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Strong-field photoelectron holography in the subcycle limit

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Light(Science & Applications) 2024年第6期13卷 1032-1040页

作者： Tsendsuren Khurelbataro Jaewuk Heo ShaoGang Yu XuanYang Lai XiaoJun Liu Dong Eon Kim Center for Attosecond Science and technology Department of PhysicsPohang University of Science and TechnologyPohangGyeongbuk37673Korea Max Planck POSTECH/KOREA research Initiative PohangGyeongbuk37673Korea State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences430071WuhanChina Wuhan Institute of Quantum technology 430206WuhanChina

Strong-field photoelectron holography is promising for the study of electron dynamics and structure in atoms and molecules,with superior spatiotemporal resolution compared to conventional electron and X-ray ***,the application of strong-field photoelectron holography has been hindered by inter-cycle interference from multicycle ***,we address this challenge by employing a near-single-cycle field to suppress the inter-cycle *** observed and separated two distinct holographic patterns for the first *** measurements allow us not only to identify the Gouy phase effect on electron wavepackets and holographic patterns but also to correctly extract the internuclear separation of the target molecule from the holographic *** work leads to a leap jump from theory to application in the field of strong-field photoelectron holography-based ultrafast imaging of molecular structures.

关键词： photoelectron holographic cycle

Atomscopic of ripple origins for two-dimensional monolayer transition metal dichalcogenides

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Nano research 2024年第3期17卷 2136-2144页

作者： Haitao Yu Mingzi Sun Xiao Wu Cheuk Hei Chan Bolong Huang Zhong Lin Wang CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 100083China School of Nanoscience and technology University of Chinese Academy of SciencesBeijing 100049China department of Applied Biology and Chemical technology The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina research Centre for Carbon-Strategic Catalysis The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGeorgia 30332USA

During the development of ultrathin two-dimensional(2D)materials,the appearance of ripples has been widely ***,the formation mechanisms and their influences are still rarely investigated,especially their contributions to the electronic structures and optical *** compensate for the knowledge gap,we have carried out comprehensive theoretical studies on the monolayer WSe_(2) with a series of ripple structures from 0 to 12Åin different lattice *** sensitivity of the formation energy,band structures,electronic structures,and optical properties to the ripple structures have been performed systematically for the first *** formation of ripples in Armchair and zigzag simultaneously are more energetically favorable,leading to more flexible optimizations of the optoelectronic *** improved charge-locking effect and extension of absorption ranges indicate the significant role of ripple *** spontaneous formation of ripples is associated with orbital rearrangements and structural *** leads to the unique charge carrier correlate inversion between W-5d and Se-4p orbitals,resulting in the pinning of the Fermi *** work has supplied significant references to understand ultrathin 2D structures and benefit their future developments and applications in high-performance optoelectronic devices.

关键词： two-dimensional(2D)materials ripples strain effect charge carrier correlation inversion optoelectronic properties

Black radish root extract alleviates sodium valproate-induced liver damage via inhibiting mitochondrial membrane potential collapse and oxidative stress in mice

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Asian Pacific Journal of Tropical Biomedicine 2024年第7期14卷 298-306页

作者： Mohammad Hadi Zarei Sami Akbulut Maryam Zafari Elham Saghaei Zahra Lorigooini Hossein AminiKhoei Somaye Khosravi Elham Bijad Medical Plants research Center Basic Health Sciences InstituteShahrekord University of Medical SciencesShahrekordIran department of Liver Transplant Institute and Biostatistics Inonu University Faculty of Medicine44280MalatyaTurkey Student research Committee Shahrekord University of Medical SciencesShahrekordIran Physiology and Pharmacology department School of MedicineShahrekord University of Medical SciencesShahrekordIran department of Anatomical sciences School of MedicineShahrekord University of Medical SciencesShahrekordIran

Objective:To explore the effect of black radish(Raphanus sativus *** niger)root extract on liver enzymes,oxidative stress,and histopathological alterations in mice with sodium valproate-induced ***:Thirty-two mice were divided into four groups:the control group received drinking water by gavage,the second group was administered with 100 mg/kg of sodium valproate,the third group received 300 mg/kg of black radish root extract,and the fourth group was given both sodium valproate(100 mg/kg)and black radish root extract(300 mg/kg).After 28 days,the mice were euthanized,and serum levels of aspartate aminotransferase(AST),alanine aminotransferase(ALT),and alkaline phosphatase(ALP),along with liver malondialdehyde(MDA),reactive oxygen species(ROS),mitochondrial parameters,tumor necrosis factor-alpha(TNF-α)gene expression,and histopathological changes were ***:Sodium valproate caused hepatic damage in mice,characterized by elevated serum levels of liver enzymes,increased MDA and ROS levels and TNF-αgene expression,as well as histopathological *** black radish root extract significantly alleviated sodium valproate-caused hepatic injury by decreasing the serum levels of ALT and AST,MDA,ROS,TNF-αgene expression,as well as mitochondrial impairment,but did not have a significant effect on sodium valproate-induced histopathological ***:The black radish root extract demonstrates protective effects against sodium valproate-induced liver injury,possibly through mitigating oxidative stress,mitochondrial impairment,and inflammatory mediator expression.

关键词： Black radish Raphanus sativus Sodium valproate Hepatotoxicity Oxidative stress Anti-inflammation

Advances in bio-inspired electrocatalysts for clean energy future

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Nano research 2024年第2期17卷 515-533页

作者： Jing-Wen Duan Mu Min-Rui Gao Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Electrocatalysis can enable efficient energy storage and conversion and thus is an effective way to achieve carbon *** unique structure and function of organisms can offer many ideas for the design of electrocatalysts,which has become one of the most promising research ***,the understanding of the mechanism of bio-inspired electrocatalysis has become clearer,which has promoted the design of bio-inspired catalysts and catalytic *** bio-inspired catalysts(enzyme-like catalysts,layered porous catalysts,superhydrophobic/superhydrophilic surfaces,and so on)have been developed to enable efficient electrocatalytic ***,we discuss the key advances in the field of bio-inspired electrocatalysts progressed in recent ***,the role of bio-inspiration in increasing the intrinsic activity and number of active sites of catalysts is ***,the structure and mechanism of layered porous catalytic systems that mimic biological transport systems are comprehensively ***,the design of three-phase interfaces from micro-nanoscale to atomic scale is highlighted,including the wettability of the electrode surface and the transport system near the *** conclude the review by identifying challenges in bio-inspired electrocatalysts and providing insights into future prospects for the exciting research field.

关键词： bio-inspired electrocatalysts active sites layered porous structure three-phase interface

Insights of carbon reduction practices from Winter Olympics 2022

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Science Bulletin 2024年第13期69卷 2034-2037页

作者： Xiaoyong Liao Shuai Zhong Jie Huang Zhu Liu Ayman Elshkaki You Li Lei Shen Yingli He Li An Yidong Zhu Wenhao Sun Tao Liang Jiaoe Wang Jinwei Dong Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory for Resources Use and Environmental Remediation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of sciences Beijing 100049China department of Earth System Science Tsinghua UniversityBeijing 100084China

Concerns about the carbon emissions of mega-events revolve,mainly due to the impactful demonstration effects they ***,accurate monitoring of these emissions is crucial during such events[1].The Olympic and Paralympic Winter Games Beijing 2022(hereinafter“Winter Olympics 2022”)are recognized as the first Games to pay close attention to a wide range of emissions associated with all stages of the *** of emerging carbon reduction technologies,such as low-carbon materials and technologies,have shown promising effects on efforts to achieve carbon neutrality[2].The impacts of individual measures,such as Olympic infrastructure construction.

关键词： Winter emissions carbon

Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 657-678页

作者： Kazem KAZEMI Soroush MODABBERI Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN School of Geology College of ScienceUniversity of TehranTehranIran research Centre for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China National Key Laboratory of Ecological Security and Resource Utilization in Arid Areas Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China department of Geochemistry and Environmental sciences School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China department of Earth and sciences Faculty of SciencesUniversity of KurdistanSanandajIran department of Science Education Farhangian UniversityTehranIran

The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were *** is suggested that the rocks are metaluminous(A/CNK=1.32-1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical *** host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for *** have relatively low SiO_(2) contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived ***-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492-0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2)of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2)=729 Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid *** T_(DM1)(Nd)and T_(DM2)(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian *** composition indicates a crystallization temperature of~1000℃ and a depth of~9 km.

关键词： enclave magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc

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An efficient and mild recycling of waste melamine formaldehyde foams by alkaline hydrolysis

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Green Energy & Environment 2024年第5期9卷 919-926页

作者： Shaodi Wu Ning Zhang Chizhou Wang Xianglin Hou Jie Zhao Shiyu Jia Jiancheng Zhao Xiaojing Cui Haibo Jin Tiansheng Deng Shanxi Engineering research Center of Biorefinery Institute of Coal ChemistryChinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China department of Chemistry and Chemical Engineering Taiyuan Institute of TechnologyTaiyuanShanxi030008China Beijing Key Laboratory of Fuels Cleaning and Advanced Catalytic Emission Reduction technology/College of New Materials and Chemical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China

Melamine formaldehyde foam(MFF)generates many poisonous chemicals through the traditional recycling methods for organic resin ***,a high MFF degradation ratio of ca.97 wt.%was achieved under the mild conditions(160℃)in a NaOH–H2O system with ammelide and ammeline as the main degradation *** alkaline solvent had an obvious corrosion effect for MFF,as indicated by scanning electron microscopy(SEM).The reaction process and products distribution were studied by Fourier-transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and ^(13)C nuclear magnetic resonance(NMR).Besides,the MFF degradation products that have the similar chemical structures and bonding performances to those of melamine can be directly used as the raw material for synthesis of melamine urea-formaldehyde resins(MUFs).Moreover,the degradation system demonstrated here showed the high degradation efﬁciency after reusing for 7 *** degradation process generated few harmful pollutants and no pre-or post-treatments were required,which proves its feasibility in the safe removal or recovery of waste MFF.

关键词： Melamine formaldehyde foam Degradation Alkaline hydrolysis Recycling

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Building and characterizing a stylus ion-trap system

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Chinese Physics B 2024年第4期33卷 122-127页

作者：崔太豪魏雅琪李冀袁泉戴双晴李沛东周飞张建奇郑驻军陈亮冯芒 State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of the Chinese Academy of sciences Beijing 100049China Laboratory of Quantum Science and Engineering South China University of TechnologyGuangzhou 510641China research Center for Quantum Precision Measurement Guangzhou Institute of Industry TechnologyGuangzhou 511458China department of Physics Zhejiang Normal UniversityJinhua 321004China

Cold trapped ions can be excellent sensors for ultra-precision detection of physical quantities,which strongly depends on the measurement situation at *** stylus ion trap,formed by two concentric cylinders over a ground plane,holds the promise of relatively simple structure and larger solid angle for optical access and fluorescence collection in comparison with the conventional ion *** we report our fabrication and characterization of the first stylus ion trap constructed in China,aiming for studying quantum optics and sensing weak electric fields in the *** have observed the stable confinement of the ion in the trapping potential for more than two hours and measured the heating rate of the trap to be dε/dt=7.10±0.13 meV/s by the Doppler recooling *** work starts a way to building practical quantum sensors with high efficiency of optical collection and with ultimate goal for contributing to future quantum information technology.

关键词： stylus ion trap electric-field noises Doppler recooling method heating rate

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Understanding adversarial attacks on observations in deep reinforcement learning

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Science China(Information sciences) 2024年第5期67卷 69-83页

作者： You QIAOBEN Chengyang YING Xinning ZHOU Hang SU Jun ZHU Bo ZHANG department of Computer Science and technology Beijing National Research Center for Information Science and Technology Tsinghua-Bosch Joint Center for Machine Learning Institute for Artificial Intelligence Tsinghua University Peng Cheng Laboratory

Deep reinforcement learning models are vulnerable to adversarial attacks that can decrease the cumulative expected reward of a victim by manipulating its observations. Despite the efficiency of previous optimization-based methods for generating adversarial noise in supervised learning, such methods might not achieve the lowest cumulative reward since they do not generally explore the environmental ***, a framework is provided to better understand the existing methods by reformulating the problem of adversarial attacks on reinforcement learning in the function space. The reformulation approach adopted herein generates an optimal adversary in the function space of targeted attacks, repelling them via a generic two-stage framework. In the first stage, a deceptive policy is trained by hacking the environment and discovering a set of trajectories routing to the lowest reward or the worst-case performance. Next, the adversary misleads the victim to imitate the deceptive policy by perturbing the observations. Compared to existing approaches, it is theoretically shown that our adversary is strong under an appropriate noise level. Extensive experiments demonstrate the superiority of the proposed method in terms of efficiency and effectiveness, achieving state-of-the-art performance in both Atari and MuJoCo environments.

关键词： deep learning reinforcement learning adversarial robustness adversarial attack