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Understanding the Moon's internal structure through moonquake observations and remote sensing technologies

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Science China Earth Sciences 2018年第8期61卷 995-1006页

作者： weifeng hao Fei LI Chi XIAO Jianguo YAN Mao YE Chinese Antarctic Center of Surveying and Mapping Wuhan University State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University

Explorations for the interior structure of the Moon mainly involve three technologies: the early gravitational observations via circumlunar satellites, the moonquake observations during the Apollo period, and the recent high-resolution remote sensing observations. Based on these technologies, we divided the development of the moon's interior structure into three stages. The first stage is the discovery of high-density anomalous masses(mascons) on the lunar surface with the low-order gravitational field models, which were obtained by observing perturbations of the early lunar orbital satellites. The second stage is the preliminary understanding of the layer structure with the help of moonquake observations during the Apollo period. The third stage is the deep understanding of the structure of the lunar crust, mantle, and core, with the use of high-resolution remote sensing data and the reassessment of moonquake data from the Apollo's mission. This paper gave detailed introduction and comments on different observation technologies, gathered data, and data processing techniques used at the three stages. In addition, this paper analyzed the current issues in the researches on the Moon's internal structure and discussed the prospects for future explorations.

关键词： Moon Mascon Moonquake Remote sensing Lunar internal structure

Evaluation of the glacial isostatic adjustment(GIA) models for Antarctica based on GPS vertical velocities

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Science China Earth Sciences 2020年第4期63卷 575-590页

作者： Fei LI Chao MA Shengkai ZHANG Jintao LEI weifeng hao Qingchuan ZHANG Wenhao LI Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China

Due to the scarcity of data, modeling the glacial isostatic adjustment(GIA) for Antarctica is more difficult than it is for the ancient ice sheet area in North America and Northern Europe. Large uncertainties are observed in existing GIA models for Antarctica. Modern space-based geodetic measurements provide checks and constraints for GIA models. The present-day uplift velocities of global positioning system(GPS) stations at 73 stations in Antarctica and adjacent regions from 1996 to 2014 have been estimated using GAMIT/GLOBK version 10.5 with a colored noise model. To easily analyze the effect of difference sources on the vertical velocities, and for easy comparison with both GIA model predictions and GPS results from Argus et al.(2014) and Thomas et al.(2011), seven sub-regions are divided. They are the northern Antarctic Peninsula, the Filchner-Ronne Ice Shelf, the Amundsen Sea coast, the Ross Ice Shelf, Mount Erebus, inland Southwest Antarctica and the East Antarctic coast,respectively. The results show that the fast uplift in the north Antarctic Peninsula and Pine Island Bay regions may be caused by the elastic response to snow and ice mass loss. The fast subsidence near Mount Erebus may be related to the activity of a magma body. The uplift or subsidence near the East Antarctic coast is very slow while the uplift for the rest regions is mainly caused by GIA. By analyzing the correlation and the associated weighted root mean square(WRMS) between the GIA predictions and the GPS velocities, we found that the ICE-6G_C(VM5a) model and the Geruo 13 model show the most consistency with our GPS results, while the W12a and IJ05_R2 series models show poor consistency with our GPS results. Although improved greatly in recent years, the GIA modeling in Antarctica still lags behind the modeling of the North American. Some GPS stations, for example the Bennett Nunatak station(BENN), have observed large discrepancies between GIA predictions and GPS *** of the

关键词： Antarctica GPS Glacial isostatic adjustment Vertical velocity Uncertainty

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利用固体潮研究岩石天体的深部结构

地球与行星物理论评（中英文） 2024年第5期55卷 537-551页

作者：肖驰李斐鄢建国叶茂原田雄司郝卫峰邓青云中国地震局地震研究所地震大地测量重点实验室武汉430071 武汉引力与固体潮国家野外科学观测研究站武汉430071 武汉大学测绘遥感信息工程国家重点实验室武汉430079 武汉大学中国南极测绘研究中心武汉430079 澳门科技大学创新工程学院中国澳门999078

经过地球物理学的长足发展,我们有着丰富的手段来研究地球的内部结构.然而对于地球之外的其他天体,研究其内部结构的手段却仍然十分有限,往往依赖于轨道探测器、着陆器以及天文观测获取的大地测量数据.在这之中,固体潮对研究其内部结构... 详细信息

经过地球物理学的长足发展,我们有着丰富的手段来研究地球的内部结构.然而对于地球之外的其他天体,研究其内部结构的手段却仍然十分有限,往往依赖于轨道探测器、着陆器以及天文观测获取的大地测量数据.在这之中,固体潮对研究其内部结构有着重要的意义.固体潮汐形变和其带来的潮汐耗散提供了关于行星内部结构,尤其是深部核幔边界及核心部分的关键信息.本文将全面地对利用固体潮汐参数(包括潮汐勒夫数及潮汐品质因子)研究岩石天体的深部结构进行综述.首先对固体潮的基本理论、潮汐参数以及黏弹性模型进行了介绍,建立了天体内部结构参数与其外部固体潮汐响应之间的关系.之后对现有利用固体潮汐参数研究水星、金星、火星及月球这些岩石天体的内部结构的工作进行了回顾与总结,可以发现固体潮汐参数是一种对天体深部结构进行约束的有效手段.本文进一步提供了未来探测任务获取的高精度数据对研究天体深部结构的贡献.然而,目前固体潮汐参数对天体深部结构研究中也存在一些问题.例如不同黏弹性模型之间耗散强度的差异性问题、黏弹性模型的短周期实验数据和宏观长周期理论计算结果之间的不匹配问题等.本文也针对这些问题进行了讨论和分析,并对未来的研究方向进行了展望.

关键词：固体潮潮汐响应黏弹性内部结构岩石天体

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月幔底部黏弹性结构研究现状

中国科学：物理学、力学、天文学 2024年第3期54卷 19-29页

作者：肖驰叶茂李斐鄢建国 Yuji Harada 郝卫峰邓青云中国地震局地震研究所地震大地测量重点实验室武汉430071 武汉引力与固体潮国家野外科学观测研究站武汉430071 武汉大学测绘遥感信息工程国家重点实验室武汉430079 武汉大学中国南极测绘研究中心武汉430079 澳门科技大学创新工程学院中国澳门999078

长期以来,月球幔层底部是否存在一个部分熔融的S波衰减层一直存在着争议.针对这一争议,本文首先回顾了国内外对月幔底部黏弹性结构的研究成果,梳理总结了争议的提出和发展历程,接着分析这一争议产生的主要原因.本文认为,虽然越来越多的... 详细信息

长期以来,月球幔层底部是否存在一个部分熔融的S波衰减层一直存在着争议.针对这一争议,本文首先回顾了国内外对月幔底部黏弹性结构的研究成果,梳理总结了争议的提出和发展历程,接着分析这一争议产生的主要原因.本文认为,虽然越来越多的研究支持月幔底部存在一个部分熔融的低黏性、低S波波速的转换层,但目前仍缺乏决定性的证据作为支撑.因此,本文进一步讨论了现有研究存在的不足,对未来研究方向进行了展望.

关键词：月球固体潮潮汐勒夫数黏弹性模型内部结构

MIR1868 negatively regulates rice cold tolerance at both the seedling and booting stages

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The Crop Journal 2024年第2期12卷 375-383页

作者： Yang Shen Xiaoxi Cai Yan Wang Wanhong Li Dongpeng Li hao Wu weifeng Dong Bowei Jia Mingzhe Sun Xiaoli Sun Crop Stress Molecular Biology Laboratory Heilongjiang Bayi Agricultural UniversityDaqing 163319HeilongjiangChina

Low temperature causes rice yield losses of up to 30%–40%,therefore increasing its cold tolerance is a breeding *** genes in rice are reported to confer cold tolerance at both the vegetative and reproductive *** study revealed a rice-specific 24-nt miRNA,miR1868,whose accumulation was suppressed by cold *** of MIR1868 increased seedling survival,pollen fertility,seed setting,and grain yield under cold stress,whereas its overexpression conferred the opposite *** of MIR1868 increased reactive oxygen species(ROS)scavenging and soluble sugar content under cold stress by increasing the expression of peroxidase genes and sugar metabolism genes,and its overexpression produced the opposite ***,MIR1868 negatively regulated rice cold tolerance via ROS scavenging and sugar accumulation.

关键词： Rice Cold tolerance miRNA ROS scavenging Soluble sugar accumulation

Heteroatom Structural Engineering Enables Ethenylene-Bridged Bisisoindigo-Based Copolymers to Exhibit Unique n-Type Transistor Performance

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CCS Chemistry 2024年第2期6卷 473-486页

作者： Yuchai Pan weifeng Zhang Yankai Zhou Xuyang Wei hao Luo Jinbei Wei Liping Wang Gui Yu Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190 School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049 School of Material Science and Engineering University of Science and Technology BeijingBeijing 100083

Herein,we report three novel electron-deficient aromatics,ethenylene-bridged bisisoindigos 3,3′-((3E,3′E)-((E)-ethene-1,2-diyl)bis(1-(4-decyltetradecyl)-2-oxoind-oline-6-yl-3-ylidene))bis(1-(4-decyltetradecyl)-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one)(NCCN),3,3′-((3E,3′E)-((E)-ethene-1,2-diyl)bis(1-(4-decyltetradecyl)-7-fluoro-2-oxoindoline-6-yl-3-ylidene))bis(1-(4-decyltetradecyl)-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one)(NFFN),and(3E,3″E)-6,6″-((E)-ethene-1,2-diyl)bis(1,1′-bis(4-decyltetradecyl)-[3,3′-bipyrrolo[2,3-b]pyridinylidene]-2,2′(1H,1′H)-dione)(NNNN),and their derived donor–acceptor(D–A)copolymers,namely poly[3,3′-((3E,3′E)-((E)-ethene-1,2-diyl)bis(1-(4-decyltetradecyl)-2-oxoindoline-6-yl-3-ylidene))bis(1-(4-decyltetradecyl)-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one-6-yl)]-alt-[5,6-difluoro-4,7-di[(thiophen-2-yl)-5-yl)]benzo[c][1,2,5]thiadiazole](PNCCN-FBT),poly[3,3′-((3E,3′E)-((E)-ethene-1,2-diyl)bis(1-(4-decyltetradecyl)-7-fluoro-2-oxoindoline-6-yl-3-ylidene))bis(1-(4-decyltetradecyl)-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one-6-yl)]-alt-[5,6-difluoro-4,7-di[(thiophen-2-yl)-5-yl)]benzo[c][1,2,5]thiadiazole](PNFFNFBT),and poly[(3E,3″E)-6′,6‴-((E)-ethene-1,2-diyl)bis(1,1′-bis(4-decyltetradecyl)-[3,3′-bipyrrolo[2,3-b]pyridinylidene]-2,2′(1H,1′H)-dione-6-yl)]-alt-[5,6-difluoro-4,7-di[(thiophen-2-yl)-5-yl)]benzo[c][1,2,5]thiadiazole](PNNNN-FBT),in which 5,6-difluoro-4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole(FBT)acts as the electron-donating *** ethenylene-bridging unit reduces the steric hindrance of the three *** of heteroatoms,such as fluorine and sp2-nitrogen atoms,endows them with multiple CH···F,CH···N,and N···S intramolecular hydrogen bonds/nonbinding interactions,resulting in increasing backbone planarity from NCCN,NFFN,to NNNN,and thus from PNCCN-FBT,PNFFN-FBT,to *** found that all copolymers formed an improved molecular packing in the 1-chloronaphthalene(CN)-processed thin film compared with the 1,2-d

关键词： D-A copolymers bisisoindigos heteroatom structural engineering n-type field-effect transistors electron mobilities

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月球和地球正常重力特征差异及成因探讨

地球物理学报 2021年第7期64卷 2417-2425页

作者：郝卫峰叶茂鄢建国李斐武汉大学中国南极测绘研究中心武汉430079 武汉大学测绘遥感信息工程国家重点实验室武汉430079

月球和地球都非常接近于旋转椭球,基于正常椭球求定的正常重力场占据了月球和地球真实重力场的主要部分,比较月球和地球的正常重力,可以更好地理解这两个天体的重力变化特征.基于Clairaut定理求解月球和地球的正常重力,正常重力随纬度... 详细信息

月球和地球都非常接近于旋转椭球,基于正常椭球求定的正常重力场占据了月球和地球真实重力场的主要部分,比较月球和地球的正常重力,可以更好地理解这两个天体的重力变化特征.基于Clairaut定理求解月球和地球的正常重力,正常重力随纬度的变化呈现了相反趋势,即地球是两极的正常重力大于赤道的正常重力,而月球是两极的正常重力小于赤道的正常重力.从截断误差及椭球形状与自转角速度的协调关系分析了月球和地球正常重力随纬度变化产生相反趋势的原因:月球的椭球扁率与自转角速度之间的数值关系不满足行星流体静力学平衡条件,即利用Clairaut定理求解正常重力并不严格适用于月球.

关键词：正常重力地球月球反趋势流体静力学平衡条件

Thermal conductivity of GeTe crystals based on machine learning potentials

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Chinese Physics B 2024年第4期33卷 104-107页

作者：张健张昊春李伟峰张刚 School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Institute of High Performance Computing Agency for ScienceTechnology and ResearchSingapore 138632Singapore School of Physics&State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China

GeTe has attracted extensive research interest for thermoelectric *** this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussian approximation potential(GAP)as a *** phonon density of states is then calculated by two machine learning potentials and compared with density functional theory results,with the GAP potential having higher ***,the thermal conductivity of a GeTe crystal at 300 K is calculated by the equilibrium molecular dynamics method using both machine learning potentials,and both of them are in good agreement with the experimental results;however,the calculation speed when using the NEP potential is about 500 times faster than when using the GAP ***,the lattice thermal conductivity in the range of 300 K-600 K is calculated using the NEP *** lattice thermal conductivity decreases as the temperature increases due to the phonon anharmonic *** study provides a theoretical tool for the study of the thermal conductivity of GeTe.

关键词： machine learning potentials thermal conductivity molecular dynamics

格陵兰地区GLASS反照率产品质量评价及反照率变化趋势分析

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武汉大学学报（信息科学版） 2022年第11期47卷 1917-1926页

作者：马超郝卫峰程青罗杰李斐武汉大学中国南极测绘研究中心湖北武汉430079 武汉大学自然资源部极地测绘科学重点实验室湖北武汉430079 中国地质大学(武汉)计算机学院湖北武汉430074

冰雪反照率是影响和评估全球气候变化的重要因子。北极格陵兰岛拥有世界第二大冰盖,定量获取该地区反照率是研究北半球能量收支变化的关键。全球陆表卫星(global land surface satellite,GLASS)产品系统生产的反照率产品是目前国际上时... 详细信息

冰雪反照率是影响和评估全球气候变化的重要因子。北极格陵兰岛拥有世界第二大冰盖,定量获取该地区反照率是研究北半球能量收支变化的关键。全球陆表卫星(global land surface satellite,GLASS)产品系统生产的反照率产品是目前国际上时间序列最长(1981—2017年)的全球反照率产品。利用格陵兰气候观测网络(Greenland climate network,GC-Net)与格陵兰冰架监测计划(programme for monitoring of the Greenland ice sheet,PROMICE)网络观测的反照率数据,评估了格陵兰地区GLASS地表反照率产品的精度;并基于2000—2017年的GLASS地表反照率产品,分析了格陵兰地区7月份反照率的年际变化趋势与空间分布特征。结果表明:GLASS与GC-Net反照率的均方根误差(root mean squared error,RMSE)为0.0778(决定系数R2=0.4907),与PROMICE反照率差异的RMSE为0.0786(R2=0.8999),GLASS产品的反照率数值呈现一定的低估现象,但已满足格陵兰地区冰雪反照率研究的需要。基于2000—2017年7月份格陵兰地区的GLASS反照率变化分析可以看出,格陵兰地区的反照率在此期间整体呈现变小的趋势,平均速率约为0.0006/a,变小的地区约占格陵兰总面积的64%;其中,位于格陵兰西部海拔750~1500 m之间的区域对气候变化最为敏感,反照率变小速率也最大,达到了0.026/a。

关键词：格陵兰冰盖冰雪反照率 GLASS反照率产品质量评估年际变化