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High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SATech-01 satellite

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Science China Technological sciences 2025年

作者： Hongbo XUE Wei SONG Haoran ZHAO Yiteng ZHANG Shanzhi YE Jindong WANG Ran TAO Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang XUE Yingying TANG Liu LIU Jinsong LI Xiaocheng ZHU Baoquan LI Jinguo LIU Wen CHEN Xiaofeng ZHANG Yonghe ZHANG Lei LI State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences innovation academy for Microsatellites Chinese Academy of Sciences

On July 27, 2022, a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer（referred to as the CPT system） was launched onboard the Space Advanced Technology demonstration satellite（SATech-01） by a ZK-1A rocket. The payload comprises a scalar coherent population trapping magnetometer（CPTM）, triaxial anisotropic magnetoresistance magnetometer（AMRM）, and nano star tracker mounted on a non-magnetic telescopic tubular mast. This configuration enables synchronized measurement of scalar and vector geomagnetic fields, as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite platforms. On November 7, 2022,the novel telescopic tubular mast was deployed in orbit, extending to a length of 5.28 m. The CPTM, an absolute scalar magnetometer with an omnidirectional sensor, is the first China-developed quantum/atomic magnetometer successfully operating in space. In orbit, the CPTM has sensitivity of ～10 pT/Hz1/2and can automatically operate under complex magnetic field variations. The difference between the scalar fields obtained using the CPTM and CHAOS model has a mean deviation of–3.73 n T and a standard deviation of 26.11 nT（1σ）, without on-orbit calibration or correction. The miniaturized AMRM has a sensitivity of ～0.3 n T/Hz1/2and maintains stable and reliable operation in orbit. The low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″（1σ） in orbit. The mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system's performance,automation level, and reliability.

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Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-Sheng Nong Hao-Fan Qian Ying-Chun Chen Pu-Sheng Wang Liu-Zhu Gong Hefei National Research Center for Physical sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories chinese academy of sciences School of Astronomy and Space sciences University of chinese academy of sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics chinese academy of sciences Institute of Space sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics innovation academy for Microsatellites chinese academy of sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics chinese academy of sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space sciences University of Science and Technology of China Institute of Deep Space sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Dramatical enhancement of circular dichroism in chiral hybrid perovskites via carboxylic hydrogen bond engineering

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Science China Chemistry 2025年

作者： Hang Li Xinling Li Peng Wang Tingting Zhu Ruiqing Li Huang Ye Yaru Geng Hongliang Dai Junhua Luo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of chinese academy of sciences Fujian College University of Chinese Academy of Sciences College of Chemistry Fuzhou University College of Chemistry and Materials Key Laboratory of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal University

Chiral hybrid perovskites （CHPs） have been regarded as promising candidates for developing chiroptoelectronics ***,circular dichroism （CD）,as one of the most important characteristics to evaluate the chiroptical activity,remains at a comparatively low level in CHPs compared to other chiral materials,which hinders the successful applications of CHPs in stateof-the-art ***,exploring new methods for enhancing CD in CHPs is urgently needed and remains ***,enhanced CD response has been successfully realized via constructing carboxylic hydrogen bonding in chiralachiral mixed cations perovskites （R/S-PPA）2（ABA）PbBr5（2R/2S）(PPA=1-phenylpropylamine,ABA=4-aminobutyric acid).Compared with the prototype （R/S-PPA）PbBr3（1R/1S）,2R/2S provide intimate connections between organic units and inorganic parts via carboxylic hydrogen bonding N–H···O bridge,contributing new chirality transfer paths.A larger inorganic skeletons’helicity in 2R/2S predicts a high degree of chirality ***,2R/2S exhibit significantly enhanced CD response with an anisotropy factor amplified by an order of ***,bright blue circularly polarized luminescence applications are achieved in 2R/*** work systematically investigates the correlation between CD and hydrogen bonding interaction in CHPs,meanwhile providing a new avenue to develop the application potential of chiral materials in chiroptoelectronics.

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Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing Wang Wei Wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of chinese academy of sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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一种基于偶氮键一级断裂与C–C键二级断裂释放药物的β-lapachone高分子纳米前药用于肿瘤选择性治疗（英文）

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Science China Materials 2025年

作者：赵唯栋郑梦飞褚虹宇张景宣王昆杨晨光沈娜汤朝晖 Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences School of Applied Chemistry and Engineering University of Science and Technology of China Department of Gastrointestinal Colorectal and Anal Surgery China-Japan Union Hospital of Jilin University Department of Pathogenbiology State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases College of Basic Medicine Jilin University

lapachone (β-Lap)是一种极具潜力的邻萘醌类抗肿瘤药物,但β-Lap临床应用受限于低水溶性和严重的毒副作用.前药修饰策略可有效增强药物的肿瘤选择性,但β-Lap受限于缺乏可修饰基团.本文设计了一种新型偶氮键一级断裂和碳碳键(C–C)二...

lapachone (β-Lap)是一种极具潜力的邻萘醌类抗肿瘤药物,但β-Lap临床应用受限于低水溶性和严重的毒副作用.前药修饰策略可有效增强药物的肿瘤选择性,但β-Lap受限于缺乏可修饰基团.本文设计了一种新型偶氮键一级断裂和碳碳键(C–C)二级断裂的β-Lap高分子纳米前药(Azo-Lap NP),自消除的对氨基苯基连接子通过偶氮键连接聚谷氨酸,在高表达NQO1和低pH的肿瘤环境下,实现肿瘤响应性β-Lap释放. Azo-Lap NPs对β-Lap的有效共价负载可显著提高β-Lap的给药剂量,并延长药物的肿瘤停留时间.此外, Azo-Lap NPs通过避免溶血和高铁血红蛋白的产生显著降低β-Lap的毒副作用.通过小鼠抑瘤实验验证了Azo-Lap NPs安全性.在4T1模型中, Azo-Lap NPs组的抑瘤率明显高于β-Lap组.本研究为肿瘤选择性递送β-Lap提供了一种更有效且安全的高分子纳米前药.

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Gene editing in plants:progress and challenges

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National Science Review 2019年第3期6卷 421-437页

作者： Yanfei Mao Jose Ramon Botella Yaoguang Liu Jian-Kang Zhu Shanghai Center for Plant Stress Biology CAS Center of Excellence in Molecular Plant Sciences Chinese Academy of Sciences School of Agriculture and Food sciences University of Queensland State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of Life Sciences South China Agricultural University Department of Horticulture and Landscape Architecture Purdue University

The clustered regularly interspaced short palindromic repeat(CRISPR)-associated protein 9(Cas9)genome editing system is a powerful tool for targeted gene modifications in a wide range of species,including plants. Over the last few years, this system has revolutionized the way scientists perform genetic studies and crop breeding, due to its simplicity, flexibility, consistency and high efficiency. Considerable progress has been made in optimizing CRISPR/Cas9 systems in plants, particularly for targeted gene mutagenesis. However, there are still a number of important challenges ahead, including methods for the efficient delivery of CRISPR and other editing tools to most plants, and more effective strategies for sequence knock-ins and replacements. We provide our viewpoint on the goals, potential concerns and future challenges for the development and application of plant genome editing tools.

关键词： CRISPR Cas9 genome editing base editing gene targeting crop breeding

Optical storage of circular airy beam in atomic vapor

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chinese Physics B 2024年第8期33卷 263-269页

作者：常虹杨欣马燕杨鑫琪曹明涛张晓斐董瑞芳张首刚 Key Laboratory of Time Reference and Applications National Time Service CenterChinese Academy of SciencesXi'an 710600China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic DevicesSchool of PhysicsXi'an Jiaotong UniversityXi'an 710049China Department of Physics Shaanxi University of Science and TechnologyXi'an 710021China Hefei National Laboratory Hefei 230088China

The realization of quantum storage of spatial light field is of great significance to the construction of high-dimensional quantum *** this paper,we experimentally realize the storage and retrieval of circular Airy beams(CABs)by using theΛ-type three-level energy system based on the electromagnetically induced transparency in a hot rubidium atomic vapor *** weak probe beam field is modulated with phase distribution of CABs by a spatial light *** store the probe circular Airy beam(CAB)into the rubidium atomic vapor cell and retrieve it after the demanded *** quantitatively analyze the storage results and give corresponding theoretical ***,we investigate the autofocusing and self-healing effect of the retrieved CAB,which indicates that the properties and beam shape of CAB maintain well after *** work will have potential applications in the storage of high-dimensional quantum information,and is also useful for improving the channel capacities of quantum internet.

关键词： circular Airy beam optical storage autofocusing effect self-healing effect

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Transformation of olivine to diopside via interaction with carbonatite melts

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Science China Earth sciences 2023年第10期66卷 2332-2339页

作者： Jing WANG Ben-Xun SU Sanjeewa P.K.MALAVIARACHCHI Patrick Asamoah SAKYI Prasanna L.DHARMAPRIYA Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of chinese academy of sciences Beijing100049China Department of Geology Faculty of ScienceUniversity of PeradeniyaPeradeniya20400Sri Lanka Department of Earth Science School of Physical and Mathematical SciencesUniversity of GhanaLegon-AccraGhana

Numerous empirical and experimental studies have documented the consumption of orthopyroxene and production of clinopyroxene in mantle peridotite during carbonatite metasomatism,whereas little attention has been paid to whether and how olivine is compositionally modified through the same process of carbonatite ***,we present the discovery of well-preserved reaction features in olivine from typical calciocarbonatites from Sri *** olivine grains experienced serpentinization along the cracks and in their rims and are generally surrounded outwardly by serpentine,tremolite and diopside *** inner serpentine zone is dominated by serpentine with tiny magnetite,whereas the mantle tremolite zone is characterized by euhedral tremolite and intergrowth of dolomite with small amounts of serpentine relics and *** outer diopside zone shows spongy texture and commonly encloses olivine,serpentine,tremolite and dolomite,which are also observed in interstitial diopside grains in the *** profile analyses reveal that these olivine grains display decreasing FeO and increasing MgO contents and thus elevating Fo values from their cores to the reaction rims,while the serpentine inherits compositions from the *** mapping images demonstrate outward diffusion of Si and Mg in the serpentine zones and contribution of Ca from carbonatite melts during tremolite *** interaction with carbonatite melts produced Si-and Mg-poor and Ca-rich diopside relative to the reactant *** observations suggest that the interaction with carbonatite melts first transformed olivine to diopside through serpentinization,followed by *** diopside formed through olivine-carbonatite melt interaction is anomalously depleted in Na and Al and enriched in Ca,which are distinct from those generated in interactions between orthopyroxene and both carbonatite and silicate *** implies that for the first time some w

关键词： Olivine Carbonatite Diopside Tremolite Melt-mineral interaction

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