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Seasonal variations of organic carbon and nitrogen in the upper basins of Yangtze and Yellow Rivers

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Journal of Mountain Science 2017年第8期14卷 1577-1590页

作者： LI Xiang-ying DING Yong-jian HAN Tian-ding XU Jian-zhong KANG Shi-chang WU Qing-bai Mika Sillanp?? yu zhong-bo yu Cong-rong College of Hydrology and Water Resources/State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Laboratory of Green Chemistry School of Engineering ScienceLappeenranta University of Technology Department of Civil and Environmental Engineering Florida International University

The profound impacts exerted by climate warming on the Tibetan Plateau have been documented extensively, but the biogeochemical responses remain poorly understood. This study was aimed at seasonal variations of total organic carbon(TOC) and total organic nitrogen(TON) in stream water at two gauging sections(TTH, ZMD) in the upper basin of Yangtze River(UBYA) and at fourgauging sections(HHY, JM, JG, TNH) in the upper basin of Yellow River(UBYE) in 2013. Results showed that concentrations of TON exhibit higher values in spring and winter and lower values in summer. TOC exhibits higher concentrations in spring or early summer and lower concentrations in autumn or winter. Seasonal variations of TOC and TON fluxes are dominated by water flux. In total, the UBYE and UBYA delivers 55,435 tons C of organic carbon and 9,872 tons N of organic nitrogen to downstream ecosystems in 2013. Although the combined flux ofTOC from UBYA and UBYE is far lower than those from large rivers, their combined yields is higher than, or comparable with, those from some large rivers(e.g. Nile, Orange, Columbia), implying that organic carbon from the Tibetan Plateau may exert a potentially influence on regional and/or global carbon cycles in future warming climate.

关键词： Seasonal variation Total organic carbon(TOC) Total organic nitrogen(TON) Yangtze River Yellow River

A Dynamic-Order Fractional Dynamic System

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Chinese Physics Letters 2013年第4期30卷 154-157页

作者： SUN Hong-Guang SHENG Hu CHEN Yang-Quan CHEN Wen yu zhong-bo State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering College of Mechanics and MaterialsHohai UniversityNanjing 210098 School of Electronic and Information Engineering Dalian Jiaotong UniversityDalian 116028 Mechatronics Embedded Systems and Automation(MESA LabSchool of EngineeringUniversity of CaliforniaMerced5200 North Lake RoadMercedCA 95343USA State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098

Motivated by the experimental result of an electronic circuit element"fractor",we introduce the concept of a dynamic-order fractional dynamic system,in which the differential-order of a fractional dynamic system is determined by the output signal of another dynamic *** concept offers an explanation for the physical mechanism of variable-order fractional dynamic systems and multi-system *** properties and potential applications of dynamic-order fractional dynamic systems are further explored by analyzing anomalous relaxation and diffusion processes.

关键词： interaction. processes. fractional

Super-high bed sintering for iron ores:behaviors,causes and solutions of horizontal segregation on strand

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Journal of Iron and Steel Research International 2024年第7期31卷 1590-1596页

作者： Liang-ping Xu Hui-bo Liu zhong-lin Dong Qiang zhong yu-chao Zhao Guang-hui Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Horizontal segregation has been a constraint to the development and application of super-high bed *** eliminate the horizontal segregation of super-high bed sintering,several typical sintering machines were sampled and analyzed,and theoretical calculation was made to compare the bed depth and their differences in different areas within the mixture ***,solutions were proposed and applied to a 265 m^(2) sintering *** results showed that the horizontal seg-regation of the 265 m^(2) sintering machine was dominated by particles larger than 8 mm with horizontal segregation degree of 0.48,while 360 and 550 m^(2) sintering machines were affected by 5-8 mm and 1-3 mm particles with horizontal segregation degree of 0.27 and 0.31,*** analysis indicated the different segregation distribution results from the matching of the bed depth of each area within the mixture ***,the horizontal segregation degree not larger than 0.06 was achieved by optimizing the time parameters and the division of three zones on the 265 m^(2) sintering machine.

关键词： Super-high bed sintering Horizontal segregation Feeder Particle distribution Agglomeration

Super-high bed sintering for iron ores:problems ascertainment

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Journal of Iron and Steel Research International 2024年第5期31卷 1063-1070页

作者： Liang-ping Xu Hui-bo Liu yu-chao Zhao Qiang zhong zhong-lin Dong Guang-hui Li Tao Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina

Super-high bed sintering process is an important development direction of iron ore sintering for its lower emission and higher ***,there is a lack of deep understanding of the uneven quality of super-high bed sintering products,and the deterioration of reduction disintegration performance,the thickening of hearth layer and the reduction in energy-saving effect are perplexing enterprises and *** ascertain the problems of super-high bed sintering,ten sintering machines with the areas of 265,280,360,550 and 660 m^(2)and bed depth above 900 mm were sampled and *** results showed that problems were mainly shown in the unevenness of chemical composition,macrostructure,mechanical strength and metallurgical *** chemical composition exhibits severe segregation in both horizontal and vertical directions,with basicity segregation reaching as high as *** uneven macrostructure of sinter is reflected in a 10%difference in porosity and mechanical strength increase in 16%–19%along the vertical *** reducibility and reduction disintegration performance gradually deteriorate along the bed depth,with a difference of 10.5%in reducibility and 7.3%in RDI−0.5 mm(reduction disintegration index of sinter with size smaller than 0.5 mm).

关键词： Super-high bed sintering Uneven sinter performance Segregation Agglomeration Iron ore

Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations

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Journal of Energy Chemistry 2024年第6期93卷 299-305,I0008页

作者： Legeng yu Nan Yao yu-Chen Gao zhong-Heng Fu bo Jiang Ruiping Li Cheng Tang Xiang Chen Tsinghua Center for Green Chemical Engineering Electrification(CCEE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos 017010Inner Mongoli1China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan University2066 Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea

Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium ***,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very ***,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an *** interface model was developed,incorporating the electrode potential and atom *** a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic ***,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,*** preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+*** CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.

关键词： Lithium batteries Graphite N-doping Electric double layer Molecular dynamics Constant potential method Electrode potential

Distribution System Restoration with Cyber Failures Based on Co-dispatching of Multiple Recovery Resources

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1096-1112页

作者： Zhengze Wei Kaigui Xie bo Hu yu Wang Changzheng Shao Pierluigi Siano Jun zhong National Key Laboratory of Power Transmission Equipment Technology Chongqing UniversityChongqing 400044China Department of Management and Innovation Systems University of SalernoFisciano 84084Italyand he is also with the Department of Electrical and Electronic Engineering ScienceUniversity of JohannesburgJohannesburg 2006South Africa Shenzhen Power Supply Co. Ltd.China Southern Power GridShenzhen 518000China

Improving the restoration efficiency of a distribu-tion system is essential to enhance the ability of power systems to deal with extreme *** distribution system restoration(DSR)depends on the interaction among the electric network(EN),cyber network(CN),and traffic network(TN).However,the coordination of these three networks and co-dispatching of multiple recovery resources have been mostly *** paper proposes a novel DSR framework,which is formulated as a mixed-integer linear programming(MILP)*** fail-ures in cyber lines result in cyber blind areas,which restrict the normal operation of remote-controlled *** acceler-ate the recovery process,multiple recovery resources are uti-lized including electric maintenance crews(EMCs),cyber main-tenance crews(CMCs),and emergency communication vehicles(ECVs).Specifically,CMCs and ECVs restore the cyber func-tion of switches in cooperation,and EMCs repair damaged elec-tric *** travel time of these three dispatchable resources is determined by *** effectiveness and superiority of the proposed framework are verified on the modified IEEE 33-node and 123-node test systems.

关键词： Distribution system restoration(DSR) network coupling maintenance crew co-dispatching emergency communicationvehicle

Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： bo Wang zhong Jiang Pei-Da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Mechanical Janus lattice with plug-switch orientation

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 23-26页

作者： yupei Zhang Jiawei zhong Zhengcai Zhao Ruiyu Bai Yanqi Yin Yang yu bo Li State Key Laboratory for Manufacturing System EngineeringShaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Qian Xuesen Honors College Xi’an Jiaotong UniversityXi’an 710049China

In recent years,materials with asymmetric mechanical response properties(mechanical Janus materials)have been found possess numerous potential applications,*** absorption and vibration *** this study,we propose a novel mechanical Janus lattice whose asymmetric mechanical response can be switched in orientation by a *** finite element analysis and experimental verification,this lattice exhibits asymmetric displacement responses to symmetric ***,with such a plug structure inside,individual lattices can switch the orientation of asymmetry and thus achieve reprogrammable design of a mechanical structure with chained *** reprogrammable asymmetry of this material will offer multiple functions in design of mechanical metamaterials.

关键词： Janus Non-reciprocity Programmability Mechanical metamaterial

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： Zhen-yu Ouyang Jian-zhong Lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a *** in the past 20 years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid *** paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle *** this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be ***,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction