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Establishing the vector-meson-exchange dominance for the short range interactions of light quarks

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Science China(physics,Mechanics & Astronomy) 2025年第3期68卷 190-191页

作者： Bing-Song Zou Department of physics Tsinghua UniversityBeijing100084China CAS Key Laboratory of Theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing100190China School of physics University of Chinese Academy of SciencesBeijing100049China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou516000China

Understanding the interactions between constituent quarks is one of the fundamental and challenging problems in hadron *** present,the constituent quark models have achieved great success in describing the properties of hadrons,whereas some long-standing disputes remain,especially for the short range interactions between constituent *** exploring the dynamic mechanism between u/d quarks,it is found that the one gluon exchange and/or vector meson exchange induced interactions may dominate the short range interactions[1].

关键词： quark exchange meson

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Bulk photovoltaic effect in two-dimensional ferroelectric α-In2Se3

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Science China(Information sciences) 2025年第2期68卷 285-292页

作者： Huiting WANG Shuaiqin WU Yan CHEN Qianru ZHAO Jinhua ZENG Ruotong YIN Yuqing ZHENG Chang LIU Shukui ZHANG Tie LIN Hong SHEN Xiangjian MENG Jun GE Xudong WANG Junhao CHU Jianlu WANG State Key Laboratory of Infrared physics Shanghai Institute of Technical PhysicsChinese Academy of Sciences University of Chinese academy of sciences Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception Institute of OptoelectronicsFudan University Hangzhou institute for Advanced Study University of Chinese Academy of Sciences Frontier institute of Chip and System Fudan University

Non-centrosymmetric material systems can generate spontaneous photocurrent without a p-n junction under uniform illumination, which is known as the bulk photovoltaic effect（BPVE）. It has garnered significant attention for its application potential in the fields of energy harvesting and photoelectric detection. In this study, we report the BPVE observed in twodimensional ferroelectric α-In2Se3multilayer flakes. The reversal in spontaneous photocurrent polarity is observed and associated with the out-of-plane ferroelectric polarization direction. The spontaneous photocurrent originating from the shift current is also polarization-sensitive. The amplitude of spontaneous photocurrent is further increased by one order of magnitude through vacuum annealing. Our results provide a further application potential for new-generation photodetectors based on BPVE with low power consumption and multi-dimensional optoelectronic detection.

关键词： bulk photovoltaic effect 2D ferroelectrics 3R $\alpha$-In$_2$Se$_3$ shift current self-powered photodetection

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Constraints on holographic QCD phase transitions from PTA observations

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Science China(physics,Mechanics & Astronomy) 2025年第1期68卷 67-74页

作者： Song He Li Li Sai Wang Shao-Jiang Wang Center for Theoretical physics and College of physics Jilin UniversityChangchun 130012China School of Physical Science and Technology Ningbo UniversityNingbo 315211China CAS Key Laboratory of Theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental physics and Mathematical sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences(UCAS)Hangzhou 310024China Theoretical physics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Max Planck institute for Gravitational physics(Albert Einstein institute) Am Muhlenberg 1Golm 14476Germany

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition,yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT)left *** specific baryon chemical poten-tial,the first-order QCD phase transition agrees with the observational constraint of baryon ***,therefore,provides a scenario for phase transition gravitational waves(GWs)within the standard model of particle *** these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA)observations,the duration of this FoPT can be well constrained,and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu Wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese academy of sciences Beijing 100049China

The methanol-to-olefins(MTO)reaction offers an alternative pathway for the production of low-carbon olefins from non-oil *** research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in ***-situ solid-state nuclear magnetic resonance(ss NMR)spectroscopy has emerged as a pivotal tool,offering crucial insights into key species under real-time operando ***,the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ^(13)C MAS NMR and 2D correlation ***,recent technological advancements in hyperpolarization(HP)methods,including HP^(129)Xe NMR and dynamic nuclear polarization(DNP),have significantly improved the sensitivity of ssNMR,enabling detailed structural and kinetic analysis as well as the detection of trace *** this feature article,we summarized recent advancements in(in-situ)ssNMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest *** theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts,thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

Long-duration aqueous Zn-ion batteries achieved by dual-salt highly-concentrated electrolyte with low water activity

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Journal of Energy Chemistry 2025年第2期101卷 778-785页

作者： Lvzhang Jiang Lingbo Yao Gege Wang Chang Liu Xiaowei Chi Yu Liu Shanghai institute of Ceramics Chinese Academy of Sciences University of Chinese academy of sciences

Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost ***,their practical applications are at a slow pace due to their short cycle life,which fundamentally results from the instability of the positive/negative electrode interface in the traditional dilute aqueous electrolytes with high water *** highly concentrated electrolyte（HCE）has been considered as an effective *** previous studies of single salt-based HCE（SSHCE）,herein,a new dual-salt HCE（15 m ZnCl2+10 m NH4NH2SO3DS-HCE） was proposed for the first ***-HCE was proven to simultaneously possess higher conductivity than traditional dilute electrolytes and ultralow water activity of SS-HCE by the regulation of dual high-concentration salts on the solvation structure,which renders the Zn‖Zn symmetric cell the record-long cycling life of 2200 h compared with those with SS-HCE（30 m ZnCl2,300 h） and other reported ***,the Zn‖NH4V4O10full cell with DS-HCE demonstrated impressed rate capability within a wide-range current densities from 0.1 to 10 A ***,at the high current density of 5 A g-1,the full cell shows almost100% capacity retention after 4000 cycles,which indicates the promising future of the DS-HCE system for long-duration aqueous Zn-ion batteries.

关键词： Ammonium vanadate Aqueous zinc battery Cycling stability Electrolyte

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(physics,Mechanics & Astronomy) 2025年第1期68卷 93-104页

作者： Pan Guo Hong-Bo Jin Cong-Feng Qiao Yue-Liang Wu The International Centre for Theoretical physics Asia-Pacific University of Chinese Academy of SciencesBeijing 100190China institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China The School of Physical sciences University of Chinese Academy of SciencesBeijing 100049China institute of Theoretical physics Chinese Academy of SciencesBeijing 100190China

For space-based gravitational wave(GW)detection,the main noise source for massive black hole binaries(MBHBs)is attributed to approximately 107 double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratioΔD_(L)/D_(L) at the 95%confidence level,is enhanced by factors of∼*** angular resolutions,denoted byΔΩs,are enhanced by a factor of∼*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

A monolithic 3D IGZO-RRAM-SRAM-integrated architecture for robust and efficient compute-in-memory enabling equivalent-ideal device metrics

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Science China(Information sciences) 2025年第2期68卷 322-337页

作者： Shengzhe YAN Zhaori CONG Zi WANG Zhuoyu DAI Zeyu GUO Zhihang QIAN Xufan LI Xu ZHENG Chuanke CHEN Nianduan LU Chunmeng DOU Guanhua YANG Xiaoxin XU Di GENG Jinshan YUE Lingfei WANG Ling LI Ming LIU institute of Microelectronics of the Chinese academy of sciences University of Chinese academy of sciences

Compute-in-memory(CIM) based on various devices such as static random access memory(SRAM) and resistive random access memory(RRAM) and other emerging devices such as indium-gallium-zinc-oxide(IGZO) transistor, magnetoresistive RAM(MRAM), and ferroelectric RAM(FeRAM) has been explored for better performance and energy efficiency on neural networks applications. However, CIM based on a single-type device suffers a variety of non-ideal metrics to reach the simultaneous optimal accuracy, density, and energy efficiency. This work presents equivalent-ideal CIM(Eq-CIM), a monolithic 3D(M3D) IGZO-RRAM-SRAM integrated architecture for robust and efficient compute-in-memory enabling equivalent-ideal device metrics. To overcome the non-ideality(variation, endurance, temperature, etc.) of the single-type devices, system-technology co-optimization(STCO) is performed. This work highlights the non-ideality-aware functionality breakdown for robust high accuracy and simultaneous high density/efficiency, by utilizing 2T0C IGZO for temporal activation storage, RRAM for high-density weight storage, and SRAM for accurate CIM. Device-to-algorithm variation transfer is applied to analyze the system-level accuracy. We benchmark Eq-CIM architecture on CIFAR-10/ImageNet, with 5.06× storage density and 5.05×/2.45× area/energy efficiency compared with single-type-device-based CIM, and high robustness(<0.27% accuracy loss) from-40℃ to 120℃.

关键词： compute-in-memory (CIM) monolithic 3D RRAM IGZO 3D-stack simulation

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A special core-shell material(Mxene@Ag@Phytate)to improve EVA composite fire safety,radiation cross-linking effect,and electromagnetic shielding

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Nuclear Science and Techniques 2025年第2期36卷 27-39页

作者： Si-Yi Xu Dan-Yi Li Wen-Rui Wang Lin Lin Ying Sun Ji-Hao Li Lin-Fan Li Shanghai institute of Applied physics Chinese Academy of SciencesShanghai 201800China University of Chinese academy of sciences Beijing 100049China

High-performance MXene-based polymer nanocomposites are well-suited for various industrial applications owing to their excellent mechanical,thermal,and other ***,the fabrication of flame-retardant polymer/MXene nanocom-posites remains challenging owing to the limited flame-retardant properties of MXene *** study prepared a novel MXene@Ag@PA hybrid material via radiation modification and complexation *** material was used to further enhance the key properties of ethylene-vinyl acetate(EVA),such as its mechanical properties,thermal conductivity,flame retardancy,and electromagnetic *** addition of two parts of this hybrid material increased the thermal conduc-tivity of EVA by 44.2%and reduced its peak exothermic rate during combustion by 30.1%compared with pure *** material also significantly reduced smoke production and increased the residue *** the X-band,the electromagnetic shielding effectiveness of the EVA composites reached 20 ***,the MXene@Ag@PA hybrid material could be used to further enhance the mechanical properties of EVA composites under electron-beam ***,this study contributes to the development of MXene-based EVA advanced materials that are fire-safe,have high strength,and exhibit good electromagnetic shielding performance for various applications.

关键词： MXene@Ag@PA Ethylene-vinyl acetate(EVA) Flame retardancy Electromagnetic shielding performance

Interpreting hourly mass concentrations of PM_(2.5)chemical components with an optimal deep-learning model

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Journal of Environmental sciences 2025年第5期151卷 125-139页

作者： Hongyi Li Ting Yang Yiming Du Yining Tan Zifa Wang State Key Laboratory of Atmospheric Boundary Layer physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese academy of sciences Beijing 100049China Shenyang Environmental Monitoring Center Shenyang 110167China

PM_(2.5)constitutes a complex and diversemixture that significantly impacts the environment,human health,and climate ***,existing observation and numerical simulation techniques have limitations,such as a lack of data,high acquisition costs,andmultiple *** limitations hinder the acquisition of comprehensive information on PM_(2.5)chemical composition and effectively implement refined air pollution protection and control *** this study,we developed an optimal deep learning model to acquire hourly mass concentrations of key PM_(2.5)chemical components without complex chemical *** model was trained using a randomly partitioned multivariate dataset arranged in chronological order,including atmospheric state indicators,which previous studies did not *** results showed that the correlation coefficients of key chemical components were no less than 0.96,and the root mean square errors ranged from 0.20 to 2.11μg/m^(3)for the entire process(training and testing combined).The model accurately captured the temporal characteristics of key chemical components,outperforming typical machine-learning models,previous studies,and global reanalysis datasets(such asModern-Era Retrospective analysis for Research and Applications,Version 2(MERRA-2)and Copernicus Atmosphere Monitoring Service ReAnalysis(CAMSRA)).We also quantified the feature importance using the random forest model,which showed that PM_(2.5),PM_(1),visibility,and temperature were the most influential variables for key chemical *** conclusion,this study presents a practical approach to accurately obtain chemical composition information that can contribute to filling missing data,improved air pollution monitoring and source *** approach has the potential to enhance air pollution control strategies and promote public health and environmental sustainability.

关键词： Pm2.5 chemical composition Hourly mass concentration Deep learning Bayesian optimization Feature importance