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Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation

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Journal of Mountain Science 2016年第2期13卷 234-245页

作者： FAN Xiao-yi tian shu-jun ZHANG You-yi State Key Laboratory of Geo-Hazard Prevention and Geo-Environment Protection Chengdu University of Technology School of Civil Engineering and Architecture Southwest University of Science and Technology

The mass-front velocities of granular flows results from the joint action of particle size gradations and the underlying ***,because of the complexity of friction during flow movement,details such as the slope-toe impedance effects and momentum-transfer mechanisms have not been completely explained by theoretical analyses,numerical simulations,or field *** study the mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradations we conducted model experiments that recorded the motion of rapid and long-runout rockslides or *** tests were conducted using slope angles of 25°,35°,45°,and 55° and three particle size *** resulting mass-front motions consisted of three stages:acceleration,velocity maintenance,and *** existing methods of velocity prediction could not explain the slowing effect of the slope toe or the momentum-transfer steady velocity *** the slope angle increased from 25° to 55°,the mass-front velocities dropped significantly to between 44.4% and59.6% of the peak velocities and energy lossesincreased from 69.1% to 83.7% of the initial,*** velocity maintenance stages occurred after the slope-toe and mass-front velocity *** this stage,travel distances increased as the angles increased,but the average velocity was greatest at 45°.At a slope angle of 45°,as the median particle size increased,energy loss around the slope toe decreased,the efficiency of momentum transfer increased,and the distance of the velocity maintenance stage *** presented an improved average velocity formula for granular flow and a geometrical model of the energy along the flow line.

关键词： Granular flow Angle of slope Runout plane Particle size gradation Mass-front velocity Energy-profile

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Phosphate-Solubilizing and -Mineralizing Abilities of Bacteria Isolated from Soils

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Pedosphere 2008年第4期18卷 515-523页

作者： TAO Guang-Can tian shu-jun CAI Miao-Ying XIE Guang-Hui Laboratory of Energy Crops College of Agronomy and Biotechnology China Agricultural University Beijing 100094 （China）. Institute of Microbiology Chinese Academy of Sciences Beijing 100080 （China）

Microorganisms capable of solubilizing and mineralizing phosphorus （P） pools in soils are considered vital in promoting P bioavallability. The study was conducted to screen and isolate inorganic P-solubilizing bacteria （IPSB） and organic P-mineralizing bacteria （OPMB） in soils taken from subtropical flooded and temperate non-flooded soils, and to compare inorganic P-solubilizing and organic P-solubilizing abilities between IPSB and OPMB. Ten OPMB strains were isolated and identified as Bacillus cereus and Bacillus megaterium, and five IPSB strains as B. megaterium, Burkholderia caryophyUi, Pseudomonas cichorii, and Pseudomonas syringae. P-solubilizing and -mineralizing abilities of the strains were measured using the methods taking cellular P into account. The IPSB strains exhibited inorganic P-solubilizing abilities ranging between 25.4-41.7 μg P mL^-1 and organic P-mineralizing abilities between 8.2-17.8μg P mL^-1. Each of the OPMB strains also exhibited both solubilizing and mineralizing abilities varying from 4.4 to 26.5 μg P mL^-1 and from 13.8 to 62.8 μg P mL^-1, respectively. For both IPSB and OPMB strains, most of the P mineralized from the organic P source was incorporated into the bacterial cells as cellular P. A significantly negative linear correlation （P 〈 0.05） was found between culture pH and P solubilized from inorganic P by OPMB strains. The results suggested that P solubilization and mineralization could coexist in the same bacterial strain.

关键词： Bacillus sp. Burkholderia sp. inorganic phosphate-solubilizing bacteria organic phosphorus-mineralizing bacteria Pseudomonas sp.

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Numerical simulation of a high-speed landslidein Chenjiaba, Beichuan, China

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Journal of Mountain Science 2017年第11期14卷 2137-2149页

作者： HUANG Tao DING Ming-tao SHE Tao tian shu-jun YANG Jiang-tao School of Environment and Resources Southwest University of Science and Technology Faculty of Geosciences and Environmental Engineering Southwest Jiaotong University Institute of Exploration Technology Chinese Academy of Geological Sciences School of Civil Engineering and Architecture Southwest University of Science and Technology

High-speed landslide is a catastrophic geological disaster in the mountainous area of southwest China. To predict the movement process of landslide reactivation in Chenjiaba town, Beichuan county, Sichuan province, China, we simulated the movement process of two landslide failures in Chenjiaba via rapid mass movement simulation and unmanned aerial vehicle images(UAV), and obtained the movement characteristic parameters of the landslides. According to a back analysis, the most remarkable fitting rheological parameters were friction coefficient(μ=0.18) and turbulence(). The parameter of landslide pressure was applied as the zoning index of landslide hazard to obtain the influence zone and hazard zoning map of the Chenjiaba landslide. Results show that the Duba River was blocked quickly with a landslide accumulation at the maximum height of 44.14 mwhen the Chenjiaba deposits lost stability. The hazard zoning map indicated that the landslide hazard degree is positively correlated with the *** landslide assessment is a quantitative hazard assessment method based on a landslide movement process and is suitable for high-speed landslide. Such method can provide a scientific basis for urban construction and planning in the landslide hazard area to avoid hazards effectively.

关键词： Mass movement simulation High speedlandslide Numerical simulation Hazard assessment Chenjiaba landslide Landslide pressure

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The composition of magmatic-hydrothermal fluids and their related metal mineralization

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Science China Earth Sciences 2025年第1期68卷 208-225页

作者： Qihai shu jun DENG State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and Resources China University of Geosciences Frontiers Science Center for Deep-time Digital Earth China University of Geosciences

Magmatic hydrothermal deposits are important sources of many bulk, precious, and rare metals, and have attracted interest from both academic and industrial communities. However, it is still unclear if the major enrichment of the ore-forming metals occurs in the parental magma source region, during the magma evolution, or after the fluid exsolution. Fluid inclusions trapped in hydrothermal minerals crystallized in the early, high-temperature stage before metal precipitation record information close to that of the initially exsolved magmatic fluids, which are helpful in revealing whether the metals have been already significantly enriched prior to the hydrothermal stage. In this study, available compositional data of such early-stage fluid inclusions from magmatic hydrothermal systems globally have been compiled. The results indicate that the concentrations of Cu,Sn, and W respectively from the Cu-, Sn-, and W-mineralized fluids are significantly higher than the hydrothermal systems that do not produce ores with the corresponding metals. This suggests that Cu, Sn, and W could have already been enriched in the magma source and/or magma evolution stage. The Mo concentrations show no difference between Mo-mineralized and Mobarren fluid systems, indicating no significant pre-enrichment in the source region or during the magma evolution. This also implies that an efficient collection of Mo from a large volume of magmas is required to account for the formation of a large Mo deposit. Almost all the hydrothermal fluids contain high concentrations of Fe and Zn-Pb, but only a few of them eventually form Fe or Zn-Pb deposits, reflecting an important role of the hydrothermal evolution process on the selective metal *** above results indicate that different metals are enriched in different stages of a magmatic hydrothermal system, and that the major roles played in the formation of a deposit vary with the metal types. In addition to the metal concentrations in the o

关键词： Magmatic hydrothermal deposits Fluid inclusions LA-ICP-MS Metal enrichment Mineralization mechanism

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液压管路动态特性的Simulink仿真研究

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系统仿真学报 2006年第5期18卷 1136-1138,1146页

作者：田树军张宏大连理工大学机械工程学院辽宁大连116023

研究液压管路的动态特性及其仿真实现方法对液压系统优化设计及其性能分析具有重要的意义。根据包含有动态摩擦项液压管路分段集中参数建模的思想,以功率键合图推导出的输入势输出势模型为基础,提出应用Matlab软件中的动态仿真工具Simul... 详细信息

研究液压管路的动态特性及其仿真实现方法对液压系统优化设计及其性能分析具有重要的意义。根据包含有动态摩擦项液压管路分段集中参数建模的思想,以功率键合图推导出的输入势输出势模型为基础,提出应用Matlab软件中的动态仿真工具Simulink软件包对液压管路的动态特性进行仿真的分析方法,液压冲击实例表明该仿真方法应用于管路的动态分析实用方便;创建的管路模型及得出的仿真结果可为液压集成块和其他液压管网动态特性的研究提供借鉴。

关键词： Simulink 液压管路功率键合图动态特性

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专题报告-S5环境污染与人体健康

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中国药理学与毒理学杂志 2006年第3期20卷 174-177页

作者： CAO Jia tian Huan-jun shu Wei-Qun Preventive Medicine College the Third Military Medical University Chongqing 400038 China

Many organic pollutants occur in drinking water in considerable amounts, and mimic or interfere with reproductive development and function. Furthermore, it is not known whether multiple organic pollutants （MOP） from... 详细信息

关键词： Environment Pollution Human Health multiple organic pollutants

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Extensive application of rate transient method in performance analysis for low permeability gas reservoirs

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Journal of Energy and Power Engineering 2009年第3期2卷 29-33页

作者： WANG Shao-jun HE shun-li tian shu-bao ZHANG jun-jing Faculty of Oil and Gas Engineering China University of Petroleum Beijing 102200 China

Rate transient method is a recently-developed performance analysis tool specially designed for low-permeability or tight gas reservoirs. This method, theoretically based on pressure transient analysis, integrates material balance principle and the concept of material balance pseudo-time proposed by Blansingame. With daily production data of gas well, it could be used to calculate OGIP, current formation pressure, permeability, skin factor, to identify complex geologic boundaries, to determine whether drainage boundary has been reached, to calculate drainage area and drainage radius for single well and to predict performance. It has been extensively employed in more than ten low-permeability gas fields. It proves that most problems in performance analysis for low permeability gas reservoirs could be solved by this method. Field practices show great economical benefits could be achieved by employing this method in gas field development.

关键词： low permeability gas reservoir performance analysis rate transient method

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地震碎裂滑动型滑坡发育特点及典型实例分析

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四川大学学报（工程科学版） 2009年第3期41卷 119-124页

作者：孔纪名崔云田述军阿发友中国科学院山地灾害与地表过程重点实验室四川成都610041 中国科学院水利部成都山地灾害与环境研究所四川成都610041 中国科学院研究生院北京100039

汶川地震诱发了大量的地震滑坡,其中地震碎裂滑动型滑坡是一种普遍的地震滑坡类型,滑动特征独特,动力机制复杂。以汶川县映秀镇牛圈沟滑坡为典型实例,从发育碎裂滑动的地貌、岩性、斜坡结构、地震作用等关键控制因素出发,阐释了牛圈沟... 详细信息

汶川地震诱发了大量的地震滑坡,其中地震碎裂滑动型滑坡是一种普遍的地震滑坡类型,滑动特征独特,动力机制复杂。以汶川县映秀镇牛圈沟滑坡为典型实例,从发育碎裂滑动的地貌、岩性、斜坡结构、地震作用等关键控制因素出发,阐释了牛圈沟滑坡的"滑动启动-碰撞碎裂-碎屑滑动-堆积停滞"4个阶段碎裂滑动中的7次折向过程,应用"地震启动-碎裂-加速"机理能够很好的解释地震滑坡超高速、滑程远、规模大的特点,具有一定的典型性和学科意义。

关键词： “5·12”汶川大地震碎裂滑动型滑坡牛圈沟滑坡实例

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汶川地震山地灾害对环境因素的响应机制

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四川大学学报（工程科学版） 2010年第5期42卷 92-98页

作者：田述军孔纪名阿发友崔云中国科学院水利部成都山地灾害与环境研究所四川成都610041 中国科学院研究生院北京100039

为了研究汶川地震山地灾害灾害分布对环境因素的响应机制,通过对汶川地震灾区的调查和遥感解译,详细分析灾害分布特点,用GIS平台对4722个典型灾害点的环境因素进行分析,得出以下结论:1)地震能量释放的长短轴效应造成地震能量主要沿断裂... 详细信息

为了研究汶川地震山地灾害灾害分布对环境因素的响应机制,通过对汶川地震灾区的调查和遥感解译,详细分析灾害分布特点,用GIS平台对4722个典型灾害点的环境因素进行分析,得出以下结论:1)地震能量释放的长短轴效应造成地震能量主要沿断裂带释放,灾害点沿中央断裂呈条带状分布,在距中央断裂20km范围内集中灾害总数的64.42%,逆冲断裂的上下盘效应使上盘灾害发育程度明显高于下盘和下盘灾害密度经历先降低后升高再降低的变化;2)灾害点在山地地区集中分布在河谷两岸,河谷岸坡对地震的放大作用使坡体上部岩土首先崩解,带动坡体下部的岩土一起运动,形成"山剥皮"特点的崩滑型灾害;3)灾害总数的99.43%集中分布在地震烈度Ⅶ度及其以上地区,地震的场地效应使灾害在易滑岩层中较为发育;4)在区域地势变化与地震断裂破裂一致的方向上有利于地震能量的传播,灾害更容易发生,规模较大的滑坡主滑方向也大多数发生在两者的并集方向。

关键词：山地灾害环境因素场地效应汶川大地震

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液压集成块内部孔道流场的CFD仿真分析

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系统仿真学报 2007年第17期19卷 4061-4064页

作者：王永安张宏田树军大连理工大学精密与特种加工教育部重点实验室大连116024

针对液压集成块内部孔道中液流的复杂性流动,应用计算流体动力学(CFD)方法对孔道中的流场进行数值模拟。根据孔道的物理模型建立起相应的数值模型,并对数值模型进行求解;模拟结果表明工艺孔冗余容腔对孔道压降产生影响;分析了流场特征... 详细信息

针对液压集成块内部孔道中液流的复杂性流动,应用计算流体动力学(CFD)方法对孔道中的流场进行数值模拟。根据孔道的物理模型建立起相应的数值模型,并对数值模型进行求解;模拟结果表明工艺孔冗余容腔对孔道压降产生影响;分析了流场特征与孔道结构的关系,探讨了造成液流压力损失的原因,为孔道结构的改进提供依据。

关键词：液压集成块孔道计算流体动力学流场

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