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Development of High Intensity Beam Emittance Measurement Unit

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 287-291页

作者： LV pengNan peng shixiang GUO ZhiYu YUAN ZhongXi REN HaiTao ZHAO Jie ZHANG Meng CHEN JiaEr LU YuanRong State Key Laboratory of Nuclear Physics and Technology&Institute of Heavy Ion Physics Peking UniversityBeijing 100871China Graduate University of Chinese Academy of Sciences Beijing 100049China

Three sets of High Intensity Beam Emittance Measurement Units (HIBEMUs) are being developed at Peking University. They are HIBEMU-2 (slit-wire type, one direction), HIBEMU-3 (Allison scanner type, one direction) and HIBEMU-4 (slit-wire type, two directions). For HIBEMU-2 and HIBEMU-3, more recent work has been done on software redesign in order to measure beam emittance and to draw phase diagram more efficiently and precisely. Software for control and data processing of them were developed in Labveiw environment, trying to improve calculation rationality and to offer user-friendly interface. Mechanical modification was also done for HIBEMU-3, mainly concentrating on the protection of Faraday cups from being overheated by the high intensity beam and also from interference of secondary electrons. This paper will also cover the mechanical structure as well as the software development of HIBEMU-4, which is a two-direction emittance scanner newly designed and manufactured for the high energy beam transport (HEBT) of Peking University Neutron Imaging FaciliTY (PKUNIFTY). At the end of this paper, comparison and analysis of the three HIBEMUs are given to draw forth better design of the future emittance measurement facility.

关键词： emittance HIBEMU high intensity beam user-friendly program comparison.

Plasma parameter diagnosis using hydrogen emission spectra of a quartz-chamber 2.45 GHz ECRIS at Peking University

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Science China(Physics,Mechanics & Astronomy) 2018年第4期61卷 69-74页

作者： WenBin Wu HaiTao Ren shixiang peng Yuan Xu JiaMei Wen Tao Zhang JingFeng Zhang AiLin Zhang Jiang Sun ZhiYu Guo JiaEr Chen State Key Laboratory of Nuclear Physics and Technology & Institute of Heavy Ion Physics Peking University

A quartz-chamber 2.45 GHz electron cyclotron resonance ion source(ECRIS) was designed for diagnostic purposes at Peking University [Patent Number: ZL 201110026605.4]. This ion source can produce a maximum 84 m A hydrogen ion beam at 50 k V with a duty factor of 10%. The root-mean-square(RMS) emittance of this beam is less than 0.12π mm mrad. In our initial work,the electron temperature and electron density inside the plasma chamber had been measured with the line intensity ratio of noble gases. Based on these results, the atomic and molecular emission spectra of hydrogen were applied to determine the dissociation degree of hydrogen and the vibrational temperature of hydrogen molecules in the ground state, respectively. Measurements were performed at gas pressures from 4×10^(-4) to 1×10^(-3) Pa and at input peak RF power ranging from 1000 to 1800 W. The dissociation degree of hydrogen in the range of 0.5%-10% and the vibrational temperature of hydrogen molecules in the ground state in the range of 3500-8500 K were obtained. The plasma processes inside this ECRIS chamber were discussed based on these results.

关键词： electron cyclotron resonance ion source(ECRIS) hydrogen plasma optical emission spectroscopy dissociation degree of hydrogen vibrational temperature

Multiple charge ion beam generation with a 2.45 GHz electron cyclotron resonance ion source

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Science China(Physics,Mechanics & Astronomy) 2017年第6期60卷 74-77页

作者： Yuan Xu shixiang peng HaiTao Ren JiaMei Wen AiLin Zhang Tao Zhang JingFeng Zhang WenBin Wu ZhiYu Guo JiaEr Chen State Key Laboratory of Nuclear Physics and Technology & Institute of Heavy Ion Physics Peking University Beijing 100871 China University of Chinese Academy of Sciences Beijing 100049 China

Multiple charge ions (MCIs) are necessary for increasing the output energy of particles in accelerators. In general, MCI beams are largely produced by electron beam ion source (EBIS) [1], laser ion source (LIS) [2], or high-frequency (mostly >5 GHz) electron cyclotron resonance (ECR) ion source [3]. Among these, only ECR ion source can operate in the continuous wave (CW) mode, while EBIS and LIS only support pulses. In addition, ECR ion source with lower frequency (mostly 2.45 GHz) are required primarily for generating single charge state ions, because the corresponding ECR field (875 Gs) is not sufficiently strong for MCI generation [4].

关键词： mostly operate generating sufficiently primarily largely

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材料表面处理用强流电子回旋共振离子源

强激光与粒子束 2012年第12期24卷 2911-2914页

作者：明建川郭之虞彭士香北京大学核物理与核技术国家重点实验室北京100871

介绍一台2.45GHz永磁强流电子回旋共振离子源,其外径160mm,高90mm,放电室直径70mm,高50mm。微波馈入采用介质耦合方式,微波窗由一块50mm×10mm柱形BN和两块30mm×10mm的柱形陶瓷构成。离子源工作在脉冲模式下,采用三电极引出系统,... 详细信息

介绍一台2.45GHz永磁强流电子回旋共振离子源,其外径160mm,高90mm,放电室直径70mm,高50mm。微波馈入采用介质耦合方式,微波窗由一块50mm×10mm柱形BN和两块30mm×10mm的柱形陶瓷构成。离子源工作在脉冲模式下,采用三电极引出系统,最高引出电压达到100kV,在微波输入功率300W、进气量0.4mL/min时,可引出峰值超过30mA的氮离子束,在距离离子源引出孔1200mm位置处的束流均匀区直径大于200mm。

关键词：电子回旋共振离子源微波窗表面处理引出系统

Progress in the beam commissioning of separated function RFQ accelerator

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 222-224页

作者： MingLei Kang (1) YuanRong Lu (1) Zhi Wang (1) Kun Zhu (1) XueQing Yan (1) ZhiYu Guo (1) ShuLi Gao (1) shixiang peng (1) Ao Liu (2) JiaXun Fang (1) JiaEr Chen (1) 1. State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China2. Department of Physics Indiana University Bloomington IN 47405 USA

Separated Function RFQ (SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low frequency. It introduces gap accelerating in the quadrupole electrodes, and therefore it has higher accelerating efficiency than the conventional RFQ accelerator. The first SFRFQ prototype cavity has been specially designed and constructed as a post accelerator to accelerate O+ beam from 1.03 MeV to 1.64 MeV. Based on accomplishment of low power measurement and high power test, the beam commissioning was carried out to verify its feasibility. The measured energy gain per cell of SFRFQ is 45 keV, which is about 60% higher than that of Peking University Integral Split Ring (ISR) RFQ.

关键词： separated function RFQ beam commissioning energy spectrum

Unveiling size-fluorescence correlation of organic nanoparticles and its use in nanoparticle size determination

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Aggregate

Aggregate 2024年第1期5卷 331-336页

作者： Wu-Jie Guo shixiang Ma Hui Wang Lu Qiao Lei Chen Chenyu Hong Bin Liu Xiaoyan Zheng Hui-Qing peng State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijingChina Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electro-photonic Conversion MaterialsKey Laboratory of Medicinal Molecule Science and Pharmaceutics Engineering of Ministry of Industry and Information TechnologySchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijingChina

Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles(FNPs).However,such exploration focusing on organic FNPs has not been achieved to ***,we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene-based bis-ureidopyrimidinone monomers(bis-UPys)to relate the size to the fluorescence of organic *** an equal concentration of bis-UPys,a logarithmic relationship between them is built with a correlation coefficient higher than *** calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the *** leads to different nonradiative decay rates of the embedded and exposed bis-UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface *** established fluorescence intensity-size correlation possesses fine universality and reliability,and it is successfully utilized to estimate the sizes of other nanoparticles,including those in highly diluted dispersions of *** work paves a new way for the simple and real-time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect.

关键词： aggregation-induced emission fluorescence detection fluorescent nanoparticle nanoparticle size supramolecular polymer

Development of High Intensity Beam Emittance Measurement Unit

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Development of High Intensity Beam Emittance Measurement Uni...

Progress in the beam commissioning of separated function RFQ accelerator

第一届中国粒子加速器会议

作者： LV pengNan peng shixiang GUO ZhiYu YUAN ZhongXi REN HaiTao ZHAO Jie ZHANG Meng CHEN JiaEr LU YuanRong State Key Laboratory of Nuclear Physics and Technology & Institute of Heavy Ion Physics Peking University Graduate University of Chinese Academy of Sciences

Three sets of High Intensity Beam Emittance Measurement Units(HIBEMUs) are being developed at Peking *** are HIBEMU-2(slit-wire type,one direction),HIBEMU-3(Allison scanner type,one direction) and HIBEMU-4(slit-wire type, two directions).For HIBEMU-2 and HIBEMU-3,more recent work has been done on software redesign in order to measure beam emittance and to draw phase diagram more efficiently and *** for control and data processing of them were developed in Labveiw environment,trying to improve calculation rationality and to offer user-friendly interface. Mechanical modification was also done for HIBEMU-3,mainly concentrating on the protection of Faraday cups from being overheated by the high intensity beam and also from interference of secondary *** paper will also cover the mechanical structure as well as the software development of HIBEMU-4,which is a two-direction emittance scanner newly designed and manufactured for the high energy beam transport(HEBT) of Peking University Neutron Imaging FaciliTY (PKUNIFTY).At the end of this paper,comparison and analysis of the three HIBEMUs are given to draw forth better design of the future emittance measurement facility.

关键词： emittance HIBEMU high intensity beam user-friendly program comparison

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Progress in the beam commissioning of separated function RFQ...

Antagonistic MADS-box transcription factors SEEDSTICK and SEPALLATA3 form a transcriptional regulatory network that regulates seed oil accumulation

第一届中国粒子加速器会议

作者： KANG MingLei LU YuanRong WANG Zhi ZHU Kun YAN XueQing GUO ZhiYu GAO ShuLi peng shixiang LIU Ao FANG JiaXun CHEN JiaEr State Key Laboratory of Nuclear Physics and Technology Peking University Department of Physics Indiana University

Separated Function RFQ(SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low *** introduces gap accelerating in the quadrupole electrodes,and therefore it has higher accelerating efficiency than the conventional RFQ *** first SFRFQ prototype cavity has been specially designed and constructed as a post accelerator to accelerate O beam from 1.03 MeV to 1.64 *** on accomplishment of low power measurement and high power test,the beam commissioning was carried out to verify its *** measured energy gain per cell of SFRFQ is 45 keV,which is about 60%higher than that of Peking University Integral Split Ring(ISR) RFQ.

关键词： separated function RFQ beam commissioning energy spectrum

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Journal of Integrative Plant Biology 2024年第1期66卷 121-142页

作者： Shuangcheng He Yuanchang Min Zijin Liu Fang Zhi Rong Ma Ankang Ge shixiang Wang Yu Zhao Danshuai peng Da Zhang Minshan Jin Bo Song Jianjun Wang Yuan Guo Mingxun Chen State Key Laboratory for Crop Stress Resistance and High‐Efficiency Production National Yangling Agricultural Biotechnology&Breeding CenterShaanxi Key Laboratory of Crop HeterosisCollege of AgronomyNorthwest A&F UniversityYangling 712100China State Key Laboratory for Crop Stress Resistance and High‐Efficiency Production Shaanxi Key Laboratory of AppleCollege of HorticultureNorthwest A&F UniversityYangling 712100China

Transcriptional regulation is essential for balancing multiple metabolic pathways that influence oil accumulation in *** far,the transcriptional regulatory mechanisms that govern seed oil accumulation remain largely ***,we identified the transcriptional regulatory network composed of MADS-box transcription factors SEEDSTICK(STK)and SEPALLATA3(SEP3),which bridges several key genes to regulate oil accumulation in *** found that STK,highly expressed in the developing embryo,positively regulates seed oil accumulation in Arabidopsis(Arabidopsis thaliana).Furthermore,we discovered that SEP3 physically interacts with STK in vivo and in *** oil content is increased by the SEP3 mutation,while it is decreased by SEP3 *** chromatin immunoprecipitation,electrophoretic mobility shift assay,and transient dual-luciferase reporter assays showed that STK positively regulates seed oil accumulation by directly repressing the expression of MYB5,SEP3,and SEED FATTY ACID REDUCER 4(SFAR4).Moreover,genetic and molecular analyses demonstrated that STK and SEP3 antagonistically regulate seed oil production and that SEP3 weakens the binding ability of STK to MYB5,SEP3,and ***,we demonstrated that TRANSPARENT TESTA 8(TT8)and ACYL-ACYL CARRIER PROTEIN DESATURASE 3(AAD3)are direct targets of MYB5 during seed oil accumulation in ***,our findings provide the transcriptional regulatory network antagonistically orchestrated by STK and SEP3,which fine tunes oil accumulation in seeds.

关键词： seed oil accumulation SEP3 STK transcription factor transcriptional regulation