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X-ray spectral evolution in an X-ray changing-look AGN NGC 13.5 with variable column density

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Research in Astronomy and Astrophysics 2021年第8期21卷 159-166页

作者： Hao Liu Qing-Wen Wu Yong-Quan Xue Ting-Gui Wang Jun Yang Heng-Xiao Guo zhi-Cheng He Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and space science University of Science and Technology of ChinaHefei 230026China Department of space Earth and EnvironmentChalmers University of TechnologyOnsala Space ObservatorySE-43992 OnsalaSweden Department of Physics and Astronomy 4129 Frederick Reines HallUniversity of CaliforniaIrvineCA92697-4575USA

X-ray changing-look active galactic nuclei(CL AGNs) are a subpopulation of AGNs,whose lineof-sight column densities increase/decrease within several *** physical mechanism for the variation of column density is *** reduce the X-ray data from XMM-Newton and Nu STAR observations for a CL AGN NGC 13.5 with strong variation of column *** X-ray spectrum quickly softens as the X-ray luminosity increases and optical-to-X-ray spectral index also increases as increasing of optical *** results support that NGC 13.5 also undergoes strong spectral evolution as that recently suggested for the optically selected CL AGNs with reappearance/disappearance of broad emission ***,the variation of column density may be driven by the variable disk winds during the strong evolution of disk/corona.

关键词： galaxies:active galaxies:Seyfert quasars:emission lines accretion accretion disks

地球科学和深空探测的引力场建模理论研究进展

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地球与行星物理论评（中英文） 2024年第5期55卷 501-512页

作者：尹智张克非段亚博刘军生穆庆禄中国矿业大学环境与测绘学院徐州221008 江苏海洋大学海洋技术与测绘学院连云港222005

不规则天体引力场建模是当前地球科学和深空探测研究领域面对的共同难题.本文梳理了这两个领域中引力场建模理论的发展历程以及近10年研究进展,重点介绍引力场多极展开理论和引力场势流模拟理论.引力场多极展开理论将电磁学和量子力学... 详细信息

不规则天体引力场建模是当前地球科学和深空探测研究领域面对的共同难题.本文梳理了这两个领域中引力场建模理论的发展历程以及近10年研究进展,重点介绍引力场多极展开理论和引力场势流模拟理论.引力场多极展开理论将电磁学和量子力学中常用的复变函数公式体系引入引力场研究领域,比实变函数公式体系更简洁地表述天体(内外部)引力场结构;通过充分利用复变函数运算规则,能直观有效解决与引力场相关的天体动力学问题.引力场势流模拟理论利用天体外部引力矢量和势流速度矢量的等价性(即两者都是无源无旋矢量场),将计算流体动力学数值计算方法引入引力场建模领域,通过求解势流速度场实现天体外部引力场建模;此理论不依赖于扰动理论,能有效克服常规方法在反演不规则天体引力场过程中存在的“解发散”问题.这两种引力场建模理论的共同创新性在于通过将其它领域中看似不相关的数学理论引入到本领域,实现本领域的问题求解和理论推进,对后续理论研究起到一定借鉴意义.此外,本文根据天体引力场的定义公式及其变体形式,对地球科学和深空探测领域已有的引力场建模理论研究进行分类、对比和分析,总结各自优缺点,对相关学者选用合适引力场建模方法提供有益参考.

关键词：引力场引力场建模边值理论深空探测不规则天体

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Theoretical predictions and experimental verification on the phase stability of enthalpy-stabilized HE TMREB_(2)s

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Journal of Materials science & technology 2022年第26期121卷 154-162页

作者： Ze Zhang Shizhen Zhu Fu-zhi Dai Huimin Xiang Yanbo Liu Ling Liu Zhuang Ma Shijiang Wu Fei Liu Kuang Sun Yanchun Zhou School of Materials science and Engineering Beijing Institute of TechnologyBeijing 100081China science and technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing 100076China National Key Laboratory of science and technology on Materials Under Shock and Impact Beijing 100081China Beijing Institute of technology Chongqing Innovation Center Chongqing 401120China Yangtze Delta Region Academy of Beijing Institute of technology Jiaxing 314019China Zibo Firststar New Material Incorporated Co. Ltd.Zibo 255000China Shanghai Chenhua science and technology Corporation Ltd. Shanghai 201804China

Transition metal diborides(TMB_(2)s)are the materials of choice in extreme environments due to their excellent thermal and chemical ***,the degradation of oxidation resistance of TMB_(2)s at elevated temperature still hinders their *** cope with this challenge,it is effective to incorporate rare earth elements to form high-entropy transition and rare-earth metal diborides(HE TMREBs).To obtain thermodynamically stable single-phase structures for HE TMREB_(2)s,a“16×16 mixed enthalpy matrix”is constructed using first-principles calculations to predict the single-phase formation ability of120 two-component diborides(TCBs).Through the use of the“16×16 mixed enthalpy matrix”of TCBs,specific combinations of TMB_(2)s and REB_(2)s that are most likely to form single-phase HE TMREB_(2)s are ***,based on the energy distribution of the local mixing enthalpies of all possible configurations,the enthalpy and entropy descriptors of HE TMREB_(2)s(RE=Sc,Lu,Tm,Er,Ho and Dy)are *** is found that the mixing enthalpy plays a critical role in the stability of the single-phase HE TMREB_(2)s,i.e.,HE TMREB_(2)s are enthalpy-stabilized *** experimental results further confirm that enthalpy dominates the thermodynamic domain and drives the stability of REB_(2)s in HE TMREB_(2)*** study validates that enthalpy-stabilized HE TMREB_(2)s can further expand the compositional space of ultrahigh temperature ceramics(UHTCs)and is expected to further improve the oxidation resistance and high temperature properties of UHTCs.

关键词： High-entropy ceramics Ultrahigh temperature ceramics First-principles calculation Mixing enthalpy Transition and rare earth metal diborides

Fine-grained gravity flow sedimentation and its influence on development of shale oil sweet sections in lacustrine basins in china

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Petroleum Exploration and Development 2023年第5期50卷 1013-1029页

作者： ZOU Caineng FENG Youliang YANG zhi JIANG Wenqi ZHANG Tianshu ZHANG Hong WANG Xiaoni ZHU Jichang WEI Qizhao Petrochina Research Institute of Petroleum Exploration and Development Beijing 100083China School of earth and space sciences Peking UniversityBeijing 100871China

The geological conditions and processes of fine-grained gravity flow sedimentation in continental lacustrine basins in china are analyzed to construct the model of fine-grained gravity flow sedimentation in lacustrine basin,reveal the development laws of fine-grained deposits and source-reservoir,and identify the sweet sections of shale *** results show that fine-grained gravity flow is one of the important sedimentary processes in deep lake environment,and it can transport fine-grained clasts and organic matter in shallow water to deep lake,forming sweet sections and high-quality source rocks of shale ***-grained gravity flow deposits in deep waters of lacustrine basins in china are mainly fine-grained high-density flow,fine-grained turbidity flow(including surge-like turbidity flow and fine-grained hyperpycnal flow),fine-grained viscous flow(including fine-grained debris flow and mud flow),and fine-grained transitional flow *** distribution of fine-grained gravity flow deposits in the warm and humid unbalanced lacustrine basins are controlled by lake-level fluctuation,flooding events,and lakebed *** the lake-level rise,fine-grained hyperpycnal flow caused by flooding formed fine-grained channel–levee–lobe system in the flat area of the deep *** the lake-level fall,the sublacustrine fan system represented by unconfined channel was developed in the flexural slope breaks and sedimentary slopes of depressed lacustrine basins,and in the steep slopes of faulted lacustrine basins;the sublacustrine fan system with confined or unconfined channel was developed on the gentle slopes and in axial direction of faulted lacustrine basins,with fine-grained gravity flow deposits possibly existing in the lower *** the fourth-order sequences,transgression might lead to organic-rich shale and fine-grained hyperpycnal flow deposits,while regression might cause fine-grained high-density flow,surge-like turbidity flow,fine-grained de

关键词： fine-grained deposit hyperpycnal flow deposit fine-grained debris flow deposit muddy flow deposit fine-grained transitional flow deposit reservoir sweet section organic-rich source rock shale oil

Multi-geomagnetic-component assisted localization algorithm for hypersonic vehicles

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2021年第5期22卷 357-368页

作者： Kai CHEN Wen-chao LIANG Cheng-zhi ZENG Rui GUAN School of Astronautics Northwestern Polytechnical UniversityXi'an 710072China china Aerodynamics Research and Development Center Mianyang 621000China

Owing to the lack of information about geomagnetic anomaly fields,conventional geomagnetic matching algorithms in near space are prone to ***,geomagnetic matching navigation algorithms for hypersonic vehicles are also prone to divergence or *** address this problem,we propose a multi-geomagnetic-component assisted localization(MCAL)algorithm to improve positioning accuracy using only the information of the main geomagnetic ***,the main components of the geomagnetic field and a mathematical representation of the earth’s geomagnetic field(World Magnetic Model 2015)are *** mathematical relationships between the geomagnetic components are given,and the source of geomagnetic matching error is *** then propose the MCAL *** algorithm uses the intersections of the isopleths of the geomagnetic components and a decision method to estimate the real position of a carrier with high positioning ***,inertial/geomagnetic integrated navigation is simulated for hypersonic boost-glide *** simulation results demonstrate that the proposed algorithm can provide higher positioning accuracy than conventional geomagnetic matching *** the random error range is±3. nT,the average absolute latitude error and longitude error of the MCAL algorithm are 151 m and 511 m lower,respectively,than those of the Sandia inertial magnetic aided navigation(SIMAN)algorithm.

关键词： Geomagnetic navigation Isopleth Geomagnetic components Integrated navigation Kalman filter

Composition analysis of colored dissolved organic matter in Taihu Lake based on three dimension excitation-emission fuorescence matrix and PARAFAC model, and the potential application in water quality monitoring

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Journal of Environmental sciences 2007年第7期19卷 787-791页

作者： WANG zhi-gang LIU Wen-qing ZHAO Nan-jing LI Hong-bin ZHANG Yu-jun SI-MA Wei-cang LIU Jian-guo School of earth and space science University of Science and Technology of China Hefei 230026 China. Key Laboratory of Environmental Optics and technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China

Taihu Lake is one of the five biggest lakes in china. Surface water samples from 26 sampling sites of Taihu Lake were collected. Furthermore wet chemical analysis （CODCr and BOD5） and measurement of three dimensional excitation-emission matrix （3.EEM） spectra in the laboratory have been conducted. Using parallel factor analysis （PARAFAC） model, three components of colored dissolved organic matter （CDOM） have been identified successfully, based on the analysis of 3.EEM data. The characteristics of the three components also have been described by comparing them to some components of CDOM, identified in earlier researches. Meanwhile, spatial variations of concentration for the three components in Taihu Lake have been analyzed, and the result indicates that the concentration of component 1 depends more on the situation of wastewater pollution and can be used as the indicator of wastewater pollution. The relationship between the concentrations of the three components and results of the wet chemical analysis show that none of the three components can be used as indicators of gross organic matter in water. However, the concentrations of all the three components have obvious linear relationships with the BOD5 value, especially for component 1 （r = 0.72878）. Finally, the potential applications of the composition analysis based on 3.EEM and PARAFAC model in water quality monitoring have been illuminated.

关键词： 3.EEM Taihu Lake monitoring of water quality CDOM PARAFAC

What are the Lacustrine Fine-Grained Gravity Flow Sedimentation Process and the Genetic Mechanism of Sweet Sections for Shale Oil?

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Journal of earth science 2022年第5期33卷 1321-1323页

作者： Caineng Zou Youliang Feng zhi Yang Wenqi Jiang Songqi Pan Tianshu Zhang Xiaoni Wang Jichang Zhu Jiarui Li Research Institute of Petroleum Exploration and Development PetroChinaBeijing100083China School of earth and space sciences Peking UniversityBeijing100871China

0 INTRODUCTION Oil in continental Basins is the main contributor to petroleum reserves and production in *** exploration targets of the oil in continental Basins have experienced a transformation from conventional oil,whose reservoirs are mainly composed of coarse-grained deposits outside the lacustrine basin,and coarse-medium-grained sediments deposited near the shoreline of the lacustrine basin.

关键词： china lacustrine continental

Mapping the potential for offshore aquaculture of salmonids in the Yellow Sea

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Marine Life science & technology 2022年第3期4卷 329-342页

作者： Shuang‑En Yu Shuang‑Lin Dong zhi‑Xin Zhang Yu‑Yang Zhang Gianluca Sarà Jie Wang Yun‑Wei Dong Key Laboratory of Mariculture of Ministry of Education College of FisheriesOcean University of ChinaQingdao 266003China Function Laboratory for Marine Fisheries science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266235China CAS Key Laboratory of Tropical Marine Bio‑Resources and Ecology South China Sea Institute of OceanologyInnovation Academy of South China Sea Ecology and Environmental EngineeringChinese Academy of SciencesGuangzhou 510301China Laboratory of Ecology Department of Earth and Marine SciencesUniversity of Palermo90128 PalermoItaly

Mariculture has been one of the fastest-growing global food production sectors over the past three *** the congestion of space and deterioration of the environment in coastal regions,offshore aquaculture has gained increasing *** salmon(Salmo salar)and rainbow trout(Oncorhynchus mykiss)are two important aquaculture species and contribute to 6.1%of world aquaculture production of *** the present study,we established species distribution models(SDMs)to identify the potential areas for offshore aquaculture of these two cold-water fish species considering the mesoscale spatio-temporal thermal heterogeneity of the Yellow *** values of the area under the curve(AUC)and the true skill statistic(TSS)showed good model *** suitability index(SI),which was used in this study to quantitatively assess potential offshore aquaculture sites,was highly dynamic at the surface water ***,high SI values occurred throughout the year at deeper water *** potential aquaculture areas for *** and *** in the Yellow Sea were estimated as 52,270±3.75(95%confidence interval,CI)and 146,83.±15,023.km^(2),*** results highlighted the use of SDMs in identifying potential aquaculture areas based on environmental *** the thermal heterogeneity of the environment,this study suggested that offshore aquaculture for Atlantic salmon and rainbow trout was feasible in the Yellow Sea by adopting new technologies(e.g.,sinking cages into deep water)to avoid damage from high temperatures in summer.

关键词： Aquaculture potential Offshore aquaculture Oncorhynchus mykiss Salmo salar Species distribution models The Yellow Sea Cold Water Mass

广域电磁法在深部矿产勘查中的应用——以铜陵冬瓜山铜矿为例

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矿产勘查 2024年第9期15卷 1593-1606页

作者：肖晓李银航汤井田刘寄仁徐锦通杨智杨亮周聪中南大学地球科学与信息物理学院湖南长沙410083 中南大学有色金属成矿预测与地质环境监测教育部重点实验室湖南长沙410083 中南大学有色资源与地质灾害探查湖南省重点实验室湖南长沙410083 湖南文理学院计算机与电气工程学院湖南常德415000 东华理工大学核资源与环境国家重点实验室江西南昌330013

铜陵市冬瓜山铜矿是中国目前最大的现代化井下坑采铜矿山,目前浅部矿产开发已近成熟;矿体埋深在-690~-1007 m,开采历史已经超过50年。为在冬瓜山铜矿床地区寻找第二成矿空间,查明区内-1~-3.km深度的地层、构造及岩浆岩分布,揭露和成矿... 详细信息

铜陵市冬瓜山铜矿是中国目前最大的现代化井下坑采铜矿山,目前浅部矿产开发已近成熟;矿体埋深在-690~-1007 m,开采历史已经超过50年。为在冬瓜山铜矿床地区寻找第二成矿空间,查明区内-1~-3.km深度的地层、构造及岩浆岩分布,揭露和成矿密切相关的奥陶系—志留系界面的空间分布,本文针对冬瓜山铜矿强电磁干扰的勘探环境,开展了三维广域电磁勘探。通过现场干扰情况调查和数据采集试验设计了合理的广域电磁数据采集参数,获得了高质量广域电磁数据;在对强干扰区含噪数据进行精细去噪后,开展了拟二维反演;综合区域物性资料、钻孔资料、拟二维反演结果以及巷道揭露的1 000 m以浅的地层、岩体和矿体空间分布,开展了基于地质模型和岩石物性引导的广域电磁三维反演,验证了探测区1 000 m以浅的精细电性结构,并遵循“从已知到未知,从浅部到深部”的解译原则,推断了-1~-3.km范围内深部岩体及奥陶系—志留系界面的空间分布。研究成果可为冬瓜山矿体深边部找矿、成矿靶区预测及钻探选址提供了地球物理依据。

关键词：广域电磁法深部矿产勘查精细去噪三维反演