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Assessment for soil loss by using a scheme of alterative sub-models based on the RUSLE in a Karst Basin of Southwest China

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Journal of Integrative Agriculture 2017年第2期16卷 377-388页

作者： CHEN hao Takashi Oguchi WU pan School of Political Science and Public Administration Huaqiao University Quanzhou 362021 P.R. China Department of Natural Environment Studies The University of Tokyo Kashiwa 277-8568 Japan Center for Spatial Information Science The University of Tokyo Kashiwa 277-8568 Japan College of Resources and Environmental Engineering Guizhou University Guiyang 550025 P.R. China

Accurate assessment of soil loss caused by rainfall is essential for natural and agricultural resources management. Soil erosion directly affects the environment and human sustainability. In this work, the empirical and contemporary model of revised universal soil loss equation （RUSLE） was applied for simulating the soil erosion rate in a karst catchment using remote sensing data and geographical information systems. A scheme of alterative sub-models was adopted to calculate the rainfall erosivity （R）, soil erodibility （K）, slope length and steepness （LS）, cover management （C） and conservation practice （P） factors in the geographic information system （GIS） environment. A map showing the potential of soil erosion rate was produced by the RUSLE and it indicated the severe soil erosion in the study area. Six classes of erosion rate are distinguished from the map： 1） minimal, 2） low, 3） medium, 4） high, 5） very high, and 6） extremely high. The RUSLE gave a mean annual erosion rate of 30.24 Mg ha-1 yr-1 from the 1980s to 2000s. The mean annual erosion rate obtained using RUSLE is consistent with the result of previous research based on in situ measurement from 1980 to 2009. The high performance of the RUSLE model indicates the reliability of the sub-models and possibility of applying the RUSLE on quantitative estimation. The result of the RUSLE model is sensitive to the slope steepness, slope length, vegetation factors and digital elevation model （DEM） resolution. The study suggests that attention should be given to the topographic factors and DEM resolution when applying the RUSLE on quantitative estimation of soil loss.

关键词： soil erosion RUSLE GIS Karst Basin

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Equivalent linear model for seismic damage evaluation of single-degree-of-freedom systems representing reinforced concrete structures considering cyclic degradation behavior

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 637-648页

作者： Lulu Yan Ding-hao yu Research Center for Geotechnical and Structural Engineering Technology of Liaoning Province Dalian UniversityDalian116622China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

In this study,a novel equivalent damping ratio model that is suitable for reinforced concrete(RC)structures considering cyclic degradation behavior is developed,and a new equivalent linearization analysis method for implementing the proposed equivalent damping ratio model for use in seismic damage evaluation is *** this end,Ibarra’s peak-oriented model,which incorporates an energy-based degradation rule,is selected for representing hysteretic behavior of RC structure,and the optimized equivalent damping for predicting the maximum displacement response is presented by using the empirical method,in which the effect of cyclic degradation is ***,the relationship between the hysteretic energy dissipation of the inelastic system and the elastic strain energy of the equivalent linear system is established so that the proposed equivalent linear system can be directly integrated with the Park-Ang seismic model to implement seismic damage *** to the simplicity of the equivalent linearization method,the proposed method provides an efficient and reliable way of obtaining comprehensive insight into the seismic performance of RC *** verification demonstrates the validity of the proposed method.

关键词： degrading system equivalent linear system equivalent damping seismic damage RC structures

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Solidification segregation behavior of Nb-containing 310S steel

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Journal of Iron and Steel Research International 2023年第1期30卷 82-87页

作者： yu-tuo Zhang hao Zou School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159LiaoningChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina

The solidification characteristics and segregation behavior of solute elements Nb,Ni,Mn,Si,Cr and C in 0.3 wt.%Nb-310S steel were investigated using the isothermal solidification quenching experiment and Thermo-Calc *** phase transformation for 0.3%Nb-310S steel under equilibrium condition can be summarized as follows:liquid(L)→L+γ(1406℃)→γ(1334℃)→γ+NbC(1322℃)→γ+NbC+M_(23)C_(6)(1006℃)→γ+NbC+M_(23)C_(6)→σ(755℃).The results showed that the solidification began with the formation of primary austenite *** volume fraction of the liquid phase decreased rapidly as the temperature decreased in the initial solidification stage,and then,the liquid phase fraction decreased *** austenite formed,Mn and Ni were enriched in the solid phase,while Nb and C were rejected into the *** was present the highest segregation coefficient in 0.3%Nb-310S austenitic stainless *** segregation of Nb was the most serious,followed by Mn,Ni and *** and Si exhibited slight segregation during the *** solidification was terminated by the formation of NbC phase.

关键词： 310S steel Nb Solidification Segregation Thermo-Calc calculation

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Rainwater utilization and storm pollution control based on urban runoff characterization

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Journal of Environmental Sciences 2010年第1期22卷 40-46页

作者： Mulan Zhang hao Chen Jizhen Wang Gang pan State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Environmental & Municipal Engineering North China University of Water Conservancy and Electric Power Zhengzhou 450011 China

The characteristics of urban runoffs and their impact on rainwater utilization and storm pollution control were investigated in three different functional areas of Zhengzhou City, China. The results showed that in the same rain event the pollutant loads （chemical oxygen demand （COD） and total suspended solids （TSS）） in the sampling areas were in the order of industrial area 〉 commercial area 〉 residential area, and within the same area the COD and TSS concentrations of road runoffs were higher than those of roof runoffs. The first flush effects in roof and road runoffs were observed, hence the initial rainwater should be treated separately to reduce rainwater utilization cost and control storm pollution. The initial roof rainfall of 2 mm in residential area, 5 mm in commercial area and 10 mm in industrial area, and the initial road rainfall of 4 mm in residential area and all the road rainfall in commercial and industrial areas should be collected and treated accordingly before direct discharge or utilization. Based on the strong correlation between COD and TSS （R2, 0.87-0.95） and the low biodegradation capacity （biochemical oxygen demand BOD5/COD 〈 0.3）, a sedimentation process and an effective filtration system composed of soil and slag were designed to treat the initial rainwater, which could remove over 90% of the pollutant loads. The above results may help to develop better rainwater utilization and pollution control strategies for cities with water shortages.

关键词： rainwater utilization water quality initial rainwater sedimentation and filtration

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Grain size-dependent geochemical evidence reveals provenance and implications of aeolian sands,Dinggye region,southern Tibet

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Journal of Mountain Science 2022年第7期19卷 1998-2014页

作者： CHEN You-gui pan Mei-hui hao Ze-wen QI yu-han LI Chen-lu College of Geography and Environment Science Northwest Normal UniversityLanzhou730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou730070China

Identifying geochemical characteristics of aeolian sands on the Qinghai-Tibet Plateau(QTP)is essential for understanding the relationship between earth surface processes and paleoclimatic fluctuations in the ***,we present new geochemical data which provides insight to the sedimentary environment of aeolian sands in the Dinggye region,southern *** sampled aeolian dune sands in a variety of settings,and determined grain size and concentration of major oxides and trace elements in the fine and coarse *** show that aeolian sediments are dominated by fine and medium sands,with a single-peaked frequency curve and a 3-stage probability cumulative *** fine and coarse fractions exhibit considerable heterogeneity in elemental concentrations and ratios and upper continental crust-normalized(UCC)*** geochemical evidence indicates that wind dynamic sorting is responsible for the differentiation between fine and coarse fractions in different types of aeolian sand,rather than sediment ***,fine-fraction sediments are well dispersed and can be differentiated from the coarse fraction,suggesting that they contain more environmental *** scale(MDS)and principal component analysis(PCA)of commonly used tracer elements show that flood plain sediments are the sand source for mobile dunes and nebkhas,and lakeshore sediments are the sand source for climbing sand sheets.

关键词： Aeolian sediments Geochemical characteristics Grain-size composition Provenance Multidimensional scaling Principal component analysis

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Development and application of a neural network based coating weight control system for a hot-dip galvanizing line

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Frontiers of Information Technology & Electronic Engineering 2018年第7期19卷 834-846页

作者： Zai-sheng pan Xuan-hao ZHOU Peng CHEN Institute of Cyber-Systems and Control Zhejiang University Zhejiang SUPCON Research Co. Ltd.

The hot-dip galvanizing line(HDGL) is a typical order-driven discrete-event process in steelmaking. It has some complicated dynamic characteristics such as a large time-varying delay, strong nonlinearity, and unmeasured disturbance, all of which lead to the difficulty of an online coating weight controller design. We propose a novel neural network based control system to solve these problems. The proposed method has been successfully applied to a real production line at Va Lin LY Steel Co., Loudi, China. The industrial application results show the effectiveness and efficiency of the proposed method, including significant reductions in the variance of the coating weight and the transition time.

关键词： Neural network Hot-dip galvanizing line (HDGL) Coating weight control

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Micro-mechanism Study on the Different Antioxidants Protective Effect of Vegetable Oil by ReaxFF Molecular Dynamics

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1269-1279页

作者： haoxi Cong Xuefeng Hu hao pan Qingmin Li State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

The aging problem of vegetable oil has severely restricted the popularization and application of vegetable oil *** antioxidants is the most recommended *** present,there is insufficient research on the micromechanism application of the protective effect of antioxidants on vegetable *** this paper,multiple vegetable oil models with different types and concentrations of antioxidants are *** the molecular dynamics simulation based on ReaxFF is carried out at different temperatures and oxygen *** show that the protective mechanism of antioxidants is to release H and combine this with free radicals generated by the decomposition of unsaturated fatty acids(UFA)in the *** addition,the protective effects of four antioxidants show different *** stronger ones are tert-butyl hydroquinone(TBHQ)and butylated hydroxytoluene(BHT),while the weaker ones are butylated hydroxyanisole(BHA)and propyl gallate(PG).TBHQ has a better protective effect at lower concentrations,but the decomposition of UFA is promoted at higher *** the temperature rises,the decomposition of UFA is *** the addition of oxygen,smaller molecular compounds are easily oxidized,and the decomposition of UFA is *** above research could reveal the microscopic mechanism of antioxidant protection on vegetable oil,providing theoretical references for further exploration of effective vegetable oil aging protection technology.

关键词： Antioxidant molecular dynamics transformer vegetable oil

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Study of the multi-physics field-coupled model of the two-stage electrostatic precipitator

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Building Simulation 2024年第3期17卷 387-398页

作者： Wenjia hao yu Guo yukun Wang Tao yu hao Gao Zhengwei Long Tianjin Key Laboratory of Indoor Air Environmental Quality Control School of Environmental Science and EngineeringTianjin UniversityWeijin Road 92Tianjin300072China Wuhan Second Ship Design and Research Institute WuhanChin

The two-stage electrostatic precipitator is widely used to purify oil mist ***,there is limited research on the influences of relative humidity,particle deposition characteristics,and the generation of gaseous ***,this paper established a numerical model of the electrostatic oil mist purifier and applied it to a two-stage electrostatic *** the model was used to investigate the corona discharge characteristics under different relative humidity conditions in the charged zone,the particle deposition characteristics,the purification efficiency,the ozone concentration distribution,and the oil vapor concentration distribution in the collection *** results indicate that,with a constant temperature,the corona current decreases as relative humidity increase,and there is a quadratic relationship between relative humidity and *** variation in relative humidity has little impact on the purification *** maximum ozone concentration occurs near the electrode line,and its concentration is influenced by the discharge current and inlet airflow *** oil vapor concentration reaches its maximum value at the side plates,with a value of 19 ppb,while it reaches the minimum value at the collecting zone electrode plate,with a value of 2 *** temperature is the main factor affecting the volatilization of the oil film,with higher temperatures resulting in higher oil vapor.

关键词： two-stage ESPs particle deposition corona discharge oil vapor

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Performance of Cooperative Spatial Modulation with AF Protocol in Wireless Relay Network

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Chinese Journal of Electronics 2019年第1期28卷 143-151页

作者： yu Xiangbin pan Qing WANG Cheng College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics National Mobile Communications Research Laboratory Southeast University

By combing Spatial modulation(SM) with the Amplify-and-forward(AF) cooperative communication, a cooperative SM scheme with AF(AF-SM) protocol is presented, and the corresponding Bit error rate(BER)performance is investigated. Based on the performance analysis, the error probability of antenna index estimation(Pa) and the error probability of symbol estimation(Pd),which constitutes the overall average BER, are derived,respectively. As a result, tightly approximate closedform expressions of Paand Pdare attained, *** these expressions, the closed-form overall average BER is achieved. During the analysis, the computational complexity of AF-SM detector is also provided in terms of the complex addition and multiplication ***, the asymptotic BER at high SNR and the corresponding diversity gain are further derived, and the resultant diversity gain of Nr+ 1 is obtained for the system with Nrreceive antennas. Simulation results show that our theoretical analysis is valid, and provides good performance evaluation method for cooperative SM system. Moreover, the BER performance can be effectively improved as Nrincreases due to higher diversity gain.

关键词： Spatial modulation(SM) Cooperative communication Amplify and forward protocol Diversity gain Average bit error rate

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基于功能化COFs材料的样品前处理技术在新兴污染物中的研究进展

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分析测试学报 2025年第1期44卷 12-24页

作者：潘自宇刘智敏许志刚昆明理工大学理学院云南昆明650500

新兴污染物因具有环境持久性、生物累积性、生物毒性以及在环境中痕量存在等特点而备受全球众多国家关注。因此,对环境、食品以及生物样品中的新兴污染物进行高灵敏检测至关重要。传统样品前处理技术存在耗时长、吸附剂用量大,以及对不... 详细信息

新兴污染物因具有环境持久性、生物累积性、生物毒性以及在环境中痕量存在等特点而备受全球众多国家关注。因此,对环境、食品以及生物样品中的新兴污染物进行高灵敏检测至关重要。传统样品前处理技术存在耗时长、吸附剂用量大,以及对不稳定污染物的分析准确性差等缺点,因此,亟需开发设计具有高选择性、高传质效率的新型材料作为前处理技术的吸附剂,以实现新兴污染物的高选择、高灵敏检测。共价有机骨架材料(COFs),特别是功能化的COFs材料,因具有比表面积大、结构可设计、稳定且构筑基元丰富等诸多优点而被广泛用于新兴污染物的富集。该文主要综述了近年来功能化COFs材料的合成策略及其作为样品前处理吸附剂在环境、食品和生物样品中新兴污染物中的分析应用,并对该类材料的未来发展趋势进行了展望。

关键词：新兴污染物功能化COFs材料样品前处理技术

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