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Journal of Earth Science 2024年第1期35卷 144-154页

作者： Jing Zhao Li Zhang Xiaoyan Wang Jinglian Ge Min Xu Wei Chen Mao Luo Qianyong Liang Qiuhua yu Shuaibing Luo wenkun Qie Key Laboratory of Marine Mineral Resoures Ministry of Natural ResourcesGuangzhou Marine Geological SurveyChina Geological SurveyGuangzhou 511458China National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511458China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China

Understanding the spatial and temporal distribution of different paleontological communities in the southern South China Sea(SCS)is fundamental to explore its paleoclimatic and paleoenvironmental changes.In this study,foraminifera,pollen and diatoms from 100 surface sediment samples covering 40000 km^(2) of sea floor in the southern SCS were comprehensively investigated in terms of their assemblage and distribution.The results showed the existence of abundant foraminifera and pollen in most of the samples,although diatom communities were relatively scarce.Foraminifera were dominated by G.sacculifer,G.menardii,G.ruber,while diatoms were characterized by T.simonsenii,T.nitzschioides and T.longissima,indicating a typical tropical marine environment.The pollen assemblages showed a better reflection of montane rainforest,tropical rainforest and mangrove.The spatial differences among foraminifera assemblages may indicate the effect of water depth and a warmer environment in the southeast part of the study area,while the spatial patterns of diatom and pollen assemblages imply the influence of coastal current.Our study also noted that the compositions of paleontological communities in the SCS can vary significantly in a short distance,and synthesized studies on multiple biological groups are needed to reconstruct the Quaternary climate and the oceanographic environment.

关键词： southern South China Sea sediments foraminifera diatom pollen

综合地表与深部位移监测数据的滑坡多目标加权位移反分析方法

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测绘学报 2022年第10期51卷 2149-2159页

作者：戴粤戴吾蛟余文坤中南大学测绘与遥感科学系湖南长沙410083 湖南省精密工程测量与形变灾害监测重点实验室湖南长沙410083

针对滑坡参数反演存在的多目标优化问题,同时为弥补滑坡深部位移监测点位稀疏的不足,提出了一种综合地表与深部位移监测数据的滑坡多目标加权位移反分析方法。该方法利用地表与深部位移监测数据构建多目标位移反分析模型,采用抗差Helmer... 详细信息

针对滑坡参数反演存在的多目标优化问题,同时为弥补滑坡深部位移监测点位稀疏的不足,提出了一种综合地表与深部位移监测数据的滑坡多目标加权位移反分析方法。该方法利用地表与深部位移监测数据构建多目标位移反分析模型,采用抗差Helmert方差分量估计法计算各类位移观测量的抗差验后随机模型,优化反演模型的权参数。试验结果表明:深部位移信息量不足会导致位移反分析结果出现严重偏差,综合地表与深部位移信息的反演结果更为准确;基于抗差Helmert方差分量估计的多目标加权位移反分析方法不仅可以合理确定不同类型观测数据的权重,还能够有效抵制异常粗差对反演结果的影响,提高了反演计算精度。

关键词：滑坡变形监测多目标优化问题加权位移反分析模型抗差Helmert方差分量估计

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应用曲线积分的地震勘探多缆定位算法

石油地球物理勘探 2022年第6期57卷 1317-1324,I0003页

作者：段楚峰张昊楠匡翠林余文坤阮福明戴吾蛟中南大学地球科学与信息物理学院湖南长沙410083 中海油田服务股份有限公司物探事业部天津300451 海洋油气勘探国家工程研究中心北京100028

拖缆定位是海上拖缆地震勘探的一个关键环节,而准确的拖缆模型与定位算法是实现高精度拖缆定位的核心。现有的拖缆定位算法在多缆作业场景下存在数学模型不严密、定位网络观测值利用不充分的问题。为此,提出了一种基于曲线积分的海上地... 详细信息

拖缆定位是海上拖缆地震勘探的一个关键环节,而准确的拖缆模型与定位算法是实现高精度拖缆定位的核心。现有的拖缆定位算法在多缆作业场景下存在数学模型不严密、定位网络观测值利用不充分的问题。为此,提出了一种基于曲线积分的海上地震勘探多缆定位算法。首先,利用曲线积分构建严密的拖缆数学模型;然后,推导了该模型下不同类型观测值的误差方程;最后,通过仿真和实测数据对算法进行有效性验证。实验结果表明,该算法解获得的拖缆缆形与检波点位置精度优于传统算法,其中沿测线方向定位精度优于1m,垂直测线方向精度优于3m,可满足海上地震勘探作业及后续地震波数据分析的需求。

关键词：海上地震勘探拖缆定位曲线积分模型误差方程多缆定位

Quantum Spin Exchange Interactions to Accelerate the Redox Kinetics in Li–S Batteries

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Nano-Micro Letters 2024年第5期16卷 370-383页

作者： yu Du Weijie Chen yu Wang yue yu Kai Guo Gan Qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S batteries.Spin selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of catalysts.Herein,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial displacement.According to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S batter-ies.As a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 cycles.This work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

Light People:Professor Laura Na Liu

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Light(Science & Applications) 2024年第2期13卷 184-189页

作者： Hui Wang Cun yu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences130033ChangchunChina

Editorial The DNA nanotechnology outlines a new chapter in biological sciences,opening a new era of scientific and technological advancements.A pioneer of DNA nanotechnology,Professor Liu from the University of Stuttgart in Germany,our latest Light People,has been working at the interface,where nanophotonics meets biology and chemistry.On the path of scientific explorations.

关键词： chemistry. advancement pioneer

Macroporous Directed and Interconnected Carbon Architectures Endow Amorphous Silicon Nanodots as Low‑Strain and Fast‑Charging Anode for Lithium‑Ion Batteries

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Nano-Micro Letters 2024年第5期16卷 333-351页

作者： Zhenwei Li Meisheng Han Peilun yu Junsheng Lin Jie yu Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Shenzhen Engineering Lab for Supercapacitor MaterialsSchool of Material Science and EngineeringHarbin Institute of TechnologyShenzhenUniversity TownShenzhen 518055People’s Republic of China Songshan Lake Materials Laboratory Dongguan Dongguan 523808GuangdongPeople’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fabricating low-strain and fast-charging silicon-carbon composite anodes is highly desired but remains a huge challenge for lithium-ion batteries.Herein,we report a unique silicon-carbon composite fabricated by uniformly dis-persing amorphous Si nanodots(SiNDs)in carbon nanospheres(SiNDs/C)that are welded on the wall of the macroporous carbon framework(MPCF)by vertical graphene(VG),labeled as MPCF@VG@SiNDs/C.The high dispersity and amor-phous features of ultrasmall SiNDs(~0.7 nm),the flexible and directed electron/Li+transport channels of VG,and the MPCF impart the MPCF@VG@SiNDs/C more lithium storage sites,rapid Li+transport path,and unique low-strain property during Li+storage.Consequently,the MPCF@VG@SiNDs/C exhibits high cycle stability(1301.4 mAh g^(-1) at 1 A g^(-1) after 1000 cycles without apparent decay)and high rate capacity(910.3 mAh g^(-1),20 A g^(-1))in half cells based on industrial electrode standards.The assembled pouch full cell delivers a high energy density(1694.0 Wh L^(-1);602.8 Wh kg^(-1))and an excellent fast-charging capability(498.5 Wh kg^(-1),charging for 16.8 min at 3 C).This study opens new possibilities for preparing advanced silicon-carbon com-posite anodes for practical applications.

关键词： Amorphous Si nanodots Low-strain Fast-charging Lithium-ion batteries

顾及频间偏差的GNSS多频非组合PPP变形监测

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导航定位与授时 2023年第1期10卷 65-73页

作者：潘林李选平戴吾蛟余文坤中南大学地球科学与信息物理学院长沙410083 长沙金维信息技术有限公司系统设计部长沙410000

精密单点定位(PPP)技术有望解决长距离、大范围等监测场景难以找到稳定基准点的难题。现代化的全球卫星导航系统(GNSS)卫星纷纷开始播发多频信号,多频观测值融合理论上可提升PPP变形监测性能。为了充分利用多频冗余观测数据,详细研究了... 详细信息

精密单点定位(PPP)技术有望解决长距离、大范围等监测场景难以找到稳定基准点的难题。现代化的全球卫星导航系统(GNSS)卫星纷纷开始播发多频信号,多频观测值融合理论上可提升PPP变形监测性能。为了充分利用多频冗余观测数据,详细研究了每个频点的差分码偏差(DCB)和全球定位系统(GPS)存在的相位频率间卫星钟偏差(PIFCB)的改正方法,扩展了多频数据处理的严密理论模型,能够灵活处理GPS三频、Galileo五频和BDS-3五频观测数据。多频PPP振动监测实验结果表明,GPS三频PPP、BDS-3五频PPP、Galileo五频PPP较各自双频PPP位移监测精度可分别提升12%、13%和14%,表明多频PPP技术有利于提升PPP位移监测精度与稳定性。

关键词：变形监测精密单点定位多频数据处理全球卫星导航系统

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： WANG yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Effect of relative humidity on the desulfurization performance of calcium-based desulfurizer

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Journal of Environmental Sciences 2024年第4期138卷 179-188页

作者： Juan Lǖ yu Fu Haiyan yu HuanWang Zhe Wang Haiyan Chen School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Guangyuan Emergency Management bureau Guangyuan 628000China

Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance desulfurizers.In this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative humidities.The results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional desulfurizers.Also,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration performance.Sufficient contact with the nascent surface maximizes the formation of slaked lime.The experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative humidity.Compared with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional desulfurizers.This work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.

关键词： Dry desulfurization Relative humidity Desulfurization efficiency High-efficiency desulfurizer Quicklime digestion