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Influence of phosphate on deposition and detachment of TiO2 nanoparticles in soil

Frontiers of Environmental Science & Engineering 2019年第5期13卷 163-173页

作者： Zhan Wang Chongyang Shen Yichun Du Yulong Zhang Baoguo Li Department of Soil and Water Sciences China Agricultural UniversityBeijing 100193China College of land and Environment Shenyang Agricultural UniversityShenyang 110866China Key Laboratory of Degraded and Unused land Consolidation Engineering Ministry of Land and ResourcesShaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China

The widespread use of TiO2 nanoparticles (NPs) makes inevitable their release into the soil. Phosphate is also widespread within soil, and is likely copresent with TiO2 NPs. However, the influence of phosphate on deposition/release— and thereby on transport— of TiO2 NPs in soil is yet to be elucidated. In this study we conducted saturated column experiments to systematically examine the transport of TiO2 NPs in soil amended with phosphate at different ionic strengths (ISs) (1, 10, 100 mmol/L NaCl) and pHs (4 and 9). Results show that the deposition of TiO2 NPs decreased with decreasing IS, increasing pH, and when soil absorbed phosphate. These observations are qualitatively in agreement with Derjaguin-landau-Verwey-Overbeek (DLVO) interaction energy calculations, because the repulsive energy barrier is larger and secondary minimum depth is smaller at a lower IS, higher pH, and in the presence of phosphate. Accordingly, both primary- and secondary-minimum deposition were inhibited. Interestingly, although the deposition was less at higher pH and in the presence of phosphate, the subsequent spontaneous detachment and detachment by reduction of solution IS in these cases were greater. In addition, the presence of phosphate in the solution can cause a small quantity of attached TiO2 NPs to detach, even without perturbations of physical and chemical conditions. Our study was the first to investigate the influence of phosphate on detachment of TiO2 NPs and the results have important implication for accurate prediction of fate and transport of TiO2 NPs in subsurface environments.

关键词： Phosphate TiO2 nanoparticles transport Soil Deposition Detachment

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Spatial-temporal Pattern and Differences of land Use Changes in the Three Gorges Reservoir Area of China during 1975-2005

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Journal of Mountain Science 2011年第4期8卷 551-563页

作者： CAO Yingui ZHOU Weit WANG Jing YUAN Chun School of land Science and Technology China University of Geosciences Betiing 100083 China land Key Laboratory China Land Survey and Plan Institute BeO'ing 1o0035 China

Regional land use changes are an important part of global *** research on land use changes in the Three Gorges Reservoir Area of China attracts a lot of attention owing to the Three Gorges Dam *** Three Gorges Reservoir Area becomes one of the important research *** study analyzed the transforming processes and traits of each land use type and the regional differences of land use changes during the past 30 years,summarized the distribution of different land use types in different buffer zones and regresses the equation areas and different buffer distances based on buffer analyses and regression analyses,and then analyzed the transforming rules in different buffer distances,got the optimal influence *** research results indicate that,(1) cultivated land lies at the northwest of the reservoir and was decreasing,however,the construction land was increasing,especially the urban construction land,a large number of land was flooded because of the reservoir water level rise;(2) urban area was sprawling quickly in developed and neighboring areas,and a great deal of cultivated land and a considerable amount of grassland were occupied;in the earlier time,rural settlements occupied lots of cultivated land and a sum of forestry land in the later time;(3) the optimum influenced distances for cultivated land and forestry land were 10-35 km,and for urban and rural settlements were in 5-20 ***,this research can reflect the spatial-temporal characteristics of land use changes during the 30 years,and it is helpful for urban planning and land use planning in the reservoir area.

关键词： land use Spatial-temporal changes Differences Three Gorges Reservoir Area

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Discrete Choice Models and Artificial Intelligence Techniques for Predicting the Determinants of transport Mode Choice--A Systematic Review

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Computers, Materials & Continua 2024年第11期81卷 2161-2194页

作者： Mujahid Ali Department of transport Systems Traffic Engineering and LogisticsFaculty of Transport and Aviation EngineeringSilesian University of TechnologyKatowice40019Poland

Forecasting travel demand requires a grasp of individual decision-making ***,transport mode choice(TMC)is determined by personal and contextual factors that vary from person to *** characteristics have a substantial impact on travel behavior(TB),which makes it important to take into account while studying transport *** statistical techniques frequently presume linear correlations,but real-world data rarely follows these presumptions,which may make it harder to grasp the complex *** systematic review was conducted to examine how machine learning(ML)approaches might successfully capture nonlinear correlations that conventional methods may ignore to overcome such *** in-depth analysis of discrete choice models(DCM)and several ML algorithms,datasets,model validation strategies,and tuning techniques employed in previous research is carried out in the present ***,the current review also summarizes DCM and ML models to predict TMC and recognize the determinants of TB in an urban area for different transport *** two primary goals of our study are to establish the present conceptual frameworks for the factors influencing the TMC for daily activities and to pinpoint methodological issues and limitations in previous *** a total of 39 studies,our findings shed important light on the significance of considering factors that influence the *** adjusted kernel algorithms and hyperparameter-optimized ML algorithms outperform the typical ML ***(random forest),SVM(support vector machine),ANN(artificial neural network),and interpretable ML algorithms are the most widely used ML algorithms for the prediction of TMC where RF achieved an R2 of 0.95 and SVM achieved an accuracy of 93.18%;however,the adjusted kernel enhanced the accuracy of SVM 99.81%which shows that the interpretable algorithms outperformed the typical *** sensitivity analysis indicates that the most sign

关键词： Machine learning techniques AI transport mode choice discrete choice model sustainable transportation

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Bus evacuation during no-notice disasters in downtown areas: A case study of the Zhongguancun area, Beijing

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Journal of Safety Science and Resilience 2022年第3期3卷 235-242页

作者： Xingang Li Xiaodan Cui Rui Jiang Bin Jia Key Laboratory of transport Industry of Big Data Application Technologies for Comprehensive transport Beijing Jiaotong UniversityBeijing 100044China

This paper focuses on the bus evacuation problem with pedestrians’short-distance walking ability between bus stations during no-notice disasters in downtown areas.A mixed-integer linear programming model is proposed to solve this *** objective function is to minimize the evacuation time and number of *** model obtains the flow of evacuees and buses on each arc to the route of buses in the process of ***,a real-time bus evacuation demand estimation method is proposed based on smart card ***,the example of Zhongguancun area in Beijing is used to verify the practicality and validity of the *** results show that pedestrian short-distance walking can effectively reduce casualties and improve the utilization rate of buses.

关键词： No-notice disaster Bus evacuation Short-distance walking Mixed integer linear programming

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Effect of ion and electron beam irradiation on surface morphology and optical properties of PVA

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Nuclear Science and Techniques 2015年第6期26卷 74-79页

作者： H.M.Eyssa M.Osman S.A.Kandil M.M.Abdelrahman Radiation Chemistry Department National Center for Radiation Research and Technology Atomic Energy authority (second research reactor) Cyclotron Project Nuclear Research Center Egypitation Atomic Energy Authority Accelerators & Ion Sources Dept. Nuclear Research CenterAtomic Energy Authority

Polyvinyl alcohol(PVA) is a well-known friendly polymer for paper-making, textiles, and a variety of coatings, biomedical applications such as artificial pancreas, synthetic vitreous body, wound dressing, artificial skin,and cardiovascular device. In this paper, ion/electron beam is employed to get insight into the irradiation effect on surface morphology and optical properties of PVA polymer. UV-Vis spectra are recorded to investigate the effect of induced defects on the optical band gap and the formed carbon clusters size. Scanning electron microscopy(SEM) is used to relate and investigate surface morphology and optical properties of the target polymer with different doses(15, 30 and 60 min). Also, PVA polymer is subjected to theoretical studies by using semi-empirical PM7 quantum chemical method.

关键词：电子束辐照光学性质表面形貌聚乙烯醇离子扫描电子显微镜乙烯醇聚合物紫外-可见光谱

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新加坡发展高质量地铁网络的经验(英文)

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北京规划建设 2007年第3期 35-39页

作者： Lim Bok Ngam Deputy Chief Executive of land transport authority Singapore Mr.

This paper shares some experiences of developing a good metro network in Singapore. After providing a background of the local land transportation scene, the paper provides a chronological discussion of the metro development in Singapore where the characteristics of each new metro line was briefly discussed. The next part of the paper shares some features and initiatives through developing the Singapore metro system over the years, such as funding arrangement, bringing artworks to transit stations, integrated planning between road and rail, integration between transit facilities with non-transit developments, barrier-free accessibility and improving connectivity to the metro stations, and transforming transport nodes into lifestyle hubs. Finally, the paper concludes by discussing the challenges on the land transport system in Singapore and the way forward.

关键词：新加坡高质量地铁网络经验铁路建设

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Study of Three Different Types of Plasma Ion Sources

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Plasma Science and Technology 2009年第5期11卷 604-608页

作者： M.M.ABDELRAHMAN H.EL-KHABEARy Accelerators & Ion Sources Department Nuclear Research CenterAtomic Energy Authority

Three types of plasma ion sources designed, manufactured and optimized in the Accelerators and Ion Sources Department, Nuclear Research Center, Atomic Energy authority are introduced. Different means were investigated to generate the discharge current and ion beam current extracted from the plasma. The various plasmas described include a DC glow discharge plasma, an arc discharge plasma and a radio frequency discharge plasma.

关键词： ion sources ionization processes sputtering and etching processes

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The dynamics of the floodwater and the damaged ship in waves

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Journal of Hydrodynamics 2015年第5期27卷 689-695页

作者：高志亮 VASSALOS Dracos Research Center of Coastal and Estuarine Engineering Tianjin Research Institute for Water Transport EngineeringMinistry of Transport Department of Naval Architecture and Marine Engineering University of Strathclyde

The interaction between the dynamics of the floodwater and the damaged ship in waves is investigated by applying an integrated method, which couples a seakeeping solver and a Navier-Stokes solver. To reveal the effects of the water flooding and the sloshing on the damaged ship behaviour, the motion of a Ro-Ro ferry in regular beam seas is simulated, including the ship under the intact condition with and without internal water and the ship under a damaged condition. It is found that the shift of the natural roll frequency of a damaged ship and the decrease of its roll response are mainly due to the water sloshing inside the compartment. The effect of the resonant sloshing leads to the presence of a ship＇s second peak response at higher frequencies and it is significantly reduced by the water flooding through the damaged opening. The influence of the flooding and the sloshing on the ship behaviour is small with a further increase of the wave frequency.

关键词： damaged ship flooding sloshing coupled model

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Climatic regionalization mapping of the Murrumbidgee Irrigation Area,Australia

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Progress in Natural Science:Materials International 2009年第12期19卷 1773-1779页

作者： Shahbaz Khan Akhtar Abbas Tariq Rana Sustainable Water Resources Development and Management Section Division of Water SciencesUNESCOIrue Miollis 75015 ParisFrance CSIRO land and Water University CanberraACTAustralia Murray Darling Basin authority CanberraACTAustralia

In this study,spatial analysis techniques were used to generate climatic zoning maps of the East Murrumbidgee Irrigation Area(MIA), *** term climate data were used to analyze and assess regional climatic variation by cluster analysis in a GIS environment. Based on thermal and moisture factors,four variables were chosen to develop climate *** variables include annual average rainfalls, annual average ETc,annual average Growing Day Degree(GDD) and daily average temperature generated from daily climate data of 36 years(1971-2006) on 12 local weather stations as the fundamental elements of regional climate ***-based spatial analysis models are used to map climate sub-regions from sets of climatic parameters derived from regional climate data *** climate zoning schemes are presented by integration of spatial interpolation,spatial cluster analysis and climate indices *** scheme comes with the two climate zones of the West and the East based on spatial cluster analysis according to selected climatic variables, and the other comes with the three comprehensive hydro-thermal zones and the six hydro-thermal balance zones.

关键词： Agro-climatic regionalization Regional climatic variation Climatic zone mapping Murrumbidgee Irrigation Area GIS

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land Use Changes of an Aeolian-Loessial Soil Area in Northwest China: Implications for Ecological Restoration

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Pedosphere 2009年第3期19卷 356-361页

作者： CHEN Yu-Fu LIU Yan-Sui WANG Jing YAN Jian-Ping GUO Xu-Dong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China） Key Laboratory of land Use Institute of Land Surveying ~ Planning Ministry of Land ＆ Resources Beijing 100035（China）

China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigated to illustrate land use changes and their implications for environmental and long-term rural economic development. The farmland in Hengshan County significantly decreased during 1990–2003, whereas forest land and grassland increased. The conversion rates of farmland, orchard land, forest land and construction land varied markedly among different periods: 1990–1995, 1995–2000 and 2000–2003. Conversion of orchard land, grassland and construction land was dominant in 1990–1995, whereas the conversion of farmland to forest land mainly occurred in 2000–2003. The results suggested a profound transition in institutional policy and political economy of land management, including implementation of integrated soil erosion control projects, adoption of a market-oriented economy and the ‘Grain-for-Green’ policy, during this period in China. To achieve long-term sustainable land use in Hengshan County, efforts should aim at increasing off-farm income of rural families as well as establishing land-economizing mechanisms to promote land productivity, in addition to conservation measures.

关键词： Hengshan County land management per capita land area policy sustainable land use

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