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1Tectonics of South China Continent and its implications显示文摘This paper aims at exploring the tectonic characteristics of the South China Continent(SCC)and extracting the universal tectonic rules from these characteristics,to help enrich the plate tectonic theory and better understand the continental dynamic system.For this purpose,here we conduct a multi-disciplinary investigation and combine it with the previous studies to reassess the tectonics and evolution of SCC and propose that the tectonic framework of the continent comprises two blocks,three types of tectonic units,four deformation systems,and four evolutionary stages with distinctive mechanism and tectonic characteristics since the Neoproterozoic.The four evolutionary stages are:(1)The amalgamation and break-up of the Neoproterozoic plates,typically the intracontinental rifting.(2)The early Paleozoic and Mesozoic intracontinental orogeny confined by plate tectonics,forming two composite tectonic domains.(3)The parallel operation of the Yangtze cratonization and intracontinental orogeny,and multi-phase reactivation of the Yangtze craton.(4)The association and differentiation evolution of plate tectonics and intracontinental tectonics,and the dynamic characteristics under the Meso-Cenozoic modern global plate tectonic regime.ZHANG GuoWei GUO AnLin WANG YueJun LI SanZhong DONG YunPeng LIU ShaoFeng HE DengFa CHENG ShunYou LU RuKui YAO AnPing 2013Science China Earth Sciences2013,56,11:88
2Human colorectal cancer-specific CCAT1-L IncRNA regulates long-range chromatin interactions at the MYC locus显示文摘人的 8q24 基因沙漠包含多重 enhancers 形式织物特定的远程的染色质与 MYC oncogene 循环,但是染色质在 MYC 地点循环怎么被调整,仍然保持糟糕理解。这里,我们表明那长 noncoding RNA (lncRNA ) , CCAT1-L,从一个地点在人的 colorectal 癌症明确地被抄录 MYC 在上游的 515 kb。这 lncRNA 在 MYC transcriptional 规定起一个作用并且支持远程的染色质循环。重要地, CCAT1-L 地点位于强壮的超级提高以内并且离 MYC 空间地靠近。CCAT1-L 击倒在 MYC 倡导者和它的 enhancers 之间的减少的远程的相互作用。另外, CCAT1-L 与 CTCF 交往并且在这些环区域调制染色质符合构造。这些结果揭示一个重要角色一以前在在 MYC 地点的基因规定的 unannotated lncRNA。Jian-Feng Xiang Qing-Fei Yin Tian Chen Yang Zhang Xiao-Ou Zhang Zheng Wu Shaofeng Zhang Hai-Bin Wang Junhui Ge Xutiua Lu Li Yang Ling-Ling Chen 2014Cell Research2014,24,5:67
3Process of Rifting and Collision along Plate Margins of the Qinling Orogenic Belt and Its Geodynamics显示文摘The Qinling erogenic belt underwent complicated processes of rifting and collision, as shown by the coexistence of (1) ocean extension and plate margin rifting and (2) subduction of the frontal oceanic crust and extension of the rear plate margin. These resulted in a basin-mountain framework characterized by the coexistence of plates separated by the ocean basin and continental blocks demarcated by the rifting sea trough in the marginal region and the coexistence of subduction orogeny and ocean extension. Generally speaking, the plate marginal area between the North China plate and Yangtze plate continually rifted from north to south and the rifted micro-plates continually accreted northwards. This especial orogenic process was probably controlled by two events of deep mantle geody-namic adjustment and mantle plume activities, which occurred in the Shangdan suture belt and Mianlue suture belt from north to south respectively.LIU Shaofeng ZHANG Guowei 1999Acta Geologica Sinica(English Edition)1999,73,3:20
4Fractionation of heavy metals in shallow marine sediments from Jinzhou Bay,China显示文摘This work investigated the distribution and speciation of Cd, Cu, Pb, Fe and Mn in the shallow sediments of Jinzhou Bay, Northeast China, which has been heavily contaminated by nonferrous smelting activities. The concentrations of Cd, Cu and Pb in sediments were found to be 100, 13 and 7 times, respectively, being higher than the national guideline (GB 18668-2002). Sequential extraction test showed that 39%-61% of Cd were exchangeable fractions, indicating that Cd in the sediments posed a high risk to local environments. While Cu and Pb were at moderate risk levels. According to the relationships between percentage of metal speciation and total metal concentration, it was concluded that the distributions of Cd, Cu and Pb in some geochemical fractions were dynamic in the process of pollutants migration and the stability of metals in sediments of Jinzhou Bay decreased in the order of Pb > Cu > Cd.Shaofeng Wang, Yongfeng Jia, Shuying Wang, Xin Wang, He Wang, Zhixi Zhao, Bingzhu LiuKey Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. 2010Journal of Environmental Sciences2010,22,1:20
5Cenozoic basin development and its indication of plateau growth in the Xunhua-Guide district显示文摘The Xunhua, Guide and Tongren Basins are linked with the Laji Mountain and the northern West Qinling thrust belts in the Xunhua-Guide district. Basin depositional stratigraphy consists of the Oligocene Xining Group, the uppermost Oligocene-Pliocene Guide Group and the Lower Pleistocene. They are divided into three basin phases by unconformities. Basin phase 1 is composed of the Xining Group, and Basin phase 2 of the Zharang, Xiadongshan, Herjia and Ganjia Conglomerate Formations in the Guide Group, and Basin phase 3 of the Gonghe Formation and the Lower Pleistocene. Three basin phases all develop lacustrine deposits at their lower parts, and alluvial-braided channel plain depositional systems at upper parts, which constitute a coarsening-upward and progradational sequence. Basin deposition, paleocurrent and provenance analyses represent that large lacustrine basin across the Laji Mountain was developed and sourced from the West Qinling thrust belt during the stage of the Xining Group (Basin phase 1), and point-dispersed alluvial fan-braided channel plain deposition systems were developed beside the thrust and uplifted Laji Mountain and sourced from it, as thrusting migrated northwards during the stage of the Guide Group (Basin phase 2). Evolution of basin-mountain system in the study area significantly indicates the growth process of the distal Tibetan Plateau. The result shows that the Tibetan Plateau expanded to the northern West-Qinling at Oligocene (29―21.4 Ma) by means of northward folded-and-thrust thickening and uplifting and frontal foreland basin filling, and across the study area to North Qilian and Liupan Mountain at the Miocene-Pliocene (20.8―2.6 Ma) by means of two-sided basement-involved-thrust thickening and uplifting and broken foreland basin filling, and the distant end of Tibetan Plateau behaved as regional erosion and intermontane basin aggradational filling during the Pliocene and early Pleistocene (2.6―1.7 Ma).LIU ShaoFeng ZHANG GuoWei P.L.HELLER 2007Science China Earth Sciences2007,50,z2:17
6COVID-19 Outbreak Caused by Contaminated Packaging of Imported Cold-Chain Products—Liaoning Province,China,July 2020显示文摘Summary What is known about this topic?Few major outbreaks of coronavirus disease 2019(COVID-19)have occurred in China after major nonpharmaceutical interventions and vaccines have been deployed and implemented.However,sporadic outbreaks that had high possibility to be linked to cold chain products were reported in several cities of China..What is added by this report?In July 2020,a COVID-19 outbreak occurred in Dalian,China.The investigations of this outbreak strongly suggested that the infection source was from COVID-19 virus-contaminated packaging of frozen seafood during inbound unloading personnel contact.What are the implications for public health practice?Virus contaminated paper surfaces could maintain infectivity for at least 17–24 days at-25℃.Exposure to COVID-19 virus-contaminated surfaces is a potential route for introducing the virus to a susceptible population.Countries with no domestic transmission of COVID-19 should consider introducing prevention strategies for both inbound travellers and imported goods.Several measures to prevent the introduction of the virus via cold-chain goods can be implemented.Huilai Ma1 Jianqun Zhang Ji Wang Ying Qin Cao Chen Yang Song Liang Wang Jun Meng Lingling Mao Fengqin Li Ning Li Jian Cai Yong Zhang Dayan Wang Yunting Xia Hong Wang Shaofeng Jiang Xiang Zhao Peihua Niu Wenjie Tan Tao Ma Yecheng Yao Naiying Mao Zhen Zhu Tianjiao Ji Qian Yang Baoying Huang Li Zhao Jianxing Yu Li Bai Shuangli Zhu Dongyan Wang Yan Zhang Yingwei Sun Mingchun Luan Yanhai Wang Haibo Sun Shihong Yang Zhijian Bo Xiang Ren Zhongjie Li George Fu Gao Wei Yao Wenqing Yao Zijian Feng Wenbo Xu 2021China CDC weekly2021,3,21:16
7Typical basin-fill sequences and basin migration in Yanshan, North China ——Response to Mesozoic tectonic transition显示文摘Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. China University of Geosciences, Beijing 100083, ChinaCorrespondence should be addressed to Li Zhong (email: lizhongd@mail.igcas.ac.cn) 2004Science China Earth Sciences2004,47,2:15
8A local geopotential model for implementation of underwater passive navigation显示文摘A main aspect of underwater passive navigation is how to identify the vehicle location on an existing gravity map, and several match-ing algorithms as ICCP and SITAN are the most prevalent methods that many scholars are using.In this paper, a novel algorithm that is difierent from matching algorithms for passive navigation is developed.The algorithm implements underwater passive navigation by directly estimating the inertial errors through Kalman filter algorithm, and the key part of this implementation is a Fourier series-based local geopotential model.Firstly, the principle of local geopotential model based on Fourier series is introduced in this paper, thus the discrete gravity anomalies data can be expressed analytically with respect to geographic coordinates to establish the observation equation required in the application of Kalman filter.Whereafter, the indicated gravity anomalies can be gotten by substituting the inertial posi-tions to existing gravity anomalies map.Finally, the classical extended Kalman filter is introduced with the difierences between measured gravity and indicated gravity used as observations to optimally estimate the errors of the inertial navigation system (INS).This naviga-tion algorithm is tested on simulated data with encouraging results.Although this algorithm is developed for underwater navigation using gravity data, it is equally applicable to other domains, for example vehicle navigation on magnetic or terrain data.Zhigang Wang Shaofeng Bian 2008Progress in Natural Science:Materials International2008,18,9:14
9Mushroom Poisoning Outbreaks-China,2020显示文摘What is already known about this topic?Acute liver failure,rhabdomyolysis,acute renal failure,and hemolysis caused by poisonous mushrooms are the most important mushroom poisoning threats to the Chinese population.The most notorious lethal mushrooms are the species from genera Amanita,Lepiota,and Galerina that cause acute liver failure,and Russula subnigricans that leads to rhabdomyolysis.What is added by this report?In 2020,the total number of investigations reached 676,involving an estimated 102 species of poisonous mushrooms,24 of which were newly recorded in China.Gyromitra venenata was newly discovered in incidents in Yunnan and Guizhou provinces and were the first reported poisonings due to gyromitrins in China since 2000.The rare poisoning Shiitake mushroom dermatitis was recorded in China.Hemolysis poisoning caused by Paxillus involutus was recorded for the second time since the beginning of the new century,resulting in one death in Inner Mongolia Autonomous Region.What are the implications for public health practice?Promoting knowledge about safe consumption of mushrooms is essential to reduce mushroom poisonings.It is not wise to collect and eat wild mushrooms.For southwestern provinces such as Yunnan,especially,caution must be exercised with unfamiliar mushroom species.Haijiao Li Hongshun Zhang Yizhe Zhang Jing Zhou Yu Yin Qian He Shaofeng Jiang Peibin Ma Yutao Zhang Ke Wen Yuan Yuan Nan Lang Bowen Cheng Junjia Lu Chengye Sun 2021China CDC weekly2021,3,3:13
10Long Distance Transmission of SARS-CoV-2 from Contaminated Cold Chain Products to Humans——Qingdao City,Shandong Province,China,September 2020显示文摘Summary What is already known about this topic?Though coronavirus disease 2019(COVID-19)has largely been controlled in China,several outbreaks of COVID-19 have occurred from importation of cases or of suspected virus-contaminated products.Though several outbreaks have been traced to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)isolated on the outer packaging of cold chain products,live virus has not been obtained.Huilai Ma Zhaoguo Wang Xiang Zhao Jun Han Yong Zhang Hong Wang Cao Chen Ji Wang Fachun Jiang Jie Lei Jingdong Song Shaofeng Jiang Shuangli Zhu Huihui Liu Dongyan Wang Yao Meng Naiying Mao Yanhai Wang Zhen Zhu Zhixiao Chen Bingling Wang Qinqin Song Haijun Du Qun Yuan Dong Xia Zhiqiang Xia Peipei Liu Yuchao Wu Zijian Feng Ruqin Gao George F.Gao Wenbo Xu 2021China CDC weekly2021,3,30:13
11Mesozoic basin development and its indication of collisional orogeny in the Dabie orogen显示文摘The Dabie orogen underwent deep continental subduction, rapid exhumation, and the huge amount of erosion during the Mesozoic. Its tectonic evolution, especially how its evolution was recorded by sedimentary basins at the flanks of the Dabie orogen is one of the most important issues of the world's attention. These years, newly studies of basin sedimentology, combined with structural geology, have shown a fundamental progress. The overall distribution of different basin types in the orogen indicates that shortening and thrusting at the margins of the orogen from the Late Triassic to the Early Cretaceous controlled the foreland basins, and extension, doming and rifting were initiated in the core of the orogen from the Jurassic to the Early Cretaceous and were expanded to the whole orogen after the Late Cretaceous. Therefore, The Dabie orogen records gradual transition from overall shortening and thrusting to dominantly extension and rift basin formation expanded from its core to its margins, although these shortening and extension overlapped in time from the Jurassic through Early Cretaceous at crustal levels. The unroofing ages of the ultra-high pressure (UHP) metamorphic rocks in the Dabie orogen change from Early Jurassic to Late Jurassic westward. The depth of exhumation increases eastwards. The sediment sources for the Hefei basin are mostly composed of the deeply exhumed, axial Dabie metamorphic complex, and the sediment sources for the Middle Yangtze basin are mostly from cover strata in the southern orogen and related strata with subjacent (i.e. subsequently overthrusted) Mianlue suture belt. Geodynamic analysis represents that continental collision between the North China Block and the South China Block along the Shangdan and Mianlue sutures, subsequently northwestward progradation of the Jiangnan fold and thrust belt, and the underthrusting of the North China Block along the Northern Boundary Fault of Qinling Range led to crustal thickening, gravitational spreading and balanced rebound of the resultant thick crustal welt, and multi-episodic exhumation of the HP/UHP metamorphic rocks. The future studies by the methods of tracing the Dabie orogeny through deposition in the marginal basins should focus on eastward extension of the Mianlue suture, thrust and overlap of the Dabie HP/UHP metamorphic block on different lithotectonic zones and basins along the northern South China Block, the structural framework of the source area of the basins in the syn-depositional stage, the basin lateral extension, huge amount of erosion and sediment transportation from the Dabie blanket and basement rocks, and recovery of subducted and re- moved structural units within the Dabie orogen, etc.LIU ShaoFeng ZHANG GuoWei 2013Chinese Science Bulletin2013,58,8:12
12The Late Triassic Sequence-Stratigraphic Framework of the Upper Yangtze Region,South China显示文摘In the transitional period between the Middle and the Late Triassic, the Indochina orogeny caused two tectonic events in South China:(1) the formation and uplift of the Qinling-Dabie orogenic belt along the northern margin of the South China Plate, due to its collision with the North China Plate; and 2) the development of a 1300-km-wide intra-continental orogen in the southeastern part of the South China Plate, which led to a northwestward movement of the foreland thrust-fold zone. These tectonic events resulted in the ending of the Yangtze Platform, and were a stable paleogeographic factor from the Eidacaran to the end of the Middle Triassic. This platform was characterized by the widespread development of shallow-water carbonates. After the end of the Yangtze Platform, the upper Yangtze foreland basin(or Sichuan foreland basin) was formed during the Late Triassic and became a accumulation site of fluvial deposits that are composed of related strata of the Xujiahe Formation. In western Sichuan Province, the Xujiahe Formation overlies the Maantang Formation shallow-water carbonate rocks of the Xiaotangzi Formation siliciclastic rocks(from shelf shales to littoral facies). The sequence-stratigraphic framework of the Upper Triassic in the upper Yangtze foreland basin indicates a particular alluvial architecture, characterized by sequences composed of(1) successions of low-energy fluvial deposits of high-accommodation phases, including coal seams, and(2) high-energy fluvial deposits of low-accommodation phases, including amalgamated river-channel sandstones. The spatial distribution of these fluvial deposits belonging to the Xujiahe Formation and its relative strata is characterized by gradual thinning-out, overlapping, and pinching-out toward both the east and south. This sedimentary record therefore expresses a particular sequence-stratigraphic succession of fluvial deposits within the filling succession of the foreland basin. The sequence-stratigraphic framework for the Upper Triassic in the Upper Yangtze region provides a record of the end of the Yangtze Platform and the formation of the upper Yangtze foreland basin.MEI Mingxiang LIU Shaofeng 2017Acta Geologica Sinica(English Edition)2017,91,1:11
13Inactivation of Cryptosporidium by ozone and cell ultrastructures显示文摘The fluorescence staining method and scanning electron microscopy (SEM) were used to study the effect of ozone (O3) inactivating Cryptosporidium in water and cell ultrastructures variation to shed light on the mechanism of inactivation preliminarily.Results indicated that O3 had a stronger inactivating capability.When the concentration of O3 was above 3.0 mg/L and the contact time was up to 7 min,a significant inactivating effect could be achieved.The turbidity on inactivation effects was also found to be statistically significant in artificial water.With increases in turbidity,the inactivating effect decreased.Inactivation rate improved with a temperature increase from 5 to 25°C,but decreased beyond this.The inactivating capability of O3 was found to be stronger under acidic than that under alkalic conditions.When the concentration of organic matter in the reaction system was increased,the competition between Cryptosporidium and organics with O3 probably took place,thereby reducing the inactivation rate.In addition,the cellular morphology of Cryptosporidium varied with different contact times.At zero contact time,cells were rotundity and sphericity,at 60 sec they became folded,underwent emboly,and burst at 480 sec,the cell membrane of Cryptosporidium shrinked and collapsed completely.Zhilin Ran Shaofeng Li Junli Huang Yixing Yuan Chongwei Cui Craig Denver Williams 2010Journal of Environmental Sciences2010,22,12:11
14Mushroom Poisoning Outbreaks--China,2019显示文摘What is already known about this topic?Mushroom poisoning is becoming one of the most serious food safety issues in China,which is responsible for nearly a half of all oral poisoning deaths.What is added by this report?In China,many mushrooms were previously“recorded”as poisonous.In this study,about 70 species obtained from mushroom poisoning incidents including several new records were confirmed accurately by morphological and molecular evidence in 2019,and spatial and temporal distribution characters of 13 lethal mushrooms were summarized systematically.What are the implications for public health practice?Precise and timely species identification is of pivotal importance in mushroom incidents.More efforts and cooperation are continued to be needed urgently for the governments,CDC staff,doctors and mycologists in future.Haijiao Li Hongshun Zhang Yizhe Zhang Kaiping Zhang Jing Zhou Yu Yin Shaofeng Jiang Peibin Ma Qian He Yutao Zhang Ke Wen Yuan Yuan Nan Lang Junjia Lu Chengye Sun 2020China CDC weekly2020,2,2:11
15The long-term stability of calcium arsenates:Implications for phase transformation and arsenic mobilization显示文摘It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.Danni Zhang Shaofeng Wang Ying Wang Mario A.Gomez Yongfeng Jia 2019Journal of Environmental Sciences2019,31,10:10
16In situ stable isotopic constraints on dolomitizing fluids for the hydrothermally-originated saddle dolomites at Keping, Tarim Basin显示文摘Detailed characterization of diagenetic fluid behaviour and evolution is commonly hindered by shortage of appropriate and economic methods to carry out in situ analysis in the tiny diagenetic mineral crystals. Using micromill sampling method, this study presents in situ stable isotopic data for the growth zones of saddle dolomite crystals in the hydrothermally-altered dolostones of Upper Cambrian (Furongian) at Keping, Tarim Basin, NW China. These data show minor and large variations in δ13C ( 0.7‰ to 1.5‰ VPDB) and δ18O ( 8.3‰ to 13.8‰ VPDB), respectively, from the cores to outer rims of the dolomite crystals and suggest that saddle dolomites precipitated from dolomitizing fluids with similar carbon sources but oscillatory temperatures during different formation stages. This scenario is confirmed by microthermometry of fluid inclusions within the growth zones of dolomite crystals. This study indicates that in situ isotope analysis could provide more detailed information related to the source and pathway of dolomitizing fluids, facilitating better characterization of dolomitizing fluids and processes.DONG ShaoFeng CHEN DaiZhao QING HaiRuo JIANG MaoSheng ZHOU XiQiang 2013Chinese Science Bulletin2013,58,23:9
17Isotope chronological trace of granite gravel in Hefei Basin显示文摘The discovery of granite gravel in Hefei Jurassic backland basin, which came from the Dabie Shan or North Huaiyang, has a great significance for probing into uplift and exhumation of the Dabie orogenic belt. Litho-chemical and isotope chronological analyses on the granite gravel in the Sanjianpu Formation and the Fenghuangtai Formation in Jinzhai County prove that post-orogenic granite was developed in the major provenance of the Hefei Basin; that is, Dabie Shan or North Huaiyang. Discordant lower intersection point age of zircon U-Pb of granite gravel is about 214 Ma, and 40Ar/39Ar age of muscovite about 196 Ma, K-Ar age of K-spar about 181 Ma. The former is the diagenetic age of the sample, and the latter two represent the sealed ages of muscovite and K-spar respectively. The age of sedimentary rocks in which a lot of granite gravels appear in the sedimentary section may represent the newest age of the exhumation of the granite body, so we assume that the age is 166 Ma. Therefore, we calculated theLIU Shaofeng ZHANG Guowei ZHANG Zongqing SU Shangguo 2001Chinese Science Bulletin2001,46,20:9
18The Pengguan tectonic dome of Longmen Mountains, Sichuan Province:Mesozoic denudation of a Neoproterozoic magmatic arc-basin system显示文摘Neoproterozoic igneous and metamorphic complexes occur as tectonic domes in the Longmen Mountains of the western margin of the Yangtze Block, and are important in reconstructing the Rodinian supercontinent and constraining the timing and mechanism of tectonic denudational processes. The Pengguan dome consists of granitic intrusions and metamorphic rocks of the Huangshuihe Group and is tectonically overlain by ductilly deformed Sinian to Paleozoic strata. The plutonic intrusions consist of granites with abundant amphibolite enclaves. New LA-ICP-MS zircon U-Pb dating yielded an emplacement age of 809±3 Ma and a protolith age of 844±6 Ma for the granite. The granitic rocks have geochemical signatures typical of A-type granites, indicating their formation under an extensional environment, by melting of newly formed tonalite-trondhjemite-granodiorite (TTG) rocks. A detachment fault, characterized by variable ductile shear deformation of S-C fabric and ESE-ward kinematics, separates the Pengguan dome from the Sinian-Paleozoic cover. 40Ar/39Ar dating of muscovite from the mylonite in the detachment fault of the dome demonstrates that ductile deformation occurred at ~160 Ma. This study indicates the existence of a Neoproterozoic magmatic arc-basin system, which was denudated by a Jurassic middle crustal ductile channel flow along the Longmenshan thrust belt.YAN DanPing ZHOU MeiFu WEI GuoQing GAO JianFeng LIU ShaoFeng XU Ping SHI XiaoYing 2008Science China Earth Sciences2008,51,11:9
19Experimental investigation on micro-dynamic behavior of gas explosion suppression with SiO_2 fine powders显示文摘To study the effect of inert dust on gas explosion suppression mechanism,SiO_2 fine powders were sprayed to suppress premixed CH_4-Air gas explosion in a 20 L spherical experimental system.In the experiment,high speed schlieren image system was adopted to record explosion flame propagation behaviors,meanwhile,pressure transducers and ion current probes were used to clearly record the explosion flame dynamic characteristics.The experimental results show that the SiO_2 fine powders suppressed evidently the...Xianfeng Chen,~(1,2,a)) Yin Zhang,~1 Qingming Zhang,~2 Shaofeng Ren,~1 and Jianxing Wu~1 1)School of Natural Resources and Environmental Engineering,Wuhan University of Technology, Wuhan 430070,China 2)State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology, Beijing 100081,China 2011Theoretical & Applied Mechanics Letters2011,1,3:8
20Analyzing and modeling the coverage of vegetation in the Qaidam Basin of China: The role of spatial autocorrelation显示文摘在植被和环境因素之间的关系总是是在生态学的一个主要话题,但是揭示植被也是一个重要方法对的动态反应和气候上的效果改变的反馈。为特殊地理地点和 Qaidam 盆的气候的特征,与支持传统并且遥感数据,在这份报纸,一个植被范围模型被建立。由五个环境因素的植被范围的量的预言开始通过多重逐步的回归(MSR ) 被认识到模型。然而,在这五个环境因素之中有重要 multicollinearity,它减少 MSR 模型的表演。然后通过 Moran 的介绍索引,反映植被分发,仅仅平均年度降雨的二个变量和本地 Moran 索引的空间自相关的指示物在植被范围模型的最后的建立被使用。结果证明在植被的分发有重要空间自相关。在植被范围模型的建立的空间自相关的角色让改进不仅从 0.608 ~ 0.656 的模型试穿 R2,而且在独立人士之中移开 multicollinearity。ZHU Wenbin JIA Shaofeng LU Aifeng YAN Tingting 2012Journal of Geographical Sciences2012,22,2:8
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