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Distinct ultrafast dynamics of bilayer and trilayer nickelate superconductors regarding the density-wave-like transitions

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Science Bulletin 2025年第2期70卷 180-186页

作者： Yidian Li Yantao Cao Liangyang Liu Pai Peng hao lin Cuiying Pei Mingxin Zhang Heng Wu Xian Du Wenxuan Zhao Kaiyi Zhai Xuefeng Zhang Jinkui Zhao Miaoling lin Pingheng Tan Yanpeng Qi Gang Li Hanjie Guo Luyi Yang Lexian Yang State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Key Lab for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China Songshan Lake Materials Laboratory Dongguan 523808China School of Physical Science and Technology ShanghaiTech University and CAS-Shanghai Science Research CenterShanghai 201210China State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China ShanghaiTech Laboratory for Topological Physics Shanghai 200031China Laboratory of High-resolution Electron Microscopy ShanghaiTech UniversityShanghai 201210China Frontier Science Center for Quantum Information Beijing 100084China

In addition to the pressurized high-temperature superconductivity,bilayer and trilayer nickelate superconductors La_(n+1)Ni_nO_(3n+1)(n=2 and 3)exhibit many intriguing properties at ambient pressure,such as orbital-dependent electronic correlation,non-Fermi liquid behavior,and density-wave ***,using ultrafast reflectivity measurement,we observe a drastic difference between the ultrafast dynamics of the bilayer and trilayer nickelates at ambient *** observe a coherent phonon mode in La_(4)Ni_(3)O_(10)involving the collective vibration of La,Ni,and O atoms,which is absent in La_(3)Ni_(2)O_(7).Temperature-dependent relaxation time diverges near the density-wave transition temperature of La_(4)Ni_(3)O_(10),while it is inversely proportional to the temperature in La_(3)Ni_(2)O_(7)above~150 K,suggesting a non-Fermi liquid behavior of La_(3)Ni_(2)O_(7).Moreover,we estimate the electron–phonon coupling constants to be 0.05–0.07 and 0.12–0.16 for La_(3)Ni_(2)O_(7)and La_(4)Ni_(3)O_(10),respectively,suggesting a relatively minor role of electron–phonon coupling in the electronic properties of La_(n+1)Ni_nO_(3n+1)at ambient *** relevant microscopic interaction and dynamic information are essential for further studying the interplay between superconductivity and density-wave transitions in nickelate superconductors.

关键词： Nickelate superconductors Density-wave state Ultrafast dynamics Electron-phonon coupling Coherent phonon

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无机盐对有机融雪剂改性效果研究

北方交通 2025年第1期 84-86页

作者：林浩山西省交通科技研发有限公司太原市030032

将氯化钠、氯化钙、氯化镁与乙二醇按照3∶7的质量比进行混合,对比纯乙二醇情形,分析受环境温度影响下的降温速度及凝固点温度变化规律,为不同环境下应用无机盐改性处理乙二醇提供参考。结果表明,加入氯化钠后乙二醇降温速度最慢,加入... 详细信息

将氯化钠、氯化钙、氯化镁与乙二醇按照3∶7的质量比进行混合,对比纯乙二醇情形,分析受环境温度影响下的降温速度及凝固点温度变化规律,为不同环境下应用无机盐改性处理乙二醇提供参考。结果表明,加入氯化钠后乙二醇降温速度最慢,加入氯化镁后乙二醇降温速度最快;加入氯化钙降低乙二醇凝固点的效果最好,而加入氯化镁降低乙二醇凝固点的效果较差。

关键词：融雪剂氯化物乙二醇凝固点

Dirac-vortex topological photonic crystal fibre

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Light(Science & Applications) 2020年第1期9卷 24-30页

作者： hao lin ling Lu Institute of Physics Chinese Academy of Sciences/Beijing National Laboratory for Condensed Matter PhysicsBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan523808 GuangdongChina

The success of photonic crystal fibres relies largely on the endless variety of two-dimensional photonic crystals in the ***,we propose a topological bandgap fibre whose bandgaps along in-plane directions are opened by generalised Kekulémodulation of a Dirac lattice with a vortex ***,the existence of mid-gap defect modes is guaranteed to guide light at the core of this Dirac-vortex fibre,where the number of guiding modes equals the winding number of the spatial *** single-vortex design provides a single-polarisation single-mode for a bandwidth as large as one octave.

关键词： fibre vortex crystal

Non-fullerene small molecule electron acceptors for high-performance organic solar cells

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Journal of Energy Chemistry 2018年第4期27卷 990-1016页

作者： hao lin Qiang Wang Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and Engineering Shaanxi Normal University

Fullerenes and their derivatives are important types of electron acceptor materials and play a vital role in organic solar cell devices. However, the fullerene acceptor material has some difficulties to overcome the intrinsic shortcomings, such as weak absorption in the visible range, difficulty in modification and high cost, which limit the performance of the device and the large-scale application of this type of acceptors. In recent years, non-fullerene electron acceptor material has attracted the attention of scientists due to the advantages of adjustable energy level, wide absorption, simple synthesis, low processing cost and good solubility. Researchers can use the rich chemical means to design and synthesize organic small molecules and their oligomers with specific aggregation morphology and excellent optoelectronic prop- erties. Great advances in the field of synthesis, device engineering, and device physics of non-fullerene acceptors have been achieved in the last few years. At present, non-fullerene small molecules based photovoltaic devices achieve the highest efficiency more than 13% and the efficiency gap between fullerenetype and non-fullerene-type photovoltaic devices is gradually narrowing. In this review, we explore recent progress of non-fullerene small molecule electron acceptors that have been developed and led to highefficiency photovoltaic devices and put forward the prospect of development in the future.

关键词： Organic solar cells Non-fullerene Electron acceptors Bulk heterojunction

A Theorem on the Structure of the Ring A_(cris)

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1333-1336页

作者： hao lin LMAM School of Mathematical SciencesPeking University

In this paper, we give a new description for the structure of the p-adic period subring Acris using formal groups.

关键词： Lubin-Tate formal group crystalline period ring

有机固体废弃物制备腐殖酸及其应用的研究进展

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应用化工 2025年第1期54卷 225-232页

作者：刘成丰穆智贤唐家桓林皓福州大学环境与安全学院福建福州350108 武夷学院生态与资源工程学院福建省生态产业绿色技术重点实验室福建武夷山354300 福建农林大学资源与环境学院福建省土壤环境健康与调控重点实验室福建福州350002

综合分析了有机固体废弃物制备腐殖酸(HA)的制备技术现状、应用进展及未来发展趋势。有机废弃物来源广泛,可通过微生物作用、化学聚合和氧化还原反应转化为腐殖酸。腐殖酸在土壤改良、植物生长促进、环境治理和材料科学等领域中展现出... 详细信息

综合分析了有机固体废弃物制备腐殖酸(HA)的制备技术现状、应用进展及未来发展趋势。有机废弃物来源广泛,可通过微生物作用、化学聚合和氧化还原反应转化为腐殖酸。腐殖酸在土壤改良、植物生长促进、环境治理和材料科学等领域中展现出显著潜力,能有效提升土壤质量、增强植物抗病力,并在废水处理和重金属吸附中发挥作用。然而,制备过程中的能耗、成本及产品标准化是当前面临的主要挑战。未来研究应集中于开发高效、环保的制备技术,同时探索腐殖酸的多功能化和高值化应用,以实现可持续发展。

关键词：有机固体废弃物腐殖酸土壤改良环境治理材料科学

The Minimum Centroid Branch Spanning Tree Problem

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Journal of the Operations Research Society of China 2024年第2期12卷 528-539页

作者： hao lin Cheng He School of Science Henan University of TechnologyZhengzhou450001HenanChina

For a spanning tree T of graph G,the centroid of T is a vertex v for which the largest component of T-v has as few vertices as *** number of vertices of this component is called the centroid branch weight of *** minimum centroid branch spanning tree problem is to find a spanning tree T of G such that the centroid branch weight is *** application to design of communication networks,the loads of all branches leading from the switch center should be as balanced as *** this paper,we prove that the problem is strongly NP-hard even for bipartite ***,the problem is shown to be polynomially solvable for split graphs,and exact formulae for special graph familis,say Kn_(1),n_(2),...,n_(k)and P_(m)×P_(n),are presented.

关键词： Spanning tree optimization Centroid branch-NP-hardness Polynomial-time algorithm

DySnake-YOLO:改进的YOLOv9c电路板表面缺陷检测方法

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计算机工程与应用 2025年第3期61卷 242-252页

作者：李耀龙陈晓林林浩王宇王春林云南师范大学信息学院昆明650500 楚雄师范学院数学与计算机学院云南楚雄675099 琼台师范学院信息科学技术学院海口571100

针对印刷电路板生产时出现缺孔、开路、短路、毛刺和假铜等缺陷,由于缺陷尺寸微小和背景的相似性等问题造成的检测精度低,提出一种改进YOLOv9的电路板表面缺陷检测算法DySnake-YOLO。在特征提取部分,添加了一种动态的、查询感知的稀疏... 详细信息

针对印刷电路板生产时出现缺孔、开路、短路、毛刺和假铜等缺陷,由于缺陷尺寸微小和背景的相似性等问题造成的检测精度低,提出一种改进YOLOv9的电路板表面缺陷检测算法DySnake-YOLO。在特征提取部分,添加了一种动态的、查询感知的稀疏注意力机制BRA,来对印刷电路板的特征进行细粒度的提取。在特征融合部分设计了一种根据管状目标以适应电路板特性,以及关注区域连通性特征适合管状场景的RE4DConv卷积模块,提升了模型融合印刷电路板中的管状尺度特征的能力。通过在北京大学公开的PCB缺陷数据集上进行实验表明,改进后的算法相较于原型,mAP50提高了0.023,与YOLOv8n等主流目标检测算法相比,改进方法在mAP50、mAP50-95方面分别提升了0.071、0.085,在印刷电路板缺陷检测任务上的有着较高的应用价值。

关键词：目标检测电路板检测 YOLOv9 BRA模块 RE4DConv

On Fixed-Parameter Solvability of the Minimax Path Location Problem

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Communications on Applied Mathematics and Computation 2023年第4期5卷 1644-1654页

作者： hao lin Cheng He School of Science Henan University of TechnologyZhengzhou450001HenanChina

The minimax path location problem is to find a path P in a graph G such that the maximum distance d_(G)(v,P)from every vertex v∈V(G)to the path P is *** is a well-known NP-hard problem in network *** paper studies the fixed-parameter solvability,that is,for a given graph G and an integer k,to decide whether there exists a path P in G such that max v∈V(G)d_(G)(v,P)≤*** the answer is affirmative,then graph G is called *** show that this decision problem is NP-complete even for k=*** the other hand,we characterize the family of 1-path-eccentric graphs,including the traceable,interval,split,permutation graphs and ***,some polynomially solvable special graphs are discussed.

关键词： Discrete location Path location Fixed-parameter solvability Graph characterization Polynomial-time algorithm