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Progress in Natural Science:Materials International 2014年第2期24卷 109-115页

作者： Yu Tan yanguo wang Science College Hunan Agricultural University Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences

The effect of bias polarity on the electrical breakdown behavior of the single ZnSe nanowire(NW) in the metal–semiconductor–metal(M–S–M)nanostructure under high current density and high bias conditions has been studied in the present paper. The experimental results show that the failure of the ZnSe NW in M–S–M nanostructure was sensitive to bias polarity since the NW commonly collapsed at the negatively biased Au metal electrode due to high Joule heat produced in NW at the reversely biased Schottky barrier. Thus, the electrical breakdown behavior of the ZnSe NW was highly dominated by the cathode-controlled mode due to the high resistance of the depletion region of ZnSe NW at the reversely biased Schottky contact.

关键词： Semiconductor nanowire Electrical failure Schottky barrier Bias polarity In situ TEM

The Nanoscale Density Gradient as a Structural Stabilizer for Glass Formation

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Engineering 2023年第10期29卷 120-129页

作者： Shaoxiong Zhou Bangshao Dong yanguo wang Jingyu Qin Weihua wang China Iron and Steel Research Institute Group Beijing 100081China Institute of Advanced Materials North China Electric Power UniversityBeijing 102206China Jiangsu JITRI Advanced Energy and Materials Research Institute Changzhou 213032China Beijing National Laboratory of Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Key Laboratory for Liquid–Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China

The rapid cooling of a metallic liquid(ML)results in short-range order(SRO)among the atomic arrangements and a disordered structure in the resulting metallic glass(MG).These phenomena cause various possible features in the microscopic structure of the MG,presenting a puzzle about the nature of the MGs’microscopic structure beyond *** this study,the nanoscale density gradient(NDG)originating from a sequential arrangement of clusters with different atomic packing densities(APDs),representing the medium-range structural heterogeneity in Zr_(60)Cu_(30)Al_(10)MG,was characterized using electron tomography(ET)combined with image simulations based on structure *** coarse polyhedrons with distinct facets identified in the three-dimensional images coincide with icosahedron-like clusters and represent the spatial positions of clusters with high *** of the different clusters according to descending APD order in the glass-forming process are responsible for the NDG that stabilizes both the supercooled ML and the amorphous states and acts as a hidden rule in the transition from ML to MG.

关键词： Rapid cooling Amorphous solid Density gradient Electron tomography Atomic clusters

Morphological characterization of selectively overgrown GaN via lateral epitaxy

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电子显微学报 2001年第4期20卷 292-293页

作者： wang yanguo 中科院物理所北京电子显微镜开放实验室北京 100080

IntroductionGaN has attracted a lot of research attention because it has lower Ohmic contact resistance, large electron saturation velocity and a large breakdown field, combined with excellent thermal conductivity and stability, making it an excellent material for high-temperature, high-power and high-brightness optoelectronic devices such as field effect transistors (FET), junction (FET), bipolar transistors and photodiodes[1]. Since threading dislocations resulting from large lattice mismatach and the difference between thermal expansion coefficients of epitaxial GaN and substrate severely degrade the optical and electric qualities of the GaN layer, high quality GaN is indeed required for manufacture of high performance optical device[2]. Characterization of the microstructures of selectively lateral overgrowth of epitaxial GaN using SEM is presented in this work with focus on fully understanding evolution of the morphology and dislocation distribution that occurs in the different growth situations in order for establishment of procession-microstructure-properties interrelations.

关键词： GaN Morphological characterization of selectively overgrown GaN via lateral epitaxy

Effect of Electron Beam Orientation on Exit Wave Function via Simulation of Electron Dynamic Diffraction

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Journal of Materials Science & Technology 2007年第5期23卷 713-716页

作者： yanguo wang Hongrong LIU Canying CAI Qibing YANG Micro-Nano Technologies Research Center Hunan University Changsha 410082 China Institute of Modern Physics Xiangtan University Xiangtan 411105 China Institute of Physics Chinese Academy of Sciences P.O. Box 603 Beijing 100080 China

Based on the electron dynamic diffraction, phase shift of the exit wave function vs misorientation of the incident electron beam from the exact zone axis has been calculated for the [001] oriented copper. The result shows that the peak of phase shift is the maximum at the atom position as the electron beam along the exact [001] zone axis, and the peak value of phase shift decreases as increases of the misorientation. At small misorientation, i.e. less than 5 degree, change of the phase shift is minimal. The peak value of phase shift decreases significantly when the incident beam deviates form the zone axis over 10 degree and the exit wave has a planar configuration as the misoriention angle arrives -17 degree. The effect of this phase shift characteristics on the information extracted from the hologram has also been considered.

关键词： Electron dynamic diffraction Phase shift Exit wave function Misorientation

Community structure of zooplankton in the Lembeh Strait,Bitung, and Wori Beach, Manado, North Sulawesi,Indonesia

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Acta Oceanologica Sinica 2018年第12期37卷 28-34页

作者： THOHA Hikmah FITRIYA Nurul SIANTURI Oksto Ridho wang yanguo Research Center for Oceanography Indonesian Institute of Sciences Third Institution of Oceanography Ministry of Natural Resources

The community structure of zooplankton has been conducted in the Lembeh Strait in Bitung and Wori Beach in Manado, North Sulawesi in October 2015. Sampling of this research was conducted in 22 sampling sites along the strait. Zooplankton samples were collected from 22 stations, by NORPAC 300 μm net that was vertically hauled from maximum 10 m depth up to the surface water. The samples were poured into the bottle with formalin of 4%as preservative. The results showed that there were 43 taxa of zooplankton. The abundance of zooplankton was between 21.216–4 193.776 ind./m;. The dominant taxa were copepod, especially Calanoida. The composition of zooplankton was relatively similar in all stations. We showed the abundance, dominance, composition and distribution of zooplankton at this research. More extensive studies concerning zooplankton is required to understand zooplankton biodiversity as a whole especially on the geographical and spatial distribution to describe population and community dynamic in the Lembeh Strait and Wori Beach.

关键词： Lembeh Strait Wori Beach zooplankton copepoda calanoida

Two new species of medusae(Cnidaria) from the coastal waters of the northern Beibu Gulf

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Acta Oceanologica Sinica 2020年第12期39卷 82-89页

作者： Xiaoyin Chen Yanyan Yang yanguo wang Zhenzu Xu Mao Lin Chunguang wang Third Institute of Oceanography Ministry of Nature ResourcesXiamen 361005China University of Chinese Academy of Sciences Beijing 100049China Collaborative Innovation Center of Deep Sea Biology Zhejiang UniversityHangzhou 310012China College of Ocean and Earth Science Xiamen UniversityXiamen 361005China

Medusae in 116 samples collected from the coastal waters of the northern Beibu Gulf during four seasonal oceanographic cruises from October 2017 to August 2018 were *** total,34 species were *** of the species are new to science,Proboscidactyla pentacanalis Xu,Chen&Yang *** Helgicirrha apapillata Xu,Chen&wang ***.,and three species are newly recorded in the Beibu Gulf,i.e.,Hydractinia vacuolata Xu&Huang,2006,Proboscidactyla flavicirrata Brandnt,1834 and Phialella macrogona Xu,Huang&wang,*** of the species were deposited at the Third Institute of Oceanography,Ministry of Natural Resources.

关键词： medusae Cnidaria new species coastal waters northern Beibu Gulf

Regional disparities of phytoplankton in relation to environmental factors in the western Arctic Ocean during summer of 2010

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Acta Oceanologica Sinica 2018年第4期37卷 109-120页

作者： LIN Gengming wang yanguo CHEN Yanghang YE Youyin wang Yu YANG Qingliang Third Institute of Oceanography State Oceanic Administration

Global warming has caused Arctic sea ice to rapidly retreat,which is affecting phytoplankton,the primary producers at the base of the food chain,as well as the entire ***,few studies with large spatial scales related to the Arctic Basin at high latitude have been *** study aimed to investigate the relationship between changes in phytoplankton community structure and ice *** surface and 41 vertically stratified water samples from the western Arctic Ocean（67.0°–88°26′N,152°–178°54′W） were collected by the Chinese icebreaker R/V Xuelong from July 20 to August 30,2010 during China＇s fourth Arctic *** these samples,the species composition,spatial distribution,and regional disparities of phytoplankton during different stages of ice melt were assessed.A total of 157 phytoplankton taxa（〉5 μm） belonging to 69 genera were identified in the study *** most abundant species were Navicula pelagica and Thalassiosira nordenskioeldii,accounting for 31.23% and 14.12% of the total phytoplankton abundance,*** average abundance during the departure trip and the return trip were 797.07×10~2 cells/L and 84.94×10~2 cells/L,*** highest abundance was observed at Sta.R09 in the north of Herald Shoal,where Navicula pelagica was the dominant species accounting for 59.42% of the *** vertical distribution of phytoplankton abundance displayed regional differences,and the maximum abundances were confined to the lower layers of the euphotic zone near the layers of the halocline,thermocline,and *** species abundance of phytoplankton decreased from the low-latitude shelf to the high-latitude basin on both the departure and return *** phytoplankton community structure in the shallow continental shelf changed markedly during different stages of ice melt,and there was shift in dominant species from centric to pennate *** of canonical correspondence analysis（CCA） showed that there were

关键词： phytoplankton regional disparity species composition spatial distribution western Arctic Ocean

Hydromedusae from the Arctic in 2010 during the 4th Chinese National Arctic Research Expedition(CHINARE 4)

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Acta Oceanologica Sinica 2014年第6期33卷 95-102页

作者： wang Chunguang HUANG Jiaqi XIANG Peng wang yanguo XU Zhenzu GUO Donghui LIN Mao Third Institute of Oceanography State Oceanic Administration College of Oceanography and Environmental Science Xiamen University State Key Laboratory of Marine Environmental Science Xiamen University Collaborative Innovation Center of Deep Sea Biology

Fifty-seven stations （48 grid stations and nine stratified stations） were sampled across the study region （67.000°-88.394°N, 152.500°-178.643°W） during the 4th Chinese National Arctic Research Expedition （CHI- NARE 4） from July to August 2010 by the icebreaker R/VXuelong. A total of 24 species of Hydromedusae were identified from 130 zooplankton samples, of which seven species belonged to Automedusa, eight species to Anthomedusae, four species to Leptomedudae, and three species to Siphonophora. Catablema multicir- ratum Kishinouye, 1910, Bougainvillia bitentaculata Uchida, 1925, and Euphysajaponica （Maas, 1909） were recorded for the first time in the Arctic sea. In the present paper, 18 species of Hydromedusae were described and illustrated, of which three species were described for the first time in the Arctic sea, and 15 species were described for the first time in China.

关键词： Arctic Hydromedusae taxonomy

Controlling charges distribution at the surface of a single GaN nanowire by in-situ strain

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Progress in Natural Science:Materials International 2017年第4期27卷 430-434页

作者： Xiao Chen yanguo wang Jikang Jian Lin Gu Zhihua Zhang Liaoning Key Materials Laboratory for Railway Dalian Jiaotong University Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences School of physics science and technology Xinjiang University Collaborative Innovation Center of Quantum Matter

Effect of the strain on the charge distribution at the surface of a GaN semiconductor nanowire(NW) has been investigated inside transmission electron microscope(TEM) by in-situ off-axis electron holography. The outer and inner surfaces of the NW bent axially under compression of two Au electrodes were differently strained,resulting in difference of their Fermi levels. Consequently, the free electrons flow from the high Fermi level to the low level until the two Fermi levels aligned in a line. The potential distributions induced by charge redistribution in the two vacuum sides of the bent NW were examined respectively, and the opposite nature of the bounded charges on the outer and inner surfaces of the bent NW was identified. The results provide experimental evidence that the charge distribution at the surfaces of a single GaN NW can be controlled by different strains created along the NW.

关键词： Nanowire Strain Charge distribution Electron holography TEM

Preparation and Crystallization of Carbon Nanotube/maleic Anhydride-grafted Polypropylene Composites

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Journal of Materials Science & Technology 2008年第2期24卷 279-284页

作者： Xiaohua CHEN Jing HU Lingping ZHOU Wenhua LI Zi YANG yanguo wang College of Materials Science and Engineering Changsha University of Science and Technology Changsha 410076 China College of Materials Science and Engineering Hunan University Changsha 410082 China

Carbon nanotube （CNT）/maleic acid anhydride （MAH）-grafted polypropylene （PP） composites were prepared by in situ grafting method. Infrared spectroscopy showed that the CNTs were linked to PP by MAH grafting. The microstructures and calorimetry analysis indicated that the crystallization behaviors of the filled and unfilled PP were quite different. The addition of CNTs dramatically reduced the spherulite size, increased crystallization rate and improved the thermal stability of PP. These results confirmed the expected nucleant effect of CNT on the crystallization of PP. Scanning and transmission electron microscopy showed that the CNTs were dispersed homogeneously, indicating that the original CNT bundles were separated into individual tubes by the grafting.

关键词： Carbon nanotubes Chemical treatment Resins Crystallite size