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Effects of Serum Concentration, Synchronization Time and Confluence on the Cell-Cycle Synchronization Efficiency of Goat Fibroblasts
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作者 Van Khanh Nguyen Huong Thu Thi Vu +4 位作者 Au Thi Hoang Yen Kim Thi Pham Giang Thi Thanh Nhan Hung Phu Lai Lan Doan Pham 《Open Journal of Animal Sciences》 2024年第3期194-203,共10页
This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference... This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference in the percentage of nucleated fibroblasts in the G0/G1 stage between serum concentrations of 0.3% and 0.4% (83.89% and 82.69%, respectively, P > 0.05) as well as between serum concentrations of 0.2% and 0.5% (76.95% and 75.46%, respectively, P > 0.05). The percentage of nucleated fibroblasts in the G0/G1 stage was highest at the concentration of 0.3% and lowest in the control group (83.89% vs. 62.67%, P 0.05). The beneficial effect of high confluence was confirmed by the large percentage of nucleated fibroblasts at the G0/G1 stage. The 60% confluency was significantly lower than the 80% and 100% confluency (73.44%, 86.63%, and 87.17%, respectively, P < 0.05). The results indicate that the goat fibroblast cycle synchronization is the most effective at the serum concentration of 0.3%, 72 hours of synchronization and 100% confluency. 展开更多
关键词 Goat Fibroblast Cycle Synchronisation Serum Concentration Synchronization Time confluence
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Pollution control of outfall of rainwater-sewage confluence in old town
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作者 黄勇强 史凯 +1 位作者 朱艳 刘荣平 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期230-233,共4页
In order to improve water quality of middle ancient canal in Zhenjiang city a pollution control project was carried out.The research area is the middle catchment area of the ancient canal river system in the old town ... In order to improve water quality of middle ancient canal in Zhenjiang city a pollution control project was carried out.The research area is the middle catchment area of the ancient canal river system in the old town of Zhenjiang. The specific research object is the runoff of the outfall of rainwater-sewage confluence in the area. On the basis of detecting and analyzing the water yield and water quality of the runoff of rainwater-sewage confluence a combined technology which contains four independent continuous processes for lowering pollution load was developed and system equipment was established and put into operation. The processing effects of the project were monitored and analyzed.The results show that the pollution control project of outfall runoff is efficient which decreases the pollution load including chemical oxygen demand COD total phosphorus TP suspended solids SS and ammonia-nitrogen NH3-N .As a result the water environment of the ancient canal is protected. 展开更多
关键词 urban rainwater confluence of rainwater and sewage outfall rainwater runoff pollution load processing equipment
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Influence of bed elevation discordance on flow patterns and head losses in an open-channel confluence 被引量:4
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作者 Pedro Xavier Ramos Laurent Schindfessel +1 位作者 Joao Pedro Pego Tom De Mulder 《Water Science and Engineering》 EI CAS CSCD 2019年第3期235-243,共9页
Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is common.Studies of schematized co... Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is common.Studies of schematized confluences with a step at the interface between the tributary and the main channel bed reveal that bed elevation discordance is an important additional control for the confluence hydrodynamics.This study aimed to improve understanding of the influence of bed elevation discordance on the flow patterns and head losses in a right-angled confluence of an open channel with rectangular cross-sections.A large eddy simulation (LES)-based numerical model was set up and validated with experiments by others.Four configurations with different bed discordance ratios were investigated.The results confirm that, with increasing bed elevation discordance, the tributary streamlines at the confluence interface deviate less from the geometrical confluence angle, the extent of the recirculation zone (RZ) gets smaller, the ratio of the water depth upstream to that downstream of the confluence decreases, and the water level depression reduces.The bed elevation discordance also leads to the development of a large-scale structure in the lee of the step.Despite the appearance of the large-scale structure, the reduced extent of the RZ and associated changes in flow deflection/contraction reduce total head losses experienced by the main channel with an increase of the bed discordance ratio.It turns out that bed elevation discordance converts the lateral momentum from the tributary to streamwise momentum in the main channel more efficiently. 展开更多
关键词 Open channel confluence BED ELEVATION DISCORDANCE Three-dimensional numerical modelling Large EDDY simulation Recirculation ZONE
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Confluence and cold shut computation based on time field in casting simulation 被引量:4
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作者 Yong-shuai Feng Dun-ming Liao Tao Chen 《China Foundry》 SCIE CAS 2021年第2期101-109,共9页
Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes.During the casting filling process,many filling-related defects form easily at the confluences of l... Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes.During the casting filling process,many filling-related defects form easily at the confluences of liquid metal streams.The main filling-related defects are cold shut defects.To calculate the positions of casting defects,the characteristics of liquid metal confluences were analyzed.The flow front of liquid metal was captured by the volume-of-fluid algorithm to obtain a time field,which was used to calculate the time derivatives of the liquid front position and the confluences of liquid metal streams.To distinguish small confluences from the main confluences,the concept of confluent scale was developed,which was used to filter the small confluences based on a threshold.The calculation process was demonstrated through the post-processing of numerical simulation.A "W" shaped casting and a steering wheel casting were calculated to validate the accuracy of the method developed in this study.The positions of cold shut defects were predicted by calculating the confluences of liquid metal streams.The method was proved to be practical by comparing the calculation results with the positions of cold shut defects in an end cover casting.The computation of confluences and cold shut defects can improve the analysis efficiency and provide assurance for the optimization of a casting process plan. 展开更多
关键词 numerical simulation casting defects flow front time field confluence cold shut
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Managing injuries of hepatic duct confluence variants after major hepatobiliary surgery:An algorithmic approach 被引量:4
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作者 Georgios Fragulidis Athanasios Marinis +5 位作者 Andreas Polydorou Christos Konstantinidis Georgios Anastasopoulos John Contis Dionysios Voros Vassilios Smyrniotis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第19期3049-3053,共5页
AIM:To investigate injuries of anatomy variants of hepatic duct confluence during hepatobiliary surgery and their impact on morbidity and mortality of these procedures. An algorithmic approach for the management of th... AIM:To investigate injuries of anatomy variants of hepatic duct confluence during hepatobiliary surgery and their impact on morbidity and mortality of these procedures. An algorithmic approach for the management of these injuries is proposed. METHODS:During a 6-year period 234 patients who had undergone major hepatobiliary surgery were retrospectively reviewed in order to study postoperative bile leakage. Diagnostic workup included endoscopic and magnetic retrograde cholangiopancreatography (E/MRCP), scintigraphy and fistulography. RESULTS:Thirty (12.8%) patients who developed postoperative bile leaks were identified. Endoscopic stenting and percutaneous drainage were successful in 23 patients with bile leaks from the liver cut surface. In the rest seven patients with injuries of hepatic duct confluence, biliary variations were recognized and a stepwise therapeutic approach was considered. Conservative management was successful only in 2 patients. Volume of the liver remnant and functional liver reserve as well as local sepsis were used as criteria for either resection of the corresponding liver segment or construction of a biliary-enteric anastomosis. Two deaths occurred in this group of patients with hepatic duct confluence variants (mortality rate 28.5%). CONCLUSION:Management of major biliary fistulaethat are disconnected from the mainstream of the biliary tree and related to injury of variants of the hepatic duct confluence is extremely challenging. These patients have a grave prognosis and an early surgical procedure has to be considered. 展开更多
关键词 Biliary aberrations Bile duct injury Postope-rative bile leakage Hepatic duct confluence HEPATECTOMY
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An Empirical Formula for Suspended Sediment Delivery Ratio of Main River after Confluence of Debris flow 被引量:1
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作者 ZHANG Jin-shan CUI Peng 《Journal of Mountain Science》 SCIE CSCD 2013年第2期326-336,共11页
In order to calculate the suspended sediment discharge of the flood debris flows into the main river,a small scale flume test was designed to simulate the process of confluence of Jiangjia Ravine and Xiangjiang River ... In order to calculate the suspended sediment discharge of the flood debris flows into the main river,a small scale flume test was designed to simulate the process of confluence of Jiangjia Ravine and Xiangjiang River in Yunnan province,China.By test observation and data analysis,suspended sediment discharge of Debris flow after its entry into the main river was found to have a close relation with the bulk density,the confluence angle of the Debris flow and the main river,the ratio between per unit width discharge of Debris flow and main river.Based on the measured and simulated results,and statistical analysis,an empirical formula was proposed for the suspended SDR(Sediment Delivery Ratio) of the main river after the confluence of Debris flow.Compared with the observed results of Debris flow in 2009,the error between the data calculated by the empirical formula and the monitored data is only about 10%. 展开更多
关键词 Debris flow confluence SuspendedSediment Delivery Ratio (SDR) Jiangjia Ravine Xiaojiang River Model
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Modelling of debris-flow susceptibility and propagation: a case study from Northwest Himalaya 被引量:2
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作者 Hamza DAUD Javed Iqbal TANOLI +5 位作者 Sardar Muhammad ASIF Muhammad QASIM Muhammad ALI Junaid KHAN Zahid Imran BHATTI Ishtiaq Ahmad Khan JADOON 《Journal of Mountain Science》 SCIE CSCD 2024年第1期200-217,共18页
The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study are... The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure. 展开更多
关键词 North Pakistan Debris flow Flow-R Propagation Susceptibility mapping debris-flow inventory Weighted Overlay Method
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Intermittent portal triad clamping in resection of liver tumors involving the hepatocaval confluence
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《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第2期276-280,共5页
Objective: To review our experience in and the re-sults of resecting liver tumors involving the hepatoca-val confluence under intermittent portal triad clam-ping (PTC).Methods: Sixty-eight consecutive patients with li... Objective: To review our experience in and the re-sults of resecting liver tumors involving the hepatoca-val confluence under intermittent portal triad clam-ping (PTC).Methods: Sixty-eight consecutive patients with livertumors involving the hepatocaval confluence under-went hepatectomies with liver parenchymal transec-tions under intermittent PTC.Results: All the tumors were successfully resected un-der PTC, except for one in which the infrahepatic in-ferior vena cava was concomitantly occluded in addi-tion to PTC. There was neither operative death noruncontrollable massive bleeding or air embolism oc-curred in our patients. The bleedings from the mainand short hepatic veins and right adrenal veins wereproperly managed during the operation, with a meanintraoperative blood loss of 1400 ml. Of the 68tumors resected, 65 were hepatocellular carcinomas(HCC). Their 1-, 2-, 3- and 4-year suvival rateswere 64.11%, 52. 82%, 44.90% and 36.98%, re-spectively, and the patients with HCC with capsulessurvived significantly longer than those with HCCwithout capsules.Conclusions: The liver tumors involving the hepato-caval confluence could be safely resected simply un-der PTC, without routine use of total hepatic vascu-lar exclusion. As for HCCs in this area, the tumorwith capsule is a better indicator for surgical resec-tion than that without capsule. 展开更多
关键词 HEPATECTOMY hepatocval confluence PORTAL TRIAD CLAMPING hepatic vascular EXCLUSION liver neoplasmas
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Liver tumors invading the hepatocaval confluence:treatment improvements still not completed
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作者 Isidoro Di Carlo 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2016年第6期570-571,共2页
Also if rarely, hepatocellular carcinoma, cholangiocarcinoma, and metastatic carcinoma can invade the retrohepatic portion of the inferior vena cava (IVC), because of the proximity of this vessel to the liver.
关键词 IVC Liver tumors invading the hepatocaval confluence
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Quantifying the impact of earthquakes and geological factors on spatial heterogeneity of debris-flow prone areas:A case study in the Hengduan Mountains
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作者 HU Xudong SHEN Yitong +6 位作者 HU Kaiheng XU Wennian LIU Daxiang HE Songtang GAO Jiazhen WEI Li LIU Shuang 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1522-1533,共12页
Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significan... Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the Hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debrisflow prone areas. Results showed that the application of GIS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debrisflow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m-2500 m elevation difference, 25°-30° average slope, and 0.13-0.15 land use index is the most favorable conditions for debris-flow occurrence;The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies. 展开更多
关键词 debris-flow prone areas causal factors GIS-based method spatial heterogeneity Hengduan Mountains
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明渠交汇口水动力及掺混特性研究进展
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作者 曾诚 周婧 +4 位作者 李凯 付毅成 周婕 蔡雷 王玲玲 《水利水电科技进展》 北大核心 2025年第1期10-17,共8页
针对明渠交汇区域内水流结构的复杂情况,从明渠交汇口汇流比、交汇角度、床面高差和其他影响因素的角度,综述了明渠交汇口分离区、剪切层、二次环流等很多特有的水动力及掺混特性的研究进展,梳理了物理模型试验、数值模拟研究和实地观... 针对明渠交汇区域内水流结构的复杂情况,从明渠交汇口汇流比、交汇角度、床面高差和其他影响因素的角度,综述了明渠交汇口分离区、剪切层、二次环流等很多特有的水动力及掺混特性的研究进展,梳理了物理模型试验、数值模拟研究和实地观测成果,总结了水动力及掺混特性的研究现状。基于目前存在的主要问题,未来应重点研究人工智能算法的应用,植被、密度差、潜流带对掺混特性的影响以及挟沙水流交汇问题中的冲刷淤积影响。 展开更多
关键词 明渠交汇口 水动力 掺混 影响因素
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1993—2022年间黑潮延伸体及黑潮与亲潮交汇区水文特性年代际至长期变化
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作者 张俊 程灵巧 +1 位作者 魏永亮 刘必林 《海洋科学进展》 北大核心 2025年第1期76-92,共17页
大尺度大气强迫驱动了黑潮延伸体(Kuroshio Extension,KE)系统的年代际至长期变化。其中,研究长期变化趋势对认识KE系统如何响应全球气候变化具有重要意义。本文基于1993—2022年期间的卫星遥感数据,对比分析了2010年前后两个时期KE系... 大尺度大气强迫驱动了黑潮延伸体(Kuroshio Extension,KE)系统的年代际至长期变化。其中,研究长期变化趋势对认识KE系统如何响应全球气候变化具有重要意义。本文基于1993—2022年期间的卫星遥感数据,对比分析了2010年前后两个时期KE系统和黑潮-亲潮交汇区(Kuroshi-Oyashio Confluence,KOC)区域的热、动力特征及中尺度涡旋变化,同时结合横跨北太平洋的海面风场及海表面异常信号讨论了北太平洋大尺度海表动力异常与KE-KOC区域变化之间的对应关系。结果表明,2010年之前,KE系统主要由两个时间跨度长、强度较强的不稳定态主导。不稳定时期,更多的反气旋式涡旋向北分离,将KE区域的海表信号传递给KOC区域。在2010年之后,KE系统的长期变化特征占主导地位,主要表现为KE流轴整体北移,对应海表面温度异常(Sea Surface Temperature Anomaly,SSTA)和海表面高度异常(Sea Level Anomaly,SLA)整体升高,KE上游两个曲流附近的海表地转流东向分量变平缓、南向分量减弱。这期间KOC区域的SSTA和SLA也存在类似变化。2010年之后在北太平洋中纬度负的风应力旋度异常驱使下,太平洋十年涛动(Pacific Decadal Oscillation,PDO)的负相位开始占主导,对应北太平洋中部海表面高度和海表面温度(Sea Surface Temperature,SST)出现显著正异常。该海洋信号传递到西北太平洋,主导KE-KOC区域的水文特性变化。2010年往后的差异性长期变化仍需在更长时间尺度上进行验证,这也为未来的黑潮延伸体区域模型预测提供了有效参考。 展开更多
关键词 黑潮延伸体 黑潮-亲潮交汇区 水文特性 年代际变化 长期变化
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拥有兄弟姐妹如何影响青少年的认知能力和主观幸福感?
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作者 梁文艳 何茜 《华东师范大学学报(教育科学版)》 北大核心 2025年第1期81-95,共15页
本研究对兄弟姐妹数量与青少年成长之间的关系进行了全面的理论探讨,并利用2010—2018年中国家庭追踪调查数据,为识别兄弟姐妹对青少年认知能力和主观幸福感的影响提供了微观证据。实证研究结果表明:拥有1个兄弟姐妹对青少年的主观幸福... 本研究对兄弟姐妹数量与青少年成长之间的关系进行了全面的理论探讨,并利用2010—2018年中国家庭追踪调查数据,为识别兄弟姐妹对青少年认知能力和主观幸福感的影响提供了微观证据。实证研究结果表明:拥有1个兄弟姐妹对青少年的主观幸福感有积极影响,这种影响效应随年龄增长而加强,并且在成年后依旧保持稳定;拥有兄弟姐妹可能对青少年的数学类认知能力产生负向影响,这种影响主要体现在较低学段样本中,并随年龄增长逐渐消失。本研究为父母制定生育决策时更有效地开展成本收益分析提供了支持,也为缓解养育焦虑、完善生育政策以及促进人口可持续发展提供了政策启示。 展开更多
关键词 资源稀释 群聚理论 同胞互动模型 认知能力 主观幸福感
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引江济淮干支交汇处通航水流条件分析
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作者 郭亚龙 孙佳 +2 位作者 曾易 陈曾友 庄宁 《中国港湾建设》 2025年第1期16-22,共7页
以引江济淮江淮沟通段、菜子湖段支流入汇为实例,针对其典型交汇段存在的复杂通航水流条件,运用数值模拟的方法,对比所选汇流口工况下交汇水域的横流分布,同时分析河道横比降,以此评价河段通航水流条件的安全性。根据研究结果:最大横流... 以引江济淮江淮沟通段、菜子湖段支流入汇为实例,针对其典型交汇段存在的复杂通航水流条件,运用数值模拟的方法,对比所选汇流口工况下交汇水域的横流分布,同时分析河道横比降,以此评价河段通航水流条件的安全性。根据研究结果:最大横流区位于汇流口靠近下游位置,横流值成放射状向对岸递减,且在此处横比降最大,此区域应视为通航最危险区域。随着汇流比、支流入汇角的增大,交汇区域横流值、横比降峰值递增。当支流入汇角为30°、汇流比为0.7和支流入汇角90°、汇流比为0.2时,河道通航环境相对安全,其余工况均存在不同程度的通航风险。研究结果可为江淮沟通段、菜子湖段其他交汇水域的通航安全评价提供一定的技术支撑。 展开更多
关键词 支流入汇 横向流速 通航安全 横比降 数值模拟
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交汇区的交汇角和汇流比对微塑料运移的影响
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作者 曹力玮 谌昱含 +3 位作者 高玮峥 李德鸿 李小龙 李昇 《中国环境科学》 北大核心 2025年第1期265-277,共13页
本文建立了适用于交汇区的三维水动力-微塑料运动耦合模型,基于CFD-DEM耦合方法模拟,探究了不同交汇角、不同汇流比条件下微塑料的水动力输运机制与赋存特性.结果表明:干支流交汇区中的低流速区(分离区、停滞区、分离区下游)将发展为微... 本文建立了适用于交汇区的三维水动力-微塑料运动耦合模型,基于CFD-DEM耦合方法模拟,探究了不同交汇角、不同汇流比条件下微塑料的水动力输运机制与赋存特性.结果表明:干支流交汇区中的低流速区(分离区、停滞区、分离区下游)将发展为微塑料的富集区域;微塑料主要受位于流动分离区中漩涡的影响,从主流右岸进入漩涡区,逐渐形成椭圆形富集带;流动分离区中心微塑料丰度与交汇角呈线性正相关关系;流动分离区中心微塑料丰度与干支流汇流比呈线性负相关关系,R^(2)=0.9007.研究结果将丰富干支流交汇区微塑料运动的基础理论,为精确化防治微塑料污染提供理论依据. 展开更多
关键词 微塑料 交汇区 CFD-DEM 交汇角 汇流比 富集区域
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Comparison of satellite-estimated and model-forecasted rainfall data during a deadly debris-flow event in Zhouqu, Northwest China 被引量:9
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作者 WANG Jun WANG Hui-Jun HONG Yang 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第2期139-145,共7页
The data of several rainfall products, including those estimated from satellite measurements and those forecasted via numerical weather modeling, for a severe debris-flow event in Zhouqu, Northwest China, are compared... The data of several rainfall products, including those estimated from satellite measurements and those forecasted via numerical weather modeling, for a severe debris-flow event in Zhouqu, Northwest China, are compared and analyzed in this paper. The satellite products, including CPC MORPHing technique(CMORPH), TMPA-RT, and PERSIANN are all near-real-time retrieved with high temporal and spatial resolutions. The numerical weather model used in this paper for precipitation forecasting is WRF. The results show that all three satellite products can basically reproduce the rainfall pattern, distribution, timing, scale, and extreme values of the event, compared with gauge data. Their temporal and spatial correlation coefficients with gauge data are as high as about 0.6, which is statistically significant at 0.01 level. The performance of the forecasted results modeled with different spatial resolutions are not as good as the satellite-estimated results, although their correlation coefficients are still statistically significant at 0.05 level. From the total rainfall and extreme value time series for the domain, it is clear that, from the grid-to-grid perspective, the passive microwave-based CMORPH and TRMM products are more accurate than the infrared-based PERSIANN, while PERSIANN performs very well from the general point of view, especially when considering the whole domain or the whole convective precipitation system. The forecasted data — especially the highest resolution model domain data — are able to represent the total or mean precipitation very well in the research domain, while for extreme values the errors are large. This study suggests that satellite-retrieved and model-forecasted rainfall data are a useful complement to gauge data, especially for areas without gauge stations and areas not covered by weather radars. 展开更多
关键词 RAINFALL remote sensing numerical weather model Zhouqu debris-flow event high-resolution data
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Numerical Investigation on the Initiation Mechanism of Debris-Flow under Rainfall 被引量:4
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作者 LU Xiaobing YE Tianli +2 位作者 CUI Peng HU Kaiheng CHEN Xiaoqing 《Journal of Mountain Science》 SCIE CSCD 2011年第4期619-628,共10页
Rainfall is an important factor to trigger the debris flow.Numerical simulation on the responses of slopes and the initiation of debris flow under rainfall was processed by using the software FLAC2D based on the soil ... Rainfall is an important factor to trigger the debris flow.Numerical simulation on the responses of slopes and the initiation of debris flow under rainfall was processed by using the software FLAC2D based on the soil parameters in Weijia Gully,Beichuan County,Sichuan Province,China.The effects of the slope angle,rainfall intensity,soil parameters on the developments of the stress and pore pressure and deformation of the slope were studied.It indicates that large displacements of the slope are mainly located near the slope toe.With the increase of the rainfall intensity the stability of the slope decreases and so the debris-flow is easy to occur. 展开更多
关键词 debris-flow Initiation mechanism RAINFALL Numerical simulation
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Debris-flow of Zelongnong Ravine in Tibet 被引量:4
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作者 ZHANG Jinshan SHEN Xingju 《Journal of Mountain Science》 SCIE CSCD 2011年第4期535-543,共9页
Zelongnong Ravine,a branch ravine of Brahmaputra,is an old large glacier debris-flow ravine.Debris-flows with medium and/or small scales occur almost every year;multiple super debris-flows have also broken out in hist... Zelongnong Ravine,a branch ravine of Brahmaputra,is an old large glacier debris-flow ravine.Debris-flows with medium and/or small scales occur almost every year;multiple super debris-flows have also broken out in history,and have caused destructive disaster to local residents at the mouth of ravine and blocked Brahmaputra.The huge altitude difference and the steep slope of the Zelongnong Ravine provide predominant energy conditions for the debris-flow.The drainage basin is located in the fast uplifted area,where the complicated geologic structure,the cracked rock,and the frequent earthquake make the rocks experience strong weathering,thus plenty of granular materials are available for the formation of debris-flows.Although this region is located in the rain shadow area,the precipitation is concentrated and most is with high intensity.Also,the strong glacier activity provides water source for debris-flow.According to literature reviews,most debris-flows in the ravine are induced by rainstorms,and their scales are relatively small.However,when the melted water is overlaid,the large scale debris-flows may occur.Parametric calculation such as the flow velocity and the runoff is conducted according to the monitoring data.The result shows that large debris-flows can be aroused when the rainstorm and the melted water are combined well,but the possibility of blocking off Brahmaputra is rare.The occurrence of the super debris-flows is closely related to the intense glacier activity(e.g.,glaciersurge).They often result in destructive disasters and are hard to be prevented and cured by engineering measures,due to the oversized scales.The hazard mitigation measures such as monitoring and prediction are proposed. 展开更多
关键词 TIBET The Brahmaputra The Mt Namjagbarwa Zelongnong Ravine debris-flow
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Modeling Experiment of Break of Debris-Flow Dam 被引量:3
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作者 CHENG Zunlan GENG Xueyong +1 位作者 DANG Chao LIU Jingjing 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期588-594,共7页
Glaciers are extensively developed in the southwest of Tibet and the moraines are widely distributed with large depth. Large-scale debris flows are often reported which blocked rivers and formed dams. In this paper, s... Glaciers are extensively developed in the southwest of Tibet and the moraines are widely distributed with large depth. Large-scale debris flows are often reported which blocked rivers and formed dams. In this paper, seven large debris flows in four valleys are discussed, among which five dams developed. 13 sets of experiments have been conducted in laboratory to simulate the formation and failure of the dam. Finally, a model of dam failure is proposed and a formula is established to calculate the flood discharge: Q=kbnnk/TB^-/LG^0.1,where bk is the outlet width of the dam at the original water level, hk the erosive depth, T the time from overflow to final state of failure, the average width of lake; L the length of the lake, and G the total potential energy of the water in the lake. 展开更多
关键词 debris-flow dam OUTBURST EXPERIMENT
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Geomorphic effect of debris-flow sediments on the Min River,Wenchuan Earthquake region,western China 被引量:1
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作者 HU Xu-dong ZHOU Li-qin +2 位作者 LIU Wei-ming WANG Hao CUI Lei 《Journal of Mountain Science》 SCIE CSCD 2021年第9期2427-2440,共14页
Coseismic landslides and subsequent mobilization of sediment greatly aggravated the landscape evolution and river sedimentation after the Wenchuan earthquake.The debris-flow alluvial fan and river morphological index ... Coseismic landslides and subsequent mobilization of sediment greatly aggravated the landscape evolution and river sedimentation after the Wenchuan earthquake.The debris-flow alluvial fan and river morphological index was combined to describe quantitatively the effects of debris-flow sediment on the river characteristics in Longmen Mountains.The section of the Min River from the urban area of the Wenchuan county to the epicenter,the Yingxiu town in this county,was selected as the study area.We identified 27 river-blocking debrisflows(5 partial-,7 semi-,7 over semi-,and 5 fullyblocking degrees)in the study area via remote sensing interpretation and field survey.Based on this,the response of river longitudinal profile and curvature to debris-flow sediment was qualitatively and quantitatively analyzed.The results show that the channel gradient has decreased due to debris-flow aggradation,while two marked peaks in the river steepness index(ksn,represents the relative steepness degree of the channel)changed from 585 m0.9 to 732 m0.9 in zone 1,from 362 m0.9 to 513 m0.9 in zone 2.Moreover,the main channel has undergone substantial lateral migration with channel width decreased and river curvature increased.The temporal and spatial variation between river morphological characteristics and debris-flow sediments in short-term provides insights into the internal dynamic role of mass wasting processes in river morphology,which could be served as useful information for natural hazards management to prevent the river from being blocked by episodically debris flows after the earthquake. 展开更多
关键词 debris-flow sediment Longitudinal profile River curvature Min River Wenchuan earthquake
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