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醋酸对氧化铟纳米晶形貌的影响及相关等离激元性质研究（英文）

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Science China Materials 2025年

作者：苏江彤李培显刘喆刘子沣侯小琪段俊丽戴宁李洋 School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences university of chinese academy of sciences Shanghai Institute of Technical Physics Chinese Academy of Sciences School of Chemistry and Material Science Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences

金属氧化物纳米晶体具有独特的尺寸及形貌依赖的光学/光电特性,因此实现金属氧化物纳米晶的可控合成对其光电应用具有重要意义.然而,目前对于金属氧化物纳米晶尺寸和形貌的关键影响因素研究相对较少.在本工作中,我们发现,在前驱体反应...

金属氧化物纳米晶体具有独特的尺寸及形貌依赖的光学/光电特性,因此实现金属氧化物纳米晶的可控合成对其光电应用具有重要意义.然而,目前对于金属氧化物纳米晶尺寸和形貌的关键影响因素研究相对较少.在本工作中,我们发现,在前驱体反应过程形成的副产物—醋酸,通过影响纳米晶的成核过程,对氧化铟纳米晶的形貌控制起了决定性作用.具体地,醋酸过量时会诱导纳米晶各向异性生长,生成纳米花;而在少量或者无醋酸条件下,所得氧化铟纳米晶呈球形.进一步地,我们探究了氧化铟纳米晶的几何形状对表面等离基元性质的影响.通过调节几何形状,可以得到在近红外到中波红外具有可调谐的表面等离基元共振吸收的等离子体纳米晶,同时展现出优异的稳定性.本工作深入探究了金属氧化物纳米晶的几何形状影响机制,为基于等离子体金属氧化物纳米晶的光电和光热应用提供更多指导.

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Pyrite Geochemistry and S-Hg Isotopes Reveal the Ore Genesis of the Hydrothermal Vein-type Cuiluan Ag-Pb-Zn Deposit in NE China

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Journal of Earth Science 2025年

作者： Lidong Zhang Changzhou Deng Yao Tang Xinran Ni Bizheng Yang Shanshan Liang Weipeng Liu Jishuang Ding Xiaohui Zeng Heilongjiang Institute of Natural Resources Survey State Key Laboratory of Ore Deposit Geochemistry， Institute of Geochemistry， chinese academy of sciences College of Earth and Planetary sciences， Chengdu university of Technology

The Xing'an-Mongolian orogenic belt is an important Ag-Pb-Zn metallogenic province in China. The study on the genesis of the newly discovered Cuiluan hydrothermal vein-type Ag-Pb-Zn deposit located in the Lesser Xing'an Range， within the eastern of Xing'an-Mongolian orogenic belt， is pivotal in understanding the metallogenic mechanism and regularity of Ag-Pb-Zn deposits in this region. This study utilizes pyrite trace elements and sulfur isotopic geochemistry， and mercury isotope of rocks and ores to constrain the genesis of the Cuiluan deposit. Pyrite geochemical data show that Ag exists in the form of galena inclusions (Ag++(Bi3+， Sb3+) ? Pb2+) in the polymetallic sulfide stage， and independent Ag-bearing minerals （matildite and gustavite） precipitate during the main mineralization stage. The small varied δ34S values （3.24‰ - 4.94‰） of pyrites from four hydrothermal stages are within the range of magmatic S isotopes， indicating that the ore-forming fluid of the Cuiluan deposit mainly originated from the magma. The Δ199Hg values of the ores are close to 0‰， which are consistent with the Δ199Hg values of mantle， further indicating that the ore-forming materials came from the lithospheric mantle. Combined with the regional tectonic evolution， we conclude that the plate subduction of Paleo-oceans in NE China triggered the partial melting of metasomatized mantle. The mantle-derived magma rose along the deep fractures and evolved ore-forming fluids， and finally caused the formation of Cuiluan quartz vein-type Ag-Pb-Zn deposit in the shallow crust. Accompany with previous documents， we infer that the fractures in the large-scale “Granite Sea” in the Lesser Xing'an Range may have significant potential for vein-type Ag-Pb-Zn exploration.

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Calibration of the Solar X-ray Detector on-board the Macao Science Satellite-1B for Soft X-ray Detection

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Science China Earth sciences 2025年第1期68卷 11-26页

作者： Man-Hei NG Xiaoping ZHANG Jianwu CHEN Yongqiang SHI Fuchang ZUO Wenxi PENG Weichun FU Liansheng LI Pengwei LUO Chi-Long TANG Guozheng ZHANG Zhiwu MEI Li WANG Cunhui LI Jiaming OU Yanyan XU State Key Laboratory of Lunar and Planetary sciences Macau University of Science and Technology China National Space Administration (CNSA) Macau Center for Space Exploration and Science Space Optoelectronic Measurement and Perception Laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of Physics

The Solar X-ray Detector(SXD) on-board the Macao Science Satellite-1B(MSS-1B) was successfully launched via the chinese Long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The MSS-1B/Soft X-ray Detection Units(SXDUs) employ two silicon drift detectors(SDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the SXDUs deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the MSS-1B/SXDUs, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the MSS-1B/SXDUs to the data collected by the Geostationary Operational Environmental Satellite(GOES), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SXDUs, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative MSS-1B/Solar X-ray Detector facilitates concurrent observations of solar soft and hard X-rays, thereby making valuable contributions to the advancements in solar research.

关键词： Macao Science Satellite-1B (MSS-1B) Calibration Solar X-Ray Detector Spectrometer Soft X-rays Solar flares Solar abundances

A robust statistical prediction model for late-summer heavy precipitation days in North China

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Science China Earth sciences 2025年第1期68卷 158-171页

作者： Shunli JIANG Tingting HAN Xin ZHOU Huijun WANG Zhicong YIN Xiaolei SONG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University for Information Science and Technology Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)

Recently, heavy precipitation(HP) events have occurred frequently in North China(NC), causing devastating economic losses and human fatalities. However, the short-term climate prediction of HP is quite limited. Combining year-to-year increment(DY) method and sliding correlations, we developed a robust seasonal prediction model for late-summer HP days(HPDs) in NC during 1982–2022, utilizing three independent predictors—February sea surface temperature(SST) in the Indian Ocean(SST＿IO), February snow depth over North Asia(SDE＿NA), and May melted snow depth in NC(MSDE＿NC). The SST＿IO anomalies affect NC's precipitation through the Pacific-Japan pattern. The SDE＿NA anomalies are associated with East Asian anomalous anticyclone by southeastern propagation of Rossby wave at Eurasia. The MSDE＿NC anomalies are followed by vertical motion and moisture anomalies in situ and thereby cause precipitation anomalies. This prediction model can well simulate the variations of the HPDs, with a correlation coefficient(CC) of 0.81(0.65) between the observed and predicted HPDs＿DY(HPDs＿anomaly). The percentage with the same sign for 15 extreme HPDs＿anomaly years(PSSE) is 100%.Moreover, in the cross-validation test during 1982–2022, the PSSE for HPDs＿anomaly is as high as 100%, along with a low rootmean-square error of 1.14. For independent hindcasts during 2013–2022, the CC between the observed and predicted HPDs＿DY(HPDs＿anomaly) is 0.93(0.83), together with high Nash-Sutcliffe efficiency(0.82) and agreement index(0.89). Specifically, the predictions are broadly consistent with the observations for 2015, 2016, 2017, 2021, and 2022, reflecting excellent performance of this prediction model of HPDs in NC.

关键词： Heavy precipitation at North China Year-to-year increment approach Robust seasonal prediction Sea surface temperature Snow depth

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一维范德华原子链材料的研究进展（英文）

Science China Materials 2025年

作者：占鹏鑫贺平王子珂罗灵心崔雪萍郑健 Beijing National Laboratory for Molecular sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences university of chinese academy of sciences

由于量子限域效应的影响,石墨烯等二维(2D)材料表现出独特而卓越的性能,突显了低维材料在基础研究和实际应用中的重要性.这导致人们对具有更低维度的一维(1D)范德华原子链材料抱有很高的期望.与二维材料相比,一维范德华原子链在两个维...

由于量子限域效应的影响,石墨烯等二维(2D)材料表现出独特而卓越的性能,突显了低维材料在基础研究和实际应用中的重要性.这导致人们对具有更低维度的一维(1D)范德华原子链材料抱有很高的期望.与二维材料相比,一维范德华原子链在两个维度上都达到了物理极限,从而产生了更明显的量子限域效应,引发了意想不到的物理现象,并将建立一个全新的探索领域.本文综述了一维范德华原子链材料的研究进展.首先,我们总结了一维范德华原子链材料的各种类型和结构.随后,我们讨论了他们的制备和表征方法.最后,我们展望了一维范德华原子链材料在未来发展中将面临的挑战以及机遇.

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Investigations of liquid-liquid transitions in metallic melts by fast differential scanning calorimetry

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Qi Cheng Yonghao Sun Weihua Wang Beijing National Laboratory for Molecular sciences College of Chemistry and Molecular Engineering Peking University School of Physics and Electronic Information Anhui Normal University Institute of Physics Chinese Academy of Sciences Songshan Lake Materials Lab

Liquid-liquid transition in metallic melts is an intriguing phenomenon often confused with liquid-liquid separation, oxidation or precipitation. Here, we employ a state-of-the-art ultrafast chip-based differential scanning calorimeter to investigate the thermal behavior of six metallic melts, ranging from unary to quinary systems, at temperatures above their liquidus. Calorimetric signals of liquid-liquid transition vary across systems: Sn melts showed no direct endothermic or exothermic events, though liquid-liquid transition influenced solidification and melting temperatures, while Yb-Zn melts exhibited an exothermic peak during cooling,indicating liquid-liquid transition. Thermal signals in other systems including Li, Pd-Ni-P, Yb-Mg-Zn-Cu and Au-Ag-Pd-Cu-Si,are primarily driven by compositional changes. Our in-situ analysis provides new insights into the structural and compositional evolution of metallic melts, offering significant implications for the design and processing of novel materials.

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The low-latitude sodium layer:comparative data from lidar observations at Hainan,China and São Paulo,Brazil

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Earth and Planetary Physics 2025年第1期9卷 39-53页

作者： Fang Wu Jing Jiao GuoTao Yang LiFang Du ZhengKuan Liu HaoRan Zheng JiXin Guo ShaoHua Gong YaJun Zhu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Hainan National Field Science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China university of chinese academy of sciences Beijing 100049China China-Brazil Joint Laboratory for Space Weather NSSC/INPESão Josédos Campos 12227-010Brazil School of Physics and Electronics Engineering Hainan Normal UniversityHaikou 571158China

Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude *** sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s *** paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the *** low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in ***,maximal Na density over Brazil is greater than that over *** variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before *** variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain *** suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.

关键词： metallic sodium layer seasonal variation nocturnal variation lidar

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The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing Xue Yuejia Ma Ke Ye Xue Zhao Fangliang Ge Feifei Zheng Lulu Liu Xu Gao Dayong Wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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