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Study of factors influencing the occurrence rate of 60 Hz power line radiation in the topside ionosphere: A systematic survey using the CSES satellite

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Science China Technological Sciences 2024年第6期67卷 1879-1892页

作者： MA ZhenHui ZHAO ShuFan LIAO Li SHEN XuHui LU HengXin School of Emergency Management Science and Engineering University of Chinese Academy of Sciences State key laboratory of Space Weather National Space Science CenterChinese Academy of Sciences key laboratory of solar activity and Space Weather National Space Science CenterChinese Academy of Sciences National Institute of Natural Hazards Ministry of Emergency Management of China Institute of Geophysics China Earthquake Administration

We analyze the topside ionosphere power line radiation（PLR） at 60 Hz over the US using electric field data collected by CSES satellite between January 2019 and December 2022. The study aimed to further investigate the month-to-month variation characteristic of PLR occurrence rate observed by satellite and its several influencing factors, including solar radiation, lightning activity, and try to clarify the influence of electricity consumption. The results show that the solar radiation(solar zenith angle and F10.7) plays a major role in the variation of the PLR occurrence rate, and that there is no direct connection with the number of lightning. For the relationship between PLR occurrence rate and electricity consumption, the low occurrence rate associated with decreased weekend electricity consumption was not observed in the US. However, there is a significant difference in PLR occurrence rate between the East and West Coasts of the US at the same latitude during the same time period, suggesting that the significant difference in PLR occurrence rate is caused by the significant difference in electricity consumption between the two coasts. After excluding the effect of solar radiation on PLR occurrence rate, we concluded that only a significant difference in regional electricity consumption could lead to a corresponding change in PLR occurrence rate detected by the Low-Earth-Orbit satellite. Finally, we also found there is seasonal variation in the diurnal differences of the PLR occurrence rate caused by seasonal variation of the lower ionosphere.

关键词： CSES satellite power line radiation occurrence rate solar radiation lightning activity electricity consumption

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Analysis of the joint detection capability of the SMILE satellite and EISCAT-3D radar

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Earth and Planetary Physics 2024年第1期8卷 299-306页

作者： JiaoJiao Zhang TianRan Sun XiZheng Yu DaLin Li Hang Li JiaQi Guo ZongHua Ding Tao Chen Jian Wu Chi Wang State key laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China key laboratory of solar activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 101408China key laboratory of Electronics and Information Technology for Space Systems Chinese Academy of SciencesBeijing 100190China China Research Institute of Radio-wave Propagation Qingdao 266075China

The solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite is a small magnetosphere–ionosphere link explorer developed cooperatively between China and Europe.It pioneers the use of X-ray imaging technology to perform large-scale imaging of the Earth’s magnetosheath and polar cusp regions.It uses a high-precision ultraviolet imager to image the overall configuration of the aurora and monitor changes in the source of solar wind in real time,using in situ detection instruments to improve human understanding of the relationship between solar activity and changes in the Earth’s magnetic field.The SMILE satellite is scheduled to launch in 2025.The European Incoherent Scatter Sciences Association(EISCAT)-3D radar is a new generation of European incoherent scatter radar constructed by EISCAT and is the most advanced ground-based ionospheric experimental device in the high-latitude polar region.It has multibeam and multidirectional quasi-real-time three-dimensional(3D)imaging capabilities,continuous monitoring and operation capabilities,and multiple-baseline interferometry capabilities.Joint detection by the SMILE satellite and the EISCAT-3D radar is of great significance for revealing the coupling process of the solar wind–magnetosphere–ionosphere.Therefore,we performed an analysis of the joint detection capability of the SMILE satellite and EISCAT-3D,analyzed the period during which the two can perform joint detection,and defined the key scientific problems that can be solved by joint detection.In addition,we developed Web-based software to search for and visualize the joint detection period of the SMILE satellite and EISCAT-3D radar,which lays the foundation for subsequent joint detection experiments and scientific research.

关键词： solar wind Magnetosphere Ionosphere Link Explorer(SMILE)satellite European Incoherent Scatter Sciences Association(EISCAT)-3D radar joint detection

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Lossless Compression Method for the Magnetic and Helioseismic Imager(MHI)Payload

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Research in Astronomy and Astrophysics 2024年第4期24卷 214-221页

作者： Li-Yue Tong Jia-Ben Lin Yuan-Yong Deng Kai-Fan Ji Jun-Feng Hou Quan Wang Xiao Yang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China key laboratory of solar activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

The solar Polar-orbit Observatory(SPO),proposed by Chinese scientists,is designed to observe the solar polar regions in an unprecedented way with a spacecraft traveling in a large solar inclination angle and a small ellipticity.However,one of the most significant challenges lies in ultra-long-distance data transmission,particularly for the Magnetic and Helioseismic Imager(MHI),which is the most important payload and generates the largest volume of data in SPO.In this paper,we propose a tailored lossless data compression method based on the measurement mode and characteristics of MHI data.The background out of the solar disk is removed to decrease the pixel number of an image under compression.Multiple predictive coding methods are combined to eliminate the redundancy utilizing the correlation(space,spectrum,and polarization)in data set,improving the compression ratio.Experimental results demonstrate that our method achieves an average compression ratio of 3.67.The compression time is also less than the general observation period.The method exhibits strong feasibility and can be easily adapted to MHI.

关键词： methods:data analysis techniques:image processing Sun:magnetic fields Sun:photosphere

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A DFT study on Pt single atom loaded COF for efficient photocatalytic CO_(2)reduction

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Journal of Materials Science & Technology 2024年第3期170卷 87-94页

作者： Fei Xie Chuanbiao Bie Jian Sun Zhenyi Zhang Bicheng Zhu laboratory of solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430078China key laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian116600China

Photocatalytic CO_(2)reduction provides a promising strategy for the alleviation of greenhouse effect and energy shortage problem.Metal single atom modification is an effective method to improve the CO_(2)reduction performance of covalent organic framework(COF)photocatalysts,while the intrinsic mechanism is not revealed in depth.Herein,a Pt-COF photocatalytic system was constructed by embedding Pt single atom in TFPT-TMT-COF(TFPT:1,3,5-tris(4-formylphenyl)-triazine,TMT:2,4,6-trimethyl-1,3,5-triazine).Based on density functional theory(DFT)calculation,the geometric structure and electronic property of Pt-COF were investigated,and the CO_(2)adsorption and reduction reaction process on Pt-COF were simulated.The results show that the Pt atom can be steadily anchored in COF via the formation of Pt-N and Pt-C bonds.Moreover,there is strong electronic interaction between Pt and COF.The incorporation of Pt atom benefits the CO_(2)reduction activity of COF from multiple aspects:(ⅰ)reducing the band gap and improving light absorption;(ⅱ)enhancing CO_(2)adsorption and activating the CO_(2)molecule;(ⅲ)decreasing the energy barrier in the hydrogenation step of CO_(2)→COOH,thus facilitating CO_(2)conversion to CO;(ⅳ)inhibiting the hydrogenation of CO,thereby increasing the selectivity of CO.This work brings a novel insight into the excellent CO_(2)reduction performance of Pt modified COF,and provides useful references for the design of single atom photocatalysts.

关键词： Photocatalysis Carbon dioxide reduction Covalent organic framework Pt single atom Theoretical calculation

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Tailored multifunctional hydrazine derivatives for efficient printable hole-conductive-free mesoscopic perovskite solar cells via enhancing defect passivation

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Journal of Energy Chemistry 2024年第8期95卷 357-363页

作者： Minghao Xia Ziwei Zheng Yanjie Cheng Chaoyang Wang Zhaozhen Cui Guodong Zhang Jinwei Gonga Anyi Mei Hongwei Han Michael Gr?tzel Center for Mesoscopic solar Cells Wuhan National Laboratory for Optoelectronics Key Laboratory of Materials Chemistry for Energy Conversion and Storage of Ministry of Education Huazhong University of Science and Technology key laboratory of Flexible Electronics(KLoFE) & Institute of Advanced Materials(IAM) School of Flexible Electronics(Future Technologies) Nanjing Tech University (NanjingTech)

The low-cost and easy large-scale fabrication advantages of printable mesoscopic perovskite solar cells(p-MPSCs) are overshadowed by their limited photovoltaic conversion efficiency(PCE). Here, we introduce the hydrazide derivative of 4-Hydroxybenzoylhydrazine(4-HBH) to improve the PCE of p-MPSCs by inducing enhanced defect passivation. Both carbonyl and hydrazine groups in hydrazide groups present strong interaction with perovskite. The hydroxyl group, as an electron donor group, increases the electron cloud density of the hydrazide group in 4-HBH under the conjugation of the benzene ring,and thus enhances its interaction with perovskite. Additionally, the hydroxy group itself interacts with perovskite and passivates defects synergistically. The hydrazine agents can also reduce I2and suppress the loss of iodine in perovskite films, which inhibits the formation of iodine-related defects.Consequently, p-MPSCs with 4-HBH achieve a high PCE of 19.21%, and present well improved stability.

关键词： Conjugation redox activity Cooperative coordination Multifunctional hydrazine derivatives Printable mesoscopic perovskite solar cells

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Evidence of guide field magnetic reconnection in flapping current sheets

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Earth and Planetary Physics 2024年第4期8卷 650-658页

作者： YunTian Hou SuPing Duan Lei Dai Chi Wang State key laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China key laboratory of solar activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Based on current sheet flapping motion on 27 August 2018 in the dusk flank magnetotail,as recorded by instruments aboard Magnetospheric Multiscale(MMS)spacecraft,we present the first study of guide field reconnection observed in the flux rope embedded in kink-like flapping current sheets near the dusk-side flank of the magnetotail.Unlike more common magnetotail reconnections,which are symmetric,these asymmetric small-scale(λ_(i)~650 km)reconnections were found in the highly twisted current sheet when the direction normal to the sheet changes from the Z direction into the Y direction.The unique feature of this unusual reconnection is that the reconnection jets are along the Z direction-different from outflow in the X direction,which is the more usual situation.This vertical reconnection jet is parallel or antiparallel to the up-and-down motion of the tail’s current sheet.The normalized reconnection rate R is estimated to be~0.1.Our results indicate that such asymmetric reconnections can significantly enlarge current sheet flapping,with large oscillation amplitudes.This letter presents direct evidence of guide field reconnection in a highly twisted current sheet,characterized by enlarged current sheet flapping as a consequence of the reconnection outflow.

关键词： magnetic reconnection magnetotail current sheet

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Enhanced photocatalytic hydrogen production from Co-MOF/CN by nitrogen and sulfur co-doped coal-based carbon quantum dots

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Journal of Rare Earths 2024年第5期42卷 838-850,I0002页

作者： Shiyong Xu Mei Li Yijun Wang Caiyun Gao Rongsheng Xu Zhiliang jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan750021China Ningxia key laboratory of solar Chemical Conversion Technology.North Minzu University.Yinchuan 750021China State key laboratory of National Ethnic Affairs Commission Chemical Technology.North Minzu University Yinchuan750021China

A novel composite photocatalyst for photocatalytic decomposition of water for hydrogen evolution was successfully synthesized by in-situ growth of nitrogen and sulfur co-doped coal-based carbon quantum dots(NSCQDs)nanoparticles on the surface of sheet cobalt-based metal-organic framework(Co-MOF)and graphitic carbon nitride(g-C_(3)N_(4),CN).The structure and properties of the obtained catalysts were systematically analyzed.NSCQDs effectively broaden the absorption of Co-MOF and CN in the visible region.The new composite photocatalyst has high hydrogen production activity and the hydrogen production rate reaches 6254μmol/(g·h)at pH=9.At the same time,NSCQDs synergy Co-MOF/CN composites have good stability.After four cycles of hydrogen production,the performance remains relatively stable.The tran sient photocurrent response and Nyquist plot experimental results further demonstrate the improvement of carrier separation efficiency in composite catalysts.The semiconductor type(n-type semico nductor)of the single-phase catalyst was determined by the Mott-Schottky test,and the band structure was analyzed.The conductive and valence bands of CN are-0.99 and 1.72 eV,respectively,and the conduction and valence bands of Co-MOF are-1.85 and 1.33 eV,respectively.Th e mechanism of the photocatalytic reaction can be inferred,that is,Z-type heterojunction is formed between CN an d Co-MOF,and NSCQDs was used as cocatalyst.

关键词： Nitrogen and sulfur co-doped Coal-based carbon quantum dots Co-MOF CN Photocatalytic hydrogen evolution Rare earths

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Present-day Upper-crustal Strain Rate Field in Southeastern Tibet and its Geodynamic Implications:Constraints from GPS Measurements with ABIC Method

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 265-275页

作者： YANG Shaohua PAN Jiawei LI Haibing SHI Yaolin key laboratory of Continental Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Jiangsu Donghai Continental Deep Hole Crustal activity National Observation and Research Station DonghaiJiangsu 222300China key laboratory of Computational Geodynamics College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China

The Earth’s surface kinematics and deformation are fundamental to understanding crustal evolution.An effective research approach is to estimate regional motion field and deformation fields based on modern geodetic networks.If the discrete observed velocity field is obtained,the velocity related fields,such as dilatation rate and maximum shear strain rate,can be estimated by applying varied mathematical approaches.This study applied Akaike's Bayesian Information Criterion(ABIC)method to calculate strain rate fields constrained by GPS observations in the southeast Tibetan Plateau.Comparison with results derived from other three methods revealed that our ABIC-derived strain rate fields were more precise.The maximum shear strain rate highlighted the Xianshuihe–Xiaojiang fault system as the main boundary for the outward migration of material in southeastern Tibet,indicating rotation of eastern Tibet material around the eastern Himalaya rather than whole extrusion along a fixed channel.Additionally,distinct dilatation rate patterns in the northeast and southwest regions of the fault system were observed.The northeast region,represented by the Longmenshan area,exhibited negative dilatational anomalies;while the southwest region,represented by the Jinsha River area north of 29°N,displayed positive dilatational anomalies.This indicates compression in the former and extension in the latter.Combined with deep geophysical observations,we believe that the upper and lower crusts of the Jinsha River area north of 29°N are in an entire expanding state,probably caused by the escape-drag effect of material.The presence of a large,low-viscosity region south of 29°N may not enable the entire escape of the crust,but instead result in a differential escape of the lower crust faster than the upper crust.

关键词： strain rate differential escape ABIC GPS southeastern Tibet

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Discovery of proqodine A derivatives with antitumor activity targeting NAD(P)H:quinone oxidoreductase 1 and nicotinamide phosphoribosyltransferase

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Chinese Journal of Natural Medicines 2024年第1期22卷 75-88页

作者： SONG Jiangzhou ZOU Guiqing ZHAO Zhou ZHU Ya XUE Jiayu AO Lanjia SUN Huiyong HAO Haiping ZHANG Bo XU Xiaowei State key laboratory of Natural Medicines Key Lab of Drug Metabolism and PharmacokineticsChina Pharmaceutical UniversityNanjing 210009China State key laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China

NAD(P)H:quinone oxidoreductase 1(NQO1)is a flavin protease highly expressed in various cancer cells.NQO1 catalyzes a futile redox cycle in substrates,leading to substantial reactive oxygen species(ROS)production.This ROS generation results in extensive DNA damage and elevated poly(ADP-ribose)polymerase 1(PARP1)-mediated consumption of nicotinamide adenine dinucleotide(NAD^(+)),ultimately causing cell death.Nicotinamide phosphoribosyltransferase(NAMPT),the rate-limiting enzyme in the NAD^(+)salvage synthesis pathway,emerges as a critical target in cancer therapy.The concurrent inhibition of NQO1 and NAMPT triggers hyperactivation of PARP1 and intensive NAD+depletion.In this study,we designed,synthesized,and assessed a novel series of proqodine A derivatives targeting both NQO1 and NAMPT.Among these,compound T8 demonstrated potent antitumor properties.Specifically,T8 selectively inhibited the proliferation of MCF-7 cells and induced apoptosis through mechanisms dependent on both NQO1 and NAMPT.This discovery offers a promising new molecular entity for advancing anticancer research.

关键词： NQO1 ROS NAMPT NAD^(+) T8

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Long-lived lunar volcanism sustained by precession-driven core-mantle friction

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National Science Review 2024年第2期11卷 114-123页

作者： Shuoran Yu Xiao Xiao Shengxia Gong Nicola Tosi Jun Huang Doris Breuer Long Xiao Dongdong Ni State key laboratory of Lunar and Planetary Sciences Macau University of Science and Technology Planetary Science Institute State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences CAS key laboratory of Planetary Sciences Shanghai Astronomical Observatory Institute of Planetary Research German Aerospace Centre(DLR)

Core-mantle friction induced by the precession of the Moon's spin axis is a strong heat source in the deep lunar mantle during the early phase of a satellite's evolution, but its influence on the long-term thermal evolution still remains poorly explored. Using a one-dimensional thermal evolution model, we show that core-mantle friction can sustain global-scale partial melting in the upper lunar mantle until ～3.1 Ga, thus accounting for the intense volcanic activity on the Moon before ～3.0 Ga. Besides, core-mantle friction tends to suppress the secular cooling of the lunar core and is unlikely to be an energy source for the long-lived lunar core dynamo. Our model also favours the transition of the Cassini state before the end of the lunar magma ocean phase(～4.2 Ga), which implies a decreasing lunar obliquity over time after the solidification of the lunar magma ocean. Such a trend of lunar obliquity evolution may allow volcanically released water to be buried in the lunar regolith of the polar regions. As a consequence, local water ice could be more abundant than previously thought when considering only its accumulation caused by solar wind and comet spreading.

关键词： Moon precession orbit volcanism

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