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| 1 | Overtopping breaching of cohesive homogeneous earth dam with different cohesive strength显示文摘In consideration of the range of clay content of Chinese earth dams, the world's highest prototype tests have been made to research on the effects of cohesive strength of filling of cohesive homogeneous earth dam on breach formation. Three breach mechanisms were presented, they were the source-tracing erosion of dam body with the form of 'multilevel headcut', 'two-helix flow' erosion of dam crest and collapse of breach sidewalls due to instability. It can be concluded that the cohesive strength of filling of earth dam has great effect on breach formation. When the cohesive strength is bigger, the breach process becomes slower, and the peak outflow and the final width and depth of breach become smaller. The main character of the breach formation is head cutting and dumping collapse. When the cohesive strength is smaller, the breach process becomes faster, and the peak outflow, the final width and depth of breach become bigger. The main character of the breach formation is single level head cutting and shearing collapse. | ZHANG JianYun LI Yun XUAN GuoXiang WANG XiaoGang LI Jun | 2009 | Science China(Technological Sciences)2009，52，10： | 34 |
| 2 | Barometric altimetry system as virtual constellation applied in CAPS显示文摘This work describes the barometric altimetry as virtual constellation applied to the Chinese Area Positioning System (CAPS), which uses the transponders of communication satellites to transfer navigation messages to users. Barometric altimetry depends on the relationship of air pressure varying with altitude in the Earth’s atmosphere. Once the air pressure at a location is measured the site altitude can be found. This method is able to enhance and improve the availability of three-dimensional positioning. The difficulty is that the relation between barometric pressure and altitude is variable in different areas and under various weather conditions. Hence, in order to obtain higher accuracy, we need to acquire the real-time air pressure corresponding to an altimetric region’s reference height. On the other hand, the altimetry method will be applied to satellite navigation system, but the greatest difficulty lies in how to get the real-time air pressure value at the reference height in the broad areas overlaid by satellite navigation. We propose an innovational method to solve this problem. It is to collect the real-time air pressures and temperatures of the 1860 known-altitude weather observatories over China and around via satellite communication and to carry out time extrapolation forecast uniformly. To reduce data quantity, we first partition the data and encode them and then broadcast these information via navigation message to CAPS users’ receivers. Upon the interpolations being done in receivers, the reference air pressure and temperature at the receiver’s nearby place is derived. Lastly, combing with the receiver-observed real air pressure and temperature, the site’s altitude can be determined. The work is presented in the following aspects: the calculation principle, formulae, data collection, encoding, prediction, interpolation method, navigation message transmission together with errors causes and analyses. The advantages and shortcomings of the technique are discussed at the end. | AI GuoXiang SHENG PeiXuan DU JinLin ZHENG YongGuang CAI XianDe WU HaiTao HU YongHui HUA Yu LI XiaoHui | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 22 |
| 3 | The principle of the positioning system based on communication satellites显示文摘It is a long dream to realize the communication and navigation functionality in a satellite system in the world. This paper introduces how to establish the system, a positioning system based on communication satellites called Chinese Area Positioning System (CAPS). Instead of the typical navigation satellites, the communication satellites are configured firstly to transfer navigation signals from ground stations, and can be used to obtain service of the positioning, velocity and time, and to achieve the function of navigation and positioning. Some key technique issues should be first solved; they include the accuracy position determination and orbit prediction of the communication satellites, the measur- ing and calculation of transfer time of the signals, the carrier frequency drift in communication satellite signal transfer, how to improve the geometrical configuration of the constellation in the system, and the integration of navigation & communication. Several innovative methods are developed to make the new system have full functions of navigation and communication. Based on the development of crucial techniques and methods, the CAPS demonstration system has been designed and developed. Four communication satellites in the geosynchronous orbit (GEO) located at 87.5°E, 110.5°E, 134°E, 142°E and barometric altimetry are used in the CAPS system. The GEO satellites located at 134°E and 142°E are decommissioned GEO (DGEO) satellites. C-band is used as the navigation band. Dual frequency at C1=4143.15 MHz and C2=3826.02 MHz as well as dual codes with standard code (CA code and precision code (P code)) are adopted. The ground segment consists of five ground stations; the master station is in Lintong, Xi’an. The ground stations take a lot of responsibilities, including monitor and management of the operation of all system components, determination of the satellite position and prediction of the satellite orbit, accomplishment of the virtual atomic clock measurement, transmission and receiving navigation signals to and from each satellite. In the north, the south, the east, the west and the center of Chinese main land, the function of CAPS demonstration system is checked and measured. In cars and on board the system is also checked and measured. The results are as follow: CA-code, horizontal positioning accuracy, 15-25 m (1σ), vertical, 1-3 m; P-code, horizontal positioning accuracy, 8-10 m (1σ), vertical, 1-3 m; velocity accuracy, CA-code, 0.13-0.30 m/s, P-code, 0.15-0.17 m/s; time accuracy, CA-code, 160 ns, P-code, 13 ns; determination accuracy of orbit ≤2 m. About 20 million US $ and two years are spent for the development of demonstration. A complete CAPS system is now being established. | AI GuoXiang SHI HuLi WU HaiTao LI ZhiGang GUO Ji | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 21 |
| 4 | A new method for determination of satellite orbits by transfer显示文摘The original idea of a new method for determination of satellite orbits by transfer is from Two-Way Satellite Time and Frequency Transfer (TWSTFT). The original method is called 'determination of satellite orbit by transfer'. The method is not only for determination of satellite orbit but also for the time transfer with high accuracy and precision. The advantage is that the accuracy and the precision for determination of satellite orbit are very high and the new method is favorable for various applications. The combination of various signals disseminated and received forms various modes of satellite orbit determinations. If receivers at stations receive the own station-disseminated signals via a satellite transponder, it forms an orbit determination mode called 'receiving the own station-disseminated signals mode'. If receivers at all stations receive the signals disseminated from the master station via satellite transponders, it forms an orbit determination mode called 'receiving the master station-disseminated signals mode'. If all of receivers at stations receive all stations-disseminated signals via satellite transponders, it forms an orbit determination mode called 'receiving all stations-disseminated signals mode'. Also there are other combinations of signals for satellite orbit determination. For dif- ferent orbit determination modes with different signal combinations, their rigorous formulae of proc- essing are hereby presented in this paper. The accurate and the precise satellite orbit determination for both of the modes, 'receiving the own station-disseminated signals mode' and 'receiving the master station-disseminated signals mode' is attempted. It shows that the accuracy and precision for both of modes are nearly the same, the ranging accuracy is better than 1 cm, and the observation residuals of satellite orbit determination are better than 9 cm in the observation duration of 1 day. | LI ZhiGang YANG XuHai AI GuoXiang SI HuLi QIAO RongChuan FENG ChuGang | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 17 |
| 5 | Ground settlement of Chek Lap Kok Airport,Hong Kong,detected by satellite synthetic aperture radar interferometry显示文摘Satellite synthetic aperture radar (SAR) inter-ferometry is used to investigate the slowly accumulating ground settlement at the new Chek Lap Kok Airport in Hong Kong. Most of the land occupied by the airport was reclaimed from the sea and therefore certain ground settlement in the area has been expected. A pair of ERS-2 SAR images spanning nearly a year is used in the study. The high spatial resolution (20 m×20 m) ground settlement map derived indicates that the settlement that occurred in the area over the time period is as large as 50 mm. The SAR measurement results agree with the levelling measurements at some benchmarks in the area to well within 1 cm(rms error),and the overall correlation between the two types of results is 0.89. The paper presents some brief background of inter-ferometric SAR, and outlines the data processing methods and results. | LIU Guoxiang DING Xiaoli CHEN Yongqi LI Zhilin LI Zhiwei | 2001 | Chinese Science Bulletin2001，46，21： | 16 |
| 6 | Early Cambrian Mollusc Watsonella crosbyi:A Potential GSSP Index Fossil for the Base of the Cambrian Stage 2显示文摘软体动物 Watsonella crosbyi 在西伯利亚的站台在东方云南,中国和阿尔丹河河区域的 Pestrotsvet 形成从 Zhujiaqing 形成的更低的寒武纪的 Dahai 成员根据材料被学习。这石块过分地在文学在不同名字下面被描述了,例如 Heraultia varensalensis Cobbold, 1935, H。sibirica Missarzhevsky, 1974, Heraultipegma yunnanensis 他和杨, 1982, H。yannanese 他和杨, 1982, Watsonella yunnanensis, W。crosbyi Grabau, 1900,等等。分类修订证明另外的种类是 W 的年轻同义词。crosbyi。功能的形态学的分析暗示那 W。自从它的 univalved 贝壳是位於腹中的 untorted 并且缺乏坛和真内部 pegma, crosbyi 可以比 rostroconch 是 helcionelloid。在磷酸的内部模子的表面上保存的原来的微观结构的复制品证实壳由二层组成。内部层是 lamello 纤丝状的,并且外部层是 spherulitic 棱柱。在 siliciclastic 和迟了的 Terreneuvian 的碳酸盐岩石的普遍地理出现显示那 W。crosbyi 是为寒武纪的系列 1 的全球关联和分(Terreneuvian ) 的重要索引石块。W 的第一本外观资料(一度时髦的风尚) 。crosbyi 被建议是潜在的 GSSP (全球边界 Stratotype 节和点) 为定义寒武纪的阶段的底的候选人标记 2。 | LI Guoxiang ZHAO Xin Alexander GUBANOV ZHU Maoyan NA Lin | 2011 | Acta Geologica Sinica(English Edition)2011，85，2： | 13 |
| 7 | Methods of rapid orbit forecasting after maneuvers for geostationary satellites显示文摘A geostationary(GEO) satellite may serve as a navigation satellite,but there is a problem that maneuvers frequently occur and the forces are difficult to model.Based on the technique of determining satellite orbits by transfer,a predicted orbit with high accuracy may be achieved by the method of statis-tical orbit determination in case of no maneuver force.The predicted orbit will soon be invalid after the maneuver starts,and it takes a long time to get a valid orbit after the maneuver ends.In order to improve ephemeris usability,the method of rapid orbit forecasting after maneuvers is studied.First,GEO satellite movement is analyzed in case of maneuvers based on the observation from the orbit meas-urement system by transfer.Then when a GEO satellite is in the free status just after maneuvers,the short arc observation is used to forecast the orbit.It is assumed that the common system bias and biases of each station are constant,which can be obtained from orbit determination with long arc observations.In this way,only 6 orbit elements would be solved by the method of statistical orbit determination,and the ephemeris with high accuracy may be soon obtained.Actual orbit forecasting with short arc observation for SINOSAT-1 satellite shows that,with the tracking network available,the precision of the predicted orbit(RMS of O-C) can reach about 5 m with 15 min arc observation,and about 3 m with 30 min arc observation. | YANG XuHai LI ZhiGang FENG ChuGang GUO Ji SHI HuLi AI GuoXiang WU FengLei QIAO RongChuan | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 10 |
| 8 | A comparison of the biological,geological events and environmental backgrounds between the Neoproterozoic-Cambrian and Permian-Triassic transitions显示文摘The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Cambrian Explosion) and the largest mass extinction at the end-Permian.Previous studies suggest that these two critical transitions showed certain comparability in major evolutionary events.In other words,a series of biological,geological,and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T transition.Those events included continental re-configuration related to the deep mantle dynamics,global-scale glaciations,large C-,Sr-,and S-isotope perturbations indicating atmospheric and oceanic changes,abnormal precipitation of carbonates,and associated multiple biological radiations and mass extinctions.The coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth's surface,which in turn caused major biological re-organizations.A detailed comparison of those events during the two critical transitions indicates that despite their general comparability,significant differences do exist in magnitude,duration,and frequency.The supercontinent Rodinia began to rift before the Snowball Earth time.By contrast,the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to Cisuralian.Quantitative data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem disruption.This is indicated by the disappearance of the whole Ediacaran biota at the N-C boundary.The subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ecosystem.However,the end-Permian mass extinction is manifested mainly by the extinction of many different taxa at class and order levels.Although it caused the extinction of 95% of marine species and 75% of terrestrial species as well as complete cessation of coal and reef deposits after the mass extinction,this high-level biological re-organization still occurred within an established ecosystem,however drastic it may seem.Survived or Lazarus taxa re-occupied the existing ecospace in a relatively short duration after the end-Permian mass extinction.C-isotope excursions display large perturbations during both transitions,yet also in different magnitudes and frequencies,which suggest different atmospheric and oceanic conditions.The recurrent geological and geochemical events as well as the coupled major biological turnovers during the two transitions provide new clues to understanding the interplays among the earth-life system.Thus,it is essential to carry out multidisciplinary studies from the deep internal system to the surface of the Earth as a whole in order to unravel the interactions of different spheres of the earth. | ShuZhong Shen MaoYan Zhu XiangDong Wang GuoXiang Li ChangQun Cao Hua Zhang | 2010 | Science China Earth Sciences2010，53，12： | 9 |
| 9 | The wheat MYB-related transcription factor TaMYB72 promotes flowering in rice显示文摘Through large-scale transformation analyses, Ta MYB72 was identified as a flowering time regulator in wheat. Ta MYB72 is a MYB family transcription factor localized to the nucleus. Three Ta MYB72 homologs,Ta MYB72-A, Ta MYB72-B and Ta MYB72-D, cloned from hexaploid wheat were mapped to the short arm of the group 6 chromosomes. Under the long-day conditions,over-expression of the Ta MYB72 in rice shortened the flowering time by approximately 12 d. Expression analyses suggest that Ta MYB72 may function through upregulation of florigen genes Hd3 a and RFT1. | Lichao Zhang Guoxiang Liu Jizeng Jia Guangyao Zhao Chuan Xia Lina Zhang Fu Li Qiang Zhang Chunhao Dong Shuangcheng Gao Longzhi Han Xiuping Guo Xin Zhang Jinxia Wu Xu Liu Xiuying Kong | 2016 | Journal of Integrative Plant Biology2016，58，8： | 8 |
| 10 | Cambrian integrative stratigraphy and timescale of China显示文摘The Cambrian Period is the first period of the Phanerozoic Eon and witnessed the explosive appearance of the metazoans, representing the beginning of the modern earth-life system characterized by animals in contrary to the Precambrian earth-life system dominated by microbial life. However, understanding Cambrian earth-life system evolution is hampered by regional and global stratigraphic correlations due to an incomplete chronostratigraphy and consequent absence of a highresolution timescale. Here we briefly review the historical narrative of the present international chronostratigraphic framework of the Cambrian System and summarize recent advances and problems of the undefined Cambrian stage GSSPs, in particular we challenge the global correlation of the GSSP for the Cambrian base, in addition to Cambrian chemostratigraphy and geochronology. Based on the recent advances of the international Cambrian chronostratigraphy, revisions to the Cambrian chronostratigraphy of China, which are largely based on the stratigraphic record of South China, are suggested, and the Xiaotanian Stage is newly proposed for the Cambrian Stage 2 of China. We further summarize the integrative stratigraphy of South China, North China and Tarim platforms respectively with an emphasis on the facies variations of the Precambrian-Cambrian boundary successions and problems for identification of the Cambrian base in the different facies and areas of China. Moreover, we discuss stratigraphic complications that are introduced by poorly fossiliferous dolomite successions in the upper Cambrian System which are widespread in South China, North China and Tarim platforms. | Maoyan ZHU Aihua YANG Jinliang YUAN Guoxiang LI Junming ZHANG Fangchen ZHAO Soo-Yeun AHN Lanyun MIAO | 2019 | Science China Earth Sciences2019，62，1： | 8 |
| 11 | Medical expenditures for colorectal cancer diagnosis and treatment: A 10-year high-level-hospital-based multicenter retrospective survey in China, 2002-2011显示文摘Objective: Colorectal cancer(CRC) causes a substantial burden of disease in China and the evidence of economic burden triggered is fundamental for priority setting. The aim of this survey was to quantify medical expenditures and the time trends for CRC diagnosis and treatment in China.Methods: From 2012 to 2014, a hospital-based multicenter retrospective survey was conducted in 13 provinces across China. For each eligible CRC patient diagnosed from 2002 to 2011, clinical information and expenditure data were extracted using a uniform questionnaire. All expenditure data were reported in Chinese Yuan(CNY)using 2011 values.Results: Of the 14,536 CRC patients included, the average age at diagnosis was 58.2 years and 15.8% were stageI cases. The average medical expenditure per patient was estimated at 37,902 CNY [95 % confidence interval(95%CI): 37,282-38,522], and the annual average increase rate was 9.2% from 2002 to 2011(P for trend <0.001), with a cumulative increase of 2.4 times(from 23,275 CNY to 56,010 CNY). The expenditure per patient in stages Ⅰ, Ⅱ, Ⅲ and Ⅳ were 31,698 CNY, 37,067 CNY, 38,918 CNY and 42,614 CNY, respectively(P<0.001). Expenditure significantly differed within various subgroups. Expenses for drugs contributed the largest proportion(52.6%).Conclusions: These conservative estimates illustrated that medical expenditures for CRC diagnosis and treatment in tertiary hospitals in China were substantial and increased rapidly over the 10 years, with drugs continually being the main expense by 2011. Relatively, medical expenditures are lower for CRC in the earlier stages. These findings will facilitate the economic evaluation of CRC prevention and control in China. | Jufang Shi Guoxiang Liu Hong Wang Ayan Mao Chengcheng Liu Lanwei Guo Huiyao Huang Jiansong Ren Xianzhen Liao Yana Bai Xiaojie Sun Xinyu Zhu Jialin Wang Bingbing Song Jinyi Zhou Lin Zhu Haike Lei Yuqin Liu Yunyong Liu Lingbin Du Yutong He Kai Zhang Ni Li Wanqing Chen Min Dai Jie He | 2019 | Chinese Journal of Cancer Research2019，31，5： | 8 |
| 12 | Sedimentary Characteristics of the Pleistocene Outwash Accumulation and their Implications for Paleoclimate Change in the Midstream of Dadu River,Southwestern China显示文摘古老的冰川边碛外的沉积累积,与复杂沉积特征在更新世扔了,在 Dadu 河的中流山谷被发现,西南的中国。他们的沉积特征为在这个区域获得深卓见进古气候变化的相关性被调查。这为二代表性的冰川边碛外的沉积累积借助于详细地点调查,采样和实验室测试(谷物尺寸分发和标明日期测试的电子旋转回声) 被完成。基于现在的学习,几个主要结论是如下外面淹死:1 ) 累积主要由粗糙的土壤组成(粗糙的部分是超过 50%) 并且很粗糙的土壤(粗糙的部分关于 20%35% ,并且很粗糙的部分是超过 55%) ;2 ) 粗糙的土壤是排序得好的亚回合和亚 stratified 到成层得好,当粗糙的土壤展出亚回合到亚 angular 时并且糟糕排序;3 ) 累积被要求到间歇地在三个次时期被扔了。这被天气 / 剩余的泥土的二层证实,紫色到在颜色的砖红;并且 4 )在学习区域的温度增加了超过三个次时期,这被推断,即, 280 ka B.P 到 120 ka B.P ,到 80 ka B.P 的 110 ka B.P 和到 25 ka B.P 的 70 ka B.P ,并且分别地在 120 ka B.P 和 77 ka B.P 衰退了两次。 | TU Guoxiang HUANG Runqiu DENG Hui LI Yanrong | 2012 | Acta Geologica Sinica(English Edition)2012，86，4： | 7 |
| 13 | Early Cambrian eodiscoid trilobites of the Yangtze Platform and their stratigraphic implications显示文摘Analysis of the taxonomy and stratigraphic distribution of the Early Cambrian eodiscoid trilobites of the Yangtze Platform indicates that species of Tsunyidiscus and Hupeidiscus can be used for biostratigraphic correlation. T. aclis occurs only in the lower Qiongzhusian, T. armatus occurs in the lower and middle Qiongzhusian, while T. niutitangensis and T. tingi occur mainly in the middle and upper Qiongzhusian, with only T. tingi extending upward into the lower Canglangpuian. H. orientalis first appears in the upper Qiongzhusian, reaching peak abundance in the lower Canglangpuian and becoming extinct above the Drepanuroides Zone. Biostratigraphic and lithostratigraphic correlations indicate that the limestone in the lower part of the Mingxinsi Formation, the Upper Member of Jiumenchong Formation, and the upper part of the Middle Member of the Huangbailing Formation, can be correlated with each other as Hupediscus, an index fossil of the lower Canglangpuian, is abundant in all these units. The lower part of the Niutitang and Jiumenchong formations in eastern Guizhou, which mainly represent Qiongzhusian strata, can be correlated with the Lower Member of the Huangbailing Formation. The basal part of the Niutitang Formation, which may be equivalent to the Upper Meishucunian Shiyantou Formation in eastern Yunnan, is very condensed. Well-preserved sponge faunas and non-mineralized fossils in the lower part of the Niutitang and Hetang formations are not older than Qiongzhusian in age. | YANG Aihua, ZHU Maoyan*, ZHANG Junming and LI Guoxiang(Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China) | 2003 | Progress in Natural Science:Materials International2003，13，11： | 7 |
| 14 | Synthesis of CaCO_3 crystals using hydroxypropylmethyl cellulose hydrogel as template显示文摘Calcium carbonate crystallization was performed in hydrogel of hydroxypropylmethyl cellulose (HPMC). Results showed that the polyhydroxy functionalities in HPMC gel network facilitated the nucleation of aragonite which was not found in experiment without HPMC hydrogel and in experiment using methylcellulose (MC) hydrogel as template. On the other hand, due to the unique assembly of the macromolecules in HPMC hydrogel network, which was different from other hydrogels used in some previous reports, particular crystal morphology, corncob-like CaCO_3, was obtained for the first time. | ZHAO Jin LI YanJun CHENG GuoXiang | 2007 | Chinese Science Bulletin2007，52，13： | 6 |
| 15 | A Chengjiang-type fossil assemblage from the Hongjingshao Formation(Cambrian Stage 3) at Chenggong, Kunming, Yunnan显示文摘A new Chengjiang-type fossil assemblage is reported herein from the lower part of the Hongjingshao Formation at Xiazhuang village of Chenggong,Kunming,Yunnan.The fossil assemblage,named as Xiazhuang fossil assemblage,yields predominantly soft-bodied fossils,including arthropods,brachiopods,priapulids,lobopods and some problematic taxa,with arthropods being the most dominant group.Preservation and composition of the fossil assemblage are very similar to the typical Chengjiang biota,which is preserved in the middle Yu’anshan Formation in the large area of eastern Yunnan.The associated trilobites demonstrate that the soft-bodied fossil assemblage belongs to the late Qiongzhusian in age(Stage 3,Cambrian),suggesting that the Hongjingshao Formation is probably a diachronous lithostratigraphic unit ranging from the upper Qiongzhusian to the lower Canglangpuan stages in eastern Yunnan.The fossil assemblage from the Xiazhuang area fills up the missing link between the typical older Chengjiang biota and the younger Malong and Guanshan biotas,making eastern Yunnan a unique area in the world to reveal the early evolutionary history of animals and palaeocommunity dynamics during the‘‘Cambrian explosion’’. | Han Zeng Fangchen Zhao Zongjun Yin Guoxiang Li Maoyan Zhu | 2014 | Chinese Science Bulletin2014，59，25： | 6 |
| 16 | Hydrodynamic Links between Shallow and Deep Mineralization Systems and Implications for Deep Mineral Exploration显示文摘Deep mineral exploration is increasingly important for finding new mineral resources but there are many uncertainties.Understanding the factors controlling the localization of mineralization at depth can reduce the risk in deep mineral exploration.One of the relatively poorly constrained but important factors is the hydrodynamics of mineralization.This paper reviews the principles of hydrodynamics of mineralization,especially the nature of relationships between mineralization and structures,and their applications to various types of mineralization systems in the context of hydrodynamic linkage between shallow and deep parts of the systems.Three categories of mineralization systems were examined,i.e.,magmatic-hydrothermal systems,structurally controlled hydrothermal systems with uncertain fluid sources,and hydrothermal systems associated with sedimentary basins.The implications for deep mineral exploration,including potentials for new mineral resources at depth,favorable locations for mineralization,as well as uncertainties,are discussed. | CHI Guoxiang XU Deru XUE Chunji LI Zenghua Patrick LEDRU DENG Teng WANG Yumeng SONG Hao | 2022 | Acta Geologica Sinica(English Edition)2022，96，1： | 5 |
| 17 | Geochemical Characteristics and Sources of Ore-forming Fluids of the Mayuan Pb-Zn Deposit,Nanzheng,Shaanxi,China显示文摘The Mayuan stratabound Pb-Zn deposit in Nanzheng,Shaanxi Province,is located in the northern margin of the Yangtze Plate,in the southern margin of the Beiba Arch.The orebodies are stratiform and hosted in breciated dolostone of the Sinian Dengying Formation.The ore minerals are primarily sphalerite and galena,and the gangue minerals comprise of dolomite,quartz,barite,calcite and solid bitumen.Fluid inclusions from ore-stage quartz and calcite have homogenization tempreatures from 98 to 337℃ and salinities from 7.7 wt%to 22.2 wt%(NaCl equiv.).The vapor phase of the inclusions is mainly composed of CH_4 with minor CO_2 and H_2S.The δD_(fluid) values of fluid inclusions in quartz and calcite display a range from-68‰ to-113‰(SMOW),and the δ^(18)O_(fluid)values calculated from δ^(18)O_(quartz) and δ^(18)O_(calcite) values range from 4.5‰ to 16.7‰(SMOW).These data suggest that the ore-forming fluids may have been derived from evaporitic sea water that had reacted with organic matter.The δ^(13)C_(CH4) values of CH_4 in fluid inclusions range from-37.2‰ to-21.0‰(PDB),suggesting that the CH_4 in the ore-forming fluids was mainly derived from organic matter.This,together with the abundance of solid bitumen in the ores,suggest that organic matter played an important role in mineralization,and that the thermochemical sulfate reduction(TSR) was the main mechanism of sulfide precipitation.The Mayuan Pb-Zn deposit is a carbonate-hosted epigenetic deposit that may be classified as a Mississippi Valley type(MVT) deposit. | LIU Shuwen LI Ronxi CHI Guoxiang ZENG Rong LIU Lingfang SHI Shun | 2015 | Acta Geologica Sinica(English Edition)2015，89，3： | 5 |
| 18 | Detecting land subsidence near metro lines in the Baoshan district of Shanghai with multi-temporal interferometric synthetic aperture radar显示文摘Land subsidence is a major factor that affects metro line(ML) stability. In this study, an improved multitemporal interferometric synthetic aperture radar(InSAR)(MTI) method to detect land subsidence near MLs is presented. In particular, our multi-temporal InSAR method provides surface subsidence measurements with high observation density. The MTI method tracks both point-like targets and distributed targets with temporal radar backscattering steadiness. First, subsidence rates at the point targets with low-amplitude dispersion index(ADI) values are extracted by applying a least-squared estimator on an optimized freely connected network. Second, to reduce error propagation, the pixels with high-ADI values are classified into several groups according to ADI intervals and processed using a Pearson correlation coefficient and hierarchical analysis strategy to obtain the distributed targets. Then,nonlinear subsidence components at all point-like and distributed targets are estimated using phase unwrapping and spatiotemporal filtering on the phase residuals. The proposed MTI method was applied to detect land subsidence near MLs of No. 1 and 3 in the Baoshan district of Shanghai using 18 TerraSAR-X images acquired between April 21,2008 and October 30, 2010. The results show that the mean subsidence rates of the stations distributed along the two MLs are-12.9 and-14.0 mm/year. Furthermore, three subsidence funnels near the MLs are discovered through the hierarchical analysis. The testing results demonstrate the satisfactory capacity of the proposed MTI method in providing detailed subsidence information near MLs. | Tao Li Guoxiang Liu Hui Lin Rui Zhang Hongguo Jia Bing Yu | 2014 | Journal of Modern Transportation2014，22，3： | 4 |
| 19 | Neuritin promotes angiogenesis through inhibition of DLL4/Notch signaling pathway显示文摘Neuritin is a member of the neurotrophic factor family,which plays an important role in the promotion and development of the nervous system.Neuritin is also involved in angiogenesis.Neuritin was recently found to be a negative regulatory factor of the Notch 1 signaling pathway.Notch signaling pathway is known as a regulatory pathway of angiogenesis.Thus,neuritin may play a role in angiogenesis through the Notch signaling pathway.In the present study,we investigated the expressions of neuritin and Notch signaling pathway factors in the pulmonary vascular tissue.The results showed that neuritin expression was increased in the paraneoplastic vascular tissue and decreased in the lung cancer vascular tissue.The neuritin expression was increased with the increase of vascular tissue density,and a negative correlation between neuritin expression and delta-like ligand 4(DLL4)was identified in vascular tissues of lung cancer.Overexpression of neuritin in human umbilical vein endothelial cells(HUVECs)inhibited the expressions of Notch signaling pathway-associated factors,including DLL4,NICD,and Hes-1,and promoted the migration and tubular formation of HUVECs.In conclusion,our results indicated that neuritin is involved in angiogenesis and may play a role in angiogenesis through the Notch signaling pathway.This study provides a theoretical basis for clinical anti-angiogenesis therapy. | Li Yang Xuhui Wang Jiawei Sun Chunyan Liu Guoxiang Li Jingling Zhu Jin Huang | 2021 | Acta Biochimica et Biophysica Sinica2021，53，6： | 4 |
| 20 | Image segmentation algorithm for greenhouse cucumber canopy under various natural lighting conditions显示文摘In this study,machine vision technology was used to capture images of greenhouse cucumber canopy,and image segmentation was implemented under various natural lighting conditions.The images were enhanced by multi-scale retinex with color restore(MSRCR),and the MSRCR images were segmented by four algorithms:normalized difference index(NDI),excess green(ExG),modified excess green(MExG),and modified excess green minus excess red(MExG-ExR).The results indicated that compared with the original images,under various lighting conditions,the average evaluation indexes of brightness,information entropy,average gradient and mean gray value of the MSRCR images were increased by 38.71%,8.04%,4.54%,and 37.81%,respectively,and only the contrast degree decreased by 12.13%.The MExG-ExR segmentation algorithm was used to segment the MSRCR images(fifty images under various lighting conditions in the test and it performed best among the four segmentation algorithms,average overlap ratios and recognition rates of were 99.28%and 98.91%,respectively,while 38.39%and 37.95%respectively for original image.These results indicated that the MExG-ExR segmentation algorithm applied to a MSRCR canopy image produced the most stable results among the four algorithms.By using the MSRCR image enhancement algorithm,the interference of lighting on greenhouse cucumber canopy images was reduced and the foundation for achieving accurate segmentation of a canopy region was laid,which is of great significance for greenhouse cucumber phenotypic parameter measurements. | Sun Guoxiang Li Yongbo Wang Xiaochan Hu Guyue Wang Xuan Zhang Yu | 2016 | International Journal of Agricultural and Biological Engineering2016，9，3： | 4 |
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