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The breaking of spin sy.metry.in the single-particle resonances in deformed nuclei

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Nuclear Science and Techniques 2024年第3期35卷 237-245页

作者： zhen-y. zheng Shou-Wan Chen Quan Liu School of Phy.ics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The exploration of spin sy.metry.(SS) in nuclear phy.ics has been instrumental in identify.ng atomic nucleus *** this study.we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum *** investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative *** was the initial discovery.of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum *** increasing single-particle energy.the splitting of the resonant spin doublets widened *** escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy.levels *** also analy.ed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay.times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant *** the radial density.of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant *** impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy.and width splitting in the resonant spin doublets,which is attributed to increased component ***,the sensitivity.of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in *** study.provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay.with the nuclear structure,thereby.advancing our understanding of SS in the resonance state.

关键词： Spin sy.metry Resonant states Deformed nuclei Complex-momentum representation

Stability.and accuracy.of central difference method for real-time dy.amic substructure testing considering mass participation coefficient

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 625-636页

作者： zheng Lichang Xu Guoshan y.ng Ge Wang zhen y.ng Kaibo zheng zheny.n School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key.Lab of Structures Dy.amic Behavior and Control Ministry of EducationHarbin Institute of TechnologyHarbin 150090China Key.Lab of Intelligent Disaster Mitigation Ministry of Industry and Information TechnologyHarbin 150090China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China

For real-time dy.amic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability.and accuracy.of the integration algorithms has never been ***,this study.proposes to investigate the stability.and accuracy.of the central difference method(CDM)for RTDST considering the specimen mass participation ***,the theory.of the CDM for RTDST is ***,the stability.and accuracy.of the CDM for RTDST considering the specimen mass participation coefficient are ***,numerical simulations and experimental tests are conducted for verify.ng the effectiveness of the *** study.indicates that the stability.of the algorithm is affected by.the mass participation coefficient of the specimen,and the stability.limit first increases and then decreases as the mass participation coefficient *** most cases,the mass participation coefficient will increase the stability.limit of the algorithm,but in specific circumstances,the algorithm may.lose its *** stability.and accuracy.of the CDM considering the mass participation coefficient are verified by.numerical simulations and experimental tests on a three-story.frame structure with a tuned liquid damper.

关键词： real-time dy.amic substructure testing central difference method stability mass participation coefficient tuned liquid damper

Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm

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Defence Technology.防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting Zha Hailu y.an zhen zheng He Zhang Ministerial Key.Laboratory.of ZNDy Nanjing University of Science and TechnologyNanjing 210094China Science and Technology.on Electromechanical Dy.amic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly.undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability.of the *** order to address the problem of insufficient filtering capacity.in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy.and anti-interference capability.of the ***,experiments are conducted with vary.ng signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by.more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

Partition-based Network Equivalent Method for Power Sy.tem Subsy.chronous Oscillation Analy.is

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Journal of Modern Power Sy.tems and Clean Energy 2024年第1期12卷 313-320页

作者： Chenxuan Wang Weimin zheng zhen Wang y.ngqing Dan Ping Ju the Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China the College of Energy.and Electrical Engineering Hohai UniverstiyNanjing 211100China

Given large-scale modern power sy.tems with pow er electronic converters,the numerical simulation with subsy. chronous oscillation(SSO)faces great challenges in engineering practice due to sharply.enlarged modeling scale and high com putational *** reduce the modeling scale,network parti tion and equivalent becomes a vital technique in numerical sim *** several methods have been developed for net work equivalent,a generally.accepted rule for network parti tion is still *** paper proposes that the sy.tem can be partitioned into three parts,i.e.,the internal,the middle,and the external subsy.tems,in which the internal subsy.tem consists of all power electronic components,the middle subsy. tem includes those selected AC dy.amic components with de tailed models,and the remaining components and buses consti tute the external *** external subsy.tem is further represented by.an equivalent RLC network determined by.the frequency.dependent network equivalent(FDNE)*** the proposed method,the observability.index and the electrical distance index are used to identify.the interface between the middle and the external *** studies based on a modified Hy.ro-Quebec sy.tem are used to verify.the effective ness of the proposed method.

关键词： Electrical distance network equivalent subsy. chronous oscillation observability.index

Experimental observation of spontaneous sy.metry.breaking in a quantum phase transition

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Science China(Phy.ics,Mechanics & Astronomy. 2024年第2期67卷 34-39页

作者： Wen Ning Ri-Hua zheng Jia-Hao Lu Fan Wu zhen-Biao y.ng Shi-Biao zheng Fujian Key.Laboratory.of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350108China Hefei National Laboratory Hefei 230088China

Spontaneous sy.metry.breaking(SSB)play. a central role in understanding a large variety.of phenomena associated with phase transitions,such as superfluid and *** far,the transition from a sy.metric vacuum to a macroscopically.ordered phase has been substantially.*** process bridging these two distinct phases is critical to understanding how a classical world emerges from a quantum phase transition,but so far remains unexplored in *** here report an experimental demonstration of such a process with a quantum Rabi model engineered with a superconducting *** move the sy.tem from the normal phase to the superradiant phase featuring two sy.metry.breaking field components,one of which is observed to emerge as the classical *** results demonstrate that the environment-induced decoherence play. a critical role in the SSB.

关键词： quantum phase transition Rabi model spontaneous sy.metry.breaking superconducting circuit Schrodinger cat states

A comparative study.on characteristics of retracted publications across different open access levels

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Journal of Data and Information Science 2024年第2期9卷 22-40页

作者： Er-Te zheng Hui-zhen Fu Department of Information Resources Management School of Public AffairsZhejiang UniversityHangzhou 310058China School of Information Resource Management Renmin University of ChinaBeijing 100872China

Purpose:Recently.global science has shown an increasing open trend,however,the characteristics of research integrity.of open access(OA)publications have rarely.been *** aim of this study.is to compare the characteristics of retracted articles across different OA levels and discover whether OA level influences the characteristics of retracted ***/methodology.approach:The research conducted an analy.is of 6,005 retracted publications between 2001 and 2020 from the Web of Science and Retraction Watch *** publications were categorized based on their OA levels,including Gold OA,Green OA,and *** study.explored retraction rates,time lags and reasons within these ***:The findings of this research revealed distinct patterns in retraction rates among different OA *** with Gold OA demonstrated the highest retraction rate,followed by.Green OA and non-OA.A comparison of retraction reasons between Gold OA and non-OA categories indicated similar proportions,while Green OA exhibited a higher proportion due to falsification and manipulation issues,along with a lower occurrence of plagiarism and authorship *** retraction time lag was shortest for Gold OA,followed by.non-OA,and longest for Green *** prolonged retraction time for Green OA could be attributed to an aty.ical distribution of retraction reasons.A comparative study.on characteristics of retracted publications across different open access levels Research limitations:There is no exploration of a wider range of OA levels,such as Hy.rid OA and Bronze *** implications:The outcomes of this study.suggest the need for increased attention to research integrity.within the OA *** occurrences offalsification,manipulation,and ethical concerns within Green OA publications warrant attention from the scientific ***/value:This study.contributes to the understanding of research integrity.in the realm of OA publications,she

关键词： Open access Retracted publications Reasons for retraction Retraction time lag Bibliometrics

Controlling reversible complexation-mediated poly.erization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： Xin Fu zhen Lu Shen Li zheng-Hong Luo Lin-Xi Hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingy.an Innovation Laboratory Quanzhou 362801China

The exploitation of new green poly.erization avenues for the effective sy.thesis of poly.ers by.reversible-deactivation radical poly.erization play. a critical role in pursuing the development of poly.eric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hy.rogen-bonding interaction were constructed as cataly.ts and medium for actuating reversible complexation-mediated poly.erization(RCMP)for the first time,y.elding methacry.ate poly.ers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary.reaction of RCMP were explored deeply.revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hy.rogen-bond was primary.factor to influence poly.erization ***,the insights of density.functional theory.calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other poly.erization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated poly.erization intermolecular hy.rogen bonding density.functional theory elementary.reaction steps

Climatic impacts induced by.winter wheat irrigation over North China simulated by.the nonhy.rostatic RegCM4.7

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Advances in Climate Change Research 2024年第2期15卷 197-210页

作者： Jia WU zhen-y. HAN Xue-Jie GAO zheng-Jia LIU National Climate Centre China Meteorological AdministrationBeijing 100081China Key.Laboratory.for Climate Studies China Meteorological AdministrationBeijing 100081China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Quantification of the impact of winter wheat irrigation on the climate and the occurrence of extreme climatic events over North China is crucial for regional adaptation *** related studies mainly.focused on the impact on surface processes;however,few focused on the effects of extreme events using high-resolution nonhy.rostatic regional climate ***,the 9-km-resolution nonhy.rostatic RegCM4.7 was coupled with a crop irrigation scheme and an updated winter wheat irrigation dataset to better simulate irrigation *** experiments were conducted with and without winter wheat irrigation to isolate the effects of *** showed that irrigation simulation reduces the model biases in temperature,precipitation,latent heat flux,soil moisture,sensitive heat flux,and top-lay.r soil ***,it also reduces the bias and increases the correlation with observations obtained in irrigated areas,especially.in summer,indicating better representation of irrigation *** wheat irrigation tends to cause substantial cooling of the local surface maximum,minimum,and mean air temperatures(by.1.68,-0.34,and-0.79℃,respectively.over irrigated areas of North China,with the largest changes observed in relation to maximum ***,precipitation is found to increase during spring and summer,which is strongly.related to water vapor transport in the lower levels of the *** analy.es indicated that the number of annual mean hot day. decrease(-13.9 d),whereas the number of both comfort day.(+10.2 d)and rainy.day.(day. with total precipitation greater than 1 mm:+6.6 d)increase over irrigated areas,demonstrating beneficial feedback to human perception and ***,although the heat wave risk increases(number of annual mean heat wave day.:+5.8 d),the impact is limited to small areas within irrigated ***,no notable change was found in terms of heavy.rainfall events and precipitation intensity

关键词： Nonhy.rostatic regional climate model Irrigation effect Extreme events North China

Highly.Aligned Graphene Aerogels for Multifunctional Composites

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Nano-Micro Letters 2024年第6期16卷 276-342页

作者： y.ng Wu Chao An y.ru Guo y.ngy.ng Zong Naisheng Jiang Qingbin zheng Zhong‑zhen y. Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhenGuangdong 518172People’s Republic of China State Key.Laboratory.of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Stemming from the unique in-plane honey.omb lattice structure and the sp^(2)hy.ridized carbon atoms bonded by.exceptionally.strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,and thermal *** maximize the utilization of graphene’s in-plane properties,pre-constructed and aligned structures,such as oriented aerogels,films,and fibers,have been *** unique combination of aligned structure,high surface area,excellent electrical conductivity.mechanical stability.thermal conductivity.and porous nature of highly.aligned graphene aerogels allows for tailored and enhanced performance in specific directions,enabling advancements in diverse *** review provides a comprehensive overview of recent advances in highly.aligned graphene aerogels and their *** highlights the fabrication methods of aligned graphene aerogels and the optimization of alignment which can be estimated both qualitatively.and *** oriented scaffolds endow graphene aerogels and their composites with anisotropic properties,showing enhanced electrical,mechanical,and thermal properties along the alignment at the sacrifice of the perpendicular *** review showcases remarkable properties and applications of aligned graphene aerogels and their composites,such as their suitability.for electronics,environmental applications,thermal management,and energy.*** and potential opportunities are proposed to offer new insights into prospects of this material.

关键词： Highly.aligned graphene aerogels Quantitative characterization of alignment Multifunctional composites Anisotropic properties Multifunctional applications