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Chinese Science Bulletin 2009年第14期54卷 2425-2433页

作者： ZHANG XingHua HOU XiMiao JI Chao liming dou ShuoXing WANG PengYe Laboratory of Soft Matter Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

With atomic force microscopy (AFM) we systematically studied the DNA condensations on mica surfaces induced by multivalent cation spermidine. The pattern of the DNA condensates is a flat single layer, with a core in the centre and DNA wrapping around it at high density. We assume this to be a two-dimensional condensation of free coiled DNA onto negatively charged mica surfaces by the multivalent cation. The DNA molecules condense on mica surfaces via a pathway different from the formation of toroids, rods or globules in bulk solutions. We give an explanation to why toroid structures are difficult to be observed by AFM, and further discuss the relationship between DNA condensations in solutions and on mica surfaces. The present work will be helpful for understanding the behaviors of DNA on charged surfaces, which might be significantly different from that in solutions.

关键词： DNA分子表面云母诱导亚精胺原子力显微镜多价阳离子溶液

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半自动不能正常复原故障分析处理

铁路通信信号工程技术 2024年第6期21卷 30-36页

作者：王昱翔窦丽明王淑琴郄佃举尤玉淇王继柱中北大学太原030051 国家能源投资集团有限责任公司神朔铁路分公司朔西站区山西朔州038500 中国铁路太原局集团有限公司大同电务段山西大同037000

通过逻辑分析半自动接车站、发车站到达复原故障现象,确认故障情况下两站控制台显示器表示灯点灯情况,观察故障情况下两站复原电路继电器动作情况,测试故障情况下两站信号机械室分线盘接收、发送电压数值、幅度,观察脉冲信号时间长度,... 详细信息

通过逻辑分析半自动接车站、发车站到达复原故障现象,确认故障情况下两站控制台显示器表示灯点灯情况,观察故障情况下两站复原电路继电器动作情况,测试故障情况下两站信号机械室分线盘接收、发送电压数值、幅度,观察脉冲信号时间长度,进而充分运用信号集中监测回放故障现象,浏览比对故障情况下两站发送、接收负脉冲电压曲线状态、数据、幅度以及脉冲时间曲线状态、长度,达到精准判定故障范围,确认故障点,快速处理故障之目的。

关键词：逻辑分析半自动复原脉冲长度

Einstein Probe discovery of EP240408a:A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong Chen Nanda Rea Arne Rau Zhiming Cai Huaqing Cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang Chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier liming dou Rob Eyles-Ferris Zhou Fan Hua Feng Shaoyu Fu Johan P. U. Fynbo Lluis Galbany Saurabh W. Jha Shuaiqing Jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng Chen Houlei Chen Tianxiang Chen Wei Chen Yehai Chen Yifan Chen Chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai Huang Jia Huo Zhenqing Jia Bowen Jiang Ge Jin Chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu Huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University National Astronomical Observatories Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas Chinese Academy of Sciences South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Universite' Paris Cite' CNRS Astroparticule et Cosmologie Universite' Paris Cite' CEA Paris-Saclay School of Astronomy and Space Sciences IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research University of Chinese Academy of Sciences The University of Tokyo ESA/ESTEC Noordwijk 2201 AZ The Netherlands Department of Astronomy School of Physics Huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics Key Laboratory of Particle Astrophysics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology Hefei School of Astronomy and Space Sciences University of Science and Technology of China Institute of High Energy Physics Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chinese Academy of Science

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 keV,300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 keV,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for4d,followed by a steep decay till becoming undetectable10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词：

A Possible 250s X-Ray Quasi-periodicity in the Fast Blue Optical Transient AT2018cow

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Research in Astronomy and Astrophysics 2022年第12期22卷 299-310页

作者： Wenjie Zhang Xinwen Shu Jin-Hong Chen Luming Sun Rong-Feng Shen Lian Tao Chun Chen Ning Jiang liming dou Ying Qin Xue-Guang Zhang Liang Zhang Jinlu Qu Tinggui Wang Department of Physics Anhui Normal UniversityWuhu 241002China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China Department of Astronomy Guangzhou UniversityGuangzhou 510006China School of Physics and Technology Nanjing Normal UniversityNanjing 210023China

The fast blue optical transients(FBOTs)are a new population of extragalactic transients of unclear physical origin.A variety of mechanisms has been proposed including failed supernova explosion,shock interaction with a dense medium,young magnetar,accretion onto a compact object and stellar tidal disruption event,but none is *** we report the discovery of a possible X-ray quasi-periodicity signal with a period of~250 s(at a significance level of 99.76%)in the brightest FBOT AT2018cow through the analysis of XMM-Newton/PN *** signal is independently detected at the same frequency in the average power density spectrum from data taken from the Swift telescope,with observations covering from 6 to 37 days after the optical discovery,though the significance level is lower(94.26%).This suggests that the quasi-periodic oscillation(QPO)frequency may be stable over at least 1.1×10^(4)*** the~250 s QPO to be a scaled-down analog of that typically seen in stellar mass black holes,a black hole mass of~103–10^(5)solar masses could be *** overall X-ray luminosity evolution could be modeled with a stellar tidal disruption by a black hole of~10^(4)solar masses,providing a viable mechanism to produce *** findings suggest that other bright FBOTs may also harbor intermediate-mass black holes.

关键词： black hole physics X-rays:individual(AT2018cow) X-rays:bursts

对小地老虎具有杀虫毒力的苏云金芽孢杆菌菌株的分离及鉴定

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植物保护 2007年第5期33卷 41-44页

作者：束长龙谷少华窦黎明陆琼张杰张永军赵虎基宋福平中国农业科学院植物保护研究所植物病虫害生物学国家重点实验室北京100094 北京奥瑞金国丰生物技术有限公司北京102206

从我国3种典型植被覆盖的6个地区的土壤样品分离得到了348株苏云金芽孢杆菌菌株,采用杀虫活性测定方法从中获得了32株对小地老虎具有高毒力的菌株。利用PCR-RFLP鉴定体系和SDS-PAGE蛋白分析法,研究了这32株苏云金芽孢杆菌的杀虫晶体蛋... 详细信息

从我国3种典型植被覆盖的6个地区的土壤样品分离得到了348株苏云金芽孢杆菌菌株,采用杀虫活性测定方法从中获得了32株对小地老虎具有高毒力的菌株。利用PCR-RFLP鉴定体系和SDS-PAGE蛋白分析法,研究了这32株苏云金芽孢杆菌的杀虫晶体蛋白基因类型和晶体蛋白表达情况,对小菜蛾、二化螟、棉铃虫的杀虫活性测定也证明了苏云金芽孢杆菌cry基因类型、表达蛋白及杀虫活性间的相关性。

关键词：苏云金芽孢杆菌 PCR-RFLP 小地老虎棉铃虫

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特异小样本工业产品表面缺陷检测方法研究

河南师范大学学报（自然科学版） 2024年第6期52卷 88-96页

作者：郑李明许天赐高浩然李庆华胡晨光窦智金陵科技学院机电工程学院南京211169 河南师范大学计算机与信息工程学院河南新乡453007 莱芜钢铁集团银山型钢铁有限公司济南271104

基于机器视觉的工业产品表面缺陷检测设备和系统大量应用在工业制造领域,目前其难点在于工业检测数据的采集,由于训练样本缺失导致深度学习网络模型无法有效训练.为解决上述问题,首先,提出一种基于不规则掩码的伤痕样本生成算法,改善了... 详细信息

基于机器视觉的工业产品表面缺陷检测设备和系统大量应用在工业制造领域,目前其难点在于工业检测数据的采集,由于训练样本缺失导致深度学习网络模型无法有效训练.为解决上述问题,首先,提出一种基于不规则掩码的伤痕样本生成算法,改善了钢板表面缺陷检测任务中特异小样本数据集正负样本不均衡的情况;然后,在YOLOv8主干网络引入MHSA多头自注意力,提高对钢板表面缺陷的关注度;最后,使用SIoU替换原损失函数,增强网络模型的定位能力,提高检测的准确性.基于热轧钢板表面缺陷检测问题的实验结果表明,该方法能够有效解决特异小样本工业探伤的具体问题.

关键词：深度学习目标检测 YOLOv8 注意力机制数据增强特异小样

Formulation and consideration of World Health Organization international classification of traditional medicine

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Journal of Traditional Chinese Medicine 2020年第1期40卷 157-161页

作者： Xu Wenjie Zhu liming Zu Lianghua Yan Shiyun Zhang Huaiqiong dou Danbo International Education Collage Shanghai University of Traditional Chinese MedicineShanghai 201203China Shuguang Hospital Shanghai University of Traditional Chinese MedicineShanghai 201203China Institute for International Standardization of Traditional Chinese Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China School of Basic Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Municipal Health Commission Shanghai 200125China

In the 11th revision of the International Classification of Diseases(ICD),the World Health Organization included traditional medicine disorders and patterns originated from ancient Chinese medicine that are commonly used in China,Japan,Korea and elsewhere around the *** the first time,a chapter on traditional medicine was incorporated,which has completely changed the status quo on the lack of information on traditional medicine and health statistics in the *** this study,we systematically analyzed the background,structure,content and characteristics of the Traditional Medicine chapter,with focus on its positive effects on promoting the development and utilization of Traditional Chinese Medicine worldwide.

关键词： International classification of diseases Medicine,traditional Chinese World Health Organization

Understanding of the capacity Contribution of carbon in phosphorus-carbon composites for high-performance anodes in lithium ion batteries

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Nano Research 2017年第4期10卷 1268-1281页

作者： Jiantie Xu In-Yup Jeon Jianmin Ma Yuhai dou Seok-Jin Kim Jeong-Min Seo Huakun Liu Shixue dou Jong-Beom Baek liming Dai Institute for Superconducting and Electronic Materials University of Wollongong Wollongong NSW 2522 Austrafia School of Energy and Chemical Engineering/Low-Dimensional Carbon Materials Center Ulsan National Institute of Science and Technology (UNIST) UNIST-gi150 Ulsan 689-897 Republic of Korea Department of Macromolecular Science and Engineering Case Western Reserve University Cleveland OH 44106 USA

Phosphorus has recently received extensive attention as a promising anode for lithium ion batteries （LIBs） due to its high theoretical capacity of 2,596 mAh·g^-1. To develop high-performance phosphorus anodes for LIBs, carbon materials have been hybridized with phosphorus （P-C） to improve dispersion and con- ductivity. However, the specific capacity, rate capability, and cycling stability of P-C anodes are still less than satisfactory for practical applications. Furthermore, the exact effects of the carbon support on the electrochemical performance of the P-C anodes are not fully understood. Herein, a series of xP-yC anode materials for LIBs were prepared by a simple and efficient ball-milling method. 6P-4C and 3P-7C were found to be optimum mass ratios of x/y, and delivered initial discharge capacities of 1,803.5 and 1,585.3-mAh·g^-1, respectively, at 0.1 C in the voltage range 0.02-2 V, with an initial capacity retention of 68.3% over 200 cycles （more than 4 months cycling life） and 40.8% over 450 cycles. The excellent electrochemical performance of the 6P-4C and 3P-7C samples was attributed to a synergistic effect from both the adsorbed P and carbon.

关键词： phosphorus carbon synergistic effect anode lithium ion batteries

Ternary ReS_(2(1-x))Se_(2x) alloy saturable absorber for passively Q-switched and mode-locked erbium-doped all-fiber lasers

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Photonics Research 2019年第3期7卷 283-288页

作者： CHENXI dou WEN WEN JUNLI WANG MENGYUAN MA liming XIE CHING-HWA HO ZHIYI WEI School of Physics and Optoelectronics Engineering Xidian University CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology University of Chinese Academy of Sciences Graduate Institute of Applied Science and Technology Taiwan University of Science and Technology Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences

We report Q-switched and mode-locked erbium-doped all-fiber lasers using ternary ReS_(2(1-x))Se_(2x) as saturable absorbers(SAs). The modulation depth and saturable intensity of the film SA are 1.8% and 0.046 MW∕*** Q-switched mechanism output, the pulse was centered at 1531.1 nm with maximum pulse energy and minimum pulse width of 28.29 nJ and 1.07 μs, respectively. In mode-locked operation, the pulse was centered at1561.15 nm with pulse width of 888 fs, repetition rate of 2.95 MHz, and maximum pulse energy of 0.275 nJ. To the best of our knowledge, this is the first report on the mode-locked Er^(3+)-doped fiber laser using ternary transition metal dichalcogenides. This work suggests prospective 2 D-material SAs can be widely used in versatile fields due to their attractive optoelectronic and tunable energy bandgap properties.

关键词： Ternary ReS2(1-x)Se2x alloy saturable absorber mode-locked erbium-doped all-fiber lasers Q-switched

Influence of B1 code correlation loop for vector tracking structures under complicated environment

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1053-1063页

作者： WANG Qian SHANG Feng DU liming ZHOU Wenjia School of Electronic Engineering Xi’an University of Posts and Telecommunications Qingdao Huatong Intelligent Research Institute

The code tracking loop is a key component for user positioning. The pseudorange information of Bei dou B1 signals has been fused and changed for vector tracking, so a correlation output model for complex scenarios is designed to prevent the propagation of error and valuate the signal performance. The relevant software and hardware factors that affect the output are analyzed.A single channel time-division multiplexing(TDM) method for multicorrelation data extraction is proposed. Statistical characteristics of the correlation output data for both vector and scalar structures are evaluated. Simulation results show that correlation outputs for both structures follow normal or Chi-squared distributions in normal conditions, and the Gamma distribution in harsh conditions. It is shown that a tracking model based on the multi-channel fusion hardly changes the probability distribution of the correlation output in the normal case, but it reduces the ranging error of the code loop, and hence the tracking ability of the code loop for weak signals is improved. Furthermore, vector tracking changes the pseudorange characteristics of channels anytime, and affects the mutual correlation outputs of the code loops in the abnormal case. This study provides a basis for the subsequent design of autonomous integrity algorithms for vector tracking.

关键词： vector tracking signal quality code correlation pseu dorange error scalar tracking correlation peak loss.