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china Foundry 2024年第4期21卷 352-359页

作者： Zhen Zhang Lin-na Feng Jin-he wang zheng-kun Li Hua-meng Fu Hong Li zheng-wang zhu Hai-feng Zhang School of Materials Science and engineering Shenyang University of TechnologyShenyang 110870China 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 School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

Energy dissipation mechanism and ballistic characteristic optimization in foam sandwich panels against spherical projectile impact

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Defence Technology（防务技术） 2024年第5期35卷 108-122页

作者： Jianqiang Deng tao Liu Liming Chen Xin Pan Jingzhe wang Shaowei zhu Weiguo Li College of Aerospace engineering Chongqing UniversityChongqing 400030China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China Chongqing Key Laboratory of Heterogeneous Material Mechanics Chongqing UniversityChongqing 400030China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element *** on the geometric topology of the FSP system,three FSP configurations with the same areal density are derived,namely multi-layer,gradient core and asymmetric face sheet,and three key structural parameters are identified:core thickness(t_(c)),face sheet thickness(t_(f))and overlap face/core number(n_(o)).The ballistic performance of the FSP system is comprehensively evaluated in terms of the ballistic limit velocity(BLV),deformation modes,energy dissipation mechanism,and specific penetration energy(SPE).The results show that the FSP system exhibits a significant configuration dependence,whose ballistic performance ranking is:asymmetric face sheet>gradient core>*** mass distribution of the top and bottom face sheets plays a critical role in the ballistic resistance of the FSP *** BLV and SPE increase with tf,while the raising tcor noleads to an increase in BLV but a decrease in ***,a face-core synchronous enhancement mechanism is discovered by the energy dissipation analysis,based on which the ballistic optimization procedure is also conducted and a design chart is *** study shed light on the anti-penetration mechanism of the FSP system and might provide a theoretical basis for its engineering application.

关键词： Sandwich panel Numerical simulation Ballistic resistance Specific penetration energy Energy analysis

A function-based behavioral modeling method for air combat simulation

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Journal of systems engineering and Electronics 2024年第4期35卷 945-954页

作者： wang tao zhu Zhi ZHou Xin JING Tian CHEN Wei College of systems engineering National University of Defense TechnologyChangsha 410073China institute of Communication and Navigation Air Force Research AcademyBeijing 100085China

Today’s air combat has reached a high level of uncertainty where continuous or discrete variables with crisp values cannot be properly represented using fuzzy sets. With a set of membership functions, fuzzy logic is well-suited to tackle such complex states and actions. However, it is not necessary to fuzzify the variables that have definite discrete ***, the aim of this study is to improve the level of model abstraction by proposing multiple levels of cascaded hierarchical structures from the perspective of function, namely, the functional decision tree. This method is developed to represent behavioral modeling of air combat systems, and its metamodel,execution mechanism, and code generation can provide a sound basis for function-based behavioral modeling. As a proof of concept, an air combat simulation is developed to validate this method and the results show that the fighter Alpha built using the proposed framework provides better performance than that using default scripts.

关键词： air combat behavioral modeling intelligent agent

Toughening ultrastrong low-density steel by textured δ-ferrite lamellas

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Defence Technology（防务技术） 2024年第2期32卷 405-411页

作者： Bin Hu Guosen zhu Guohui Shen zheng wang Qinghua Wen Xiao Shen Haiwen Luo School of Metallurgical and Ecological engineering University of Science and Technology BeijingXue Yuan Rd.30Beijing 100083China Shougang Research institute of Technology Yangzhuang Street 69Beijing 100043China Steel institute RWTH Aachen UniversityIntzestraße 152072AachenGermany

By both the Charpy V-notched impact and the projectile tests, we here investigated the dynamic fracture behavior of a recently developed ultrastrong lightweight steel comprising a hierarchical martensitic matrix, dispersed ultra-fine-retained austenite grains and oriented δ-ferrite lamellas, the latter being due to high Al and Si contents employed for low-density design. This steel shows a superior combination of specific ultimate tensile strength and impact toughness to other ultrastrong steels and has successfully arrested a real steel-cored bullet shot. These are attributed to the densely textured δ-ferrite lamellas that can deflect the propagating cracks until they are trapped and enclosed besides austenite-to-martensite transformation crack closure, leading to more energy consumed before failure. These results suggest a new pathway for toughening ultrastrong lightweight steels.

关键词： Ultrastrong and light steel d-Ferrite lamellas Crack propagation Toughness

Dual-channel mechano-phosphorescence:a combined locking effect with twisted molecular structures and robust interactions

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Light(Science & Applications) 2024年第4期13卷 738-746页

作者： Zongliang Xie zhu Mao Hailan wang Yuxin Xiao Xiayu Zhang tao Yu Zhongfu An Wei Huang Frontiers Science Center for Flexible Electronics Xi’an Institute of Flexible Electronics&Xi’an Institute of Biomedical Materials and EngineeringNorthwestern Polytechnical University127 West Youyi RoadXi’an 710072China. Research&Development institute of Northwestern Polytechnical university in Shenzhen Shenzhen 518100China. Shenzhen institutes of Advanced Electronic Materials Shenzhen 518100China. Key Laboratory of Flexible Electronics&institute of Advanced Materials Nanjing Tech University30 South Puzhu RoadNanjing 211816China

Organic mechanoluminescence materials,featuring dual emission and ultralong phosphorescence characteristics,exhibit significant potential for applications in real-time stress sensing,pressure-sensitive lighting,advanced security marking techniques,and material breakage ***,due to immature molecular design strategies and unclear luminescence mechanisms,these materials remain rarely *** this study,we propose a valuable molecular design strategy to achieve dual-channel *** introducing the arylphosphine oxide group into a highly twisted molecular framework,enhanced intra-and intermolecular interactions could be achieved within rigid structures,leading to dual-channel mechanoluminescence with greatly promoted ultralong *** investigations reveal the substantial boosting effect of intra-and intermolecular interactions on mechanoluminescence and ultralong phosphorescence properties by locking the highly twisted molecular *** work provides a concise and guiding route to develop novel smart responsive luminescence materials for widespread applications in material science.

关键词： channel luminescence locking

PVDF/6H-SiC composite fiber films with enhanced piezoelectric performance by interfacial engineering for diversified applications

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Journal of Materials Science & Technology 2024年第3期170卷 238-245页

作者： Linlin Zhou tao Yang Chunyu Guo Kang wang Enhui wang Laipan zhu Hailong wang Sheng Cao Kuo-Chih Chou Xinmei Hou institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Beijing institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Materials Science engineering Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China

Piezoelectric silicon carbide(SiC)has been quite attractive due to its superior chemical and physical properties as well as wide potential ***,the inherent brittleness and unsatisfactory piezoelectric response of piezoelectric semiconductors remain the major obstacles to their diversified ***,flexible multifunctional PVDF/6H-SiC composite fiber films are fabricated and utilized to assemble both piezoelectric nanogenerators(PENGs)and stress/temperature/light *** open cir-cuit voltage(V_(oc))and the density of short circuit current(I_(sc))of the PENG based on the PVDF/5 wt%6H-SiC composite fiber films reach 28.94 V and 0.24μA cm^(-2),showing a significant improvement of 240%and 300%compared with that based on the pure PVDF *** effect of 6H-SiC nanoparticles(NPs)on inducing interfacial polarization and stress concentration in composite fiber films is proved by first-principles calculation and finite element *** stress/temperature/light sensors based on the composite fiber film also show high sensitivity to the corresponding *** study shows that the PVDF/6H-SiC composite fiber film is a promising candidate for assembling high-performance energy harvesters and diverse sensors.

关键词： 6H-SiC PVDF Multifunctional composite fiber film Energy harvester Stress/temperature/light sensor

Defect-manipulated magnetoresistance and above-room-temperature ferromagnetism in two-dimensional BaNi_(2)V_(2)O_(8)

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Chinese Chemical Letters 2024年第3期35卷 523-527页

作者： Pengfei Tan Chuanhui zhu Jinjin Yang Shuang Zhao tao Xia Mei-Huan Zhao tao Han zheng Deng Man-Rong Li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhou 510006China School of Science and engineering The Chinese University of Hong KongShenzhen 518172China institute of Physics Chinese Academy of SciencesBeijing 100190China School of Science Hainan UniversityHaikou 570228China

The intricate correlation between multiple degrees of freedom and physical properties is a fascinating area in solid state chemistry and condensed matter ***,we report a quantum-magnetic system BaNi_(2)V_(2)O_(8)(BNVO),in which the spin correlation was modulated by unusual oxidation state,leading to different magnetic *** BNVO was modified with topochemical reduction(TR)to yield TR-BNVO with partially reduced valance state of Ni^(+)in the two-dimensional NiO_(6)-honeycomb ***,the antiferromagnetic order is suppressed by the introduction of locally interposed Ni^(+)and oxygen vacancies,resulting in a ferromagnetic ground state with the transition temperature up to 710 K.A positive magnetoresistance(7.5%)was observed in the TR-BNVO at 40 K under 7 *** findings show that topological reduction is a powerful approach to engineer low-dimensional materials and accelerate the discovery of new quantum magnetism.

关键词： Layered honeycomb oxide Topochemical reduction Oxygen vacancies Ferromagnetism Magnetoresistance

BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

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Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： Zhi-Jun wang Si-Sheng wang zheng-Huang Su Li Yu Yu-zhu wang Bo Sun Wen Wen Xing-Yu Gao Shanghai Advanced Research institute Chinese Academy of SciencesShanghai201210China university of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline(BL03HB) was constructed at the Shanghai Synchrotron Radiation Facility(SSRF).This beamline features two consecutive focusing points in two different sectors within its end station, the first dedicated to protein crystallography and the other tailored to materials science applications. Based on a superbend dipole magnet with a magnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick-Baez mirrors to achieve a micro white beam as small as 4.2 μ m ×4.3 μ m at the first sector and 0.9 μ m ×1.3 μ m at the second sector in the standard beamline operation mode at SSRF. The X-ray microbeam in the two sectors can be easily switched between monochromatic and white beams by moving a four-bounce monochromator in or out of the light path, respectively. In the protein crystallography sector, white-beam Laue microdiffraction was demonstrated to successfully determine the structure of protein crystals from only a few images of diffraction data collected by a Pilatus 2 M area detector. In the materials science sector,the white-beam Laue diffraction was collected in a reflection geometry using another Pilatus 2 M area detector, which could map the microstructural distribution on the sample surface by scanning the samples. In general, the BL03HB beamline promotes the application of Laue microdiffraction in both protein crystallography and materials science. This paper presents a comprehensive overview of the BL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

Spectral-interferometry-based diff-iteration for high-precision micro-dispersion measurement

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Photonics Research 2024年第6期12卷 1362-1370页

作者： WEI DU JINGSHENG HUANG YANG wang MAOZHONG ZHAO JUAN LI JUNtao HE JINDONG wang WENFU ZHANG tao zhu Key Laboratory of Optoelectronic Technology&System(Ministry of Education) Chongqing UniversityChongqing 400044China State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China

Precise measurement of micro-dispersion for optical devices(optical fiber,lenses,etc.)holds paramount significance across domains such as optical fiber communication and dispersion interference ***,due to its complex system,complicated process,and low reliability,the traditional dispersion measurement methods(interference,phase shift,or time delay methods)are not suitable for the accurate measurement of micro-dispersion in a wide spectral ***,we propose a spectral-interferometry-based diff-iteration(SiDi)method for achieving accurate wide-band micro-dispersion *** an optical frequency comb,based on the phase demodulation of the dispersion interference spectrum,we employ the carefully designed SiDi method to solve the dispersion curve at any position and any *** approach is proficient in precisely measuring micro-dispersion across a broadband spectrum,without the need for cumbersome wavelength scanning processes or reliance on complex high-repetition-rate combs,while enabling adjustable *** efficacy of the proposed method is validated through simulations and *** employed a chip-scaled soliton microcomb(SMC)to compute the dispersion curves of a 14 m single-mode fiber(SMF)and a 0.05 m *** to a laser interferometer or the theoretical value given by manufacturers,the average relative error of refractive index measurement for single-mode fiber(SMF)reaches 2.8×10^(-6) and for glass reaches 3.8×10^(-6).The approach ensures high precision,while maintaining a simple system structure,with realizing adjustable resolution,thereby propelling the practical implementation of precise measurement and control-dispersion.

关键词： interferometer dispersion iteration

Nonlinear change of ion-induced secondary electron emission in theκ-Al_(2)O_(3) surface charging from first-principle modelling

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Plasma Science and Technology 2024年第9期26卷 40-50页

作者： Zhicheng JIAO Mingrui zhu Dong DAI tao SHAO Buang wang South china university of Technology Guangzhou 510641People’s Republic of China institute of Electrical engineering Chinese Academy of SciencesBeijing 100190People’s Republic of China university of Richmond Richmond 23173United States of America

Secondary electron emission(SEE)induced by the positive ion is an essential physical process to influence the dynamics of gas discharge which relies on the specific surface *** charging has a significant impact on the material properties,thereby affecting the SEE in the plasma-surface ***,it does not attract enough attention in the previous *** this paper,SEE dependent on the charged surface of specific materials is described with the computational method combining a density functional theory(DFT)model from the first-principle theory and the theory of Auger *** effect ofκ-Al2O3 surface charge,as an example,on the ion-induced secondary electron emission coefficient(SEEC)is investigated by analyzing the defect energy level and band structure on the charged *** results indicate that,with the surface charge from negative to positive,the SEEC of a part of low ionization energy ions(such as Ei=12.6 eV)increases first and then decreases,exhibiting a nonlinear changing *** is quite different from the monotonic decreasing tendency observed in the previous model which simplifies the electronic *** irregular increase of the SEEC can be attributed to the lower escaped probability of orbital *** results further illustrate that the excessive charge could cause the bottom of the conduction band close to the valence band,thus leading to the decrease of the orbital energy occupied by the excited *** nonlinear change of SEEC demonstrates a more realistic situation of how the electronic structure of material surface influences the SEE *** work provides an accurate method of calculating SEEC from specific materials,which is urgent in widespread physical scenarios sensitive to surface materials,such as increasingly growing practical applications concerning plasma-surface interactions.

关键词： secondary electron emission charged surface density functional theory defect energy level