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science China(Technological sciences) 2011年第6期54卷 1445-1454页

作者： ZHAO Hong ZONG QiuGang WEI Yong wang YongFu Institute of space Physics and applied Technology Peking University Beijing 100871 China center for Atmospheric research University of Massachusetts Lowell MA 01854-3629 USA

The Dst index,designed as a proxy of ring current intensity,is known to be also affected by other magnetospheric current systems,*** *** pressure-corrected Dst index is obtained by removing the effects of the solar wind dynamic pressure and the quiet time ring ***,all previous studies treated the correction coefficient as an averaged parameter for storms of different *** this paper,based on the Burton's equations and employing two independent methods,we will show a positive correlation between pressure-correction coefficient b and the intensity of the *** divided our storm database(872.storms in total) into three categories according to the intensity of *** order to improve the accuracy of calculating,we also used the higher-resolution SYM-H index data instead of Dst index to compute the corrected Dst index during different ***,we are able to provide corrected magnetic storm index with high-time resolution(-1 min).

关键词： corrected Dst index pressure correction geomagnetic storms with different intensity

Displacement damage dose used for analyzing electron irradiation-induced degradation of GaInP/GaAs/Ge space solar cells

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science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 296-299页

作者： wang Rong LU Ming LIU YunHong FENG Zhao Key Laboratory of Beam Technology and Materials Modification of Ministry of Education Beijing Normal UniversityBeijing 100875China College of Nuclear science and Technology Beijing Normal UniversityBeijing 100875China beijing Radiation center Beijing 100875China

Displacement damage dose (Dd) approach was applied to analyze the electron irradiation-induced degradation of GaInP/ GaAs/Ge space solar cells by effective 1 MeV electron Dd, the electron irradiation-induced maximum power Pmax degradation of the solar cells is plotted as a function of the effective 1 MeV electron Dd , and the result shows that all the measured electron data can be represented by a single curve using displacement damage dose. Obviously, the displacement damage dose approach simplifies the description of electron irradiation-induced degradation of GaInP/GaAs/Ge space solar cells, and also offers an alternative for handling the case where degradation occurs as a result of combined electron and proton irradiation.

关键词： GaInP/GaAs/Ge solar cells displacement damage dose non-ionizing energy loss electron irradiation

Analysis of the Distribution,Rotation and Scale Characteristics of Solar Wind Switchbacks:Comparison between the First and Second Encounters of Parker Solar Probe

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research in Astronomy and Astrophysics 2022年第3期22卷 178-185页

作者： Ming-Ming Meng Ying D.Liu Chong Chen Rui wang State Key Laboratory of space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of chinese academy of {2.s Beijing 100049China

The S-shaped magnetic structure in the solar wind formed by the twisting of magnetic field lines is called a switchback,whose main characteristics are the reversal of the magnetic field and the significant increase in the solar wind radial *** identify 2.2.switchbacks during the first two encounters of Parker Solar *** methods are applied to analyze the distribution and the rotation angle and direction of the magnetic field rotation of the *** diameter of switchbacks is estimated with a minimum variance analysis(MVA)method based on the assumption of a cylindrical magnetic *** also make a comparison between switchbacks from inside and the boundary of coronal *** main conclusions are as follows:(1)the rotation angles of switchbacks observed during the first encounter seem larger than those of the switchbacks observed during the second encounter in general;(2.the tangential component of the velocity inside the switchbacks tends to be more positive(westward)than in the ambient solar wind;(3.switchbacks are more likely to rotate clockwise than counterclockwise,and the number of switchbacks with clockwise rotation is 1.48 and 2.65 times those with counterclockwise rotation during the first and second encounters,respectively;(4)the diameter of switchbacks is about 10;km on average and across five orders of magnitude(10^(3.–10^(7)km).

关键词： ISM:magnetic fields methods:statistical (Sun:)solar wind

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全球典型热带雨林的微波散射特征建模与验证

应用气象学报 2024年第3期35卷 350-360页

作者：王一同胡秀清商建顾玲嘉尹红刚中国气象科学研究院北京100081 国家卫星气象中心/国家空间天气监测预警中心北京100081 许健民气象卫星创新中心北京100081 中国气象局中国遥感卫星辐射测量和定标重点开放实验室北京100081 吉林大学长春130012

使用大面积且均匀的自然目标进行微波散射计的定标检验,有助于客观评价微波遥感的观测精度。热带雨林具有相对稳定的植被覆盖条件,可减小地表异质性对仪器测量的影响,是微波仪器定标评价的常用目标。利用2.19年1月1日—2.2.年12.3.日Me... 详细信息

使用大面积且均匀的自然目标进行微波散射计的定标检验,有助于客观评价微波遥感的观测精度。热带雨林具有相对稳定的植被覆盖条件,可减小地表异质性对仪器测量的影响,是微波仪器定标评价的常用目标。利用2.19年1月1日—2.2.年12.3.日Met Op-B(the second meteorological operational satellite)卫星ASCAT(advanced scatterometer)散射计的观测数据,提出平均值、标准差与相对标准差联合的雨林目标稳定区优选算法,确定亚马逊雨林、刚果雨林和东南亚雨林的稳定区域,对稳定区内目标的自身特性开展包括季节、入射角和方位角影响建模。建模时综合考虑模型误差和时序变化,将目标特性与仪器波动导致的后向散射系数变化分离。结果表明:亚马逊雨林和刚果雨林稳定区的白天数据具有较低的模型误差和波动较小的变化趋势,适用于多星散射计的定标稳定性检验。基于亚马逊雨林和刚果雨林稳定区的白天数据模型,对Met Op-C卫星的ASCAT观测数据进行定标稳定性检验和分析,检验结果表明:Met Op-C卫星ASCAT散射计的观测数据略有波动,但变化幅度小于0.05 d B,定标稳定性较好。

关键词：散射计热带雨林稳定区优选特征建模定标检验

Fengyun Satellites:Achievements and Future

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空间科学学报 2010年第5期30卷 468-473页

作者： wang Jingsong Zhang Jiashen Tang Yunqiu National Satellite Meteorological center/National center for {2. Weather China Meteorological Administration Beijing 100081

chinese meteorological satellite,Fengyun(FY) Satellite,has a polar-orbiting series and a geostationary *** to now,5 polar-orbiting(FY-1A/B/C/D and FY-3.) and 5 geostationary(FY-2./B/C/D/E) satellites were *** data has been being intensively applied not only to meteorological monitoring and prediction but also to many other fields regarding ecology,environment,disaster,{2. weather and so *** FY data sharing system,FengyunCast,is now one of the three components of global meteorological satellite information dissemination system,*** first satellite of the new generation polar-orbiting series,FY-3.,was launched on 2. May,2.08,demonstrating the FY polar-orbiting satellite and its application completed a great leap to realize threedimensional observations and quantitative *** first of the next generation geostationary series(FY-4) is planned to launch in 2.14.

关键词：气象卫星卫星发射数据共享系统信息传播系统极地轨道气象监测空间天气组成部分

A method of estimating the Martian neutral atmospheric density at 13. km, and comparison of its results with Mars Global Surveyor and Mars Odyssey aerobraking observations based on the Mars Climate Database outputs

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Earth and Planetary Physics 2020年第4期4卷 408-419页

作者： JunFeng Qin Hong Zou YuGuang Ye YongQiang Hao JinSong wang Erling Nielsen Institute of space Physics and applied Technology School of Earth and Space SciencePeking UniversityBeijing 100871China National center for space Weather China Meteorological AdministrationBeijing 100081China Max Planck Institute for Solar System research Katlenburg-Lindau 37191Germany

Profiles of the Martian dayside ionosphere can be used to derive the neutral atmospheric densities at 13. km,which can also be obtained from the Mars Climate Database(MCD)and spacecraft aerobraking *** this research,we explain the method used to calculate neutral densities at 13. km via ionosphere observations and three long-period 13.-km neutral density data sets at northern high latitudes(latitudes>60°)acquired through ionospheric data measured by the Mars Global Surveyor(MGS)Radio Occultation *** calculated 13.-km neutral density data,along with 13.-km density data from the aerobraking observations of the MGS and Mars Odyssey(ODY)in the northern high latitudes,were compared with MCD outputs at the same latitude,longitude,altitude,solar latitude,and local *** 13.-km density data derived from both the ionospheric profiles and aerobraking observations were found to show seasonal variations similar to those in the MCD *** a negative shift of about 2.10^10 cm^−3.the corrected 13.-km neutral densities derived from MCD v4.3.were consistent with those obtained from the two different *** result means that(1)the method used to derive the 13.-km neutral densities with ionospheric profiles was effective,(2.the MCD v4.3.data sets generally overestimated the 13.-km neutral densities at high latitudes,and(3.the neutral density observations from the MGS Radio {2. Experiment could be used to calibrate a new atmospheric model of Mars.

关键词： Martian upper atmosphere Mars Climate Database v4.3 aerobraking observations Mars global circulation

An Improved HVQ Algorithm for Compression and Rendering of space Environment Volume Data with Multi-correlated Variables

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空间科学学报 2023年第4期43卷 780-785页

作者： BAO Lili CAI Yanxia wang Rui ZOU Yenan SHI Liqin State Key Laboratory of space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 Key Laboratory of science and Technology on Environmental space Situation Awareness Chinese Academy of SciencesBeijing 100190 University of chinese academy of {2.s Beijing 100049

Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment *** environment simulation can produce several correlated variables at the same ***,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these *** space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these *** volume data associated with each variable is divided into disjoint blocks of size 43.*** blocks are represented as two levels,a mean level and a detail *** variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail *** both global levels,a splitting based on a principal component analysis is {2. to compute initial ***,LBG algorithm is conducted for codebook refinement and *** further take advantage of progressive rendering based on GPU for real-time interactive *** method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>3. and>50 MeV integrated proton *** results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.

关键词： Compressed volume rendering Multi-correlated variables space environment Vector quantization GPU programming

Tianwen-1 MINPA observations in the solar wind

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Earth and Planetary Physics 2022年第1期6卷 1-9页

作者： AiBing Zhang LingGao Kong WenYa Li Lei Li BinBin Tang ZhaoJin Rong Yong Wei JiJie Ma YiTeng Zhang LiangHai Xie YuXian wang JianSen He Bin Liu WenJing wang Bin Su JiaWei Li Xu Tan Fang wang TaiFeng Jin FuHao Qiao Peter Wurz Yan Zhu YunFei Bai YiRen Li XinBo Zhu YueQiang Sun YongLiao Zou Chi wang National space science {2. Chinese Academy of SciencesBeijing 100190China beijing Key Laboratory of space Environment Exploration Beijing 100190China Key Laboratory of science and Technology on space Environment Situational Awareness Chinese Academy of SciencesBeijing 100190China University of chinese academy of {2.s Beijing 100049China State Key Laboratory of space Weather Chinese Academy of SciencesBeijing 100190China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institute of space Physics and applied Technology Peking UniversityBeijing 100871China Lunar Exploration and space Engineering center Beijing 100190China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Physics Institute University of BernBern 3012Switzerland University of science and Technology of China Hefei 230026China Shanghai academy of spaceflight Technology Shanghai 201109China

The Mars Ion and Neutral Particle Analyzer(MINPA)is one of the three scientific instruments onboard the Tianwen-1 orbiter to investigate the Martian space *** Tianwen-1’s transfer orbit to Mars,the MINPA was switched on to measure the solar wind ***,we present the first results of the MINPA observations in the solar *** cruise,nearly half of the MINPA ion field-of-view(FOV)was blocked by the lander capsule;thus only the solar-wind ions with azimuthal speeds pointing towards the unblocked FOV sectors could be *** perform a detailed comparison of the MINPA’s solar wind observations with data from Earth-based missions when MINPA reached its count-rate peak,finding a general consistency of the ion moments between *** blocking effect due to the lander is evaluated quantitatively under varying solar-wind velocity *** the blocking effect,the MINPA’s solar wind measurements during the transfer orbit suggest a good performance.

关键词： MINPA Tianwen-1 solar wind capsule blocking effect

Catalytic performance of Nb2.5 modified Ru/CeO2.for dichloromethane oxidation

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Progress in Natural science:Materials International 2023年第4期33卷 486-494页

作者： Wencheng Hao Zhiwei wang Shaohua Xie Lu Wei Zhiquan Hou Yuxi Liu Hongxing Dai Jiguang Deng beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and Life Beijing University of Technology Department of Civil Environmental and Construction Engineering Catalysis Cluster for Renewable Energy and Chemical Transformations(REACT) Nano Science Technology Center(NSTC) University of Central Florida

1 wt% Ru/5 wt% Nb2.5/CeO2.RuNbCe) catalyst was synthesized via the incipient wetness impregnation method, and measured for the catalytic oxidation of dichloromethane(DCM). The physicochemical properties of catalysts were determined used various characterization techniques. Compared with 1 wt% Ru/CeO2. 5 wt%Nb2.5/CeO2. CeO2. 1 wt% Ru/xNb2.5/CeO2.x = 1 wt%, 2.wt%, and 3.wt%) and 1 wt% Ru/yMOn/CeO2.M =Co, Cr, Fe, Mg, Cu; y = 5 wt%), the addition of 5 wt% Nb2.5obviously improved the catalytic performance of 1 wt% Ru/CeO2. with the T90%and apparent activation energy(Ea) being 2.7℃ and 43.5 kJ/mol, respectively, and less formation of polychlorinated byproducts at {13. velocity(SV) = 15,000 mL g-1h-1. The RuNbCe catalyst showed good thermal and hydrothermal stability, as well as HCl-resistance performance. We deduced that the higher oxidation performance of the RuNbCe catalyst may be attributed to the suitable acidic sites, good redox capacity, high surface adsorbed oxygen species concentration, and the strong interaction among Ru, Nb2.5and CeO2. The RuNbCe catalyst has the potential to be applied for the elimination of chlorinated volatile organic compounds(CVOCs).

关键词： Ru/Nb2.5/CeO2 dichloromethane oxidation Catalytic stability Acidic sites CVOCs removal