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Oscillating paramagnetic Meissner effect and Berezinskii-Kosterlitz-Thouless transition in underdoped Bi2Sr2CaCu2O8+δ

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National Science Review 2024年第5期11卷 142-152页

作者： Shiyuan Wang Yijun Yu Jinxiang Hao Keyi Liang Bingke Xiang Jinjiang Zhu Yishi Lin Yinping Pan Genda Gu Kenji Watanabe Takashi Taniguchi yang Qi Yuanbo zhang Yihua Wang State Key Laboratory of Surface Physics and Department of Physics Fudan University Condensed Matter Physics and Materials Science Department Brookhaven National Laboratory Research Center for Functional Materials National Institute for Materials Science International Center for Materials Nanoarchitectonics National Institute for Materials Science Shanghai Research Center for Quantum Sciences

Superconducting phase transitions in two dimensions lie beyond the description of the Ginzburg-Landau symmetry-breaking paradigm for three-dimensional *** are Berezinskii-KosterlitzThouless（BKT） transitions of paired-electron condensate driven by the unbinding of topological excitations,*** recently discovered monolayers of layered high-transition-temperature（TC）cuprate superconductor Bi2Sr2CaCu2O8+δ（Bi2212） meant that this 2D superconductor promised to be ideal for the study of unconventional *** inhomogeneity posed challenges for distinguishing BKT physics from charge correlations in this ***,we utilize the phase sensitivity of scanning superconducting quantum interference device microscopy susceptometry to image the local magnetic response of underdoped Bi2212 from the monolayer to the bulk throughout its phase *** monolayer segregates into domains with independent phases at elevated temperatures below *** a single domain,we find that the susceptibility oscillates with flux between diamagnetism and paramagnetism in a Fraunhofer-like pattern up to *** finite modulation period,as well as the broadening of the peaks when approaching Tc from below,suggests well-defined vortices that are increasingly screened by the dissociation of vortex-antivortex plasma through a BKT *** the multilayers,the susceptibility oscillation differs in a small temperature regime below TC,consistent with a dimensional crossover led by interlayer *** as strong evidence for BKT transition in the bulk,we observe a sharp jump in phase stiffness and paramagnetism at small fields just below *** results unify the superconducting phase transitions from the monolayer to the bulk underdoped Bi2212,and can be collectively referred to as the BKT transition with interlayer coupling.

关键词： cuprate superconductor monolayer Berezinskii-Kosterlitz-Thouless transition scanning SQUID paramagnetic Meissner effect

基于光谱增强技术实现对532 nm波长激光频率标定

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物理学报 2024年第9期73卷 116-124页

作者：赵瀚宇曹士英戴少阳杨涛左娅妮胡明列天津大学精密仪器与光电子工程学院教育部光电子信息技术重点实验室天津300072 中国计量科学研究院时间频率计量科学研究所北京100029 中国计量科学研究院国家市场监管重点实验室(时间频率与重力计量基准)北京100029

碘稳频532 nm Nd:YAG激光器在复现长度单位“米(m)”、绝对重力测量、引力波探测、精密光谱学、长度计量等领域有着重要应用,对其进行频率测量和标定对于激光器的性能评价具有重要意义.本文采用自行研制的掺Er光纤光学频率梳作为光源,... 详细信息

碘稳频532 nm Nd:YAG激光器在复现长度单位“米(m)”、绝对重力测量、引力波探测、精密光谱学、长度计量等领域有着重要应用,对其进行频率测量和标定对于激光器的性能评价具有重要意义.本文采用自行研制的掺Er光纤光学频率梳作为光源,对其扩谱后的1μm波段进行光谱增强并结合倍频晶体将光学频率梳输出的1.5μm波段光脉冲扩展到532 nm波段.其中掺Er光纤光学频率梳输出功率20 mW,首先经过掺Er光纤放大器将功率提到370 mW,经过脉冲压缩后脉冲宽度为45.7 fs,此后经过高非线性光纤扩谱实现光谱覆盖至1μm,输出功率为180 mW.扩谱后的1μm波段激光经过掺Yb光纤放大器放大至601 mW,经过压缩后脉冲宽度为84.6 fs,压缩后功率为420 mW.采用MgO:PPLN晶体对压缩后激光进行倍频得到155 mW的532 nm激光,倍频效率为36%.利用该系统分别对碘稳频532 nm Nd:YAG激光器输出的基频光1064 nm和倍频光532 nm进行拍频,获得了优于40 dB信噪比的拍频信号,后续进行了超过10 h的连续测量,测量结果与国际推荐值保持一致.

关键词：光谱增强频率测量稳频激光光学频率梳

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Brachiopods from the Silurian “Lower Red Beds” of Wuhan（E. Hubei， South China）: paleoecological and paleogeographical implications

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Journal of Earth Science 2024年

作者： Jia-Yi Yin Yi-Long liu lie-Bin Huang Yi-Ming Gong Rui-Wen Zong School of Earth Sciences， China University of Geosciences Faculty of Land and Resources Engineering， Kunming University of Science and Technology State Key Laboratory of Biogeology and Environmental Geology， China University of Geosciences

The age and sedimentary environment of the Silurian “Lower Red Beds” (LRBs)， which occur widely in South China， have long been controversial because of the scarcity of index fossils. Recently， these beds have been dated by trilobites as middle-late Aeronian to early Telychian in age. Here， we report abundant brachiopods from the LRBs in Wuhan， Middle yangtze Region， including atrypides (Meifodia hunanensis， Zygospiraella sp. 1， Zygospiraella sp. 2 and Nalivkinia? sp.)， spiriferides (Striispirifer acuminiplicatus， Striispirifer? sp.)， strophomenides (Eostropheodonta? sp. and Katastrophomena modesta)， and linguliformeans (Anomaloglossa? sp. and Orbiculoidea? sp.). Most of these are common in the Leijiatun， Xiangshuyuan， Shihniulan， Niuchang， Lojoping， and Shamao formations in the Upper yangtze Region. The discovery of brachiopods from the LRBs in Wuhan not only enrich the biodiversity of the LRBs in the yangtze Region， where Meifodia， Zygospiraella， Katastrophomena and Eostropheodonta are first found in the LRBs， but also expand the paleogeographical distribution of brachiopods to Middle-Lower yangtze Region that first radiated after the end-Ordovician extinction. In addition， this brachiopod fauna also provides important implications for the sedimentary environment of LRBs during the Llandovery， which is usually developed in the nearshore shallow-water (BA1-2)， althought this paper extends to the deeper parts of the shallow-marine (BA3-4).

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适应新型电力系统的继电保护综合评价方法

电网技术 2024年第4期48卷 1633-1644,I0074页

作者：张烈郭鹏李仲青张瀚方闫周天康逸群电网安全与节能国家重点实验室(中国电力科学研究院有限公司) 北京市海淀区100192

我国新型电力系统安全可靠运行高度依赖第一道防线的继电保护设备,综合评判继电保护运行水平具有重要意义。针对继电保护构造复杂、运行状态影响因素多以及不同评价指标权重确定难题,该文在充分借鉴现有运行评价指标的基础上,提出了装... 详细信息

我国新型电力系统安全可靠运行高度依赖第一道防线的继电保护设备,综合评判继电保护运行水平具有重要意义。针对继电保护构造复杂、运行状态影响因素多以及不同评价指标权重确定难题,该文在充分借鉴现有运行评价指标的基础上,提出了装备水平、运行状态、维修性、保障性和专业管理规范性5方面评价要素,并基于构型理论掌握了不同要素间的关系,通过支持向量机剔除了冗余指标,得出继电保护综合评价体系。在主观赋权与客观赋权结果基础上,应用样本评价结果序列的正态分布拟合优度,提出了对加法合成、乘法合成的组合系数进行优化的方法,使主、客观信息达到统一。继电保护综合评价指标体系的构建以及指标权重的科学计算为继电保护运行管理提供重要参考依据。

关键词：继电保护综合评价构型理论支持向量机拟合优度

Embedding Tensors on 3-Hom-lie Algebras

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Journal of Mathematical Research with Applications 2024年第2期44卷 187-198页

作者： Wen TENG Jiulin JIN Yu zhang School of Mathematics and Statistics Guizhou University of Finance and Economics School of Science Guiyang University

In this paper, we introduce the notion of embedding tensors on 3-Hom-lie algebras and show that embedding tensors induce naturally 3-Hom-Leibniz algebras. Moreover, the cohomology theory of embedding tensors on 3-Hom-lie algebras is defined. As an application,we show that if two linear deformations of an embedding tensor on a 3-Hom-lie algebra are equivalent, then their infinitesimals belong to the same cohomology class in the first cohomology group.

关键词： 3-Hom-lie algebra embedding tensor representation cohomology deformation

Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage

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Neural Regeneration Research 2024年第4期19卷 825-832页

作者： Jiatong zhang Qi Zhu Jie Wang Zheng Peng Zong Zhuang Chunhua Hang Wei Li Department of Neurosurgery Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing University Department of Neurosurgery Nanjing Drum Tower HospitalClinical College of Nanjing Medical University

The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood *** are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial *** mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging *** response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological *** interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid *** review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control *** also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage.

关键词： mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction mitochondrial fission and fusion mitochondrial quality control mitophagy subarachnoid hemorrhage

Gifted Students’Special Educational Programs in France:An Analysis of Students’Needs as Perceived by Headmasters-A Secondary Publication

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Journal of Contemporary Educational Research 2024年第4期8卷 316-327页

作者： Karine Buard Minna Puustinen Amélie Courtinat-Camps Research Group on Disability AccessibilityEducational and School Practices(GRHAPES)INSHEAFrance Developmental and Educational Psychology “Psychology of Socialisation-Development and Work”Laboratory(LPS-DT)Toulouse Jean Jaurès UniversityFrance

Some French public middle schools offer gifted students the opportunity to pursue their education in general classes,while benefiting from specific facilities within the framework of a dedicated educational *** this study,we sought to identify and analyze the needs of these students as perceived by the headmaster of each middle school *** results highlight two main student needs,common to all these programs(uneasiness and difficulties in peer relationships)as well as needs specifically mentioned by some headmasters(non-adaptive behavior).

关键词： Learning difficulties Students in difficulty Education policies

Lithium-Ion Charged Polymer Channels Flattening Lithium Metal Anode

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Nano-Micro Letters 2024年第4期16卷 379-393页

作者： Haofan Duan Yu You Gang Wang Xiangze Ou Jin Wen Qiao Huang Pengbo Lyu Yaru Liang Qingyu Li Jianyu Huang Yun‑Xiao Wang Hua‑Kun liu Shi Xue Dou Wei‑hong Lai Hunan Provincial Key Laboratory of Thin Film Materials and Devices School of Material Sciences and EngineeringXiangtan UniversityXiangtan 411105People’s Republic of China Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemical and Pharmaceutical ScienceGuangxi Normal UniversityGuilin 541004People’s Republic of China Institute for Superconducting and Electronic Materials Australian Institute of Innovative MaterialsUniversity of WollongongInnovation CampusSquires WayNorth WollongongNSW 2500Australia Institute of Energy Materials Science University of Shanghai for Science and TechnologyShanghai 200093People’s Republic of China

The concentration difference in the near-surface region of lithium metal is the main cause of lithium dendrite *** this issue will be key to achieving high-performance lithium metal batteries(LMBs).Herein,we construct a lithium nitrate(LiNO_(3))-implanted electroactiveβphase polyvinylidene fluoride-co-hexafluoropropylene(PVDF-HFP)crystalline polymorph layer(PHL).The electronegatively charged polymer chains attain lithium ions on the surface to form lithium-ion charged *** channels act as reservoirs to sustainably release Li ions to recompense the ionic flux of electrolytes,decreasing the growth of lithium *** stretched molecular channels can also accelerate the transport of Li *** combined effects enable a high Coulombic efficiency of 97.0%for 250 cycles in lithium(Li)||copper(Cu)cell and a stable symmetric plating/stripping behavior over 2000 h at 3 mA cm^(-2)with ultrahigh Li utilization of 50%.Furthermore,the full cell coupled with PHL-Cu@Li anode and Li Fe PO_(4) cathode exhibits long-term cycle stability with high-capacity retention of 95.9%after 900 ***,the full cell paired with LiNi_(0.87)Co_(0.1)Mn_(0.03)O_(2)maintains a discharge capacity of 170.0 mAh g^(-1)with a capacity retention of 84.3%after 100 cycles even under harsh condition of ultralow N/P ratio of *** facile strategy will widen the potential application of LiNO_(3)in ester-based electrolyte for practical high-voltage LMBs.

关键词： Polymer ionic channel Li metal batteries Artificial protective layer Uniform Li deposition Electrochemical performances

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基于标签注意力与多粒度网络的层级专利分类

计算机工程与设计 2024年第10期45卷 3074-3080页

作者：廖列法张燕琴江西理工大学信息工程学院江西赣州341000 江西现代职业技术学院院长办公室江西南昌330095

针对中文专利的多层级自动分类任务中不同层级之间标签丰富语义信息及依赖关系和不同粒度大小的特征信息被忽略问题,提出一种RoBERTa-ALMG模型。通过RoBERTa预训练模型获取专利文本的高级语义表征,在标签注意力模块中借助双重多层感知... 详细信息

针对中文专利的多层级自动分类任务中不同层级之间标签丰富语义信息及依赖关系和不同粒度大小的特征信息被忽略问题,提出一种RoBERTa-ALMG模型。通过RoBERTa预训练模型获取专利文本的高级语义表征,在标签注意力模块中借助双重多层感知机和注意力机制动态生成标签文本向量表示,通过前向传播过程实现不同层级之间的知识传递与信息共享,借助多粒度特征抽取模块捕捉层级之间的不同粒度特征和信息。在国家信息中心公布的数据集上的实验结果表明,该模型的表现优于其它模型。

关键词：专利分类层级分类预训练模型标签注意力多粒度特征抽取特征信息信息共享