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Experimental study on large wood filtration performance by herringbone water-sediment separation structure

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Journal of Mountain Science 2017年第2期14卷 269-281页

作者： XIE Xiang-ping WEI Fang-qiang yang hong-juan XIE Tao Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Chongqing Jiao Tong University Chongqing 400074China

A herringbone water-sediment separation structure(hereinafter referred to as "herringbone structure") has been shown to be effective in separating coarse inorganic debris; however, less is known regarding the large wood(LW) filtration effect in this structure. This paper presents preliminary research on the wood filtration effect of the herringbone structure based on physical model *** results show that the herringbone structure exhibited effective performance in large wood size segregation, with a 100% component filtration rate for LW that diameter(D) larger than ribbed beam opening width(a). The total filtration rate also exceeded 80% when the Fraud number(Fr) is larger than 2.64 and increased with the increase of Fr. After exceeding Frmax, total filtration rate would be decreased due to overflow. Beside flow condition,structure parameters influence significantly on LW filtration rate. We attempt to explain the filtration process via particle contact trajectory and particle movement trajectory. The inclined angle of ribbed beam(γ) contributed the most variation to the filtration rate via influencing the coincidence with particle contact trajectory and particle movement trajectory. The high sensitivity coefficient of ribbed beam(θ) under relatively low Fr conditions implies remarkable influences on LW filtration effects by causing clogging problem. The ribbed beam opening width(a) together with LW diameter(D) influenced the size segregation performance.

关键词： Debris flow Large wood Herringbone water-sediment separation structure Filtration effect

A Regional-Scale Method of Forecasting Debris Flow Events Based on Water-Soil Coupling Mechanism

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Journal of Mountain Science 2014年第6期11卷 1531-1542页

作者： ZHANG Shao-jie WEI Fang-qiang LIU Dun-long yang hong-juan JIANG Yu-hong Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

A debris flow forecast model based on a water-soil coupling mechanism that takes the debrisflow watershed as a basic forecast unit was established here for the prediction of disasters at the watershed *** was achieved through advances in our understanding of the formation mechanism of debris *** expand the applicable spatial scale of this forecasting model,a method of identifying potential debris flow watersheds was used to locate areas vulnerable to debris flow within a forecast *** these watersheds as forecasting units and a prediction method based on the water-soil coupling mechanism,a new forecasting method of debris flow at the regional scale was *** order to test the prediction ability of this new forecasting method,the Sichuan province,China was selected as a study zone and the large-scale debris flow disasters attributable to heavy rainfall in this region on July 9,2013 were taken as the study *** to debris flow disaster data on July 9,2013 which were provided by the geo-environmental monitoring station of Sichuan province,there were 252 watersheds in which debris flow events actually *** current model predicted that 265 watersheds were likely to experience a debris flow *** these,43 towns including 204 debrisflow watersheds were successfully forecasted and 24 towns including 48 watersheds *** false prediction rate and failure prediction rate of thisforecast model were 23% and 19%,*** results show that this method is more accurate and more applicable than traditional methods.

关键词： Debris flow Forecasting Water-soil coupling mechanism Watershed

Determination of optimal grid opening width for herringbone water-sediment separation structures based on sediment separation efficiency

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Journal of Mountain Science 2019年第3期16卷 619-629页

作者： XIE Xiang-ping WEI Fang-qiang WANG Xiao-jun yang hong-juan Anyang Institute of Technology Chongqing Institutes of Green and Intelligent Technology Chinese Academy of Science Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The herringbone water-sediment separation structure(HWSSS) was developed to prevent debris flows. This paper mainly focuses on evaluating the sediment separation efficiency of HWSSS in debris flow prevention and determining the grid opening width D, a crucial structure parameter for HWSSS design. Theoretical analysis on the total sediment separation rate Pt reveals that the efficiency of sediment separation is much related with sediment grain size distribution(GSD) and grid opening width. The lower limit of Pt is deduced from the perspective of safety consideration by transforming debris flow into sediment-laden flow. Hydraulic model tests were carried out. Based on the regression analysis of the experimental data, the quantitative relationships between Pt and D and GSD characteristic values were finally established. A procedure for determining optimal grid opening width is proposed based on these analyses. These results are of significance in evaluating sediment separation effect by HWSSS in debris flow prevention and contribute to a more explicit methodology for design of HWSSS.

关键词： Debris flow Water-sediment separation Structure design Sediment separation efficiency Grid opening width

Field observation of debris-flow activities in the initiation area of the Jiangjia Gully, Yunnan Province, China

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Journal of Mountain Science 2022年第6期19卷 1602-1617页

作者： yang hong-juan ZHANG Shao-jie HU Kai-heng WEI Fang-qiang WANG Kai LIU Shuang Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

The Jiangjia Gully, which is located in Dongchuan District, Yunnan Province, China, is a watershed prone to debris flows and has long-term recorded data of debris-flow occurrence. However, the initiation mechanism has mainly been studied by experiments in this watershed. To further reveal debris-flow formation mechanism in the Jiangjia Gully, debris-flow activities in the initiation zone were observed with hand-held video cameras in the summer of 2016 and 2017. In these two years, six debris-flow events were triggered in Menqian Gully, a major tributary of the Jiangjia Gully, while debrisflow activities in some sub-watersheds of Menqian Gully were recorded with video cameras in four events. The video recording shows that landslides constituted an important source for sediment supply in debris flow. Some landslides directly evolved into debris flows, while the others released sediment into rills and channels, where debris flows were generated for sediment entrainment by water flow. Therefore, debris-flow occurrence in the Jiangjia Gully is influenced both by infiltration-dominated processes and by runoff-dominated processes. In addition, rainfall data from four gauges installed in Menqian Gully were analyzed using mean intensity(I), duration(D), peak 10-minute rainfall(R10min) and antecedent rainfall(AR) up to 15 days prior to peak 10-minute rainfall. It reveals that debris-flow triggering events can be discriminated from nontriggering events either by an I-D threshold or by an R10min-AR threshold. However, false alarms can be greatly reduced if these two kinds of thresholds are used together. Moreover, behaviors including intermittency of debris flow, variance in moisture content and volume among surges, and coalescence of multiple surges by temporary damming were observed, indicating the complexity of debris-flow initiation processes. These findings are expected to enhance our knowledge on debris-flow formation mechanism in regions with similar environmental settin

关键词： Debris flow Field observation Initiation mechanism Rainfall threshold Jiangjia gully

Analytical Solutions to the Time-Independent Gross-Pitaevskii Equation with a Harmonic Trap

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Chinese Physics Letters 2012年第11期29卷 8-12页

作者： SHI Yu-Ren WANG Guang-Hui LIU Cong-Bo ZHOU Zhi-Gang yang hong-juan College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070

We try to find the analytical solutions to the time-independent Gross-Pitaevskii equation,a nonlinear Schrodinger equation used in the simulation of Bose–Einstein condensates trapped in a harmonic *** the homotopy analysis method and the Galerkin spectral method are *** investigate the one-dimensional case and obtain the approximate analytical solutions *** between the analytical solutions and the numerical solutions has been *** results indicate that they agree very well with each other when the atomic interaction is not too strong.

关键词： potential equation analytical

Sequence-activated chemiluminescence probes:programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang juan Li Wei-hong Zhu Zhiqian Guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular EngineeringInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science&TechnologyShanghai 200237China

Sequence-activated chemiluminescence(CL)technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial *** fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest,thus enabling high-contrast signals under complex physiological *** sequential activation could be triggered by enzymes,reactive oxygen species(ROS),biothiols or changes in the *** unique sequence-activated CL probes bestow several advantages,including minimal background,deep-tissue penetration,and the ability of non-invasive or minimally invasive *** sequence-activated CL techniques represent a significant advancement in molecular imaging and *** this mini-review,we focus on the latest developments in sequential CL probes,addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

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股动脉穿刺置管术后快速手法压迫止血的体会

介入放射学杂志 2013年第5期22卷 412-414页

作者：杨卷红宝鸡市中心医院介入科陕西721008

目的探讨股动脉穿刺置管术后快速手法压迫止血的止血效果及并发症。方法总结了一套快速手法压迫止血的方法(平均止血时间约2 min),并对324例行介入股动脉穿刺置管患者术后立即进行快速手法压迫止血,术后1 d对患者穿刺点周围的皮肤观察... 详细信息

目的探讨股动脉穿刺置管术后快速手法压迫止血的止血效果及并发症。方法总结了一套快速手法压迫止血的方法(平均止血时间约2 min),并对324例行介入股动脉穿刺置管患者术后立即进行快速手法压迫止血,术后1 d对患者穿刺点周围的皮肤观察并行相应的触诊检查。结果 324例经股动脉穿刺置管介入术后患者均用了快速手法压迫止血,其中4例患者穿刺点周围皮下片状淤青,余患者穿刺点周围未见明显淤青,其有效止血率高达98.8%(320/324)。320例患者中6例患者穿刺点周围出现局部皮肤轻度压伤,未予处理1周后均自行修复。结论股动脉穿刺置管介入诊疗术后快速手法压迫止血是一种省时、省力、安全、经济、可重复、环保、实用的止血方法。

关键词：股动脉穿刺置管快速手法压迫止血

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同伦分析法在求解耗散系统中的应用

物理学报 2010年第1期59卷 67-74页

作者：石玉仁杨红娟西北师范大学物理与电子工程学院兰州730070

利用同伦分析法求解了KdV-Burgers方程,得到了它的解析近似解,该解与精确解符合得非常好.结果表明同伦分析法在求解某些耗散系统时,仍然是一种行之有效的方法.

关键词：同伦分析法 KdV—Burgers方程解析解

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中国火电企业生产效率评价与影响因素研究

中国环境科学 2019年第11期39卷 4910-4920页

作者：张吉岗杨红娟昆明理工大学管理与经济学院云南昆明650093 昆明理工大学城市学院云南昆明650051

基于2008~2017年省级统计数据,研究中国火电企业生产效率与影响因素.首先,运用Bootstrap方法修正的DEA模型研究火电企业静态效率;其次,结合全局参比Malmquist指数的可传递性研究火电企业动态效率;最后,运用Tobit模型研究火电企业生产效... 详细信息

基于2008~2017年省级统计数据,研究中国火电企业生产效率与影响因素.首先,运用Bootstrap方法修正的DEA模型研究火电企业静态效率;其次,结合全局参比Malmquist指数的可传递性研究火电企业动态效率;最后,运用Tobit模型研究火电企业生产效率影响因素,基于稳健性考虑运用固定效应模型验证检验结果的可靠性.效率评价实证结果显示:2008~2017年无一省(自治区、直辖市)的火电企业生产效率处于生产前沿面,也无一省(自治区、直辖市)的火电企业生产效率持续提高.2008~2013年全国火电企业生产效率比较平稳,2013~2016年呈下降趋势且省际差异逐步扩大,2017年有所回升.2008~2017年东中西三大地带火电企业效率和平稳性呈现东部最优、中部次之、西部最差的格局.影响因素实证结果显示:设备性能、经济发展速度、市场竞争程度是火电企业生产效率的显著影响因素;政府对环境污染重视程度和碳排放权交易市场对火电企业生产效率影响有限.

关键词：火电企业 Bootstrap方法 DEA-Tobit模型生产效率影响因素