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Self-trapping under two-dimensional spin-orbit coupling and spatially growing repulsive nonlinearity

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Frontiers of physics 2018年第4期13卷 259-274页

作者： Rong-Xuan Zhong zhao-pin chen Chun-Qing Huang Zhi-Huan Luo Hai-Shu Tan Boris A. Malomed Yong-Yao Li School of Physics and Optoelectronic Engineering Foshan University Foshan 528000 China Department of Physical Electronics School of Electrical Engineering Faculty of Engineering Tel Aviv University Tel Aviv 69978 Israel College of Electronic Engineering South China Agricultural University Guangzhou 510642 China ITMO University St. Petersburg 197101 Russia

We develop a method for creating two- and one-dimensional （2D and 1D） self-trapped modes in bi- nary spin-orbit-coupled Bose-Einstein condensates with the contact repulsive interaction, whose local strength grows sufficiently rapidly from the center to the periphery. In particular, an exact semi-vortex （SV） solution is found for the anti-Gaussian radial modulation profile. The exact modes are included in the numerically produced family of SV solitons. Other families, in the form of mixed modes （MMs）, as well as excited states of SVs and MMs, are also produced. Although the excited states are unstable in all previously studied models, they are partially stable in the present one. In the 1D version of the system, exact solutions for the counterpart of SVs, namely, semi-dipole solitons, are also found. Families of semi-dipoles, as well as the 1D version of MMs, are produced numerically.

关键词： spin-orbit coupling semi-vortex mixed mode excited states

Utilizing BP neural networks to accurately reconstruct the tritium depth profile in materials for BIXS

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Nuclear Science and Techniques 2025年第1期36卷 103-114页

作者： chen zhao Wei Jin Yan Shi Chang-An chen Yi-Ying zhao Institute of Materials China Academy of Engineering PhysicsJiangyou 621908China

β-ray-induced X-ray spectroscopy(BIXS)is a promising method for tritium detection in solid materials because of its unique advantages,such as large detection depth,nondestructive testing capabilities,and low requirements for sample ***,high-accuracy reconstruction of the tritium depth profile remains a significant challenge for this *** this study,a novel reconstruction method based on a backpropagation(BP)neural network algorithm that demonstrates high accuracy,broad applicability,and robust noise resistance is *** average reconstruction error calculated using the BP network(8.0%)was much lower than that obtained using traditional numerical methods(26.5%).In addition,the BP method can accurately reconstruct BIX spectra of samples with an unknown range of tritium and exhibits wide applicability to spectra with various tritium ***,the BP network demonstrates superior accuracy and stability compared to numerical methods when reconstructing the spectra,with a relative uncertainty ranging from 0 to 10%.This study highlights the advantages of BP networks in accurately reconstructing the tritium depth profile from BIXS and promotes their further application in tritium detection.

关键词： β-ray-induced X-ray spectroscopy Tritium detection BP network Ridge regression Reconstruction problem

Significant changes in the physicochemical properties of BC-containing particles during the cold season in Beijing

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Journal of Environmental Sciences 2025年第5期151卷 667-676页

作者： Shuya Hu Linghan Zeng Gang zhao Shiyi chen Chunsheng zhao Weilun zhao Min Hu State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Research Center for Atmospheric Research(IJRC)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and TechnologyNanjing 210044China

The ambient air quality has improved significantly under strict emission controls in Beijing,China over the last *** carbon(BC),as a short-lived climate forcer in ambient aerosols,profoundly impacts the air quality and *** studies have demonstrated a decline in the mass concentration of *** this study,we characterized the chemical compositions and size distributions of BC-containing particles during the cold season of 2022 in Beijing using state-of-the-art instruments capable of exclusively measuring BCcontaining *** optical properties of BC-containing particles were further calculated based on the Mie ***,we compared the properties of BC-containing particles in 2022 with the results of previous *** results showed that the diameters of BC cores became larger while the coating thickness of BC-containing particles became thinner in *** the coating materials,the mass fraction of nitrate increased obviously,and even replaced organic matter as the dominant component during the peak of the pollution *** in chemical compositions and size distributions resulted in lower mass absorption cross-sections(MAC)of BC-containing particles from 10.5±1.1 m^(2)/g in 2016 to 7.3±0.8 m^(2)/g in 2022,reduced by 30.5%.Our results demonstrate the synergistic benefits of air pollution control in improving air quality and mitigating climate ***,the MAC of BC adopted in climate models should vary with the changing air pollution *** study emphasizes that it is imperative to conduct long-term observations of BC-containing particles to better estimate BC’s climate effects.

关键词： Black carbon Chemical composition Size distribution Light absorption ability

A non-fluorinated liquid-like membrane with excellent anti-scaling performance for membrane distillation

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Chinese Chemical Letters 2025年第1期36卷 521-528页

作者： Jianwen zhao Shuai Wang Shanshan zhao Liwei chen Fangang Meng Xuelin Tian State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China Key Laboratory for Polymeric Composite&Functional Materials of Ministry of Education Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable DevicesSun Yat-sen UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510006China

Membrane distillation(MD)has gained extensive attention for treating highly saline ***,membrane scaling during the MD process has hindered the rapid development of this *** approaches to mitigate scaling in membrane distillation focus primarily on achieving enhanced hydrophobicity and even superhydrophobicity via utilizing fluorinated fibrous membrane or introducing perfluorosilane *** the environmental hazards posed by fluorinated compounds,it is highly desirable to develop non-fluorinated membranes with enhanced anti-scaling properties for effective membrane *** this study,we present a non-fluorinated liquid-like MD membrane with exceptional anti-scaling *** membrane was facilely fabricated by grafting linear polydimethylsiloxane(LPDMS)onto a hydrophilic polyether sulfone(PES)membrane pre-coated with the intermediate layers of polydopamine and silica(denoted as LPDMS-PES).Remarkably,LPDMS-PES manifested a drastically improved scaling resistance in continuous MD tests than its perfluorinated counterpart,i.e.,1H,1H,2H,2H-perfluorooctyltrichlorosilane-modified PES membrane(PFOS-PES),in both heterogeneous nucleation-dominated and crystal deposition-dominated scaling processes,despite the latter having a smaller surface ***-PES demonstrated a reduction of crystal accumulation of approximately 85%for Na Cl and 73%for Ca SO_(4) in the heterogeneous nucleation-dominated scaling process compared to ***,in the crystal deposition-dominated scaling process LPDMS-PES exhibited a reduction of about 70%in scale *** results explicitly evidenced the great potential of the liquid-like membrane to minimize scaling in membrane distillation by inhibiting both scale nucleation and adhesion onto the *** believe the findings of this study have important implications for the design of high-performance MD membranes,particularly in the quest for environmentally susta

关键词： Surface modification Liquid-like membranes Anti-scaling Non-fluorinated Direct contact membrane distillation

Design and preparation of a sintered Nd-Y-Fe-B magnet with high magnetic properties via multi-main-phase process and subsequent grain boundary diffusion

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Journal of Rare Earths 2025年第2期43卷 304-311页

作者： Fugang chen Suxin Lu Jie Wang Yong zhao Wenqiang zhao Zhi Xu School of Materials Science and Engineering Jiangsu University of Science and Technology Baotou Tianshi Rare Earth New Materials Co. Ltd. Jiangsu Yangzi Xinfu Shipbuilding Co. Ltd.

A sintered Nd-Y-Fe-B magnet was designed and manufactured by the multi-main-phase *** distributed Y in the magnet decreases the adverse magnetic weakening effect of Y on the *** boundary diffusion process（GBDP） was conducted to further enhance the coercivity of the Nd-Y-Fe-B *** coercivity increases significantly from 884 to 1741 kA/m after GBDP with *** mechanism of the coercivity enhancement is discussed based on the microstructure *** simulation reveals that when the diffused Tb-rich shell thickness is lower than 12 nm the c-plane shell（perpendicular to the c-axis） is much more effective in enhancing the coercivity than the side plane shell（parallel to the c-axis）.But when the Tb-rich shell thickness is above12 nm the side plane shell contributes more to the coercivity *** results in this work can help to design and manufacture Nd-Fe-B magnets with low cost and high magnetic properties.

关键词： Grain boundary diffusion Micromagnetic simulation Multi-main-phase process Nd-Fe-B magnets Rare earths

Machine learning for online control of particle accelerators

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 94-104页

作者： Xiaolong chen Zhijun Wang Yuan He Hong zhao Chunguang Su Shuhui Liu Weilong chen Xiaoying zhao Xin Qi Kunxiang Sun Chao Jin Yimeng Chu Hongwei zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Advanced Energy Science and Technonlogy Guangdong Laboratory Huizhou 516000China Department of Physics Xiamen UniversityXiamen 361005China

Particle accelerators play a critical role in modern scientific ***,existing manual beam control methods heavily rely on experienced operators,leading to significant time consumption and potential challenges in managing next-generation accelerators characterized by higher beam current and stronger nonlinear *** this paper,we establish a dynamical foundation for designing the online adaptive controller of accelerators using machine *** provides a guarantee for dynamic controllability for a class of scientific instruments whose dynamics are described by spatial-temporal equations of motion but only part variables along the instruments under steady states are *** necessity of using historical time series of beam diagnostic data is *** strategies involve also employing a well-established virtual beamline of accelerators,by which various beam calibration scenarios that actual accelerators may encounter are *** the reinforcement learning algorithm is adopted to train the controller with the interaction to the virtual ***,the controller is seamlessly transitioned to real ion accelerators,enabling efficient online adaptive control and ***,the controller demonstrates significant robustness,effectively managing beams with diverse charge mass ratios without requiring *** a controller allows us to achieve the global control within the entire superconducting section of the China Accelerator Facility for Superheavy Elements.

关键词： nonlinear complex system adaptive control machine learning particle accelerator simulation to reality

Exit options sustain altruistic punishment and decrease the second-order free-riders, but it is not a panacea

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Science China(Information Sciences) 2025年第1期68卷 278-291页

作者： chen SHEN zhao SONG Lei SHI Jun TANIMOTO Zhen WANG Faculty of Engineering Sciences Kyushu University School of Statistics and Mathematics Yunnan University of Finance and Economics School of Computing Engineering and Digital Technologies Teesside University School of Artificial Intelligence OPtics and Electro Nics (iOPEN) Northwestern Polytechnical University

Why do humans punish free riders at their own expense? This behavior represents an evolutionary puzzle in human societies. This study explores the role of exit strategies in fostering altruistic punishment within evolutionary game theory. We extend the traditional prisoner's dilemma model by incorporating exiters, players who opt out for a small payoff while nullifying their opponent's payoff, and altruistic punishers who cooperate and punish non-cooperators. Our findings indicate that in well-mixed populations, exiters destabilize defection but do not promote altruistic punishment. In social networks, however,exiters enable altruistic punishment via cyclic dominance among altruistic punishers, defectors, and exiters. Notably, this cyclic dominance is sensitive to exit payoffs; adjustments can lead to cyclic dominance of non-punishing cooperators, defectors, and exiters, or to a bi-stable state between these two types of cyclic dominance. These results highlight the nuanced impact of exiters on altruistic punishment, emphasizing the need for careful incentivization of exit behavior. While exiters can support altruistic punishment in networked populations, their effectiveness is not a panacea and is highly sensitive to exit payoffs, indicating limits to the voluntary participation mechanism.

关键词： evolutionary game theory altruistic punishment coexistence cyclic dominance bi-stable

Unraveling the reaction mechanism of high reversible capacity CuP_(2)/C anode with native oxidation PO_(x) component for sodium-ion batteries

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Chinese Chemical Letters 2025年第1期36卷 574-578页

作者： Huixin chen chen zhao Hongjun Yue Guiming Zhong Xiang Han Liang Yin Ding chen State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China CAS key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesNanjing Forestry UniversityNanjing 210037China Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Institute of Physics Chinese Academy of SciencesBeijing 100190China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi institutesChinese Academy of SciencesXiamen 361021China

Phosphorus-based anode is a promising anode for sodium-ion batteries(SIBs)due to its high specific capacity,however,suffers from poor electronic conductivity and unfavorable electrochemical *** metals such as copper(Cu)into phosphorus has been demonstrated to not only improve the electronic conductivity but also accommodate the volume change during cycling,yet the underline sodiation mechanism is not ***,take a copper phosphide and reduced graphene oxide(CuP_(2)/C)composite as an example,which delivers a high reversible capacity of>900 mAh/***,it is revealed that the native oxidation PO_(x)components of the CuP_(2)/C composite show higher electrochemical reversibility than the bulk Cu P_(2),based on a quantitative analysis of high-resolution solid-state^(31)P NMR,ex-situ XPS and synchrotron X-ray diffraction characterization *** sodiation products Na_(3)PO_(4) and Na_(4)P_(2)O_(7) derived from PO_(x) could react with Na-P alloys and regenerate to PO_(x) during charge process,which probably accounts for the high reversible capacity of the Cu P_(2)/C *** findings also illustrate that the phosphorus transforms into nanocrystalline Na_(3)P and Na_(x)P alloys,which laterally shows crystallization-amorphization evolution process during cycling.

关键词： CuP_(2)/C composite POx component Reaction mechanism Solid-state NMR Sodium-ion batteries

Carbon emissions in China’s steel industry from a life cycle perspective:Carbon footprint insights

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Journal of Environmental Sciences 2025年第2期148卷 650-664页

作者： Xiaocong Song Shuai Du chenning Deng Peng Shen Minghui Xie Ci zhao chen chen Xiaoyu Liu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Beijing Key Laboratory of Water Resources&Environmental Engineering China University of Geosciences(Beijing)Beijing 100083China Chinese Research Academy of Environmental Sciences Environmental Technology&Engineering Co.Ltd. Beijing 100012China

China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in ***,research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development *** constructed a carbon dioxide(CO_(2))emission model for China’s iron and steel industry froma life cycle perspective,conducted an empirical analysis based on data from2019,and calculated the CO_(2)emissions of the industry throughout its life *** emission reduction factors were identified using sensitivity *** results demonstrated that the CO_(2)emission intensity of the steel industry was 2.33 ton CO_(2)/ton,and the production and manufacturing stages were the main sources of CO_(2)emissions,accounting for 89.84%of the total steel life-cycle ***,fossil fuel combustion had the highest sensitivity to steel CO_(2)emissions,with a sensitivity coefficient of 0.68,reducing the amount of fossil fuel combustion by 20%and carbon emissions by 13.60%.The sensitivities of power structure optimization and scrap consumption were similar,while that of the transportation structure adjustment was the lowest,with a sensitivity coefficient of less than *** the current strategic goals of peak carbon and carbon neutrality,it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies,increase the ratio of scrap steel to steelmaking,and build a new power system.

关键词： Iron and steel industry Life cycle Carbon dioxide(CO_(2))emissions Carbon footprint China