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| 1 | SIMS U-Pb zircon age of a tuff layer in the Meishucun section, Yunnan, southwest China: Constraint on the age of the Precambrian-Cambrian boundary显示文摘Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out closely following the guidance of cathodoluminescence images, and the majority of analyses were conducted on the oscillatory zircon grains. Thirteen measurements yield a highly reliable Concordia U-Pb age of 536.7 ± 3.9 Ma for the Bed 5 horizon. A grand mean of 206Pb/238U age of 535.2± 1.7 Ma (MSWD = 0.53) is calculated based on 13 concordant SIMS measurements of this study and 4 nano-SIMS measurements of Sawaki et al., which is the best estimate of the deposition age of the tuff layer within Bed 5 in the Meishucun section. This age has provided a robust age constraint on the significant Precambrian-Cambrian boundary strata in southern China, which independently suggested the placement of the Precambrian-Cambrian boundary at the bottom of the Xiaowaitoushan Member (Marker A). | RiXiang Zhu XianHua Li XianGuang Hou YongXin Pan Fei Wang ChengLong Deng HuaiYu He | 2009 | Science China Earth Sciences2009，52，9： | 24 |
| 2 | Ultrafast and broadband photodetectors based on a perovskite/organic bulk heterojunction for large-dynamic-range imaging显示文摘Organic-inorganic hybrid perovskite(OIHP)photodetectors that simultaneously achieve an ultrafast response and high sensitivity in the near-infrared(NIR)region are prerequisites for expanding current monitoring,imaging,and optical communication capbilities.Herein,we demonstrate photodetectors constructed by OIHP and an organic bulk heterojunction(BHJ)consisting of a low-bandgap nonfullerene and polymer,which achieve broadband response spectra up to 1μm with a highest external quantum efficiency of approximately 54%at 850 nm,an ultrafast response speed of 5.6 ns and a linear dynamic range(LDR)of 191 dB.High sensitivity,ultrafast speed and a large LDR are preeminent prerequisites for the practical application of photodetectors.Encouragingly,due to the high-dynamicrange imaging capacity,high-quality visible-NIR actual imaging is achieved by employing the OIHP photodetectors.We believe that state-of-the-art OIHP photodetectors can accelerate the translation of solution-processed photodetector applications from the laboratory to the imaging market. | Chenglong Li Hailu Wang Fang Wang Tengfei Li Mengjian Xu Hao Wang Zhen Wang Xiaowei Zhan Weida Hu Liang Shen | 2020 | Light(Science & Applications)2020，9，1： | 13 |
| 3 | Genesis of the Hongzhen metamorphic core complex and its tectonic implications显示文摘The Hongzhen metamorphic core complex is situated in the Yangtze plate to the east of the Dabie oro- genic belt. Its ductile detachment zone in the foot wall overprints on the metamorphic complex of the Proterozoic Dongling Group. The present profile of the ductile shear zone with consistent SW-dipping mineral elongation lineation shows antiform and reversed S-shape from northeast to southwest respectively. Exposure structures, microstructures and quartz C-axis fabric all indicate top-to-SW movement for the ductile shear zone. Recrystallisation types of quartz and feldspar in the mylonites demonstrate that the shear zone was developed under the amphibolite facies condition and at mid-crust levels. The metamorphic core complex formed in the Early Cretaceous with a muscovite plateau age of 124.8±1.2 Ma. Regional NE-SW extension along a SW-dipping, gentle detachment zone was responsible for formation of the core complex. Intrusion of the Hongzhen granite with a biotite plateau age of 124.8±1.2 Ma rendered the ductile shear zone curved, uplifted and final localization of the core complex. The Hongzhen metamorphic core complex suggests that the Early Cretaceous magma- tism in this region took place under the condition of regional extension and the eastern Yangtze plate also experienced lithospheric thinning. | ZHU Guang XIE ChengLong XIANG BiWei HU ZhaoQi WANG YongSheng LI Xing | 2007 | Science China Earth Sciences2007，50，5： | 10 |
| 4 | Terahertz metasurface zone plates with arbitrary polarizations to a fixed polarization conversion显示文摘Metasurfaces that can realize the polarization manipulation of electromagnetic waves on the sub-wavelength scale have become an emerging research field.Here,a novel strategy of combining the metasurface and Fresnel zone plate to form a metasurface zone plate is proposed to realize the conversion from nearly arbitrary polarizations to a fixed polarization.Specifically,when one polarized wave is incident on adjacent ring zones constructed by different types of meta-atoms,the transmitted waves generated by odd-numbered and even-numbered ring zones converge at the same focus and superimpose to generate a fixed polarized wave.As function demonstrations,we have designed two types of metasurface zone plates:one is a focused linear polarizer,and the other can convert nearly arbitrary polarized waves into focused circularly polarized waves.The simulated and measured results are consistent with theoretical expectations,suggesting that the proposed concept is flexible and feasible.Our work provides an alternative platform for polarization manipulation and may vigorously promote the development of polarization photonic devices. | Zhen Yue Jitao Li Jie Li Chenglong Zheng Jingyu Liu Guocui Wang Hang Xu Mingyang Chen Yating Zhang Yan Zhang Jianquan Yao | 2022 | Opto-Electronic Science2022，1，3： | 9 |
| 5 | Dynamic phase assembled terahertz metalens for reversible conversion between linear polarization and arbitrary circular polarization显示文摘If a metalens integrates the circular polarization(CP)conversion function,the focusing lens together with circular-polariz-ing lens(CPL)in traditional cameras may be replaced by a metalens.However,in terahertz(THz)band,the reported metalenses still do not obtain the perfect and strict single-handed CP,because they were constructed via Pancharatnam-Berry phase so that CP conversion contained both left-handed CP(LCP)and right-handed CP(RCP)components.In this paper,a silicon based THz metalens is constructed using dynamic phase to obtain single-handed CP conversion.Also,we can rotate the whole metalens at a certain angle to control the conversion of multi-polarization states,which can simply manipulate the focusing for incident linear polarization(LP)THz wave in three polarization conversion states,in-cluding LP without conversion,LCP and RCP.Moreover,the polarization conversion behavior is reversible,that is,the THz metalens can convert not only the LP into arbitrary single-handed CP,but also the LCP and RCP into two perpen-dicular LP,respectively.The metalens is expected to be used in advanced THz camera,as a great candidate for tradi-tional CPL and focusing lens group,and also shows potential application in polarization imaging with discriminating LCP and RCP. | Jitao Li Guocui Wang Zhen Yue Jingyu Liu Jie Li Chenglong Zheng Yating Zhang Yan Zhang Jianquan Yao | 2022 | Opto-Electronic Advances2022，5，1： | 9 |
| 6 | Evidence of fire use of late Pleistocene humans from the Huanglong Cave, Hubei Province, China显示文摘Since 2004, three excavations have been carried out at a late Pleistocene human fossil site of Huanglong Cave in Yunxi County, Hubei Province of China, which unearthed seven human teeth, dozens of stone tools, mammal fossils and other evidence indicating human activities. During the third excavation in 2006, in the same layer as the human teeth, we found some patches of black materials embed- ded in the deposit. We doubted that this black deposit layer is the remains of burning or even human use of fire at the cave. To further explore the possibility of human fire use at the Huanglong Cave, we examined samples directly taken from the black deposit layer and compared them with samples taken from several places in the cave using three methods: micromorphology, element content determination and deposit temperature analysis. Our results indicate that the contents of carbon element in the black deposit reach 64.59%―73.29%. In contrast, contents of carbon element of the comparative samples from other parts in the cave are only 5.82%―9.49%. The micromorphology analysis of the black deposit samples reveals a plant structure like axial parenchyma, fibrocyte, uniseriate ray and vessel. High-temperature magnetic susceptibility measurements suggest that the stratum possibly underwent a high temperature in the nature. Based on these lab analyses, we are sure that the black layer in the Huanglong Cave is the remains of fire and combustion did occur in the cave 100000 years ago. Taking other evidence of human activities found in the Huanglong Cave into consideration, we believe that the evidence of fire from the Huanglong Cave was caused by the human activities of controlled use of fire. | LIU Wu WU XianZhu LI YiYin DENG ChengLong WU XiuJie PEI ShuWen | 2009 | Chinese Science Bulletin2009，54，2： | 8 |
| 7 | Lake geochemistry reveals marked environmental change in Southwest China during the Mid Miocene Climatic Optimum显示文摘中间中新世的气候的最佳(MMCO;~ 15-17 ? 妈) 是标点的短期的气候的温暖的事件之一新生代长期的冷却趋势。因为有这个事件的很少的陆上的记录,大多数我们的理解来自海洋的核心。在这份报告,我们首先介绍修订标明日期的新 palaeomagnetic 数据我们的 400 ? 在 Wenshan (云南) 的 m 厚的湖的节,以前想了晚中新世。这些新数据建议老年, ca。15.2-16.5 ? 妈,与 MMCO 与一致。我们测量了 13 体积有机物上的 C (13 C 器官的碳(TOC ) ,全部的氮(TN ) 和在高度的 C/N 比率取样的 org ), 总数分辨率:(1 ) 重建在湖集水区域的 palaeoenvironmental 变化,并且(2 ) 推断为这些变化负责的机制。我们的结果证明所有四个 geochemical 参数证明一个强壮的环境变化发生在节的中间附近,立即在在 15.97 点的 C5Cn/C5Br 地磁气的颠倒和早 / 中间中新世的边界以后 ? 妈。我们建议环境移动可能由于在气候的一个变化的联合,它变得更凉爽,和在有机物在湖以内骑车的一个变化。这研究提供新卓见进 MMCO 并且证明尽管 MMCO 通常是一个温暖的事件,它也是气候的不稳定性和突然的环境变化的一倍。 | Julie Lebreton-Anberree Shihu Li Shu-Feng Li Robert A. Spicer Shi-Tao Zhang Tao Su Chenglong Deng Zhe-Kun Zhou | 2016 | Science Bulletin2016，61，11： | 8 |
| 8 | High-temperature treatment induced carbon anode with ultrahigh Na storage capacity at low-voltage plateau显示文摘Sodium-ion batteries(NIBs) show great prospect on the energy storage applications benefiting from their low cost and the abundant Na resources despite the expected lower energy density compared with lithium-ion batteries(LIBs). To further enhance the competitive advantage, especially in energy density,developing the high-capacity carbon anode materials can be one of the effective approaches to realize this goal. Herein, we report a novel carbon anode made from charcoal with a high capacity of ~400 m Ah g^(-1), wherein about 85%(>330 mAh g^(-1)) of its total capacity is derived from the long plateau region below ~0.1 V, which differs from those of typical hard carbon materials(~300 m Ah g^(-1)) in NIBs but is similar to the graphite anode in LIBs. When coupled with air-stable Na_(0.9)Cu_(0.22)e_(0.30)Mn_(0.48)O_2 oxide cathode, a high-energy density of ~240 Wh kg^(-1) is achieved with good rate capability and cycling stability. The discovery of this promising carbon anode is expected to further improve the energy density of NIBs towards large-scale electrical energy storage. | Chenglong Zhao Qidi Wang Yaxiang Lu Baohua Li Liquan Chen Yong-Sheng Hu | 2018 | Science Bulletin2018，63，17： | 7 |
| 9 | Rapid drift of the Tethyan Himalaya terrane before two-stage India-Asia collision显示文摘The India-Asia collision is an outstanding smoking gun in the study of continental collision dynamics.How and when the continental collision occurred remains a long-standing controversy.Here we present two new paleomagnetic data sets from rocks deposited on the distal part of the Indian passive margin,which indicate that the Tethyan Himalaya terrane was situated at a paleolatitude of∼19.4°S at∼75 Ma and moved rapidly northward to reach a paleolatitude of∼13.7°N at∼61 Ma.This implies that the Tethyan Himalaya terrane rifted from India after∼75 Ma,generating the North India Sea.We document a new two-stage continental collision,first at∼61 Ma between the Lhasa and Tethyan Himalaya terranes,and subsequently at∼53−48 Ma between the Tethyan Himalaya terrane and India,diachronously closing the North India Sea from west to east.Our scenario matches the history of India-Asia convergence rates and reconciles multiple lines of geologic evidence for the collision. | Jie Yuan Zhenyu Yang Chenglong Deng Wout Krijgsman Xiumian Hu Shihu Li Zhongshan Shen Huafeng Qin Wei An Huaiyu He Lin Ding Zhengtang Guo Rixiang Zhu | 2021 | National Science Review2021，8，7： | 7 |
| 10 | Human ACE2-Functionalized Gold“Virus-Trap”Nanostructures for Accurate Capture of SARS-CoV-2 and Single-Virus SERS Detection显示文摘The current COVID-19 pandemic urges the extremely sensitive and prompt detection of SARS-CoV-2 virus.Here,we present a Human Angiotensin-converting-enzyme 2(ACE2)-functionalized gold“virus traps”nanostructure as an extremely sensitive SERS biosensor,to selectively capture and rapidly detect S-protein expressed coronavirus,such as the current SARS-CoV-2 in the contaminated water,down to the single-virus level.Such a SERS sensor features extraordinary 106-fold virus enrichment originating from high-affinity of ACE2 with S protein as well as“virus-traps”composed of oblique gold nanoneedles,and 109-fold enhancement of Raman signals originating from multi-component SERS effects.Furthermore,the identification standard of virus signals is established by machine-learning and identification techniques,resulting in an especially low detection limit of 80 copies mL^(−1) for the simulated contaminated water by SARS-CoV-2 virus with complex circumstance as short as 5 min,which is of great significance for achieving real-time monitoring and early warning of coronavirus.Moreover,here-developed method can be used to establish the identification standard for future unknown coronavirus,and immediately enable extremely sensitive and rapid detection of novel virus. | Yong Yang Yusi Peng Chenglong Lin Li Long Jingying Hu Jun He Hui Zeng Zhengren Huang Zhi-Yuan Li Masaki Tanemura Jianlin Shi John R.Lombardi Xiaoying Luo | 2021 | Nano-Micro Letters2021，13，7： | 6 |
| 11 | Full-space Cloud of Random Points with a Scrambling Metasurface显示文摘With the rapid progress in computer science,including artificial intelligence,big data and cloud computing,full-space spot generation can be pivotal to many practical applications,such as facial recognition,motion detection,augmented reality,etc.These opportunities may be achieved by using diffractive optical elements(DOEs)or light detection and ranging(LIDAR).However,DOEs suffer from intrinsic limitations,such as demanding depth-controlled fabrication techniques,large thicknesses(more than the wavelength),Lambertian operation only in half space,etc.LIDAR nevertheless relies on complex and bulky scanning systems,which hinders the miniaturization of the spot generator.Here,inspired by a Lambertian scatterer,we report a Hermitian-conjugate metasurface scrambling the incident light to a cloud of random points in full space with compressed information density,functioning in both transmission and reflection spaces.Over 4044 random spots are experimentally observed in the entire space,covering angles at nearly 90°.Our scrambling metasurface is made of amorphous silicon with a uniform subwavelength height,a nearly continuous phase coverage,a lightweight,flexible design,and low-heat dissipation.Thus,it may be mass produced by and integrated into existing semiconductor foundry designs.Our work opens important directions for emerging 3D recognition sensors,such as motion sensing,facial recognition,and other applications. | Zile Li Qi Dai Muhammad Q.Mehmood Guangwei Hu Boris Luk’yanchuk Jin Tao Chenglong Hao Inki Kim Heonyeong Jeong Guoxing Zheng Shaohua Yu Andrea Alù Junsuk Rho Cheng-Wei Qiu | 2018 | Light(Science & Applications)2018，7，1： | 6 |
| 12 | Orbital-scale Asian summer monsoon variations:Paradox and exploration显示文摘The Asian summer monsoon(ASM) is a vast climate system, whose variability is critical to the livelihoods of billions of people across the Asian continent. During the past half-century, much progress has been made in understanding variations on a wide range of timescales, yet several significant issues remain unresolved. Of note are two long-standing problems concerning orbital-scale variations of the ASM.(1) Chinese loess magnetic susceptibility records show a persistent glacial-interglacial dominated ~100 kyr(thousand years) periodicity, while the cave oxygen-isotope(δ18 O) records reveal periodicity in an almost pure precession band(~20 kyr periodicity)—the 'Chinese 100 kyr problem'.(2) ASM records from the Arabian Sea and other oceans surrounding the Asian continent show a significant lag of 8–10 kyr to Northern Hemisphere summer insolation(NHSI), whereas the Asian cave δ18 O records follow NHSI without a significant lag—a discrepancy termed the 'sea-land precession-phase paradox'. How can we reconcile these differences? Recent and more refined model simulations now provide spatial patterns of rainfall and wind across the precession cycle, revealing distinct regional divergences in the ASM domain, which can well explain a large portion of the disparities between the loess, marine, and cave proxy records. Overall, we also find that the loess, marine, and cave records are indeed complementary rather than incompatible, with each record preferentially describing a certain aspect of ASM dynamics. Our study provides new insight into the understanding of different hydroclimatic proxies and largely reconciles the 'Chinese 100 kyr problem' and 'sea-land precession-phase paradox'. | Hai CHENG Haiwei ZHANG Yanjun CAI Zhengguo SHI Liang YI Chenglong DENG Qingzhen HAO Youbing PENG Ashish SINHA Hanying LI Jingyao ZHAO Ye TIAN Jonathan BAKER Carlos PEREZ-MEJIAS | 2021 | Science China Earth Sciences2021，64，4： | 6 |
| 13 | Recent advances on organic-inorganic hybrid perovskite photodetectors with fast response显示文摘In the last decade,optoelectronic devices based on organic-inorganic hybrid perovskite(OIHP)materials,which have unique advantages of direct bandgap,large absorption coefficient,low density of defects,long charge carrier lifetime,diffusion length,and solution processability,have traveled with traditional inorganic semiconductor devices.The state-of-the-art OIHP photodetectors have contributed a comparable performance with Si and III-V compound semiconductor based photodetectors.Large amount of efforts have been focused on improving sensitivity,broadening detection spectra,enlarging linear dynamic range.However,few reports emphasized the important parameter of response speed.In this review,we summarize the progress and applications of OIHP photodetectors with fast response.Based on photovoltaic and photoconductive-type OIHP photodetectors,the working principle and key factors on determining response speed are systematically mentioned.Then,the research progress of response speed,which is composed of resistance-capacitance(RC)time constant and charge carrier transit time is discussed in detail.Subsequently,considering the intrinsic flexibility of perovskite materials,we briefly discuss the flexible photodetectors.Finally,an outlook and potential rules for designing fast-response OIHP photodetectors are further proposed. | Yan Zhao Chenglong Li Liang Shen | 2019 | InfoMat2019，1，2： | 6 |
| 14 | The use of fire at Zhoukoudian:evidence from magnetic susceptibility and color measurements显示文摘In order to provide direct evidence for the use of fire by humans at Locality 1,Zhoukoudian,we examine the burnt and unburnt sediments of newly excavated area in Layer 4 by detailed measurements of magnetic susceptibility,color,and diffuse reflectance spectrum.Results show that the magnetic susceptibility and redness of the burnt sediments are remarkably higher than those of other areas on the same level:up to*22 times for magnetic susceptibility and*3 times for redness of those of the adjacent unburnt sediments.Fine-grained(superparamagnetic/stable single-domain)magnetite and hematite grains make dominant contributions to the distinctly high values of magnetic susceptibility and redness in the burnt sediments.Diffuse reflectance spectroscopy results show that the burnt sediments contain more hematite than those of other areas and localities 2 and 3.High-temperature magnetic susceptibility measurements demonstrate that the burnt sediments have been heated above 700°C.Those changes in low-frequency magnetic susceptibility and redness are impossibly resulted from natural fires,thus most likely signaling the human activities of controlled use of fire.However,further work is needed to confirm whether or not these heat-affected sediments were produced in situ. | Yan Zhang Zhengtang Guo Chenglong Deng Shuangquan Zhang Haibin Wu Chunxia Zhang Junyi Ge Deai Zhao Qin Li Yang Song Rixiang Zhu | 2014 | Chinese Science Bulletin2014，59，10： | 6 |
| 15 | Intelligent metasurface imager and recognizer显示文摘There is an increasing need to remotely monitor people in daily life using radio-frequency probe signals.However,conventional systems can hardly be deployed in real-world settings since they typically require objects to either deliberately cooperate or carry a wireless active device or identification tag.To accomplish complicated successive tasks using a single device in real time,we propose the simultaneous use of a smart metasurface imager and recognizer,empowered by a network of artificial neural networks(ANNs)for adaptively controlling data flow.Here,three ANNs are employed in an integrated hierarchy,transforming measured microwave data into images of the whole human body,classifying specifically designated spots(hand and chest)within the whole image,and recognizing human hand signs instantly at a Wi-Fi frequency of 2.4 GHz.Instantaneous in situ full-scene imaging and adaptive recognition of hand signs and vital signs of multiple non-cooperative people were experimentally demonstrated.We also show that the proposed intelligent metasurface system works well even when it is passively excited by stray Wi-Fi signals that ubiquitously exist in our daily lives.The reported strategy could open up a new avenue for future smart cities,smart homes,human-device interaction interfaces,health monitoring,and safety screening free of visual privacy issues. | Lianlin Li Ya Shuang Qian Ma Haoyang Li Hanting Zhao Menglin Wei Che Liu Chenglong Hao Cheng-Wei Qiu Tie Jun Cui | 2019 | Light(Science & Applications)2019，8，1： | 5 |
| 16 | Terahertz wavefront shaping with multi-channel polarization conversion based on all-dielectric metasurface显示文摘Polarization manipulation of electromagnetic wave or polarization multiplexed beam shaping based on metasurfaces has been reported in various frequency bands.However,it is difficult to shape the beam with multi-channel polarization conversion in a single metasurface.Here,we propose a new method for terahertz wavefront shaping with multi-channel polarization conversion via all-silicon metasurface,which is based on the linear shape birefringence effect in spatially interleaved anisotropic meta-atoms.By superimposing the eigen-and non-eigen-polarization responses of the two kinds of meta-atoms,we demonstrate the possibility for high-efficiency evolution of several typical polarization states with two independent channels for linearly polarized waves.The measured polarization conversion efficiency is higher than 70%in the range of 0.9–1.3 THz,with a peak value of 89.2%at 1.1 THz.In addition,when more other polarization states are incident,combined with the integration of sub-arrays,we can get more channels for both polarization conversion and beam shaping.Simulated and experimental results verify the feasibility of this method.The proposed method provides a new idea for the design of terahertz multi-functional metadevices. | JIE LI CHENGLONG ZHENG JITAO LI GUOCUI WANG JINGYU LIU ZHEN YUE XUANRUO HAO YUE YANG FUYU LI TINGTING TANG YATING ZHANG YAN ZHANG JIANQUAN YAO | 2021 | Photonics Research2021，9，10： | 5 |
| 17 | Early Cretaceous Palynological Assemblages of the Shuangliao Fault Depression, Songliao Basin and their Geological Implications显示文摘The pollen and spores found in the Early Cretaceous strata of two cores from the Shuangliao Fault Depression were studied systematically, and two palynological assemblages have been recognized. Assemblage Ⅰ from the Yingcheng Formation is named Paleoconiferus-Pinuspollenites; the assemblage is characterized by an extremely high content of Paleoconifer pollen. Assemblage Ⅱ from Member 1 of the Denglouku Formation is named Cicatricosisporites-Cyathidites-Pinuspollenites; the assemblage is characterized by the abundant presence of Laevigati spores, but less Paleoconifer pollen. According to the palynological data and zircon U-Pb dating, the geological age of the Yingcheng Formation is thought to be Aptian-Albian, and that of the Denglouku Formation is thought to be Early Albian. On the basis of the composition of each assemblage, we can infer that during the depositional period of the Yingcheng Formation, the paleovegetation was mainly conifer forest, the paleoclimate was consistent with the temperate climate of today, and the paleoenvironment was humid feature. During the depositional period of Member 1 of the Denglouku Formation, the paleovegetation was mainly conifer forest and shrubs, the paleoclimate was consistent with the subtropical climate of today, and the paleoenvironment was humid. The results significantly improve our understanding of the stratigraphy in the Shuangliao Fault Depression, provide biostratigraphic evidence for the division and correlation of Early Cretaceous strata in the Shuangliao Fault Depression, and provide new data for analyzing paleovegetation and paleoclimate in the Songliao Basin. | WANG Chenglong ZHANG Meisheng LI Xiaobo WANG Yini | 2017 | Acta Geologica Sinica(English Edition)2017，91，6： | 5 |
| 18 | Seismic traveltime inversion of 3D velocity model with triangulated interfaces显示文摘Seismic traveltime tomographic inversion has played an important role in detecting the internal structure of the solid earth. We use a set of blocks to approximate geologically complex media that cannot be well described by layered models or cells. The geological body is described as an aggregate of arbitrarily shaped blocks,which are separated by triangulated interfaces. We can describe the media as homogenous or heterogeneous in each block. We define the velocities at the given rectangle grid points for each block,and the heterogeneous velocities in each block can be calculated by a linear interpolation algorithm. The parameters of the velocity grid positions are independent of the model parameterization,which is advantageous in the joint inversion of the velocities and the node depths of an interface. We implement a segmentally iterative ray tracer to calculate traveltimes in the 3D heterogeneous block models.The damped least squares method is employed in seismic traveltime inversion,which includes the partial derivatives of traveltime with respect to the depths of nodes in the triangulated interfaces and velocities defined in rectangular grids. The numerical tests indicate that the node depths of a triangulated interface and homogeneous velocity distributions can be well inverted in a stratified model. | Fei Li Tao Xu Minghui Zhang Zhenbo Wu Chenglong Wu Zhongjie Zhang Jiwen Teng | 2014 | Earthquake Science2014，27，2： | 5 |
| 19 | Concept of the solar ring mission:An overview显示文摘The concept of the Solar Ring mission was gradually formed from L5/L4 mission concept, and the proposal of its pre-phase study was funded by the National Natural Science Foundation of China in November 2018 and then by the Strategic Priority Program of Chinese Academy of Sciences in space sciences in May 2019. Solar Ring mission will be the first attempt to routinely monitor and study the Sun and inner heliosphere from a full 360-degree perspective in the ecliptic plane. The current preliminary design of the Solar Ring mission is to deploy six spacecraft, grouped in three pairs, on a sub-AU orbit around the Sun. The two spacecraft in each group are separated by about 30?and every two groups by about 120?. This configuration with necessary science payloads will allow us to establish three unprecedented capabilities:(1) determine the photospheric vector magnetic field with unambiguity,(2) provide 360-degree maps of the Sun and the inner heliosphere routinely, and(3) resolve the solar wind structures at multiple scales and multiple longitudes. With these capabilities, the Solar Ring mission aims to address the origin of solar cycle, the origin of solar eruptions, the origin of solar wind structures and the origin of severe space weather events. The successful accomplishment of the mission will advance our understanding of the star and the space environment that hold our life and enhance our capability of expanding the next new territory of human. | WANG YuMing JI HaiSheng WANG YaMin XIA LiDong SHEN ChengLong GUO JingNan ZHANG QuanHao HUANG ZhengHua LIU Kai LI XiaoLei LIU Rui WANG JingXiu WANG Shui | 2020 | Science China(Technological Sciences)2020，63，9： | 4 |
| 20 | Laser pattern-induced unidirectional lubricant flow for lubrication track replenishment显示文摘Effective oil replenishment to the lubrication track of a running bearing is crucial to its sustainable operation.Reliable practical solutions are rare despite numerous theoretical studies were conducted in the last few decades.This paper proposes the use of surface effect,wettability gradient,to achieve the goal.This method is simple and can be nicely implemented using femtosecond laser ablation.A periodic comb-tooth-shaped pattern with anisotropic wetting capability is devised and its effect on the anisotropic spreading behaviour of an oil droplet is studied.Results show that the comb-tooth-shaped pattern enables the rearrangement of oil distribution,thereby escalating oil replenishment to the lubrication track.The effect is due to the unbalanced interfacial force created by the surface pattern.The influence of the shape and the pitch of teeth,which are the two governing factors,on oil transport is also reported.The effects of the newly devised surface pattern on lubrication are experimentally evaluated under the conditions of limited lubricant supply.These results are promising,demonstrating the reduction in bearing friction and the increase in lubricating film thickness. | Chenglong LIU Feng GUO Patrick WONG Xinming LI | 2022 | Friction2022，10，8： | 4 |
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