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Temperature influences of the recoil characteristics for aluminum honeycomb buffer in the tether-net launcher

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Defence Technology（防务技术） 2023年第11期29卷 39-54页

作者： Wen-hui Shi Shuai Yue Chun-bo Wu zhou Liu zhi Liu Bei-bei Zhao Zhong-hua Du Guang-fa Gao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Aerospace System Engineering Shanghai Shanghai201109China Xi'an North qinghua Electromechancal Co. LTDXi'an710038China

Fluctuations in outer space's temperature would affect the spacecraft's regular *** paper aims to study the temperature influences of the aluminum honeycomb buffer in the tether-net ***,a buffer structure was designed to attenuate the pyroshock generated by the pyrotechnic ***,the mechanical properties of aluminum honeycomb at different temperatures were obtained through quasi-static compression ***,the internal ballistic responses of the launcher were gained by the closed bomb tests and the equivalent classical interior ballistic ***,the recoil performance of the launcher with aluminum honeycomb buffer at different temperatures was *** is revealed that the aluminum honeycomb crushing force gradually decreases with the temperature *** peak pressure,burning rate coefficient and velocity increase while the peak time decreases with the temperature increase for the interior *** the launcher recoil responses,the average launch recoil decreases if the aluminum honeycomb doesn't enter the dense *** impact acceleration,projectile velocity and displacement increase as the temperature *** paper spotlights the temperature's influence on the recoil characteristics of the aluminum honeycomb buffer,which provides a new idea for buffering technology of pyrotechnic devices in a complex space environment.

关键词： Tether-net launcher Temperature Aluminum honeycomb buffer Interior ballistic responses Launch recoil characteristics

Gasser-Leutwyler Coefficients of Chiral Lagrangian for Pseudoscalar Goldstone Bosons

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Communications in Theoretical Physics 2006年第1X期46卷 101-108页

作者： zhou Li-Juan WU qing PAN Ji-Huan MENG Cheng-Ju MA Wei-Xing LI Xi-Guo Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China Department of Physics Qingdao University Qingdao 266071 China Department of Physics Hechi College Yizhou 546300 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China Institute of Modern Physics the Chinese Academy of Sciences Lanzhou 730000 China

Based on the Dyson-Schwinger equations in raAnbow approximation for quark propagator with an effective gluon propagator, and on the parametrized fully dressed quark propagator proposed by us, the unknown GasserLeutwyler coeiticients of the chiral Lagrangian for pseudoscalar Goldstone bosons, Li, are predicted respectively. The predicted values of Li in the two different ways are not only in reasonable agreement each other but also in agreement with empirical values used widely in literature and the values predicted by many other theoretical models with QCD characteristics. The compatible results of Gasser-Leutwyler coefficients predicted by our parameterized quark propagator, in turn, clearly verify its extensive validity.

关键词： chiral perturbation theory Gasser-Leutwyler coefficient quark propagator Dyson-Schwinger equations

Compression characteristics of saturated re-compacted glacial tills in Tianmo Gully of Tibet, China

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Journal of Mountain Science 2019年第7期16卷 1661-1674页

作者： CHEN Lei-lei zhou Gordon G.D MU qing-yi CUI Kahlil Fredrick SONG Dong-ri Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Department of Civil Engineering Xi'an Jiaotong UniversityXi'an 710049China

Glacial tills are highly compressible soils composed of loosely cemented sandy silt *** role,for instance,as initial filler materials in geo-technical projects along temperate glacier regions warrant a systematic evaluation of their compressive *** such,we carry out a series of onedimensional compression tests on re-compacted glacial till samples obtained from Tianmo Gully,Tibet,with the aims of evaluating their compressive behavior under controlled initial stress *** yield stress was determined from the void ratio versus consolidation pressure(e-log)*** compression and swelling behaviors were observed during the primary and secondary compressions of the consolidation *** the compression curves,a correlation can be found between the consolidation stress and the void *** addition,we find that the compression curves of glacial tills collapse into a single curve when normalized by the compression *** experimental results in this study provide a basic understanding of the compression characteristics of the glacial tills in Tibet,China.

关键词： Glacial till Compression characteristics One-dimensional consolidation tests Consolidation stress Compression curve

Determination of Amino Acids by Ru(bpy)_3^(2+) Cathodic Electrochemiluminescence with High Sensitivity

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Chemical Research in Chinese Universities 2010年第3期26卷 376-379页

作者： zhou Xiao-guang YUAN Bai-qing ZHANG Lei LIU Yang HAN Dong-xue YOU Tian-yan Department of Chemistry and Chemical Engineering College of Science Northeast Forestry University Harbin 150040 P. R. China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changehun 130022 P. R. China College of Chemistry Jilin University Changchun 130021 P. R. China

The unique cathodic electrochemiluminescence（ECL） emission of Ru（bpy）3^2＋（bpy=2,2′-bipyridine） was observed via Nation film at Au electrode[Au/Nafion/Ru（bpy）3^2＋] at about 0.20 V（vs. Ag/AgCl） and applied to the determination of several amino acids without prior derivatization with high sensitivity. The cathodic electrochemiluminescence（ECL） exhibits the detection limits and linear ranges of several amino acids comparable to or better than those of capillary electrophoresis with conventional ECL detection method（at 1.10-1.20 V vs. Ag/AgCl） based on precolumn derivatization. The results suggest that the cathodic ECL is promising for the detection of amino acids in bioanalysis.

关键词： Cathodic electrochemiluminescence Ru(bpy)3^2+ Nation Au electrode

NWC人工甚低频台站信号产生“条缕状”准捕获电子能谱的模拟研究

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物理学报 2024年第20期73卷 286-299页

作者：刘阳希子项正周晨倪彬彬董俊虎胡景乐王建行郭浩智武汉大学电子信息学院武汉430072

遍布全球的人工甚低频台站发射的信号主要用于对潜通信,在夜间,这些信号可以泄漏进磁层与内辐射带中几十至几百keV电子发生回旋共振,从而导致电子沉降.这一过程是导致内辐射带电子损失的重要原因,也是磁层-电离层耦合过程中能量和物质... 详细信息

遍布全球的人工甚低频台站发射的信号主要用于对潜通信,在夜间,这些信号可以泄漏进磁层与内辐射带中几十至几百keV电子发生回旋共振,从而导致电子沉降.这一过程是导致内辐射带电子损失的重要原因,也是磁层-电离层耦合过程中能量和物质输运的重要环节.被台站信号散射的电子呈现出能量随L增加而减小的“条缕状”能谱结构,与台站信号和电子的一阶回旋共振能量曲线相符.低轨卫星可以对“条缕状”能谱结构进行清晰地观测,为研究近地空间波粒相互作用提供了重要契机.本文基于Drift-Diffusion-Source模型,复现了DEMETER卫星于2009年3月19日多个轨道测量的NWC台站信号导致的“条缕状”能谱,量化了NWC台站信号对辐射带电子的散射作用,明晰了NWC台站信号的幅度和传播角,揭示了内辐射带电子漂移过程中的动态变化规律,为开发人工影响辐射带技术提供了重要理论参考.

关键词：地球辐射带波粒相互作用人工甚低频台站信号电子投掷角扩散

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Modulating the optical and electrical properties of MAPbBr_(3) single crystals via voltage regulation engineering and application in memristors

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Light(Science & Applications) 2020年第1期9卷 957-967页

作者： Jun Xing Chen Zhao Yuting Zou Wenchi Kong zhi Yu Yuwei Shan qingfeng Dong Ding zhou Weili Yu Chunlei Guo The Guo Photonics Laboratory State Key Laboratory of Applied OpticsChangchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunChina University of Chinese Academy of Sciences 100049 BeijingChina State Key Laboratory of Supramolecular Structure and Materials Jilin University130012 ChangchunChina State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunChina The Institute of Optics University of RochesterRochesterNY 14627USA

Defect density is one of the most significant characteristics of perovskite single crystals(PSCs)that determines their optical and electrical properties,but few strategies are available to tune this ***,we demonstrate that voltage regulation is an efficient method to tune defect density,as well as the optical and electrical properties of PSCs.A three-step carrier transport model of MAPbBr_(3) PSCs is proposed to explore the defect regulation mechanism and carrier transport dynamics via an applied *** and steady-state photoluminescence measurements subsequently show that the surface defect density,average carrier lifetime,and photoluminescence intensity can be efficiently tuned by the applied *** particular,when the regulation voltage is 20 V(electrical poling intensity is 0.167 Vμm^(−1)),the surface defect density of MAPbBr_(3) PSCs is reduced by 24.27%,the carrier lifetime is prolonged by 32.04%,and the PL intensity is increased by 112.96%.Furthermore,a voltage-regulated MAPbBr_(3) PSC memristor device shows an adjustable multiresistance,weak ion migration effect and greatly enhanced device *** regulation is a promising engineering technique for developing advanced perovskite optoelectronic devices.

关键词： optical electrical defect

嬗变、聚焦与展望:基于CiteSpace的体育教学模式知识图谱分析

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沧州师范学院学报 2024年第1期40卷 103-109页

作者：傅常浩周君华侯秀丽程志伟鲁东大学体育学院山东烟台264025

运用文献计量法和可视化分析法,对2000-2022年我国体育教学模式研究的期刊文献进行分析.结果表明:该领域的发文量分为波动增长、快速拓展、深化成熟3个阶段;核心作者间缺乏合作;研究机构主要为体育类院校和师范类院校;研究热点为高校、... 详细信息

运用文献计量法和可视化分析法,对2000-2022年我国体育教学模式研究的期刊文献进行分析.结果表明:该领域的发文量分为波动增长、快速拓展、深化成熟3个阶段;核心作者间缺乏合作;研究机构主要为体育类院校和师范类院校;研究热点为高校、教学模式、教学改革;研究前沿为课程改革和互联网+.建议:建立和完善我国体育教学模式研究的核心作者和核心机构群;重视核心素养的培养,加强中小学体育教学模式的研究;推动信息技术与体育教学模式的深度融合.

关键词：体育教学教学模式可视化分析文献计量学

基于Fins/UDP通信协议的采煤机远程监控系统研究

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煤炭技术 2024年第7期43卷 258-261页

作者：赵亦辉孙永锋吴振周转会杨青中国矿业大学机电工程学院江苏徐州221116 西安煤矿机械有限公司西安710200

为推进采煤机自动化水平的提升,研究了基于Fins/UDP通信协议的采煤机远程监控系统。详细阐述了Fins/UDP通信协议的报文构成,并构建了适用于煤矿井下采煤机的远程监控系统架构。借助开源的VUE和Flask框架,展开了系统软件的开发。最后,通... 详细信息

为推进采煤机自动化水平的提升,研究了基于Fins/UDP通信协议的采煤机远程监控系统。详细阐述了Fins/UDP通信协议的报文构成,并构建了适用于煤矿井下采煤机的远程监控系统架构。借助开源的VUE和Flask框架,展开了系统软件的开发。最后,通过一系列实验,对系统的数据采集和指令下发等关键功能进行了验证。实验结果表明,所设计的系统可以实现对采煤机的有效远程监控。

关键词： Fins/UDP通信采煤机远程监控系统 VUE 数据库

Secure connectivity analysis in unmanned aerial vehicle networks

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Frontiers of Information Technology & Electronic Engineering 2018年第3期19卷 409-422页

作者： Xin YUAN zhi-yong FENG Wen-jun XU zhi-qing WEI Ren-ping LIU MOE Key Laboratory of Universal Wireless Communications Global Big Data Technologies Centre University of Technology Sydney

The distinctive characteristics of unmanned aerial vehicle networks （UAVNs）, including highly dynamic network topology, high mobility, and open-air wireless environments, may make UAVNs vulnerable to attacks and threats. In this study, we propose a novel trust model for UAVNs that is based on the behavior and mobility pattern of UAV nodes and the characteristics of inter-UAV channels. The proposed trust model consists of four parts： direct trust section, indirect trust section, integrated trust section, and trust update section. Based on the trust model, the concept of a secure link in UAVNs is formulated that exists only when there is both a physical link and a trust link between two UAVs. Moreover, the metrics of both the physical connectivity probability and the secure connectivity probability between two UAVs are adopted to analyze the connectivity of UAVNs. We derive accurate and analytical expressions of both the physical connectivity probability and the secure connectivity probability using stochastic geometry with or without Doppler shift. Extensive simulations show that compared with the physical connection probability with or without malicious attacks, the proposed trust model can guarantee secure communication and reliable connectivity between UAVs and enhance network performance when UAVNs face malicious attacks and other security risks.

关键词： Unmanned aerial vehicle networks(UAVNs) Trust model Secure connectivity Doppler shift