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Characteristics and Genesis of Acid Drainage Contamination from a Rock Tunneling Project Site

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Journal of Earth Science 2024年第1期35卷 190-200页

作者： yanyun Li Zejiao luo Shihua Qi Hubei Key Laboratory of Yangtze River Basin Environmental Aquatic Science School of Environmental StudiesChina University of GeosciencesWuhan 430078China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China

While acid mine drainage(AMD)issues have become a topic of global concern,few studies have focused on acid drainage problems of non-mining *** conducted field research and a series of laboratory experiments to investigate the characteristics,release processes and formation of acid drainage *** rock samples and adjacent surface water,groundwater,soil and sediment samples were collected at a railway tunnel construction site in central China,and various parameters,such as the p H,mineral ion concentrations,and heavy metal concentrations,were *** on the measured concentrations,surface water and sediments were seriously contaminated by acids,sulfate salts and heavy *** in surface water showed a decreasing tendency as the distance from the spoils increased,while that in sediments showed a greater influence of coprecipitation and adsorption processes of heavy metal *** eluviation experiments of three rock samples indicated that R2(silty fine sandstone)was the most likely major acid drainage *** ferrooxidans was cultured and isolated from contaminated water to study the oxidation conditions during the release *** significant release of acid drainage when air and bacteria were both in the culture container suggested that oxygen and bacteria were necessary to produce acid drainage from spoils.

关键词： acid mine drainage heavy metals leaching oxidation

Landform classification using soil data and remote sensing in northern Ordos Plateau of China

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Journal of Geographical Sciences 2012年第4期22卷 681-698页

作者： luo yanyun LIU Tingxi WANG Xixi DUAN Limin ZHANG Shengwei SHI Junxiao College of Conservancy and Civil Engineering Inner Mongolia Agricultural UniversityHohhot 010018China Hydraulics/Water Resources Laboratory Department of Civil and Environmental EngineeringOld Dominion UniversityNorfolk 23529USA

Landform classification is commonly done using topographic altitude only. However practice indicates that locations at a same altitude may have distinctly different landforms, depending on characteristics of soils underneath those locations. The objectives of this study were to： 1） develop a landform classification approach that is based on both altitude and soil characteristic; and 2） use this approach to determine landforms within a watershed located in northern Ordos Plateau of China. Using data collected at 134 out of 200 sampling sites, this study determined that D10 （the diameter of soil particles 10% finer by weight） and long-term average soil moisture acquired in 2010, which can be estimated at reasonable accuracy from remote sensing imagery, can be used to represent soil characteristics of the study watershed. Also, the sampling data revealed that this watershed consists of nine classes of landforms, namely mobile dune （MD）, mobile semi-mobile dune （SMD）, rolling fixed semi-fixed dune （RFD）, flat sandy land （FD）, grassy sandy land （GS）, bedrock （BR）, flat sandy bedrock （FSB）, valley agricultural land （VA）, and swamp and salt lake （SW）. A set of logistic regression equations were derived using data collected at the 134 sampling sites and verified using data at the remaining 66 sites. The verification indicated that these equations have moderate classification accuracy （Kappa coefficients K 〉 43%）. The results revealed that the dominant classes in the study watershed are FD （36.3%）, BR （27.0%）, and MD （23.5%）, while the other six types of landforms （i.e., SMD, RFD, GS, FSB, VA, and SW） in combination account for 13.2%. Further, the landforms determined in this study were compared with the classes presented by a geologically-based classification map. The comparison indicated that the geologically-based classification could not identify multiple landforms within a class that are dependent upon soil characteristics.

关键词： landform classification remote sensing soil physical characteristic logistic topography northernOrdos Plateau

Influences of landform as a confounding variable on SOM-NDVI association in semiarid Ordos Plateau

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Journal of Arid Land 2012年第4期4卷 450-456页

作者： yanyun luo TingXi LIU XiXi WANG LiMin DUAN College of Water Conservancy and Civil Engineering Inner Mongolia Agricultural University Hohhot 010018 China Hydraulics/Water Resources Laboratory Department of Civil and Environmental Engineering Old Dominion University NorfolkVA 23529-0241 USA

Soil organic matter （SOM） plays an important role in maintaining vegetation cover and thus mitigating land erosion of fragile terrestrial ecosystems such as in the Northern Ordos Plateau of China （NOPC）. However, little information is available on whether and how SOM varies spatially as an intrinsic characteristic of landform in NOPC. The objective of this study was to examine the spatial associations of SOM with landform and vegetation cover. The study was conducted in a 23,000-km2 area within NOPC because this area has landforms of mobile dunes （MD）, flat dunes （FD）, grassy sandy land （GSL）, flat sandy bedrocks （FSB）, and swamps and salt lakes （SW）, which are typical landforms in semiarid ecosystems. SOM was determined using a standard laboratory analysis method for 5 cm topsoil samples collected at 72 locations across the study area. In addition, the 250 m Multitem- poral Moderate Resolution Imaging Spectroradiometer （MODIS） imageries taken in the period from August 2006 to August 2010 were used to extract Normalized Difference Vegetation Index （NDVI） which in turn was used as the surrogate of vegetation cover. Classic and geostatistical methods were used to compare SOM concentration across different landforms. The results indicated that an area with a greater value for NDVI （i.e. better vegetation cover） tended to have a higher SOM concentration regardless of the landform types. However, the association between SOM and NDVI varied from one landform to another. The SW and GSL had a highest SOM concentration, while MD had a lowest concentration. For the study area as a whole and the FD, GSL, and MD, SOM was found to be the sole function of NDVI, whereas, for the FSB, SOM was influenced by several intrinsic variables, namely ground surface altitude, slope, and aspect, as well as NDVI. SOM for the SW landform was found to be a function of NDVI. Furthermore, SOM and NDVI exhibited a consistent spatial pattern of increasing from north to south and from west to east. T

关键词： MODIS NDVI remote sensing soil organic matter spatial pattern topography

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城市高架轨道多层隔振系统影响参数匹配

同济大学学报（自然科学版） 2018年第11期46卷 1520-1527页

作者：刘艳罗雁云上海材料研究所上海200437 同济大学铁道与城市轨道交通研究院上海201804

以轨道交通30m双线混凝土简支箱梁桥为研究对象,考虑扣件-轨道板支承-桥梁支座多层隔振系统内部耦合机理,建立车-轨-桥有限元模型(FEM).通过现场试验数据验证模型有效性.利用该模型展开多工况计算分析,研究各层隔振元件刚度的改变对车... 详细信息

以轨道交通30m双线混凝土简支箱梁桥为研究对象,考虑扣件-轨道板支承-桥梁支座多层隔振系统内部耦合机理,建立车-轨-桥有限元模型(FEM).通过现场试验数据验证模型有效性.利用该模型展开多工况计算分析,研究各层隔振元件刚度的改变对车体、轨道结构、桥梁结构振动响应特性和综合隔振效果的影响规律,获取参数匹配原则.结果表明:高架轨道各层隔振元件宜采用匹配设计,可在改善沿线环境隔振效果的同时,兼顾车-轨-桥各层子系统动力响应特性.

关键词：城市高架轨道扣件轨道板支承桥梁支座参数匹配原则

Effect of climatic change on surface environments in the typical region of Horqin Sandy Land

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Research in Cold and Arid Regions 2010年第2期2卷 143-153页

作者： Long Ma TingXi Liu HongLan Ji yanyun luo LiMin Duan Water Conservancy and Civil Engineering College of Inner Mongolia Agricultural University HohhotInner Mongolia010018China

The town of Agura,a typical region in Horqin Sandy Land,was selected as the study area in this *** 12 remote sensing images and climatic data from the past 20 years,the effects of climate change on surface environments were *** impact indices of climatic factors,along with their corresponding ranks,were used to characterize the responses of different types of surface environments to climate *** show that in the past 20 years,the surface environments of the study area have been ***,there is a positive relationship between the changes in surface environments and those in climatic *** climatic factors influence surface environments in different ways and at different *** most sensitive factor is relative humidity,followed by precipitation and ***,moisture is the key factor that affects the changes in surface environments of arid and semi-arid areas.

关键词： Horqin Sandy Land typical region surface environment climatic change response climatic factor impact index

Development of a Regional Regression Model for Estimating Annual Runoff in the Hailar River Basin of China

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Journal of Water Resource and Protection 2010年第11期2卷 934-943页

作者： Limin Duan Tingxi Liu Xixi Wang yanyun luo Long Wu 不详

The Hailar River, a first-grade tributary of the Erguna River that borders China and Russia, is the main water source for the local industry and agriculture. However, because there are only 11 flow gauging stations and those stations cannot monitor all runoff paths, it is hard to directly use the existing flow data to estimate the annual runoffs from all subbasins of interest although such estimation is needed for utilization and protection of the water resources in the Hailar River. Thus, this study implemented an indirect approach (i.e., regional regression model) by correlating annual runoff with annual rainfall and water surface evaporation as well as hydrologic characteristics of the 11 subbasins monitored by the gauging stations. The study used 51 years (from 1956 to 2006) data. The results indicated a significant correlation (R2 > 0.87) between annual runoff and the selected subbasin characteristics and showed the model to be robust because the predicted runoffs for the validation period are compatible with the corresponding observed values. In addition, this model was used to estimate the annual runoffs for the subbasins that are not monitored by the 11 flow gauging stations, which adds new information to existing literature.

关键词： Inner Mongolia Indirect Estimation Monsoon Climate Subbasin Runoff

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轨道参数变化对无缝线路稳定性影响

中国铁道科学 2008年第2期29卷 33-37页

作者：罗雁云李振廷同济大学铁道与城市轨道交通研究院上海200331 上海铁路局工务处上海200071

通过建立无缝线路轨道胀轨臌曲理论模型,分析无缝线路胀轨时的位移变化规律,研究温度力作用下无缝线路轨道臌曲的变化特征以及轨道参数对其的影响。轨道结构存在着稳定区、胀轨可能发生区、胀轨发生区以及反映臌曲变化特征的胀轨临界轨... 详细信息

通过建立无缝线路轨道胀轨臌曲理论模型,分析无缝线路胀轨时的位移变化规律,研究温度力作用下无缝线路轨道臌曲的变化特征以及轨道参数对其的影响。轨道结构存在着稳定区、胀轨可能发生区、胀轨发生区以及反映臌曲变化特征的胀轨临界轨温点和安全临界轨温点。研究结果表明:理论模拟与试验结果有着比较好的一致性和吻合性;随着轨道扭曲刚度的增加,胀轨临界轨温和安全临界轨温均相应增加,且对安全临界轨温的影响幅度更大;轨道竖向刚度则对胀轨临界轨温的影响大于对安全临界轨温的影响。轨道纵向阻力对轨道的胀轨临界轨温影响不明显;随着轨道横向阻力增大,胀轨临界轨温增加的幅度要大于安全临界轨温增加的幅度。因此,保持轨道有较高的横向阻力对防止轨道臌曲极为重要,尤其在曲线轨道上更为突出。

关键词：无缝线路温度力轨道稳定性轨道参数

ORPOM model for optimum distribution of tree ring sampling based on the climate observation network

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Research in Cold and Arid Regions 2010年第6期2卷 547-554页

作者： Long Ma TingXi Liu yanyun luo HongLan Ji ShiQiang Li JunXiao Shi Water Conservancy and Civil Engineering College of Inner Mongolia Agricultural University Hohhot Inner Mongolia O10018 China

Tree ring dating plays an important role in obtaining past climate *** fundamental study of obtaining tree ring samples in typical climate regions is particularly *** optimum distribution of tree ring sampling sites based on climate information from the Climate Observation Network(ORPOM model) is presented in this *** this setup,the tree rings in a typical region are used for surface representation,by applying excellent correlation with the climate information as the main *** the Horqin Sandy Land in the cold and arid region of China as an example,the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model,which is considered a reasonably practical scheme.

关键词： climate monitoring network tree ring sampling site optimum model Horqin Sandy Land

基于Newmark格式的车辆-轨道耦合迭代过程的改进算法

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中南大学学报（自然科学版） 2016年第1期47卷 298-306页

作者：张斌雷晓燕罗雁云同济大学铁道与城市轨道交通研究院上海201804 华东交通大学铁路环境振动与噪声教育部工程研究中心江西南昌330013

针对车辆-轨道耦合系统振动方程联立求解过程,考虑车辆和轨道2个子系统模型,提出一种将有限元法和非线性接触理论相结合的交叉迭代数值改进算法。该算法将子系统方程非荷载项矩阵进行修正和求逆的预处理,基于Newmark-β积分格式规则,构... 详细信息

针对车辆-轨道耦合系统振动方程联立求解过程,考虑车辆和轨道2个子系统模型,提出一种将有限元法和非线性接触理论相结合的交叉迭代数值改进算法。该算法将子系统方程非荷载项矩阵进行修正和求逆的预处理,基于Newmark-β积分格式规则,构造具有较高收敛速度及精度的松弛因子函数和收敛准则函数,利用轮轨相互作用力在车辆系统与轨道系统之间的快速交叉迭代,改进并实现轮轨耦合关系的求解。研究结果表明:提出的算法正确、有效,极大地提高了动力学方程数值计算效率;时间步长对系统数值解的稳定性影响显著,松弛因子的合理选择,可起到加速系统迭代和增强迭代稳定性的作用;该算法在解决大型工程振动问题时更具高效求解的优越性。

关键词：耦合动力学轮轨相互作用 Newmark-β法交叉迭代过程数值稳定性