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Rare Metals 2016年第9期35卷 691-700页

作者： Xiang chen Yun-Gui chen {2.-Bo Tang ding-Quan Xiao College of Engineering and technology Neijiang Teachers Normal UniversityNeijiang 641002China School of Materials science and Engineering Sichuan UniversityChengdu 610065China

The effects of the introduction of Ce to La（1-x）CexFe（11.5）Si（1.5） alloys on 1：13 phase formation mechanism,the first-order magnetic phase transition strengthening characteristics,and magnetocaloric property were studied,*** results show that the formation mechanisms of 1：13 and La Fe Si phases in La（1-x）CexFe（11.5）Si（1.5） alloys are the same as those of Ce2.e（17） and CeFe2.phases in Ce–Fe binary system,*** substitution of Ce in 1：13 phase which is limited can make the first-order magnetic phase transition characteristics strengthen,which can make thermal and magnetic hysteresis increase,the temperature interval of temperatureinduced phase transition decrease,and the critical magnetic field of field-induced magnetic phase transition（HC）increase,*** to the lattice shrink of 1：13phase with the increase in Ce content,the Curie temperatures（TC） show a linear *** maximum change in magnetic entropy gradually increases due to the decrease in temperature interval of temperature-induced phase transition,but the relative cooling capacities are all about80 Jákg-1at magnetic field of 2.T.

关键词： La1-xCexFe1 5Si1 5alloys Short-time annealing Large magnetocaloric effect Magnetocaloric materials

Major Scientific Achievements of the First china–Japan Cooperative GAME/HUBEX Experiment: A Historical Review

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Journal of Meteorological Research 2020年第4期34卷 659-674页

作者： Yihui ding Wen HU yong HUANG Fengjiao {2. National Climate Center China Meteorological AdministrationBeijing 100081 Key Laboratory of Atmospheric sciences and Satellite Remote Sensing of Anhui Province Anhui Meteorological BureauHefei 230031 Shouxian National Climatology Observatory Huaihe River Basin Typical Agro-Ecosystems Meteorology Field Experiment Station of China Meteorological AdministrationShouxian 232200

In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment(WCRP/GEWEX/GAME/HUBEX: World Climate Research Program/Global Energy and Water Cycle Experiment/Asian Monsoon Experiment/Huaihe River Basin Energy and Water Cycle Experiment) in the Huaihe River basin, Anhui Province of china. The main objective of this field experiment(HUBEX)was to investigate the multiple-scale structure characteristics, life cycles, and genesis and development mechanisms of the Meiyu system in East Asia as well as the cause of related flooding disasters. It was a joint china-Japan cooperative meteorological and hydrological observation experiment. On the basis of intensive observations, scientists from the two countries conducted follow-up investigations through collating and compiling data and performing scientific analysis during the following five years. It can be concluded that the HUBEX project has yielded comprehensive and remarkable achievements. This paper introduces the major scientific results derived from this field experiment and the ensuing investigations, and reassesses their merits and shortages for the purpose of providing useful experience and proposing new research targets as well as prospects for the initiation of a new joint scientific Meiyu experiment in the middle and lower Yangtze River basin.

关键词： Meiyu Huaihe River basin energy and water cycle meteorological and hydrological observations Huaihe River Basin Energy and Water Cycle Experiment(HUBEX)/Global Energy and Water Cycle Experiment(GEWEX)/Asian Monsoon Experiment(GAME)

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美国海军海洋学业务体系概述

舰船科学技术 2024年第1期46卷 180-185页

作者：张永垂胡王江邵晨李科丁亚梅国防科技大学气象海洋学院湖南长沙410073 中国人民解放军92.59部队天津300061 中国人民解放军92.92.队浙江宁波315100

美国海军海洋学通过对海洋环境的观测和预报,为海上军事行动提供评估和决策。本文详细梳理负责海洋学业务的美国海军气象海洋司令部及其下属的四级和五级指挥部业务体系。以美国海军海洋学业务部门参加一次军事演习为例,阐述各业务部门... 详细信息

美国海军海洋学通过对海洋环境的观测和预报,为海上军事行动提供评估和决策。本文详细梳理负责海洋学业务的美国海军气象海洋司令部及其下属的四级和五级指挥部业务体系。以美国海军海洋学业务部门参加一次军事演习为例,阐述各业务部门的职责。最后,对军事海洋学的发展提出了意见建议。

关键词：美国海军军事海洋气象海洋司令部业务体系

纳米CeO_2.Ni60复合粉末的高能球磨法制备及其表征

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兰州理工大学学报 2018年第3期44卷 12-16页

作者：胡勇陈威丁雨田张帆牛博龙兰州理工大学材料科学与工程学院甘肃兰州730050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室甘肃兰州730050

以Ni60粉末和纳米CeO_2.粒为原料,在氩气保护下采用高能球磨工艺制备了纳米CeO_2.Ni60复合粉末,并利用扫描电镜、X射线衍射和激光粒度分析仪等方法,对复合粉末的形貌、晶粒大小、微观应变及粒度分布进行表征和分析.结果表明:在球磨转速... 详细信息

以Ni60粉末和纳米CeO_2.粒为原料,在氩气保护下采用高能球磨工艺制备了纳米CeO_2.Ni60复合粉末,并利用扫描电镜、X射线衍射和激光粒度分析仪等方法,对复合粉末的形貌、晶粒大小、微观应变及粒度分布进行表征和分析.结果表明:在球磨转速为350r/min,球料比为10∶1的条件下,随着球磨时间的延长,Ni60粉末晶粒不断细化,纳米CeO_2.聚体逐渐解聚,当球磨时间为10h时,纳米CeO_2.粒均匀弥散分布在Ni60基体上,形成层片状复合粉末;经10h球磨后复合粉末的晶粒尺寸和微观应变分别为2..9nm和0.32.,并在球磨10h后,二者的变化趋于稳定.

关键词：高能球磨纳米复合粉末 Ni60粉末纳米CeO2.粒分散

The Application Study about Ground-Based GPS Precipitable Water Vapor in Shijiazhuang and Qinhuangdao Region

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The Application Study about Ground-Based GPS Precipitable Wa...

基于AMESim的大型磨齿机静压支承转台特性研究

2.10 3rd IEEE International Conference on Computer science and Information technology—ICCSIT 2.10

作者： Wang yong 1 2.1.College of Traffic and Surveying Hebei Polytechnic university Tangshan {2. 2.Key Laboratory of Mine Spatial Information Technologies (Henan Polytechnic university Henan Bureau of Surveying and Mapping) State Bureau of Surveying and Mapping Jiaozuo {2. ding Keliang School of Surveying and Civil Spatial Information Beijing university of Civil Engineering and Architecture Beijing {2. He Rong School of Surveying and Land Infomation Engineering Henan Polytechnic university Jiaozuo {2. Liu yanping College of Traffic and Surveying Hebei Polytechnic university Tangshan {2.

Water vapor is a highly variable parameter in atmospheric processes and it plays a crucial role in atmospheric motions on a wide range of scales in space and time. GPS technique has been widely used in retrieving precipitable water vapor. Firstly the article has retrieved precipitable water vapor of Qinhuangdao and Shijiazhuang stations by GPS technique. Then it has researched two aspects of precipitable water vapor. One is the spatial and temporal distribution characters of precipitable water vapor;the other is the relation between precipitable water vapor and actual rainfall. The value of GPS precipitable water vapor of Shijiazhuang is higher than the value of GPS precipitable water vapor of Qinhuangdao, which is accord to the formula that the precipitable water vapor is reduced from south to north. During the different time of a day, there are differ degree fluctuate which the min value present to morning and the max value present to evening. It also compared the GPS precipitable water vapor and actual rainfall. Although the time of max value about rainfall is not identical to the time of max value about precipitable water vapor, rainfall has occurred mostly in the time while the value of precpitable water vapor is high.

关键词： Global positioning system Precipitable water vapor Zenith tropospheric delay Zenith wet delay

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机床与液压 2024年第14期52卷 48-51页

作者：陈勇杨佳兆丁文政张虎于春建南京工程学院工业中心江苏南京211167 南京工大数控科技有限公司江苏南京211816

为提升大型数控磨齿机的加工精度,研究了磨齿机静压支承转台的整体结构和工况以及分析了求解油膜厚度和输出流量的理论模型,初步得出了偏载对油膜厚度具有较大影响。为了进一步验证,在分析现有参数设计方法的基础上,利用AMESim软件建立... 详细信息

为提升大型数控磨齿机的加工精度,研究了磨齿机静压支承转台的整体结构和工况以及分析了求解油膜厚度和输出流量的理论模型,初步得出了偏载对油膜厚度具有较大影响。为了进一步验证,在分析现有参数设计方法的基础上,利用AMESim软件建立系统模型,对不同工况和结构参数进行系统动态仿真分析。仿真结果表明:静压支承转台结构参数可以保证转台产生足够的承载力,流量脉动对油膜厚度变化率的影响不到0.4%,偏载对油膜厚度变化率的影响最大为13%,静态和动态仿真结果均与实际数据相符,性能测试结果满足磨床设计要求。

关键词：磨齿机静压支承转台恒流式静压导轨液压系统仿真 AMESim

Analyzing market performance via social media: a case study of a banking industry crisis

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science china(Information sciences) 2014年第5期57卷 33-50页

作者： JIANG CuiQing LIANG Kun chen Hsinchun ding {2. School of Management Hefei University of Technology department of Management Information Systems The University of Arizona

Analyzing market performance via social media has attracted a great deal of attention in the finance and machine-learning ***,the vast majority of research does not consider the enormous influence a crisis has on social media that further affects the relationship between social media and the stock *** article aims to address these challenges by proposing a multistage dynamic analysis *** this framework,we use an authorship analysis technique and topic model method to identify stakeholder groups and topics related to a special *** analyze the activities of stakeholder groups and topics in different periods of a crisis to evaluate the crisis’s influence on various social media ***,we construct a stock regression model in each stage of crisis to analyze the relationships of changes among stakeholder groups/topics and stock behavior during a ***,we discuss some interesting and significant results,which show that a crisis affects social media discussion topics and that different stakeholder groups/topics have distinct effects on stock market predictions during each stage of a crisis.

关键词： social media market performance stakeholder theory authorship analysis technique topic model

Commutators of Marcinkiewicz Integral with Rough Kernels on Sobolev Spaces

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Acta Mathematica Sinica,English Series 2011年第7期27卷 1345-1366页

作者： Yan Ping chen yong {2. Xin Xia WANG department of mathematics and {2. School of Applied ScienceUniversity of Science and Technology of Beijing Beijing 100083 P. R. China School of Mathematical sciences Beijing Normal UniversityLaboratory of Mathematics and Complex Systems (BNU) Ministry of Education Beijing 100875 P. R. China The College of mathematics and Systems science Xinjiang University U~'umqi 830046 P. R. China

In this paper, the authors give the boundedness of the commutator [b,μΩ,γ] from the homogeneous Sobolev space LP（R^n） to the Lebesgue space L^p（R^n） for 1 〈 p 〈 ∞, where μΩ,γ denotes the Marcinkiewicz integral with rough hypersingular kernel defined by μΩ,γf（x）=（∫0^∞｜∫｜x-y｜≤tΩ（x-y）/｜x-y｜^n-1f（y）dy｜^2.t/t^3＋2.）^1/2.with Ω∈L^1（S^n-1）for 0〈γ〈min（n/2.n/p）or Ω∈L（log＋L）^β（S^n-1）for｜1-2.p｜〈β〈1（0〈γ〈n/2.,respectively.

关键词： Marcinkiewicz integral commutator rough kernel Sobolev space Bony paraproduct

Variations in rare earth elements with environmental factors in lake surface sediments from 17 lakes in western china

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Journal of Mountain science 2021年第7期18卷 1811-1822页

作者： DU ding-ding {2. Liu-qin BAI yong-hui HU Hai-ping School of Earth sciences East China University of TechnologyNanchang 330013China State Key Laboratory of Nuclear Resources and Environment Nanchang 330013China School of Earth sciences Lanzhou UniversityLanzhou 730000China

Numerous lakes in western china are excellent sites for understanding environmental ***,what dominates rare earth element(REE) variations are still under debate in the lake environmental *** this study,we selected 2. surface sediment samples from 17 lakes(*** lakes,small water bodies,etc.) in the QinghaiTibet Plateau and Xinjiang *** samples were analyzed to reveal the behavior of the REEs and major *** REE patterns are characterized by light rare earth element(LREE) enrichment,weak Ce anomaly(0.84-0.98,0.94 on average) and negative Eu anomaly(0.53-1.00,0.67 on average).The homogeneous REE patterns may reflect similar REE of the source ***,the REE abundances showed some significant *** this study,water chemistry data analyses inferred that the highly REE values appear possibly in the saltwater lake,and also related to carbonate mineral,whereas p H played a minor role in REE *** large-scale lakes(*** Bosten and Lake Ulungur),the results showed that the relatively larger REE values are in the margins of ***,lower REE contents are towards the central *** study suggested that five major factors control the REE contents:(1) The REE tends to increase with the increase of the weathering intensity.(2. Likewise,heavy mineral(***,anatase,zircon,etc.) are probably primary in these sediments because they are highly enriched in the REE.(3) The contribution of Fe-Mn oxides is significant in sediments because their concentrations highly correlate with the REE.(4) The carbonate mineral(mainly calcite) played a significant role on the REE values in the lakes because the REEs are incorporated into the carbonate minerals generating the low REE concentrations.(5) Major element analysis,mineral analysis,and grain-size data analysis showed that the REE distribution is chiefly influenced by finer grain-size component of lake sediments due to the decreasing propor

关键词： Western china Lake surface sediments Rare earth elements Environmental factors

The effect of sea surface temperature increase on the potential habitat of Ommastrephes bartramii in the Northwest Pacific Ocean

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Acta Oceanologica Sinica 2016年第2期35卷 109-116页

作者： XU Jie chen Xinjun chen {2. ding Qi TIAN Siquan College of Marine sciences Shanghai Ocean University Shanghai 201306 China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Shanghai Ocean University Ministry of Education Shanghai 201306 China National Engineering Research Center for Oceanic Fisheries Shanghai Ocean University Shanghai 201306 China School of Marine sciences University of Maine Orono ME 04469 USA Collaborative Innovation Center for National Distant-water Fisheries Shanghai 201306 China

In the Northwest Pacific Ocean, the squid jigging fisheries from china, Japan and other countries and regions have targeted the west winter-spring cohort of neon flying squid（Ommastrephes bartramii） from August to November since the 1970 s. This squid is a short-lived ecological opportunist with a life-span of about one year,and its population is labile and recruitment variability is driven by the environment or climate change. This variability provides a challenge for ones to forecast the key habitats affected by climate change. The catch data of O. bartramii from Chinese squid jigging fishery and the satellite-derived sea surface temperature（SST） data are used in the Northwest Pacific Ocean from August to November of 1998 to 2.04, the SST preferences of *** corresponding to high values of catch per fishing day（CPUE） are determined and monthly potential habitats are predicted using a histogram analysis of the SST data. The possible changes in the potential habitats of O. bartramii in the Northwest Pacific Ocean are estimated under four climate change scenarios based on the Fourth Assessment Report（AR4） of the Intergovernmental Panel on Climate Change, i.e., 0.5, 1, 2.and 4°C increases in the SST because of the climate change. The results reveal an obvious poleward shift of the potential habitats of O. bartramii in the Northwest Pacific Ocean.

关键词： Ommastrephes bartramii sea surface temperature increase potential habitat Northwest Pacific Ocean