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Research in Astronomy and Astrophysics 2024年第6期24卷 227-235页

作者： Xue-Feng Lu Li-Ming Song Ming-Yu Ge Shuang-Nan Zhang Jin-Lu Qu ce cai Cong-Zhan Liu Cheng-Kui Li Yu-Cong Fu Ying-Chen Xu Key Laboratory of Particle Astrophysics Institute of High Energy Physics University of Chinese Academy of Sciences Chinese Academy of Sciences College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Department of Astronomy Beijing Normal University

In October 2022, the magnetar SGR J1935+2154 entered the active outburst state. During the episode, the InsightHXMT satellite carried out a long observation that lasted for 20 days. More than 300 bursts were detected, and a certain amount of persistent radiation signals were also accumulated. This paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT data. At the same time, the burst phase distribution characteristics, spectral lag results of burst, the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are reported. We found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+2154. The observed zero-lag burst does not have a unique spectrum. The time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the burst. We also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile.

关键词： dense matter magnetic fields radiation mechanisms: general

Observation of spectral lines in the exceptional GRB 221009A

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Science China(Physics,Mechanics & Astronomy) 2024年第8期Mechanics & Astronomy) .卷 191-210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 Sciences University of Chinese Academy of Sciences Yunnan Observatories Chinese Academy of Sciences center for Astronomical Mega-Science Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of celestial Objects Chinese Academy of Sciences College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal University College of Electronic and Information Engineering Tongji University

As the brightest gamma-ray burst ever observed, GRB 221009A provided a precious opportunity to explore spectral line features. In 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 lines. For 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 intervals. The central energy of the Gaussian emission line evolves from about 37 to 6 MeV, with a nearly constant ratio（about 10%） between the line width and central energy. Particularly, 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, respectively. We suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V line. We 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 jet. In 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 emission. Interestingly, we find that the flux of the annihilation line in the co-moving frame keeps constant. These 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

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基于深度学习的轮胎压印字符检测与识别

合肥工业大学学报（自然科学版） 2024年第5期47卷 635-641,702页

作者：蔡策秦训鹏常艳昌彭浩武汉理工大学现代汽车零部件技术湖北省重点实验室湖北武汉430070 武汉理工大学湖北省新能源与智能网联车工程技术研究中心湖北武汉430070

在自动化装配线上轮胎与轮毂装配时,需要检测与识别轮胎表面的压印字符串,从而得到轮胎的品牌、型号、尺寸以及生产的年周号等信息,用以管理轮胎信息以及监控轮胎的流向。针对轮胎表面压印字符串的检测与识别问题,文章提出一种基于深度... 详细信息

在自动化装配线上轮胎与轮毂装配时,需要检测与识别轮胎表面的压印字符串,从而得到轮胎的品牌、型号、尺寸以及生产的年周号等信息,用以管理轮胎信息以及监控轮胎的流向。针对轮胎表面压印字符串的检测与识别问题,文章提出一种基于深度学习的轮胎胎面关键字符的检测与识别方法,搭建了可编程逻辑控制器(programmable logic controller,PLC)、工控机和工业相机的自动化检测与识别平台,通过霍夫变换及坐标变换对采集后的图像进行预处理,采用改进的更快速的区域卷积神经网络(faster region-based convolutional neural network,Faster RCNN)算法为基础检测出目标字符串位置,再通过卷积递归神经网络(convolutional recurrent neural network,CRNN)对检测出的目标字符串进行识别,同时利用编码规则校验识别结果,以提升识别结果的准确率。实验结果表明,改进后的算法在进行轮胎压印字符串的检测与识别时其准确率超过97.0%,满足工业生产应用需求。

关键词：压印字符图像处理字符检测字符识别深度学习

Burst Phase Distribution of SGR J1935+2154 Based on Insight-HXMT

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Research in Astronomy and Astrophysics 2023年第3期23卷 68-74页

作者： Xue-Feng Lu Li-Ming Song Ming-Yu Ge You-Li Tuo Shuang-Nan Zhang Jin-Lu Qu ce cai Sheng-Lun Xie Cong-Zhan Liu Cheng-Kui Li Yu-Cong Fu Ying-Chen Xu Tian-Ming Li Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Institute of Astrophysics Central China Normal UniversityWuhan 430079China

On 2020 April 27,the soft gamma-ray repeater SGR J1935+2154 entered its intense outburst episode again.Insight-HXMT carried out about one month observation of the source.A total number of 75 bursts were detected during this activity episode by Insight-HXMT,and persistent emission data were also accumulated.We report on the spin period search result and the phase distribution of burst start times and burst photon arrival times of the Insight-HXMT high energy detectors and Fermi/Gamma-ray Burst Monitor(GBM).We find that the distribution of burst start times is uniform within its spin phase for both Insight-HXMT and Fermi/GBM observations,whereas the phase distribution of burst photons is related to the type of a burst’s energy spectrum.The bursts with the same spectrum have different distribution characteristics in the initial and decay episodes for the activity of magnetar SGR J1935+2154.

关键词： spectrum Fermi distribution

Paired quasi-periodic pulsations of hard X-ray emission in a solar flare

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Science China(Physics,Mechanics & Astronomy) 2023年第5期66卷 195-206页

作者： Hai-Sheng Zhao Dong Li Shao-Lin Xiong Yan-Qiu Zhang Yang Su Wei Chen Yi Zhao Xiao-Bo Li Jia-Cong Liu Wen-Xi Peng Rui Qiao Xin-Qiao Li Xiang-Yang Wen Li-Ming Song Shi-Jie Zheng Xin-Ying Song Xiao-Yun Zhao Yue Huang Shuang-Nan Zhang Shuo Xiao ce cai Zheng-Hua An Can Chen Gang Chen Wei Chen Yan-Qi Du Min Gao Ke Gong Dong-Ya Guo Zhi-Wei Guo Jian-Jian He Bin Li Chao Li Chao-Yang Li Gang Li Jian-Hui Li Lu Li Qing-Xin Li Yan-Guo Li Jing Liang Xiao-Hua Liang Jin-Yuan Liao Xiao-Jing Liu Ya-Qing Liu Qi Luo Xiang Ma Bin Meng Ge Ou Dong-Li Shi Jing-Yan Shi Gong-Xing Sun Xi-Lei Sun You-Li Tuo Chen-Wei Wang Hui Wang Jin Wang Jin-Zhou Wang Ping Wang Wen-Shuai Wang Hong Wu Sheng-Lun Xie Yan-Bing Xu Yu-Peng Xu Wang-Chen Xue Sheng Yang Min Yao Jian-Ying Ye Qi-Bin Yi Chao-Yue Zhang Da-Li Zhang Fan Zhang Fei Zhang Hong-Mei Zhang Kai Zhang Peng Zhang Xiao-Lu Zhang Zhen Zhang Guo-Ying Zhao Shi-Yi Zhao Chao Zheng Xing Zhou Yue Zhu Key Laboratory for Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China University of Chinese Academy of Sciences Beijing 100049China Department of Astronomy Beijing Normal UniversityBeijing 100875China School of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China Physics and Space Science College China West Normal UniversityNanchong 637002China Key Laboratory of Stellar and Interstellar Physics and Department of Physics Xiangtan UniversityXiangtan 411105China Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Changchun University of Science and TechnologyChangchun 130022China College of Physics and Engineering Qufu Normal UniversityQufu 273165China College of Physics Sciences&Technology Hebei UniversityBaoding 071002China

We investigate high time resolution data obtained by the Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)during the flare event on 2022 April 21 at 01:52 UT.Several subpeaks with durations of 4-6 s have been detected in the hard X-ray precursor phase,and the key feature is that they appear in pairs and seem like double-peak struc-tures.These subpeaks are rarely observed in hard X-ray band and confirmed by the microwave obtained by Nobeyama Radio Polarimeters(NoRP)and Radio Solar Telescope Network(RSTN).While an exponential function can describe the continuum component of the time profile from the precursor to part of the impulsive phase.The periods of quasi-periodic pulsations(QPPs)are detected to be about 7.3 and 12.8 s for the precursor and impulsive phase,respectively,with at least 95%confidence level.The paired QPPs are assumed to be double-peak QPPs and then the scenario of current loop coalescence model is found to be in good agreement with our observation.The precursor phase can be interpreted as the oscillating coalescence of two islands,while the impulsive phase can be interpreted as more islands to coalesce one by one to form larger islands.

关键词： solar flare QPPs loop coalescence circular-ribbon flare

Microstructure and impact behavior of Mg-4Al-5RE-xGd cast magnesium alloys

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Journal of Magnesium and Alloys 2024年第5期12卷 1799-1814页

作者： Jie Wei Qudong Wang Huisheng cai Mahmoud Ebrahimi Chuan Lei National Engineering Research center of Light Alloy Net Forming and Key State Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University

This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd（RE represents La-ce mischmetal; x = 0, 0.2,0.7 wt.%） alloys cast by high-pressure die casting（HPDC）, permanent mold casting（PMC）, and sand casting（SC） techniques. The results indicated that with increasing Gd content, the grain sizes of the HPDC alloy had a slight change, but the grains of the PMC and SC alloys were significantly refined. Besides, the acicular Al11RE3phase was modified into the short-rod shape under the three casting conditions. The impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack initiation. With increasing Gd content,the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack initiation. The impact stress was higher than the tensile stress, exhibiting a strain rate sensitivity for the mechanical response; however, the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing strain. Abundant dimples covered the fracture surface of the fine-grained HPDC alloys, indicating a typical ductile fracture. Nevertheless, due to the deficient {■} twinning activity and the suppressed grain boundary sliding during the impact event, the HPDC alloys showed insufficient plastic deformation capacity.

关键词： Mg-Al-RE alloy Gadolinium Microstructure Impact behavior

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不规则Y形铝型材多点拉弯成形截面变形分析

吉林大学学报（工学版） 2024年第1期54卷 105-113页

作者：李义吕晨阳梁继才梁策吉林大学材料科学与工程学院长春130022 吉林大学汽车材料教育部重点实验室长春130022 吉林大学重庆研究院重庆401123

为了提高型材多点拉弯成形后的成形质量,基于ABAQUS有限元模拟了不规则Y形铝型材多点拉弯成形中截面变形规律。首先,通过控制变量法探究了不同工艺参数(模具数、弯曲半径、预拉伸量、补拉伸量和摩擦因数)对制件截面变形分布的影响规律... 详细信息

为了提高型材多点拉弯成形后的成形质量,基于ABAQUS有限元模拟了不规则Y形铝型材多点拉弯成形中截面变形规律。首先,通过控制变量法探究了不同工艺参数(模具数、弯曲半径、预拉伸量、补拉伸量和摩擦因数)对制件截面变形分布的影响规律。其次,为了综合考虑各工艺参数间的相互作用,结合正交试验分析进一步探究了各工艺参数对制件最大截面变形的影响程度。结果显示,补拉伸量变化时,截面宽度变形最大值为1.58 mm,最小值为1.06mm,其变化幅度为49.1%;截面高度变形最大值为1.25mm,最小值为0.77 mm,其变化幅度为62.3%,即补拉伸量对截面变形的影响最大。最后,综合分析后确定多点拉弯最优成形方案,并通过模拟和试验验证了该成形方案的可行性,从而极大地提高制件的成形质量。

关键词：多点拉弯截面变形控制变量法工艺参数正交试验

Codelivery of anti-CD47 antibody and chlorin e6 using a dual pH-sensitive nanodrug for photodynamic immunotherapy of osteosarcoma

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Oncology Research 2024年第4期32卷 691-702页

作者： JIJIE XIAO HONG XIAO YUJUN cai JIANWEI LIAO JUE LIU LIN YAO SHAOLIN LI Department of Radiology The Fifth Affiliated Hospital of Sun Yat-Sen UniversityZhuhai510900China Department of Ultrasound The Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou528405China PCFM Lab of Ministry of Education School of Materials Science and EngineeringGuangzhou510275China

Osteosarcoma is a malignant tumor originating from bone tissue that progresses rapidly and has a poor patient prognosis.Immunotherapy has shown great potential in the treatment of osteosarcoma.However,the immunosuppressive microenvironment severely limits the efficacy of osteosarcoma treatment.The dual pH-sensitive nanocarrier has emerged as an effective antitumor drug delivery system that can selectively release drugs into the acidic tumor microenvironment.Here,we prepared a dual pH-sensitive nanocarrier,loaded with the photosensitizer Chlorin e6(ce6)and CD47 monoclonal antibodies(aCD47),to deliver synergistic photodynamic and immunotherapy of osteosarcoma.On laser irradiation,ce6 can generate reactive oxygen species(ROS)to kill cancer cells directly and induces immunogenic tumor cell death(ICD),which further facilitates the dendritic cell maturation induced by blockade of CD47 by aCD47.Moreover,both calreticulin released during ICD and CD47 blockade can accelerate phagocytosis of tumor cells by macrophages,promote antigen presentation,and eventually induce T lymphocyte-mediated antitumor immunity.Overall,the dual pH-sensitive nanodrug loaded with ce6 and aCD47 showed excellent immune-activating and anti-tumor effects in osteosarcoma,which may lay the theoretical foundation for a novel combination model of osteosarcoma treatment.

关键词： Immunotherapy Osteosarcoma Nanodrug Photodynamic therapy CD47

Effects of arbuscular mycorrhizal fungi on zinc uptake,translocation and accumulation in winter wheat during whole plant growth stages

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Pedosphere 2024年第2期34卷 374-384页

作者： Jing YANG Chuangye ZHANG Yifan LIU Yuanzhe MA Xiangyao WU Jun cai Fuyong WU College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and Agricultural Environment of Northwest of Ministry of Agriculture Yangling 712100China

Although arbuscular mycorrhizal fungi(AMF)could play important roles in zinc(Zn)uptake in host plants,the effects of AMF on Zn uptake and transport in winter wheat during the whole growth stages remain unclear.A pot experiment was conducted to investigate the effects of Funneliformis mosseae(Fm)and Claroideoglomus etunicatum(ce)on Zn absorption,transport,and accumulation in winter wheat growing in soils spiked with different Zn levels(0,2.5,and 25 mg kg^(-1)).The results showed that there was a significant correlation between mycorrhizal colonization rate and Zn absorption efficiency in winter wheat roots during the post-anthesis period,but there was no significant correlation during the pre-anthesis period.Arbuscular mycorrhizal fungi significantly increased Zn concentrations(0.56–1.58 times)in wheat grains under 0 mg kg^(-1)Zn level,but decreased Zn concentrations in wheat grains under 25 mg kg^(-1)Zn level.Additionally,at the filling and maturity stages,AMF increased Zn absorption rate and the contribution of root Zn uptake to grain Zn by 3–14 and 0.36–0.64 times,respectively,under 0 mg kg^(-1)Zn level and 0.21–1.02 and 0.27–0.37 times,respectively,under 2.5 mg kg^(-1)Zn level.However,AMF decreased root Zn absorption rate(0.32–0.61 times)and increased the contribution of Zn remobilization in vegetative tissues to grain Zn(1.69–2.01 times)under 25 mg kg^(-1)Zn level.This study would complement the mechanisms and effects of AMF on Zn absorption and transport in winter wheat and provide a potential method for the application of AMF to enrich wheat grain Zn.

关键词： grain Zn source mycorrhizal response post-anthesis period Zn absorption rate Zn remobilization

Epidemiology of mental health comorbidity in patients with atopic dermatitis:An analysis of trends from 1998 to 2022

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Epidemiology of mental health comorbidity in patients with a...