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A Comprehensive Experimental Study on Immiscible Displacements in Porous Media:Effects of Capillary Forces,Viscous Forces,Wettability and Pore Geometries

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Journal of Thermal Science 2021年第6期30卷 2137-2149页

作者： HUANG Chao DAI Xiaoye shi changxing shi Lin Department of Energy and Power Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Thermal Science and Power Engineering of Ministry of Education of China Beijing 100084China Key Laboratory for C02 Utilization and Reduction Technology of Beijing Beijing 100084China Department of Mechanical and Industrial Engineering University of Illinois at ChicagoChicago 60607United States

Immiscible displacements in porous media are fundamentally significant for many natural processes and industrial *** extensive work has been done in this field,some limitations still exist due to the difficulty to cover the large number of influencing *** this paper,we present a systematic study involving the coupled influence of capillary forces,viscous forces,wetting properties and pore *** microfluidic experiments with high resolutions,both residual fluid distributions and dynamical invasion processes were clearly captured and quantitatively characterized.A void-filling behavior was identified for drainage as the capillary number Ca *** anomalous void-leaving behavior was found for the case of imbibition with an unfavorable viscosity ratio M,representing many ribbon-like regions invaded at intermediate Ca turned to be not accessible at high Ca.A pore geometry with a large typical pore-throat ratio seemed to enhance the void-leaving *** the dynamical invasion processes,an intermittency behavior was captured in the form of a fluctuation of the increasing rate of the invading saturation with *** intermittency dynamics were most evident for drainage with an unfavorable M.A pore geometry with high porosity acted to suppress the intermittency *** experimental results sketched out a full view of immiscible displacements in porous media under different conditions,and provided a complete dataset which could be used to test the rapid developing pore-scale models.

关键词： immiscible displacements porous media microfluidic experiments fluid distributions intermittency dynamics

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Impacts of socio-economic factors on sediment yield in the Upper Yangtze River

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Journal of Geographical Sciences 2011年第2期21卷 359-371页

作者： DU Jun shi changxing FAN Xiaoli ZHOU Yuanyuan Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

In recent years, the role of human activities in changing sediment yield has become more apparent for the construction of hydraulic engineering and water conservation projections in the Upper Yangtze River, but it has not been evaluated at the macro scale. Taking Sichuan Province and Chongqing City as an example, this paper studies the relationship between socio-economic factors and sediment yield in the Upper Yangtze River based on section data in 1989 and 2007. The results show that sediment yield is significantly correlated with population density and cultivated area, in which the former appears to be more closely related to sediment yield. Moreover, in the relation of sediment yield vs. population density, a critical value of population density exists, below which the sediment yield increases with the increase of population density and over which the sediment yield increases with the decrease of population density. The phenomenon essentially reflects the influence of natural factors, such as topography, precipitation and soil property, and some human activities on sediment yield. The region with a higher population density than critical value is located in the east of the study area and is characterized by plains, hills and low mountains, whereas the opposite is located in the west and characterized by middle and high mountains. In the eastern region, more people live on the lands with a low slope where regional soil erosion is slight; therefore, sediment yield is negatively related with population density. In contrast, in the western region, the population tends to aggregate in the areas with abundant soil and water resources which usually lead to a higher intensity of natural erosion, and in turn, high-intensity agricultural practices in these areas may further strengthen local soil erosion. It is also found that population tends to move from the areas with bad environment and high sediment yield to the areas with more comfortable environment and less sediment

关键词： the Upper Yangtze River socio-economic factors human activities sediment yield

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SEDIMENT HAZARDS IN THE LOWER YELLOW RIVER

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International Journal of Sediment Research 1999年第2期14卷 25-30页

作者： shi changxing (Supported by the National Natural Science Foundation of China) (Institute of Geography, Chinese Academy of Sciences, China)

The main sediment hazards in the lower Yellow River are flooding, channel erosion, desertification of cultivated lands, waterlogging. and soil salinization. Some of the hazards are the direct results of sediment movement and the others are related with sediment movement by the special landforms which themselves are the results of sediment movement. On the one hand, the sediment hazards,such as flooding. bank erosion and soil salinization, are aggravated by serious sediment accumulation in the Yellow River channel and irrigation canals due to heavy sediment load of the rived On the other hand, the distribution of the sediment deposit of different grain sizes is also a main factor influencing flooding, desertification, waterlogging and soil salinization hazards. The paper suggests to change the distribution of sedimentation as a measure of mitigating sediment hazards.

关键词： Sediment hazard The lower Yellow Rived Mitigation of sediment hazard

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Geochronology,petrogenesis,and geological significance of the quartz vein-type copper deposits in Longwei area,north-west Dayaoshan,Guangxi

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Frontiers of Earth Science 2024年第1期18卷 68-82页

作者： Song FU Shehong LI changxing LV Longqing shi Xuhan HU Jinming WU Zhuolin XIE College of Earth Sciences&Engineering Shandong University of Science and TechnologyQingdao 266590China School of Earth Sciences Guilin University of TechnologyGuilin 541006China Xinwen Mining Group Co. Ltd.Huafeng Coal MineTai’an 271409China

Quartz-vein-type copper deposits were discovered in SN-trend ore-bearing structures in north-west Dayaoshan,*** of reports on the precise metallogenic age of these deposit has become a bottleneck in metallogenic research in this *** this study,the quartz vein-type copper mine in Longwei area of Jinxiu was selected as the research *** illite samples in the fault gouges and ore samples were collected for testing and *** on the Re-Os isotope dating study,the age of pyrite isochron,belonging to the Caledonian period,was determined to be 417±25 Ma,whereas that of chalcopyrite isochron belonging to the Indosinian period,was found to be 243±18 *** crystallized considerably earlier than *** obtained EPMA data were combined with rock mineralogical analysis data,Metasomatous mineral pyrite and metasomatic mineral chalcopyrite were identified to have originated from different hydrothermal *** the Indosinian period,copper deposits in the Longwei area underwent pyrite crystallization,pyrite fragmentation,copper-bearing hydrothermal filling,and metasomatism,consolidating and forming *** study determined the mineralisation time and ore sources of copper deposits in the Longwei *** study provides evidence for the existence of Indosinian hydrothermal activities in the north-western Dayaoshan area.

关键词： Re-Os dating electron probe micro-analyser quartz-vein copper deposit Dayaoshan area

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地形扫描数据TIN模型生成DEM的误差计算方法

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地球信息科学学报 2023年第1期25卷 40-48页

作者：师长兴中国科学院地理科学与资源研究所陆地水循环及地表过程院重点实验室北京100101

由地表三维空间数据生产的数字高程模型(DEM)的误差包括从数据误差传递来的误差和因数据数量不足以反映地形起伏造成的信息损失误差。本文给出了由三维空间数据的不规则三角网(TIN)模型栅格化为DEM过程中,通过线性插值将数据随机误差传... 详细信息

由地表三维空间数据生产的数字高程模型(DEM)的误差包括从数据误差传递来的误差和因数据数量不足以反映地形起伏造成的信息损失误差。本文给出了由三维空间数据的不规则三角网(TIN)模型栅格化为DEM过程中,通过线性插值将数据随机误差传递到DEM栅格上的随机误差的解析解,同时利用地基激光扫描仪测量的冲沟地形数据点云,分析得出因信息损失产生的DEM系统和随机误差的估算方法。结果显示信息损失产生的DEM平均高程系统误差和随机误差都与有效测点密度有关,其中有效测点由TIN中包含DEM栅格中心点的所有三角面的3个顶点组成;信息损失产生的DEM平均高程系统误差和随机误差除与有效测点密度相关外,还与地形特征有关,平均高程系统误差与地形整体凹度参数有关,随机误差与地形整体起伏程度参数有关。建立了分辨率为0.1 m×0.1 m的DEM误差估算模型。

关键词：地形扫描 DEM 插值传递误差信息损失误差全局误差 TIN模型

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Evolutionary dynamics of the main-stem longitudinal profiles of ten kongdui basins within Inner Mongolia,China

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Journal of Geographical Sciences 2019年第3期29卷 417-431页

作者： GU Zhenkui shi changxing PENG Jie Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences China University of Geosciences

The longitudinal profiles of main streams of ten kongdui basins within Inner Mongolian Autonomous Region of China were characterized in this study by analyzing a series of quantitative indexes that are relevant to tectonic activity and river action, and by establishing a series of multiple regression models. The results reveal that all longitudinal profiles are concave in shape, with a range of concavity between 1.1 and 3.1, increasing from west to east. Data also show that the concavity of the profiles is significantly negatively correlated with profile length, altitude difference, average altitude, drainage area and sediment load of the basins. Analysis reveals that kongdui basins have suffered from moderate-to-weak tectonic activity over time, again characterized by a west-to-east weakening trend. Stream power also varies along the main channels of the ten kongdui basins; average values in each case fall between 0.8 W/m and 8.4 W/m, generally higher within the middle reaches. This decreasing trend in stream power within the lower reaches of kongdui basins might provide one key explanation for sedimentation there. Data also show that the average stream power in western and central basins tends to be higher than that in eastern examples, even though both the highest and the lowest values are seen within two middle ones. This analysis shows that the longitudinal profile concavity values are mainly controlled by tectonic activity and that the effect of river action is insignificant.

关键词： longitudinal profiles concavity tectonic activity stream power multiple regression models

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强化离心分选的数值模拟研究

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中国矿业大学学报 2014年第3期43卷 478-481页

作者：石常省赵跃民中国矿业大学(北京)化学与环境工程学院北京100083 华北科技学院环境工程系河北燕郊065201 中国矿业大学化工学院江苏徐州221116

探讨了Falcon离心机回收电子废弃物的可行性,分析了离心机中颗粒受力情况,提出了颗粒的动力学方程.运用流体动力学(CFD)软件Fluent6.2对强化离心力场进行了数值模拟,并进行了分选实验研究.结果表明,离心力场使分选机有较低的分选下限,采... 详细信息

探讨了Falcon离心机回收电子废弃物的可行性,分析了离心机中颗粒受力情况,提出了颗粒的动力学方程.运用流体动力学(CFD)软件Fluent6.2对强化离心力场进行了数值模拟,并进行了分选实验研究.结果表明,离心力场使分选机有较低的分选下限,采用Falcon离心机分选-0.5mm级破碎电路板,取得了较好的分选效果,I值为0.01,数量效率为93.17%,错配物总量为4.5%.Falcon离心机可以对电子废弃物有效分选.

关键词：强化离心力场数值模拟分选

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黄河口不同粒度泥沙沉积与扩散分析

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地理研究 2021年第4期40卷 1125-1133页

作者：师长兴中国科学院地理科学与资源研究所陆地水循环及地表过程院重点实验室地貌研究室北京100101

本文采集和收集大量黄河三角洲沉积物剖面和钻孔泥沙粒度资料以及黄河口来沙粒度组成数据,定量研究了黄河口泥沙的沉积与扩散特征。结果显示黄河口来沙以粉砂为主,黏土次之,砂最少,年均中值粒径无长期变化趋势。黄河三角洲平原相泥沙与... 详细信息

本文采集和收集大量黄河三角洲沉积物剖面和钻孔泥沙粒度资料以及黄河口来沙粒度组成数据,定量研究了黄河口泥沙的沉积与扩散特征。结果显示黄河口来沙以粉砂为主,黏土次之,砂最少,年均中值粒径无长期变化趋势。黄河三角洲平原相泥沙与来沙的黏土、粉砂和砂含量无显著差异;前缘相泥沙比来沙的黏土含量较低,砂含量较高;前三角洲相泥沙比来沙的黏土含量明显提高,砂和粉砂含量显著降低。计算了一个亚三角洲分组粒径泥沙的沉积量和扩散量,发现黄河三角洲平原和前缘拦截了来沙中绝大部分砂颗粒、一半以上的黏土颗粒和近3/4的粉砂颗粒,但是向远海扩散的泥沙中粉砂含量超过50%。由于粉砂含量较大,扩散入海的泥沙在近距离内大量沉积在前三角洲上。

关键词：黄河三角洲沉积相泥沙粒度组成泥沙扩散

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Unprecedented sesquiterpene-polycyclic polyprenylated acylphloroglucinol adduct against acute myeloid leukemia via inhibiting mitochondrial complex Ⅴ

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Chinese Chemical Letters 2024年第10期35卷 305-308页

作者： Zhengyi shi Jie Yin Yang Xiao Zhangrong Hou Fei Song Jianping Wang Qingyi Tong changxing Qi Yonghui Zhang Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science andTechnologyWuhan430030China

Monosescinol A(1),the first example of sesquiterpene–polycyclic polyprenylated acylphloroglucinol(PPAP)adduct,which represented a new subclass of PPAP-type natural products,along with two new congeners with normal spiro 6/6/5 tricyclic architecture,were isolated from Hypericum *** A possessed an unprecedented 6/5/5/6/6 pentacyclic carbon skeleton that might be assembled from the 6/6/5 carbon skeleton,via the splitting decomposition of C-3/C-14,and the attack from the C-3 in the PPAP core to C-28 in sesquiterpene *** addition,we have firstly confirmed that 24R configuration was existed in sec–Bu containing PPAPs by single crystal diffraction data analysis of monosescinol B(2),that might provide an enlightenment in the configurational determination of sec–Bu containing ***,further pharmacological research has found that compound 1 exhibited remarkable pharmacological effects against acute myeloid leukemia(AML)cell lines,with direct inhibition of mitochondrial complex V and an increase in mitochondrial membrane potential,and led to an induction of oxidative stress,endogenous inflammation,and apoptosis of AML cells.

关键词： PPAP adduct Single-crystal X-ray diffraction Keto-enol tautomerism Plausiblebiosynthetic pathway Cytotoxic activity

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黄河上游内蒙古段河床演变及其与水沙变化的关系

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地理科学 2016年第6期36卷 895-901页

作者：师长兴中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101

对黄河内蒙古段河道大断面进行了连续4 a的测量,分析了断面泥沙冲淤与形态调整的变化过程;通过对河床形态指标变化与水沙条件的相关分析,揭示了河床调整主要的影响因素。结果显示:近4 a内不存在河槽萎缩的现象,整个河段河道存在总的冲... 详细信息

对黄河内蒙古段河道大断面进行了连续4 a的测量,分析了断面泥沙冲淤与形态调整的变化过程;通过对河床形态指标变化与水沙条件的相关分析,揭示了河床调整主要的影响因素。结果显示:近4 a内不存在河槽萎缩的现象,整个河段河道存在总的冲刷降低的趋势,继承了自2004年以来该段河道以深度加大为主,河槽逐渐缓慢扩大的变化方向。整个河段平均从2011年汛后至2014年汛后,全断面冲刷了64 m2,河槽河底降低了0.16m,河槽断面面积增加了4.4%,平均深度增加了4.9%,河槽宽度只增加了0.88%,河槽宽深比减小了4.8%。河槽冲刷和形态调整主要发生在2011年汛后至2012年汛后期间,与2012年较大的洪峰有关。分析河槽冲淤和断面形态变化与水沙条件的关系,结果显示滩唇高度、河槽过水面积、平均深度及宽深比变率与流量大小关系密切。滩唇高度、河槽过水面积、平均深度随着流量的增大而增加,宽深比随着流量的增大而减小。相反,河床断面面积和主槽宽度的变化与水沙条件的关系不显著。除了滩唇高度与平均含沙量有关外,平均含沙量和来沙系数与河床冲淤以及河槽形态变化之间关系都不显著。揭示出近年来内蒙河道主槽以垂向冲淤为主,并且流量变化控制着河槽冲淤与形态调整过程。

关键词：黄河上游河槽形态河床演变

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