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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1799-1807页

作者： Han Cao Puqi Ning Yunhao Huang Xuhui Wen Wuhan Second Ship Design and Research Institute Wuhan 430205China key Laboratory of Power Electronics and Electric Drive Institute of Electrical EngineeringChinese Academy of SciencesBeijing 100190China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of chinese academy of sciences Beijing 100049China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

Compared to Si devices,the junction temperature of SiC devices is more critical due to the reliability concern introduced by immature packaging technology applied to new *** paper proposes a practical SiC MOSFET junction temperature monitoring method based on the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$*** Section II of the paper,the temperature sensitivity of the on-state voltage$\\boldsymbol{V}_{\\mathbf{ds}(\\mathbf{on})}$is *** hardware of the measurement system is set up in Section III,which consists of an On-state Voltage Measurement Circuit(OVMC),the sampling and isolation ***,a calibration method based on the self-heating of the SiC MOSFET chip is presented in Section *** the final Section,the junction temperature is monitored synchronously according to the calibration *** proposed method is applied to a Buck converter and verified by both an Infrared Radiation(IR)camera and a Finite Element Analysis(FEA)tool.

关键词： Junction temperature Silicon Carbide(SiC)MOSFET TSEP

Black holes as the source of dark energy:A stringent test with high-redshift JWST AGNs

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 181-188页

作者： Lei Lei Lei Zu Guan-Wen Yuan Zhao-Qiang Shen Yi-Ying Wang Yuan-Zhu Wang Zhen-Bo Su Wen-Ke Ren Shao-Peng Tang Hao Zhou Chi Zhang Zhi-Ping Jin Lei Feng Yi-Zhong Fan Da-Ming Wei key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black holes(BHs)with an index of k≈3;hence,BHs serve as the astrophysical source of dark ***,the data sample is limited for the redshifts of≤*** recent years,the James Webb Space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z~***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black holes with k=3 at a confidence level of~2σ,which challenges the hypothesis that BHs serve as the origin of dark *** work on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark energy supermassive black hole active galactic nuclei James Webb Space Telescope

Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause

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Earth and Planetary Physics 2024年第1期8卷 133-154页

作者： RongCong Wang JiaQi Wang DaLin Li TianRan Sun XiaoDong Peng YiHong Guo National Space Science Center Chinese Academy of SciencesBeijing 100190China University of chinese academy of sciences Beijing100049China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China

Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space *** Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray ***,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the *** analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration *** makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical *** propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the *** idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch *** Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the *** results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural *** restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving

关键词： Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray imager magnetopause image restoration

Aging Mongolian pine plantations face high risks of drought-induced growth decline:evidence from both individual tree and forest stand measurements

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Journal of Forestry Research 2024年第2期35卷 109-120页

作者： Mingyong Li Leilei Yang Yu Cao Dedong Wu Guangyou Hao CAS key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China key Laboratory of Terrestrial Ecosystem Carbon Neutrality Liaoning ProvinceShenyang 110016People’s Republic of China Daqinggou Ecological Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China University of chinese academy of sciences Beijing 100049People’s Republic of China Research Institute of Sand Control and Utilization Liaoning ProvinceFuxin 123000People’s Republic of China

Discerning vulnerability differences among different aged trees to drought-driven growth decline or to mortality is critical to implement age-specific countermeasures for forest management in water-limited *** important species for afforestation in dry environments of northern China,Mongolian pine(Pinus sylvestris *** Litv.)has recently exhibited growth decline and dieback on many sites,particularly pronounced in old-growth ***,changes in response to drought stress by this species with age as well as the underlying mechanisms are poorly *** this study,tree-ring data and remotely sensed vegetation data were combined to investigate variations in growth at individual tree and stand scales for young(9-13 years)and aging(35-52 years)plantations of Mongolian pine in a water-limited area of northern China.A recent decline in tree-ring width in the older plantation also had lower values in satellited-derived normalized difference vegetation indices and normalized difference water indices relative to the younger *** addition,all measured growth-related metrics were strongly correlated with the self-calibrating Palmer drought severity index during the growing season in the older *** of growth to drought of the older plantation might be attributed to more severe hydraulic limitations,as reflected by their lower sapwood-and leaf-specific hydraulic *** study presents a comprehensive view on changes of growth with age by integrating multiple methods and provides an explanation from the perspective of plant hydraulics for growth decline with *** results indicate that old-growth Mongolian pine plantations in water-limited environments may face increased growth declines under the context of climate warming and drying.

关键词： Tree age Drought stress Mongolian pine plantation Tree rings Remote sensing Plant hydraulics

First Digit Distributions of Gamma-Ray Bursts

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Research in Astronomy and Astrophysics 2024年第5期24卷 70-75页

作者： Hou-Yu Lai Jun-Jie Wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space sciences University of Science and Technology of ChinaHefei 230026China

The occurrence of the first significant digits from real world sources is usually not equally distributed,but is consistent with a logarithmic distribution instead,known as Benford’s *** this work,we perform a comprehensive investigation on the first digit distributions of the duration,fluence,and energy flux of gamma-ray bursts (GRBs) for the first *** a complete GRB sample detected by the Fermi satellite,we find that the first digits of the duration and fluence adhere to Benford’s ***,the energy flux shows a significant departure from this law,which may be due to the fact that a considerable part of the energy flux measurements is restricted by lack of spectral *** on the conventional duration classification scheme,we also check if the durations and fluences of long and short GRBs (with duration T_(90)>2 s and T_(90)≤2 s,respectively) obey Benford’s *** find that the fluences of both long and short GRBs still agree with the Benford distribution,but their durations do not follow Benford’s *** results hint that the long–short GRB classification scheme does not directly represent the intrinsic physical classification scheme.

关键词： (stars:)gamma-ray burst general-methods statistical-astronomical databases miscellaneous

The genome-wide meiotic recombination landscape in ciliates and its implications for crossover regulation and genome evolution

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Journal of Genetics and Genomics 2024年第3期51卷 302-312页

作者： Lu Fu Chen Gu Kazufumi Mochizuki Jie Xiong Wei Miao Guangying Wang key Laboratory of Aquatic Biodiversity and Conservation Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China University of chinese academy of sciences Beijing 100049China Institute of Human Genetics(IGH) CNRSUniversity of Montpellier34396 MontpellierFrance key Laboratory of Breeding Biotechnology and Sustainable Aquaculture Chinese Academy of SciencesWuhanHubei 430072China key Laboratory of Lake and Watershed Science for Water Security Chinese Academy of SciencesNanjingJiangsu 210008China

Meiotic recombination is essential for sexual reproduction and its regulation has been extensively studied in many ***,genome-wide recombination landscape has not been reported in ciliates and it remains unknown how it is affected by the unique features of ciliates:the synaptonemal complex(SC)-independent meiosis and the nuclear ***,we show the recombination landscape in the model ciliate Tetrahymena thermophila by analyzing single-nucleotide polymorphism datasets from 38 hybrid *** detect 1021 crossover(CO)events(35.8 per meiosis),corresponding to an overall CO rate of 9.9 cM/***,gene conversion by non-crossover is rare(1.03 per meiosis)and not biased towards G or C *** with the reported roles of SC in CO interference,we find no obvious sign of CO *** tends to occur within germ-soma common genomic regions and many of the 44 identified CO hotspots localize at the centromeric or subtelomeric *** ontology analyses show that CO hotspots are strongly associated with genes responding to environmental *** discuss these results with respect to how nuclear dimorphism has potentially driven the formation of the observed recombination landscape to facilitate environmental adaptation and the sharing of machinery among meiotic and somatic recombination.

关键词： Meiotic recombination Hotspot Crossover interference Adaptive evolution

El Niño and the AMO Sparked the Astonishingly Large Margin of Warming in the Global Mean Surface Temperature in 2023

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Advances in Atmospheric sciences 2024年第6期41卷 1017-1022页

作者： Kexin LI Fei ZHENG Jiang ZHU Qing-Cun ZENG International Center for Climate and Environment sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China University of chinese academy of sciences Beijing 100049China

In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since *** 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming has become one of the hottest topics in the scientific community and is closely connected to the future development of human *** analyzed the monthly varying global mean surface temperature(GMST)in 2023 and found that the globe,the land,and the oceans in 2023 all exhibit extraordinary warming,which is distinct from any previous year in recorded *** on the GMST statistical ensemble prediction model developed at the Institute of Atmospheric Physics,the GMST in 2023 is predicted to be 1.41℃±0.07℃,which will certainly surpass that in 2016 as the warmest year since 1850,and is approaching the 1.5℃ global warming *** to 2022,the GMST in 2023 will increase by 0.24℃,with 88%of the increment contributed by the annual variability as mostly affected by El Niñ***,the multidecadal variability related to the Atlantic Multidecadal Oscillation(AMO)in 2023 also provided an important warming background for sparking the GMST *** a result,the GMST in 2023 is projected to be 1.15℃±0.07℃,with only a 0.02℃ increment,if the effects of natural variability—including El Niño and the AMO—are eliminated and only the global warming trend is considered.

关键词： record-breaking temperature global mean surface temperature El Niño AMO global warming

Prospects to study hyperon-nucleon interactions at BESIII

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chinese Physics C 2024年第7期48卷 22-30页

作者：代建平李海波妙晗张剑宇 Department of Physics Yunnan UniversityKunming 650091China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Beijing 100049China

The prospects to study hyperon-nucleus/nucleon interactions at BESIII and similar e^(+)e^(-)colliders are analyzed in this *** the large quantity of hyperons produced by the decay of 10 billion J/■and 2.7 billion(3686)collected at BESIII,the cross sections of several specific elastic and inelastic hyperon-nucleus reactions can be measured via scattering between hyperons and nucleus in the dense objects of the BESIII ***,the cross sections of the corresponding hyperon-nucleon interactions can be extracted from further phenomenological *** interactions between antihyperons and nucleus/nucleon,including scattering and annihilation,can also be studied using the method proposed in this *** results will definitely benefit the realization of precise probes for hyperon-nuclei/nucleus interactions and establish constraints to study the potential of strong interaction,the origin of color confinement,a unified model for baryon-baryon interactions,and the internal structure of neutron *** addition,the desirable prospects of corresponding studies in the future Super Tau-Charm Factory(STCF)are discussed and estimated in this study.

关键词： hyperon-nucleon interaction BESIII STCF neutron star

Designing ABC-6 family small pore zeolites by epitaxial growth approach

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chinese Chemical Letters 2024年第3期35卷 508-512页

作者： Xiaohui Cui Jia Lv Chao Ma Yujiao Wang Zhenghao Jia Daliang Zhang Peng Guo Zhongmin Liu Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450001China National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Multi-scale Porous Materials Center Institute of Advanced Interdisciplinary Studies&School of Chemistry EngineeringChongqing UniversityChongqing 400044China University of chinese academy of sciences Beijing 100049China Division of Energy Research Resources Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Aluminosilicate small pore zeolites belonging to ABC-6 family play crucially important roles in the high methanol conversion with the high selectivity of light olefins,gas separation and storage,and selective catalytic reduction of NO_(x).In this work,we report a general method,called the epitaxial growth approach,for designing ABC-6 family small pore *** is mainly realized through the epitaxial growth on the nonporous SOD-type zeolite in the presence of inorganic cations(Na^(+)and K^(+))combined with a variety of organic structure directing agents(OSDAs).In this case,a series of ABC-6 family small pore zeolites such as ERI-,SWY-,LEV-,AFX-,and PTT-type zeolites have been successfully synthesized within a few *** importantly,the advanced focused ion beam(FIB)and the low-dose high-resolution transmission electron microscopy(HRTEM)imaging technique have been utilized for unraveling the zeolite heterojunction at the atomic level during the epitaxial growth *** turns out(222)crystallographic planes of the SOD-type zeolite substrate provide unique pre-building units,which facilitate the growth of targeted ABC-6 family small pore zeolites along its ***,the morphologies of ERI-type zeolite can also be tuned through the epitaxial growth approach,achieving a longer lifetime in the methanol conversion.

关键词： Zeolite structure Zeolite synthesis Structural characterizations Low-dose imaging Focused ion beam

Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1241-1248页

作者： Chen Li Wenhui Ma Yang Li Kuixian Wei Center for Lunar and Planetary sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical *** involves systematic and theoretical engineering technology for utilizing planetary resources in ***,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the *** this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil *** microstructural characteristics of the lunar soil may drastically change its metallurgical *** main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral *** nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar *** ions injected by solar wind may promote the hydrogen reduction *** widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar ***,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar *** is a property that earth samples and tradi-tional simulated lunar soil *** application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance