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| 1 | Design, Preparation and Properties of Carbon Fiber Reinforced Ultra-High Temperature Ceramic Composites for Aerospace Applications: A Review显示文摘Carbon fiber reinforced ultra-high temperature ceramic(UHTC) composites, consisting of carbon fibers embedded in a UHTC-matrix or a C–SiC–UHTC-matrix, are deemed as the most viable class of materials that can overcome the poor fracture toughness and thermal shock resistance of monolithic UHTC materials, and also improve the oxidation resistance and ablation resistance of C/C and C/SiC composites at ultra-high temperatures. In this review, we summarize the different processing routes of the composites based on the UHTC introducing methods, including chemical vapor infiltration/deposition(CVI/D),precursor infiltration and pyrolysis(PIP), reactive melt infiltration(RMI), slurry infiltration(SI), in-situ reaction, hot pressing(HP), etc; and the advantages and drawbacks of each method are briefly discussed. The carbon fiber reinforced UHTC composites can be highly tailorable materials in terms of fiber,interface, and matrix. From the perspective of service environmental applications for engine propulsions and hypersonic vehicles, the material designs(mainly focusing on the composition, quantity, structure of matrix, as well as the architecture of carbon fibers, UHTCs and pores), their relevant processing routes and properties(emphasizing on the mechanical and ablation properties) are discussed in this paper. In addition, we propose a material architecture to realize the multi-function through changing the distribution of carbon fibers, UHTCs and pores, which will be an important issue for future development of carbon fiber reinforced UHTC composites. | Sufang Tang Chenglong Hu | 2017 | Journal of Materials Science & Technology2017，33，2： | 51 |
| 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 | 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 |
| 4 | Genome-Wide Association Studies of Image Traits Reveal Genetic Architecture of Drought Resistance in Rice显示文摘理解植物怎么对干旱作出回应能有益于繁殖的干旱抵抗(医生) 。用一台非破坏性的 phenotyping 设备,为 507 米饭就职的 51 个基于图象的特点(i 特点) 被提取。这些 i 特点能被用来监视干旱回答 ? 并且高评估医生可遗传性和这些特点的大变化在自然人口在干旱应力下面被观察。染色体宽的协会研究(GWAS )?i 特点和传统的医生特点识别了 470 协会 loci,某包含知道医生相关的基因。这 470 loci, 443 loci (94%) 用 i 特点被识别, 437 loci (93%) 与以前报导的医生相关的量的特点 loci,和 313 loci (66.6%)co 局部性被 GWAS reproducibly 在不同的年里识别。协会网络,基于 GWAS 建立了结果,揭示中心 i 特点和中心 loci。这表明把的可行性和必要性复杂医生特点进可继承、简单的 i 特点。作为原则的证明,我们说明了这条综合途径的力量以前识别 unreported 医生相关的基因。OsPP15 与中心 i 特点被联系,并且它在医生的角色被基因转变实验证实。而且, i 特点能被用于医生连接分析,并且 69 个 i 特点地点协会被 recombinant 的 GWAS 和连接分析识别生来的线人口。最后,我们证实了 i 特点的关联在这个领域里搀。我们的学习为医生为原因的基因的基因解剖和发现提供一条有希望的新奇途径。 | Zilong Guo Wanneng Yang Yu Chang Xiaosong Ma Haifu Tu Fang Xiong Ni Jiang Hui Feng Chenglong Huang Peng Yang Hu Zhao Guoxing Chen Hongyan Liu Lijun Luo Honghong Hu Qian Liu Lizhong Xiong | 2018 | Molecular Plant2018，11，6： | 21 |
| 5 | Environmental magnetic studies of lacustrine sediments显示文摘In recent decades, environmental magnetism has become an important method for studying past global climatic and environmental changes. For an environmental magnetic study, it is important to understand the magnetic properties of various magnetic minerals in lacustrine sediments and the processes involved in the formation, transport, and preservation of these magnetic minerals. The magnetic response of lacustrine sediments to climatic change may vary widely from lake to lake. To reconstruct the processes contributing to paleoclimatic and paleoenvironmental change, it is, therefore, necessary to derive a complete understanding of the potential origin of the magnetic signal observed. | HU Shouyun, DENG Chenglong, E. Appel & K. L. VerosubNanjing Institute of Geography and Limnology, Nanjing 210008, China Institute of Geology and Geophysics, Beijing 100101, China Institut fur Geologic, Universitat Tubingen, 72076 Tubingen, Germany Departm | 2002 | Chinese Science Bulletin2002，47，7： | 18 |
| 6 | Determination of rice panicle numbers during heading by multi-angle imaging显示文摘Plant phenomics has the potential to accelerate progress in understanding gene functions and environmental responses. Progress has been made in automating high-throughput plant phenotyping. However, few studies have investigated automated rice panicle counting. This paper describes a novel method for automatically and nonintrusively determining rice panicle numbers during the full heading stage by analyzing color images of rice plants taken from multiple angles. Pot-grown rice plants were transferred via an industrial conveyer to an imaging chamber. Color images from different angles were automatically acquired as a turntable rotated the plant. The images were then analyzed and the panicle number of each plant was determined. The image analysis pipeline consisted of extracting the i2 plane from the original color image, segmenting the image, discriminating the panicles from the rest of the plant using an artificial neural network, and calculating the panicle number in the current image. The panicle number of the plant was taken as the maximum of the panicle numbers extracted from all 12 multi-angle images. A total of 105 rice plants during the full heading stage were examined to test the performance of the method. The mean absolute error of the manual and automatic count was 0.5, with 95.3% of the plants yielding absolute errors within ± 1. The method will be useful for evaluating rice panicles and will serve as an important supplementary method for high-throughput rice phenotyping. | Lingfeng Duan Chenglong Huang Guoxing Chen Lizhong Xiong Qian Liu Wanneng Yang | 2015 | The Crop Journal2015，3，3： | 18 |
| 7 | A Multiscale Understanding of the Thermodynamic and Kinetic Mechanisms of Laser Additive Manufacturing显示文摘 | Dongdong Gu Chenglong Ma Mujian Xia Donghua Dai Qimin Shi | 2017 | Engineering2017，3，5： | 15 |
| 8 | A newly discovered Gigantopithecus fauna from Sanhe Cave, Chongzuo, Guangxi, South China显示文摘Among the most important faunas in the Late Cenozoic, the Gigantopithecus faunas have received a good deal of attention. The Gigantopithecus fauna recently discovered in Sanhe Cave consists of more than 80 mammal species, including cf. Hominidae, Pongo sp., Hylobates sp., Sinomastodon yangzien-sis, Stegodon preorientalis, Cervavitus fenqii, Dicoryphochoerus ultimus and Sus xiaozhu. It is the southernmost Gigantopithecus fauna found so far in China. Its geological age is estimated to be Early Pleistocene based on the fauna and stratigraphic correlation. The significant increase in the estimated body sizes of Ailuropoda, Gigantopithecus and Tapirus shows that the Sanhe fauna is middle Early Pleistocene, later than those from Wushan and Liucheng (early Early Pleistocene). Paleomagnetic dating of the fossil-bearing strata in Sanhe Cave gives an age of approximately 1.2 Ma. The fauna is characterized by tropical-subtropical forest types, including Pongo sp., Tupaia sp., Ia sp., Typhlomys intermedius, etc., and it lacks Palaearctic types. It is a typical tropical forest fauna, suggesting an en-vironment with a lush forest and a warm and humid climate. The discovery of the Sanhe Gigantopith-ecus fauna is significant for establishing the chronological stages of the Gigantopithecus faunas in China, and for discussing their origin, evolution and dynamics. | JIN ChangZhu QIN DaGong PAN WenShi TANG ZhiLu LIU JinYi WANG Yuan DENG ChengLong ZHANG YingQi DONG Wei TONG HaoWen | 2009 | Chinese Science Bulletin2009，54，5： | 14 |
| 9 | Performance analysis of ghost imaging lidar in background light environment显示文摘The effect of background light on the imaging quality of three typical ghost imaging(GI) lidar systems(namely narrow pulsed GI lidar, heterodyne GI lidar, and pulse-compression GI lidar via coherent detection) is investigated. By computing the signal-to-noise ratio(SNR) of fluctuation-correlation GI, our analytical results, which are backed up by numerical simulations, demonstrate that pulse-compression GI lidar via coherent detection has the strongest capacity against background light, whereas the reconstruction quality of narrow pulsed GI lidar is the most vulnerable to background light. The relationship between the peak SNR of the reconstruction image andσ(namely, the signal power to background power ratio) for the three GI lidar systems is also presented, and theresults accord with the curve of SNR-σ. | CHENJIN DENG LONG PAN CHENGLONG WANG XIN GAO WENLIN GONG SHENSHENG HAN | 2017 | Photonics Research2017，5，5： | 13 |
| 10 | 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 |
| 11 | Astronomical tuning and magnetostratigraphy of Neogene biogenic reefs in Xisha Islands, South China Sea显示文摘Biogenic reefs are one of two major depositional types in the South China Sea, and are constructed by coral, algae and bryozoa. The West Pacific is a major area of biogenic reef development and plays a critical role in the global carbon cycle. However, the lack of geochronological studies in previous works inhibits our understanding of their contributions. Herein, we conduct a cyclostratigraphic and magnetostratigraphic study on Neogene biogenic reefs using the XK–1 core that was drilled at the Shidao Island,Xisha(Paracel) Islands. The main findings of this study are:(1) the establishment of reliable magentostratigraphy for Ledong, Huangliu, Meishan and Sanya Formations;(2) the magnetic susceptibility variation can be inferred as growth index and tuned to the 405–ka long eccentricity cycle;(3) the astronomical geochronology suggests that the bottom ages for Ledong, Yinggehai, Huangliu, Meishan,and Sanya Formations are 2.2 Ma, 5.7 Ma, 10.4 Ma, 16.6 Ma, and 24.3 Ma, respectively; and (4) Earth's eccentricity and obliquity played predominant roles in biogenic reef establishment on orbital to tectonic timescales. Thus, the reported geochronology offers an opportunity to test the contributions of various factors and hypothesize their roles in the global carbon cycle in future. | Liang Yi Zhimin Jian Xinyu Liu Youhua Zhu Daojun Zhang Zhenfeng Wang Chenglong Deng | 2018 | Science Bulletin2018，63，9： | 12 |
| 12 | The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China显示文摘Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in Shenyang. | Zhuobiao Ma Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue Di Zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu | 2019 | Journal of Environmental Sciences2019，31，5： | 12 |
| 13 | Seasonal and diurnal variations of atmospheric peroxyacetyl nitrate, peroxypropionyl nitrate, and carbon tetrachloride in Beijing显示文摘Atmospheric peroxyacetyl nitrate(PAN), peroxypropionyl nitrate(PPN), and carbon tetrachloride(CCl4) were measured from September 2010 to August 2011 in Beijing. PAN exhibited low values from mid-autumn to early spring(October to March) with monthly average concentrations ranging from 0.28 to 0.73 ppbV, and increased from early spring to summer(March to August), ranging from 1.37–3.79 ppbV. The monthly variation of PPN was similar to PAN, with low values(below detection limit to 0.18 ppbV) from mid-autumn to early spring, and a monthly maximum in September(1.14 ppbV). The monthly variation of CCl4was tightly related to the variation of temperature, exhibiting a minimum in winter(69.3 pptV) and a maximum of 180.6 pptV in summer. Due to weak solar intensity and short duration, PAN and O3showed no distinct diurnal patterns from morning to night during winter, whereas for other seasons, they both exhibited maximal values in the late afternoon(ca. 15:00 to 16:00 local time) and minimal values during early morning and midnight. Good linear correlations between PAN and PPN were found in autumn(R = 0.91), spring(R = 0.94), and summer(R = 0.81), with slopes of 0.130, 0.222, and 0.133, respectively, suggesting that anthropogenic hydrocarbons dominated the photochemical formation of PANs in Beijing. Positive correlation between PAN and O3 in summer with the low slopes( O3 / PAN) ranging from 9.92 to 18.0 indicated serious air pollution in Beijing, and strong negative correlation in winter reflected strong O3consumption by NO titration and less thermal decompositin of PAN. | Gen Zhang Yujing Mu Junfeng Liu Chenglong Zhang Yuanyuan Zhang Yujie Zhang Hongxing Zhang | 2014 | Journal of Environmental Sciences2014，26，1： | 11 |
| 14 | 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 |
| 15 | Generation of super-resolved optical needle and multifocal array using graphene oxide metalenses显示文摘Ultrathin flat metalenses have emerged as promising alternatives to conventional diffractive lenses,offering new possibilities for myriads of miniaturization and interfacial applications.Graphene-based materials can achieve both phase and amplitude modulations simultaneously at a single position due to the modification of the complex refractive index and thickness by laser conversion from graphene oxide into graphene like materials.In this work,we develop graphene oxide metalenses to precisely control phase and amplitude modulations and to achieve a holistic and systematic lens design based on a graphene-based material system.We experimentally validate our strategies via demonstrations of two graphene oxide metalenses:one with an ultra-long(~16λ)optical needle,and the other with axial multifocal spots,at the wavelength of 632.8 nm with a 200 nm thin film.Our proposed graphene oxide metalenses unfold unprecedented opportunities for accurately designing graphene-based ultrathin integratable devices for broad applications. | Hongtao Wang Chenglong Hao Han Lin Yongtian Wang Tian Lan Chengwei Qiu Baohua Jia | 2021 | Opto-Electronic Advances2021，4，2： | 10 |
| 16 | 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 |
| 17 | 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 |
| 18 | Experimental results and analysis of sparse microwave imaging from spaceborne radar raw data显示文摘Sparse microwave imaging is a novel radar framework aiming to bring revolutions to the microwave imaging according to the theory of sparse signal processing.As compressive sensing(CS)is introduced to synthetic aperture radar(SAR)imaging in recent years,the current SAR sparse imaging methods have shown their advantages over the traditional matched filtering methods.However,the requirement for these methods to process the compressed range data results in the increase of the hardware complexity.So the SAR sparse imaging method that directly uses the raw data is needed.This paper describes the method of SAR sparse imaging with raw data directly,presents the analysis of the signal-to-noise ratio(SNR)in the echo signal by combining the traditional radar equation with the compressive sensing theory,and provides the tests on 2-D simulated SAR data.The simulation results demonstrate the validity of the SNR analysis,and the good performance of the proposed method while a large percentage of the raw data is dropped.An experiment with RadarSat-1 raw data is also carried out to show the feasibility of processing the real SAR data via the method proposed in this paper.Our method is helpful for designing new SAR systems. | JIANG ChengLong ZHANG BingChen ZHANG Zhe HONG Wen WU YiRong | 2012 | Science China(Information Sciences)2012，55，8： | 9 |
| 19 | 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 |
| 20 | Domain structure and defects of highly ordered Bi_4Si_3O_(12) micro-crystals显示文摘Highly ordered Bi4Si3O12 micro-crystals were prepared at normal atmosphere. Phase identification of the prepared crystals was accomplished by X-ray diffractometer (XRD). Domain structure and defects were characterized by environmental scanning electron microscopy (ESEM). XRD shows that the obtained micro-crystals are of eulytite structure with chemical formulation of Bi4Si3O12. A highly ordered growth pattern is confirmed due to the faster growth of the {124} faces than that of the {204} faces by ESEM. The growing process of the domain structure is of pollen parent and filial generation pattern. The filial generations of Bi4Si3O12 crystals are generated from the pollen parent. Cracks generate from the defect areas and propagate along the {124} faces due to their lower binding energy under a proper temperature gradient, contributing to the total transcrystalline fracture. It is confirmed that the generation and development of the voids in the crystal grains can be developed when unmatched dimensions of the two opposite faces are formed. And the development of the voids is dependent on the dimensions and orientations of the two opposite faces. | TIAN QingQuan, WANG XiuFeng, YU ChengLong, JIANG HongTao, ZHANG ZhengGuang, WANG Yan & LIN SheBao School of Materials Science and Engineering, Shaanxi University of Science & Technology, Xi’an 710021, China | 2009 | Science China(Technological Sciences)2009，52，8： | 8 |
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