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RKKY interaction in helical higher-order topological insulators

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chinese Physics B 2024年第7期33卷 587-593页

作者：金莎李健李清旭朱家骥 School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China Institute for Advanced Sciences Chongqing University of Posts and TelecommunicationsChongqing 400065China Southwest Center for Theoretical Physics Chongqing UniversityChongqing 401331Chin

We theoretically investigate the Ruderman–Kittel–Kasuya–Yosida(RKKY) interaction in helical higher-order topological insulators(HOTIs), revealing distinct behaviors mediated by hinge and Dirac-type bulk carriers. Our findings show that hinge-mediated interactions consist of Heisenberg, Ising, and Dzyaloshinskii–Moriya(DM) terms, exhibiting a decay with impurity spacing z and oscillations with Fermi energy εF. These interactions demonstrate ferromagnetic behaviors for the Heisenberg and Ising terms and alternating behavior for the DM term. In contrast, bulk-mediated interactions include Heisenberg, twisted Ising, and DM terms, with a conventional cubic oscillating decay. This study highlights the nuanced interplay between hinge and bulk RKKY interactions in HOTIs, offering insights into designs of next-generation quantum devices based on HOTIs.

关键词： magnetic impurity interactions magnetic ordering spintronics topological phases

Mars exploration——In situ K-Ar dating of jarosite

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Science china Earth Sciences 2024年第3期67卷 641-656页

作者： Jing YANG Dewen ZHENG Ying WU Hong CHEN li YANG Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

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Recent advances in Ir/Ru-based perovskite electrocatalysts for oxygen evolution reaction

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Rare Metals 2024年第7期43卷 2891-2912页

作者： Zhi-Qi Jiang Cheng-Zhen Fan Jun-Yu Pan li Shao Hao Chen Erum Pervaiz Yan Dong Tong-Zhou Wang Xue-Rong Zheng Ji-Hong li Yi-Da Deng School of Materials Science and Engineering Hainan UniversityHaikou570228Chin Department of Chemical Engineering School of Chemical and Materials Engineering(SCME)National University of Sciences&Technology(NUST)Islamabad 44000Pakistan Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071Chin

Oxygen evolution reaction(OER)is a kinetically harsh four-electron anode reaction that requires a large overpotential to provide current and is of great importance in renewable electrochemical ***/Rubased perovskite oxides hold great significance for application as OER electrocatalysts,due to that their multimetal-oxide forms can reduce the use of noble metals,and their compositional tunability can modulate the electronic structure and optimize OER ***,high operating potentials and corrosive environments pose a serious challenge to the development of durable Ir-based and Ru-based perovskite *** efforts have been dedicated to improving the Ir/Ru-based perovskite activity to enhance the efficiency;however,progress in improving the durability of Ir/Ru-based perovskite electrocatalysts has been rather *** this review,the recent research progress of Ir/Ru-based perovskites is reviewed from the perspective of heteroatom doping,structural modulation,and formation of *** dissolution mechanism studies of Ir/Ru and experimental attempts to improve the durability of Ir/Ru-based perovskite electrocatalysts are *** and outlooks for further developing Ru-and Irbased perovskite oxygen electrocatalysts are also presented.

关键词： Oxygen evolution reaction Ir/Ru-based perovskites Stability Electrocatalysts

Akt3 promotes cancer stemness in triple-negative breast cancer through YB1-Snail/Slug signaling axis

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Genes & Diseases 2023年第2期10卷 301-306页

作者： Ye Tian Jiang li Tsz Chung cheung Vincent Tam C. Geoffrey Lau Xin Wang Y.Rebecca chin Tung Biomedical Sciences Centre Department of Biomedical SciencesCity University of Hong KongKowloonHong Kong SARChina Department of Neuroscience City University of Hong KongKowloonHong Kong SARChina City University of Hong Kong Shenzhen Research Institute ShenzhenGuangdong 518057China Department of Surgery The Chinese University of Hong KongShatinHong Kong SARChina

Dear Editor,Triple-negative breast cancer(TNBC)is an aggressive breast cancer subtype enriched in cancer stem cells(CSCs),which is characterized by high malignancy and drug resistance.1 The PI3K/Akt signaling cascade is frequently hyperactivated in *** and non-redundant functions of the three Akt isoforms in tumorigenesis,however,have not been studied *** is noteworthy that despite a few isoform-specific substrates have been identified for Akt1 and Akt2,an Akt3-specific substrate is yet to be *** have previously shown that overexpression of Akt3,but not Akt1 or Akt2,plays an essential role in TNBC growth and therapeutic resistance of breast cancer.2 However,the role of Akt3 in TNBC CSCs remains unclear.

关键词： Akt1 breast Akt3

Reviewing electrochemical stability of ionic liquids-/deep eutectic solvents-based electrolytes in lithium-ion,lithium-metal and post-lithium-ion batteries for green and safe energy

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Green Energy & Environment 2024年第6期9卷 966-991页

作者： Yu Chen Shuzi liu Zixin Bi Zheng li Fengyi Zhou Ruifen Shi Tiancheng Mu Department of Chemistry and Material Science Langfang Normal UniversityNO.100 Aimin West RoadLangfangHebei065000China Department of Chemistry Renmin University of ChinNO.59 Zhongguancun StreetHaidian DistrictBeijing100872China

Sustainable energy is the key issue for the environment protection,human activity and economic *** liquids(ILs)and deep eutectic solvents(DESs)are dogmatically regarded as green and sustainable electrolytes in lithium-ion,lithium-metal(e.g.,lithium-sulphur,lithium-oxygen)and post-lithium-ion(e.g.,sodium-ion,magnesium-ion,and aluminum-ion)*** electrochemical stability of ILs/DESs is one of the prerequisites for green,sustainable and safe energy;while easy electrochemical decomposition of ILs/DESs would be contradictory to the concept of green chemistry by adding the cost,releasing volatile/hazardous by-products and hindering the ***,(1)are ILs/DESs-based electrolytes really electrochemically stable when they are not used in batteries?(2)are ILs/DESs-based electrolytes really electrochemically stable in real batteries?(3)how to design ILs/DESs-based electrolytes with high electrochemical stability for batteries to achieve sustainability and green development?Up to now,there is no summary on this topic,to the best of our ***,we review the effect of chemical structure and non-structural factors on the electrochemical stability of ILs/DESs in simulated *** importantly,electrochemical stability of ILs/DESs in real lithium-ion,lithium-metal and post-lithium-ion batteries is concluded and ***,the strategies to improve the electrochemical stability of ILs/DESs in lithium-ion,lithium-metal and post-lithium-ion batteries are *** review would provide a guide to design ILs/DESs with high electrochemical stability for lithium-ion,lithium-metal and postlithium-ion batteries to achieve sustainable and green energy.

关键词： Green solvents Decomposition Sustainable chemistry lithium-oxygen batteries lithium-sulphur batteries Sodium-ion batteries

三方Cr_(5)Te_(8)的磁结构和反常热膨胀

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金属学报 2024年第8期60卷 1150-1154页

作者：任卫军安萌高飞罗小华李昺张志东王进威中国科学院金属研究所沈阳材料科学国家研究中心沈阳110016 中国科学技术大学材料科学与工程学院沈阳110016 Australian Nuclear Science and Technology Organisation New Illawarra RoadLucas HeightsNSW 2234Australia

很多二元Cr-Te化合物具有NiAs结构,其中金属Cr原子出现不同程度的有序缺位。Cr_(5)Te_(8)有三方和单斜2种结构,本工作采用粉末X射线和中子衍射结合Rietveld全谱拟合,确定了用自助溶剂生长的三方Cr_(5)Te_(8)单晶具有P3m1晶体结构,点阵参... 详细信息

很多二元Cr-Te化合物具有NiAs结构,其中金属Cr原子出现不同程度的有序缺位。Cr_(5)Te_(8)有三方和单斜2种结构,本工作采用粉末X射线和中子衍射结合Rietveld全谱拟合,确定了用自助溶剂生长的三方Cr_(5)Te_(8)单晶具有P3m1晶体结构,点阵参数a=0.3900 nm,c=0.5986 nm。粉末中子衍射实验揭示Cr_(5)Te_(8)是磁矩沿c方向的共线铁磁化合物,a方向具有小的负热膨胀,c方向显示正常热膨胀。以最低温3.3 K为参考温度点,在3.3~300 K温度范围内,a方向平均热膨胀系数为-10.7×10^(-6)K^(-1),c方向平均膨胀系数为52.4×10^(-6)K^(-1)。[101]、[302]和[201]取向的Cr_(5)Te_(8)具有近零热膨胀,具备应用前景。Cr_(5)Te_(8)的反常热膨胀与其磁有序没有明显关联,可能与晶格中存在大量的Cr空位有关。

关键词：粉末中子衍射负热膨胀磁结构

Self-confocal NIR-II fluorescence microscopy for multifunctional in vivo imaging

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 105-119页

作者： Jing Zhou Tianxiang Wu Runze Chen liang Zhu Hequn Zhang Yifei li liying Chen Jun Qian State Key Laboratory of Modern Optical Instrumentations Centre for Optical and Electromagnetic ResearchCollege of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityHangzhou 310058P.R.China Dr.li Dak Sum&Yip Yio chin Center for Stem Cell and Regenerative Medicine Zhejiang UniversityHangzhou 310058P.R.China College of Biomedical Engineering and Instrument Science Interdisciplinary Institute of Neuroscience and Technology(ZIINT)Zhejiang UniversityHangzhou 310027P.R.China

Fluorescence imaging in the second near-infrared window(NIR-II,900–1880 nm)with less scattering background in biological tissues has been combined with the confocal microscopic system for achieving deep in vivo imaging with high spatial ***,the traditional NIR-IIfluorescence confocal microscope with separate excitation focus and detection pinhole makes it possess low confocal e±ciency,as well as di±cultly to *** types of upgraded NIR-IIfluorescence confocal microscopes,sharing the same pinhole by excitation and emission focus,leading to higher confocal e±ciency,are built in this *** type is-ber-pinhole-based confocal microscope applicable to CW laser *** is constructed forfluorescence intensity imaging with large depth,high stabilization and low cost,which could replace multiphotonfluorescence microscopy in some applications(e.g.,cerebrovascular and hepatocellular imaging).The other type is air-pinhole-based confocal microscope applicable to femtosecond(fs)laser *** can be employed not only for NIR-IIfluorescence intensity imaging,but also for multi-channelfluorescence lifetime imaging to recognize different structures with similarfluorescence ***,it can be facilely combined with multiphotonfluorescence microscopy.A single fs pulsed laser is utilized to achieve up-conversion(visible multiphotonfluorescence)and down-conversion(NIR-II one-photonfluorescence)excitation simultaneously,extending imaging spectral channels,and thus facilitates multi-structure and multi-functional observation.

关键词： Self-confocal fiber-pinhole air-pinhole multi-channe fluorescence lifetime imaging multi-color imaging

Room-temperature synthesis of full-component APbX_(3)perovskite nanocrystal inks for optoelectronic applications

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Journal of Energy Chemistry 2024年第5期92卷 87-94页

作者： Xinyu Zhao Du li Xuliang Zhang Hehe Huang Chenyu Zhao Wanli Ma Jianyu Yuan Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123JiangsuChina Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices Soochow UniversitySuzhou 215123JiangsuChina Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123JiangsuChin

Lead halide perovskite nanocrystals(PNCs)have received great research interests due to their excellent optoelectronic ***,high temperature,inert gas protection and insulating long-chain ligands are used during the conventional hot-injection synthesis of PNCs,which limits their practical *** this work,we first develop a simple and scalable polar-solvent-free method for the preparation of full-component APbX_(3)(A=Cs,methylammonium(MA),formamidinium(FA),X=Cl,Br,I)PNCs under ambient *** an exothermic reaction between butylamine(BA)and propionic acid(PA)short ligands,the PbX_(2) precursors could be well dissolved without use of any polar ***,the relatively lower growth rate of PNCs in our room-temperature reaction enables us to modulate the synthetic procedure to enhance the scalability(40-fold)and achieve large-scale *** resultant short ligands passivated PNC inks are compatible with varying solution depositing technique like spray coating for large-area ***,we showcase that adopting the as-prepared MAPbI_(3) PNC inks,a self-powered photodetector is fabricated and shows a high *** results demonstrate that our ambient-condition synthetic approach can accelerate the preparation of tunable and ready-to-use PNCs towards commercial optoelectronic applications.

关键词： Room-temperaturesynthesis Perovskite nanocrystals Short-chainligands Large-scale Photodetector

Does the Hartman effect exist in triangular barriers

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chinese Physics B 2024年第3期33卷 214-230页

作者：李青玲郑爽肖智 Department of Mathematics and Physics North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000Chin

We study the phase,Larmor and dwell times of a particle scattered off triangular barriers(TBs).It is interesting that the dependences of dwell,reflective phase and Larmor times on the wave number,barrier width and height for a pair of mirror-symmetric(MS)exact triangular barriers(ETBs)are quite different,as the two ETBs have quite distinct scattering *** comparison,the dependence of the transmitted phase or Larmor times is exactly the same,since the transmitted amplitudes are the same for a pair of MS *** further study the Hartman effect by defining the phase and Larmor velocities associated with the phase and Larmor *** find no barrier width saturation effect for the transmitted and reflected *** is indicated by the fact that all the velocities approach finite constants that are much smaller than the speed of light in vacuum for TBs with positive-slope impact *** for ETBs with vertical left edges,the naive velocities seem to also indicate the absence of the Hartman *** are quite distinct from rectangular barriers and may shed new light on the clarification of the tunneling time issues.

关键词： triangular barrier Hartman effect