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Uniformity Control of Scanned Beam in 300 MeV Proton and Heavy Ion Accelerator Complex at SESRI

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原子能科学技术 2024年第4期58卷 705-713页

作者： HOU Lingxiao YUAN Youjin SHEN Guodong ruan shuang LIU Jie ZHU Yunpeng WANG Geng GUO Hongliang LYU Mingbang GAO Daqing XU Zhiguo SHENG Lina YANG Jiancheng Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

In recent years,heavy ion accelerator technology has been rapidly developing worldwide and widely applied in the fields of space radiation simulation and particle ***,a very high uniformity in the irradiation area is required for the extracted ion beams,which is crucial because it directly affects the experimental precision and therapeutic ***,ultra-large-area and high-uniformity scanning are crucial requirements for spacecraft radiation effects assessment and serve as core specification for beamline terminal *** the 300 MeV proton and heavy ion accelerator complex at the Space Environment Simulation and Research Infrastructure(SESRI),proton and heavy ion beams will be accelerated and ultimately delivered to three irradiation *** order to achieve the required large irradiation area of 320 mm×320 mm,horizontal and vertical scanning magnets are used in the extraction beam ***,considering the various requirements for beam species and energies,the tracking accuracy of power supplies(PSs),the eddy current effect of scanning magnets,and the fluctuation of ion bunch structure will reduce the irradiation *** mitigate these effects,a beam uniformity optimization method based on the measured beam distribution was proposed and applied in the accelerator complex at *** the experiment,the uniformity is successfully optimized from 75%to over 90%after five iterations of adjustment to the PS *** this paper,the method and experimental results were introduced.

关键词： heavy ion accelerator beam uniformity scanning magnet MIC

Simultaneous production of high-frequency synthetic apomixis with high fertility and improved agronomic traits in hybrid rice

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Molecular Plant 2024年第1期17卷 4-7页

作者： Mengqiu Song Wumei Wang Chun Ji Shengnan Li Wei Liu Xiaoyu Hul Anhui Feng shuang ruan Shiyun Du Huan Wang Kui Dai Longbiao Guo Qian Qian Hongqi Si Xingming Hu College of Agronomy Anhui Agricultural UniversityHefeiAnhui 230036China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhouZhejiang 310006China Rice Research Institute Anhui Academy of Agricultural SciencesHefeiAnhui 230031China Jiangxi Modern Seed Industry Co.NanchangJiangxi 330026China

Dear Editor,Utilization of heterosis is fundamental to modern agricultural improvement and contributes significantly to food security and agricultural development(Ouyang et al.,2022).However,heterosis of F,hybrids cannot be stably ***,or asexual reproduction through seeds,offers the potential for the fixation of heterosis in F,hybrids and the formation of clonal offspring,which could have considerable implications for plant breeding and agriculture(Schmidt,2020).But naturally occurring apomixis has never been found in major ***,synthetic apomixis has been successfully generated by inducing incomplete meiotic development combined with parthenogenesis development to produce cloned rice(Oryza sativa)seeds(Khanday et al.,2019;Wang et al.,2019;Vernet et al.,2022;Wei et al.,2023).

关键词： sativa fertility breeding

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小车式起落架地面载荷与漂浮性分析

航空工程进展 2024年第4期15卷 82-92页

作者：杨钰张明阮爽史夏正南京航空航天大学航空航天结构力学及控制全国重点实验室南京210016 南京航空航天大学飞行器先进设计技术国防重点学科实验室南京210016

飞机起落架与道面的相容性对飞机的地面运动能力具有重要影响。针对某大型飞机计算不同工况下其起落架载荷及轮胎载荷分配,采用基于韦斯特加德层板理论的波特兰水泥协会法和基于加利福尼亚承载比的美国陆军工程兵团方法,计算不同着陆工... 详细信息

飞机起落架与道面的相容性对飞机的地面运动能力具有重要影响。针对某大型飞机计算不同工况下其起落架载荷及轮胎载荷分配,采用基于韦斯特加德层板理论的波特兰水泥协会法和基于加利福尼亚承载比的美国陆军工程兵团方法,计算不同着陆工况、地面机动工况、轮胎数量、轮胎泄气工况、轮胎间距对飞机等级数的影响,分析刚性道面和柔性道面下的飞机漂浮性。结果表明:垂直过载和机轮泄气带来的轮胎载荷增大与载荷分配不均,都会在不同程度上减弱飞机的漂浮性,尤其是转弯和机尾下沉着陆工况需要予以限制;轮胎数量和轮胎间距的增加可以改善漂浮性,需同时考虑结构设计、强度裕度等来优化设计小车式起落架构造。

关键词：地面载荷漂浮性起落架道面加利福尼亚承载比飞机等级数

Wavelength-Tunable Rectangular Pulse Dissipative Soliton Operation of an Erbium-Doped Mode-Locked Fiber Laser

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Chinese Physics Letters 2014年第4期31卷 68-71页

作者： HU Xue-Juan GUO Chun-Yu ruan shuang-Chen Shenzhen Key Laboratory of Laser Engineering Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes College of Electronic Science and Technology Shenzhen University Shenzhen 518060

The wavelength-tunable rectangular pulse dissipative soliton （DS） is experimentally demonstrated, for the first time to the best of our knowledge, in an erbium-doped figure-of-eight fiber laser based on the nonlinear amplifying loop mirror mode-locked technique. The proposed rectangular pulse DS fiber laser can operate in the wavelength- tunable mode-locked state from 1573.5nm to 159d.6 nm with the rotation of the polarization controllers. The achieved output wavelengths are 1573.5nm, 1576.3nm, 1586.8nm, 1590.4nm and 1594.6nm, respectively. The pulse widths of the rectangular pulse can also be tuned from ~8ns to ~24ns by adjusting the pump power. The fundamental repetition rate of the rectangular pulse DS is 1.154 MHz and the output power is 6.1d m W （at 1594.6 nm）.

关键词： Laser Wavelength-Tunable first

Real-time continuous-wave imaging with a 1.63THz OPTL and a pyroelectric camera

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Optoelectronics Letters 2008年第4期4卷 295-298页

作者： YANG Jun ruan shuang-chen ZHANG Min ZHANG We Research Center for Space Optical Engineering Harbin Institute of Technology Harbin 150001 China College of Electronic Science and Technology Shenzhen University Shenzhen 518060 China

Real-time continuous-wave terahertz imaging is demonstrated with a 1.63 THz （184.31 lam） optically-pumped terahertz laser （OPTL） and a 124 × 124 element room-temperature pyroelectric camera. Transmission-mode THz imaging is presented for the samples hidden in various wrapping materials. These experimental results reveal the possibility to construct a simple real-time THz imaging system applied to nondestructive inspection.

关键词：热电照相机光泵浦激光器实时连续波成像太赫成像

Highly Thermally Conductive Polydimethylsiloxane Composites with Controllable 3D GO@f-CNTs Networks via Self-sacrificing Template Method

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Chinese Journal of Polymer Science 2024年第7期42卷 897-906,I0005页

作者： shuang-shuang Wang Dian-Ying Feng Zhi-Ming Zhang Xia Liu Kun-Peng ruan Yong-Qiang Guo Jun-Wei Gu Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an710072China Shandong Institute of Nonmetallic Materials Jinan250031China Queen Mary University of London Engineering School Northwestern Polytechnical UniversityXi’an710072China

Constructing controllable thermal conduction networks is the key to efficiently improve thermal conductivities of polymer *** this work,graphite oxide(GO)and functionalized carbon nanotubes(f-CNTs)are combined to prepare“Line-Plane”-like hetero-structured thermally conductive GO@f-CNTs fillers,which are then performed to construct controllable 3D GO@f-CNTs thermal conduction networks via selfsacrificing template method based on oxalic ***,thermally conductive GO@f-CNTs/polydimethylsiloxane(PDMS)composites are fabricated via casting *** the size of oxalic acid is 0.24 mm and the volume fraction of GO@f-CNTs is 60 vol%,GO@f-CNTs/PDMS composites present the optimal thermal conductivity coefficient(λ,4.00 W·m^(-1)·K^(-1)),about 20 times that of theλof neat PDMS(0.20 W·m^(-1)·K^(-1)),also much higher than theλ(2.44 W·m^(-1)·K^(-1))of GO/f-CNTs/PDMS composites with the same amount of randomly dispersed ***,the obtained GO@f-CNTs/PDMS composites have excellent thermal stability,whoseλdeviation is only about 3%after 500 thermal cycles(20-200℃).

关键词： Polydimethylsiloxane Hetero-structured thermally conductive fillers Self-sacrificing template Thermal conduction networks

Q-Switched Thulium-Doped Domestic Silica Fiber Laser

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Chinese Physics Letters 2011年第4期28卷 112-114页

作者： HU Hui DU Ge-Guo YAN Pei-Guang ZHAO Jun-Qing GUO Chun-Yu ruan shuang-Chen Shenzhen Key Laboratory of Laser Engineering College of Electronic Science and TechnologyShenzhen UniversityShenzhen 518060

We report a cladding-pumped Tm^(3+)-doped domestic silica fiber laser operated at 2pm and actively Q-switched with an acousto-optic *** trains are obtained as pumped by a 785nm laser *** maximum average output power is *** power up to 4.2kW and pulse energy up to 840μJ are obtained with the pulse duration of 200ns produced at a repetition rate of 1 *** laser performance is studied under different repetition rates and pump ***,we give some discussion.

关键词： pumped laser pulse

Analysis and mitigation of bump magnetic field tracking errors in a multiturn injection system

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Radiation Detection Technology and Methods 2023年第4期7卷 531-544页

作者： Shuaishuai Zhang Guodong Shen Weiping Chai Jingjing Zhang Hongliang Guo Lingxiao Hou Liping Yao shuang ruan Jiancheng Yang Institute of Modern Physics Chinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

Purpose The Space Environment Simulation and Research Infrastructure(SESRI)is a cluster of accelerators designed to simulate the cosmic radiation environment by generating particles of various types and *** these accelerators,a synchrotron in the 300 MeV proton and heavy ion accelerator complex utilizes a multiturn injection scheme with four bump magnets to accumulate proton and heavy ion beams ***,the bump magnetic field experiences a rapid drop rate of up to 1000 T/s,inevitably leading to a deviation(field tracking error)from the ideal magnetic *** injection efficiency and particle distribution are significantly affected by this field tracking error,as evaluated by the ACCSIM *** During the device testing stage,the sources of field tracking errors were identified by analysis of the bump power supplies and the field of the *** techniques were then implemented to reduce the field tracking error from[Math Processing Error]to[Math Processing Error]throughout the entire power supply,transmission cable,and magnet *** Moreover,the successful injection and accumulation of beams during the operational phase of the synchrotron confirmed the effectiveness of the proposed mitigation ***,a magnetic field measurement system was developed to monitor the magnetic field tracking error *** The combination of the field tracking error mitigation methods and the measurement system provides valuable guidance for optimizing the magnetic fields with rapid drop rates.

关键词： SESRI Multiturn injection Bump magnet Field tracking error mitigation

H_(2)-Assistance One-Step Growth of Si Nanowires and Their Growth Mechanism

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Chinese Physics Letters 2011年第10期28卷 173-175页

作者： QIU Ming-Xia ruan shuang-Chen GAO Biao HUO Kai-Fu ZHAI Jian-Pang LI Ling LIAO Hui XU Xin-Tong Shenzhen Key Laboratory of Laser Engineering College of Electronic Science and TechnologyShenzhen UniversityShenzhen 518060 College of Materials and Metallurgy Wuhan University of Science and TechnologyWuhan 430081

Large-scale nanowires are grown on Si wafers by the catalyst-free one-step thermal reaction method in Ar/H_(2) mixture atmosphere at 1000°*** x−ray diffraction and energy dispersive x-ray spectroscopy results reveal that the final nanowires are of silicon *** field emission scanning electron microscopy shows that these self-organized Si nanowires(SiNWs)possess curly crowns with diameters varying from 10 to 300 nm and lengths of up to several hundreds of *** transmission electron microscopy indicates that the nanowires are pure Si with amorphous *** the measurement results show that no silicon oxide is generated in our *** growth mechanism is proposed *** oxide is reduced into Si nanoparticles under the Ar/H_(2) mixture,which is the main reason for the formation of such *** experiments offer a method of preparing Si nanostructures by simply reducing silicon oxide at high temperature.

关键词： nanowires preparing hundreds