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Analysis on the Dynamical Process of Donghekou Rockslide-Debris Flow Triggered by 5.12.Wenchuan Earthquake

Journal of Mountain Science 2011年第2期8卷 140-148页

作者： SUN Ping ZHANG Yongshuang SHI Jusong CHEN Liwei Key Laboratory of Neotectonic Movement & Geohazard Ministry of Land and Resources Beijing China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China China Nuclear Power Engineering corporation Ltd. Beijing China

Among the geo-hazards caused by the great Wenchuan Earthquake, the rapid and long runout rockslide-debris flow is of primary concern due to the large volume of displaced material and the resultant catastrophic impacts to the landscape and socioeconomic structure. In order to analyze the dynamical process of this kind of geo-hazard, the Donghekou rockslide-debris flow is given as an example in this paper. This event, which killed 780 people, initiated at an elevation of 13.0 m with a total long run-out distance of more than 2.00 m. The slide mass is mainly composed of dolomite limestone and siliceous limestone of Sinian system, together with carbon slate and phyllite of Cambrian. During the processes from slide initiation to the final cessation of slide movement, five dynamic stages took place, here identified as the initiation stage, the acceleration of movement stage, the air-blast effect stage, the impact and redirection stage and the long runout slidematerial accumulation stage. Field investigations indicate that due to the effects of the earthquake, the dynamics of the Donghekou rockslide-debris flow are apparently controlled by geologic and tectonic conditions, the local geomorphological aspects of the terrain, and the microstructural and macroscopic mechanical properties of rocks which compose the slide mass. These three main factors which dictate the Donghekou rockslide-debris flow dynamics are discussed in detail in this paper, and significant results of field investigations and tests of materials are presented. The above dynamical processes are analyzed in this paper, and some useful conclusions have been gained.

关键词： Dynamical process Donghekou Rockslide-debris flow Wenchuan earthquake

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Analysis of the Effectiveness of Thermosiphon, Awning and Insulations Board on Permafrost Roadbed

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Engineering Sciences 2006年第2期 117-127页

作者： Liu Jiankun1, Qian Zhengyu2. Liu Fengxi3.1.Civil Engineering Institute of beijing Jiaotong University, beijing, 100044 2. Department of Science, The Ministry of Railways, beijing 3. Highway Planning & Designing Institute, China Transportation {3., beijing 100010)

In this paper, the effect of the thermosiphon, insulation board and awning in cooling the permafrost roadbed base was simulated numerically. The computed results were analysed and compared, some practical conclusion w... 详细信息

关键词： permafrost thermosiphon awning temperature field

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Numerical simulation of two-phase turbulent flow in hydraulic and hydropower engineering

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Science China(Technological Sciences) 2007年第z1期50卷 79-89页

作者： DAI HuiChao1,2., WANG LingLing1, GAO JiZhang3. ZHANG XiaoDong3.& YANG ZhongHua2.1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 2.0098, China 2.China Yangtze River Three Gorges Project Development {2., Yichang 443.02. China 3.China Institute of Water Resources and Hydropower Research, beijing 100044, China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China China Yangtze River Three Gorges Project Development corporation Yichang 443002 China China Institute of Water Resources and Hydropower Research Beijing 100044 China

In connection with the specific features of high velocity aerated flow generated by hydraulic engineering structures, the mathematical model is developed for high turbulence air-water two-phase flow with the use of twin flow theoretical model in this paper. Furthermore the numerical method is proposed to treat bubbled flows. In addition, on the basis of air-water stratified twin flow model, the new calculation methods and free surface tracking technique are proposed to describe complicated movements of the free surface. Finally, the proposed model is used to calculate artificial aerated flows. The computed results coincide quite well with experimental results. This means that the proposed method can provide solid basis for practical engineering design.

关键词： high turbulence two-phase flow twin flow model aerated flow free surface

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Circadian expression of clock genes and angiotensin Ⅱ type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

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Acta Pharmacologica Sinica 2007年第4期28卷 484-492页

作者： Hui LI~2.Nmg-ling SUN~(2.4),Jin WANG~3.Ai-jun LIU~3.Ding-feng SU~(3.4)~2.epartment of Cardiology,Peking University People's Hospital,beijing 100044,China ~3.epartment of Pharmacology,Second MilitaryMedical University,Shanghai 2.043.,China Department of Cardiology Peking University People's Hospital Beijing China Department of Pharmacology Second Military Medical University Shanghai China

Aim:To investigate whether the circadian expression of central clock genes andangiotensin Ⅱ type 1 (AT1) receptors was altered in sinoaortic-denervated (SAD)***:Male Sprague-Dawley rats underwent sinoaortic denervation or asham operation at the age of 12.*** weeks after the operation,bloodpressure and heart period were measured in the conscious state in a group ofsham-operated (n=10) and SAD rats (n=9).Rest SAD and sham-operated ratswere divided into 6 groups (n=6 in each group).The suprachiasmatic nuclei (SCN)tissues were taken every 4 h throughout the day from each group for the determi-nation of the mRNA expression of clock genes (Per2.and Bmal1) and the AT1receptor by RT-PCR;the protein expression of Per2.and Bmal1 was determined byWestern ***:Blood pressure levels in the SAD rats were similar tothose of the sham-operated ***,blood pressure variabilities signifi-cantly increased in the SAD rats compared with the sham-operated *** variation of clock genes in the SCN of the sham-operated rats was char-acterized by a marked increase in the mRNA and protein expression during ***2.and Bmal1 mRNA levels were significantly lower in the SAD rats,especially during dark *** blot analysis confirmed an attenuation ofthe circadian rhythm of the 2.clock proteins in the SCN of the SAD ***1receptor mRNA expressions in the SCN were abnormally upregulated in the lightphase,changed to a 12.h cycle in the SAD ***:The circadian varia-tion of the 2.central clock genes was attenuated in the SAD *** baroreflexdysfunction also induced a disturbance in the expression of AT1 receptors in theSCN.

关键词： circadian rhythm arterial baroreflex clock genes sinoaortic denervation reninangiotensin system

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SHRIMP zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha group in Tibet

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Science China Earth Sciences 2005年第9期48卷 1377-1386页

作者： HU Daogong1, WU Zhenhan1, JIANG Wan1, SHI Yuruo2. YE Peisheng1 & LIU Qisheng1 1. Institute of Geomechanics, Chinese Academy of Geological Sciences, beijing 100081, China 2. Institute of Geology, Chinese Academy of Geological Sciences, beijing SHRIMP Centre, beijing 10003., China 1. Institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 2. Institute of Geology Chinese Academy of Geological Sciences Beijing SHRIMP Centre 100037 Beijing China

The Nyainqêntanglha group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha group, 10 km west of Nam Co in{2.ern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (SHRIMP). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha group is constrained by U-Pb age of 748±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the{2.ern margin of the India shield. The inherited zircons from the tholetiite and granite give older 2.7Pb/2.6Pb ages from 947 to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time.

关键词： Nyainqêntanglha group, SHRIMP dating, Nd isotope, Neoproterozoic, Tibet.

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Thermodynamic Analysis of Desulfurization and Its Connection With Deoxidation and Temperature for SPHC in JISC During LF Refining Process

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Journal of Iron and Steel Research International 2011年第S2期18卷 135-140页

作者： GUO Jing1, CHENG Zi-jian1,2. CHENG Shu-sen1, CHENG Ze-wei1, ZOU Ming2. MA Ming-sheng2.(1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology of beijing, beijing 10008{2. China 2. China’s Hongxing Stock Company of Jiugang,Jiugang 7{2.000,Gansu,China) Univ Sci & Technol beijing State Key Lab Adv Met Beijing 100083 Peoples R China Chinas Hongxing Stock Co Jiugang Jiugang 735000 Gansu Peoples R China

The thermodynamic characteristics of desulfurization reaction (CaO)+[S]=(CaS)+[O] is analyzed based on the detailed composition of liquid steel and slag of Steel Plate Hot Commercial (SPHC) in Jiuquan Iron & Steel corporation(JISC), where the activities of CaO, CaS and Al2.3.in molten slag are calculated by thermodynamic software FactSage for a more accurate result. The critical values of [O%]/[S%] for desulfurization at different temperature is are obtained, typically 0.09 at 1873., which shows directly that it should deoxidize adequately for obtaining a favorable desulfurization condition. In addition, the thermodynamic analysis indicates that the actual dissolved O is much higher than that of equilibrium calculation which shows Al-O reaction in LF is far away from equilibrium, but it is perfect agreement with the computing results when taking the activity of Al2.3.as 1 that due to the inclusion component in LF is mainly Al2.3. Besides, with the temperature rise, the sulfur partition ratio increases softly meanwhile the reaction between Al and O is limited to a great degree resulting in the increase a dissolved oxygen in liquid steel that decreases the sulfur partition ratio seriously. As a result, the sulfur partition ratio appears to decrease with temperature increase in Al killed steel.

关键词： LF refining desulfurization deoxidation sulfur partition ratio

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2.糖尿病患者卒中预防及血糖管理专家共识

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中华内科杂志 2024年第7期63卷 649-659页

作者：《2.糖尿病患者卒中预防及血糖管理专家共识》编写委员会陈莉明母义明不详天津医科大学朱宪彝纪念医院内分泌科天津300134 解放军总医院第一医学中心内分泌科北京100853

糖代谢异常与卒中关系密切,对卒中的发生、发展及预后均有不良影响。良好的血糖控制对改善卒中预后具有重要意义。部分降糖药物能够减少2.糖尿病患者卒中的发生及复发风险。2.糖尿病合并卒中患者应控制血压、血脂,合理应用抗血小板药... 详细信息

糖代谢异常与卒中关系密切,对卒中的发生、发展及预后均有不良影响。良好的血糖控制对改善卒中预后具有重要意义。部分降糖药物能够减少2.糖尿病患者卒中的发生及复发风险。2.糖尿病合并卒中患者应控制血压、血脂,合理应用抗血小板药物。共识专家组基于循证医学证据和临床实践,并经过多次讨论最终形成本共识,以期为临床提供参考。

关键词：糖尿病 2. 卒中预防血糖管理专家共识

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Discovery of double-peaking potassic volcanic rocks in Langshan group of the Tanyaokou hydrothermal- sedimentary deposit, Inner Mongolia, and its indicating significance

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Science China Earth Sciences 2005年第6期48卷 822-833页

作者： PENG Runmin1, ZHAI Yusheng1, WANG Zhigang2.& HAN Xuefeng2.1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology, Ministry of Education, China University of Geosciences, beijing 100083. China 2. Inner Mongolia Geological Prospecting Institute, Ministry of Chemical Industry, Hohhot 010074, China Correspondences should be addressed to Peng Runmin 1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology Ministry of Education China University of Geosciences 100083 Beijing China 2. Inner Mongolia Geological Prospecting Institute Ministry of Chemical Industry 010074 Hohhot China

It is revealed that the protolith of gray-light brown potash-feldspar-leucogranulites and granulites in the 2.d formation of the LG in Tanyaokou deposit are quartz kerotophyre of synsedimentary eruption based on the following facts and features: (1) The rocks look compact and homogeneous without obvious crystals with naked eyes; (2. they contain blastoporphyritic or glomeroporphyritic and blasto-crystalloclastic crystals consisting of quartz with wavy extinction and albite with obvious alteration and deformation; (3. they also contain radiated and fibrous blasto-microspherulitic texture and swallow-tailed bifurcate and blasto-hollow-skeleton crystal texture, representing the rapid cooling characteristic of the magma during submarine volcanic eruption; (4) the major chemical compositions of the rocks are: SiO2.= 70.80%―76.00%, K2. (4.83.―6.2.%)>Na2.(2.78%―3.80%), and K2.+Na2. = 8.63.―9.00%; and (5) their petro-chemical diagrams indicate that they are volcanic rocks. Together with the characteristic that they occur in the same sequence with potassic spilite (SiO2.= 46.12.―50.68%, K2. = 4.2.0}―5.93.>Na2. = 2.15%―3.14%, K2.+Na2. = 6.51%―8.08%), it can be confirmed that the vol-canics occurring in the 2.d Formation of the LG in Tanyaokou district are double-peaking potas-sic volcanic rocks. The discovery, together with the tuffs with ore minerals and the distribution of lead isotopic as well as the value of Co/Ni of pyrites >1 showing the obvious endogenic metali-zation, can prove that the Tanyaokou deposit is an untypical SEDEX-type deposit formed in the extension fault basin in the Mesoproterozonic aulacogen of the northern margin of the north China Platform, and its metallogenesis is related to the synsedimentary volcanic activities and the hydrothermal exhalation, and both the ore-forming material source and volcanics came from mantle or lower crust. These facts mentioned above, together with the meta-volcanic rocks (double-peaking) found in the Dongshengmiao and Huog

关键词： extensional rift basin, double-peaking potassic volcanic rocks, Mesoproterozoic, the 2.d formation of LG, Tanyaokou deposit, Inner Mongolia.

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Engineering coordinate system for vertical mine region based on GPS technique

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中国有色金属学会会刊：英文版 2005年第S1期15卷 225-229页

作者： LU Xiu-shan~1, ZHANG Dong-jian~2. ZHEN Zuo-ya~3. HAN Xiao-dong~1, GUO Heng-qing~2.(1. School of Geoscience and Technology, Shandong University of Science and Technology, Tai’an 701019, China 2. Yanzhou Coal Industry group Company, Ji’ning 2.2.00, China 3. Shanghai Astronomical Observatories, Chinese Academy of Sciences, Shanghai 2.003., China) Shandong Univ Sci & Technol Tai An 701019 Peoples R China Yanzhou Coal Ind Grp Co Jining 272100 Peoples R China Chinese Acad Sci Shanghai Astron Observ Shanghai 200030 Peoples R China

For the problems existing in control network of vertical mine region established by conventional way, this paper advances a new scheme of establishing engineering coordinate system for vertical mine region. Based on the GPS positioning technique, through the relationship of coordinate transformation about a group of connecting points, the transforming parameters between the WGS-84 system and the beijing54 system or Xi’an80 system about the region were calculated. The plane coordinate systems about the region can be maintained with a few of GPS control points using the method of GPS level, and fits the quasi-geoid about the region based on the Ellipsoid WGS-84. Huanghai Vertical Datum 1985 about the region can be maintained with the Ellipsoid WGS-84 as datum plane. Practice proves that there are advantages using the scheme to establish engineering coordinate system: the coordinate system as engineering foundation for vertical mine region will be in preservation for a long time; it is convenient and easy to carry out daily surveying work based on this coordinate system.

关键词： coordinate system control network GPS positioning GPS level quasi-geoid

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A new type of Shipboard Meteorological Satellite Receiving-processing System

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Acta Oceanologica Sinica 2000年第1期19卷 35-46页

作者： Xie Simei Hao Chunjiang Zou Bin Jing Qiyi Liao Xiaohong Sheng Xiaowen Zhang Canrong (1. National Research Center for Marine Environment Forecasts, beijing 100081, China 2. Second Institute of China Aerospace corporation {2. beijing Chuanyi Electric Compan Natl. Res. Ctr. Mar. Environ. F. Beijing 100081 China Second Inst. of China Aerosp. Corp. China beijing Chuanyi Electric Company Chinese Academy of Sciences Beijing China

The Shipboard Meteorological Satellite Receiving-processing System (SMSRPS) is specially developed for the navigation meteorological safeguard of the Antarctic exploration ship over the sea ice area of the forth Ocean. This system can suit to the climate environment of very high temperature high moisture and very low temperature - supersaturation; it has a self-protection ability to against the hurricane - force wind over force 12.and the strong vibration during icebreaking, as well as strong magnetic disturbance. It has two sets of receiving-imagery processing systems for polar orbit low-resolution and quasi-stationary high-solution satellites. The key creation Points of this system are as follows: 1. the active gyro-control stabilization platform and a mixed mounting system of three rotating a - B and x -- y axes are used. It solved the tracing difficulties both in the low elevation angle and very high elevation angle of polar-orbit satellite, even in the status of ship moving with continuously changing its poition, direction and ship roll and pitch. 2. Imagery processing subsystem. The newest BORLAND-- DELPHI language and PASCAL language pro gramming software are used under WINDOWS 95 environment. It has a dynamic positioning nested-grid system and electric mapping grid data system. It can show the latitude-longitude of any point on the map, and marks any object such as ship, station or island, and draws the route. It can monitor cloud and temperature, forest fire, anomalous change of ocean and land. It can output satellite cloud maps of 2. bit with very high clarity. This system is very advanced in technique for the whole structure with the features of small volume, light weight and very low cost. It suits to very bad climate and ocean environment. Its imagery process ing system has complete functions with high resolution and being very easy to operate. It is not only suit to land use, but also and specially to all kinds of ship over the sea. It can be exte

关键词： Shipboard Meteorological Satellite Receiving-processing System imagery processing system active gyro-control platform

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