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ChinAfrica 2024年第8期16卷 31-33页

作者： tIAN JIEtANG LUO LIPING MA sHUAN GU YAN LI YUJU Industrial Economics Department Development Research Centre of the State Council research Institute for Regional Economy and Ecological Development Hunan Academy of Social Sciences specialised Committee on International Cooperation and science and technology Diplomacy chinese association for science of science and s&t policy research Xi Jinping Economic thought research Centre National Development and Reform Commission

In recent years,China has made remarkable technological progress in a number of *** this progress,it is crucial to rapidly transform technological results into productivity gains.

关键词： technological cooperation remarkable

Multi-layer phenomena in petawatt laser-driven acceleration of heavy ions

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Plasma science and technology 2024年第2期26卷 70-76页

作者：苏琬晴曹喜光马春旺王玉廷张国强 College of Physics Henan Normal UniversityXinxiang 453007People's Republic of China shanghai Advanced research Institute Chinese Academy of SciencesShanghai 201210People's Republic of China shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800People's Republic of China University of chinese Academy of sciences Bejing 100049People's Republic of China Institute of Nuclear science and technology Henan Academy of ScienceZhengzhou 450046People's Republic of China

Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators.A particle-in-cell program(smilei) is employed to simulate the entire process of station of Extreme Light(sEL) 100 PW laser-accelerated heavy particles using different nanoscale short targets with a thickness of 100 nm Cr, Fe, Ag, ta, Au, Pb, th and U, as well as 200 nm thick Al and Ca. An obvious stratification is observed in the simulation. the layering phenomenon is a hybrid acceleration mechanism reflecting target normal sheath acceleration and radiation pressure acceleration, and this phenomenon is understood from the simulated energy spectrum,ionization and spatial electric field distribution. According to the stratification, it is suggested that high-quality heavy-ion beams could be expected for fusion reactions to synthesize superheavy nuclei. two plasma clusters in the stratification are observed simultaneously, which suggest new techniques for plasma experiments as well as thinner metal targets in the precision machining process.

关键词： petawatt laser-plasma interaction laser-driven heavy-ion accelerator for synthesizing superheavy nuclei particle-in-cell multi-layer phenomena target fabrication

Facile preparation of a siC@siO_(2)nanowire-toughened ZrB_(2)-siC/siC bilayer coating with good interfacial bonding,high toughness,and excellent cyclic ablation resistance on C/CA composites

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Journal of Advanced Ceramics 2024年第4期13卷 486-495页

作者： Meng Yan Chenglong Hu Jian Li shengyang Pang Bohui sun Rida Zhao Bin Liang Rui Luo sufang tang shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China

Preparing antioxidant coatings to address the inherent oxidation sensitivity of carbon fiber-reinforced carbon aerogel(C/CA)composites is a feasible way to promote their application in oxidizing environments as thermal insulation ***,preparing the coatings with excellent oxidation and ablation resistance while avoiding evident damage to the C/CA substrate still remains a ***,a siC@siO_(2)nanowire-toughened ZrB2–siC/siC bilayer coating with a large thickness of 500μm was prepared on C/CA using a one-step low-temperature reaction sintering method,which simultaneously formed a sintered outer layer with even-distributed nanowires and a siliconized gradient inner *** courtesy of the synergic thermal response of the layers and the crack deflection induced by the nanowires,the resulting coating has moderate residual compressive stress of 0.08–1.22 GPa in the interface,high interfacial bonding strength of 6.02 MPa,and good fracture toughness of 4.36 MPa·m^(1/2).Benefited from the optimum components and improved structure,the coating shows excellent cyclic ablation resistance with linear ablation rates of 0.1μm/s at 1650℃for 1500 s(300 s×5 cycles)and 0.4μm/s at 1850℃for 900 s(300 s×3 cycles).the one-step preparation strategy contributes to little damage to the substrate,thus showing the well-preserved mechanical and thermal insulation properties.

关键词： coating carbon fiber reinforced carbon aerogel(C/CA)composites toughness interface residual stress

Observation of Doppler shift f_(D) modulated by the internal kink mode using conventional reflectometry in the EAst tokamak

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Plasma science and technology 2024年第3期26卷 1-9页

作者：李恭顺张涛耿康宁文斐叶凯萱徐立清朱翔张学习钟富彬周振杨书琪周子强喻琳兰婷王守信提昂张寿彪刘海庆李国强高翔 the EAst team Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People's Republic of China Advanced Energy research Center Shenzhen UniversityShenzhen 518060People's Republic of China University of science and technology of China Hefei 230026People's Republic of China

In this paper we present a new experimental observation using a conventional reflectometry technique,poloidal correlation reflectometry(PCR),in the Experimental Advanced superconducting tokamak(EAst).the turbulence spectrum detected by the PCR system exhibits an asymmetry and induced Doppler shift f_(D)during the internal kink mode(IKM)rotation *** Doppler shift f_(D)is the target measurement of Doppler reflectometry,but captured by conventional *** show that the Doppler shift f_(D)is modulated by the periodic changes in the effective angle between the probing wave and cutoff layer normal,but not by plasma *** fishbone mode and saturated long-lived mode are typical IKMs,and this modulation phenomenon is observed in both ***,the value of the Doppler shift f_(D)is positively correlated with the amplitude of the IKM,even when the latter is ***,the positive and negative frequency components of the Doppler shift f_(D)can be asymmetric,which is related to the plasma configuration.A simulated analysis is performed by ray tracing to verify these *** results establish a clear link between f_(D)and IKM rotation,and are helpful for studying the characteristics of IKM and related physical phenomena.

关键词： microwave reflectometry Doppler shift internal kink mode

Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause

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Earth and Planetary Physics 2024年第1期8卷 133-154页

作者： RongCong Wang JiaQi Wang DaLin Li tianRan sun XiaoDong Peng YiHong Guo National space science Center Chinese Academy of SciencesBeijing 100190China University of chinese Academy of sciences Beijing100049China Aerospace Information research Institute Chinese Academy of SciencesBeijing 100094China

Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space *** soft X-ray Imager(sXI)carried by the solar wind Magnetosphere Ionosphere Link Explorer(sMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray ***,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the *** analysis of sXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration *** makes it difficult to establish the mapping relationship between sXIsimulated observation images and target images by using mathematical *** propose an image restoration algorithm for sXIsimulated observation images that can recover large-scale structure information on the *** idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the sXI-simulated observation image,whose mapping relationship with the target image is established by the patch *** Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the *** results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the sXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural *** restoration results of sXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving

关键词： solar wind Magnetosphere Ionosphere Link Explorer(sMILE) soft X-ray imager magnetopause image restoration

the centrosymmetric to non-centrosymmetric transformation induced by alkaline-earth cations producing infrared nonlinear optical AeMn6Ga6s16（Ae = Ca, sr）

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science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang shao-Min Pei Wen-Fa Chen Bin-Wen Liu Xiao-Ming Jiang Guo-Cong Guo state Key Laboratory of structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences school of Physical science and technology Shanghai Tech University Fujian science & technology Innovation Laboratory for Optoelectronic Information of China

Non-centrosymmetric（NCs） structure is an indispensable prerequisite for second-order nonlinear optical（NLO） ***, the mainstream approach for designing new NCs structures still relies on chemical substitution, necessitating an urgent infusion of fresh ideas. In this work, two isomorphic sulfides AeMn6Ga6s16（Ae = Ca, 1; sr, 2） are afforded by modifying the skeleton of centrosymmetric（Cs） Mn2Ga2s5via introducing strong electropositive alkaline-earth cations. Concretely, the incorporation of Ca2+/sr2+cations allows the elementary [MnGas9]∞chains to reconfigure into bumpy [Mns6]-[Gas4] layers in a new engagement manner, thus enabling the conversion from Cs to NCs structure. such modifications cause not only strong second-harmonic generation（sHG） responses（～1.5 × benchmark AgGas2@1,700 nm）, but also significantly feasible bandgaps（2.60–2.64 e V） compared to the sulfide Mn2Ga2s5（1.36 e V）, which ultimately facilitate ultrahigh laser-induced damage thresholds（4.4–6.6 × AgGas2@1,064 nm for compounds 1 and 2）. the present study offers an ingenious approach for the transformation of Cs to NCs structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

Cloud top Pressure Retrieval Using Polarized and Oxygen A-band Measurements from GF5 and PARAsOL satellites

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Advances in Atmospheric sciences 2024年第4期41卷 680-700页

作者： Lesi WEI Huazhe sHANG Jian XU Chong sHI Gegen tANA Kefu CHAO shanhu BAO Liangfu CHEN Husi LEtU state Key Laboratory of Remote sensing science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China National space science Center Chinese Academy of SciencesBeijing 101407China College of Physics and Electronic Information Inner Mongolia Normal UniversityHohhot 010022China College of Geographical science Inner Mongolia Normal UniversityHohhot 010022China University of chinese Academy of sciences Beijing 100101China

Cloud top pressure(CtP)is one of the critical cloud properties that significantly affects the radiative effect of ***-angle polarized sensors can employ polarized bands(490 nm)or O_(2)A-bands(763 and 765 nm)to retrieve the ***,the CtP retrieved by the two methods shows inconsistent results in certain cases,and large uncertainties in low and thin cloud retrievals,which may lead to challenges in subsequent *** study proposes a synergistic algorithm that considers both O_(2)A-bands and polarized bands using a random forest(RF)*** CtP data are used as the true values and the polarized and non-polarized measurements are concatenated to train the RF model to determine ***,through analysis,we proposed that the polarized signal becomes saturated as the cloud optical thickness(COt)increases,necessitating a particular treatment for cases where COtto improve the algorithm's *** synergistic method was then applied to the directional polarized camera(DPC)and Polarized and Directionality of the Earth’s Reflectance(POLDER)measurements for evaluation,and the resulting retrieval accuracy of the POLDER-based measurements(RMsEPOLDER=205.176 hPa,RMsEDPC=171.141 hPa,R^(2)POLDER=0.636,R^(2)DPC=0.663,respectively)were higher than that of the MODIs and POLDER Rayleigh pressure *** synergistic algorithm also showed good performance with the application of DPC *** algorithm is expected to provide data support for atmosphere-related fields as an atmospheric remote sensing algorithm within the Cloud Application for Remote sensing,Atmospheric Radiation,and Updating Energy(CARE)platform.

关键词： atmospheric remote sensing cloud top pressure multi-angle polarized O_(2)A-band GF-5/DPC PARAsOL/POLDER-3

Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of sHINE

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Nuclear science and techniques 2024年第2期35卷 20-31页

作者： Yong-Fang Liu Rui-Ping Wang Jin tong Bo Zhang si Chen Qi-Bing Yuan Hai-Xiao Deng Ming Gu Bo Liu shanghai Advanced research Institute Chinese Academy of SciencesShanghai 201412People’s Republic of China

the shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(sHINE)operates at a maximum repetition rate of 1 *** magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch *** kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn *** full magnetic field strength was 0.005 *** paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker *** relevant experimental results are also *** pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 *** developed kicker satisfies the requirements for the sHINE ***,numerous recommendations for the future optimization of kicker magnets are provided.

关键词： X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites

the influence of boundary conditions on the distribution of energetic electrons during collisionless magnetic reconnection

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Plasma science and technology 2024年第4期26卷 79-84页

作者：王磊黄灿陈冬可杨忠炜杜爱民葛亚松 CAs Engineering Laboratory for Deep Resources Equipment and technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People’s Republic of China College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100029People’s Republic of China state Key Laboratory of space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190People’s Republic of China

We conducted 2-D particle-in-cell simulations to investigate the impact of boundary conditions on the evolution of magnetic reconnection. the results demonstrate that the boundary conditions are crucial to this evolution. specifically, in the cases of traditional periodic boundary(PB) and fully-opened boundary(OB) conditions, the evolutions are quite similar before the system achieves the fastest reconnection rate. However, differences emerge between the two cases afterward. In the PB case, the reconnection electric field experiences a rapid decline and even becomes negative, indicating a reversal of the reconnection process. In contrast, the system maintains a fast reconnection stage in the OB case. suprathermal electrons are generated near the separatrix and in the exhaust region of both simulation cases. In the electron density depletion layer and the dipolarization front region, a larger proportion of suprathermal electrons are produced in the OB case. Medium-energy electrons are mainly located in the vicinity of the X-line and downstream of the reconnection site in both cases. However, in the OB case, they can also be generated in the electron holes along the separatrix. Before the reverse reconnection stage, no high-energy electrons are present in the PB case. In contrast, about 20% of the electrons in the thin and elongated electron current layer are high-energy in the OB case.

关键词： magnetic reconnection electron energization particle-in-cell simulation

the study of intelligent algorithm in particle identification of heavy-ion collisions at low and intermediate energies

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Nuclear science and techniques 2024年第2期35卷 170-182页

作者： Gao-Yi Cheng Qian-Min su Xi-Guang Cao Guo-Qiang Zhang school of Electronic and Electrical Engineering Shanghai University of Engineering ScienceShanghai 201620China shanghai Advanced research Institute Chinese Academy of SciencesShanghai 201210China shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

traditional particle identification methods face timeconsuming,experience-dependent,and poor repeatability challenges in heavy-ion collisions at low and intermediate *** urgently need solutions to the dilemma of traditional particle identification *** study explores the possibility of applying intelligent learning algorithms to the particle identification of heavy-ion collisions at low and intermediate *** intelligent algorithms,including XgBoost and tabNet,were selected to test datasets from the neutron ion multi-detector for reaction-oriented dynamics(NIMROD-Isis)and Geant4 ***-based machine learning algorithms and deep learning algorithms *** show excellent performance and generalization *** additional data features besides energy deposition can improve the algorithm’s performance when the data distribution is *** learning algorithms can be applied to solve the particle identification problem in heavy-ion collisions at low and intermediate energies.

关键词： Heavy-ion collisions at low and intermediate energies Machine learning Ensemble learning algorithm Particle identification Data imbalance