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Characteristics,Causes and Mitigation of Catastrophic Debris Flow Hazard on 21 July 2011 at the Longda Watershed of Songpan County,China

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Journal of Mountain Science 2013年第2期10卷 261-272页

作者： GE yong-gang CUI Peng GUO Xiao-jun SONG Guo-hu LIU Wei-ming Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences

Debris flow is a common natural hazard in the mountain areas of Western China due to favorable natural conditions, and also exacerbated by mountainous exploitation activities. This paper concentrated on the characteristics, causes and mitigation of a catastrophic mine debris flow hazard at Longda Watershed in Songpan County, Sichuan Province, on 21 July 2011. This debris flow deposited in the front of the No.1 dam, silted the drainage channel for flood and then rushed into tailing sediment reservoir in the main channel and made the No.2 dam breached. The outburst debris flow blocked Fu River, formed dammed lake and generated outburst flood, which delivered heavy metals into the lower reaches of Fu River, polluted the drink water source of the population of over 1 million. The debris flow was characterized with a density of 1.87～2.15 t/m3 and a clay content of less than 1.63%. The peak velocity and flux at Longda Gully was over l0.0～10.9 m/s and 429.o～446.o m3/s, respectively, and the flux was about 700 m3/s in main channel, equaling to the flux of the probability of 1%. About 33o,ooorn3 solid materials was transported by debris flow and deposited in the drainage tunnel （120,000～130,000 m3）, the front of No.1 dam （100,000 m3） and the mouth of the watershed （l00,000～110,000 m3）, respectively. When the peak flux and magnitude of debris flow was more than 462 m3/s and 7,423 m3, respectively, it would block Fu River and produce a hazard chain which was composed of debris flow, dammed lake and outburst flood. Furthermore, the 21 July large-scale debris flow was triggered by rainstorm with an intensity of 21.2 mm/0.5 h and the solid materials of debris flow were provided by landslides, slope deposits, mining wastes and tailing sediments. The property losses were mainly originated from the silting of the drainage tunnel for flash flood but not for debris flow and the irrational location of tailing sediment reservoir. Therefore, the mitigation measures for mine debris flows

关键词： Debris Flow Characteristics Causes Mitigation Longda Watershed

Investigation of a real-time location system of corneal astigmatic axis

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Eye and Vision 2017年第1期4卷 121-126页

作者： Jian-Guo Zhao An-Peng Pan Ke Zheng A-yong yu The Eye Hospital of Wenzhou Medical University 270 Xueyuan West RoadWenzhou(325000)ZhejiangPeople’s Republic of China

Background:To construct a real-time computerized location system(RCLS)to analyze and display the axis of corneal astigmatism and to compare its accuracy with the Scheimpflug ***:Fifty-seven eyes of 39 volunteers with corneal astigmatism more than 1.00 diopter(D)were *** RCLS was composed of a circular light-emitting diode(LED)light source,surgical microscope,surgical video system,computer and self-programming image analysis *** imaging measurements(Pentacam HR,Oculus,Wetzlar,Germany)were performed on all subjects to determine the axis and power of corneal ***,the axis of corneal astigmatism was analyzed in real-time and displayed by the RCLS on supine position,and videos were *** MB-Ruler 4.0 software was used to measure the astigmatic *** accuracy of the RCLS was compared with the Scheimpflug ***:The RCLS was able to display the axis of corneal astigmatism in *** axial deviation of corneal astigmatism between the two methods was 0.63±3.78°when astigmatism was 1.00 to 2.00 D and decreased to 0.06±1.38°when astigmatism was greater than 2.00 D.A linear correlation of astigmatic axis was noted between the two methods:Axis_(RCLS)=1.01×Axis_(Scheimpflug)−1.02(R^(2)=0.998,P<0.001).The Bland-Altman analysis revealed that the RCLS agreed sufficiently well with the Scheimpflug ***:The RCLS can accurately analyze and display the axis for corneal astigmatism greater than 1.00 D in *** RCLS simplifies marking procedures and may have potential clinical application to improve the postoperative visual outcomes in surgical correction of corneal astigmatism.

关键词： Corneal astigmatism Location Real time Mark

An Isentropic Mass Circulation View on the Extreme Cold Events in the 2020/21 Winter

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Advances in Atmospheric Sciences 2022年第4期39卷 643-657页

作者： yueyue yu Yafei LI Rongcai REN ming CAI Zhaoyong GUAN Wei HUANG Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Institute for Climate and Application Research(ICAR)Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Tianjin Meteorological Disaster Defense Technology Centre Tianjin 300074China Department of Earth Ocean&Atmospheric SciencesFlorida State UniversityTallahasseeFlorida 32304USA Key Laboratory of Mesoscale Severe Weather/Ministry of Education and School of Atmospheric Sciences Nanjing UniversityNanjing 210044China

Three extreme cold events successively occurred across East Asia and North America in the 2020/21 *** study investigates the underlying mechanisms of these record-breaking persistent cold events from the isentropic mass circulation(IMC)*** show that the midlatitude cold surface temperature anomalies always co-occurred with the high-latitude warm anomalies,and this was closely related to the strengthening of the low-level equatorward cold air branch of the IMC,particularly along the climatological cold air routes over East Asia and North ***,the two cold surges over East Asia in early winter were results of intensification of cold air transport there,influenced by the Arctic sea ice loss in *** weakened cold air transport over North America associated with warmer northeastern Pacific sea surface temperatures(SSTs)explained the concurrent anomalous warmth *** enhanced a wavenumber-1 pattern and upward wave propagation,inducing a simultaneous and long-lasting stronger poleward warm air branch(WB)of the IMC in the stratosphere and hence a displacement-type Stratospheric Sudden Warming(SSW)event on 4 *** WB-induced increase in the air mass transported into the polar stratosphere was followed by intensification of the equatorward cold branch,hence promoting the occurrence of two extreme cold events respectively over East Asia in the beginning of January and over North America in *** do not yield a robust direct linkage from La Niña to the SSW event,IMC changes,and cold events,though the extratropical warm SSTs are found to contribute to the February cold surge in North America.

关键词： isentropic mass circulation extreme cold event Stratospheric Sudden Warming La Niña Arctic sea ice extratropical sea surface temperature

Corrosion and Cavitation Erosion Behaviours of Cast Nickel Aluminium Bronze in 3.5% NaCl Solution with Different Sulphide Concentrations

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1470-1482页

作者： Qi-Ning Song Nan Xu Yao Tong Chen-ming Huang Shou-yu Sun Chen-Bo Xu Ye-Feng Bao yong-Feng Jiang Yan-Xin Qiao Zhi-yuan Zhu Zheng-Bin Wang College of Mechanical and Electrical Engineering Hohai University200 Jinling North RoadChangzhou 213022China College of Materials Science and Engineering Jiangsu University of Science and Technology2 Mengxi RoadZhenjiang 212003China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences62 Wencui RoadShenyang 110016China

The effect of sulphide(Na2S)concentration(SC)on the corrosion and cavitation erosion behaviours of a cast nickel aluminium bronze(NAB)in 3.5% NaCl solution is investigated in this *** results show that when the SC exceeds 50 ppm,the hydrogen evolution reaction dominates the cathodic process,and a limiting current region appears in the anodic branch of the polarisation curve due to the formation of a copper sulphide film,which is a diffusion-controlled *** longterm immersion,the increased mass loss rate of NAB with the sulphide additions of 20 and 50 ppm is attributed to the less protective films,which contains a mixture of copper oxides and ***,NAB undergoes severe localised corrosion(selective phase corrosion,SPC)at the β’phases and eutectoid microstructureα+κⅢ.By comparison,NAB undergoes general corrosion and a copper sulphide film is formed in 100 and 200 ppm sulphide *** erosion greatly increases the corrosion rate of NAB in all solutions and causes a negative potential shift in 3.5%NaCl solution due to the film ***,a positive potential shift occurs in the solutions with SC higher than 50 ppm due to the accelerated mass transfer of the cathodic *** cavitation erosion mass loss rate of NAB increases with the increase of *** occurrence of severe SPC decreases the phase boundary cohesion and causes brittle fracture under the cavitation *** corrosion-enhanced erosion is the most predominant factor for the cavitation erosion damage when the SC exceeds 50 ppm.

关键词： Nickel aluminium bronze Sulphide Corrosion Cavitation erosion Synergy

The morphology, kinematics and metallicity of blue-core galaxies

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Research in Astronomy and Astrophysics 2019年第6期19卷 51-62页

作者： yong-yun Chen Yan-Mei Chen Qiu-Sheng Gu yong Shi Long-Ji Bing Xiao-Ling yu School of Astronomy and Space Science Nanjing University Nanjing 210093 China Collaborative Innovation Center of Modern Astronomy and Space Exploration Nanjing 210093 China

We select 107 blue-core galaxies from the MaNGA survey, studying their morphology, kinematics as well as the gas-phase metallicity. Our results are as follows:(i) In our sample, 26% of blue-core galaxies have decoupled gas-star kinematics, indicating external gas accretion;15% have bar-like structure and 8% show post-merger features, such as tidal tails and irregular gas/star velocity field. All these processes/features, such as accreting external misaligned gas, interaction and bar, can trigger gas inflow. Thus the central star-forming activities lead to bluer colors in their centers(blue-core galaxies).(ii) By comparing with the SDSS DR7 star-forming galaxy sample, we find that the blue-core galaxies have higher central gas-phase metallicity than what is predicted by the local mass-metallicity relation. We explore the origin of the higher metallicity, finding that not only the blue-core galaxies, but also the flat-gradient and red-core galaxies all have higher metallicity. This can be explained by the combined effect of redshift and galaxy color.

关键词： galaxies abundances-galaxies formation-galaxies structure

Flux of organic carbon burial and carbon emission from a large reservoir: implications for the cleanliness assessment of hydropower

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Science Bulletin 2019年第9期64卷 603-611页

作者： Fushun Wang yunchao Lang Cong-Qiang Liu yong Qin Ningxiao yu Baoli Wang School of Environmental and Chemical Engineering Shanghai University Institute of Surface-Earth System Sciences Tianjin University

Accurately quantifying the budget of carbon sources and sinks in hydropower reservoirs is important for evaluating the cleanliness of hydroelectricity. However, current research on carbon emissions from reservoirs has rarely taken into account the organic carbon(OC) buried in sediment. Only greenhouse gas emissions from the water-air interface at reservoirs have been examined, which would result in an overestimation of the greenhouse effect of reservoirs. In November 2017, this study investigated the distribution of sediment in the Hongfeng Reservoir(HFR) in southwest China, a typical large hydropower reservoir, by using an underwater seismology monitoring system. We estimated the flux of OC into sediment using the results of a sediment survey and a dataset compiled from references. Our results show that, the HFR retained 200,715 t of OC in the sediment since its impounding after dam construction to the sampling year of 2017, when the average burial flux was 3,521 t-C aà1(106 g C aà1) and the modern burial flux was 5,449 t-C aà1. After excluding the exogenous OC, the modern valid carbon sink of the sediment was 4,632 t per year. Under the current state of the reservoir, taking the modern valid carbon sink value, the carbon emissions from the reservoir's surface, and the discharge water from the dam into consideration, the net carbon sink of the HFR is found to be 1,098.9 t-C aà1. If the hydroelectricity generated by the reservoir is converted to a carbon sink, then the total net carbon sink becomes 12,972.9 t-C aà*** work argues that both reservoir sediment and hydroelectricity are important carbon sinks and both should be included in assessments of the greenhouse effects of reservoirs.

关键词： The Hongfeng Reservoir Sediment Carbon sink Underwater seismology method

Improvement of wood properties by composite of diatomite and “phenol-melamine-formaldehyde” co-condensed resin

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Journal of Forestry Research 2013年第4期24卷 741-746页

作者： ZHANG ming XU Yang WANG Shu-liang SHI Jun-you LIU Chang-yu WANG Cheng-yu College of Materials Science and Engineering Northeast Forestry University China Nation Center for Quality Supervision and Test of Wood working Machinery Northeast Forestry University Wood Material Science and Engineering Key Laboratory of Jilin Province Beihua University

We improved the overall performance of fast-growing poplar by utilizing a low-cost, effective and simple method. The fast-growing poplar was modified by a vacuum-pressure impregnation method with three types of modification solutions composed of phe- nol-melamine-formaldehyde （PMF） co-condensed resin, diatomite, and 3-aminopropyl （diethoxy） methylsilane. We measured the weight percent gain （WPG）, bulking, leaching, anti-swelling efficiency （ASE）, wa- ter-repellent effectiveness （WRE）, and oxygen index of the modified specimens. All of the wood physical properties, which are beneficial for human uses, were significantly improved by the treatment. We improved various characteristics of wood and the oxygen index of poplar above 48.6% after the modification using diatomite and PMF co-condensed resin.

关键词： Keywords: wood modification phenol-melamine-formaldehydeco-condensed resin artificial fast-growing poplar diatomite

肿瘤生长方式影像学表现对骨肉瘤预后影响的临床研究

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骨科 2024年第4期15卷 332-338页

作者：乔相帅郑凯徐明于秀淳锦州医科大学研究生学院辽宁锦州121001 中国人民解放军联勤保障部队第九六〇医院骨病科济南250031

目的探讨骨肉瘤生长方式与病人预后的相关性。方法收集2007年1月至2018年8月于中国人民解放军联勤保障部队第九六〇医院确诊为四肢骨肉瘤的119例病人的病历资料。根据MRI图像所显示的骨肉瘤生长方式将病人分为均匀生长型、渐进生长型和... 详细信息

目的探讨骨肉瘤生长方式与病人预后的相关性。方法收集2007年1月至2018年8月于中国人民解放军联勤保障部队第九六〇医院确诊为四肢骨肉瘤的119例病人的病历资料。根据MRI图像所显示的骨肉瘤生长方式将病人分为均匀生长型、渐进生长型和纵向生长型。Fisher精确检验分析骨肉瘤生长方式与病人临床特征之间的相关性;Kaplan-Meier分析病人5年无事件生存率和5年总生存率,通过Log-rank分析其生存差异;Cox比例风险模型进行多因素分析。结果均匀生长型44例(37.0%),渐进生长型35例(29.4%),纵向生长型40例(33.6%)。三型骨肉瘤病人比较,纵向生长型初诊转移率最高(χ^(2)=14.615,P=0.001);均匀生长型肿瘤体积较小,纵向生长型肿瘤体积较大,渐进生长型肿瘤体积介于两者之间(χ^(2)=29.322,P<0.001);均匀生长型化疗效果优于渐进生长型和纵向生长型(χ^(2)=6.640,P=0.035);均匀生长型局部复发率低,渐进生长型和纵向生长型局部复发率高(χ^(2)=8.005,P=0.023);纵向生长型远处转移率高,渐进生长型次之,均匀生长型远处转移率低(χ^(2)=6.708,P=0.037);均匀生长型、渐进生长型和纵向生长型5年总生存率分别为72.7%、65.7%和50.0%(χ^(2)=17.407,P<0.001);均匀生长型、渐进生长型和纵向生长型5年无事件生存率分别为63.6%、51.4%和37.5%(χ^(2)=15.477,P<0.001)。多因素预后分析表明肿瘤生长方式、肿瘤体积、肿瘤体积比率、Enneking分期对病人生存具有明显统计学意义,系独立预后因素(P<0.05)。结论骨肉瘤生长方式可以作为判断骨肉瘤预后的重要参考依据之一,均匀生长型预后较好,渐进生长型次之,纵向生长型预后较差。

关键词：骨肉瘤四肢磁共振成像肿瘤大小预后

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高寒草甸斑块化空间分异性及其地形因子影响

草地学报 2024年第2期32卷 570-578页

作者：王祎明李国荣李希来把熠晨王克钰姚文治张静青海大学地质工程系青海西宁810016 青海大学农牧学院青海西宁810016

青藏高原高寒草甸在国家生态环境保护战略中占据重要位置,近几十年来,气候变化和人为因素导致大面积高寒草甸发生斑块化退化。为探究高寒草甸斑块化空间分异性及各斑块类型间(裸地斑块、短期恢复斑块和长期恢复斑块)的分布规律以及其地... 详细信息

青藏高原高寒草甸在国家生态环境保护战略中占据重要位置,近几十年来,气候变化和人为因素导致大面积高寒草甸发生斑块化退化。为探究高寒草甸斑块化空间分异性及各斑块类型间(裸地斑块、短期恢复斑块和长期恢复斑块)的分布规律以及其地形因子的影响,本研究通过3S(RS,GIS,GNSS)技术获取位于青海省河南县和玛多县4个典型研究区的斑块类型分布及地形因子数据,利用景观生态指数探究不同斑块的空间分布差异。结果表明,研究区植被覆盖度随着海拔升高呈现先增加后减小的趋势,斑块景观的破碎化程度呈现先减小后增大的趋势。不同海拔地区斑块化程度最高的斑块类型都是长期恢复斑块。地形因子显著影响着不同斑块的分布,长期恢复斑块和健康草甸主要分布在阳坡平缓区域。

关键词：斑块化植被覆盖度景观格局地形因子空间差异