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Chinese physics B 2024年第7期33卷 448-454页

作者：潘小龙王豪柳雷陈向荣耿华运 College of physics Sichuan UniversityChengdu 610065China national key laboratory of shock Wave and detonation physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China

Mn_(3)TeO_(6)(MTO) has been experimentally found to adopt a P2_(1)/In structure under high pressure,which exhibits a significantly smaller band gap compared to the atmospheric R3 *** this study,we systematically investigate the magnetism,structural phase transition,and electronic properties of MTO under high pressure through first-principles *** R3 and P2_(1)/n phases of MTO are antiferromagnetic at zero *** R3 phase transforms to the P2_(1)/n phase at 7.5 8 GPa,accompanied by a considerable volume collapse of about 6.47%.Employing the accurate method that combines DFT+U/and GW,the calculated band gap of R3 phase at zero pressure is very close to the experimental values,while that of the P2_(1)/n phase is significantly *** main reason for this difference is that the experimental study incorrectly used the Kubelka-Munk plot for the indirect band gap to obtain the band gap of the P2_(1)/n phase instead of the Kubelka-Munk plot for the direct band ***,our study reveals that the transition from the R3 phase to the P2_(1)/n phase is accompanied by a slight reduction in the band gap.

关键词： magnetism phase transition band gap high pressure

A comprehensive diagnostic system of ultra-thin liquid sheet targets

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High Power Laser Science and Engineering 2024年第3期12卷 41-50页

作者： Ziyang Peng Zhengxuan Cao Xuan Liu Yinren Shou Jiarui Zhao Shiyou Chen Ying Gao Pengjie Wang Zhusong Mei Zhuo Pan Defeng Kong Shirui Xu Zhipeng Liu Yulan Liang Tianqi Xu Tan Song Xun Chen Qingfan Wu Yujia Zhang Zihao Zhang Xueqin Yan Wenjun Ma State key laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijingChina national key laboratory of shock Wave and detonation physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyangChina Center for Relativistic Laser Science Institute for Basic ScienceGwangjuRepublic of Korea institute of Radiation physics Helmholtz-Zentrum Dresden RossendorfDresdenGermany Beijing Laser Acceleration Innovation Center BeijingChina institute of Guangdong Laser Plasma Technology GuangzhouChina

To meet the demands of laser-ion acceleration at a high repetition rate,we have developed a comprehensive diagnostic system for real-time and in situ monitoring of liquid sheet targets(LSTs).The spatially resolved rapid characterizations of an LST’s thickness,flatness,tilt angle and position are fulfilled by different subsystems with high *** the help of the diagnostic system,we reveal the dependence of thickness distribution on collision parameters and report the 238-nm liquid sheet generated by the collision of two liquid *** methods for the flatness and tilt angle of LSTs have also been provided,which are essential for applications of laser-driven ion acceleration and others.

关键词： diagnostics laser-ion acceleration liquid sheet targets

In situ observation of the phase transformation kinetics of bismuth during shock release

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Chinese physics B 2024年第4期33卷 586-592页

作者：李江涛王倩男徐亮柳雷张航 Sota Takagi Kouhei Ichiyanagi Ryo Fukaya Shunsuke Nozawa 胡建波 laboratory for shock Wave and detonation physics Research Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China State key laboratory for Environment-Friendly Energy Materials Southwest University of Science and TechnologyMianyang 621010China Japan Society for the Promotion of Science Tokyo102-0083Japan institute of Materials Structure Science High Energy Accelerator Research OrganizationIbaraki305-8572Japan

A time-resolved x-ray diffraction technique is employed to monitor the structural transformation of laser-shocked *** reveal a retarded transformation from the shock-induced Bi-Ⅴphase to a metastable Bi-Ⅳphase during the shock release,instead of the thermodynamically stable Bi-Ⅲ*** emergence of the metastable Bi-Ⅳphase is understood by the competitive interplay between two transformation pathways towards the Bi-Ⅳand Bi-Ⅲ,*** former is more rapid than the latter because the Bi-Ⅴto B-Ⅳtransformation is driven by interaction between the closest atoms while the Bi-Ⅴto B-Ⅲtransformation requires interaction between the second-closest *** nucleation time for the Bi-Ⅴto Bi-Ⅳtransformation is determined to be 5.1±0.9 ns according to a classical nucleation *** observation demonstrates the importance of the formation of the transient metastable phases,which can change the phase transformation pathway in a dynamic process.

关键词： phase transformation time-resolved x-ray diffraction(XRD) bismuth metastable phase nonequilibrium phase diagram

Advances in the kinetics of heat and mass transfer in near-continuous complex flows

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Frontiers of physics 2024年第4期19卷 187-234页

作者：许爱国张德佳甘延标 national key laboratory of Computational physics Institute of Applied Physics and Computational MathematicsP.O.Box 8009-26Beijing 100088China State key laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China State key laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing 100083China national key laboratory of shock Wave and detonation physics Mianyang 621999China Hebei key laboratory of Trans-Media Aerial Underwater Vehicle School of Liberal Arts and SciencesNorth China Institute of Aerospace EngineeringLangfang 065000China

The study of macro continuous flow has a long ***,the exploration of heat and mass transfer in small systems with a particle number of several hundred or less has gained significant interest in the fields of statistical physics and nonlinear ***,due to absence of suitable methods,the understanding of mesoscale behavior situated between the aforementioned two scenarios,which challenges the physical function of traditional continuous fluid theory and exceeds the simulation capability of microscopic molecular dynamics method,remains considerably *** greatly restricts the evaluation of effects of mesoscale behavior and impedes the development of corresponding regulation *** access the mesoscale behaviors,there are two ways:from large to small and from small to *** the necessity to interface with the prevailing macroscopic continuous modeling currently used in the mechanical engineering community,our study of mesoscale behavior begins from the side closer to the macroscopic continuum,that is from large to *** on some fundamental challenges encountered in modeling and analysis of near-continuous flows,we review the research progress of discrete Boltzmann method(DBM).The ideas and schemes of DBM in coarse-grained modeling and complex physical field analysis are *** relationships,particularly the differences,between DBM and traditional fluid modeling as well as other kinetic methods are *** verification and validation of the method,some applied researches including the development of various physical functions associated with discrete and non-equilibrium effects are *** directions of DBM related studies are indicated.

关键词： near-continuous flow non-equilibrium kinetics discrete Boltzmann method complex physical field analysis

Photophysics of metal-organic frameworks:A brief overview

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Chinese physics B 2024年第1期33卷 122-133页

作者：刘晴硕余俊宏胡建波 State key laboratory for Environment-Friendly Energy Materials Southwest University of Science and TechnologyMianyang 621010China laboratory for shock Wave and detonation physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China

Metal-organic frameworks(MOFs),which are self-assembled porous coordination materials,have garnered considerable attention in the fields of optoelectronics,photovoltaic,photochemistry,and photocatalysis due to their diverse structures and excellent ***,the performance of MOF-based optoelectronic applications currently falls short of the industry *** enhance the performance of MOF materials,it is imperative to undertake comprehensive investigations aimed at gaining a deeper understanding of photophysics and sequentially optimizing properties related to photocarrier transport,recombination,interaction,and *** utilizing femtosecond laser pulses to excite MOFs,time-resolved optical spectroscopy offers a means to observe and characterize these ultrafast microscopic *** approach adds the time coordinate as a novel dimension for comprehending the interaction between light and ***,this review provides a comprehensive overview of the recent advancements in the photophysics of MOFs and additionally outlines potential avenues for exploring the time domain in the investigation of MOFs.

关键词： metal-organic framework(MOF) ultrafast spectroscopy photophysics carrier dynamics

Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan key laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China institute of fluid physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data

The dry-hot feedback between soil moisture and atmosphere and the accelerated global warming

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Science China Earth Sciences 2024年第3期67卷 890-891页

作者： Tianjun ZHOU State key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Greenhouse gas (GHG) emissions have been increasing due to human activities since the Industrial Revolution, resulting in continuous warming of the global climate system and significant drought over a large parts of global land, both have shown a non-linear growth trend in recent decades(Berg et al., 2017;Zhou et al., 2019;IPCC, 2021).

关键词： warming moisture drought

Domain wall network:A dual solution for gravitational waves and Hubble tension?

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Science China(physics,Mechanics & Astronomy) 2024年第11期67卷 39-46页

作者： Ligong Bian Shuailiang Ge Changhong Li Jing Shu Junchao Zong Department of physics and Chongqing key laboratory for Strongly Coupled physics Chongqing UniversityChongqing 401331China Center for High Energy physics Peking UniversityBeijing 100871China School of physics and State key laboratory of Nuclear physics and Technology Peking UniversityBeijing 100871China Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceSchool of Physics and AstronomyYunnan UniversityKunming 650091China Beijing Laser Acceleration Innovation Center Beijing 101400China Department of physics Nanjing UniversityNanjing 210093China CAS key laboratory of Theoretical physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We explore the possibility that domain wall networks generate the stochastic gravitational wave background(SGWB) observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar Timing Array. We find that a broad range of parameters, specifically wall tension around σ_(DW)^(29-414 TeV)^(3) and wall-decay temperature within T_(d) ~ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ΩGW(f_(p), T_(0))h^(2)~ Ω_(rad)h^(2)(Ω_νΩN_(eff))^(2),to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.

关键词： domain wall gravitational waves Hubble tension

Study on damage mechanism and damage distribution of the rear plate under impact of debris cloud

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Defence Technology（防务技术） 2024年第5期35卷 151-167页

作者： Chenyang Wu Xiaowei Chen Qiguang He State key laboratory of Explosion Science and Technology Beijing Institute of TechnologyHaidian DistrictBeijing 100081China School of Mechatronical Engineering Beijing Institute of TechnologyHaidian DistrictBeijing 100081China institute of fluid physics China Academy of Engineering PhysicsMianyang 621900SichuanChina

The debris cloud generated by the hypervelocity impact(HVI)of orbiting space debris directly threatens the spacecraft.A full understanding of the damage mechanism of rear plate is useful for the optimal design of protective *** this study,the hypervelocity yaw impact of a cylindrical aluminum projectile on a double-layer aluminum plate is simulated by the FE-SPH adaptive method,and the damage process of the rear plate under the impact of the debris cloud is analyzed based on the debris cloud *** damage process can be divided into the main impact stage of the debris cloud and the structural response of the rear *** main impact stage lasts a short time and is the basis of the rear plate *** the stage of structure response,the continuous deformation and inertial motion of the rear plate dominate the perforation of the rear *** further analyze the damage mechanism and damage distribution characteristics of the rear plate in ***,the connection between velocity space and position space of the debris cloud is established,which promotes the general analysis of the damage law of debris *** on the relationship,the features of typical damage areas are identified by the localized fine *** the cumulative effect and structural response cause the perforation of rear plate;in the non-perforated area,cratering by the impact of hazardous fragments is the main damage mode of the rear plate.

关键词： Damage of rear plate Debris cloud Secondary impact Hypervelocity yaw impact FE-SPH adaptive method

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie SONG State key laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term