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Ultrahigh-pressure metamorphism in the forbidden zone:the Xugou garnet peridotite,Sulu terrane,eastern china

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Ultrahigh-pressure metamorphism in the forbidden zone:the Xu...

中国科学院地质与地球物理研究所2.03.术年会

作者： R.Y.ZHANG,~1 J.G.LIOU,~1 J.S.YANG~2.AND K.YE~3.1 Department of Geological and Environmental Sciences,Stanford university,CA,943.5,USA 2.Institute of Geology,chinese academy of Geological Sciences,Beijing 10003.,{3. 3.Institute of Geology and Geophysics,chinese academy of Sciences,PO Box 982.,Beijing 10002.,{3.

The Xugou garnet peridotite body of the southern Sulu ultrahigh-pressure(UHP) terrane is enclosed in felsic gneiss,bounded by faults,and consists of harzburgite and lenses of garnet clinopyroxenite and *** peridotite is composed of variable amounts of olivine(Fo,enstatite(En),garnet (AlmPrpKnrGrs),diopside and rare *** ultramafic protolith has a depleted residual mantle composition,indicated by a high-Mg number,very low CaO,AlO and total REE contents compared to primary mantle and other Sulu *** garnet(Prp) clinopyroxe-nites are *** for rare kyanite-bearing eclogitic bands,most eclogites contain a simple assemblage of garnet(AlmPrpGrs) + omphacite(Jd) + minor *** and eclogite exhibit LREE-depleted and LREE-enriched patterns,respectively,but both have flat HREE *** La,Sm and Yb contents indicate that both eclogite and garnet clinopyroxenite formed by high-pressure crystal accumulation(+ variable trapped melt) from melts resulting from two-stage partial melting of a mantle source. Recrystallized textures and P-T estimates of 780-870℃,5-7 GPa and a metamorphic age of 2.0}±11 Ma indicate that both mafic and ultramafic protoliths experienced Triassic UHP metamor-phism in the P-T forbidden zone with an extremely low thermal gradient(<5℃km),and multistage retrograde recrystallization during *** of prehnite veins in clinopyroxenite,eclogite, felsic blocks and country rock gneiss,and replacements of eclogitic minerals by prehnite,albite,white mica,and K-feldspar indicate low-temperature metasomatism.

关键词： forbidden zone garnet peridotite low-temperature metasomatism Sulu terrane ultrahigh-pressure metamorphism

岩溶生态系统土壤及表生植被某些特性变异与石漠化的相关性

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土壤学报 2004年第2期41卷 196-202页

作者：李阳兵谢德体魏朝富中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550002 西南农业大学资源环境学院重庆400716

岩溶山地石漠化是一种与脆弱生态地质背景和人类活动相关联的土地退化过程。本文以重庆市典型岩溶山地为例 ,探讨了岩溶生态系统土地利用方式与土壤机械组成、土壤水稳性团聚体、土壤有机质、土壤种子库、植被类型的关系。结果表明 ,经... 详细信息

岩溶山地石漠化是一种与脆弱生态地质背景和人类活动相关联的土地退化过程。本文以重庆市典型岩溶山地为例 ,探讨了岩溶生态系统土地利用方式与土壤机械组成、土壤水稳性团聚体、土壤有机质、土壤种子库、植被类型的关系。结果表明 ,经开垦利用后 ,岩溶环境土壤表层砂化现象更加明显。土地利用强度越大 ,对土壤团粒结构的破坏也越大 ,林地、灌草坡对水分的保持能力强 ,土地利用强度较大的土壤保水能力相对较弱 ,土壤有机质受土地利用强度的明显影响。土地利用强度越大 ,木本植物种子越少 ,草本植物种子越多 ,且以农田杂草为主。土地利用方式的变化 (如陡坡开垦 )是对次生植被及其种子库的主要威胁。

关键词：岩溶生态系统土壤表生植被石漠化土地退化土地利用方式土壤种子库

Study on High Cutting Slopes with Horizontal Soft-hard Strata in Three Gorges Reservoir Area

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Study on High Cutting Slopes with Horizontal Soft-hard Strat...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Guoxiang Yang~(1,a),Jinyu Dong~(2.b),Faquan Wu~(1,c),Dong Wang~(1,d), Jihong Yang~(2.e) 1 Institute of Geology and Geophysics,chinese academy of Sciences Key Laboratory of Geomechanics,Institute of Geology and Geophysics,chinese academy of Sciences Beijing 10002.,china 2.North china university of Water Resources and Electric Power,Zhengzhou 450011,china

High cutting slopes with nearly horizontal soft-hard alternant strata are widely distributed in three gorges reservoir area,the soft and hard rocks are mainly mud stone and sandstone of Jurassic *** failure of this kind of slope is also the main geo-hazards in this ***,this paper analyzed the impact of topography,water as well as the differential weathering and combination characteristics of soft and hard rocks *** the sliding failure of slopes;secondly, sliding failure modes of this kind of slope were classified into four types including circular sliding, sliding along the extroversion structural surface,sliding along the mudded intercalation and wedge sliding,they were analyzed combined with case *** lastly,support methods against the certain failure mode were put *** research results are significant to the support and treatment of high cutting slopes in Three gorges area.

关键词： high cutting slope soft-hard alternant strata sliding failure mode protection measures

Genesis of Coal Metamorphism of Late PalaeozoicCoals in the South of North china——A Further Approach to the Effects of ThermalGroundwater on Coal Metamorphism

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Acta Geologica Sinica(English Edition) 1995年第2期69卷 183-195页

作者： Zhong NingningJianghan Petroleum Institute, Shashi City, Hubei and Cao DaiyongBeijing graduate School, china {2. of Mining and Technology, Beijing Jiang Minxi Jianghan Petroleum Institute Shashi Hubei China

The close relationship between the genesis of coal metamorphism and the evolution of the regional tectonic framework is expounded on the basis of an analysis of the geological factors causing the metamorphic zonation of the Late Palaeozoic coals in southern North china; in terms of the mechanism for the formation of palaeogeothermal anomalies, the effects of thermal groundwater on coal metamorphism is highlighted and a geological model for thermal groundwater metamorphism of coal established; with the concept of the palaeogeotherm-coal metamorphism system, the genesis of coal metamorphism is analysed according to the distribution pattern of three geological factors: heat source, heat-carrier and channel, and heat-collector.

关键词： coal metamorphism thermal evolution of organic mattern thermal groundwater palaeogeothermal anomaly palaeogeothermal-coal metamorphism system. Late Palaeozoic coal-bearing series

Geomagnetic anomalies recorded in L9 of the Songjiadian loess section in southeastern chinese Loess Plateau

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Geomagnetic anomalies recorded in L9 of the Songjiadian loes...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： WANG DaoJing~(1*),WANG YongCheng~2.HAN JingTai~1,DUAN MuGang~3.SHAN JiaZeng~1 & LIU TungSheng~1 1 Key Laboratory ofCenozoic Geology and Environment,Institute of Geology and Geophysics,chinese {2. of Sciences,Beijing 10002.,china 2.china university ofGeosciences,Beijing 100083.china 3.School of Information Science and Technology,Beijing Institute of Technology,Beijing 100081,china

Detailed magnetostratigraphic and rock magnetic investigations on L8-S12.of the Songjiadian loess section in the Sanmenxia area, southernmost margin of the chinese Loess Plateau were conducted in this ***/Brunhes(M/B) boundary occurred at the bottom of the loess unit *** top and bottom boundaries of the Jaramillo polarity subchron are found in the middle of L10 and the bottom of L12.*** fabric of the loess layers maintains the original depositional features and the recorded remanent magnetization analysis indicates little post-deposition disturbance *** late Matuyama chron,two anomalies of geomagnetic field have been detected in *** data demonstrated that these recorded anomalies were less likely a result of remagnetization,but more possibly the signature of geomagnetic excursions occurred,named SJD1 and *** is calculated that the midpoint ages of SJD1 and SJD2.are 0.917 Ma and 0.875 Ma,respectively,and the time-interval between the two events approximates 12.***,SJD1 is close to the Santa Rosa(0.92. Ma) and SJD2.corresponds to the Kamikatsura (0.886 Ma) *** consistence with previous studies,the geomagnetic field was weakened during these events.

关键词： Paleomagnetism polarity event loess Sanmenxia

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阴极射线激发下新型蓝粉的研制

中国稀土学报 2002年第6期20卷 612-615页

作者：邹开顺李岚徐征张晓松孙力熊光楠天津理工学院材料物理研究所天津300191 北方交通大学光电子技术研究所北京100044

蓝色荧光粉在高密度激发下的衰减与饱和是影响显示器整体性能的因素之一,我们研制的阴极射线新型蓝粉ZnS∶Zn,Pb具有优异的高密度激发特性和较好的饱和特性。本文分析了制备条件对ZnS∶Zn,Pb发光性能的影响;同时注意到ZnS∶Tm2.发宽谱... 详细信息

蓝色荧光粉在高密度激发下的衰减与饱和是影响显示器整体性能的因素之一,我们研制的阴极射线新型蓝粉ZnS∶Zn,Pb具有优异的高密度激发特性和较好的饱和特性。本文分析了制备条件对ZnS∶Zn,Pb发光性能的影响;同时注意到ZnS∶Tm2.发宽谱带蓝光有很高的亮度和效率,研究了在ZnS∶Zn,Pb中掺入Tm2.的发光情况,发现阴极射线激发下相对发光亮度有了进一步提高,并具有较好的亮度饱和特性,随着Tm2.浓度的增加,光谱的主峰发生了蓝移,相对发光亮度有所提高,非线性有所改善,改进后的荧光粉可应用于FED,PTV等显示器中。

关键词：阴极射线硫化锌稀土蓝粉谱峰蓝移荧光粉铥

Analysis and Modeling of GLONASS Broadcast Ephemeris Errors

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Analysis and Modeling of GLONASS Broadcast Ephemeris Errors

第三届中国卫星导航学术年会

作者： ZHANG ChenXi 1,2.WANG QianXin 2.DANG YaMin 2.Yu ZhiGang 1(1.Shangdong university of Science and Technology,Qingdao,2.6510 2.chinese {2. of Surveying & Mapping,Beijing,10083.)

One of the most problems in GNSS application is to obtained high precision *** this paper,the error characters of GLONASS broadcast ephemeris （GBE） are analyzed *** week data of all healthy orbiting satellites from GBE are calculated and their errors are figured *** result shows that there are some obvious periodic varieties in the errors of ***,the main periods can be obtained by FFT and spectrum analysis.A new compensation model has been *** verify the validation of the model,an experiment is done with GBE data of 7 *** results show that the proposed model can improve the precision of GBE by 2.3.times,even 7-8 *** is very important to improve the precision of GLONASS real time ***,this method can also be applied to COMPASS.

关键词： GLONASS broadcast ephemerides precise ephemerides spectrum analysis.

生活污泥堆肥氮磷矿化特性及对芹菜生长的影响

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土壤通报 2009年第4期40卷 833-837页

作者：杨丽标张丽娟邹国元崔希龙河北农业大学资源与环境科学学院河北保定071000 北京市农林科学院植物营养与资源研究所北京100097 北京城市排水集团有限责任公司北京100038

利用盆栽试验研究了4个施肥水平条件下污泥堆肥单施(S)、污泥堆肥—尿素配施(S+U)以及尿素单施(U)三因素对芹菜产量、土壤肥力性状的影响,同时研究了污泥堆肥的氮、磷矿化和供应特点。结果表明,与对照相比,不同用量的尿素单施没有显著... 详细信息

利用盆栽试验研究了4个施肥水平条件下污泥堆肥单施(S)、污泥堆肥—尿素配施(S+U)以及尿素单施(U)三因素对芹菜产量、土壤肥力性状的影响,同时研究了污泥堆肥的氮、磷矿化和供应特点。结果表明,与对照相比,不同用量的尿素单施没有显著提高芹菜产量,而施用污泥堆肥条件下,无论是单施还是配合尿素施用均显著增加了芹菜产量,单施污泥堆肥增产幅度为12.6%～3..0%,污泥堆肥配合尿素施用增产幅度为14.2.～18.2.。随着污泥堆肥、尿素等肥料用量的增加,芹菜硝酸盐含量显著增加。在单施条件下,污泥堆肥氮、磷矿化率分别为15.43.～2..75%和1.3.%～7.2.%,在配施尿素条件下,污泥堆肥氮、磷矿化率分别为13.16%～2..3.%和1.2.%～7.3.%。在施氮量为0.15～0.3.gkg-1土壤时,等氮量施用条件下,氮肥利用率表现为S>S+U>U。施用污泥堆肥可以较大幅度地提高土壤速效氮、磷的含量,同时导致土壤pH值下降,大量施用也会引起土壤盐分的累积。

关键词：污泥堆肥芹菜氮磷矿化产量

Use of the advanced microwave sounding unit data to improve typhoon prediction

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Progress in Natural Science:Materials International 2009年第3期19卷 369-376页

作者： Guo Deng a,*, Dalin Zhang b, Tong Zhu c, Angsheng Wang d a National Meteorological Center, Beijing 100081, china b Department of Atmospheric and Oceanic Science, university of Maryland, Maryland 2.742. USA c Cooperative Institute for Research in the Atmosphere, Colorado State university, Colorado 8052.3} USA d Institute of Atmospheric Physics, {3. academy of Sciences, Beijing 10002., china [a]National Meteorological Center Beijing 100081 China [b]Department of Atmospheric and Oceanic Science University of Maryland Maryland 20742 USA [c]Cooperative Institute for Research in the Atmosphere Colorado State University Colorado 80523 USA [d]Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The effects of incorporating the advanced microwave sounding unit (AMSU-A) data with a modified Zhu-Zhang-Weng vortex- bogussing algorithm on typhoon prediction are examined through the use of the PSU/NCAR Mesoscale Model version 5 (MM5). The AMSU-A data contain the vertical distribution of the retrieved temperature from satellite brightness temperature, with the geopo- tential height and wind fields derived through a series of statistical and diagnostic calculations. The advantages of the modified vortex- bogussing algorithm include the incorporation of realistic asymmetric typhoon structures, the balanced dynamics with the background field, the easiness to implement and the effcient computations. To test the effciency of this vortex-bogussing algorithm, the Typhoon Dan event in 1999 is simulated by incorporating the derived AMSU-A fields into the initial conditions of the MM5 modeling system. Results show significant improvements in the track and intensity of the storm, as compared to the simulation without the AMSU-A data. Therefore, this modified vortex-bogussing algorithm can be easily implemented on any typhoon modeling system, which will improve the real-time forecast of tropical cyclones.

关键词： AMSU Satellite retrieval Typhoon prediction