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Shock Response in Cage-like Polynitrocubane High-Energy-Density Materials: Competition between Strain Energy and Structural Symmetry

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Energetic Materials Frontiers 2025年

作者： Qing-guan Song Li Meng Sheng-li Jiang Lei Zhang Ze-yao Mo Institute of Applied Physics and Computational Mathematics Beijing 100088 China CAEP Software Center for High Performance Numerical Simulation Beijing 100088 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang 621999 China School of Materials Science & Engineering Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of Technology Beijing 100081 China

The cage-like structures provide a unique combination of strain energy for enhanced energy storage and hyperstatic constraints to stabilize the system, positioning them as promising pioneers in advancing high-energy-density materials (HEDMs). However, the shock response of cage-like HEDMs is highly complex and exhibits significant variability, posing a grand challenge in the underlying mechanisms. This study reveals that the shock response of cage-like HEDMs is regulated by the interplay between strain energy and structural symmetry, and introduces a physical model to quantitatively describe how they determine shock stability. The investigated systems include a comprehensive series of cage-like polynitrocubane HEDMs, with each carbon atom in the backbone progressively functionalized with nitro groups. Ab initio molecular dynamics (AIMD) simulations were employed to simulate dynamic and kinetic responses at shock velocities ranging from 8 km·s -1 to 11 km·s -1 , with validation provided by consistent Hugoniot curves that align with reported experimental data. Nitro groups at the carbon-based cage structure, recognized as explosion functional groups, were found to substantially increase the system's strain energy. However, an increasing number of nitro groups also intensified electrostatic repulsion among oxygen lone pairs, which weakens structural integrity and renders the material more susceptible to disassembly under shock conditions. Conversely, structural symmetry—including both the cage-like molecular conformation and spatial packing within the crystal lattice—was found to mitigate these destabilizing effects, effectively balancing the trade-off between energy storage and structural stability. Based on these findings, we propose a physical model that captures the essential factors driving shock initiation in cage-like polynitrocubane HEDMs, offering new insights to inform the design and application of novel advanced HEDMs.

关键词： shock stability cage-like high-energy-density materials strain energy structural symmetry strain tensor

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A Direct Position Determination Method for Four-station TDOA Location System

A Direct Position Determination Method for Four-station TDOA...

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Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Sun-Rui Qi Chen-Shun Yuan Bai-Jin Liang Gao-Lu Li-Hu Sun-Heng BEIJING INSTITUTE OF SPACE LONG MARCH VEHICLE National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

Aiming at the four-station networked TDOA (Time Difference of Arrival) localization system, a direct location method based on electronic elevation map search is proposed, the Geometric Dilution Precision (GDOP) is derived, and the factors affecting the location accuracy are analyzed. The location method under real conditions is also simulated, and its feasibility is demonstrated, which provides a new engineering method for networked TDOA location.

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An Improved Adaptive Pulse Compression Algorithm Based on Linear Frequency Modulation Signal

An Improved Adaptive Pulse Compression Algorithm Based on Li...

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Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Jinliang Bai Peng Qin Hu Li Ran Zhang Xinyu Zhang National key laboratory of science and technology on test physics and numerical mathematics Beijing Institute of Space Long March Vehicle Beijing China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

In this paper, the radar signal is optimized based on the pulse compression repair (PCR) algorithm, which mainly reduces the computational amount to makes it more advantageous to achieve. The main idea is to implement PCR in a parallel way. The method of implementing parallelism is well known, that is, the signal is segmented, and different segmentation methods can be adopted according to different signal models. In this paper, the chirp signal is mainly processed by decimation and segmentation, and some intrinsic benefits of the performance and computational balance of the proposed method are discussed.

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Broadband Dual-Polarized Antenna with Enhanced Front-To-Back Ratio Using Meta-surface

Broadband Dual-Polarized Antenna with Enhanced Front-To-Back...

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Asia-Pacific Conference on Microwave

作者： Pei Zheng Yuwei Qiu Jinliang Bai Ziwei Xu Xin Liu Jiaqi Liu Jun Li Shuo Zhang Hailiang Zhu Gao Wei National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China Northwestern Polytechnical University Xi'an Shaanxi China

ISBN: (数字)9781728135175

ISBN: (纸本)9781728135182

A novel broadband dual-polarized dipole antenna with enhanced front-to-back ratio is proposed. By placing metasurface around the radiators, the proposed dipole antenna exhibits wide impedance bandwidth (S11&S22 ≤ -12dB) of 52% from 0.675 to 1.15 GHz, covering the lower frequency band (0.69~0.96GHz) of base station antenna. Simulated results show that the front-to-back ratio can be increased by 4-5dB after adding the meta-surface, radiation pattern with enhanced frontto-back ratio (FBR) higher than 20dB were achieved over the operating frequency range. In addition, the antenna architecture is simple and easy to fabricate in base stations that can be used in modern mobile communication systems.

关键词： Dipole antennas Broadband antennas Antenna radiation patterns Probes Broadband communication Bandwidth

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Physical Layer Security of Cooperative Network with Machine Learning-based Relay Selection

Physical Layer Security of Cooperative Network with Machine ...

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IEEE International Symposium on Electromagnetic Compatibility (EMC-Beijing)

作者： Fang Liu Yajuan Wang Hu Li Beijing University of Posts and Telecommunications Beijing China National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics Beijing China

ISBN: (数字)9781728144160

ISBN: (纸本)9781728144177

We explore the potential of machine learning for relay selection in a cooperative multi-relay wiretap network with decode-and-forward (DF) protocol, aiming to enhance the physical layer security. Such network is divided into two scenarios according to whether the channel state information (CSI) of wiretap links is available or not for source, when it is assumed that the CSI of the main links has been known at the source. In addition, two machine learning-based schemes, namely, the convolutional neural network(CNN)-based multi-classifier and the support vector machine(SVM)-based multi-classifier, are proposed to characterize the conventional optimization problem of cooperative relay selection as a multi-classification problem in two scenarios mentioned above. In our study, we provide more insight into the spatial correlation of CSI and make the first attempt to introduce the CNN for relay selection in a cooperative multi-relay wiretap network. Finally, the simulation results indicate that two machine learning-based with relatively low selection complexity and less feedback amount achieve substantially the same secrecy performance as the conventional selection scheme.

关键词： Relays Training Machine learning Support vector machines Physical layer security Neurons Correlation

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Impact analysis of CFAR detection for false targets generated by the phase-switched screen

Impact analysis of CFAR detection for false targets generate...

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Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Ran Zhang Yuan S Chen Yu X Zhang Lei Guo Liang J Bai Ping L Zhang National key laboratory of science and technology on test physics and numerical mathematics Beijing institute of Space Long March Vehicle No. 1 Nanda Hongmen Road of Fengtai District Beijing China National key laboratory of science and technology on test physics and numerical mathematics Beijing institute of Space Long March Vehicle Beijing China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

The phase-switched screen (PSS) has been proved effective in the application of shielding a target or deceiving the radar system when the modulation frequency of it is set greater or smaller than the signal bandwidth. This paper analyses impacts of false targets generated by PSS (PSS-decoys) echoes on radar constant false alarm rate detection. The generation principle of PSS-decoys and the key factors that influence the signatures of PSS-decoys are introduced briefly at first. On base of it, the detection cost caused by the false alarm and false dismissal in a search period of radar is chosen as the criteria of detection performance. The detection costs of CA-CFAR, OS-CFAR, CMLD-CFAR detectors under multiple decoys jamming environment are analysed. Specially, we investigate the influence of the PSS key factors on detection costs from the perspective of simulation. The results show that detection costs will increase remarkably due to false targets existing and it is sensitive to the switching frequency, and the relationship to the duty ratio is tightly relevant to SNR. Among three detectors, the detection costs of CMLD-CFAR detector are higher than that of adopting CA-CFAR and that of adopting OS-CFAR.

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Pathways of Influence of the Northern Hemisphere Mid–high Latitudes on East Asian Climate: A Review

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Advances in Atmospheric sciences 2019年第9期36卷 902-921页

作者： Jianping LI Fei ZHENG Cheng SUN Juan FENG Jing WANG Key Laboratory of Physical Oceanography–Institute for Advanced Ocean Studies Ocean University of China and Qingdao National Laboratory for Marine Science and TechnologyQingdao 266003China College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

This paper reviews recent progress made by Chinese scientists on the pathways of influence of the Northern Hemisphere mid-high latitudes on East Asian climate within the framework of a“coupled oceanic-atmospheric(land-atmospheric or seaice-atmospheric)bridge”and“chain coupled bridge”.Four major categories of pathways are concentrated upon,as follows:Pathway A—from North Atlantic to East Asia;Pathway B—from the North Pacific to East Asia;Pathway C—from the Arctic to East Asia;and Pathway D—the synergistic effects of the mid-high latitudes and *** addition,definitions of the terms“combined effect”,“synergistic effect”and“antagonistic effect”of two or more factors of influence or processes and their criteria are introduced,so as to objectively investigate those effects in future research.

关键词： East Asian climate Northern Hemisphere mid-high latitudes coupled oceanic-land-sea-ice-atmospheric bridge chain coupled bridge pathway synergistic effect

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Inclusive-photon production and its dependence on photon isolation in pp collisions at √s = 13 TeV using 139 fb⁻¹ of ATLAS data

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Journal of High Energy physics 2023年第7期2023卷 1-71页

作者： Aad, G. Abbott, B. Abeling, K. Abidi, S.H. Aboulhorma, A. Abramowicz, H. Abreu, H. Abulaiti, Y. Abusleme Hoffman, A.C. Acharya, B.S. Adam Bourdarios, C. Adamczyk, L. Adamek, L. Addepalli, S.V. Adelman, J. Adiguzel, A. Adorni, S. Adye, T. Affolder, A.A. Afik, Y. Agaras, M.N. Agarwala, J. Aggarwal, A. Agheorghiesei, C. Aguilar-Saavedra, J.A. Ahmad, A. Ahmadov, F. Ahmed, W.S. Ahuja, S. Ai, X. Aielli, G. Ait Tamlihat, M. Aitbenchikh, B. Aizenberg, I. Akbiyik, M. Åkesson, T.P.A. Akimov, A.V. Al Khoury, K. Alberghi, G.L. Albert, J. Albicocco, P. Alderweireldt, S. Aleksa, M. Aleksandrov, I.N. Alexa, C. Alexopoulos, T. Alfonsi, A. Alfonsi, F. Alhroob, M. Ali, B. Ali, S. Aliev, M. Alimonti, G. Alkakhi, W. Allaire, C. Allbrooke, B.M.M. Allendes Flores, C.A. Allport, P.P. Aloisio, A. Alonso, F. Alpigiani, C. Alvarez Estevez, M. Alvarez Fernandez, A. Alviggi, M.G. Aly, M. Amaral Coutinho, Y. Ambler, A. Amelung, C. Amerl, M. Ames, C.G. Amidei, D. Amor Dos Santos, S.P. Amos, K.R. Ananiev, V. Anastopoulos, C. Andeen, T. Anders, J.K. Andrean, S.Y. Andreazza, A. Angelidakis, S. Angerami, A. Anisenkov, A.V. Annovi, A. Antel, C. Anthony, M.T. Antipov, E. Antonelli, M. Antrim, D.J.A. Anulli, F. Aoki, M. Aoki, T. Aparisi Pozo, J.A. Aparo, M.A. Aperio Bella, L. Appelt, C. Aranzabal, N. Araujo Ferraz, V. Arcangeletti, C. Arce, A.T.H. Arena, E. Arguin, J.-F. Argyropoulos, S. Arling, J.-H. Armbruster, A.J. Arnaez, O. Arnold, H. Arrubarrena Tame, Z.P. Artoni, G. Asada, H. Asai, K. Asai, S. Asbah, N.A. Assahsah, J. Assamagan, K. Astalos, R. Atkin, R.J. Atkinson, M. Atlay, N.B. Atmani, H. Atmasiddha, P.A. Augsten, K. Auricchio, S. Auriol, A.D. Austrup, V.A. Avner, G. Avolio, G. Axiotis, K. Azuelos, G. Babal, D. Bachacou, H. Bachas, K. Bachiu, A. Backman, F. Badea, A. Bagnaia, P. Bahmani, M. Bailey, A.J. Bailey, V.R. Baines, J.T. Bakalis, C. Baker, O.K. Bakker, P.J. Bakos, E. Bakshi Gupta, D. Balasubramanian, R. Baldin, E.M. Balek, P. Ballabene, E. Balli, F. Baltes, L.M. Balunas, W.K. Balz, J. Banas, E. Bandieramonte, M. Bandyopadhyay, A. Ba Department of Physics University of Adelaide Adelaide Australia Department of Physics University of Alberta Edmonton AB Canada Department of Physics Ankara University Ankara Turkey Division of Physics TOBB University of Economics and Technology Ankara Turkey LAPP Univ. Savoie Mont Blanc CNRS/IN2P3 Annecy France APC Université Paris Cité CNRS/IN2P3 Paris France High Energy Physics Division Argonne National Laboratory Argonne IL United States Department of Physics University of Arizona Tucson AZ United States Department of Physics University of Texas at Arlington Arlington TX United States Physics Department National and Kapodistrian University of Athens Athens Greece Physics Department National Technical University of Athens Zografou Greece Department of Physics University of Texas at Austin Austin TX United States Institute of Physics Azerbaijan Academy of Sciences Baku Azerbaijan Institut de Física d’Altes Energies (IFAE) Barcelona Institute of Science and Technology Barcelona Spain Institute of High Energy Physics Chinese Academy of Sciences Beijing China Physics Department Tsinghua University Beijing China Department of Physics Nanjing University Nanjing China University of Chinese Academy of Science (UCAS) Beijing China Institute of Physics University of Belgrade Belgrade Serbia Department for Physics and Technology University of Bergen Bergen Norway Physics Division Lawrence Berkeley National Laboratory Berkeley CA United States Institut für Physik Humboldt Universität zu Berlin Berlin Germany Albert Einstein Center for Fundamental Physics and Laboratory for High Energy Physics University of Bern Bern Switzerland School of Physics and Astronomy University of Birmingham Birmingham United Kingdom Department of Physics Bogazici University Istanbul Turkey Department of Physics Engineering Gaziantep University Gaziantep Turkey Department of Physics Istanbul University Istanbul Turkey Istinye University Sariyer Istanbul Turk

Measurements of differential cross sections are presented for inclusive isolated-photon production in pp collisions at a centre-of-mass energy of 13 TeV provided by the LHC and using 139 fb⁻¹ of data recorded by the ATLAS experiment. The cross sections are measured as functions of the photon transverse energy in different regions of photon pseudorapidity. The photons are required to be isolated by means of a fixed-cone method with two different cone radii. The dependence of the inclusive-photon production on the photon isolation is investigated by measuring the fiducial cross sections as functions of the isolation-cone radius and the ratios of the differential cross sections with different radii in different regions of photon pseudorapidity. The results presented in this paper constitute an improvement with respect to those published by ATLAS earlier: the measurements are provided for different isolation radii and with a more granular segmentation in photon pseudorapidity that can be exploited in improving the determination of the proton parton distribution functions. These improvements provide a more in-depth test of the theoretical predictions. Next-to-leading-order QCD predictions from JETPHOX and SHERPA and next-to-next-to-leading-order QCD predictions from NNLOJET are compared to the measurements, using several parameterisations of the proton parton distribution functions. The measured cross sections are well described by the fixed-order QCD predictions within the experimental and theoretical uncertainties in most of the investigated phase-space region. [Figure not available: see fulltext.] © 2023, The Author(s).

关键词： Hadron-Hadron Scattering

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Experimental test of High-Dimensional Quantum Contextuality Based on Contextuality Concentration

arXiv

引用

arXiv 2022年

作者： Liu, Zheng-Hao Meng, Hui-Xian Xu, Zhen-Peng Zhou, Jie Chen, Jing-Ling Xu, Jin-Shi Li, Chuan-Feng Guo, Guang-Can Cabello, Adán CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei230026 China CAS Centre For Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei230026 China School of Mathematics and Physics North China Electric Power University Beijing102206 China Theoretical Physics Division Chern Institute of Mathematics Nankai University Tianjin300071 China Naturwissenschaftlich-Technische Fakultät Universität Siegen Walter-Flex-Straße 3 Siegen57068 Germany Centre for Quantum Technologies National University of Singapore 117543 Singapore Hefei National Laboratory University of Science and Technology of China Hefei230088 China Departamento de Física Aplicada II Universidad de Sevilla SevillaE-41012 Spain Instituto Carlos I de Física Teórica y Computacional Universidad de Sevilla SevillaE-41012 Spain

Contextuality is a distinctive feature of quantum theory and a fundamental resource for quantum computation. However, existing examples of contextuality in high-dimensional systems lack the necessary robustness required in experiments. Here we address this problem by identifying a family of noncontextuality inequalities whose maximum quantum violation grows with the dimension of the system. At first glance, this contextuality is the single-system version of multipartite Bell nonlocality taken to an extreme form. What is interesting is that the single-system version achieves the same degree of contextuality but uses a Hilbert space of lower dimension. That is, contextuality "concentrates" as the degree of contextuality per dimension increases. We show the practicality of this result by presenting an experimental test of contextuality in a seven-dimensional system. By simulating sequences of quantum ideal measurements with destructive measurements and repreparation in an all-optical setup, we report a violation of 68.7 standard deviations of the simplest case of the noncontextuality inequalities identified. Our results advance the investigation of high-dimensional contextuality, its connection to the Clifford algebra, and its role in quantum computation. © 2022, CC BY-NC-SA.

关键词： Quantum computers

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Photoinduced anisotropic lattice dynamic response and domain formation in thermoelectric SnSe

arXiv

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arXiv 2021年

作者： Wang, Wei Wu, Lijun Li, Junjie Aryal, Niraj Jin, Xilian Liu, Yu Fedurin, Mikhail Babzien, Marcus Kupfer, Rotem Palmer, Mark Petrovic, Cedomir Yin, Weiguo Dean, Mark P.M. Robinson, Ian Tao, Jing Zhu, Yimei Condensed Matter Physics and Materials Science Division Brookhaven National Laboratory UptonNY11973 United States State Key Laboratory of Superhard Materials College of Physics Jilin University Changchun130012 China Accelerator Science & Technology Initiative Accelerator Test Facility Brookhaven National Laboratory UptonNY11973 United States London Centre for Nanotechnology University College LondonWC1E 6BT United Kingdom

Identifying and understanding the mechanisms behind strong phonon-phonon scattering in condensed matter systems is critical to maximizing the efficiency of thermoelectric devices. To date, the leading method to address this has been to meticulously survey the full phonon dispersion of the material in order to isolate modes with anomalously large linewidth and temperature-dependence. Here we combine quantitative MeV ultrafast electron diffraction (UED) analysis with Monte Carlo based dynamic diffraction simulation and first-principles calculations to directly unveil the soft, anharmonic lattice distortions of model thermoelectric material SnSe. A small single-crystal sample is photoexcited with ultrafast optical pulses and the soft, anharmonic lattice distortions are isolated using MeV-UED as those associated with long relaxation time and large displacements. We reveal that these modes have interlayer shear strain character, induced mainly by c-axis atomic displacements, resulting in domain formation in the transient state. These findings provide an innovative approach to identify mechanisms for ultralow and anisotropic thermal conductivity and a promising route to optimizing thermoelectric devices. © 2021, CC BY.

关键词： Monte Carlo methods

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