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More Catastrophic Flow Events may Follow the Chamoli Rock and Ice Avalanche under Climate Change

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Journal of Earth Science 2024年第4期35卷 1382-1384页

作者： Haijun Qiu Ya Liu Bingzhe Tang Ninglian Wang Jiading Wang Shaanxi Key Laboratory of Earth surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi’an 710127China Institute of Earth surface System and Hazards Northwest UniversityXi’an 710127China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China

0 INTRODUCTION Global warming not only exacerbates the instability of the climate system,causing more weather extremes but also has far-reaching impacts on surface systems,changing disaster environments(Qiu et al.,2024;Ye et al.,2024).The key medium between climate warming and the mountain environment is the cryosphere,whose recession increases the occurrence of chain disasters such as rock-ice avalanches and other flow events(Yang et al.,2023).

关键词： warming disaster climate

Universal Machine Learning Kohn–Sham Hamiltonian for Materials

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Chinese Physics Letters 2024年第7期41卷 95-110页

作者：钟阳于宏宇杨吉辉郭星宇向红军龚新高 Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface Physicsand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Qi Zhi Institute Shanghai 200030China

While density functional theory(DFT)serves as a prevalent computational approach in electronic structure calculations,its computational demands and scalability limitations ***,leveraging neural networks to parameterize the Kohn-Sham DFT Hamiltonian has emerged as a promising avenue for accelerating electronic structure *** advancements,challenges such as the necessity for computing extensive DFT training data to explore each new system and the complexity of establishing accurate machine learning models for multi-elemental materials still *** these hurdles,this study introduces a universal electronic Hamiltonian model trained on Hamiltonian matrices obtained from first-principles DFT calculations of nearly all crystal structures on the Materials *** demonstrate its generality in predicting electronic structures across the whole periodic table,including complex multi-elemental systems,solid-state electrolytes,Moir´e twisted bilayer heterostructure,and metal-organic ***,we utilize the universal model to conduct high-throughput calculations of electronic structures for crystals in GNoME datasets,identifying 3940 crystals with direct band gaps and 5109 crystals with flat *** offering a reliable efficient framework for computing electronic properties,this universal Hamiltonian model lays the groundwork for advancements in diverse fields,such as easily providing a huge data set of electronic structures and also making the materials design across the whole periodic table possible.

关键词： Hamiltonian utilize twisted

Life forms affect beta-diversity patterns of larch forests in China

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Plant Diversity 2024年第1期46卷 49-58页

作者： Wenjing Fang Qiong Cai Chengjun Ji Jiangling Zhu Zhiyao Tang Jingyun Fang School of Ecology and Environmental Science Yunnan UniversityKunming 650091China department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Beta-diversity reflects the spatial changes in community species composition which helps to understand how communities are assembled and biodiversity is formed and maintained. Larch(Larix) forests, which are coniferous forests widely distributed in the mountainous and plateau areas in North and Southwest China, are critical for maintaining the environmental conditions and species diversity. Few studies of larch forests have examined the beta-diversity and its constituent components(species turnover and nestedness-resultant components). Here, we used 483 larch forest plots to determine the total betadiversity and its components in different life forms(i.e., tree, shrub, and herb) of larch forests in China and to evaluate the main drivers that underlie this beta-diversity. We found that total betadiversity of larch forests was mainly dependent on the species turnover component. In all life forms,total beta-diversity and the species turnover component increased with increasing geographic, elevational, current climatic, and paleoclimatic distances. In contrast, the nestedness-resultant component decreased across these same distances. Geographic and environmental factors explained 20%-25% of total beta-diversity, 18%-27% of species turnover component, and 4%-16% of nestedness-resultant component. Larch forest types significantly affected total beta-diversity and species turnover component. Taken together, our results indicate that life forms affect beta-diversity patterns of larch forests in China, and that beta-diversity is driven by both niche differentiation and dispersal limitation. Our findings help to greatly understand the mechanisms of community assemblies of larch forests in China.

关键词： Beta-diversity Species turnover Nestedness-resultant Geographic distance Climatic distance Larch forest

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

Spatial search weighting information contained in cell velocity distribution

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Chinese Physics B 2024年第2期33卷 522-528页

作者：马一凯李娜陈唯 State Key Laboratory of surface Physics and department of Physics Fudan UniversityShanghai 200438China China National Center for Bioinformation Beijing 100101China National Genomics Data Center Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China

Cell migration plays a significant role in physiological and pathological *** the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell *** of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive *** article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire *** confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is *** simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial ***,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search *** simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search ***,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell *** results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication.

关键词： cell migration foraging efficiency random walk spatial search weight

Nondestructive Nonlinear Optical Microscopy Revealed the Blackening Mechanism of Ancient Chinese Jades

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Research 2024年第3期2023卷 391-399页

作者： Yaxin Chen Rong Wang Minbiao Ji State Key Laboratory of surface Physics and department of Physics Human Phenome InstituteAcademy for Engineering and TechnologyKey Laboratory of Micro and Nano Photonic Structures(Ministry of Education)Yiwu Research Institute of Fudan UniversityFudan UniversityShanghai 200433China department of Cultural Heritage and Museology Fudan UniversityShanghaiChina

Jade is most valued in Chinese culture since ancient times. For unearthed jade artifacts, the alteration color resulting from weathering effects and human activities provides information for cultural heritage conservation, archaeology, and history. Currently, the noninvasive 3-dimensional characterization of jade artifacts with high chemical and spatial resolution remains challenging. In this work, we applied femtosecond pump–probe microscopy and second harmonic generation microscopy techniques to study the black alteration of an ancient jade artifact of the late Spring and Autumn period (546 to 476 BC). The direct cause of the “mercury alteration” phenomena was discovered to be the conversion of metacinnabar from buried cinnabar in the tomb. Furthermore, a 3-dimensional optical reconstruction of the black alteration was achieved, providing a high-resolution method for analyzing the blackening mechanism without the need of sample damage. Our approach opens up new opportunities to extract microscopic spatiochemical information for a broad range of alteration colors in jade artifacts.

关键词： pump Nonlinear buried

Characteristics of cell motility during cell collision

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Chinese Physics B 2024年第2期33卷 72-77页

Quantitative examination of cellular motion and intercellullar interactions possesses substantial relevance for both biology and ***,the effects of intercellular interactions during cellular locomotion remain under-explored in experimental *** such,this study seeks to bridge this research gap,adopting Dictyostelium discoideum(Dicty)cells as a paradigm to investigate variations in cellular motion during reciprocal *** aim to attain a comprehensive understanding of how cell interactions influence cell *** observing and processing the motion trajectories of colliding cells under diverse chemical environments,we calculated the diffusion coefficient(D)and the persistence time(τ),using mean square *** analysis of the relationship dynamics between D andτprior to the collisions reveals intricate and non-monotonic alterations in cell movements during *** quantitatively scrutinizing theτtrend,we were able to categorize the cellular responses to interactions under different ***,we ascertained that the effect of cell interactions during collisions in Dicty cells emulates a classical sigmoid *** discovery suggests that cellular responses might comply with a pattern akin to the Weber–Fechner law.

关键词： cell migration random walk cell-cell interaction

High-precision nondestructive evaluation of a thermal barrier coating based on perovskite quantum dot anion exchange

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Nano Research 2024年第5期17卷 4582-4592页

作者： Tao Han Shufang Ding Zifan Wang Sirong Jiang Pengjiang Jing Tianshang Yi Yaqi Chen Chunzhi Jiang Xiaofeng Zhang Microelectronics and Optoelectronics Technology Key Laboratory of Hunan Higher Education School of Physics and Electronic Electrical EngineeringXiangnan UniversityChenzhou 423000China National Engineering Laboratory for Modern Materials surface Engineering Technology&The Key Lab of Guangdong for Modern surface Engineering Technology Guangdong Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

Thermal barrier coatings(TBCs)in gas turbine engines are used in expressly harsh environments;thus,assessing TBC integrity status is critical for safety and ***,traditional periodic maintenance involves visual inspections of the TBCs,requiring the gas turbine to be decommissioned and partially *** importantly,tiny defects or internal damages that easily cause coating failure cannot be *** this work,a new nondestructive evaluation(NDE)technique of TBCs based on quantum dot(QD)anion exchange is first explored *** exchanging anions between the Cl ions and the CsPbBr_(3) QDs,the degrees of salt corrosion of the TBCs are *** resultant NDE technique shows that the colour of the TBCs obviously changes from green to blue,accompanied by a large blueshift(~100 nm)of the photoluminescence(PL)peak *** addition,the relationship between the PL peak position and coating thermophysical properties indicates that the precision of this NDE technique may easily identify theμm-level of the thermal growth oxide(TGO)changes inside the TBCs.

关键词： thermal barrier coatings nondestructive evaluation CsPbBr_(3)quantum dot anion exchange thermal growth oxide

Comparative Study of the Effects of Nano ZnO and CuO on the Biodegradation,Biocompatibility,and Antibacterial Properties of Micro-arc Oxidation Coating of Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 242-254页

作者： Ying Shen Xianfeng Shan Iniobong P.Etim Muhammad Ali Siddiqui Yang Yang Zewen Shi Xuping Su Junxiu Chen Key Laboratory of Materials surface Science and Technology of Jiangsu Province Changzhou UniversityChangzhou213164China department of Stomatology The Affiliated Xinhua Hospital of Dalian UniversityDalian116000China department of Physics University of CalabarCalabar540242Nigeria Metallurgical Engineering department NED University of Engineering and TechnologyUniversity RoadKarachi75270Pakistan Ningbo No.2 Hospital Ningbo315010China

This research systematically examined the degradation,antibacterial effects,and biocompatibility of micro-arc oxidation(MAO)coatings with nano CuO and ZnO on extruded Mg *** copper(Cu)and Zinc(Zn)possess antibacterial *** findings demonstrated that adding ZnO will appreciably reduce the degradation rate of MAO-coating alloy due to the self-sealing micro ***+MAO coating exhibited excellent antibacterial performance,with an antibacterial rate of over 90%within 6 h co-cultured with Staphylococcus ***,the antibacterial rate of ZnO+MAO coating reached 90%after 12 h *** test using MG63 cell indicated that the incorporation of CuO and ZnO did not notably affect the cell viability rate of the ***,after 14 days of culture,the CuO+MAO and ZnO+MAO coated samples exhibited higher alkaline phosphatase(ALP)activity than the MAO-coated and uncoated samples,suggesting favorable osteogenic properties.

关键词： Copper oxide Zinc oxide Micro-arc oxidation(MAO)coating Corrosion behavior Antibacterial characteristics