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BRIGHT:the three-dimensional X-ray crystal Bragg diffraction code

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Nuclear Science and Techniques 2019年第3期30卷 28-36页

作者： Nan-Shun Huang Kai Li hai-xiao deng Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Physics The University of Chicago

In pursuit of a fully coherent X-ray free-electron laser(FEL), highly reflective Bragg crystals are used and will be used as a highly selective spectral filter in hard X-ray self-seeding FELs and X-ray FEL oscillators(XFELO), respectively. However, currently, when simulating self-seeding and XFELO, the three-dimensional effect of Bragg diffraction is not fully considered. In this paper, we derive a comprehensive solution for the response function of the crystal in Bragg diffraction. A three-dimensional X-ray crystal Bragg diffraction code, named BRIGHT, is introduced, which can be combined with other FEL-related codes, e.g., GENESIS and OPC. Performance and feasibility are assessed using two numerical examples,namely a self-seeding experiment for the linac coherent light source and XFELO options for Shanghai high repetition rate XFEL. The results indicate that BRIGHT provides a new and useful tool for three-dimensional modeling of FEL.

关键词： X-ray Bragg diffraction Self-seeding XFELO

Wakefields studies for the SXFEL user facility

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Nuclear Science and Techniques 2017年第7期28卷 29-35页

作者： Ming-Hao Song Chao Feng Da-Zhang Huang hai-xiao deng Bo Liu Dong Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesZhangjiang CampusShanghai 201204China University of Chinese Academy of Sciences Beijing 100049China

Besides the original seeded undulator line,in the soft X-ray free-electron laser(SXFEL) user facility in Shanghai,a second undulator line based on self-amplified spontaneous emission is proposed to achieve 2-nm laser pulse with extremely high *** this paper,the beam energy deviation induced by the undulator wakefields is numerically calculated,and 3D and 2D results agree well with each *** beam energy loss along the undulator degrades the expected FEL output performances,i.e.,the pulse energy,radiation power and spectrum,which can be compensated with a proper taper in the *** the planned time-resolved diagnostic,a novel experiment is proposed to measure the SXFEL longitudinal wakefields.

关键词：用户设备能量耦合自由电子激光自放大自发辐射波荡器软X射线激光脉冲数值计算

Development of a high-repetition-rate lumped-inductance kicker magnet prototype for the beam switchyard of SHINE

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Nuclear Science and Techniques 2024年第2期35卷 20-31页

作者： Yong-Fang Liu Rui-Ping Wang Jin Tong Bo Zhang Si Chen Qi-Bing Yuan hai-xiao deng Ming Gu Bo Liu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201412People’s Republic of China

The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 *** magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch *** kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn *** full magnetic field strength was 0.005 *** paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker *** relevant experimental results are also *** pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 *** developed kicker satisfies the requirements for the SHINE ***,numerous recommendations for the future optimization of kicker magnets are provided.

关键词： X-ray free-electron laser Kicker magnet Beam switchyard High repetition rate Ni-Zn ferrites

Mapping of Rice Fertility-Restoring Genes for ID-Type Cytoplasmic Male Sterility in a Restorer Line R68

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Rice science 2008年第2期15卷 157-160页

作者： LI Liang-jie ZHOU hai-peng ZHAN xiao-deng CHENG Shi-hua CAO Li-yong State Key Laboratory of Rice Biology/Chinese National Center for Rice Improvement China National Rice Research Institute Hangzhou 310006 China

An F2 population derived from the cross Zhong 9A/R68 was used to map the fertility-restoring （Rf） gene for ID-type cytoplasmic male sterility （CMS）. Two bulks （a fertile bulk and a sterile bulk） were constructed by pooling equal amount of ten highly fertile lines and ten highly sterile lines, respectively. Four hundred and thirteen pairs of simple sequence repeat （SSR） primers, which evenly distributed on 12 chromosomes of rice, were selected for analyzing polymorphisms between the parents and between the two bulks. The primer RM283 on chromosome 1 and the primers RM5756, RM258, RM6100 and RM171 on chromosome 10 were found to be polymorphic between the parents and between the two bulks. These five SSR markers were linked to fertility-restoring genes. A total of 82 excessive sterile lines were selected from Zhong 9A/R68 F2 population to estimate the genetic distance between five SSR markers and fertility-restoring genes respectively. The results indicated that one Rf gene was linked to RM283 located on chromosome 1 at a distance of 6.7 cM, and the other Rfgene was mapped to the long arm of chromosome 10 flanked by RM258 and RM6100 at the distances of 8.0 cM and 2.4 cM, respectively.

关键词： rice cytoplasmic male sterility fertility-restoring gene gene mapping

Beam dynamics optimization of very-high-frequency gun photoinjector

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Nuclear Science and Techniques 2022年第9期33卷 80-92页

作者： Han Chen Lian-Min Zheng Bin Gao Zi-Zheng Li Ying-Chao Du Ren-Kai Li Wen-Hui Huang Chuan-Xiang Tang Duan Gu Zheng Qi Meng Zhang hai-xiao deng Qiang Gu Dong Wang Department of Engineering Physics Tsinghua UniversityBeijing 100084China Chinese Academy of Sciences Shanghai Institute of Applied PhysicsShanghai 201800China Chinese Academy of Sciences Shanghai Advanced Research InstituteShanghai 201210China

Very-high-frequency(VHF)gun photoinjectors,capable of producing high-brightness and high-repetitionrate electron bunches,are some of the best electron sources for driving MHz-class repetition-rate free-electron *** this study,the beam dynamics optimization of a VHF gun photoinjector for Shanghai HIgh Repetition Rate X-ray Free Electron Laser and Extreme Light Facility(SHINE)is systematically demonstrated using a genetic *** the inclusion of the solenoid geometry as an optimization variable into the genetic algorithm,the optimum projected normalized emittance for 100 pC bunches with bunch length of 1 mm rms is reduced to 0.1 mm mrad for 100%of the particles and 0.075 mm mrad for 95%of the particles,proving that sub-100 nm emittance can be achieved in the SHINE injector using a single-cell Tsinghua University(THU)VHF *** emittance fulfills the requirements not only of SHINE and Linac Coherent Light Source(LCLS)-II but also of LCLS-II-High Energy(LCLS-II-HE).We demonstrate that the optimal emittance in the VHF gun injector is reduced via the optimization of the solenoid geometry,thereby reducing solenoid spherical *** the inclusion of high-order(H.O.)energy spread among the optimization objectives,the *** spread can be reduced by a factor of nearly six using a high-harmonic cavity despite a 38%emittance ***,the beam dynamics in the SHINE main accelerator show that reducing the *** spread in the injector is of great significance to improving compression efficiency and reducing bunch current spike.

关键词： VHF gun photoinjector Multi-objective optimization Emittance High-order energy spread

COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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Science China(Information Sciences) 2025年第1期68卷 189-203页

作者： xiaoqin ZHANG Zhenni YU Li ZHAO deng-Ping FAN Guobao xiao Zhejiang Province Key Laboratory of Intelligent Informatics for Safety and Emergency Wenzhou University Nankai International Advanced Research Institute (SHENZHEN FUTIAN) College of Computer Science Nankai University School of Computer Science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

同方期刊数据库

First commissioning results of the coherent scattering and imaging endstation at the Shanghai soft X-ray free-electron laser facility

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Nuclear Science and Techniques 2022年第9期33卷 48-58页

作者： Jia-Dong Fan Ya-Jun Tong Yong-Gan Nie Zi-Chen Gao Bo He Hui Luan Dong-Hao Lu Jian-Hua Zhang Di-Fei Zhang Xin-Ye Yuan Jia-Hua Chen Zhi Guo Tao Liu Meng Zhang Chao Feng hai-xiao deng Bo Liu Zhen-Tang Zhao Zhi Liu Huai-Dong Jiang Center for Transformative Science ShanghaiTech UniversityShanghai 201210China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The Shanghai soft X-ray free-electron laser(SXFEL)user facility project started in 2016 and is expected to be open to users by *** aims to deliver ultra-intense coherent femtosecond X-ray pulses to five endstations covering a range of 100–620 eV for ultrafast X-ray *** undulator lines are designed and constructed,based on different lasing modes:self-amplified spontaneous emission and echo-enabled harmonic *** coherent scattering and imaging(CSI)endstation is the first of five endstations to be commissioned *** focuses on high-resolution single-shot imaging and the study of ultrafast dynamic processes using coherent forward scattering *** the single-shot holograms and coherent diffraction patterns were recorded and reconstructed for nanoscale imaging,indicating the excellent coherence and high peak power of the SXFEL and the possibility of‘‘diffraction before destruction’’experiments at the CSI *** this study,we report the first commissioning results of the CSI endstation.

关键词： X-ray free electron laser Coherent diffraction imaging Fourier transform holography Single-shot imaging Phase retrieval

The MING proposal at SHINE:megahertz cavity enhanced X‑ray generation

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Nuclear Science and Techniques 2023年第1期34卷 51-85页

作者： Nan‑Shun Huang Zi‑Peng Liu Bang‑Jie deng Zi‑Han Zhu Shao‑Hua Li Tao Liu Zheng Qi Jia‑Wei Yan Wei Zhang Sheng‑Wang Xiang Yang‑Yang Lei Ya Zhu Yong‑Zhou He Qi‑Bing Yuan Fei Gao Rong‑Bing deng Sen Sun Zhi‑Di Lei Zhi‑Qiang Jiang Meng‑Qi Duan Yuan Zhuan Xue‑Fang Huang Peng‑Cheng Dong Zhong‑Liang Li Shang‑Yu Si Lian Xue Si Chen Yong‑Fang Liu Ya‑Jun Tong hai‑xiao deng Zhen‑Tang Zhao Zhangjiang Laboratory Shanghai 201210China School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049ShaanxiChina Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China European XFEL Schenefeld 22869Germany ShanghaiTech University Shanghai 201210China

The cavity-based X-ray free-electron laser(XFEL)has promise in producing fully coherent pulses with a bandwidth of a few meV and very stable intensity,whereas the currently existing self-amplified spontaneous emission(SASE)XFEL is capable of generating ultra-short pulses with chaotic *** general,a cavity-based XFEL can provide a spectral brightness three orders of magnitude higher than that of the SASE mode,thereby opening a new door for cutting-edge scientific *** the development of superconducting MHz repetition-rate XFEL facilities such as FLASH,European-XFEL,LCLS-II,and SHINE,practical cavity-based XFEL operations are becoming increasingly *** this study,megahertz cavity enhanced X-ray generation(MING)is proposed based on China’s first hard XFEL facility-SHINE,which we refer to as MING@SHINE.

关键词： X-ray free-electron laser Free electron laser oscillator Fully coherent X-ray

Smart Cellulose‑Based Janus Fabrics with Switchable Liquid Transportation for Personal Moisture and Thermal Management

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Nano-Micro Letters 2025年第1期17卷 333-347页

作者： Jianfeng Xi Yanling Lou Liucheng Meng Chao deng Youlu Chu Zhaoyang Xu Huining xiao Weibing Wu Jiangsu Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsJiangsu Provincial Key Lab of Sustainable Pulp and Paper Technology and Biomass MaterialsNanjing Forestry UniversityNanjing 210037People’s Republic of China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037People’s Republic of China Department of Chemical Engineering University of New BrunswickFrederictonNB E3B 5A3Canada Macromolecular Chemistry and Bavarian Polymer Institute University of BayreuthBayreuth 95440Germany

The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human ***,the development of smart and dynamic fabrics capable of managing personal moisture/thermal comfort in response to changing external environments remains a ***,a smart cellulose-based Janus fabric was designed to dynamically manage personal moisture/*** cotton fabric was grafted with N-isopropylacrylamide to construct a temperature-stimulated transport ***,hydrophobic ethyl cellulose and hydrophilic cellulose nanofiber were sprayed on the bottom and top sides of the fabric to obtain wettability *** fabric exhibits anti-gravity directional liquid transportation from hydrophobic side to hydrophilic side,and can dynamically and continuously control the transportation time in a wide range of 3–66 s as the temperature increases from 10 to 40℃.This smart fabric can quickly dissipate heat at high temperatures,while at low temperatures,it can slow down the heat dissipation rate and prevent the human from becoming too *** addition,the fabric has UV shielding and photodynamic antibacterial properties through depositing graphitic carbon nitride nanosheets on the hydrophilic *** smart fabric offers an innovative approach to maximizing personal comfort in environments with significant temperature variations.

关键词： Directional water transport Cotton fabric Anti-gravity directional liquid transportation Janus wettability