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| 1 | Tectonics 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 | 2013 | Science China Earth Sciences2013，56，11： | 88 |
| 2 | Process 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 | 1999 | Acta Geologica Sinica(English Edition)1999，73，3： | 20 |
| 3 | Cenozoic 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 | 2007 | Science China Earth Sciences2007，50，z2： | 17 |
| 4 | Typical 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) | 2004 | Science China Earth Sciences2004，47，2： | 15 |
| 5 | Long 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 | 2021 | China CDC weekly2021，3，30： | 13 |
| 6 | Mesozoic 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 | 2013 | Chinese Science Bulletin2013，58，8： | 12 |
| 7 | The 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 | 2017 | Acta Geologica Sinica(English Edition)2017，91，1： | 11 |
| 8 | Isotope 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 the | LIU Shaofeng ZHANG Guowei ZHANG Zongqing SU Shangguo | 2001 | Chinese Science Bulletin2001，46，20： | 9 |
| 9 | The 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 | 2008 | Science China Earth Sciences2008，51，11： | 9 |
| 10 | 中国大陆麻醉住院医师毕业后教育的探讨显示文摘经过近几年在全国部分省市试点后,2015年教育部和卫计委正式通知在全国范围内改变医学教育的现有模式,新的规范化培养(简称规培)已经逐步开展并日渐规范。各专科住院医师规范化培训的目的是培养具有现代医学素质的专职人员,能够胜任现代医学的临床要求。同时对住院医师进行评估和考核已经日趋重要,同样需要通过规范化的方式进行。现将美国麻醉住院医师培训考核模式与国内麻醉住院医师考核方式进行比较。 | 王振猛 Chuanyao Tong Lingzhong Meng Jianzhong Sun Shaofeng Zhou Zhongcong Xie Hong Liu 张成密 赵晶 俞卫锋 | 2015 | 临床麻醉学杂志2015，31，11： | 7 |
| 11 | Spatiotemporal characteristics of GNSS-derived precipitable water vapor during heavy rainfall events in Guilin,China显示文摘Precipitable Water Vapor(PWV),as an important indicator of atmospheric water vapor,can be derived from Global Navigation Satellite System(GNSS)observations with the advantages of high precision and all-weather capacity.GNSS-derived PWV with a high spatiotemporal resolution has become an important source of observations in mete-orology,particularly for severe weather conditions,for water vapor is not well sampled in the current meteorological observing systems.In this study,an empirical atmospheric weighted mean temperature(Tm)model for Guilin is estab-lished using the radiosonde data from 2012 to 2017.Then,the observations at 11 GNSS stations in Guilin are used to investigate the spatiotemporal features of GNSS-derived PWV under the heavy rainfalls from June to July 2017.The results show that the new Tm model in Guilin has better performance with the mean bias and Root Mean Square(RMS)of−0.51 and 2.12 K,respectively,compared with other widely used models.Moreover,the GNSS PWV estimates are validated with the data at Guilin radiosonde station.Good agreements are found between GNSS-derived PWV and radiosonde-derived PWV with the mean bias and RMS of−0.9 and 3.53 mm,respectively.Finally,an investigation on the spatiotemporal characteristics of GNSS PWV during heavy rainfalls in Guilin is performed.It is shown that variations of PWV retrieved from GNSS have a direct relationship with the in situ rainfall measurements,and the PWV increases sharply before the arrival of a heavy rainfall and decreases to a stable state after the cease of the rainfall.It also reveals the moisture variation in several regions of Guilin during a heavy rainfall,which is significant for the moni-toring of rainfalls and weather forecast. | Liangke Huang Zhixiang Mo Shaofeng Xie Lilong Liu Chuanli Kang Shitai Wang | 2021 | Satellite Navigation2021，2，1： | 6 |
| 12 | Syn-tectonic sedimentation and its linkage to fold-thrusting in the region of Zhangjiakou, North Hebei, China显示文摘The timing of the 'Yanshanian Movement' and the tectonic setting that controlled the Yanshan fold-and-thrust belt during Jurassic time in China are still matters of controversy. Sediments that filled the intramontane basins in the Yanshan belt perfectly record the history of 'Yanshanian Movement' and the tectonic background of these basins. Recognizing syn-tectonic sedimentation, clarifying its relationship with structures, and accurately defining strata ages to build up a correct chronostratigraphic framework are the key points to further reveal the timing and kinematics of tectonic deformation in the Yanshan belt from the Jurassic to the Early Cretaceous. This paper applies both tectonic and sedimentary methods on the fold-and-thrust belt and intramontane basins in the Zhangjiakou area, which is located at the intersection between the western Yanshan and northern Taihangshan. Our work suggests that the pre-defined 'Jurassic strata' should be re-dated and sub-divided into three strata units: a Late Triassic to Early Jurassic unit, a Middle Jurassic unit, and a Late Jurassic to early Early Cretaceous unit. Under the control of growth fold-and-thrust structures, five types of growth strata developed in different growth structures: fold-belt foredeep type,thrust-belt foredeep type, fault-propagation fold-thrust structure type, fault-bend fold-thrust structure type, and fault-bend foldthrust plus fault-propagation fold composite type. The reconstructed 'source-to-sink' systems of Late Triassic to Early Jurassic,Middle Jurassic and Late Jurassic to early Early Cretaceous times, which are composed of a fold-and-thrust belt and flexure basins, imply that the 'Yanshanian Movement' in our study area started in the Middle Jurassic. During Middle Jurassic to early Early Cretaceous times, there have been at least three stages of fold-thrust events that developed 'Laramide-type' basementinvolved fold-thrust structures and small-scale intramontane broken 'axial basins'. The westward migration of a 'pair' of basement-involved fold-thrust belt and flexure basins might have been controlled by flat subduction of the western Paleo-Pacific slab from the Jurassic to the Early Cretaceous. | Shaofeng LIU Chengfa LIN Xiaobo LIU Qitian ZHUANG | 2018 | Science China Earth Sciences2018，61，6： | 6 |
| 13 | New research trends on high-precision time transfer technology显示文摘High-precision time transfer plays an important role in the areas of fundamental research and applications. Accompanying w ith the remarkable improvements in the ability of generating and measuring high-accuracy time-frequency signal,seeking for new time-transfer techniques betw een distant clocks w ith much further improved accuracy attracts attentions w orld-w idely. The time-transfer technique based on optical pulses has the highest precision presently,and the further improvement in the accuracy is heavily dependent on the time-domain properties of the pulse as w ell as the sensitivity of the applied measurement on the exchanged pulse. The application of optical frequency comb in time transfer for a precision up to femtosecond level are currently the focus of much interest,and has recently achieved many breakthroughs. Further investigations show that,utilizing quantum techniques,i.e. quantum measurement technique and quantum optical pulse source,can lead to a new limit on the measured timing information. Furthermore,it can be immune from atmospheric parameters,such as pressure,temperature,humidity and so on.Such quantum improvements on time-transfer have a bright prospect in the future applications requiring extremely high-accuracy timing and ranging. The potential achievements w ill form a technical basis for the future realization of sub-femtosecond time transfer system. | DONG Ruifang QUAN Run'ai HOU Feiyan WANG Shaofeng XIANG Xiao ZHOU Conghua WANG Mengmeng LIU Tao ZHANG Shou'gang | 2015 | Instrumentation2015，2，4： | 5 |
| 14 | Abnormal Metabolic Connectivity in Rats at the Acute Stage of Ischemic Stroke显示文摘Stroke at the acute stage is a major cause of disability in adults, and is associated with dysfunction of brain networks. However, the mechanisms underlying changes in brain connectivity in stroke are far from fully elucidated. In the present study, we investigated brain metabolism and metabolic connectivity in a rat ischemic stroke model of middle cerebral artery occlusion(MCAO)at the acute stage using18 F-fluorodeoxyglucose positron emission tomography. Voxel-wise analysis showed decreased metabolism mainly in the ipsilesional hemisphere, and increased metabolism mainly in the contralesional cerebellum. We used further metabolic connectivity analysis to explore the brain metabolic network in MCAO.Compared to sham controls, rats with MCAO showed most significantly reduced nodal and local efficiency in the ipsilesional striatum. In addition, the MCAO group showed decreased metabolic central connection of the ipsilesional striatum with the ipsilesional cerebellum, ipsilesional hippocampus, and bilateral hypothalamus. Taken together,the present study demonstrated abnormal metabolic connectivity in rats at the acute stage of ischemic stroke, which might provide insight into clinical research. | Shengxiang Liang Xiaofeng Jiang Qingqing Zhang Shaofeng Duan Tianhao Zhang Qi Huang Xi Sun Hua Liu Jie Dong Weilin Liu Jing Tao Shujun Zhao Binbin Nie Lidian Chens Baoci Shan | 2018 | Neuroscience Bulletin2018，34，5： | 5 |
| 15 | A new stationary droplet evaporation model and its validation显示文摘The liquid droplet evaporation character is important for not only combustion chamber design process but also high-accuracy spray combustion simulation. In this paper, the suspended droplets' evaporation character was measured in a quiescent high-temperature environment by micro high-speed camera system. The gasoline and kerosene experimental results are consistent with the reference data. Methanol, common kerosene and aviation kerosene droplet evaporation characteristics, as well as their evaporation rate changing with temperature, were obtained. The evaporation rate experimental data were compared with the prediction result of Ranz-Marshall boiling temperature model(RMB), Ranz-Marshall low-temperature model(RML), drift flux model(DFM), mass analogy model(MAM), and stagnant film model(SFM). The disparity between the experimental data and the model prediction results was mainly caused by the neglect of the natural convection effect, which was never introduced into the droplet evaporation concept. A new droplet evaporation model with consideration of natural convection buoyancy force effect was proposed in this paper. Under the experimental conditions in this paper, the calculation results of the new droplet evaporation model were agreed with the experimental data for kerosene, methanol and other fuels, with less than 20% relative deviations. The relative deviations between the new evaporation model predictions for kerosene and the experimental data from the references were within 10%. | Fang WANG Jie YAO Shaofeng YANG Rui LIU Jie JIN | 2017 | Chinese Journal of Aeronautics2017，30，4： | 5 |
| 16 | Assessment of outcomes of hearing and speech rehabilitation in children with cochlear implantation显示文摘Objectives:This study aimed to assess the effect of hearing and speech rehabilitation in patients with Nurotron■cochlear implants.Design:Ninety-eight paediatric patients with bilateral severe-to-profound sensorineural deafness who received cochlear implantation were divided into three groups according to age:group A(≤3 years),group B(4-7 years),and group C(8-16 years).All patients were followed up for one year for hearing and speech performance after the surgery.The comprehensive Auditory Perception Assessment,MAIS,CAP and SIR hearing and speech assessments and rating materials were used for assessment before the surgery and at 3,6,and 12 months after implant activation.Results:The scores of patients in the open-set speech assessment,Chinese Auditory Perception Assessment,MAIS,CAP and SIR significantly improved after cochlear implantation in all age groups.The younger the age at implantation,the better the results.Moreover,the hearing and speech performance of cochlear implant recipients gradually improved with the extension of rehabilitation time.Conclusions:Nurotron■Venus^TM cochlear implantation can improve the hearing and speech performance of patients with bilateral severe-to-profound sensorineural deafness. | Shaofeng Liu Fang Wang Peipei Chen Na Zuo Cheng Wu Jun Ma Jingjiang Huang Chuanxi Wang | 2019 | Journal of Otology2019，14，2： | 4 |
| 17 | High-precision time and frequency measurement method combining time-space conversion and different frequency phase detection显示文摘According to the time&space conversion relations and different frequency phase detection principle,an ultra-high precision time&frequency measurement method is proposed in this paper.The higher accuracy and stability of the speed of light and electromagnetic signals during the transmission in space or a specific medium enable the measurement of short time interval which uses the coincidence detection of signal’s transmission delay in length.The measurement precision better than 10 picoseconds can be easily obtained.The method develops the length vernier utilizing the stability of signal’s transmission delay,minimizes the fuzzy region of phase coincidence between the standard frequency signal and the measured signal,approaches the best phase coincidences and therefore improves the measurement precision which is higher than the precision provided by the traditional methods based on frequency processing.Besides,the method costs less than the traditional methods and can also solve the problem of the measurement of super-high frequency.Experimental results show the method can improve the measurement precision to 10 12/s in the time&frequency domain. | DU BaoQiang WANG YanFeng CUI GuangZhao GUO ShuTing DONG ShaoFeng LIU Dan | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，11： | 4 |
| 18 | Growth structures and growth strata of the Qianjiadian Basin in the western Yanshan fold and thrust belt, North China显示文摘The northwestward subduction of the Izanagi Plate beneath the eastern Eurasian Plate during the Late Mesozoic caused a series of compressional deformation events in the Yanshan fold and thrust belt(YFTB), but the tectonic deformation timing, tectonic properties and relationship between tectonic uplift and sediment accumulation in the intermontane basins continue to be debated. For this reason, the sedimentology, sediment provenance, and basin structure of the Qianjiadian Basin(QJB) in the northern Beijing region during the Late Jurassic and Early Cretaceous were studied in detail. The results suggest that a fault-propagation fold-type(FPFT) growth structure and growth strata developed on the western edge of the QJB and that the top part of Member 2 and Member 3 of the Tuchengzi Formation are growth strata controlled by the limb rotation mechanism. In two small thrust faults in the QJB, the Mesoproterozoic Xiamaling Formation is thrust over the Tuchengzi Formation, and these faults may have controlled the development of the fault-bend fold-type growth strata. An analysis of the 'source-to-sink' process suggests that the hanging wall succession of the Shangyi-Pingquan fault(SPF) was the main source area of the Late Jurassic to early Early Cretaceous strata in the QJB. A zircon206 Pb/238 U age of 140.8±2.4 Ma for the volcanic rocks at the bottom of the FPFT growth strata represents the timing of the initiation of FPFT growth structure development. The discovery of the FPFT growth structure and growth strata in the QJB indicate that the QJB was an intermontane flexural basin controlled by fold and thrust structures during the early Early Cretaceous. Near the E-W-trending SPF, the NE-SW-trending Qianjiadian thrust fault(QJTF) and two small intrabasinal thrust faults may constitute a unified right-lateral strike-slip system that formed in response to the northwestward flat subduction of the Izanagi Plate beneath the East Asian continent during the Jurassic-Early Cretaceous. | Xiaofei SHI Shaofeng LIU Chengfa LIN | 2019 | Science China Earth Sciences2019，62，7： | 4 |
| 19 | Simultaneous removal and oxidation of arsenic from water byδ-MnO 2 modified activated carbon显示文摘The ubiquitous arsenic in groundwater poses a great risk to human health due to its environmental toxicity and carcinogenicity.In the present work,a new adsorbent,δ-MnO2 modified activated carbon,was prepared,and its performance for the uptake of arsenate and arsenite species from aqueous solutions was investigated by batch experiments.Various techniques,including FESEM-EDX,p-XRD,XPS and BET surface area analysis,were employed to characterize the properties of the adsorbent and the arsenic adsorption mechanisms.The results showed thatδ-MnO2 covered on the surface and padded in the pores of the activated carbon.Adsorption kinetic studies revealed that approximately 90.1%and 76.8%of As(Ⅲ)and As(V),respectively,were removed by the adsorbent in the first 9 hr,and adsorption achieved equilibrium within 48 hr.The maximum adsorption capacities of As(V)and As(Ⅲ)at pH 4.0 calculated from Langmuir adsorption isotherms were 13.30 and 12.56 mg/g,respectively.The effect of pH on As(Ⅴ)and As(Ⅲ)removal was similar,and the removal efficiency significantly reduced with the increase of solution pH.Arsenite oxidation and adsorption kinetics showed that the As(Ⅴ)concentration in solution due to As(Ⅲ)oxidation and reductive dissolution of MnO2 increased rapidly during the first 12 min,and then gradually decreased.Based on the XPS analysis,nearly 93.3%of As(Ⅲ)had been oxidized to As(V)on the adsorbent surface and around 38.9%of Mn(Ⅳ)had been reduced to Mn(Ⅱ)after As(Ⅲ)adsorption.This approach provides a possible method for the purification of arsenic-contaminated groundwater. | Yulong Wang Hupeng Liu Shaofeng Wang Xuhui Li Xin Wang Yongfeng Jia | 2020 | Journal of Environmental Sciences2020，32，8： | 4 |
| 20 | Early dolomitisation of the Lower-Middle Ordovician cyclic carbonates in northern Tarim Basin, NW China显示文摘High-frequency metre-scale cycles are present within the Lower-Middle Ordovician carbonate successions in northern Tarim Basin, NW China. These metre-scale cycles were variably dolomitised from top to bottom. Three types of replacive dolomites were recognised, including dololaminite(very finely to finely crystalline, planar-s to nonplanar-a dolomite;type-1), patterned dolomite(finely crystalline, planar-s dolomite; type-2), and mottled dolomite(finely to medium crystalline,nonplanar-a(s) dolomite; type-3). Petrographic evidence indicate these dolomites were primarily deposited in supratidal to restricted subtidal environments, and formed in near-surface to shallow burial realms. Geochemically, all types of dolomites have similar δ13C and 87Sr/86 Sr ratios comparable to calcite precipitated in equilibrium with the Early-Middle Ordovician seawater. These geochemical attributes indicate that these dolomites were genetically associated and likely formed from connate seawater-derived brines. Of these, type-1 dolomite has δ18O values(.4.97‰ to.4.04‰ VPDB) slightly higher than those of normal seawater dolomite of the Early-Middle Ordovician age. Considering the absence of associated evaporites within type-1 dolomite, its parental fluids were likely represented by slightly evaporated(i.e., mesosaline to penesaline) seawater with salinity below that of gypsum precipitation. More depleted δ18O values(.7.74‰ to.5.20‰ VPDB) of type-2 dolomite and its stratigraphic position below type-1 dolomite indicate the generation of this dolomite from mesosaline to penesaline brines at higher temperatures in near-surface to shallow burial domains. Type-3 dolomite yields the most depleted δ18O values(–9.30‰to –7.28‰ VPDB), pointing to that it was most likely formed from coeval seawater-derived brines at highest temperatures in a shallow burial setting. There is a downward decreasing trend in δ18O values from type-1 through type-2 to type-3 dolomites, and in abundance of dolomites, indicating that the dolomitising fluids probably migrated downward from above and persisted into shallow burial conditions. | GUO Chuan CHEN DaiZhao DONG ShaoFeng QIAN YiXiong LIU CunGe | 2017 | Science China Earth Sciences2017，60，7： | 3 |
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