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Collapse Velocity and Prompt Explosion for the Presupernova Model Ws15M_⊙

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chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 455-460页

作者： Zhi-quan Luo Men-quan Liu Qiu-He peng Zuo-Heng Xie institute of Theoretical Physics China West Normal University Nanchong 637002 Department of Physics Sichuan University Chengdu 610065 Department of Astronomy Nanjing University Nanjing 210093 institute of Applied Mathematics Chinese Academy of Sciences Beijing 100080

For the presupernova modelWs15M⊙, we re-calculate the electron capture （EC） timescale and hydrodynamical （HD） timescale. We found that the EC timescale can be smaller than the HD timescale in the inner region of the collapse iron core at the moment immediately before the shock wave bounce. The change in these two timescales at the late stage of core collapse is expected to affect the collapse velocity. If the late-time collapse velocity is artificially increased by a small quantity, then prompt explosion of the supernova may happen. Further calculations are still needed to check the plausibility of the acceleration mechanism caused by the faster EC process.

关键词： star: supernova-- nuclear reaction -- nucleosynthesis

A review of surface roughness measurements based on laser speckle method

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Journal of Iron and Steel Research International 2023年第10期30卷 1897-1915页

作者： Mei-qi Shao Dong Xu Si-yi Li Xiao-gang Zuo Chang-ke Chen Gong-zhuang peng Jia-min Zhang Xiao-chen Wang quan Yang institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China Xinjiang Joinworld Co. Ltd.Urumqi 830000XinjiangChina

Surface roughness is commonly used to characterize material microstructure during processing,and accurate measurement of surface roughness is the premise and foundation of ***,online non-destructive measurement of surface roughness based on the laser speckle method has become a hot issue in recent *** improvements in surface roughness measurements based on the laser speckle method are systematically *** of speckle formation is *** statistical properties of the speckle patterns including first-order statistical properties and second-order statistical properties are directly related to surface *** roughness measurements based on the laser speckle method are roughly divided into the speckle contrast method,speckle correlation method,and fractal *** three methods are described in detail,and an extensive comparison among all the methods is *** recent progresses and application of surface roughness measurements are ***,surface roughness measurements based on the laser speckle method are prospected and summarized.

关键词： Surface roughness Non-destructive measurement Laser speckle method Speckle pattern Statistical property

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阴影栅膜层对阴极发射性能的影响

真空电子技术 2024年第4期 47-53页

作者：王卉张珂杨鹏云北京真空电子技术研究所北京100015

研究了栅控行波管中阴影栅抑制发射膜层对阴极电子发射性能的影响。阴影栅和阴极的表面结构及成分分析结果表明,温度越高,时间越长,阴极和阴影栅表面微观结构改变越大,阴极表面活性钡含量越少。阴极表面覆抑制薄膜研究结果表明,铪和钽... 详细信息

研究了栅控行波管中阴影栅抑制发射膜层对阴极电子发射性能的影响。阴影栅和阴极的表面结构及成分分析结果表明,温度越高,时间越长,阴极和阴影栅表面微观结构改变越大,阴极表面活性钡含量越少。阴极表面覆抑制薄膜研究结果表明,铪和钽薄膜对阴极发射抑制作用相当,锆膜的抑制效果最佳。重点研究了锆薄膜不同覆盖面积的阴极发射性能及其抑制发射的机理。

关键词：栅控行波管阴极热丝组件抑制发射金属膜层

The In-Flight Realtime Trigger and Localization Software of GECAM

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Research in Astronomy and Astrophysics 2024年第10期24卷 11-24页

作者： Xiao-Yun Zhao Shao-Lin Xiong Xiang-Yang Wen Xin-Qiao Li Ce Cai Shuo Xiao Qi Luo Wen-Xi peng Dong-Ya Guo Zheng-Hua An ke Gong Jin-Yuan Liao Yan-Qiu Zhang Yue Huang Lu Li Xing Wen Fei Zhang Jing Duan Chen-Wei Wang Dong-Li Shi peng Zhang Qi-Bin Yi Chao-Yang Li Yan-Bing Xu Xiao-Hua Liang Ya-Qing Liu Da-Li Zhang Xi-Lei Sun Fan Zhang Gang Chen Huan-Yu Wang Sheng Yang Xiao-Jing Liu Min Gao Mao-Shun Li Jin-Zhou Wang Xing Zhou Yi Zhao Wang-Chen Xue Chao Zheng Jia-Cong Liu Xing-Bo Han Jin-Ling Qi Jia Huang ke-ke Zhang Can Chen Xiong-Tao Yang Dong-Jie Hou Yu-Sa Wang Rui Qiao Xiang Ma Xiao-Bo Li Ping Wang Xin-Ying Song Li-Ming Song Shi-Jie Zheng Bing Li Hong-Mei Zhang Yue Zhu Wei Chen Jian-Jian He Zhen Zhang Jin Hou Hong-Jun Wang Yan-Chao Hao Xiang-Yu Wang Zong-Yuan Yang Zhi-Long Wen Zhi Chang Yuan-Yuan Du Rui Gao Xiao-Fei Lan Yan-Guo Li Gang Li Xu-Fang Li Fang-Jun Lu Hong Lu Bin Meng Feng Shi Hui Wang Hui-Zhen Wang Yu-peng Xu Jia-Wei Yang Xue-Juan Yang Shuang-Nan Zhang Chao-Yue Zhang Cheng-Mo Zhang Zhi-Cheng Tang Cheng Cheng key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Chinese Academy of SciencesBeijing 100049China School of Information Science and Technology Southwest Jiaotong UniversityChengdu 611756China key Laboratory of Stellar and Interstellar Physics and Department of Physics Xiangtan UniversityXiangtan 411105China Physics and Space Science College China West Normal UniversityNanchong 637002China Department of Astronomy Beijing Normal UniversityBeijing 100875China Innovation academy for Microsatellites of CAS Shanghai 201203China Changchun University of Science and Technology Changchun 130022China chinese academy of sciences South America Center for Astronomy National Astronomical ObservatoriesCASBeijing 100101China

Realtime trigger and localization of bursts are the key functions of GECAM,an all-sky gamma-ray monitor launched on 2020 December *** developed a multifunctional trigger and localization software operating in the CPU of the GECAM Electronic *** onboard software has the following features:high trigger efficiency for real celestial bursts with a suppression of false triggers caused by charged particle bursts and background fluctuation,dedicated localization algorithm optimized for both short and long bursts,and low time latency of the trigger information which is downlinked through the Global Short Message Communication service of the global BeiDou navigation *** paper provides a detailed description of the design and development of the trigger and localization software system for *** covers the general design,workflow,the main functions,and the algorithms used in the *** paper also includes on-ground trigger tests using simulated gamma-ray bursts generated by a dedicated X-ray tube,as well as an overview of the performance for real celestial bursts during its in-orbit operation.

关键词： telescopes instrumentation:detectors methods:observational

“新型电力系统数字化关键技术综述”专辑评述

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电力系统自动化 2024年第6期48卷 1-12页

作者：李鹏刘念胡秦然周全李知艺于浩孙冰严正文福拴薛禹胜智能电网教育部重点实验室(天津大学) 天津市300072 新能源电力系统国家重点实验室(华北电力大学) 北京市102206 东南大学电气工程学院江苏省南京市210096 湖南大学电气与信息工程学院湖南省长沙市410082 浙江大学电气工程学院浙江省杭州市310027 电力传输与功率变换控制教育部重点实验室(上海交通大学) 上海市200240 南瑞集团有限公司(国网电力科学研究院有限公司) 江苏省南京市211106 智能电网保护和运行控制国家重点实验室江苏省南京市211106

数字化是推动新型电力系统发展的重要动力,已成为广受学术界和产业界关注的热点技术。为此,《电力系统自动化》编辑部组织了“新型电力系统数字化关键技术综述”专辑,系统化介绍了新型电力系统数字化基础元件装备、边缘计算技术、通信... 详细信息

数字化是推动新型电力系统发展的重要动力,已成为广受学术界和产业界关注的热点技术。为此,《电力系统自动化》编辑部组织了“新型电力系统数字化关键技术综述”专辑,系统化介绍了新型电力系统数字化基础元件装备、边缘计算技术、通信安全与防护、智能化调度决策等一系列技术成果,代表了本领域最新技术成果和先进经验。文中立足于新型电力系统数字化发展的整体趋势,对专辑论文按研究方向进行了系统性梳理,对其核心成果与观点进行了归纳总结,希望能够完整呈现专辑成果对新型电力系统数字化关键技术体系的支撑作用,为相关技术研究的进一步深化提供参考。

关键词：新型电力系统数字化边缘计算人工智能信息安全信息物理社会系统

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辽宁奉国寺彩绘泥塑木骨架生物病害研究

文物保护与考古科学 2024年第5期36卷 1-7页

作者：柏柯马星霞马琳燕刘东博傅鹏中国林业科学研究院木材工业研究所北京100091 陕西省文物保护研究院陕西西安710075 古建筑木材科学研究与保护国家文物局重点科研基地(中国林业科学研究院木材工业研究所) 北京100091

辽宁义县奉国寺的彩绘泥塑群中多尊泥塑发生倾斜,初步勘察为木骨架糟朽导致。为确认木骨架糟朽原因,经过现场勘察,采集糟朽木骨架木材、进行树种鉴定、微生物分离和甲虫尸体鉴定。结果显示:两彩绘泥塑木骨架样品分别为硬木松(Pinus sp.... 详细信息

辽宁义县奉国寺的彩绘泥塑群中多尊泥塑发生倾斜,初步勘察为木骨架糟朽导致。为确认木骨架糟朽原因,经过现场勘察,采集糟朽木骨架木材、进行树种鉴定、微生物分离和甲虫尸体鉴定。结果显示:两彩绘泥塑木骨架样品分别为硬木松(Pinus sp.)和杨木(Populus sp.);真菌多样性测序结果表明子囊菌门霉菌为优势真菌,从糟朽木材中分离到一株曲霉(Aspergillus sp.),未见其他腐朽菌;虫体经鉴定为鞘翅目象甲科、窃蠹科、皮蠹科和拟步甲科昆虫。辽宁位于木材腐朽危害中等风险区域(D2),分析认为木骨架糟朽的原因主要为窃蠹和象甲科害虫危害导致,根据甲虫的侵染途径和生长特性,推断木骨架木材在应用之初或者维修替换的新木材未进行预处理,没有杀灭虫卵导致虫卵孵化为幼虫,底部被蠹虫幼虫蛀空导致倾斜。经进一步对奉国寺建筑木构件勘察发现部分柱、梁等构件也出现直径3.mm左右蠹虫羽化孔,说明彩绘泥塑所处的古建筑木构也存在类似的虫害。本研究揭示了窃蠹和象科甲虫对彩绘泥塑的破坏影响,说明了彩绘泥塑木骨架与古建筑木构件在加工使用前进行预防性保护的重要性,为彩绘泥塑的生物病害预防和维修工程中木材防虫害预处理提出了建议。

关键词：彩绘泥塑木骨架古建筑木构件生物病害预防性保护

基于CAE-TSNE的成品油管道运行工况识别

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石油科学通报 2024年第1期9卷 148-157页

作者：郑坚钦杜渐梁永图赵伟王昌丁鹏吴全中国石油规划总院北京100083 中国石油大学(北京)机械与储运工程学院北京102249 浙江大学浙江省饮用水安全与输配技术重点实验室杭州310058

成品油管道运行工况变化频繁,难以精准判断管道运行状态,依靠现场人员进行识别监控易造成误判。本文为实现管道运行工况的准确识别,考虑管道的物理空间特性,分析整理各站运行参数(压力、流量、密度);考虑管道运行的时间序列特性,基于SC... 详细信息

成品油管道运行工况变化频繁,难以精准判断管道运行状态,依靠现场人员进行识别监控易造成误判。本文为实现管道运行工况的准确识别,考虑管道的物理空间特性,分析整理各站运行参数(压力、流量、密度);考虑管道运行的时间序列特性,基于SCADA管道数据构造运行数据矩阵,以克服单一时刻的瞬态扰动。针对管道运行数据高维度、非线性的特点,利用卷积自编码器(CAE)强大的特征压缩及重构能力对管道数据做降噪处理;利用T分布邻域嵌入算法(T-SNE)对管道数据做降维聚类处理,最终建立了基于CAE-TSNE的管道运行工况识别模型。以某两条成品油管道为例,对比主流的非线性分类模型(ANN、DT、RF),结果表明基于CAE-TSNE的工况识别模型精度最高,对降噪后的运行数据识别准确率可达到99%以上,可用于指导现场管道的运行管理。

关键词：成品油管道运行工况识别数据矩阵卷积自编码器 T分布邻域嵌入

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Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 187-206页

作者： Yan-Qiu Zhang Shao-Lin Xiong Ji-Rong Mao Shuang-Nan Zhang Wang-Chen Xue Chao Zheng Jia-Cong Liu Zhen Zhang Xi-Lu Wang Ming-Yu Ge Shu-Xu Yi Li-Ming Song Zheng-Hua An Ce Cai Xin-Qiao Li Wen-Xi peng Wen-Jun Tan Chen-Wei Wang Xiang-Yang Wen Yue Wang Shuo Xiao Fan Zhang peng Zhang Shi-Jie Zheng key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100012China key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China College of Physics and Hebei key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China College of Electronic and Information Engineering Tongji UniversityShanghai 201804China

As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line *** this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption *** the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time *** central energy of the Gaussian emission line evolves from about 3. to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central ***,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,*** suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V *** find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the *** this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt ***,we find that the flux of the annihilation line in the co-moving frame keeps *** discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.

关键词： GRB GRB 221009A emission line

基于TD-GC-O-MS及感官评价分析医用级聚氯乙烯树脂气味物质

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石油化工 2024年第8期53卷 1137-1143页

作者：邓莹楠唐毓婧张桦孙姝琦康鹏李可中石化(北京)化工研究院有限公司中国石化医用卫生材料研究与应用重点实验室北京100013 中国石化齐鲁分公司研究院山东淄博255400

采用热脱附-气相色谱-嗅闻-质谱(TD-GC-O-MS)联用技术与感官评价,对医用聚氯乙烯(PVC)树脂中挥发性有机物(VOCs)的气味物质进行了定性定量分析。通过顶空-气相色谱-质谱联用技术进行初步分析,优化了加热温度和时间,以实现VOCs的最佳释... 详细信息

采用热脱附-气相色谱-嗅闻-质谱(TD-GC-O-MS)联用技术与感官评价,对医用聚氯乙烯(PVC)树脂中挥发性有机物(VOCs)的气味物质进行了定性定量分析。通过顶空-气相色谱-质谱联用技术进行初步分析,优化了加热温度和时间,以实现VOCs的最佳释放效果。利用高灵敏度的TD-GC-O-MS选择了极性色谱柱,提高了VOCs的分离和检测效果,成功实现了对低浓度气味物质的定性和定量检测,确定PVC树脂的主要气味源为烷烃类化合物、异辛醇、丙烯酸丁酯、醋酸、苯乙烯和壬醛等,并追溯气味物质的来源,为低气味PVC生产工艺的改进提供指导。通过感官评价确定工艺优化后的PVC树脂气味显著改善。

关键词：医用级聚氯乙烯树脂热脱附-气相色谱-嗅闻-质谱挥发性有机物定性定量分析气味改善