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Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW china: Evi- dence from clinopyroxene exsolution in garnet

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science china {2. sciences 2005年第7期48卷 1000-1010页

作者： LIU Liang1,3. CHEN Danling1, ZHANG Anda1, SUN Yong1, WANG Yan1, YANG Jiaxi1,2.& LUO Jinhai1 1. Key Laboratory of Continental Dynamics of the Ministry of Education of china, Northwest university, xi’an 710069, china 2. college of earth science and land Resources, chang’an university, xi’an 710054, china 3. The Laboratory of Orogen and Basin of the Ministry of Education, Peking university, Beijing 100871, china Key Laboratory of Continental Dynamics Ministry of Education of China Northwest University Xi'an 710069 China Laboratory of Orogen and Basin Ministry of Education Peking University Beijing 100871 China college of earth {2. and {3. Resources Chang'an University Xi'an 710054 China

The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW china. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1) before exsolution has a maximum Si content of 3.061 per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1000℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the continental lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the continental crust, and such deep- subduction probably reaches to >2.0 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western china.

关键词： Altyn Tagh gneissic K-feldspar (-bearing) garnet clinopyroxenite clinopyroxene exsolution in garnet ultra-high pressure metamorphism.

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Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2. GUO Zeng-zhang1, 2. WU Li-xin3. ZHANG Qin4 1. School of Survey and land Information Engineering, Henan Polytechnic {3., Jiaozuo 454003.{2. 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic {3., Jiaozuo 454003.{2. 3. college of Resources and Civil Engineering, Northeastern {3., Shenyang 110819,{2. 4. college of Geology Engineering and Geomatics, chang’an university,{13.,{2. [a] School of Survey and land Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China [c] college of Resources and Civil Engineering Northeastern University Shenyang 110819 China [d] college of Geology Engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

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High temperature polyimide nanocomposites containing twodimensional nanofillers for improved thermal stability and capacitive energy storage performance

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Nano Research 2024年第8期17卷 7746-7755页

作者： Ding Ai Yuting Han Zongliang xie xi Pang Yuan chang He Li Chenglong Wu Yonghong Cheng Guanglei Wu State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Materials for Energy and Environment State Key Laboratory of Bio-Fibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Future electronic devices toward high integration and miniaturization demand reliable operation of dielectric materials at high electric fields and elevated ***,the electrical deterioration caused by Joule heat generation remains a persistent challenge to ***,the solution-processed polyimide(PI)nanocomposites with unique two-dimensional(2.)alumina nanoplates are *** improvements in the breakdown strength,charge–discharge efficiency and discharged energy density at elevated temperatures have been demonstrated in the composites,owing to simultaneously suppressed conduction loss and increased thermal conductivity upon the incorporation of 2. Al_(2.O_(3. nanofillers possessing excellent dielectric insulation and thermophysical *** predominance of Al_(2.O_(3. nanoplates in enhancing thermal stability and high-temperature capacitive performance over nanoparticles and nanowires is validated experimentally and is further rationalized via finite element ***,the Al_(2.O_(3. nanoplates filled PI nanocomposite exhibits a hightemperature capability up to 2.0℃ and remarkable efficiency(e.g.≥95% at 2.0 MV/m)over a wide temperature range,which outperforms commercial dielectric polymers and rivals the state-of-the-art polyimide nanocomposites.

关键词： capacitors polymer nanocomposites high temperature energy storage thermal stability

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Synthetically adaptive robust filtering for satellite orbit determination

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science china {2. sciences 2004年第7期47卷 585-592页

作者： YANG Yuanxi1 & WEN Yuanlan2.1. xi’an Research Institute of Surveying and Mapping, xi抋’an 710054, china 2. {2. of Aerospace and Material Engineering, National university of Defense Technology, changsha 410073. china 1. xi’an Research Institute of Surveying and Mapping 710054 Xi’an China 2. college of Aerospace and Material Engineering National University of Defense Technology 410073 Changsha China

The quality of the satellite orbit determination is rested on the knowledge of per-turbing forces acting on the satellite and stochastic properties of the observations, and the ability of controlling various kinds of errors. After a brief discussion on the dynamic and geometric orbit determinations, Sage adaptive filtering and robust filtering are reviewed. A new synthetically adaptive robust filtering based on a combination of robust filtering and Sage filtering is *** is shown, by derivations and calculations, that the synthetically adaptive robust filtering for orbit determination is not only robust but also simple in calculation. It controls the effects of the outliers of tracking observations and the satellite dynamical disturbance on the parameter esti-mates of the satellite orbit.

关键词： satellite orbit, Sage filtering, adaptive orbit determination, robust estimation.

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Pb isotope geochemistry of lead, zinc, gold and silver deposit clustered region, Liaodong rift zone,northeastern china

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science china {2. sciences 2005年第4期48卷 467-476页

作者： CHEN Jiangfeng1, YU Gang1, XUE Chunji2. QIAN Hui1, HE Jianfeng1, xiNG Zhi1 & ZHANG Xun1 1. School of earth and Space sciences, {2. of science and Technology of china, Hefei 2.002., china 2. Department of Geology, chang’an university, xi’an 710054, china 1. School of earth and Space sciences University of Science and Technology of China 230026 Hefei China 2. Department of Geology Chang’an University 710054 Xi’an China

Pb isotopic analyses were reported for sulfide and hydrothermal carbonate minerals and marble of the xiquegou lead-zinc, the Zhenzigou zinc-lead and the Gaojiapuzi silver deposits from the Qingchengzi ore field and the Beiwagou zinc-lead deposit in the west, Proterozoic Liaodong rift zone. Pb isotopic ratios of the marble from the Qingchengzi ore field range from 18.2. to 3..63.for 2.6 Pb/2.4Pb, 15.59 to 17.05 for2.7Pb/2.4Pb and 3..43.to 3..63.for 2.8Pb/2.4Pb. The marble gives a Pb-Pb isochron age of 182.±92.Ma, which is interpreted as the age of the metamorphism of the marble. Ore Pb, including Pb of sulfide and hydrothermal car- bonate minerals, from the Qingchengzi ore field shows limited variation with 2.6 Pb/2.4Pb=17.66- 17.96, 2.7 Pb/2.4Pb=15.60-15.74 and 2.8Pb/2.4Pb=3..94-3..60. In contrast, ore Pb from the Beiwagou deposit gives different Pb isotopic ratios with 2.6Pb/2.4Pb=15.68-15.81, 2.7 Pb/2.4Pb= 15.3.-15.45 and 2.8Pb/2.4Pb=3..3.-3..68. Pb of all deposits from the Liaodong rift zone is derived from the upper crust. Ore Pb of the Qingchengzi deposits is derived from a young upper crust. The model Th/U ratios of 4.40 to 4.74 for ore Pb are significantly different from that of 1.7 to 4.4 given by the marble of the Qingchengzi ore field, suggesting that marble is not the source of the ore Pb. Ore Pb of the Beiwagou deposit is extracted from its source and the deposit is formed at the Paleoproterozoic era. Different Pb isotopic ratios of the Qingchengzi ore field and the Beiwagou deposit are due to different ages of the deposits and suggest that the two types of deposits are derived from different sources and are possibly formed by different ore-forming processes.

关键词： Pb isotopes, source(s) of the ore-forming materials, origin of ore deposits, Liaodong rift zone.

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Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china {2. sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2. JIN ZhangDong1 & ZHANG Fei3.1 State Key Laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of sciences, xi’an 710075,{2. 2.Graduate university of the Chinese Academy of sciences, Beijing 100049,{2. 3.college of Resources and Environmental science, Nanjing Agricultural university, Nanjing 2.0095,{2. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate university of the Chinese Academy of sciences Beijing 100049 China college of Resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2. the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3. the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

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Mesozoic subduction-accretion zone in northeastern South china Sea inferred from geophysical interpretations

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science china {2. sciences 2006年第5期49卷 471-482页

作者： ZHOU Di1, WANG Wanyin2. WANG Jialin3. PANG xiong4, CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of sciences, Guang- zhou 5103.1, china 2. college of Geological and Topographical Engineering, chang’an university, xi’an 710054, china 3. Key Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. china 4. china National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, china 5. china National Offshore Oil Co. Limited – Research Center, Beijing 10002., china 1. Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. college of Geological and Topographical Engineering Chang’an University Xi’an 710054 China 3. Key Laboratory of Marine Geology Tongji University Shanghai 200092 China 4. china National Offshore Oil Co. Limited — Shenzhen Branch Shenzhen 518067 China 5. china National Offshore Oil Co. Limited — Research Center Beijing 100027 China

A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South china Sea at approximately NE450 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arcassociated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South china. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South china Sea fills nicely the gapof the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.

关键词： Mesozoic, subduction zone, SE Asia, NE South china Sea, geophysics.

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Extensive identification of landslide boundaries using remote sensing images and deep learning method

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china Geology 2024年第2期7卷 277-290页

作者： chang-dong Li Peng-fei Feng xi-hui Jiang Shuang Zhang Jie Meng Bing-chen Li Faculty of Engineering China University of GeoscienceWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China college of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China

The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster *** is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency ***,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary *** SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic *** exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model *** experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MIoU values between 0.8and 0.9;while 52.images with MIoU values exceeding 0.9,which exceeds the identification accuracy of existing *** work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.

关键词： Geohazard landslide boundary detection Remote sensing image Deep learning model Steep slope Large annual rainfall Human settlements Infrastructure Agricultural land Eastern Tibetan Plateau Geological hazards survey engineering

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The gravitational gradient tensor’s invariants and the related boundary conditions

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science china {2. sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2.3.& ZHAO DongMing4 1 college of earth {2., Graduate university of Chinese Academy of {2.s, Beijing 100049, china 2.Institute of Geodesy and Geophysics, Chinese Academy of {2.s, Wuhan 43.077, china 3.State Key Laboratory of Astronautic Dynamics, xi’an 710043. china 4 Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. china 1. college of earth {2. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China3. State Key Laboratory of Astronautic Dynamics Xi’an 710043 China4. Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

Here we report new approaches of recovering the earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2.term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2.2.T), which is approximately equivalent to O(T2.. Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 2.0, and the models with regard to effect of J2.term have accuracies of 10-8 and the order can reach up to 2.0.

关键词： the earth’s gravitational field gravitational gravidiometry tensor’s invariant

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Geochemistry of Trace and Rare earth Elements in Red Soils from the Dongting Lake Area and Its Environmental Significance

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Pedosphere 2009年第5期19卷 615-622页

作者： MAO Long-Jiang MO Duo-Wen YANG Jing-Hong SHI Chen-xi college of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 (China) college of Urban and Environmental sciences Peking University Beijing 100871 (China) Department of earth sciences Nanjing University Nanjing 210093 (China)

Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of china were determined to understanding the provenance and weathering characteristics of the red *** results showed similar REE distribution patterns among red soils from the Dongting Lake area,xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess *** patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of *** element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering *** Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake *** weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess *** in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.

关键词： Hunan Province provenance sedimentary processes weathering intensity

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