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Sentinel-1 EW mode dataset for Antarctica from 2014–2020 produced by the CASEarth Cloud Service Platform

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Big Earth Data 2022年第4期6卷 385-400页

作者： Dong Liang Huadong Guo Lu Zhang Haipeng Lia xuezhi wang Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina International Research Center of Big Data for Sustainable Development Goals BeijingChina Computer Network Information Center Chinese Academy of SciencesBeijingChina

Antarctica plays an important role in research on global change,and its unique geography,ocean,climate,and environment pro-vide an ideal place for humankind to understand Earth’s evolution.Remote sensing provides an effective means to monitor and observe large-scale processes on the continent.Synthetic aperture radar(SAR)in particular provides the capability for all-weather Earth observation.The Sentinel-1A and Sentinel-1B SAR satellites have ideal ground coverage and imaging frequency for observing Antarctica.This study developed a dataset of 69,586 Sentinel-1 EW mode satellite images of the Antarctic ice sheet from October 2014 to December 2020.The dataset was processed with the European Space Agency Sentinel Application Platform(SNAP)and a Python batch scheduling tool on the Big Earth Data Cloud Service Platform of the Chinese Academy of Sciences Big Earth Data Science Engineering Program(CASEarth).Several data processing operations were implemented to process the raw dataset,including radiometric calibration,invalid edge removal,geocoding,data reprojection to an Antarctic projection,data compression to TIFF format,and construction of image pyramids.The dataset is avail-able at http://***/10.11922/sciencedb.j00076.00085.

关键词： Big Earth data CASEarth cloud computing Sentinel-1 Antarctica

Ultralow oxygen ion diffusivity in pyrochlore-type La2(Zr0.7Ce0.3)2O7

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Journal of Materials Science & Technology 2022年第7期102卷 174-185页

作者： Junwei Che Xiangyang Liu xuezhi wang Quan Zhang Erhu Zhang Gongying Liang Shengli Zhang MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter School of Physics Xi'an Jiaotong University State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Department of Applied Physics School of Science Chang'an University

Thermally grown oxides(TGOs) at the ceramic top-coat/metallic bond-coat interface are a pressing challenge in advanced thermal barrier coating(TBC) systems as they can affect the performance and service lifetime of TBCs.Thus,developing novel TBC materials with ultralow oxygen ion diffusivity is very urgent.In this study,we reported the diffusive properties of oxygen ions in a novel pyrochlore-type La2(Zr0.7Ce0.3)2O7(LZ7 C3) material.The measured ionic conductivity and atomistic simulation revealed that the oxygen ion diffusivity in LZ7 C3 grains is two orders of magnitude lower than that in conventional8 wt.% yttria-stabilized zirconia(8 YSZ) grains.This is due to the relatively high energy barrier for oxygen hopping in LZ7 C3.In addition,it was found that enhancing the order distribution of cations is a strategy to reduce the intrinsic oxygen diffusion of pyrochlore-type oxides.On the other hand,we observed that La3+cations segregate at the grain boundaries(GBs) of LZ7 C3,which results in the electrostatic potential at GBs being comparable to that in the bulk.Furthermore,we found that the oxygen ion diffusion is facilitated at the GBs of LZ7 C3 due to the stretched O-Zr/Ce bond and the low coordination at GBs.However,the segregations of Y3+cations and the increase in the number of oxygen vacancies resulted in the formation of an electrostatic layer at the GBs of 8 YSZ,which shielded the oxygen ion diffusion.Despite this,the oxygen ion diffusivity in LZ7 C3 was still considerably less than that in conventional 8 YSZ.This study offers a stepping stone toward utilizing pyrochlore-type LZ7 C3 materials as advanced TBCs at high temperatures.

关键词： Oxygen ion diffusion La 2 (Zr 0.7 Ce 0.3 ) 2 O 7 Pyrochlore structure Thermal barrier coatings

Compressive Performance of Fiber Reinforced Recycled Aggregate Concrete by Basalt Fiber Reinforced Polymer-Polyvinyl Chloride Composite Jackets

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Journal of Renewable Materials 2023年第4期11卷 1763-1791页

作者： Zhijie Fan Huaxin Liu Genjin Liu xuezhi wang Wenqi Cui Civil Engineering&Architecture College Liaoning University of TechnologyJinzhou121001China School of Civil Engineering&Architecture Ningbo Tech UniversityNingbo315100China

The development of recycled aggregate concrete(RAC)provides a new approach to limiting the waste of natural resources.In the present study,the mechanical properties and deformability of RACs were improved by adding basalt fibers(BFs)and using external restraints,such as a fiber-reinforced polymer(FRP)jacket or a PVC pipe.Samples were tested under axial compression.The results showed that RAC(50%replacement of aggregate)containing 0.2%BFs had the best mechanical properties.Using either BFs or PVC reinforcement had a slight effect on the loadbearing capacity and mode of failure.With different levels of BFs,the compressive strengths of the specimens reinforced with 1-layer and 3-layer basalt fiber reinforced polymer(BFRP)increased by 6.7%–10.5%and 16.5%–23.7%,respectively,and the ultimate strains increased by 48.5%–80.7%and 97.1%–141.1%,respectively.The peak stress of the 3-layer BFRP-PVC increased by 42.2%,and the ultimate strain improved by 131.3%,relative to the control.This reinforcement combined the high tensile strength of BFRP,which improved the post-peak behavior,and PVC,which enhanced the structural durability.In addition,to investigate the influence of the various constraints on compressive behavior,the stress-strain response was analyzed.Based on the analysis of experimental results,a peak stress-strain model and an amended ultimate stress-strain model were proposed.The models were verified as well;the result showed that the predictions from calculations are generally consistent with the experimental data(error within 10%).The results of this study provide a theoretical basis and reference for future applications of fiber-reinforced recycled concrete.

关键词： Basalt fiber reinforced polymer polyvinyl chloride recycled aggregate concrete axial compression performance stress-strain relationships stress-strain model

Ultralow oxygen ion diffusivity in pyrochlore-type La_(2)(Zr_(0.7)Ce_(0.3))_(2)O_(7)

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Journal of Materials Science & Technology 2022年第7期 174-185页

作者： Junwei Che Xiangyang Liu xuezhi wang Quan Zhang Erhu Zhang Gongying Liang Shengli Zhang MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Applied Physics School of ScienceChang’an UniversityXi’an 710064China

Thermally grown oxides(TGOs)at the ceramic top-coat/metallic bond-coat interface are a pressing chal-lenge in advanced thermal barrier coating(TBC)systems as they can affect the performance and ser-vice lifetime of TBCs.Thus,developing novel TBC materials with ultralow oxygen ion diffusivity is very urgent.In this study,we reported the diffusive properties of oxygen ions in a novel pyrochlore-type La_(2)(Zr_(0.7)Ce_(0.3))_(2)O_(7)(LZ7C3)material.The measured ionic conductivity and atomistic simulation revealed that the oxygen ion diffusivity in LZ7C3 grains is two orders of magnitude lower than that in conventional 8 wt.%yttria-stabilized zirconia(8YSZ)grains.This is due to the relatively high energy barrier for oxygen hopping in LZ7C3.In addition,it was found that enhancing the order distribution of cations is a strategy to reduce the intrinsic oxygen diffusion of pyrochlore-type oxides.On the other hand,we observed that La^(3+) cations segregate at the grain boundaries(GBs)of LZ7C3,which results in the electrostatic poten-tial at GBs being comparable to that in the bulk.Furthermore,we found that the oxygen ion diffusion is facilitated at the GBs of LZ7C3 due to the stretched O-Zr/Ce bond and the low coordination at GBs.How-ever,the segregations of Y^(3+)cations and the increase in the number of oxygen vacancies resulted in the formation of an electrostatic layer at the GBs of 8YSZ,which shielded the oxygen ion diffusion.Despite this,the oxygen ion diffusivity in LZ7C3 was still considerably less than that in conventional 8YSZ.This study offers a stepping stone toward utilizing pyrochlore-type LZ7C3 materials as advanced TBCs at high temperatures.

关键词： Oxygen ion diffusion La_(2)(Zr_(0.7)Ce_(0.3))_(2)O_(7) Pyrochlore structure Thermal barrier coatings

Nucleon momentum distribution of 56Fe from the axially deformed relativistic mean-field model with nucleon-nucleon correlations

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Science China(Physics,Mechanics & Astronomy) 2021年第9期64卷 29-40页

作者： xuezhi wang Qinglin Niu Jinjuan Zhang Mengjiao Lyu Jian Liu Chang Xu Zhongzhou Ren College of Science China University of Petroleum(East China)Qingdao 266580China College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590China College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Physics Nanjing UniversityNanjing 210093China School of Physics Science and Engineering Tongji UniversityShanghai 200092China

Nucleon momentum distribution(NMD), particularly its high-momentum components, is essential for understanding the nucleonnucleon(NN) correlations in nuclei. Herein, we develop the studies of NMD of 56Fe from the axially deformed relativistic mean-field(RMF) model. Moreover, we introduce the effects of NN correlation into the RMF model from phenomenological models basing on deuteron and nuclear matter. For the region k kF, the high-momentum components of the RMF model are modified by the effects of NN correlation, which agree with the experimental data. Comparing the NMD of relativistic and non-relativistic mean-field models, the relativistic effects on nuclear structures in momentum space are analyzed. Finally, by analogizing the tensor correlations in deuteron and Jastrow-type correlations in nuclear matter, the behaviors and contributions of NN correlations in 56Fe are further analyzed, which helps clarify the effects of the tensor force on the NMD of heavy nuclei.

关键词： nucleon momentum distribution deformed relativistic mean-field model nucleon-nucleon correlations

Bond Behavior between BFRP Bars and Hybrid Fiber Recycled Aggregate Concrete after High Temperature

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Journal of Renewable Materials 2021年第3期9卷 507-521页

作者： Boheng Zhu Huaxin Liu Genjin Liu Abasal Hussain Xiaofei Zhang xuezhi wang College of Civil and Architectural Engineering Liaoning University of TechnologyJinzhou121000China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian116024China Institute of Water Resources and Hydro-electric Engineering Xi’an University of TechnologyXi’an710048China

The aim of this study is to improve the bond performance of basalt fiber reinforced polymer(BFRP)bars and recycled aggregate concrete(RAC)after being exposed to high temperatures.The bond behavior(failure modes,bond strength,bond stress-slip curves)between BFRP bars and hybrid fiber recycled aggregate concrete(HFRAC)after being exposed to temperatures ranging from 20℃up to 500℃was studied by using pull-out tests.The effect of high temperatures on mechanical properties of concrete(compressive strength,splitting tensile strength)and tensile strength of BFRP bars was also investigated.The bond strength decreased as the temperature increased and the drop of bond strength between RAC and BFRP bar was larger than that between HFRAC and BFRP bar.As the temperature rises,the key factor affecting the bond strength was gradually transformed from concrete strength to BFRP bar strength.The relationship between bond stress and slip in the dimensionless bond stress-slip ascending section was established,which was in good agreement with the experimental results.

关键词： High temperature BFRP bar hybrid fiber recycled aggregate concrete bond performance

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氧化石墨烯复掺纤维水泥基复合材料研究综述

功能材料 2024年第3期55卷 3073-3082页

作者：韩雷莹王学志辛明王思月贺晶晶辽宁工业大学土木建筑工程学院辽宁锦州121001 南京交通技师学院南京210000 中国电建集团西北勘测设计研究院有限公司西安710065

氧化石墨烯(GO)作为石墨烯(G)的衍生物有着与石墨烯相类似的力学性能和导热性能等优异性能,并且其亲水性官能团使其相比于石墨烯来说更容易在水中分散从而更容易与水泥基相结合。大量研究已表明GO掺入水泥基中不但可以增强水泥基的力学... 详细信息

氧化石墨烯(GO)作为石墨烯(G)的衍生物有着与石墨烯相类似的力学性能和导热性能等优异性能,并且其亲水性官能团使其相比于石墨烯来说更容易在水中分散从而更容易与水泥基相结合。大量研究已表明GO掺入水泥基中不但可以增强水泥基的力学性能和耐久性能还可以增强水泥基的电磁屏蔽性能、导热性能等性能,为多功能型、智能型混凝土的开发提供了可能。以GO复掺其他功能纤维材料在水泥基中的应用为中心,简述了GO的性能特点、结构特质从而表明GO在水泥基材料中应用的广度和范围,并重点综述了GO的分散性研究和GO复掺纤维水泥基的工作性能、水化过程、力学性能、耐久性能、功能性能的研究,并对未来GO复掺纤维水泥基材料研究的方向进行了展望。

关键词：水泥基复合材料氧化石墨烯耐久性导热电

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大规模开放遥感影像地图渲染与缓存优化

计算机工程 2024年第7期50卷 227-239页

作者：周小华周园春孟珍王学志中国科学院计算机网络信息中心北京100083 中国科学院大学北京100049

遥感数据规模庞大且增长迅速,目前可公开访问的遥感影像数据已接近EB级别,然而类型多样、结构复杂、存储文件大等特点给大规模开放遥感数据的发现、共享与使用带来诸多不便。在线地图可使用户无须下载便可对海量云端遥感数据执行可视化... 详细信息

遥感数据规模庞大且增长迅速,目前可公开访问的遥感影像数据已接近EB级别,然而类型多样、结构复杂、存储文件大等特点给大规模开放遥感数据的发现、共享与使用带来诸多不便。在线地图可使用户无须下载便可对海量云端遥感数据执行可视化分析,是一种高效的数据服务方式。针对传统地图技术方案存在的瓦片渲染效率低、遥感数据适配性差等问题,从遥感数据时空属性特征及用户访问行为特征出发,依托遥感数据云平台GSCloud,设计并实现面向海量遥感数据的高效地图服务平台TiMap。TiMap由分布式地图瓦片渲染引擎TiRender与分布式地图瓦片缓存TiCache构成。TiRender通过将地图瓦片渲染操作转换为分布式环境下的同步实时渲染任务与异步批量预渲染任务,充分利用多节点并行计算的优势,快速响应客户端的地图瓦片请求。TiCache负责缓存TiRender产生的地图瓦片,以提升后续重复地图瓦片请求的响应速度,TiCache中的地图瓦片缓存分配算法基于疏远度实现,可以保证多节点的负载均衡。实验结果表明,TiRender与TiCache均比同类技术方案的性能更好,两者协同工作可使TiMap在100ms内快速响应大规模地图瓦片请求。

关键词：遥感大数据遥感地图服务地图瓦片渲染地图瓦片缓存数据疏远度

Photo-catalytic Staphylococcus aureus inactivation and biofilm destruction with novel bis-tridentate iridium(Ⅲ) photocatalyst

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Chinese Chemical Letters 2023年第11期34卷 191-194页

作者： Shihao Chen Zhishang Zhang Li Wei Zhongxian Fan Yue Li xuezhi wang Tongming Feng Huaiyi Huang The Fourth People’s Hospital of Foshan Foshan 528000China School of Pharmaceutical Science(Shenzhen) Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Bacterial infection is currently a serious challenge globally, causing death of thousands of human beings. New antimicrobial agents with novel mechanism of action are urgently needed. Transition metal complexes have shown great potentials in photodynamic and photocatalytic therapy. Herein, we take full advantage of metal photocatalyst and successfully developed a novel cyclometalated iridium(Ⅲ) complex(Ir1) with higher biofilm damage efficiency than the clinical antibiotics. Ir1 synergistically generates reactive oxygen species and coenzyme photocatalytic activity with high efficiency under white light irradiation. Combined with these properties, Ir1 exhibited excellent photoinactivation of S. aureus and effectively damaged the biofilm. This work provides a new approach for the development of antibacterial photodynamic therapy.

关键词： Ir(Ⅲ)photocatalyst NADH depletion Reactive oxygen species Antimicrobial photocatalytic therapy