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Effect of ablation on the nonlinear spike growth for the single-mode ablative Rayleigh-Taylor instability

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Matter and Radiation at Extremes 2023年第1期8卷 53-62页

作者： J.Y.Fu H.s.Zhang H.B.Cai p.L.Yao s.p.zhu Institute of Applied physics and Computational Mathematics Beijing 100088People’s Republic of China Laboratory of Computational physics Institute of Applied Physics and Computational MathematicsBeijing 100088People’s Republic of China Graduate school China Academy of Engineering PhysicsP.O.Box 2101Beijing 100088People’s Republic of China science and Technology on plasma physics Laboratory Laser Fusion Research CenterCAEPMianyang 621900People’s Republic of China

The effect of ablation on the nonlinear spike growth of single-mode ablative Rayleigh–Taylor instability(RTI)is studied by two-dimensional numerical *** is shown that the ablation can reduce the quasi-constant velocity and significantly suppress the reacceleration of the spike in the nonlinear *** is also shown that the spike growth can affect the ablation-generated vorticity inside the bubble,which further affects the nonlinear bubble *** vorticity evolution is found to be correlated with the mixing width(i.e.,the sum of the bubble and spike growths)for a given wave number and ablation *** considering the effects of mass ablation and vorticity,an analytical model for the nonlinear bubble and spike growth of single-mode ablative RTI is developed in this *** is found that the nonlinear growth of the mixing width,induced by the single mode,is dominated by the bubble growth for small-scale ablative RTI,whereas it is dominated by the spike growth for classical RTI.

关键词： phase nonlinear bubble

palladium-catalyzed s_(N)2 glycosylation of phenols

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science China Chemistry 2024年第4期67卷 1037-1038页

作者： Yu zhu p.Andrew Evans Department of Chemistry Queen’s University90 Bader LaneKingstonK7L 3N6Canada Xiangya school of pharmaceutical sciences Central South UniversityChangsha 410013China

Glycosides are essential structural motifs present in an array of important medicines,materials,and natural products[1].Nevertheless,the chemo-and stereoselective construction of the glycosidic linkage is a long-standing challenge because relatively minor variations in the glycosyl donor or acceptor’s structure can impact stereoselectivity,thus influencing the product's functional properties.

关键词： properties palladium catalyzed

Generation mechanism of 100 MG magnetic fields in the interaction of ultra-intense laser pulse with nanostructured target

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High power Laser science and Engineering 2020年第2期8卷 50-55页

作者： J.M.Tian H.B.Cai W.s.Zhang E.H.Zhang B.Du s.p.zhu Graduate school China Academy of Engineering PhysicsBeijing 100088China Institute of Applied physics and Computational Mathematics Beijing 100094China Center for Applied physics and Technology HEDPSand College of EngineeringPeking UniversityBeijing 100871China

Experimental and simulation data[Moreau et al.,plasma *** 62,014013(2019);Kaymak et al.,***.117,035004(2016)]indicate that self-generated magnetic fields play an important role in enhancing the flux and energy of relativistic electrons accelerated by ultra-intense laser pulse irradiation with nanostructured arrays.A fully relativistic analytical model for the generation of the magnetic field based on electron magneto-hydrodynamic description is presented *** analytical model shows that this self-generated magnetic field originates in the nonparallel density gradient and fast electron current at the interfaces of a nanolayered target.A general formula for the self-generated magnetic field is found,which closely agrees with the simulation scaling over the relevant intensity *** result is beneficial to the experimental designs for the interaction of the laser pulse with the nanostructured arrays to improve laser-to-electron energy coupling and the quality of forward hot electrons.

关键词： nanolayered target self-generated magnetic field ultra-intense laser pulse

Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures

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International Journal of Extreme Manufacturing 2024年第1期6卷 328-338页

作者： Qiang Liu Wei Xu Xiaoxi Li Tongyao Zhang Chengbing Qin Fang Luo Zhihong zhu shiqiao Qin Mengjian zhu Kostya s Novoselov College of Advanced Interdisciplinary studies&Hunan provincial Key Laboratory of Novel Nano-optoelectronic Information Materials and Devices National University of Defense TechnologyChangshaHunan 410073People’s Republic of China Nanhu Laser Laboratory National University of Defense TechnologyChangshaHunan 410073People’s Republic of China state Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006People’s Republic of China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006People’s Republic of China state Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006People’s Republic of China Institute for Functional Intelligent Materials National University of SingaporeSingapore 117544Singapore Department of Materials science and Engineering National University of SingaporeSingapore 117575Singapore

Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and *** record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter which can be further integrated into arbitrary platforms by van der Waals ***,due to the zero bandgap,graphene is difficult to emit light through the interband recombination of carriers like conventional ***,we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride(Gr/hBN)*** in biased graphene are significantly heated up to 2800 K at modest electric fields,emitting bright photons from the near-infrared to the visible spectral *** eliminating the heat dissipation channel of the substrate,the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on siO2or *** demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal *** cooling ofhigh-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface,resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical *** is found thatsuspending the Gr/hBN heterostructures on the siO2trenches significantly modifies the light emission due to the formation of the optical cavity and showed a~440%enhancement inintensity at the peak wavelength of 940 nm compared to the black-body thermal *** demonstration of electrically driven ultrafast light emission from suspended Gr/hBNheterostructures sheds the light on applications of graphene heterostructures in photonicintegrated circuits,such as broadband light sources and ultrafast thermo-optic phase modulat

关键词： suspended graphene ultrafast light emitter van der Waals heterostructures thermal radiation electron–phonon interaction

Few-shot incremental radar target recognition framework based on scattering-topology properties

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Chinese Journal of Aeronautics 2024年第8期37卷 246-260页

作者： Chenxuan LI Weigang zhu Bakun zhu Yonggang LI Graduate school Space Engineering UniversityBeijing 101400China Department of Electronic and Optical Engineering Space Engineering UniversityBeijing 101400China

The continuous emergence of new targets in open scenarios leads to a substantial decrease in the performance of Inverse synthetic Aperture Radar(IsAR)recognition ***,data scarcity further exacerbates the challenge of identifying new classes of IsAR *** this paper,a few-shot incremental target recognition framework based on scattering-Topology properties(sTpIL)is ***,sTpIL extracts scattering-topology properties of IsAR targets as recognition ***,the pseudo-incremental training strategy effectively alleviates the algorithm’s forgetting of old knowledge,and improves compatibility with new ***,a feature embedding network,with few parameters,is designed based on the graph neural *** embedding network is highly adaptable to changes in data ***,sTpIL fully considers the joint distribution and marginal distribution in scattering features,and uses the Brownian distance metric module to make the scattering-topology features more *** results on both the simulation dataset and the public measured data indicate that sTpIL can effectively balance new classes with old classes,and has superior performance to other advanced methods in the incremental recognition of targets.

关键词： Brownian distance metric Graph neural networks Incremental learning Inverse synthetic Aperture Radar(IsAR) scattering

Old pinus massoniana forests benefit more from recent rapid warming in humid subtropical areas of central-southern China

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Journal of Forestry Research 2024年第5期35卷 155-170页

作者： Wenxin Li Liangjun zhu Lianhua zhu Mengdan Jing Censhi Qian Yu zhu paolo Cherubini College of Life science and Technology Central South University of Forestry and TechnologyChangsha 410004People’s Republic of China swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland Department of Forest and Conservation sciences Faculty of ForestryUniversity of British Columbia2004-2424 Main MallVancouverBC V6T 1Z4Canada

Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental *** the importance of age-related growth responses on overall forest health and management policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree *** this study,we employed a den-drochronological method to examine the impact of rapid warming on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)pinus mas-soniana forests across six sites in central-southern *** normalized log basal area increment of trees in both age groups increased significantly following rapid warming in *** in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth *** growth was more strongly influenced by temperature than by moisture,particularly in old *** tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young *** forests had a significantly lower resistance to extreme drought but faster recovery compared to young ***“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warming-induced drought and heat *** ongoing warming,young forests also may initially experience a growth decline due to their heightened sensitivity to winter *** findings underscore the importance of considering age-dependent changes in forest/tree growth response to warming in subtropical forest man-agement,particularly in the context of achieving“Carbon peak&Carbon Neutrality”goals in China.

关键词： Tree rings pinus massoniana Age effects Drought resilience subtropical forests Rapid warming

paving the way toward soil safety and health:current status,challenges,and potential solutions

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Frontiers of Environmental science & Engineering 2024年第6期18卷 63-73页

作者： Chiheng Chu Lizhong zhu College of Environmental and Resource sciences Zhejiang UniversityHangzhou 310058China

soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon ***,the health of soil faces global threats from human activities,particularly widespread contamination by industrial *** physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional *** solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale ***,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of ***,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring *** the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

关键词： soil safety and health source emission reduction process monitoring and simulation Green remediation technology soil health management

A proof system of the CaIT calculus

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Frontiers of Computer science 2024年第2期18卷 123-137页

作者： Ningning CHEN Huibiao zhu shanghai Key Laboratory of Trustworthy Computing East China Normal UniversityShanghai 200062China

The Internet of Things(IoT)can realize the interconnection of people,machines,and things anytime,*** of the existing research mainly focuses on the practical applications of IoT,and there is a lack of research on modeling and reasoning about IoT systems from the perspective of formal ***,the Calculus of the Internet of Things(CaIT)has been proposed to specify and analyze IoT systems before the actual implementation,which can effectively improve development efficiency,and enhance system quality and *** verify the correctness of IoT systems described by CaIT,this paper presents a proof system for CaIT,in which specifications and verifications are based on the extended Hoare Logic with ***,we explore the cooperation between isolated proofs to validate the postconditions of the communication actions occurring in these proofs,with a particular focus on broadcast *** also demonstrate the soundness of our proof system.A simple“smart home”is given to illustrate the availability of our proof system.

关键词： Internet of Things(loT) Calculus of the Internet of Things(CalT) extended hoare logic cooperation smart home

Efficient Removal of phosphate from Aqueous solutions Using Corundum-hollow-spheres supported Caclined Hydrotalcite porous Thin Films

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Journal of Wuhan University of Technology(Materials science) 2024年第1期39卷 44-49页

作者：刘云才 zhu Chen school of Architecture and Materials Engineering Hubei Second Normal UniversityWuhan 430205China

phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. Mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (sEM).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal