Geochemical characteristics of aromatic hydrocarbons in crude oils from the Linnan Subsag,Shandong Province,China

Abundant aromatic fractions were detected in oils from the Linnan subsag, including aphthalenes, phenanthrenes, triaromatic steroids, biphenyl, fluorenes, dibenzothiophenes, dibenzofuranes, as well as some typical higher plant-sourced compounds, such as pyrene, benzopyrene, fluoranthene, chryaene, benzofluoranthrene, perylene and cadalene. Occurrences of biomarkers indicate that oils from the Linnan subsag are typical terrestrially genetic oils. Developed in the depositional environment is a strong reduction condition typical of brackish-saline lake. Thermal evolution has entered into the mature-high mature stage.     

基于POI大数据的沈阳市住宅与零售业空间关联分析

城市住宅及其价格与区域商服业的空间关联性量化研究是人文-经济地理学的重要研究内容。以辽宁省沈阳市为案例,以住宅和零售业兴趣点（Point of Interest, POI）为数据源,基于空间核密度分析提取住宅和各类零售业的空间聚类形态,量化表达商住空间布局的相关性,并在此基础上运用地统计方法测算房价的空间异质性及其与零售业态空间布局的差异特征。结果表明,零售业的整体空间聚集特征与住宅相似,呈现中心城区块状聚集、外围城区多中心离散的分布格局;零售业与住宅核密度相关系数为0.95,超市、便利店等小规模的零售业与住宅密度相关性较强,商场商厦的聚集效应落后于城市住宅,大型零售业应该在铁西经济技术开发区等住宅密集区规划选址,为居民提供高端购物服务;住宅价格的倒“U”型空间分布模式与零售业空间密度的圈层衰减特征相符。     

Experimental Study of Coal–Gas Outburst: Insights from Coal–Rock Structure,Gas Pressure and Adsorptivity

Natural Resources Research - Coal–gas outburst is a complex dynamic phenomenon in underground coal mines that has occurred frequently over the past 150 years. This phenomenon has...     

三维激光扫描技术在地铁隧道形变检测中的应用

地铁隧道正上方堆放大量渣土导致还未运营的线路结构产生严重形变,全站仪测量方式很难准确测绘出形变大小。提出应用三维激光扫描技术,应对隧道受损区域的检测和修复工作。首先,阐述了应用快速绝对定位方式进行点云数据采集,其次利用自行开发的隧道点云数据处理软件,进行了隧道断面切割和收敛分析;最后分析了三维激光扫描仪对比全站仪进行隧道形变检测的特点和优势,论证了三维激光扫描技术应用在地铁隧道结构形变检测的可行性。     

Modelling soil solute release and transport in run‐off on a loessial slope with and without surface stones

Stone covers on loessial slopes can increase the time of infiltration by slowing the velocity of the overland flow, which reduces the transport of solutes, but few mechanistic models have been tested under water‐scouring conditions. We carried out field experiments to test a previously proposed, physically based model of water and solute transport. The area of soil infiltration was calculated from the uncovered surface area, and Richards' equation and the kinematic wave equation were used to describe water infiltration and flow along slopes with stone covers. The transport of chemicals into the run‐off from the surface soil, presumably by diffusion, and their movement in the soil profile could be described by the convection–diffusion equations of the model. The simulated and measured data correlated well. The stones on the soil surface reduced the area available for infiltration but increased the Manning coefficient, eventually leading to increased water infiltration and decreased solute loss with run‐off. Our results indicated that the traditional model of water movement and solute migration could be used to simulate water transport and solute migration for stone‐covered soil on loessial slopes.     

Horizontal hydraulic conductivity of shallow streambed sediments and comparison with the grain‐size analysis results

Streambed horizontal hydraulic conductivity (K_h) has a substantial role in controlling exchanges between stream water and groundwater. We propose a new approach for determining K_h of the shallow streambed sediments. Undisturbed sediment samples were collected using tubes that were horizontally driven into streambeds. The sediment columns were analysed using a permeameter test (PT) on site. This new test approach minimizes uncertainties due to vertical flow in the vicinity of test tube and stream stage fluctuations in the computation of the K_h values. Ninety‐eight PTs using the new approach were conducted at eight sites in four tributaries of the Platte River, east‐central Nebraska, USA. The K_h values were compared with the nondirectional hydraulic conductivity values (K_g) determined from 12 empirical grain‐size analysis methods. The grain‐size analysis methods used the same sediment samples as K_h tests. Only two methods, the Terzaghi and Shepherd methods, yielded K_g values close to the K_h values. Although the Sauerbrei method produced a value relatively closer to K_h than other nine grain‐size analysis methods, the values from this method were not as reliable as the methods of Terzaghi and Shepherd due to the inconsistent fluctuation of the average estimates at each of the test sites. The Zunker, Zamarin, Hazen, Beyer, and Kozeny methods overestimated K_h, while the Slichter, US Bureau of Reclamation (USBR), Harleman, and Alyamani and Sen methods underestimated K_h. Any of these specific grain‐size methods might yield good estimates of streambed K_h at some sites, but give poor estimates at other sites, indicating that the relationship between K_g and K_h is significantly site dependent in our study. Copyright © 2011 John Wiley & Sons, Ltd.     

黄河流域甘肃段县域“三生”功能空间时空格局及影响因素识别

通过构建“三生”功能综合评价指标体系,集成运用熵权法、层次分析法和地理探测器等方法,结合GIS空间分析,对2006—2018年黄河流域甘肃段57个县域“三生”功能进行综合评估,揭示其时空演化和分异特征,并定量识别其影响因素。结果表明：黄河流域甘肃段县域“三生”功能指数总体呈增强趋势,但空间差异较为显著,总体上沿黄河干流“玛曲-靖远”轴线较高而两侧相对较低;“三生”功能具有明显的空间正相关性,其中,生态功能集聚特征最为显著;“三生”功能均随时间变化,正相关类型集聚明显,呈“组团”式分布,负相关类型集聚性低,呈“零星”状的规律;城乡一体化水平是影响研究区“三生”功能空间分异的主导因素,且要素交互作用增强了“三生”功能的空间分异。     

粤港澳大湾区治理框架比较研究：基于制度环境视角

随着粤港澳大湾区上升为国家战略,湾区治理成为学术界关注的重要议题。文章构建包括权力结构、法律结构和社会资本结构3个维度的湾区治理制度环境比较研究框架,运用文本/桌面分析法,系统总结了大湾区与旧金山和东京湾区的治理框架,比较分析了3个湾区治理的制度环境;研究认为,湾区治理的模式特征及其效果与由权力结构、法律结构和社会资本结构构成的制度环境密切相关;权力结构影响着治理的灵活弹性,粤港澳大湾区权力结构呈现非对称和碎片化特征,总体较为封闭集中,导致治理模式单一,始终以政府为主导;法律结构影响着治理的交易成本,粤港澳大湾区尚未形成统一高效的法律体系结构,导致治理过程中的交易成本较高;社会资本结构影响着治理的多元参与和湾区凝聚力,粤港澳大湾区正向社会资本相对薄弱,多元参与治理不足,湾区自下而上的凝聚力不强。最后建议大湾区治理宜从权力、法律和社会资本结构入手,探索三地各自优势下的制度空间灵活重构;在制度环境建设中,引导非政府主体稳定有序参与治理,以提升大湾区凝聚力;在保证中央和省政府的权威方针基础上,适时探索大湾区地方政府的放权自治。     

Application of electrical resistivity tomography to evaluate the variation in moisture content of waste during 2 months of degradation

Moisture content is considered to play an important role in the degradation of municipal solid waste (MSW). The present study was carried out to test the use of electrical resistivity tomography (ERT) to estimate the daily variations in the volumetric moisture content (VMC) during waste degradation. The degradation of MSW in a laboratory-scale reactor was monitored daily by ERT and time domain reflectometry (TDR) over a period of 55 days after the waste was landfilled. The bulk electrical resistivity, normalised to a standard temperature of 25 °C, was compared to the VMC obtained by TDR. The relationship between the bulk electrical resistivity and the VMC was not obvious in the upper unit, because there was a bias in the positions of the ERT and TDR measurements due to the settling of the waste. However, the bulk electrical resistivity depended on the VMC in the lower unit of the reactor. According to a power equation fitted in the lower unit, the 2-D distributions of the VMC are presented. Variations in the VMC reflected the processes of waste degradation and leachate transportation. Furthermore, the volume of water stored in the lower unit of the reactor was calculated and found to be consistent with that estimated from the gravimetric moisture content during waste sampling. The data showed that ERT could be used to estimate the variations in moisture content in the initial period following the landfilling of waste.     

东非裂谷系西支构造样式及其对油气成藏的控制作用

基于东非裂谷系西支地震地质综合解释对比研究,发现该生长型裂谷盆地受基底属性影响,主要发育陡断面地堑型盆地结构,沿边界主控断裂走向发育背离型和接近型两类主要调节构造,沿边界主控断裂倾向主要发育地垒式和地堑式两类调节构造。构造样式控制了主要成藏条件：陡断面地堑式裂谷能够形成沉积范围广、厚度大的湖相优质烃源岩;裂谷间走向调节构造属于一级调节带,控制长轴辫状河三角洲的展布;裂谷内错断的边界断裂带属于次级走向调节构造,控制中小型扇三角州的发育。倾向调节构造形成的断鼻、断块圈闭,为该类盆地的主要油气藏类型。