that Th activity concentrations heavily depend upon the sediment grain *** size-normalized activities of228Th,230Th and232Th showed significant *** between the higher Th activities and historical Hoods of the Yangtze and Yellow River demonstrated that size-normalized Th recorded the two rivers’ flood *** activity ratios of thorium isotopes,i.e.230Th/232Th and228Th/232Th,also showed similar patterns to the historical river *** three periods(1740s,[840—1860s and1930- 1960s),characterized by frequent Hoods,the thorium activity ratios were fairly low and close to the Yangtze and Yellow River estuary sediments,coinciding with the less oceanic228Th and230Th contributions during the flooding ***,these results support the size-normalized Th activity and thorium ratios as proxies of the river floods in coastal seas.

关键词： Thorium Yellow River Yangtze River Flood East China Sea

Research progress in performance improvement strategies and sulfur conversion mechanisms of Li-S batteries based on Fe series nanomaterials

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Nano Research 2024年第9期17卷 8045-8067页

作者： Ziyang huang Zhenghua Wang Lei Zhou Jun pu Key Laboratory of Functional Molecular Solids(Ministry of Education) College of Chemistry and Materials ScienceAnhui Provincial Engineering Laboratory for New-Energy Vehicle Battery Energy-Storage MaterialsAnhui Normal UniversityWuhu 241000China School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China Department of Electrical Engineering Eindhoven University of TechnologyEindhoven MB 5600The Netherlands

Lithium-sulfur(Li-S)batteries hold the potential to revolutionize energy storage due to the high theoretical capacity and energy ***,the commercialization process is seriously hindered by the rapid capacity decay and low utilization of sulfur,caused by the inevitable slow dynamics and the“shuttle effect”.The incorporation of metal-based electrocatalysts into sulfur cathodes shows promise in promoting the conversion of lithium polysulfides(LiPSs),reducing the“shuttle effect”,and enhancing cell kinetics and cycle *** these,Fe-based materials,characterized by environmental friendliness,low cost,abundant reserves,and high activity,are extensively used in sulfur cathode *** article reviews the advancements of Fe-based materials in enhancing Li-S batteries in recent *** from single/multi-component Fe-based metal compounds and single/bimetallic atoms,the influence of different Fe coordination environments on the conversion mechanism of LiPSs is *** is hoped that this review and the proposed prospects can further stimulate the development and application of the Fe element in Li-S batteries in the future.

关键词： Li-S batteries Fe-based nanomaterials shuttle effect reaction kinetics

Bibliometric analysis and systematic review of electrochemical methods for environmental remediation

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Journal of Environmental Sciences 2024年第10期144卷 113-136页

作者： Wenbin huang Shibin Liu Tao Zhang Hao Wu Shengyan pu College of Earth Sciences Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology) Chengdu 610059China College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China Key Laboratory of Biodiversity Formation Mechanism and Comprehensive Utilization of the Qinghai-Tibet Plateau in Qinghai Province Qinghai Normal UniversityXining 810008China Scientific Research Academy of Guangxi Environmental Protection Nanning 530022China

Electrochemical methods are increasingly favored for remediating polluted environments due to their environmental compatibility and reagent-saving ***,a comprehensive understanding of recent progress,mechanisms,and trends in thesemethods is currently *** of Science(WoS)databases were utilized for searching the primary data to understand the knowledge structure and research trends of publications on electrochemical methods and to unveil certain hotspots and future trends of electrochemical methods *** original data were sampled from 9080 publications in those databases with the search deadline of June 1st,*** and VOSviewer software facilitated data visualization and analysis of document quantities,source journals,institutions,authors,and *** discussed principles,influencing factors,and progress related to seven major ***,publications on this subject have experienced significant growth since *** most frequently-investigated areas in electrochemical methods included novel materials development,heavy metal remediation,organic pollutant degradation,and removal mechanism identification.“Advanced oxidation process”and“Nanocomposite”are currently trending *** major remediation mechanisms are adsorption,oxidation,and *** efficiency of electrochemical systems is influenced by material properties,system configuration,electron transfer efficiency,and power ***-Fenton exhibits significant advantages in achieving synergistic effects of anodic oxidation and electro-adsorption among the seven *** research should prioritize the improvement of electron transfer efficiency,the optimization of electrode materials,the exploration of emerging technology coupling,and the reduction in system operation and maintenance costs.

关键词： Electrochemical remediation Bibliometric analysis Heavy metals Organic pollutants Electrode materials

In situ anchoring in carbon matrix of Bi_(2)O_(2)CO_(3) as a high-performance anode material for Li-ion batteries

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Rare Metals 2024年第8期43卷 3634-3646页

作者： pu-Qiang He Jun Guo Hui huang Zhong-Cheng Guo Faculty of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Research Center of Metallurgical Electrode Materials Engineering Technology Kunming 650106China Kunming Hendera Science and Technology Co. Ltd.Kunming 650106China

Bismuth-based anode materials have been regarded as promising Li-ion batteries due to their high theoretical ***,their low conductivity and associated volume expansion inhabited their *** this work,Bi_(2)O_(2)CO_(3)@C composites were successfully synthesized by in situ anchoring of flower-like Bi_(2)O_(2)CO_(3) nanosheets on a carbon-based substrate via *** unique composited structure of Bi_2O_(2)-CO_(3)@C leads to a stable specific capacity of 547 mAh·g^(-1)after 100 cycles at a current density of 0.1 A·g^(-1).Notably,it demonstrates excellent rate capability with a specific capacity of 210 mAh·g^(-1)at 5 A·g^(-1).After 550 cycles at a current density of 0.5 A·g^(-1),a high reversible capacity of nearly 400 mAh·g^(-1)was ***,in situ X-ray diffraction measurements clearly demonstrate the conversion between Bi and Li_(3)Bi during alloying/dealloying,confirming the good electrochemical reversibility of the materials for Li *** reaction kinetics of Bi_(2)O_(2)CO_(3)@C were further investigated using galvanostatic intermittent titration ***,Bi_2O_(2)-CO_(3)@C exhibited excellent long-term stability,maintaining its high reversible capacity for over 200 cycles at a current density of 0.5 A·g^(-1)in a full cell configuration using Li_(1.20)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2) as the cathode *** result further underscores its promising potential for lithium-ion *** work may provide inspiration for the design of alloy-type negative electrode materials for high-performance rechargeable batteries.

关键词： Bi_(2)O_(2)CO_(3) Composite materials Anode materials Full batteries

Modulating the electrode–electrolyte interface enables switchable selectivity in electrocatalytic furfural reduction

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Science China Chemistry 2024年第10期67卷 3193-3194页

作者： Jingfang Zhang yi huang Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education School of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205China College of Chemistry Central China Normal UniversityWuhan 430079China

Furfural(FF),an important bio-based platform molecule,can be valorized to high-value-added chemicals(e.g.,furfuryl alcohol(FA)or 2-methylfuran(MF))through catalytic hydrogenation[1].The traditional thermocatalytic transformation of FF always requires high-temperature and highpressure conditions[2].Accordingly,electrocatalytic hydrogenation is emerging as a promising approach for the selective reduction of FF to FA or MF under environmentally friendly and benign conditions.

关键词： hydrogenation electrolyte selectivity

Optimal Cooperative Secondary Control for Islanded DC Microgrids via a Fully Actuated Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 405-417页

作者： yi Yu Guo-Ping Liu yi huang Peng Shi IEEE Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China School of Electrical and Mechanical Engineering the University of AdelaideSA 5005Australia Research and Innovation Centre Obuda University1034 BudapestHungary

DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately portray the electrical characteristics of actual MGs while is controller design-friendly has kept the issue active. To this end, this paper establishes a large-signal model containing the comprehensive dynamical behavior of the DC MGs based on the theory of high-order fully actuated systems, and proposes distributed optimal control based on this. The proposed secondary control method can achieve the two goals of voltage recovery and current sharing for multi-bus DC MGs. Additionally, the simple structure of the proposed approach is similar to one based on droop control, which allows this control technique to be easily implemented in a variety of modern microgrids with different configurations. In contrast to existing studies, the process of controller design in this paper is closely tied to the actual dynamics of the MGs. It is a prominent feature that enables engineers to customize the performance metrics of the system. In addition, the analysis of the stability of the closed-loop DC microgrid system, as well as the optimality and consensus of current sharing are given. Finally, a scaled-down solar and battery-based microgrid prototype with maximum power point tracking controller is developed in the laboratory to experimentally test the efficacy of the proposed control method.

关键词： DC microgrids distributed control high-order fully actuated system approach linear quadratic regulator microgrid modeling secondary control

Experimental analysis of matrix moveable oil saturation in tight sandstone reservoirs of the south Ordos Basin,China

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Energy Geoscience 2024年第1期5卷 184-195页

作者： Ting Xu Jun pu Xuejie Qin yi Wei Science and Technology Development Department Petroleum Exploration&Production Research InstituteSINOPECBeijing100083China Center Research Department of North China Petroleum Exploration&Production Research Institute SINOPECBeijing100083China Oil Field Development Department Petroleum Exploration&Production Research InstituteSINOPECBeijing100083China

Tight oil reservoirs in the south Ordos Basin are characterized by fractured,heterogeneous oil-bearing strata(an oil saturation of less than 55%on average),normal pressure(0.8±)and extra-low permeability(less than 0.3 mD).In the Chang 8 tight sandstone reservoir in Honghe oilfield,micro-and nanopores,especially those with a pore-throat radius of less than 1 mm,account for more than 90%.Fluid flow in the matrix is non-linear and crude oil flow rates are very low under normal pressure *** improved understanding of oil mobility in a tight matrix is key to further development of normalpressure tight-oil resources in the continental *** this study,constant-velocity and high-pressure mercury injection experiments were conducted using samples of typical tight sandstone cores obtained from the south of Ordos Basin.A new method for reconstructing the full-scale pore-throat distribution characteristics of tight sandstone reservoirs was established successfully,based on which multistage centrifugal tests,tests of low-pressure differential displacement of oil by water,and nuclear magnetic resonance tests were conducted in order to obtain the distribution characteristics of moveable fluid in different *** moveable oil saturation(MOS)and degree of oil recovery(*** of accumulative oil production to producing geologic reserves)of the core samples under different differential pressures for displacement were *** for the tight oil reservoirs in the south Ordos Basin,the moveable fluids are mainly stored in sub-micron(0.10-0.5 mm)*** Type I reservoirs(k>0.1 mD),the volume percentage of moveable fluid in pores with a radius larger than 0.5 mm is relatively high(greater than 40%).The degree of oil recovery of water flooding serves as the basis for forecasting recoverable reserves for tight oil *** reserves under water flooding,mainly occur in pores with a radius greater than 0.5 *** contribution of Type I reserves to oil pro

关键词： Tight reservoir Pore-throat structure Moveable fluid volume Moveable oil saturation(MOS) Waterflooding oil recovery South Ordos basin

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： yi-jing Hu yi Qu Qin Wu Biao huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

Microstructure evolution of Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)amorphous alloy after semi-solid isothermal treatment

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China Foundry 2024年第3期21卷 287-294页

作者： Xin-hua huang Jing-wen pu Yong-xin Luo Yue-jun Ouyang School of Material Electricity and Intelligent ManufacturingHuaihua UniversityHuaihua 330031HunanChina Hunan Renewable Aluminum Innovation Research Center Huaihua UniversityHuaihua 330031HunanChina

The as-cast amorphous Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14)composites,comprising in situ formedβ-Ti ductile crystalline precipitates,were prepared by water cooled copper mold suction ***,the semi-solid composites were obtained after the as-cast composites were treated by semi-solid isothermal *** microstructure evolution and kinetics of the composites were *** show that the microstructures of both the as-cast and semi-solid composites comprise ofβ-Ti crystal phases and amorphous matrix *** and after treatment,the crystals evolve from fine granular or fine dendritic crystals to coarse *** the treatment temperature increasing or the time prolonging,the average crystal size gradually increases and the surface morphology of the crystals gradually becomes *** studying the microstructural evolution and dynamics during the isothermal treatment process,it is found that the final morphology ofβ-Ti crystals is influenced by the isothermal treatment temperature and time(t),and theβ-Ti evolution rate increases with an increase in treatment *** addition,a linear relationship was observed between the size of cubicβ-Ti crystals(D^(3))and t;the growth kinetics factor K is 3.8μm^(3)·s^(-1).As the K value closes to 4μm^(3)·s^(-1),it is inferred the morphology evolution ofβ-Ti crystals is a coarsening behavior controlled by the diffusion of solute elements.

关键词： Ti_(48)Zr_(27)Cu_(6)Nb_(5)Be_(14) amorphous matrix composites semi-solid as-cast microstructure