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Diagnostic experiments for transport mechanisms of suspended sediment discharged from the Yellow River in the Bohai Sea 被引量:3
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作者 LI Guosheng XUE Xinghua +2 位作者 LIU Ying WANG Hailong LIAO Heping 《Journal of Geographical Sciences》 SCIE CSCD 2010年第1期49-63,共15页
Five diagnostic experiments with a 3D baroclinic hydrodynamic and sediment transport model ECOMSED in couple with the third generation wave model SWAN and the Grant-Madsen bottom boundary layer model driven by the mon... Five diagnostic experiments with a 3D baroclinic hydrodynamic and sediment transport model ECOMSED in couple with the third generation wave model SWAN and the Grant-Madsen bottom boundary layer model driven by the monthly sediment load of the Yellow River, were conducted to separately diagnose effects of different hydrodynamic factors on transport of suspended sediment discharged from the Yellow River in the Bohai Sea. Both transport and spatio-temporal distribution of suspended sediment concentration in the Bohai Sea were numerially simulated. It could be from the Yellow River cannot be delivered in concluded that suspended sediment discharged long distance under the condition of tidal current. Almost all of sediments from the Yellow River are deposited outside the delta under the condition of wind-driven current, and only very small of them are transported faraway. On the basis of wind forcing, sediments from the Yellow River are mainly transported north-northwestward, and others which are first delivered to the Laizhou Bay are continuously moved northward. An obvious 3D structure characteristic of sediment transport is produced in the wind-driven and tide-induced residual circulation condition. Transport patterns at all layers are generally consistent with circulation structure, but there is apparent deviation between the depth-averaged sediment flux and the circulation structure. The phase of temporal variation of sediment concentration is consistent with that of the bottom shear stress, both of which are proved to have a ten-day cycle in wave and current condition. 展开更多
关键词 sediment from the Yellow river suspended transport dynamic mechanism diagnostic experiment
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The Effect of Urban Agglomeration Expansion on PM_(2.5) Concentrations: Evidence from a Quasi-natural Experiment
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作者 LI Sijia WU Lihua 《Chinese Geographical Science》 SCIE CSCD 2023年第2期250-270,共21页
This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expan... This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expansion on fine particulate matter(PM_(2.5)) concentrations through propensity scores in difference-in-differences models(PSM-DID) using panel data from 286 prefecturelevel cities in China from 2003 to 2016. The results show that 1) urban agglomeration expansion contributes to an overall decrease in PM_(2.5)concentration, which is mainly achieved from the original cities. For the new cities, on the other hand, the expansion significantly increases the local PM_(2.5)concentration. 2) In the long term, the significant influence of urban agglomeration expansion on PM_(2.5)concentration lasts for three years and gradually decreases. A series of robustness tests confirm the applicability of the PSM-DID model.3) Cities with weaker government regulation, a better educated population and higher per capita income present stronger PM_(2.5)reduction effects. 4) Urban agglomeration expansion affects the PM_(2.5)concentration mainly through industrial transfer and population migration, which cause a decrease in the PM_(2.5)concentration in the original cities and an increase in the PM_(2.5)concentration in the new cities.Corresponding policy suggestions are proposed based on the conclusions. 展开更多
关键词 urban agglomeration expansion fine particulate matter(PM_(2.5))concentration quasi-natural experiment propensity scores in difference-in-differences models(PSM-DID) Yangtze river Delta Urban Agglomeration China
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In-situ electrochemical study on the eff ects of Fe(Ⅲ)on kinetics of pyrite acidic pressure oxidation
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作者 Yu Zhang Can Cui +7 位作者 Sen Lin Heping Li Lian Yang Yadian Xie Hailiang Hu Lingyun Zhou Huanjiang Wang Chunyan Li 《Acta Geochimica》 EI CAS CSCD 2024年第4期814-825,共12页
Fe(Ⅲ)has been proved to be a more eff ective oxidant than dissolved oxygen at ambient temperature,however,the role of Fe(Ⅲ)in pyrite acidic pressure oxidation was rarely discussed so far.In this paper,in-situ electr... Fe(Ⅲ)has been proved to be a more eff ective oxidant than dissolved oxygen at ambient temperature,however,the role of Fe(Ⅲ)in pyrite acidic pressure oxidation was rarely discussed so far.In this paper,in-situ electrochemical investigation was performed using a flow-through autoclave system in acidic pressure oxidation environment.The results illustrated that increasing Fe(Ⅲ)concentrations led to raising in redox potential of the solution,and decreased passivation of pyrite caused by deposition of elemental sulfur.Reduction of Fe(Ⅲ)at pyrite surface was a fast reaction with low activation energy,it was only slightly promoted by rising temperatures.While,the oxidation rate of pyrite at all investigated Fe(Ⅲ)concentrations increased obviously with rising temperatures,the anodic reaction was the rate-limiting step in the overall reaction.Activation energy of pyrite oxidation decreased from 47.74 to 28.79 kJ/mol when Fe(Ⅲ)concentration was increased from 0.05 to 0.50 g/L,showing that the reaction kinetics were limited by the rate of electrochemical reaction at low Fe(Ⅲ)concentrations,while,it gradually turned to be diffusion control with increasing Fe(Ⅲ)concentrations. 展开更多
关键词 PYRITE Pressure oxidation Fe(Ⅲ) in-situ electrochemistry Hydrothermal experiment
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Design and Site Experiment of Groyne in Bore Surging Area of Qiantang River
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作者 Xuan, WL Xu, XJ Zhao, YQ 《China Ocean Engineering》 SCIE EI 1997年第4期467-476,共10页
The groyne has been used widely in bank protection and river regulation. The plane layout and structural style of groyne are closely related to the stability of the groyne itself and the effect of bank protection. In ... The groyne has been used widely in bank protection and river regulation. The plane layout and structural style of groyne are closely related to the stability of the groyne itself and the effect of bank protection. In this paper, based on the preliminary summary of the design of bank protection in the bore surging area of Qiantang River, some problems regarding the structure of groyne are pointed out and an improved plan is put forward. Site experiment was carried out combined with an emergency repair. The results of the experiment indicate that the improved project is reliable and successful. 展开更多
关键词 Qiantang river groyne bank protection bore area site experiment
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Experimental and Numerical Studies of the Wave-Induced Responses of a River-to-Sea Ship 被引量:1
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作者 Yiwen Wang Weiguo Wu C.Guedes Soares 《Journal of Marine Science and Application》 CSCD 2018年第3期380-388,共9页
The ship motions and wave-induced loads of a new type of river-to-sea ship are investigated experimentally and numerically. A river-to-sea ship is an unconventional type of container ship characterized by high breadth... The ship motions and wave-induced loads of a new type of river-to-sea ship are investigated experimentally and numerically. A river-to-sea ship is an unconventional type of container ship characterized by high breadth to draft ratio and low length to breadth ratio, which makes it more prone to hydroelasticity than conventional ships of the same size. A segmented model was tested under two loading conditions, namely, ballast and loaded conditions, to determine the vertical motions and wave-induced loads under each condition. Results are compared with numerical simulations in the frequency domain. The wave-induced responses are calculated by a nonlinear time domain code at each time step. The response amplitude operators of vertical ship responses in regular waves are analyzed, and the wave-induced responses are consistent with the experimental results. 展开更多
关键词 river-to-sea SHIP Wave-induced RESPONSES NONLINEAR time DOMAIN simulation experiment
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Analysis on River Bed Changes in Weir Downstream by Real-Scale Experiment
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作者 Dongwoo Ko Joongu Kang 《Engineering(科研)》 2018年第8期505-513,共9页
Flood damage has aggravated recently owing to artificial structures in high flow rare areas such as small rivers, which can lead to secondary damage. In this regard, studies are required to examine the conventional de... Flood damage has aggravated recently owing to artificial structures in high flow rare areas such as small rivers, which can lead to secondary damage. In this regard, studies are required to examine the conventional design criteria formulas to secure the stability of structures such as weirs and drop structures. Although studies on the stability of these structures have been conducted through small-scale experiments, few empirical studies have investigated the hydraulic phenomena occurring near actual artificial structures. In this study, we fabricated real-size models of weir and drop structure at the Andong River Experiment Center and investigated the flow patterns around the structures by applying the particle image velocimetry analysis technique with a flow tracker. We also measured the scour length in the waterspout section when the structures are overflowing, and compared it with the values calculated using the formula. Consequently, as the supply flow increases, the result is different from the value calculated using the formula given in the existing design standard, and it is judged to be inappropriate for a small stream area with high flow rate. Thus, it is necessary to consider the design factors such as energy gradient and the flow amount per unit width into weir and drop structure as well as the existing design factors in designing an apron section for a weir and drop structure. 展开更多
关键词 WEIR Drop Structure Real-Scale experiment river BED SCOUR Characteristic
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Field Scientific Experiment in the Yangtze River Delta Area
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《中国气象科学研究院年报》 1999年第0期13-14,共2页
关键词 Field Scientific experiment in the Yangtze river Delta Area
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Dynamics of Bottom Boundary Layers in the Yellow River Subaqueous Delta Based on Long-Term In-Situ Observations 被引量:8
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作者 ZHU Chaoqi JIA Yonggang +4 位作者 WANG Zhenhao GUO Lei SHAN Hongxian LIU Xiaolei ZHANG Minsheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期369-370,共2页
Objective In geo-marine science,the generalized bottom boundary layer(BBL)represents a layer between sediments and seawater.The BBL plays an important role in geological,geobiochemical,geophysical and geotechnical r... Objective In geo-marine science,the generalized bottom boundary layer(BBL)represents a layer between sediments and seawater.The BBL plays an important role in geological,geobiochemical,geophysical and geotechnical research because it is the connection region of hydrosphere, 展开更多
关键词 Dynamics of Bottom Boundary Layers in the Yellow river Subaqueous Delta Based on Long-Term in-situ Observations
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A full-scale field experiment to study the thermal-deformation process of widening highway embankments in permafrost regions
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作者 ShuangJie Wang Long Jin +3 位作者 Kun Yuan DongGen Chen JinPing Li Yi Song 《Research in Cold and Arid Regions》 CSCD 2021年第2期123-132,共10页
As one of the widely used upgrading way in road engineering, the widening embankment(WE) has suffered evident differential deformation, which is even severer for highway in permafrost regions due to the temperature se... As one of the widely used upgrading way in road engineering, the widening embankment(WE) has suffered evident differential deformation, which is even severer for highway in permafrost regions due to the temperature sensitivity of frozen soil and the heat absorption effect of the asphalt pavement. Given this issue, a full-scale experimental highway of WE was performed along the Qinghai-Tibet Highway(QTH) to investigate the differential deformation features and its developing law. The continuous three years' monitoring data taken from the experimental site, including the ground temperature and the layered deformation of WE and original embankment(OE), were used to analyze the thermal-deformation process. The results indicate that the widening part presented the remarkable thermal disturbance to the existing embankment(EE). The underlying permafrost was in a noteworthy degradation state, embodying the apparent decrease of the permafrost table and the increase of the ground temperature. Correspondingly, the heat disruption induced by widening led to a much higher deformation at the widening side compared to the original embankment, showing a periodic stepwise curve. Specifically, the deformation mainly occurred in the junction of the EE and the widening part, most of which was caused by the thawing consolidation near the original permafrost table. In contrast, the deformation of EE mainly attributed to the compression of the active layer. Furthermore, it was the deformation origination differences that resulted in the differential deformation of WE developed gradually during the monitoring period, the maximum of which reached up to 64 mm. 展开更多
关键词 widening embankment PERMAFROST DEFORMATION in-situ experiment
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An Experiment on Releasing Water from Water Tanks by Xu Youzhen during the Ming Dynasty
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作者 Dai Nianzu Zhang Xumin Yu Yue yuan 《Chinese Annals of History of Science and Technology》 2017年第1期116-120,共5页
In 1453,Xu Youzhen,a scholar-bureaucrat and hydrologist in Ming China,was dispatched to Shandong to find a way to harness the Yellow River.He proposed the opening up of multiple channels to diverge the flood waters.An... In 1453,Xu Youzhen,a scholar-bureaucrat and hydrologist in Ming China,was dispatched to Shandong to find a way to harness the Yellow River.He proposed the opening up of multiple channels to diverge the flood waters.An experiment was conducted to compare the efficiency of releasing water using one large opening with the use of a number of small openings.This experiment proved that opening up multiple channels outperformed the construction of only one,thereby convincing the emperor and officials of the efficacy of this method.Xu’s method for water control proved to be successful in averting a flood that occurred in 1456. 展开更多
关键词 experiment on RELEASING WATER from WATER tanks flood management hydromechanics Xu Youzhen Yellow river
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分支河流体系沉积学工作框架与流程 被引量:2
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作者 张昌民 张祥辉 +4 位作者 王庆 冯文杰 李少华 易雪斐 Adrian JHARTLEY 《岩性油气藏》 CAS CSCD 北大核心 2024年第1期1-13,共13页
基于现有的研究成果和存在的问题,探讨了分支河流体系(DFS)研究中的关键科学问题、主要研究内容、研究方法和工作流程。研究结果表明:①DFS研究中最关键的3个科学问题是明确河网结构和河型演变规律、构建沉积标志和沉积模式、分析其形... 基于现有的研究成果和存在的问题,探讨了分支河流体系(DFS)研究中的关键科学问题、主要研究内容、研究方法和工作流程。研究结果表明:①DFS研究中最关键的3个科学问题是明确河网结构和河型演变规律、构建沉积标志和沉积模式、分析其形成和分布的控制因素。②DFS研究的主要内容包括建设形态沉积学数据库、现代沉积机理研究、分类研究、建立沉积模式、储层建模与储层预测等5个方面。③DFS研究中的关键技术包括基于遥感图像的形态数据采集、形成机理的水槽和模拟实验、河网重构、顶点位置预测与河道分汊点自动生成方法、储层建模知识库平台等。④DFS研究的基本工作流程是先建立形态沉积学数据库,搭建数据库软件平台,在此基础上选择具有代表性的DFS进行现代沉积解剖,然后综合现代沉积调查、露头解剖和模拟实验成果,形成分类体系,总结各类DFS的识别标志和沉积模式,分层次建立储层预测模型,形成沉积结构储层预测模型的建模软件平台,从而预测沉积体系中有利储层的分布。 展开更多
关键词 分支河流体系 河网重构 储层建模 水槽沉积模拟 数据采集 DFS形态沉积学数据库
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尾闾河道形态演变特征的模拟试验研究
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作者 白玉川 孙艳杰 +3 位作者 宋晓龙 徐海珏 吴金森 田源 《水科学进展》 EI CAS CSCD 北大核心 2024年第3期508-520,共13页
尾闾河道是河流与海洋交互的关键地带,对其形态演变研究具有生态环境意义。采用物理试验方法对常见的喇叭状和蜿蜒状(河口左偏与右偏)尾闾河道演变过程进行模拟,研究不同水沙条件下河道演变规律,并以河相系数和相对粗糙度为基准对不同... 尾闾河道是河流与海洋交互的关键地带,对其形态演变研究具有生态环境意义。采用物理试验方法对常见的喇叭状和蜿蜒状(河口左偏与右偏)尾闾河道演变过程进行模拟,研究不同水沙条件下河道演变规律,并以河相系数和相对粗糙度为基准对不同河型稳定性进行评估。试验发现:河道平面形态会经历一个“稳定—微变—强变”阶段;河床平均高程和比降随时间的增加而增大,模型河道上游和河口段变化最大,中游段变化最小;加沙时上游河岸侵蚀、河床淤积,加沙停止后下游与河口段河岸侵蚀大于河床侵蚀,河口分汊、摆动。平面形态不稳定区域:蜿蜒状为下游段,最大与最小河相系数相差6.51倍以上;喇叭状为河口段,最大与最小河相系数相差3.32倍以上。断面形态不稳定区域:左偏蜿蜒状为下游段,最大与最小相对粗糙度相差3倍以上;右偏蜿蜒状为上游段,最大与最小相对粗糙度相差2.03倍以上;喇叭状为下游段,最大与最小相对粗糙度相差4.09倍以上。 展开更多
关键词 河流形态 水沙变化 河相关系 物理试验 尾闾河道-河口
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辫状河三角洲砂体沉积模拟实验研究——以沙湾凹陷三工河组为例
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作者 张春生 刘帆 +3 位作者 斤朕 周行天 林雪莲 施冬 《长江大学学报(自然科学版)》 2024年第1期1-9,共9页
前人通过大量研究认为沙湾凹陷三工河组为辫状河三角洲沉积体系,以缓坡、砂体分布广且延伸距离远为其主要特征而有别于传统的辫状河三角洲沉积体系。为了精细研究沙湾凹陷三工河组的沉积砂体,揭示砂体沉积规律和控制因素,利用沉积模拟... 前人通过大量研究认为沙湾凹陷三工河组为辫状河三角洲沉积体系,以缓坡、砂体分布广且延伸距离远为其主要特征而有别于传统的辫状河三角洲沉积体系。为了精细研究沙湾凹陷三工河组的沉积砂体,揭示砂体沉积规律和控制因素,利用沉积模拟实验平台开展沉积模拟实验。模拟结果表明:沙湾凹陷三工河组辫状河三角洲砂体主要存在纵向伸长、纵横向平衡及横向展宽三个阶段,沉积砂体发育存在平衡点;砂体内部垂向联通性及侧向连续性与物源距离关系密切,并将砂体叠置连通性关系划分为9类;在特定时期和条件下会形成无侵蚀面的暂时性新型河道;砂体发育主要受控于地形坡度、水动力条件、物源供给、湖平面变化及构造强度5种因素,各因素之间存在相互制约关系。 展开更多
关键词 沉积模拟 沉积特征 辫状河三角洲 三工河组 沙湾凹陷
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燃料包壳表面沉积层对汽化核心密度影响的实验研究
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作者 蔡杰进 胡致平 邓日宁 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第4期790-800,共11页
燃料包壳表面沉积层在压水堆常规运行中形成,其对包壳沸腾传热的影响尚不清楚。为了探索包壳表面沉积层对汽化核心密度的影响规律,本文基于常压下的流动沸腾可视化实验台架,以锆-4合金为基板,采用逐层沉积的方法形成不同厚度的SiO_(2)... 燃料包壳表面沉积层在压水堆常规运行中形成,其对包壳沸腾传热的影响尚不清楚。为了探索包壳表面沉积层对汽化核心密度的影响规律,本文基于常压下的流动沸腾可视化实验台架,以锆-4合金为基板,采用逐层沉积的方法形成不同厚度的SiO_(2)沉积层,通过开展流动沸腾实验对比不同沉积层厚度下的汽化核心密度差异。研究发现,SiO_(2)沉积表面与未沉积表面相比汽化核心密度增大,Koncar模型可较好地预测本实验工况条件下的汽化核心密度。 展开更多
关键词 流动沸腾实验 表面沉积层 汽化核心密度
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塔里木河植被根系对河岸冲刷特性影响的现场试验
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作者 宗全利 张禹洋 +3 位作者 唐瑞泽 汤骅 刘华利 李琳 《水科学进展》 EI CAS CSCD 北大核心 2024年第2期232-243,共12页
为研究现场条件下植被根系对河岸冲刷特性的定量影响,设计制作了冲刷试验装置,在塔里木河干流上游选取了4个典型位置,开展了胡杨、芦苇、红柳和骆驼刺4种典型根系的18组土体起动切应力和冲刷系数现场试验。试验结果表明:①起动切应力随... 为研究现场条件下植被根系对河岸冲刷特性的定量影响,设计制作了冲刷试验装置,在塔里木河干流上游选取了4个典型位置,开展了胡杨、芦苇、红柳和骆驼刺4种典型根系的18组土体起动切应力和冲刷系数现场试验。试验结果表明:①起动切应力随根系含量增大基本呈幂函数关系增大,且相同根系含量对应起动切应力红柳最大,胡杨和骆驼刺次之,芦苇最小;分析了单位根系含量变化对起动切应力的影响效果,其顺序为骆驼刺>胡杨>红柳>芦苇。②建立了起动切应力与根系体积密度的定量关系式;根系的存在可以减小土体冲刷系数,其值随根系含量增大基本呈幂函数关系减小,且单位根系含量增加对冲刷系数的减小效果次序为骆驼刺>胡杨>红柳>芦苇。③建立了有、无根系影响的冲刷系数与起动切应力幂函数关系式,并与已有试验结果进行了对比分析;本文试验结果与现有研究结果规律一致,但对应的系数和指数均有所差异。研究成果能为塔里木河植被护坡和河岸冲刷过程计算提供参考依据。 展开更多
关键词 冲刷特性 起动切应力 冲刷系数 植被根系 现场试验 塔里木河
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黄河三角洲盐沼湿地螃蟹洞穴形态结构对土壤水盐运移过程的影响
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作者 解璐萌 查玟琦 +4 位作者 车纯广 李游蕊 李纪尧 刘佳凯 张振明 《生态与农村环境学报》 CAS CSCD 北大核心 2024年第6期831-839,共9页
明晰潮汐驱动下螃蟹洞穴对盐沼湿地水盐运移过程的扰动效应,对基于生态过程的黄河三角洲盐沼湿地保护与修复具有重要的理论及现实意义。研究结合野外调查和室内水槽模拟实验,探究潮间带螃蟹洞穴形态与分布特征,分析了潮汐作用下不同螃... 明晰潮汐驱动下螃蟹洞穴对盐沼湿地水盐运移过程的扰动效应,对基于生态过程的黄河三角洲盐沼湿地保护与修复具有重要的理论及现实意义。研究结合野外调查和室内水槽模拟实验,探究潮间带螃蟹洞穴形态与分布特征,分析了潮汐作用下不同螃蟹洞穴形态对水盐运移过程的影响。结果表明:(1)潮汐影响下,黄河三角洲潮间带螃蟹洞穴空间分布密度有差异,3条潮沟洞穴密度分别为(15.50±4.65)、(12.90±2.69)和(6.60±2.76)个·(0.25 m^(2))^(-1);(2)对螃蟹洞穴树脂模型进行简化归类,发现其主要形态结构为I型、L型、S型、X型、Y型,以上5种形态在获得的42个螃蟹洞穴中占比高达85.7%;(3)不同螃蟹洞穴形态在潮汐作用下土壤含水量变化趋势没有明显差异,而电导率随高潮与低潮呈现不同的升高与降低过程;(4)潮汐影响下,空白实验组潮汐水入渗量、孔隙水排泄量均显著低于有螃蟹洞穴的实验组,孔隙水排泄主要集中在水位下降时段,而L型洞穴因具有一定的储水能力,使更多的孔隙水在稳定时段排泄。(5)不同螃蟹洞穴形态对土壤盐排泄量有显著影响,S2、X和I组盐排泄量最高,空白组最低,仅为(0.403±0.003)g·d^(-1)。研究结果从水文学角度揭示了螃蟹洞穴的生态功能,将为后续的滨海湿地生态水文过程研究提供参考。 展开更多
关键词 黄河三角洲 盐沼湿地 螃蟹洞穴 水盐运移过程 模拟实验
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不平衡输沙条件下河道断面形态调整规律试验研究
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作者 杨芬娇 韩沙沙 +1 位作者 赵连军 常奥 《人民黄河》 CAS 北大核心 2024年第9期127-131,共5页
21世纪以来,受气候变化与人类活动共同影响,进入黄河下游河道的水沙条件发生显著变化,下游河道长期处于不平衡输沙状态,横断面形态调整剧烈,直接影响河势稳定,威胁下游防洪安全。基于2001—2021年黄河下游白鹤镇—高村河段实测断面资料... 21世纪以来,受气候变化与人类活动共同影响,进入黄河下游河道的水沙条件发生显著变化,下游河道长期处于不平衡输沙状态,横断面形态调整剧烈,直接影响河势稳定,威胁下游防洪安全。基于2001—2021年黄河下游白鹤镇—高村河段实测断面资料,在分析原型河道横断面形态参数演变特征的基础上,选取黑岗口—柳园口河段开展物理模型试验,以定量揭示不平衡输沙条件下横断面形态调整规律。原型实测资料分析发现,相对于黄河下游其他河段,花园口—夹河滩河段断面形态变化相对较大。选择花园口—夹河滩河段中典型河段为原型,采用水平比尺600、垂直比尺60构建物理模型,保持相同的初始河道边界条件,开展了2000、3000、4000、5000 m^(3)/s四级流量,不同进口含沙量条件下断面形态调整试验。试验结果表明,各测验断面基本呈现进口含沙量较小时主槽冲刷、面积增大、河相系数减小,进口含沙量较大时主槽淤积、面积减小、河相系数增大的规律。对比原型资料与试验数据发现,不平衡输沙条件下,河段尺度的断面形态参数与来沙系数相关性较好,其中主槽面积与来沙系数成指数负相关,河相系数与来沙系数成二次函数关系。 展开更多
关键词 横断面 形态调整 不平衡输沙 物理模型试验 黄河下游
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初探水电工程建设征地移民安置竣工验收主要问题的处理措施--以云南省金沙江中游大型水电工程为例
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作者 郭瑾瑜 王奎 文良友 《水力发电》 CAS 2024年第6期12-16,共5页
依托云南省已实施完成的金沙江中游6座大型水电站工程建设征地移民安置竣工验收工作实践情况,从验收依据、验收内容以及工作组织管理等方面分析制约水电工程建设征地移民安置竣工验收的主要问题,提出高位推动、调整规划、资金保障、工... 依托云南省已实施完成的金沙江中游6座大型水电站工程建设征地移民安置竣工验收工作实践情况,从验收依据、验收内容以及工作组织管理等方面分析制约水电工程建设征地移民安置竣工验收的主要问题,提出高位推动、调整规划、资金保障、工作大纲、技术支撑、资金清理审计与档案专项验收等工作的成功经验与对策措施。 展开更多
关键词 水电工程 移民安置竣工验收 经验与对策 金沙江中游
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砂岩储层中凝灰质溶蚀效应的物理模拟实验研究——以珠江口盆地惠州—陆丰地区古近系文昌组为例
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作者 李晓艳 彭光荣 +4 位作者 丁琳 远光辉 张琴 吴琼玲 靳子濠 《石油实验地质》 CAS CSCD 北大核心 2024年第1期173-182,共10页
为认识埋藏过程中酸性流体对碎屑岩储层中凝灰质的溶蚀改造效应及控制因素,选取珠江口盆地珠一坳陷惠州—陆丰地区古近系文昌组凝灰质砂岩储层,设计开展了岩心尺度的流体—岩石相互作用模拟实验。通过显微镜下观察、流体成分分析、物性... 为认识埋藏过程中酸性流体对碎屑岩储层中凝灰质的溶蚀改造效应及控制因素,选取珠江口盆地珠一坳陷惠州—陆丰地区古近系文昌组凝灰质砂岩储层,设计开展了岩心尺度的流体—岩石相互作用模拟实验。通过显微镜下观察、流体成分分析、物性表征等方法,对比分析了实验前后不同流体流速、不同凝灰质含量条件下砂岩储层的溶蚀作用和物性响应特征。结果表明,酸性流体环境中凝灰质溶蚀现象普遍,但不同实验条件下,凝灰质溶蚀强度及储层物性响应不同:成岩体系的开放性与封闭性决定凝灰质的溶蚀作用强弱。相同岩石和相同酸性流体条件下,高流速开放体系中凝灰质溶蚀量高于封闭体系,且低流速相对封闭体系中溶蚀产物趋于沉淀,溶蚀作用增孔效应有限。凝灰质含量显著影响溶蚀效应,富凝灰质砂岩中溶蚀作用有限,含凝灰质砂岩和贫凝灰质砂岩能够溶蚀增孔,且含凝灰质砂岩的溶蚀增孔效率更高。凝灰质含量相对中等—较低的储层中,中浅层埋藏阶段的开放成岩流体体系最有利于粒间凝灰质溶孔的发育。经历晚期酸性流体溶蚀改造后,较易形成次生溶蚀型优质储层,这一认识有助于不同地区的溶蚀型储层甜点预测。 展开更多
关键词 凝灰质溶蚀蚀变 成岩体系 溶蚀模拟实验 惠州—陆丰地区 珠一坳陷 珠江口盆地
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引黄滴灌不同含沙率对灌水器堵塞影响和试验研究
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作者 相扬帆 岑睿 +2 位作者 吴文勇 胡雅琪 许健 《水资源与水工程学报》 CSCD 北大核心 2024年第4期206-211,224,共7页
灌水器堵塞是影响黄河水滴灌灌水质量的关键因素。对8种不同灌水器与1‰(1 kg/t)、2‰(2 kg/t)、4‰(4 kg/t)3种含沙率进行模拟试验,重点研究了引黄滴灌不同类型滴灌灌水器的流量变化规律和堵塞效应。试验结果表明:灌水器的流量衰减率... 灌水器堵塞是影响黄河水滴灌灌水质量的关键因素。对8种不同灌水器与1‰(1 kg/t)、2‰(2 kg/t)、4‰(4 kg/t)3种含沙率进行模拟试验,重点研究了引黄滴灌不同类型滴灌灌水器的流量变化规律和堵塞效应。试验结果表明:灌水器的流量衰减率随着灌水历时的增加而增大,灌水300 h后衰减率整体达到43%~72%;流量衰减率随着含沙率的增加而增大,低泥沙含量时(1‰),75%的灌水器呈现中度堵塞情况,高泥沙含量时(4‰),100%的灌水器呈现重度堵塞。灌水器N-1.6与N-2.0B在3种不同含沙率下的灌水均匀度均达到80%以上,可以满足作物的灌溉需求。灌水器的流量衰减与灌水器的流道长度呈正相关,随着流道长度的增加,灌水器抗堵塞性能降低,流量衰减率增大。流道内沉积泥沙的中值粒径与灌水器设计流速呈负相关,随着设计流速的增加而减小。灌水器流道内0~30μm粒径的沉积泥沙体积比随含沙率的增加而不断降低。研究成果可为解决引黄滴灌灌水器堵塞问题提供参考。 展开更多
关键词 引黄滴灌 灌水器堵塞 含沙率 流量衰减率 灌水均匀度 模型试验
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