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Fluid Inclusions and Daughter Minerals of Taibai Gold Deposit, ShaanXi Province, china

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Journal of university of Science and Technology beijing 2001年第1期8卷 6-9页

作者： YulingXie, Jiuhua Xu, Dayi Qian, Jianping Li Resources Engeneering school, university of Science and Technology {2., beijing 100083. china Univ Sci & Technol beijing Resources Engn Sch Beijing 100083 Peoples R China

A discovery of daughter minerals in fluid inclusions of Taibai gold deposit, Shaanxi province has been focused on, which is a unique breccia-cemented gold-bearing system. The breccia zone strikes NWW-SEE, occurring in Devonian strata of Southern Qinling Mountains. The cement is mainly composed of ankerite, pyrite, calcite and quartz, which may be divided into four main tectonic-mineralizing stages. Gold mainly occurs in pyrite and ankerite of stage II and IV. It is found that three types of fluid inclusions can be distinguished: (1) aqueous inclusions (type B); (2. CO2.rich inclusions (type C); (3) daughter minerals-containing inclusions (type A). LRM. (Laser Raman Micro-probe) analyses shows that the content of CO2.occupies 54.4.-70.7% (mole fraction, so as the follows) in vapor phases of different type fluid inclusions. CH4.(5.2.-7.3%) and H2. (6.0%-12.7%) exist in both vapor and liquid phases. Many daughter minerals in fluid inclusions of ankerite and quartz have been found. Several kinds of daughter minerals, including ankerite, pyrite, arsenopyrite and halite, were determined by using SEM (scanning electron microscope)/EDS (energy dispersive spectrometer) technique. EPMA (electron probe micro-analysis) technique was also applied to study the daughter minerals exposed to the surface of polished thin sections.

关键词： daughter minerals fluid inclusions gold deposit breccia

Behavior of Non-metallic Inclusions in Centrifugal Induction Electroslag Castings

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Journal of university of Science and Technology beijing 2001年第2期8卷 91-94页

作者： Xichun Chen, Jie Fu, Deguang Zhou, Weiguo Xu (Metallurgy school, university of Science and Technology {2., beijing 100083. china) Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

In order to know the behavior of non-metallic inclusions in centrifugal induction electroslag castings (CIESC), non-metallic inclusions in 5CrMnMo and 4.r5MoSiV1 were qualitatively and quantitatively analyzed. The largest size of inclusions in the casting and the thermodynamic possibility of TiN precipitation in steel were also calculated. The results show that sulfide inclusions are evenly distributed and the content is low. The amount of oxide inclusions in CIESC: 4.r5MoSiV1 steel is close to the ESR steel and lower than that in the EAF steel, and there are some differences along radial direction. Nitride inclusions are fine and the diameter of the largest one is 3-1 mum. With the increase of the centrifugal machine's rotational speed, the ratio of round inclusions increases and the ratio of sharp inclusions decreases. According to the experiment and the calculation results, it is pointed out that the largest diameter of non-metallic inclusions in the CIESC 4.r5MoSiV1 casting is only 6.6 mum, and [N%][Ti%] in 4.r5MoSiV1 steel should be controlled less than 4.4. 10(-5) in order to further reduce the amount and size of TiN inclusions.

关键词： centrifugal induction electroslag casting non-metallic inclusions 4.r5MoSiV1 steel 5CrMnMo steel TiN precipitation

Multi-dimensional project management models for mega-construction companies and their applications

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Science china(Technological Sciences) 2011年第S1期54卷 118-124页

作者： LIN ZhengHang 1,2.QIANG MaoShan 1,2.TANG WenZhe 1,2.FAN QiXiang 3 &LIU Qiang 4.1 Institute of Project Management and Construction Technology,Tsinghua university,{2. 100084.china 2.State Key Laboratory of Hydraulic and Engineering,Tsinghua university,{2. 100084.china 3 china Three Gorges Corporation,Yichang 4.3002.china 4.school of Software,Tsinghua university,{2. 100084.china 1. Institute of Project Management and Construction Technology Tsinghua University Beijing 100084 China2. State Key Laboratory of Hydraulic and Engineering Tsinghua University Beijing 100084 China3. China Three Gorges Corporation Yichang 443002 China4. School of Software Tsinghua University Beijing 100084 China

china is undertaking an increasing number of mega-infrastructure projects along with its rapid economic *** participants in these projects,understand how to adapt the proper and efficient management strategies is *** this paper,we propose three distinct models for companies under various background and management requirements,based on sophisticated data analysis and model ***,we successfully committed these models with hydropower development projects and achieved a great progress in enhancing management efficiency.

关键词： project management models mega-construction companies applications hydropower development companies

Stratigraphic thermohistory and its implications for regional geoevolution in the Tarim Basin,NW china

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Science china Earth Sciences 2010年第10期53卷 1495-1505页

作者： WANG TieGuan1,DAI ShiFeng2.LI MeiJun1,ZHANG WeiBiao1,3,Qiu NanSheng1 & WANG GuangLi1 1 State Key Laboratory of Petroleum Resources and Prospecting,china university of Petroleum,{2. 102.4.,china 2.State Key Laboratory of Coal Resources & Safe Mining,china university of Mining & Technology,{2. 100083.china 3 exploration Research Center,exploration & Development Institute,china Petrochemical Corporation,{2. 100083.china 1. State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China2. State Key Laboratory of Coal Resources & Safe Mining China University of Mining & Technology Beijing 100083 China3. Exploration Research Center Exploration & Development Institute China Petrochemical Corporation Beijing 100083 China

Fourteen vitrinite reflectance profiles from the Tarim Basin,NW china,show that the vitrinite reflectance profiles of individual wells follow a faulted and dislocated dual-stage pattern in the eastern section of the Tazhong Uplift and in the Tabei *** reflectance values in these profiles change sharply at the unconformity beneath the Lower Carboniferous Bachu or Upper Devonian Donghetang Formations,where the overlying Triassic to Carboniferous strata are still in a mature phase within the "liquid oil window".However,the underlying Lower Paleozoic reached the overmature phase beyond the "liquid oil window" towards the end of the Silurian,or in the Early Devonian at the *** the vitrinite reflectance profiles are attributed to a continuous,single-stage pattern in the western section of the Tazhong Uplift,in which the Lower Paleozoic is also in an overmature phase,their overmaturity would have been achieved relatively late in geological *** stratigraphic thermohistory has the following implications to regional geoevolution:(1) The overmature Lower Ordovician to Cambrian strata in the eastern section of the Tazhong Uplift and in the Tabei Uplift,as well as in the Manjiaer Depression,could not have acted as the source kitchen for normal oil(so-called black oil);(2. The dissimilarity in vitrinite reflectance profiles between the eastern and western sections of the Tazhong Uplift reveals Early Paleozoic paleotectonic features,i.e.,lower at the east and higher at the west,whereas recent tectonic features formed since the Late Paleozoic are in reverse,i.e.,higher in the east and lower at the west;(3) Reconstruction of the denuded thickness of sediments overlying the Lower Ordovician strata suggests reconsideration on the paleotectonic features in the Tarim Basin;(4. Based on the sustained duration of the "liquid oil window" for overmature source beds,it is predicted that the Suntuoguole Lower Uplift between the Awati and Manjiaer Depressions is a

关键词： vitrinite reflectance profile faulted and dislocated dual-stage pattern paleotectonic features sustained "liquid oil window" period source kitchen

High-sensitivity photovoltage based on the interfacial photoelectric effect in the SrTiO_(3-δ)/Si heterojunction

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2080-2083页

作者： WEN Juan 1,GUO HaiZhong 1,XING Jie 2.Lü HuiBin 1,JIN Kui-Juan 1,HE Meng 1 & YANG GuoZhen 1 1 beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,beijing 100190,{2. 2.school of Materials Sciences and Technology,{2. university of geosciences,beijing 100083.{2. 1. beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China2. School of Materials Sciences and Technology China University of Geosciences Beijing 100083 China

A high sensitivity photovoltaic effect has been observed in a heterojunction composed of n-type wide bandgap oxide SrTiO 3-δ and p-type Si fabricated by laser molecular beam *** responsivity of open-circuit photovoltage can reach 10 4.V/W without any amplification under zero bias for the wavelength range from visible to near infrared light in nW-μW *** attribute the high performance of the photovoltage responsivity to the interfacial photoelectric effects in the SrTiO 3-δ /Si *** the experimental results,some ideas can be generalized to improve photovoltaic efficiency and develop high sensitivity photodetectors with wide bandgap oxide materials and Si.

关键词： SrTiO 3-δ/Si heterojunction interfacial photoelectric effect photovoltage

Role of inositol 1,4.5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2.3,5) Jian GAO~2.Xiao-mei LAN~3 Gang WANG~4.Sheng WEI~4.Rui-ping XIAO~4.Qi-de HAN~32.Department of Pharmacology,school of Chemical Biology & Pharmaceutical Sciences,Capital university of Medical Sciences,beijing 100069,china 3 Institute of Cardiovascular Science at Health Science Center,Peking university beijing 100083.china 4.Institute of Molecular Medicine and College of Life Science,Peking university,beijing 100871,china Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular Science at Health Science Center Peking University Beijing 100083 China Institute of Molecular Medicine and College of Life Science Peking University Beijing 100871 China

Aim:Intracellular Ca2.plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4.5-trisphosphate receptors（IP3Rs）in the media-tion of cardiac intracellular Ca2.and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3Rsmay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2.sparkoccurrence and global Ca2.***,we hypothesized that Ca2.releasethrough IP3Rs was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4.5-trisphosphate hexakis（butyryloxymethyl）ester（IP3BM）,a membrane-permeant ester of IP3,to activate IP3Rs directly,and Fluo 4.AM tomeasure intracellular Ca2.***:IP3BM(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2.spark release（especially in the perinuclear area）and global Ca2.*** importantly,IP3R inhibitors,2.aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3BM-induced Ca2.responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3H]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（4. h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3R signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4.5-trisphosphate receptors Ca2.sparks α1 adrenergic stimulation cardiac hypertrophy

Dissolving of Nb and Ti carbonitride precipitates in microalloyed steels

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Journal of university of Science and Technology beijing 2003年第5期10卷 78-80页

作者： Wenjin Nie, Shanwu Yang, Shaoqiang Yuan, and Xinlai HeMaterials Science and Engineering school, university of Science and Technology {2., beijing 100083. china Materials Science and Engineering school University of Science and Technology Beijing Beijing 100083 China

The dissolving behaviour of Nb and Ti carbonitride precipitates inmicroalloyed steels during isothermal holding at 1300℃ was investigated by Transmission electronmicroscopy (TEM) and energy dispersion x-ray spectrum (EDX). It was found that all precipitates inNb-Ti microalloyed steel are (Nb, Ti)(C, N). With holding time increasing, the atomic ratio of Nb/Tiin precipitates decrease gradually. These precipitates still existe even after holding for 4. h at1300℃ while Nb(C, N) precipitates dissolve away in Nb microalloyed steel only after 4.h at the sametemperature. These results show that formation and thermostability of precipitates are considerablyinfluenced by interaction between Nb and Ti.

关键词： dissolving (Nb, Ti)(C, N) TEM EDX

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. Institute of geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, {2. 100101, china 2. Graduate school of the Chinese Academy of Sciences, {2. 100039, china 3. College of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, china 4. The Ministry of Science and Technology, P. C. china, {2. 100862. china 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 61004., china 1. Institute of geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of Sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.4.%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Thermodynamic conditions of framework grain dissolution of clastic rocks and its application in Kela 2.gas field

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Science china Earth Sciences 2005年第1期48卷 21-31页

作者： LAI Xingyun, YU Bingsong, CHEN Junyuan, CHEN Xiaolin, LIU Jianqing, MEI Mingxiang, JING Weiguang & CHENG Suhua school of Earth Sciences and Mineral Resources, china {2. of geosciences,{4. Key Laboratory of Lithospheric Tectonics, Deep-level Process and exploration of Ministry of Education,{4. 1. china university of {2.sciences School of Earth Sciences and Mineral Resources 100083 Beijing China 2. Key Laboratory of Lithospheric Tectonics Deep-level Process and Exploration of Ministry of Education 100083 Beijing China

Feldspar and clastic debris are the most important constituent framework grains of sedimentary clastic rocks and their chemical dissolution plays an essential role in the formation and evolution of the secondary pore in the reservoir rocks. On the basis of thermodynamic phase equilibrium, this study investigates the chemical equilibrium relationships between fluid and various plagioclase and K-feldspar in diagenesis of the sediments, particularly, the impact of temperature and fluid compositions (pH, activity of K+, Na+, Ca2. and so on) on precipitation and dissolution equilibria of feldspars. Feldspar is extremely easily dissolved in the acid pore water with a low salinity when temperature decreases. The dissolution of anorthite end-member of plagioclase is related to the Ca content of the mineral and the fluid, higher Ca either in the mineral or in the fluid, easier dissolution of the feldspar. Moreover, the dissolution of albite end-member of plagioclase is related to Na of both the mineral and fluid, lower Na out of both the mineral and fluid, easier dissolution of the mineral. Similarly, lower-K fluid is more powerful to dissolve K-feldspar than the higher. The anorthite component of plagioclase is most easily dissolved in ground water-rock system, the albite is the secondary, and K-feldspar is the most stable. Selective dissolution of plagioclase occurs in diagenesis because of the plagioclase solid solution that is mainly composed of albite and anorthite end-members, Ca-rich part of which is preferentially dissolved by the pore water, in contrast to the Na-rich parts. Based on investigation of reservoir quality, secondary pore, dissolution structures of feldspar, clay minerals and ground water chemistry of the Kela 2.gas field of Kuqa Depression in the Tarim basin of Western china, we discovered that the secondary pore is very well developed in the highest quality section of the reservoir, and the plagioclase of which was obviously selectively dissolved, in c

关键词： dissolution of feldspar, thermodynamic conditions, groundwater pore chemistry, Kela 2 gas field.