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^(40)Ar-^(39)Ar and U-Pb ages of metadiorite from the East Kunlun Orogenic Belt: Evidence for Early-Paleozoic magmatic zone and excess argon in amphibole minerals

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Chinese Science Bulletin 2001年第4期46卷 330-333页

作者： CHEN Nengsong, SUN Min, ZHANG Kexin & ZHU YunhaiFaculty of Earth Sciences, China university of Geosciences, Wuhan 430074, China department of Earth Sciences, The university of hong kong, hong kong SAR, China Faculty of Earth Sciences China University of Geosciences Wuhan China department of Earth Sciences The University of Hong Kong Hong Kong SAR China

Single-grain zircon U-Pb and amphibole 40Ar-39Ar dating have been conducted on a deformed and metamorphosed diorite in the East Kunlun Orogenic Belt, which intruded into the middle Proterozoic Kuhai Group exposed in the south of Xiangride region, Dulan County, NW Qinghai Province. The zircon gives a concordant U-Pb age of (446.5±9.1) Ma. The amphibole yields Ar plateau age of (488.0±1.2. Ma and an isochronal age of (488.9±5.6) Ma. Age results of both stepwise released Ar and conventional K-Ar analysis are remarkably higher than that of zircon U-Pb, suggesting that the amphibole contains excess argon and the amphibole plateau age cannot be taken as the timing of metamorphism or deformation. The zircon age is interpreted to be crystallization age of the diorite pluton, which suggests that an Early-Paleozoic magmatic zone indeed existed in the East Kunlun Orogenic Belt stretching along the region south to the Golmud, Normuhong and Xiangride.

关键词： East Kunlun Orogenic Belt metadiorite geochronology excess argon.

FORCE REDUCTION OF FLOW AROUND A SINUSOIDAL WAVY CYLINDER

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Journal of Hydrodynamics 2009年第3期21卷 308-315页

作者： ZOU Lin LIN Yu-feng School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong China

A large eddy simulation of cross-flow around a sinusoidal wavy cylinder at Re = 3000 was performed and the load cell measurement was introduced for the validation test. The mean flow field and the near wake flow structures were presented and compared with those for a circular cylinder at the same Reynolds number. The mean drag coefficient for the wavy cylinder is smaller than that for a corresponding circular cylinder due to the formation of a longer wake vortex generated by the wavy cylinder. The fluctuating lift coefficient of the wavy cylinder is also greatly reduced. This kind of wavy surface leads to the formation of 3-D free shear layers which are more stable than purely 2.D free shear layers. Such free shear layers only roll up into mature vortices at further downstream position and significantly modify the near wake structures and the pressure distributions around the wavy cylinder. Moreover, the simulations in laminar flow condition were also performed to investigate the effect of Reynolds number on force reduction control.

关键词： wavy cylinder force reduction Large Eddy Simulation (LES) Reynolds number effect

GOODNESS-OF-FIT TEST ON TWO SAMPLES

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Systems Science and Mathematical Sciences 2000年第2期13卷 113-120页

作者： WANG Lixin YANG Zhenhai (department of Applied mathematics, Beijing Polytechnic {2., Beijing 10002., China) PANG Wankai (department of Applied mathematics, hong kong Polytechnic {2.) 北京工业大学应用数学系北京 100002 北京工业大学应用数学系北京香港理工大学香港

In this paper, a new statistics for testing two samples coming from the same population is derived from a simple linear model with an artificial parameter. Its limit distribution is a chi-squared distribution with 2.degrees of freedom under null hypothesis and the limit distribution is a noncentral chi-squared distribution with 2.degrees of freedom under certain sequence of alternative hypothesis. Finally, we make power comparison with other tests on two samples, especially, with Smirnov statistics.

关键词： Goodness-of-fit test simple linear model artificial parameter two-sample problem.

Temperature variation in Guangdong Province, China

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Journal of Geographical Sciences 1999年第2期9卷 95-104页

作者： YAN Yuk Yee (department of Geography,hong kong Baptist {2. Kowloon Tong. hong kong)

Temperature variation in Guangdong Province of China between 1956 and 1990 was investigaed Simple linear trend analysis was ed to examine the temporal trend and the climatic departure index (CDI) was employed to study the regional variability Warming trends in maximum,minimum and average temperatures discovered for both winter and summer For annual temperatures a cooling trend in maximum temperature was observed. The mostrecent decade was found to be warmer than the previous ones. A detailed esamination of Shenzhen revealed that warming trebds were more prominent than regional average trend,indicating that urbanization and industrialization might influence the average temperature trends. The results of the CDI analysis showed that temperatures had not become mere variable.

关键词： temperature variation climatic indexl index Guangdong

High-Quality van der Waals Epitaxial CsPbBr3 Film Grown on Monolayer Graphene Covered TiO2.for High-Performance Solar Cells

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Energy & Environmental Materials 2024年第4期7卷 239-246页

作者： Zhaorui Wen Chao Liang Shengwen Li Gang Wang Bingchen He Hao Gu Junpeng Xie Hui Pan Zhenhuang Su Xingyu Gao Guo hong Shi Chen Institute of Applied Physics and Materials Engineering University of Macau MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter State Key Laboratory for Mechanical Behavior of Materials School of Physics Xi'an Jiaotong University Shanghai Institute of Applied Physics Chinese Academy of Sciences department of Materials Science and Engineering & Center of Super-Diamond and Advanced Films City University of Hong Kong

Two-dimensional materials have been widely used to tune the growth and energy-level alignment of ***,their incomplete passivation and chaotic usage amounts are not conducive to the preparation of highquality perovskite ***,we succeeded in obtaining higher-quality CsPbBr3films by introducing large-area monolayer graphene as a stable physical overlay on top of TiO2.ubstrates.

关键词： all-inorganic perovskite solar cells buried interface modification monolayer graphene van der Waals epitaxial growth

Atmospheric oxidation capacity and O_(3) formation in a coastal city of southeast China:Results from simulation based on four-season observation

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Journal of Environmental Sciences 2024年第2期136卷 68-80页

作者： Gaojie Chen Taotao Liu Jinsheng Chen Lingling Xu Baoye Hu Chen Yang Xiaolong Fan Mengren Li Youwei hong Xiaoting Ji Jinfang Chen Fuwang Zhang Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China university of Chinese Academy of Sciences Beijing 100049China Minnan Normal university Zhangzhou 363000China College of Harbour and Coastal Engineering Jimei UniversityXiamen 361021China Environmental Monitoring Center of Fujian Fuzhou 350013China

The pollution of atmospheric ozone in China shows an obvious upward trend in the past ***,the studies on the atmospheric oxidation capacity and O_(3)formation in four seasons in the southeastern coastal region of China with the rapid urbanization remain ***,a four-season field observation was carried out in a coastal city of southeast China,using an observation-based model combining with the Master Chemical Mechanism,to explore the atmospheric oxidation capacity(AOC),radical chemistry,O_(3)formation pathways and *** results showed that the average net O_(3)production rate(14.55 ppbv/hr)in summer was the strongest,but the average O_(3)concentrations in autumn was *** AOC and ROx levels presented an obvious seasonal pattern with the maximum value in summer,while the OH reactivity in winter was the highest with an average value of 2..75 sec^(-1).The OH reactivity was dominated by oxygenated VOCs(OVOCs)(30.6%-42.8%),CO(2..2.-2..8%),NO_(2.(13.6%-2..0%),and alkenes(8.4%-12.5%)in different *** photolysis dominated OH primary source on daytime in winter,while in other seasons,HONO photolysis in the morning and ozone photolysis in the afternoon contributed *** analysis indicated that O_(3)production was controlled by VOCs in spring,autumn and winter,but a VOC-limited and NOx-limited regime in summer,and alkene and aromatic species were the major controlling factors to O_(3)***,the study characterized the atmospheric oxidation capacity and elucidated the controlling factors for O_(3)production in the coastal area with the rapid urbanization in China.

关键词： Atmospheric oxidation capacity Radical chemistry Ozone production Sensitivity analysis

Development of Multi-Agent-Based Indoor 3D Reconstruction

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Computers, Materials and Continua 2024年第1期81卷 161-181页

作者： Cheng H.C. hong F.Z. Hussain B. Wang Y. Yue C.P. Optical Wireless Lab Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology Hong Kong

Large-scale indoor 3D reconstruction with multiple robots faces challenges in core enabling technologies. This work contributes to a framework addressing localization, coordination, and vision processing for multi-agent reconstruction. A system architecture fusing visible light positioning, multi-agent path finding via reinforcement learning, and 360° camera techniques for 3D reconstruction is proposed. Our visible light positioning algorithm leverages existing lighting for centimeter-level localization without additional infrastructure. Meanwhile, a decentralized reinforcement learning approach is developed to solve the multi-agent path finding problem, with communications among agents optimized. Our 3D reconstruction pipeline utilizes equirectangular projection from 360° cameras to facilitate depth-independent reconstruction from posed monocular images using neural networks. Experimental validation demonstrates centimeter-level indoor navigation and 3D scene reconstruction capabilities of our framework. The challenges and limitations stemming from the above enabling technologies are discussed at the end of each corresponding section. In summary, this research advances fundamental techniques for multi-robot indoor 3D modeling, contributing to automated, data-driven applications through coordinated robot navigation, perception, and modeling. © 2.2. The Authors. Published by Tech Science Press.

关键词： 3D reconstruction multi-agent path finding Multi-agent system multi-robot human collaboration reinforcement learning visible light communication visible light positioning

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铁代谢蛋白在肾脏的表达与功能

生物化学与生物物理进展 2011年第2期38卷 113-118页

作者：蔺艳钱忠明柯亚香港理工大学应用生物化学系香港中文大学医学院生物医学学院

最近的研究证实,肾小管细胞具有能力表达包括转铁蛋白受体1(transferrin receptor-1,TfR1)、二价金属离子转运蛋白1(divalent metal transporter-1,DMT1)、膜铁转运蛋白1(ferroportin-1,FPN1)、铁调节蛋白(iron regulatory protein,IRP)和铁调素(hepcidin,Hepc)在内的几乎所有铁代谢蛋白.这些蛋白质的存在以及相关研究显示肾脏可能具有排出多余铁的功能,因此对体铁平衡起有十分重要的作用.

关键词：肾小管铁代谢蛋白排铁铁平衡

Enhancement of second-order harmonic generation in polarized BaTiO_3 thin films embedded with Ag nanoparticles

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Chinese Science Bulletin 1997年第15期42卷 1319-1320页

作者： ZHOU Ji, LI Longtu, GUI Zhilun, ZHANG Xiaowen, K. M. Moulding and D. J. Barber1 department of Materials Science and Engineering, Tsinghua university, Beijing 100084, China {2. of Physics, The hong kong university of Science and Technology, hong kong, China department of Materials Science and Engineering Tsinghua University Beijing China department of Physics The Hong Kong University of Science and Technology Hong Kong China

RECENTLY, much attention has been paid to optical properties of ferroelectric thin films. Be-

关键词： Ba Ag Enhancement of second-order harmonic generation in polarized BaTiO3 thin films embedded with Ag nanoparticles