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| 1 | New eolian red clay sequence on the western Chinese Loess Plateau linked to onset of Asian desertification about 25 Ma ago显示文摘The expansion of inland Asia deserts has considerably influenced the environmental, social and economic activities in Asia. Aridification of inland Asia, especially timing of the initiation of Asian desertification, is a contentious topic in paleoclimatology. Late Cenozoic eolian loess-red clay sequences on the Chinese Loess Plateau, which possess abundant paleoclimatic and paleo-environmental information, can be regarded as an indicator of inland Asia desertification. Here we present a detailed magnetostratigraphic investigation of a new red clay sequence about 654 m in Zhuanglang located at the western Chinese Loess Plateau. Sedimentological, geochemical, mineralogical, and quartz morphological lines of evidence show that the red clay is of eolian origin. Magnetostratigraphic correlations indicate that this core sequence spans from 25.6 to 4.8 Ma, and typical eolian red clay appears as early as 25 Ma. This extends the lower limit of the red clay on the Chinese Loess Plateau from the previously thought early Miocene back into the late Oligocene. This new red clay record further implies that the inland Asia desertification was initiated at least by the late Oligocene. This sequence provides a unique high-resolution geological record for understanding the inland Asia desertification process since the late Oligocene. | QIANG XiaoKe AN ZhiSheng SONG YouGui CHANG Hong SUN YouBin LIU WeiGuo AO Hong DONG JiBao FU ChaoFeng WU Feng LU FengYan CAI YanJun ZHOU WeiJian CAO JunJi XU XinWen AI Li | 2011 | Science China Earth Sciences2011，54，1： | 73 |
| 2 | The Sunway TaihuLight supercomputer: system and applications显示文摘The Sunway Taihu Light supercomputer is the world's first system with a peak performance greater than 100 PFlops. In this paper, we provide a detailed introduction to the Taihu Light system. In contrast with other existing heterogeneous supercomputers, which include both CPU processors and PCIe-connected many-core accelerators(NVIDIA GPU or Intel Xeon Phi), the computing power of Taihu Light is provided by a homegrown many-core SW26010 CPU that includes both the management processing elements(MPEs)and computing processing elements(CPEs) in one chip. With 260 processing elements in one CPU, a single SW26010 provides a peak performance of over three TFlops. To alleviate the memory bandwidth bottleneck in most applications, each CPE comes with a scratch pad memory, which serves as a user-controlled cache. To support the parallelization of programs on the new many-core architecture, in addition to the basic C/C++and Fortran compilers, the system provides a customized Sunway Open ACC tool that supports the Open ACC2.0 syntax. This paper also reports our preliminary efforts on developing and optimizing applications on the Taihu Light system, focusing on key application domains, such as earth system modeling, ocean surface wave modeling, atomistic simulation, and phase-field simulation. | Haohuan FU Junfeng LIAO Jinzhe YANG Lanning WANG Zhenya SONG Xiaomeng HUANG Chao YANG Wei XUE Fangfang LIU Fangli QIAO Wei ZHAO Xunqiang YIN Chaofeng HOU Chenglong ZHANG Wei GE Jian ZHANG Yangang WANG Chunbo ZHOU Guangwen YANG | 2016 | Science China(Information Sciences)2016，59，7： | 45 |
| 3 | REE composition in scheelite and scheelite Sm-Nd dating for the Xuebaoding W-Sn-Be deposit in Sichuan显示文摘The scheelite with large size and euhedral shape from Xuebaoding, Sichuan Province is an ideal min- eral to study REE patterns and Sm-Nd dating of non-gold deposits. The scheelite has diameters of 1― 10 cm and colors of pale beige to deep orange. Most of these scheelites occur in association with beryl, cassiterite and muscovite. The rare earth elements indicate that scheelite samples from Xuebaoding W-Sn-Be deposits contain high concentrations of rare earth elements with total ΣREE+Y contents in the range of 369―1725 μg·g?1 and nearly all of these scheelite samples are enriched in LREE and depleted in HREE and have negative Eu anomalies. The REE patterns of the scheelites are similar to those of A-type granite with obvious tetrad effect, similar to that of type II scheelites. Based on reported fluid inclusion studies, the mineralizing-fluid of the Xuebaoding W-Sn-Be deposit indicates low Na activity. The REE patterns of the scheelite are probably controlled by partition coefficient in hydrothermal fluid. In the 147Sm/144Nd-143Nd/144Nd diagram, the scheelites show a linear array corresponding to an isochron age of 182.0±9.2 Ma (MSWD = 0.52). The Sm-Nd age represents the formation age of the scheelite and can indicate that the W, Sn and Be mineralization at Xuebaoding took place in the Early Yanshanian. The Sm-Nd dating result is important for the study of the multi-metal resources in western Sichuan Province. | LIU Yan DENG Jun LI ChaoFeng SHI GuangHai ZHENG AiLi | 2007 | Chinese Science Bulletin2007，52，18： | 25 |
| 4 | Ultra-low procedural blank and the single-grain mica Rb-Sr isochron dating显示文摘Both low procedural blank and high-precision measurements of isotopic ratios are crucial for the analysis of micro samples. This study reports a chemical procedure of ultra-low blank for the high precision measurement of Sr isotopic ratios on micro samples (<1 ng level) using a new-type thermal ionization mass spectrometer IsoProbe-T, with a case study of single-grain Rb-Sr isochron dating on phlogopite from the Fuxian kimberlite in Liaoning Province. This method can be employed in studies of high resolution Rb-Sr geochronology and Sr isotopic geochemistry and thus will broaden application of the Rb-Sr isotopic system to earth sciences. | LI Qiuli HEN Fukun WANG Xiuli LI Xianghui LI Chaofeng | 2005 | Chinese Science Bulletin2005，50，24： | 15 |
| 5 | Design and experimental study of a micro-groove grinding wheel with spray cooling effect显示文摘The effectiveness of grinding fluid supply has a crucial impact on grinding quality and efficiency in high speed grinding. In order to improve the cooling and lubrication, through in-depth research of self-inhaling internal cooling method and intermittent grinding mechanism, a new spray cooling method used in high speed grinding is proposed. By referring to the structure of bowlshaped dispersion disk, the grinding wheel matrix with atomization ability is designed; through studying heat transfer of droplet collision and the influence of micro-groove on the boiling heat transfer, grinding segment with micro-groove is designed to enhance the heat flux of coolant and achieve maximum heat transfer between droplets and grinding contact zone. High-speed grinding experiments on GH4169 with the developed grinding wheel are carried out. The results show that with the micro-groove grinding wheel just 5.4% of pump outlet flow rate and 0.5% of spindle energy is needed to reduce the grinding temperature to 200 C, which means the developed grinding wheel makes cooling high efficient and low energy consuming. | Shi Chaofeng Li Xun Chen Zhitong | 2014 | Chinese Journal of Aeronautics2014，27，2： | 14 |
| 6 | Processing of advanced thermoelectric materials显示文摘Last two decades have witnessed significant progress in thermoelectric research,to which materials processing has crucial contributions.Compared with traditional zone-melting method used for fabricating bismuth telluride alloys,new powder-based processes have more freedom for manipulating nanostructures and nanocomposites.Thermoelectric performance enhancement is realized in most thermoelectric materials by introducing fine-grained and nano-composite structures with accurately controlled compositions.This review gives a comprehensive summary on the processing aspects of thermoelectric materials with three focuses on the powder synthesis,advanced sintering process and the formation of nano structures in bulk materials. | LI JingFeng PAN Yu WU ChaoFeng SUN FuHua WEI TianRan | 2017 | Science China(Technological Sciences)2017，60，9： | 13 |
| 7 | Regional Distribution and Sustainable Development Strategy of Mineral Resources in China显示文摘This paper summarizes the distribution and production layout of the major mineral resources in China,including coal,iron ore,copper and bauxite,from a national perspective.It also identifies the incompatibility between the mineral resources distribution and regional economic development.Significant issues with China's mineral resource industry cause challenges for the sustainable development of both the mining industry and the national socio-economy.The sustainability of regional mineral resources and the environmental pollution by mining in the western China were also analyzed.Results show that the distribution of China's mineral resources is misaligned with its regional layout of economic development.China's mineral resources have been over-exploited,and the mineral resources production in the eastern China is unsustainable.The continuously expanding production of mineral resources in the western China has heavily endangered the ecological environment.We propose strategies to boost the sustainable development of mineral resources,including measures to accelerate economic development and enhance the sustainability of domestic mineral resources.We also offer suggestions for scientifically planning the mineral resource prospecting and exploitation and regional economic layout,as well as for proactively undertaking industry transfer in the eastern China and raising the environmental benchmark requirements for the mineral industry in the central and western China. | LI Chaofeng WANG Anjian CHEN Xiaojin CHEN Qishen ZHANG Yanfei LI Ying | 2013 | Chinese Geographical Science2013，23，4： | 11 |
| 8 | Development and validation of an endoscopic images-based deep learning model for detection with nasopharyngeal malignancies显示文摘Background:Due to the occult anatomic location of the nasopharynx and frequent presence of adenoid hyperpla-sia,the positive rate for malignancy identification during biopsy is low,thus leading to delayed or missed diagnosis for nasopharyngeal malignancies upon initial attempt.Here,we aimed to develop an artificial intelligence tool to detect nasopharyngeal malignancies under endoscopic examination based on deep learning.Methods:An endoscopic images-based nasopharyngeal malignancy detection model(eNPM-DM)consisting of a fully convolutional network based on the inception architecture was developed and fine-tuned using separate training and validation sets for both classification and segmentation.Briefly,a total of 28,966 qualified images were collected.Among these images,27,536 biopsy-proven images from 7951 individuals obtained from January 1st,2008,to December 31st,2016,were split into the training,validation and test sets at a ratio of 7:1:2 using simple randomiza-tion.Additionally,1430 images obtained from January 1st,2017,to March 31st,2017,were used as a prospective test set to compare the performance of the established model against oncologist evaluation.The dice similarity coef-ficient(DSC)was used to evaluate the efficiency of eNPM-DM in automatic segmentation of malignant area from the background of nasopharyngeal endoscopic images,by comparing automatic segmentation with manual segmenta-tion performed by the experts.Results:All images were histopathologically confirmed,and included 5713(19.7%)normal control,19,107(66.0%)nasopharyngeal carcinoma(NPC),335(1.2%)NPC and 3811(13.2%)benign diseases.The eNPM-DM attained an overall accuracy of 88.7%(95%confidence interval(CI)87.8%-89.5%)in detecting malignancies in the test set.In the prospective comparison phase,eNPM-DM outperformed the experts:the overall accuracy was 88.0%(95%CI 86.1%-89.6%)vs.80.5%(95%CI 77.0%-84.0%).The eNPM-DM required less time(40 s vs.110.0±5.8 min)and exhibited encouraging performance in automatic segmentation of nasopharyngeal malignant area from the background,with an average DSC of 0.78±0.24 and 0.75±0.26 in the test and prospective test sets,respectively.Conclusions:The eNPM-DM outperformed oncologist evaluation in diagnostic classification of nasopharyngeal mass into benign versus malignant,and realized automatic segmentation of malignant area from the background of nasopharyngeal endoscopic images. | Chaofeng Li Bingzhong Jing Liangru Ke Bin Li Weixiong Xia Caisheng He Chaonan Qian Chong Zhao Haiqiang Mai Mingyuan Chen Kajia Cao Haoyuan Mo Ling Guo Qiuyan Chen Linquan Tang Wenze Qiu Yahui Yu Hu Liang Xinjun Huang Guoying Liu Wangzhong Li Lin Wang Rui Sun Xiong Zou Shanshan Guo Peiyu Huang Donghua Luo Fang Qiu Yishan Wu Yijun Hua Kuiyuan Liu Shuhui Lv Jingjing Miao Yanqun Xiang Ying Sun Xiang Guo Xing Lv | 2018 | Cancer Communications2018，38，1： | 9 |
| 9 | MASLOV-TYPE INDEX THEORYFOR SYMPLECTIC PATHS AND SPECTRAL FLOW(II)显示文摘Based on the spectral now and the stratification structures of the symplectic group Sp(2n, c) , the Maslov-type index theory and its generalization, the w-index theory parameterized by all ω on the unit circle, for arbitrary paths in Sp(2n, C) are established. Then the Bott-type iteration formula of the Maslov-type indices for iterated paths in Sp(2n, C) is proved, and the mean index for any path in Sp(2n, C) is defined. Also, the relation among various Maslov-type index theories is studied. | LONG YIMING ZHU CHAOFENG | 2000 | Chinese Annals of Mathematics,Series B2000，21，1： | 8 |
| 10 | Energy storage through intercalation reactions:electrodes for rechargeable batteries显示文摘Electrochemical energy storage has been an important enabling technology for modern electronics of all kinds,and will grow in importance as more electric vehicles and grid-scale storage systems are deployed.We briely review the history of intercalation electrodes and basic concepts pertaining to bateries based on intercalation reactions.hen we summarize how the critical performance metrics—energy density,power density,safety and stability—relate back to electrode materials properties,and how these materials properties are related to fundamental chemical and physical structure relationships highlighted with the most recent research advancement.Challenges and avenues for further research have been highlighted throughout. | Robert C.Massé Chaofeng Liu Yanwei Li Liqiang Mai Guozhong Cao | 2017 | National Science Review2017，4，1： | 8 |
| 11 | Development and Analysis of an Electrically Actuated Lower Extremity Assistive Exoskeleton显示文摘一架电子上激活的更低的极限皮骨骼被开发,在哪个当有弹性的元素连接的另外的关节消极地被激活时,仅仅膝关节活跃地被激活。这份报纸描述批评设计标准并且介绍设计的进程和使活动系统的计算。一台灵活物理 Human-Robot-Interaction (pHRI ) 测量设备被设计并且适用检测人的运动,它包括纳入连接手铐的内部表面的二个力量传感器和二个气囊。联机适应 pHRI 最小化控制策略被建议并且实现了驱使机器的皮骨骼系统跟随人的手足的运动轨道。测量 pHRI 信息被变化加权的一般水准(VWA ) 方法熔化。pHRI 和控制转矩的吝啬的方形的价值(MSV ) 被利用评估皮骨骼的表演。改进舒适水平和还原剂精力消费,当控制法律被设计时,严肃赔偿被考虑。最后,实际实验在健康用户上被执行。试验性的结果证明建议系统能帮助人走,构画出的控制策略有效、有效。 | Yi Long Zhijiang Du Chaofeng Chen Weidong Wang Long He Xiwang Mao Guoqiang Xu Guangyu Zhao Xiaoqi Li Wei Dong | 2017 | Journal of Bionic Engineering2017，14，2： | 7 |
| 12 | Dynamic Characteristics of Multi-degrees of Freedom System Rotor-bearing System with Coupling Faults of Rub-impact and Crack显示文摘Extensive studies on rotor systems with single or coupled multiple faults have been carried out. However these studies are limited to single-span rotor systems. A finite element model for a complex rotor-bearing system with coupled faults is presented. The dynamic responses of the rotor-bearing system are obtained by using the rotor dynamics theory and the modern nonlinear dynamics theory in connection with the continuation-shooting algorithm(commonly used for obtaining a periodic solution for a nonlinear system) for a range of rub-impact clearances and crack depths. The stability and Hopf instability of the periodic motion of the rotor-bearing system with coupled faults are analyzed by using the procedure described. The results indicate that the finite element method is an effective way for determining the dynamic responses of such complex rotor-bearing systems. Further for a rotor system with rub-impact and crack faults, the influences of the clearances are significantly different for different rub-impact stiffness. On the contrary, the influence of crack depths is rather small. The instability speeds of the rotor-bearing system increase due to the presence of the crack fault. The results obtained using the new finite element model, presented for computation and analysis of dynamic responses of the rotor-bearing systems with coupled faults, are in accordance with measurements in experiment. The formulations given can be used for diagnosis of faults, vibration control, and safe and stable operations of real rotor-bearing systems. | REN Zhaohui ZHOU Shihua LI Chaofeng WEN Bangchun | 2014 | Chinese Journal of Mechanical Engineering2014，27，4： | 7 |
| 13 | NECK LEAF 1, a GATA type transcription factor, modulates organogenesis by regulating the expression of multiple regulatory genes during reproductive development in rice显示文摘在 monocot 米饭种类 Oryza sativa L. ,最惹人注目的词法过程之一在繁殖开发期间是有上面的 internodes (合众国际社) 的顺序的延伸的圆锥花序开发的同时发生。阐明内在的分子的机制,我们克隆米饭基因颈叶 1 (NL1 ) ,什么时候变异,它在 flowering 时间,有簇叶丛生的苞的更小的圆锥花序和反常合众国际社延伸模式导致延期。NL1 基因与一个单个锌手指领域,和它的抄本编码一个 GATA 类型抄写因素在苞 primordia 主要被检测,它通常在野类型的植物堕落。在转基因的植物的 NL1 的 Overexpression 经常产生严重生长延迟,不太植物的 phytomers 和更小的叶子,建议 NL1 起在器官区别的一个重要作用。PLASTOCHRON1 (PLA1 ) 的新奇变异的等位基因,知道在调整叶开始起一个关键作用的基因,在这研究被识别。基因分析表明了在 nl1 和 pla1 之间的一个相互作用,与 PLA1 在上游的代理的 NL1。表示水平和 PLA1 的空间模式被发现在 nl1 被改变变异。而且, flowering, Hd3a 和 OsMADS1 的二个管理者的表示,也在 nl1 异种被影响。根据这些调查结果,我们建议 NL1 是通过在米饭在繁殖开发期间调整 PLA1 和另外的规章的基因的表示调制并且协调 organogenesis 的一个内在的因素。 | Liping Wang Hengfu Yin Qian Qian Jun Yang Chaofeng Huang Xiaohe Hu Da Luo | 2009 | Cell Research2009，19，5： | 6 |
| 14 | High-yield preparation of robust gold nanoshells on silica nanorattles with good biocompatiblity显示文摘Although gold nanoshells are widely considered as one of the promising photothermal nanomaterials used for biomedicine, the high cost, low yield and poor stability severely limit their potential application in clinical trials.Herein, robust gold nanoshells on silica nanorattles(GSNs)were easily prepared in a high yield by an improved seedmediated method employing polyvinylpyrrolidone(PVP) as a stabilizing and capping agent. The present method is very simple, effective and reproducible and can well control the growth process of gold nanoshells. The as-prepared GSNs have a narrow size distribution(<10 % in standard deviation). Furthermore, the utilization rate of Au in the solution used for the growth of gold nanoshells increases by 70 %than that in previous method. The resultant GSNs have a good structural stability after placing over 6 months due to the protection of PVP. More importantly, in vivo and in vitro toxic studies indicate that the GSNs have good biocompatibility. We believe that our preparation method will remarkably promote the use of gold nanoshells for biomedicine. | Changhui Fu Chaofeng He Longfei Tan Shunhao Wang Lu Shang Linlin Li Xianwei Meng Huiyu Liu | 2016 | Science Bulletin2016，61，4： | 5 |
| 15 | Simulations and Experimental Investigation on Motion Stability of a Flexible Rotor-bearing System with a Transverse Crack显示文摘In the classical process for stability studies on the rotor-bearing system with crack faults,the simple discrete model is adopted for research on such problems,which neglect some needful dynamical influence factor,such as the material damping,shearing effect and gyroscopic effects,etc.Therefore,it is necessary to find a precise calculation model for simulation of the rotor-bearing system with cracks faults.In this paper,instead of the traditional simple discrete model,finite element(FE)model is adopted to investigate the motion stability of a nonlinear rotor system with crack fault.According to finite element theory,the FE model of the cracked rotor system is established firstly.It should be pointed out that the element where the crack occurs is modeled by a particular crack element and the supports at both ends are simulated by two nonlinear loads.Then,based on dimensionless and dimensionality reduction,the Newmark-βmethod and the shooting method are employed to study the effect of eccentricity and the depth of crack on instability speed and bifurcation feature.Furthermore,the simulation results are verified by some corresponding experiments.The simulation and experimental results show that instability speed does not change monotonically,but decreases firstly and then increases when the amount of eccentricity increases.Moreover,as the type of instability changes,the instability speed jumps concomitantly.Additionally,the presence of crack fault can disturb the oil whirl,as a result,instability speed tends to increase slightly,but it does not affect the type of instability and jumping phenomenon.This research presents an effective and convenient method which uses the finite element method(FEM)to research the motion stability of the nonlinear rotor-bearing system with cracked faults and other nonlinear force,and the proposed method can provide a theoretical reference for stability analysis and vibration control in more complex relevant rotor-bearing system. | LI Chaofeng YU Hexing ZHOU Shihua WEN Bangchun | 2013 | Chinese Journal of Mechanical Engineering2013，26，6： | 5 |
| 16 | Co3O4 modified Ag/g-C3N4 composite as a bifunctional cathode for lithium-oxygen battery显示文摘Rechargeable lithium-oxygen(Li-O2)batteries have appeal to enormous attention because they demonstrate higher energy density than the state-of-the-art Li-ion batteries.Whereas,their practical application is impeded by several challenging problems,such as the low energy round trip efficiencies and the insufficient cycle life,due to the cathode passivation caused by the accumulation of discharge products.Developing efficient catalyst for oxygen reduction and evolution reactions is effective to reduce the overpotentials in Li-O2cells.In our work,we report a Co3O4modified Ag/g-C3N4nanocomposite as a bifunctional cathode catalyst for Li-O2cells.The g-C3N4substrate prevents the accumulation of Ag and Co3O4nanoparticles and the presence of Ag NPs improves the surface area of g-C3N4and electronic conductivity,significantly improving the oxygen reduction/evolution capabilities of Co3O4.Due to a synergetic effect,the Ag/g-C3N4/Co3O4nanocomposite demonstrates a higher catalytic activity than each individual constituent of Co3O4or Ag/g-C3N4for the ORR/OER on as catalysts in Li-O2cells.As a result,the Ag/gC3N4/Co3O4composite shows impressive electrochemical performance in a Li-O2battery,including high discharge capacity,small gap between charge and discharge potential,and high cycling stability. | Qi Guo Chenwei Zhang Chaofeng Zhang Sen Xin Pengchao Zhang Qiufan Shi Dawei Zhang Ya You | 2020 | Journal of Energy Chemistry2020，29，2： | 4 |
| 17 | Enhanced Reversible Zinc Ion Intercalation in Deficient Ammonium Vanadate for High-Performance Aqueous Zinc-Ion Battery显示文摘Ammonium vanadate with bronze structure(NH_(4)V_(4)O_(10))is a promising cathode material for zinc-ion batteries due to its high specific capacity and low cost.However,the extraction of NH^(+)_(4) at a high voltage during charge/discharge processes leads to irreversible reaction and structure degradation.In this work,partial NH^(+)_(4) ions were pre-removed from NH_(4)V_(4)O_(10) through heat treatment;NH_(4)V_(4)O_(10) nanosheets were directly grown on carbon cloth through hydrothermal method.Defi-cient NH_(4)V_(4)O_(10)(denoted as NVO),with enlarged interlayer spacing,facilitated fast zinc ions transport and high storage capacity and ensured the highly reversible electrochemical reaction and the good stability of layered structure.The NVO nanosheets delivered a high specific capac-ity of 457 mAh g^(−1) at a current density of 100 mA g^(−1) and a capacity retention of 81%over 1000 cycles at 2 A g^(−1).The initial Coulombic efficiency of NVO could reach up to 97%compared to 85%of NH_(4)V_(4)O_(10) and maintain almost 100%during cycling,indicating the high reaction reversibility in NVO electrode. | Quan Zong Wei Du Chaofeng Liu Hui Yang Qilong Zhang Zheng Zhou Muhammad Atif Mohamad Alsalhi Guozhong Cao | 2021 | Nano-Micro Letters2021，13，8： | 4 |
| 18 | The effect of nitrogen annealing on lithium ion intercalation in nickel-doped lithium trivanadate显示文摘The communication reports an exploratory experimental study on the effects of nitrogen annealing on lithium ion intercalation in nickel-doped lithium trivanadate cathodic electrodes for lithium ion batteries. It shows good rate performance with discharge capacities of 348.6,252.6, 191.9 and 96.7 m Ah g^(-1)at 0.2, 0.5, 1 and 5 C,respectively. Nitrogen annealing resulted in the formation of parasitic secondary-phase Li V_2O_5 and appreciably increased tetravalent vanadium ions compensated with oxygen vacancies, which would enhance the electronic conductivity and lithium ion diffusivity and promote the interface interaction and deintercalation process, and thus lead to the enhanced lithium ion intercalation properties.The possible impacts of the parasitic secondary-phase Li V_2O_5 on the lithium ion intercalation performance have also been discussed. | Yaguang Liu Cuiping Zhang Chaofeng Liu Huanqiao Song Xihui Nan Guozhong Cao | 2016 | Science Bulletin2016，61，8： | 4 |
| 19 | Mild Breakthrough Infection in a Healthcare Professional Working in the Isolation Area of a Hospital Designated for Treating COVID-19 Patients—Shaanxi Province,China,March,2021显示文摘Summary What is already known about this topic?Healthcare workers are at high risk of acquiring COVID-19 from occupational exposure to COVID-19 virus during their daily medical service work.Excellent infection prevention and control measures and adequate personal protective equipment(PPE)are essential to reduce the risk of hospital-acquired COVID-19. | Chaofeng Ma Songtao Xu Yecheng Yao Pengbo Yu You Xu Rui Wu Hailong Chen Xiaoping Dong | 2021 | China CDC weekly2021，3，19： | 4 |
| 20 | Constraints on the Ediacaran-Cambrian boundary in deep-water realm in South China: Evidence from zircon CA-ID-TIMS U-Pb ages from the topmost Liuchapo Formation显示文摘The placement of the Ediacaran-Cambrian boundary in deep-water realm in South China and the high-precision temporal framework for the Ediacaran-Cambrian transition in this region have not yet been completely solved. Recently, we have found two K-bentonite beds in the top of the Liuchapo Formation at the Pingyin section, Guizhou Province. It provides an opportunity for constructing the temporal framework of the transitional strata on the Yangtze Platform in South China and for determining the Ediacaran-Cambrian boundary in this area. In this study, we conducted high-precision CA-ID-TIMS U-Pb dating on zircons from the two K-bentonites. The ages of the two K-bentonites were precisely constrained at 536.40±0.47/1.1/1.2 Ma(2σ, n=7, MSWD=0.92) and 541.48±0.46/1.1/1.2 Ma(2σ, n=8, MSWD=1.3). Combining the geochronological results with organic carbon isotope data of chert in the topmost Liuchapo Formation from the section, we suggest that the EdiacaranCambrian boundary should be consistent with a significant negative organic carbon isotope excursion between the two Kbentonites. The scheme of the Ediacaran-Cambrian boundary in this study is of great significance for global correlation, and further for unravelling the information of the terminal Ediacaran-early Cambrian ocean. | Wei WANG Mingzhong ZHOU Zhuyin CHU Junjie XU Chaofeng LI Taiyi LUO Jinghui GUO | 2020 | Science China Earth Sciences2020，63，8： | 4 |
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