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Defence Technology（防务技术） 2024年第5期35卷 18-46页

作者： man Xu Nanxi xiang Ping Yin Qi Lai Siping Pang School of Materials Science&Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open *** the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark *** methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich ***,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic *** this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials.

关键词： Energetic materials Alkyl bridge strategy Nitrogen-rich azoles Fused heterocycles Azoles

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Review of dynamics and active control of large-scale space membrane antenna

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Astrodynamics 2024年第1期8卷 1-26页

作者： xiang liu Guoping Cai Department of Engineering Mechanics MOE Key Laboratory of HydrodynamicsChongqing Research InstituteShanghai Jiao Tong UniversityShanghai200240China

Large-scale space membrane antennas have significant potential in satellite communication,space-based early warning,and Earth *** of their large size and high flexibility,the dynamic analysis and control of membrane antenna are *** maintain the working performance of the antenna,the pointing and surface accuracies must be strictly ***,the accurate dynamic modeling and effective active control of large-scale space membrane antennas have great theoretical significance and practical value,and have attracted considerable interest in recent *** paper reviews the dynamics and active control of large-scale space membrane ***,the development and status of large-scale space membrane antennas are ***,the key problems in the dynamics and active control of large membrane antennas,including the dynamics of wrinkled membranes,large-amplitude nonlinear vibration,nonlinear model reduction,rigid-flexible-thermal coupling dynamic modeling,on-orbit modal parameter identification,active vibration control,and wave-based vibration control,are discussed in ***,the research outlook and future trends are presented.

关键词： large-scale space membrane antenna dynamicmodeling active control

Simulation of a soft-gamma-ray polarimeter on board a microsatellite

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Nuclear Science and Techniques 2023年第11期34卷 64-76页

作者： xiang‑man liu Shu‑Wen Tang Wei Wang Yu‑Hong Yu Zhi‑Yu Sun Yong‑Jie Zhang Fang Fang Duo Yan Shi‑Tao Wang Xue‑Heng Zhang Shu‑Ya Jin Bi‑Tao Hu Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Department of Astronomy School of Physics and TechnologyWuhan UniversityWuhan 430072China Wuhan University‑National Astronomical Observatories Joint Center for Astronomy Wuhan UniversityWuhan 430072China

Gamma-ray polarimetry is a new and prospective tool for studying extremely high-energy celestial objects and is of great significance for the field of *** the rapid development of microsatellite technology,the advantages of space exploration have become increasingly ***,we simulated a soft-gamma-ray polarimeter for a microsatellite based on the Compton scattering *** performed detailed Monte Carlo simulations using monoenergetic gamma-ray linear-polarization sources and Crab-like sources in the energy range of 0.1-10 MeV considering the orbital *** polarimeter exhibited excellent polarization detection *** modulation factor was 0.80±0.01,and the polarization angles were accurate within an error of 0.2°at 200 keV for on-axis *** the Crab-like sources for on-axis incidence,the polarization degrees were consistent with the set values within the error tolerance,the modulation factor was 0.76±0.01,and the minimum detectable polarization reached 2.4%at 3σfor an observation time of10^(6) ***,the polarimeter exhibited recoil electron tracking,imaging,and powerful background suppression in a large field of view(FoV;∼2πsr).The proposed polarimeter meets the requirements of a space soft-gamma-ray polarization detector and has promising research prospects.

关键词： Soft gamma ray Polarization Compton scattering Microsatellite Monte Carlo simulation

Removal of Cr(Ⅵ)by glutaraldehyde-crosslinked chitosan encapsulating microscale zero-valent iron:Synthesis,mechanism,and longevity

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Journal of Environmental Sciences 2024年第8期142卷 115-128页

作者： Yijun Duan Fang liu xiang liu Miao Li School of Environment Tsinghua UniversityBeijing 100084China Transportation Institute of Inner Mongolia University Hohhot 010070China

Microscale zero-valent iron(mZVI)has shown great potential for groundwater Cr(Ⅵ)***,low Cr(Ⅵ)removal capacity caused by passivation restricted the wide use of *** prepared mZVI/GCS by encapsulating mZVI in a porous glutaraldehydecrosslinked chitosan matrix,and the formation of the passivation layer was alleviated by reducing the contact between zero-valent iron *** average pore diameter of mZVI/GCS was 8.775 nm,which confirmed the mesoporous characteristic of this *** of batch experiments demonstrated that mZVI/GCS exhibited high Cr(Ⅵ)removal efficiency in a wide range of pH(2-10)and temperature(5-35℃).Common groundwater coexisting ions slightly affected m ZVI/*** material showed great reusability,and the average Cr(Ⅵ)removal efficiency was 90.41%during eight *** this study,we also conducted kinetics and isotherms ***-second-order model was the most matched kinetics *** Cr(Ⅵ)adsorption process was fitted by both Langmuir and Freundlich isotherms models,and the maximum Langmuir adsorption capacity of m ZVI/GCS reached243.63 mg/g,which is higher than the adsorption capacities of materials reported in most of the previous ***,the column capacity for Cr(Ⅵ)removal of a mZVI/GCS-packed column was 6.4 times higher than that of a mZVI-packed column in a 50-day ***,mZVI/GCS with a porous structure effectively relieved passivation problems of mZVI and showed practical application prospects as groundwater Cr(Ⅵ)remediation material with practical application prospects.

关键词： Chitosan Glutaraldehyde mZVI Cr(Ⅵ) Groundwater

Localization−delocalization transitions in non-Hermitian Aharonov−Bohm cages

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Frontiers of physics 2024年第3期19卷 39-50页

作者： xiang Li Jin liu Tao liu School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

A unique feature of non-Hermitian systems is the extreme sensitivity of the eigenspectrum to boundary conditions with the emergence of the non-Hermitian skin effect (NHSE). A NHSE originates from the point-gap topology of complex eigenspectrum, where an extensive number of eigenstates are anomalously localized at the boundary driven by nonreciprocal dissipation. Two different approaches to create localization are disorder and flat-band spectrum, and their interplay can lead to the anomalous inverse Anderson localization, where the Bernoulli anti-symmetric disorder induces mobility in a full-flat band system in the presence of Aharonov−Bohm (AB) Cage. In this work, we study the localization−delocalization transitions due to the interplay of the point-gap topology, flat band and correlated disorder in the one-dimensional rhombic lattice, where both its Hermitian and non-Hermitian structures show AB cage in the presence of magnetic flux. Although it remains the coexistence of localization and delocalization for the Hermitian rhombic lattice in the presence of the random anti-symmetric disorder, it surprisingly becomes complete delocalization, accompanied by the emergence of NHSE. To further study the effects from the Bernoulli anti-symmetric disorder, we found the similar NHSE due to the interplay of the point-gap topology, correlated disorder and flat bands. Our anomalous localization−delocalization property can be experimentally tested in the classical physical platform, such as electrical circuit.

关键词： non-Hermitian skin effects disorder flat band localization−delocalization transition

A quadrivalent norovirus vaccine based on a chimpanzee adenovirus vector induces potent immunity in mice

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Virologica Sinica 2024年第4期39卷 675-684页

作者： Yihua Jiang Lingjin Sun Nan Qiao xiang Wang Caihong Zhu man Xing Hui liu Ping Zhou Dongming Zhou Department of Pathogen Biology School of Basic Medical SciencesTianjin Medical UniversityTianjin300070China Shanghai Public Health Clinical Center Fudan UniversityShanghai201508China R&D Centre Chengdu Kanghua Biological Products Co.LtdChengdu610000China Institut Pasteur of Shanghai Chinese Academy of SciencesShanghai200031China

Norovirus(NoV)infection is a major cause of gastroenteritis *** virus poses great challenges in developing vaccines with broad immune protection due to its genetic and antigenic *** date,there are no approved NoV vaccines for clinical ***,we aimed to develop a broad-acting quadrivalent NoV vaccine based on a chimpanzee adenovirus vector,AdC68,carrying the major capsid protein(VP1)of noroviral GI and GII *** to intramuscular(i.m.),intranasal(i.n.),or other prime-boost immunization regimens(i.m.t i.m.,i.m.t i.n.,i.n.t i.m.),AdC68-GI.1-GII.3(E1)-GII.4-GII.17(E3),administered via i.n.t *** higher titers of serum IgG antibodies and higher IgA antibodies in bronchoalveolar lavage fluid(BALF)and saliva against the four homologous VP1s in *** also significantly stimulated the production of blocking antibodies against the four *** response to re-stimulation with virus-like particles(VLP)-GI.1,VLP-GII.3,VLP-GII.4,and VLP-GII.17,the quadrivalent vaccine administered according to the i.n.t *** effectively triggered specific cell-mediated immune responses,primarily characterized by IFN-γ***,the preparation of this novel quadrivalent NoV vaccine requires only a single recombinant adenovirus to provide broad preventive immunity against the major GI/GII epidemic strains,making it a promising vaccine candidate for further development.

关键词： Norovirus(NoV) Quadrivalent vaccine Adenovirus vector

An integrative mathematical model of microwave ion thruster for mHz-frequency thrust noise analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 121-136页

作者： xiang NIU Hui liu Daren YU Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

many high-precision space missions need thrusters to produce thrust with low noise to compensate for disturbances and ensure satellite platform stability. Microwave ion thruster is characterized with a wide thrust range and potential for these missions. A cost-effective and accurate mathematical model is crucial for mHz-frequency thrust noise analysis and feedback controller design. The Particle-In-Cell(PIC) and global models are two common simulation tools. The PIC model is characterized with high accuracy but huge computation cost, which is difficult to analyze long-time performance characteristics. Now, the global model is only used for the discharge chamber with low accuracy and cannot reflect ion extraction properties. In this paper, an integrative mathematical model is built for a 1-cm microwave ion thruster and can reflect ion beamlet divergence and impingement on the Accelerator Grid(AG). Simulation results show good agreement with experiments at 0.06 sccm. However, the model demonstrates worse consistency with experiments when the flux increases to 0.1 sccm, which may be because the influence of neutral gas on the Electron Cyclotron Resonance(ECR) is not considered in the model. A long-time(1000 s) simulation is conducted with this model under 35 μN. It takes 3 hrs, and the thrust noise reaches 1 μN/Hz^(0.5) at 1 mHz.

关键词： Electric propulsion Microwave ion thruster Integrative model Sheath property Ion beamlet divergence Thrust noise Plasma

High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： man Zhang Xiao-Xu liu Tian-Yi Ji Yang Li Da-Wei Sheng Shao-Dong Li Pei-Pei Ren Ze-xiang Shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries

Mg/MgO interfaces as efficient hydrogen evolution cathodes causing accelerated corrosion of additive manufactured Mg alloys:A DFT analysis

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Journal of Magnesium and Alloys 2024年第1期12卷 110-119页

作者： man-Fai Ng Kai xiang Kuah Teck Leong Tan Daniel John Blackwood Department of Materials Science&Engineering National University of Singapore9 Engineering Drive 1Singapore 117575Republic of Singapore Institute of High Performance Computing(IHPC) Agency for ScienceTechnology and Research(A∗STAR)1 Fusionopolis Way#16-16 ConnexisSingapore 138632Republic of Singapore

The corrosion rates of additive-manufactured Mg alloys are higher than their as-cast counterparts,possibly due to increased kinetics for the hydrogen evolution reaction on secondary phases,which may include oxide *** Kelvin Probe Force Microscopy demonstrated that MgO inclusions could act as cathodes for Mg corrosion,but their low conductivity likely precludes ***,the density of state calculations through density functional theory using hybrid HSE06 functional revealed overlapping electronic states at the Mg/MgO interface,which facilitates electron transfers and participates in redox *** determination of the hydrogen absorption energy at the Mg/MgO interface reveals it to be an excellent catalytic site,with HER being found to be a factor of 23x more efficient at the interface than on metallic *** results not only support the plausibility of the Mg/MgO interface being an effective cathode to the adjacent anodic Mg matrix during corrosion but also contribute to the understanding of the enhanced cathodic activities observed during the anodic dissolution of magnesium.

关键词： Magnesium Magnesium oxide Interface Hydrogen evolution DFT