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Vegetation changes across the Eocene-Oligocene transition:Global signals *** development

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Science China Earth Sciences 2024年第9期67卷 2937-2952页

作者： mengxiao WU Lutz KUNZMANN Shufeng LI Vasilis TEODORIDIS Zhekun zhou Tao SU CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Senckenberg Natural History Collections Dresden Konigsbrücker LandstraBe 159Dresden 01109Germany Department of Biology and Environmental Studies Faculty of EducationCharles UniversityMagdalény Rettigové411639 Prague 1Czech Republic State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China

The Eocene-Oligocene transition(EOT)marked a rapid global cooling event,often considered as the beginning of the modern icehouse *** by various factors,including tectonic activity and paleogeographic settings,the terrestrial records indicate a diverse response of fauna and vegetation to this global *** examined nine macrofossil assemblages from seven fossil localities on the southeastern margin of the Tibetan Plateau and from the mid-latitudinal Europe ranging from the latest Bartonian and Priabonian(37.71-33.9 Ma)to the Rupelian(33.9-27.82 Ma).Our aims were to trace and compare the vegetation history of both regions in the late Eocene and early *** results show that both regions experienced changes in vegetation composition in response to climate change,characterized by a decrease in the percentages of broad-leaved evergreen elements and distinctive changes in general vegetation types.A general change in the overall vegetation type from subtropical broad-leaved evergreen forests in the late Eocene to temperate broad-leaved mixed deciduous evergreen forests,or mixed mesophytic forests,in the early Oligocene is recognized in both *** results indicate a clear change in leaf architecture,leaf margin states,and secondary venation types in the mid-latitudinal Europe,while the results from the southeastern margin of the Tibetan Plateau show a distinct reduction in leaf *** data suggest that both global and regional factors played key roles in shaping the vegetation in the two regions.

关键词： Eocene-Oligocene transition Plant fossil Paleoclimate Leaf architecture Biodiversity

2013年夏季南极南设得兰群岛周边海域透光层水团结构

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极地研究 2020年第1期32卷 90-101页

作者：周梦潇朱国平上海海洋大学海洋科学学院上海201306 上海海洋大学极地研究中心上海201306 大洋渔业资源可持续开发教育部重点实验室极地海洋生态系统研究室上海201306 国家远洋渔业工程技术研究中心上海210306

南设得兰群岛位于德雷克海峡南侧,南经布兰斯菲尔德海峡与南极半岛相望。该区域一直是南大洋海洋学研究的热点区域,近些年已成为南极磷虾渔业的重要作业区。透光层作为海洋生物活动最为集中的区域,也是海洋中生产力最为丰富的区域。了... 详细信息

南设得兰群岛位于德雷克海峡南侧,南经布兰斯菲尔德海峡与南极半岛相望。该区域一直是南大洋海洋学研究的热点区域,近些年已成为南极磷虾渔业的重要作业区。透光层作为海洋生物活动最为集中的区域,也是海洋中生产力最为丰富的区域。了解透光层水团的特性及变化,一方面可为南极半岛海洋学研究提供基础信息,同时也可为南极磷虾等中上层海洋生物的分布及其致因提供科学支撑。通过分析2013年1月至3月南设得兰群岛周边海域5个断面的透光层温、盐数据,本研究梳理了该区域的水团属性和分布。结果显示,南设得兰群岛北侧较深水区水团垂向结构明显,由上至下依次为南极夏季表层水、冬季水和绕极深层水。位于南设得兰群岛南侧的布兰斯菲尔德海峡内,威德尔海过渡水特征几乎占据了整个布兰斯菲尔德海峡。但布兰斯菲尔德海峡西南侧水团结构较为复杂,包括了威德尔海过渡水、别林斯高晋海过渡水和德雷克海峡水等。阐明南设得兰群岛周边复杂的水团结构对于进一步开展南大洋生物-物理相互作用研究具有重要的科学意义。

关键词：南设得兰群岛水团南极绕极流绕极深层水布兰斯菲尔德海峡透光层

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镍铁渣粉对混凝土抗硫酸盐侵蚀性能的影响

清华大学学报（自然科学版） 2017年第3期57卷 306-311页

作者：王强石梦晓周予启余成行清华大学土木工程系北京100084 中建一局集团建设发展有限公司北京100102 北京市中超混凝土有限责任公司北京100024

为研究镍铁渣粉对混凝土抗硫酸盐侵蚀性能的影响规律和机理,该文测定了混凝土在硫酸盐侵蚀试验开始前的连通孔隙率和电通量,开展了硫酸盐溶液干湿循环和高温浸泡2种侵蚀性试验。试验结果表明:2种硫酸盐侵蚀性试验方法的结果是一致的;随... 详细信息

为研究镍铁渣粉对混凝土抗硫酸盐侵蚀性能的影响规律和机理,该文测定了混凝土在硫酸盐侵蚀试验开始前的连通孔隙率和电通量,开展了硫酸盐溶液干湿循环和高温浸泡2种侵蚀性试验。试验结果表明:2种硫酸盐侵蚀性试验方法的结果是一致的;随着电炉镍铁渣粉掺量的增加,混凝土的连通孔隙率增大,抗硫酸盐侵蚀性能降低;在高炉镍铁渣粉掺量30%的范围内,随着掺量的增加,混凝土的连通孔隙率减小,氯离子渗透性等级降低,抗硫酸盐侵蚀性能提高;高炉镍铁渣粉对混凝土抗硫酸盐性能的增强作用效果不及高炉矿渣粉,尤其在掺量较大的情况下。

关键词：镍铁渣粉硫酸盐侵蚀连通孔隙率氯离子渗透性

Parallel Physics-Informed Neural Networks Method with Regularization Strategies for the Forward-Inverse Problems of the Variable Coefficient Modified KdV Equation

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Journal of Systems Science & Complexity 2024年第2期37卷 511-544页

作者： zhou Huijuan School of Science Shanghai Maritime UniversityShanghai 201306China

This paper mainly introduces the parallel physics-informed neural networks(PPINNs)method with regularization strategies to solve the data-driven forward-inverse problems of the variable coefficient modified Korteweg-de Vries(VC-MKdV)*** the forward problem of the VC-MKdV equation,the authors use the traditional PINN method to obtain satisfactory data-driven soliton solutions and provide a detailed analysis of the impact of network width and depth on solving accuracy and ***,the author finds that the traditional PINN method outperforms the one with locally adaptive activation functions in solving the data-driven forward problems of the VC-MKdV *** for the data-driven inverse problem of the VC-MKdV equation,the author introduces a parallel neural networks to separately train the solution function and coefficient function,successfully addressing the function discovery problem of the VC-MKdV *** further enhance the network’s generalization ability and noise robustness,the author incorporates two regularization strategies into the *** amount of numerical experimental data in this paper demonstrates that the PPINNs method can effectively address the function discovery problem of the VC-MKdV equation,and the inclusion of appropriate regularization strategies in the PPINNs can improves its performance.

关键词： Data-driven forward-inverse problems parallel physics-informed neural networks regularization strategies variable coefficient modified KdV equation

Influence of stearic acid surface modification on flowability and agglomeration of battery grade Li_(2)CO_(3)powder

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Particuology 2024年第9期92卷 263-277页

作者： Ming zhou Lithium Industry Center Zhejiang New Era Zhongneng Technology Co.Ltd.Shaoxing312000China

This work investigates the flow and agglomeration behaviors of battery grade Li_(2)CO_(3)powder and the influence of stearic acid surface *** degree of agglomeration is directly related to the uniformity of Li_(2)CO_(3)and its powder *** to the Chinese National Nonferrous Metal Industry Standard,battery grade Li_(2)CO_(3)powder has D50 equal to 3–8μm which belongs to a micron-sized superfine ***,with the extension of storage time,the serious agglomeration phenomenon occurs due to the large specific surface area and rough and irregular powder *** Hausner ratio(HR)of the unmodified sample increases from 1.14 to 1.41,and the corresponding flowability is classified as good to ***,among samples with doping stearic acid,the optimum amount of it is 0.10 wt%which exhibits an extremely stable HR value from 1.14 to ***,after 156 days,the repose angle(AR)obtained for samples without surface modification and using 0.10 wt%stearic acid are calculated to be 49°and 28°,*** on the values of HR and AR,the flowability of the unmodified sample is poor while the sample modified with 0.10 wt%of stearic acid still maintain excellent powder flow ***,The LiMn_(2)O_(4)cathode material synthesized from modified Li_(2)CO_(3)powder with a stearic acid content of 0.10 wt%exhibits good crystallinity and comparable electrochemical performance to that prepared by commercial Li_(2)CO_(3).These results indicate that stearic acid has the potential to be an ideal modifier for battery grade Li_(2)CO_(3)powder that needs to be kept for a long time.

关键词： Battery grade Li_(2)CO_(3)powder Flowability Surface modification Stearic acid

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颅内动脉瘤相关基因的共表达网络构建与分析

中华医学杂志 2019年第7期99卷 525-531页

作者：廖宝周凤坤钟松辛周远方覃燕生周梦晓秦超广西医科大学第一附属医院神经内科南宁530021

目的利用生物信息学分析颅内动脉瘤(IA)的公共数据库中的表达谱芯片数据,为疾病机制研究提供重要信息。方法基于数据集(GSE75436)进行加权基因共表达网络分析(WGCNA)构建其基因共表达网络,并识别枢纽基因;同时,使用在线工具DAVID对... 详细信息

目的利用生物信息学分析颅内动脉瘤(IA)的公共数据库中的表达谱芯片数据,为疾病机制研究提供重要信息。方法基于数据集(GSE75436)进行加权基因共表达网络分析(WGCNA)构建其基因共表达网络,并识别枢纽基因;同时,使用在线工具DAVID对与IA具有高度相关的模块进行GO功能富集及KEGG通路分析。结果筛选出三个与IA相关的模块,以及识别了棕色模块中的14个枢纽基因COL3A1、SPARC、CDH11、COL5A1、HOPX、CLEC11A、GALNT10、ADAMTS2、CEMIP、KIAA1755、COL11A1、ZIC2、CDKN2A和LINC00460;GO分析显示棕色模块主要富集在细胞外基质组织、胶原蛋白分解代谢过程、细胞黏附等生物过程;KEGG分析显示棕色模块参与了ECM-受体相互作用、局部粘连、蛋白质消化和吸收、PI3K-Akt信号通路等通路。结论基于WGCNA,我们识别出了对IA发生发展至关重要的模块与枢纽基因,它们可能成为潜在的生物标志物和(或)治疗靶点。

关键词：颅内动脉瘤加权基因共表达网络分析基因共表达网络

Phase field modeling of ferroelastic variant switching in yttria-stabilized t'zirconia with strain gradient elasticity and interface tension

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Science China(Technological Sciences) 2024年第5期67卷 1443-1457页

作者： zhou QianQian WEI YueGuang zhou YiChun YANG Li College of Engineering BIC-ESATPeking UniversityBeijing100871China School of Advanced Materials and Nanotechnology Xidian UniversityXi’an710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an710126China

The 6–8 wt%yttria-stabilized zirconia with a tetragonal structure(t’-YSZ)is extensively employed in thermal barrier *** exceptional fracture toughness of t’-YSZ can be attributed to its distinctive ferroelastic toughening *** and interface tension play a critical role in ferroelastic variant switching at the micro-and *** paper presents an original thermodynamically consistent phase field(PF)theory for analyzing ferroelastic variant switching at the micro-and nano-scale of t’-*** theory incorporates strain gradient elasticity using higher-order elastic energy and interface tension tensor via geometric nonlinearity to represent biaxial tension resulting from interface ***,a mixed-type formulation is employed to implement the higher-order theory through the finite element *** an interface in equilibrium,the effects of strain gradient elasticity result in a more uniform distribution of stresses,whereas the presence of interface tension tensor significantly amplifies the stress magnitude at the *** introduction of an interface tension tensor increases the maximum value of stress at the interface by a factor of 4 to *** nucleation and evolution of variants at a pre-existing crack tip in a mono-phase t’-YSZ have also been *** strain gradient elasticity is capable of capturing the size effect of ferroelastic variant switching associated with microstructures in ***,when the grain size approaches that of the specimen,the critical load required for variant switching at the crack tip increases,resulting in greater dissipation of elastic energy during ferroelastic variant ***,the interface tension accelerates the evolution of *** presented framework exhibits significant potential in modeling ferroelastic variant switching at the micro-and nano-scale.

关键词： thermodynamics strain gradient elasticity interface tension phase field method ferroelastic variant switching

Deep-reinforcement-learning-based UAV autonomous navigation and collision avoidance in unknown environments

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Chinese Journal of Aeronautics 2024年第3期37卷 237-257页

作者： Fei WANG Xiaoping ZHU zhou zhou Yang TANG School of Astronautics Northwestern Polytechnical UniversityXi’an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

In some military application scenarios,Unmanned Aerial Vehicles(UAVs)need to perform missions with the assistance of on-board cameras when radar is not available and communication is interrupted,which brings challenges for UAV autonomous navigation and collision *** this paper,an improved deep-reinforcement-learning algorithm,Deep Q-Network with a Faster R-CNN model and a Data Deposit Mechanism(FRDDM-DQN),is proposed.A Faster R-CNN model(FR)is introduced and optimized to obtain the ability to extract obstacle information from images,and a new replay memory Data Deposit Mechanism(DDM)is designed to train an agent with a better *** training,a two-part training approach is used to reduce the time spent on training as well as retraining when the scenario *** order to verify the performance of the proposed method,a series of experiments,including training experiments,test experiments,and typical episodes experiments,is conducted in a 3D simulation *** results show that the agent trained by the proposed FRDDM-DQN has the ability to navigate autonomously and avoid collisions,and performs better compared to the FRDQN,FR-DDQN,FR-Dueling DQN,YOLO-based YDDM-DQN,and original FR outputbased FR-ODQN.

关键词： Faster R-CNN model Replay memory Data Deposit Mechanism(DDM) Two-part training approach Image-based Autonomous Navigation and Collision Avoidance(ANCA) Unmanned Aerial Vehicle(UAV)

Oxidation of emerging organic contaminants by in-situ H_(2)O_(2) fenton system

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Green Energy & Environment 2024年第3期9卷 417-434页

作者： Yuqin Ni Chuxiang zhou Mingyang Xing Yi zhou State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes School of Resources&Environmental EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Advanced Materials and Institute of Fine Chemicals National Engineering Laboratory for Industrial Wastewater TreatmentSchool of Chemistry and Molecular EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China Department of Applied Natural Sciences Technische Hochschule LubeckMonkhofer Weg 23923562 LubeckGermany

The existence and risk of emerging organic contaminants(EOCs)have been under consideration and paid much effort to degrade these *** system is one of the most widely used technologies to solve this *** original Fenton system relies on the hydroxyl radicals produced by Fe(Ⅱ)/H_(2)O_(2) to oxidize the organic ***,the application of the Fenton system is limited by its low iron cycling efficiency and the high risks of hydrogen peroxide transportation and *** introduction of external energy(including light and electricity etc.)can effectively promote the Fe(Ⅲ)/Fe(Ⅱ)cycle and the reduction of oxygen to produce hydrogen peroxide in *** review introduces three in-situ Fenton systems,which are electro-Fenton,Photo-Fenton,and chemical *** mechanism,influencing factors,and catalysts of these three in-situ Fenton systems in degrading EOCs are discussed *** review strengthens the understanding of Fenton and in-situ Fenton systems in degradation,offering further insight into the real application of the in-situ Fenton system in the removal of EOCs.

关键词： In-situ H_(2)O_(2)production Fenton Emerging organic contaminants Photocatalysis Electrocatalysis