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Interplay between the atomic structures and superconductivity of two-monolayer Pb films

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 90-98页

作者： Kun Xie Ze Huang Pengju Li yumin Xia Desheng Cai Yitong Gu Yuzhou Liu Fangliang Cai Runxiao Zhang Haohao Shi Ping Cui Shengyong Qin International Center for Quantum Design of Functional Materials(ICQD) University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Superconductors with reduced dimensionality have been widely explored for their exotic superconducting ***,at the two-dimensional limit,two-monolayer Pb films with two types of structures provide an ideal platform to unveil the underlying superconducting mechanism[Science 324,1314(2009)].Here,by combining scanning tunneling microscopy(STM)with the first-principle calculations,we successfully identify that these two types have different atomic lattice structures with varying stacking phases,which further enables us to calculate the phonon spectrum and electron phonon coupling strength of each *** theoretical calculations are in good agreement with tunneling spectroscopy measurements of the superconducting transition temperatures(T_(c)),which established a correlation between atomic structures and ***,it was observed that the higher T_(c)of these two types also possess higher out-of-plane upper critical magnetic fields(Hc2).These findings will provide important new insights into two-dimensional superconductivity at the atomic level.

关键词： 2 ML Pb films superconductivity atomic structure scanning tunneling microscopy first-principle calculations

Consecutive narrow and broad quasi-periodic fast-propagating wave trains associated with a flare

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 200-211页

作者： Xinping zhou Yuandeng Shen Chengrui zhou Zehao Tang Ahmed Ahmed Ibrahim College of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610068China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Department of Physics and Astronomy College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

The excitation mechanism of coronal quasi-period fast-propagating(QFP)wave trains remains *** Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory observations,we study a narrow and a broad QFP wave trains excited one after another during the successive eruptions of filaments hosted within a fan-spine magnetic system on October 20,*** consecutive occurrence of these two types of QFP wave trains in the same event provides an excellent opportunity to explore their excitation mechanisms and compare their physical *** observational results reveal that narrow and broad QFP wave trains exhibit distinct speeds,periods,energy fluxes,and relative intensity amplitudes,although originating from the same active region and being associated with the same GOES C2.9 *** wavelet analysis,we find that the narrow QFP wave train shares a similar period with the flare itself,suggesting its possible excitation through the pulsed energy release in the magnetic reconnection process that generated the accompanying *** the other hand,the broad QFP wave train appears to be associated with the energy pulses released by the successive expansion and unwinding of filament ***,it is plausible that the broad QFP wave train was also excited by the sequential stretching of closed magnetic field lines driven by the erupting *** findings shed light on the different excitation mechanisms and origins of the QFP wave trains.

关键词： narrow wave excitation

Efficient Penetration Testing Path Planning Based on Reinforcement Learning with Episodic Memory

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2613-2634页

作者： Ziqiao zhou Tianyang zhou Jinghao Xu Junhu Zhu Henan Key Laboratory of Information Security National Engineering Technology Research Center of the Digital Switching SystemZhengzhou450000China School of Cryptographic Engineering Information Engineering UniversityZhengzhou450000China

Intelligent penetration testing is of great significance for the improvement of the security of information systems,and the critical issue is the planning of penetration test *** view of the difficulty for attackers to obtain complete network information in realistic network scenarios,Reinforcement Learning(RL)is a promising solution to discover the optimal penetration path under incomplete information about the target *** RL-based methods are challenged by the sizeable discrete action space,which leads to difficulties in the ***,most methods still rely on experts’*** address these issues,this paper proposes a penetration path planning method based on reinforcement learning with episodic ***,the penetration testing problem is formally described in terms of reinforcement *** speed up the training process without specific prior knowledge,the proposed algorithm introduces episodic memory to store experienced advantageous strategies for the first ***,the method offers an exploration strategy based on episodic memory to guide the agents in *** design makes full use of historical experience to achieve the purpose of reducing blind exploration and improving planning ***,comparison experiments are carried out with the existing RL-based *** results reveal that the proposed method has better convergence *** running time is reduced by more than 20%.

关键词： Intelligent penetration testing penetration testing path planning reinforcement learning episodic memory exploration strategy

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金叶榆抗逆性研究进展

林业与环境科学 2018年第1期34卷 112-115页

作者：周玉敏湖北生态工程职业技术学院湖北武汉430200

金叶榆(Ulmus pumila‘Jinye’)是我国具有自主知识产权的彩叶植物树种,不仅观赏价值高,且生长迅速、耐强度修剪、抗逆性强,为我国寒冷、干旱及盐碱地区提供了一个乔灌皆宜的优良彩叶植物新品种。分别从金叶榆的抗寒性、抗旱性、抗涝性... 详细信息

金叶榆(Ulmus pumila‘Jinye’)是我国具有自主知识产权的彩叶植物树种,不仅观赏价值高,且生长迅速、耐强度修剪、抗逆性强,为我国寒冷、干旱及盐碱地区提供了一个乔灌皆宜的优良彩叶植物新品种。分别从金叶榆的抗寒性、抗旱性、抗涝性、抗盐碱性以及光胁迫对其叶色的影响等方面进行总结,概述了金叶榆抗逆性研究的意义、近年来的研究进展,并总结了当前研究的侧重点。最后指出,金叶榆是研究金色叶形成机理的良好材料,目前其抗逆性在分子和基因层面的研究还有待发掘,开展研究可为金叶榆的推广应用提供理论依据。

关键词：金叶榆抗逆性抗寒性抗旱性耐水涝耐盐碱

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《1852年上海年鉴》编译说明

上海地方志 2019年第1期 49-52,95页

作者：周育民上海师范大学

作为上海历史上的第一本年鉴:《1852年上海年鉴》保留了许多上海开埠初期历史的重要信息,涉及天文地理、自然科学及社会科学等各个方面,本文着重介绍其中几篇有代表性的文章。此外,还介绍了几篇涉及上海以外(宁波、土耳其、澳大利亚)内... 详细信息

作为上海历史上的第一本年鉴:《1852年上海年鉴》保留了许多上海开埠初期历史的重要信息,涉及天文地理、自然科学及社会科学等各个方面,本文着重介绍其中几篇有代表性的文章。此外,还介绍了几篇涉及上海以外(宁波、土耳其、澳大利亚)内容的文章。

关键词： 1852年上海年鉴编译说明

Spatial Distribution Feature Extraction Network for Open Set Recognition of Electromagnetic Signal

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 279-296页

作者： Hui Zhang Huaji zhou Li Wang Feng zhou The Ministry Key Laboratory of Electronic Information Countermeasure and Simulation Xidian UniversityXi’an710071China Science and Technology on Communication Information Security Control Laboratory Jiaxing314033China

This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open *** spatial distribution feature extraction layer in SDFEN replaces convolutional output neural networks with the spatial distribution features that focus more on inter-sample information by incorporating class center *** designed hybrid loss function considers both intra-class distance and inter-class distance,thereby enhancing the similarity among samples of the same class and increasing the dissimilarity between samples of different classes during ***,this method allows unknown classes to occupy a larger space in the feature *** reduces the possibility of overlap with known class samples and makes the boundaries between known and unknown samples more ***,the feature comparator threshold can be used to reject unknown *** signal open set recognition,seven methods,including the proposed method,are applied to two kinds of electromagnetic signal data:modulation signal and real-world *** experimental results demonstrate that the proposed method outperforms the other six methods overall in a simulated open ***,compared to the state-of-the-art Openmax method,the novel method achieves up to 8.87%and 5.25%higher micro-F-measures,respectively.

关键词： Electromagnetic signal recognition deep learning feature extraction open set recognition

Predicting the International Roughness Index of JPCP and CRCP Rigid Pavement:A Random Forest(RF)Model Hybridized with Modified Beetle Antennae Search(MBAS)for Higher Accuracy

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1557-1582页

作者： zhou Ji Mengmeng zhou Qiang Wang Jiandong Huang College of Civil and Environmental Engineering Hunan University of Science and EngineeringYongzhou425006China School of Mines China University of Mining and TechnologyXuzhou221116China School of Civil Engineering Guangzhou UniversityGuangzhou510006China

To improve the prediction accuracy of the International Roughness Index(IRI)of Jointed PlainConcrete Pavements(JPCP)and Continuously Reinforced Concrete Pavements(CRCP),a machine learning approach is developed in this study for the modelling,combining an improved Beetle Antennae Search(MBAS)algorithm and Random Forest(RF)*** 10-fold cross-validation was applied to verify the reliability and accuracy of the model proposed in this *** importance scores of all input variables on the IRI of JPCP and CRCP were analysed as *** results by the comparative analysis showed the prediction accuracy of the IRI of the newly developed MBAS and RF hybrid machine learning model(RF-MBAS)in this study is higher,indicated by the RMSE and R values of 0.2732 and 0.9476 for the JPCP as well as the RMSE and R values of 0.1863 and 0.9182 for the *** accuracy of this obtained result far exceeds that of the IRI prediction model used in the traditional Mechanistic-Empirical Pavement Design Guide(MEPDG),indicating the great potential of this developed *** importance analysis showed that the IRI of JPCP and CRCP was proportional to the corresponding input variables in this study,including the total joint faulting cumulated per KM(TFAULT),percent subgrade material passing the 0.075-mm Sieve(P_(200))and pavement surface area with flexible and rigid patching(all Severities)(PATCH)which scored higher.

关键词： Cement pavement JPCP CRCP RF-MBAS IRI

Hot Compression Behavior and Tensile Property of a Novel Ni-Co-Based Superalloy Prepared by Electron Beam Smelting Layered Solidification Technology

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 283-292页

作者： Yong-Chao Gai Rui Zhang Chuan-Yong Cui Zi-Jian zhou Yi Tan Yi-zhou zhou Xiao-Feng Sun Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The hot compression behavior and tensile strength after compression of a new Ni-Co-based superalloy produced using electron beam smelting layered(EBSL)solidification technology were *** compression tests were performed at temperatures of 1120℃and 1150℃,with strain rates of 1 s^(-1) and 0.01 s^(-1),reaching a true strain of *** strength was evaluated at room *** results revealed that this EBSL technology accelerates dynamic recrystallization(DRX),without compromising the strength of alloy.A significant correlation between the volume fraction of DRX and the strain rate was observed,with higher fractions at lower strain rates,leading to higher tensile ***,at the same strain rate,the specimens compressed at 1120℃exhibited higher tensile strength due to undissolvedγ′*** solution and aging heat treatment,the alloy maintained high tensile *** results suggested that the EBSL Ni-Co-based superalloy offers excellent prospects for practical applications.

关键词： Ni-Co-based superalloy Hot deformation Electron beam smelting Tensile strength

An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices

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Nano-Micro Letters 2024年第5期16卷 352-369页

作者： Wenchao Zhao Haifeng zhou Wenkang Li Manlin Chen Min zhou Long Zhao State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic ***,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft *** resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)*** well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and ***,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic *** highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output *** particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental *** study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications.

关键词： Ionic liquids Double-network hydrogels Temperature tolerance Multifunctionality Flexible electronic devices