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Regional disparities of phytoplankton in relation to different water masses in the Northwest Pacific Ocean during the spring and summer of 2017

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Acta Oceanologica Sinica 2020年第6期39卷 107-118页

作者： Gengming Lin Yanghang Chen Jiang Huang yanguo wang Youyin Ye Qingliang Yang Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China

The West Pacific Ocean is considered as the provenance center of global marine life and has the highest species diversity of numerous marine *** phytoplankton,as the primary producer at the base of the food chain,effects on climate change,fish resources as well as the entire ***,there are few large-scale surveys covering several currents with different hydrographic *** study aimed to explore the relationships between the spatio-temporal variation in phytoplankton community structure and different water masses.A total of 630 water samples and 90 net samples of phytoplankton were collected at 45 stations in the Northwest Pacific Ocean(21.0°–42.0°N,118.0°–156.0°E)during spring and summer 2017.A total of 281 phytoplankton taxa(>5μm)belonging to 61 genera were identified in the study *** distribution pattern of the phytoplankton community differed significantly both spatially and *** average abundances of phytoplankton in spring and summer were 797.07×10~2 cells/L and 84.94×10~2 cells/L,*** in spring or summer,the maximum abundance always appeared in the northern transition region affected by the Oyashio Current,where nutrients were abundant and diatoms dominated the phytoplankton community;whereas the phytoplankton abundance was very low in the oligotrophic Kuroshio region,and the proportion of dinoflagellates in total abundance increased *** horizontal distribution of phytoplankton abundance increased from low to high latitudes,which was consistent with the trend of nutrient distributions,but contrary to that of water temperature and *** the northern area affected by the Oyashio Current,the phytoplankton abundance was mainly concentrated in the upper 30 m of water column,while the maximum abundance often occurred at depths of 50–75 m in the south-central area affected by the Kuroshio *** correlation and redundancy analysis(RDA)showed that phytoplankton abundance was s

关键词： phytoplankton regional disparity species composition spatial distribution Northwest Pacific Ocean

Comparison of CMAS corrosion and sintering induced microstructural characteristics of APS thermal barrier coatings

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Journal of Materials Science & Technology 2019年第3期35卷 440-447页

作者： Yiyou Wu Hua Luo Canying Cai yanguo wang Yichun Zhou Li Yang Guangwen Zhou School of Materials Science and Engineering Xiangtan University Key Laboratory of Low Dimensional Materials & Application Technology of Ministry of Education Xiangtan University Department of Mechanical Engineering & Materials Science and Engineering Program State University of New York at Binghamton

The microstructural features of high-temperature sintered and CaO-MgO-Al_2O_3-SiO_2(CMAS) corroded air plasma sprayed Y_2O_3 stabilized ZrO_2(YSZ) thermal barrier coatings(TBCs) under the thermal gradient condition were comparatively studied. As-sprayed YSZ has a lamellar structure and the lamellae are composed of closely aligned columnar crystals. The sintered and the CMAS corroded YSZ coatings maintain the t'-ZrO_2 phase as the as-sprayed YSZ coating. The sintered YSZ remains the lamellar structure with reduced interlamellar gaps and grains coarsening. After the CMAS corrosion, the top layer of the YSZ coating keeps its lamellar structure consisting of some columnar grains with the CMAS infiltration into the intergrain gaps and the formation of striped Zr_2Y_2 O_7. The typical lamellar structure transforms into more equiaxed grains in the middle and bottom layers of the ceramic coating along with significant infiltration of amorphous CMAS and anorthite formation in the bottom layer owing to the high contents of Ca and Al.

关键词： YSZ thermal barrier coating APS CMAS corrosion Anorthite

In-situ potential mapping of space charge layer in Ga N nanowires under electrical fi eld by off-axis electron holography

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Progress in Natural Science:Materials International 2016年第2期26卷 163-168页

作者： Xiao Chen yanguo wang Jie Guo 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

In situ potential mapping of space charge（SC） layer in a single Ga N nanowire（NW） contacted to the Au metal electrode has been conducted using off-axis electron holography in order to study the space distribution of SC layer under electric biases. Based on the phase image reconstructed from the complex hologram the electrostatic potential at the SC layer was clearly revealed; the SC width was estimated to be about 76 nm under zero bias condition. In order to study dynamic interrelation between the SC layer and bias conditions, the variation of the electrostatic potential due to change of the SC widths respond to the different bias conditions have also been examined. The measured SC layers are found to vary between68 nm and 91 nm, which correspond to the saturated SC layers at the Ga N-Au contact under the forward and reverse bias conditions, respectively. By plotting the square widths of the SC layer against the applied voltages, donor density of Ga N NWs was derived to be about 4.3*10;cm;. Our experiments demonstrate that in-situ electron holography under electric fi eld can be a useful method to investigate SC layers and donor density in single NW and other heterostructures.

关键词： Space charge layer Electron holography In-situ TEM Semiconductor nanowire Semiconductor-metal contact

The hidden disintegration of cluster heterogeneity in Fe-based glass-forming alloy melt

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Progress in Natural Science:Materials International 2018年第6期28卷 696-703页

作者： Bangshao Dong Shaoxiong Zhou Jingyu Qin Ying Li Hui Chen yanguo wang Advanced Technology & Materials Co. Ltd. Central Iron & Steel Research Institute Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Nanjing Tengyuan Soft Magnetics Co.Ltd.

The evolution of liquid metal at high temperature is known much less than their solid states. This is partially due to that the message concerning clusters, metastable phase or heterogeneity in liquid is usually too slight to be traced. Here, we shed some light on the nature of structural evolution of Fe-based glass-forming alloy during overheating process by the investigation of high-temperature melt viscometry and first principles simulations. It was found that a structural transition around 1400 ℃ occurred in the melts of initial homogeneous ingot, heterogeneous ingot and amorphous ribbons jointly, and was confirmed by the results from differential scanning calorimeter(DSC), and ab initio molecular dynamics(AIMD). Combining these results with Fe-Si-B ternary phase diagram and the melting characteristics of Fe-B compounds, it is safe to conclude that the disintegration of Fe2B type clusters to Fe3B-type clusters leads to the observed transition. These results offer a significant reference for the preparation and property control of Fe-based amorphous alloys.

关键词： Fe-based glass-forming alloys Alloy melt Cluster heterogeneity Structural transition Viscosity

Effect of Co addition on crystallization and magnetic properties of FeSiBPCu alloy

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Progress in Natural Science:Materials International 2014年第6期24卷 649-654页

作者： Rui Xiang Shaoxiong Zhou Bangshao Dong Guangqiang Zhang Zongzhen Li yanguo wang Chuntao Chang China Iron & Steel Research Institute Group Advanced Technology & Materials Co. Ltd. Institute of Physics Chinese Academy of Sciences PO Box 603 Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Materials Technology & Engineering Chinese Academy of Sciences

The effects of Co addition on the microstructure,crystallization processes and soft magnetic properties of(Fe1 xCox)83Si4B8P4Cu1(x?0.35,0.5,0.65)alloys were *** experimental results demonstrated that the addition of Co decreased the thermal stability against crystallization of the amorphous phase,and thus improved the heat treatment temperature of this *** Co Si BPCu nanocrystalline alloys with a dispersedα0-Fe Co phase were obtained by appropriately annealing the as-quenched ribbons at 763 K for 10 ***α0-Fe Co with grains size ranging from 9 to 28 nm was identified in primary *** coercivity(Hc)markedly increased with increasing x and exhibited a minimum value at x0.35,while the saturation magnetic flux density(Bs)shows a slight ***(Fe0.65Co0.35)83Si4B8P4Cu1nanocrystalline alloy exhibited a high saturation magnetic flux density Bsof 1.68 T,a low coercivity,Hcof 5.4 A/m and a high effective permeability meof 29,000 at 1 k Hz.

关键词： Crystallization Soft magnetic properties Microstructure High temperature Nanocrystalline alloy

Zooplankton composition and distribution in the Lembeh Strait of North Sulawesi, Indonesia

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Acta Oceanologica Sinica 2018年第12期37卷 35-44页

作者： wang yanguo CHEN Xiaoyin XING Bingpeng SUN Rouxin FITRIA Nurul XIANG Peng wang Chunguang LIN Mao Third Institute of Oceanography Ministry of Natural Resources Research Center for Oceanography Indonesian Institute of Sciences

Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species(including 4 sp.) had been recognized, most of them belonged to *** followed with 43 species(including 1 sp.) were identified. The average abundance of zooplankton was(150.47±58.91) ind./m3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides,Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs.

关键词： zooplankton species composition dominant species distribution Lembeh Strait

Dynamic observation of oxygen vacancies in hafnia layer by in situ transmission electron microscopy

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Nano Research 2015年第11期8卷 3571-3579页

作者： Chao Li Yuan Yao Xi Shen yanguo wang Junjie Li Changzhi Gu Richeng Yu Qi Liu Ming Liu Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Laboratory of Nano-Fabfication and Novel Devices Integrated Technology Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China

The charge-trapping process, with HfO2 film as the charge-capturing layer, has been investigated by using in situ electron energy-loss spectroscopy and in situ energy-filter image under positive external bias. The results show that oxygen vacancies are non-uniformly distributed throughout the HfO2 trapping layer during the programming process. The distribution of the oxygen vacancies is not the same as that of the reported locations of the trapped electrons, implying that the trapping process is more complex. These bias-induced oxygen defects may affect the device performance characteristics such as the device lifetime. This phenomenon should be considered in the models of trapping processes.

关键词： charge-trapping flash in situ TEM electric field oxygen vacancy

Temporal and spatial variation of fish community and their nursery in a tropical seagrass meadow

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Acta Oceanologica Sinica 2018年第12期37卷 63-72页

作者： DU Jianguo wang yanguo PERISTIWADY Teguh LIAO Jianji MAKATIPU Petrus Christianus HUWAE Ricardo JU Peilong LOH Kar Hoe CHEN Bin Third Institute of Oceanography Ministry of Natural Resources Bitung Marine Life Conservation Research Center for Oceanography Indonesian Institute of Sciences College of Ocean and Earth Sciences Xiamen University Institute of Ocean and Earth Sciences University of Malaya

Fish species composition and spatio-temporal variability of the community were studied in a tropical seagrass meadow located in a lagoon in the eastern part of North Sulawesi. The diversity of fish community in the seagrass meadows was relatively high, with the Shannon-Wiener index ranging from 1.57 to 3.69. The family Apogonidae was the most dominant in abundance(8.27 ind./(100 m2)) and biomass(28.49 g/(100 m2)). At the species level,Apogon lateralis and Sphaeramia orbicularis were the most dominant species in abundance and biomass,respectively. For spatial distribution on species, the end, middle and mouth of the lagoon clustered together as a whole, which may be due to the substrate types found in those zones. The fish species, fish abundance and fish biomass were greater in the dry and wet seasons than in the transition season, which is explained by the strong monsoon, which provides a more suitable environment and food for the fish. The maximum length of 93.10% of the captured species was less than their length at maturity, indicating that seagrass meadows are nursery habitats for many fishes. Therefore, protection of the seagrass meadows is essential for fisheries and sustainable resource utilization.

关键词： seagrass meadows fish assemblages nursery function North Sulawesi

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基于重力异常增强的改进小子域滤波方法

石油地球物理勘探 2020年第1期55卷 206-216,12-13页

作者：王彦国黄远生张瑾东华理工大学放射性地质与勘探技术国防重点学科实验室江西南昌330013

小子域滤波是一种常用的重力异常边界拾取手段。传统小子域滤波子域划分重心不稳,易导致异常曲线出现扭曲。为此对小子域滤波的子域剖分模式进行改进,使其更合理地反映不同走向的构造;同时提出了基于迭代差分的稳定增强滤波解决小子域... 详细信息

小子域滤波是一种常用的重力异常边界拾取手段。传统小子域滤波子域划分重心不稳,易导致异常曲线出现扭曲。为此对小子域滤波的子域剖分模式进行改进,使其更合理地反映不同走向的构造;同时提出了基于迭代差分的稳定增强滤波解决小子域滤波易受高频干扰影响和识别异常界限能力不足的缺陷。模型试验表明,稳定增强异常改进型小子域滤波不仅计算稳定性强,而且检测出的边界与实际场源边界位置一致性较高。在鸭绿江盆地重力数据处理中,增强异常改进小子域滤波相对于常规算法可以获得更丰富的边界细节信息,而且检测出的异常界限与岩性接触带具有较好的一致性,同时计算结果中的负异常区域与研究区低密度岩石的分布也具有一定的对应关系,不仅验证了本文算法的有效性和实用性,还为研究区煤田勘查及地质—地球物理综合解释提供了可靠依据。

关键词：小子域滤波异常界限随机干扰增强异常鸭绿江盆地