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Fast X-ray imaging beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 68-81页

作者： Ke Li Hong-Lan Xie Ya-Nan Fu Fei-Xiang Wang Guo-Hao Du Jian-Feng ji Biao Deng Ti-Qiao Xiao Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

The fast X-ray imaging beamline(BL16U2)at Shanghai Synchrotron Radiation Facility(SSRF)is a new beamline that provides X-ray micro-imaging capabilities across a wide range of time scales,spanning from 100 ps toμs and *** beamline has been specifically designed to facilitate the investigation of a wide range of rapid phenomena,such as the deformation and failure of materials subjected to intense dynamic *** addition,it enables the study of high-pressure and high-speed fuel spray processes in automotive *** light source of this beamline is a cryogenic permanent magnet undulator(CPMU)that is cooled by liquid *** CPMU can generate X-ray photons within an energy range of 8.7-30 *** beamline offers two modes of operation:monochromatic beam mode with a liquid nitrogen-cooled double-crystal monochromator(DCM)and pink beam mode with the first crystal of the DCM out of the beam *** X-ray imaging methods were implemented in BL16U2:single-pulse ultrafast X-ray imaging,microsecond-resolved X-ray dynamic imaging,millisecond-resolved X-ray dynamic micro-CT,and high-resolution quantitative ***,BL16U2 is equipped with various in situ impact loading systems,such as a split Hopkinson bar system,light gas gun,and fuel spray *** the completion of the final commissioning in 2021 and subsequent trial operations in 2022,the beamline has been officially available to users from 2023.

关键词： Multiple time-scale X ray imaging Single-pulse X ray imaging Dynamic 2D imaging Dynamic micro-CT

High-repetition-rate and high-power efficient picosecond thin-disk regenerative amplifier

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High Power Laser Science and Engineering 2024年第2期12卷 16-23页

作者： Sizhi Xu Yubo Gao Xing Liu Yewang Chen Deqin Ouyang Junqing Zhao Minqiu Liu Xu Wu Chunyu Guo Cangtao Zhou Qitao Lue Shuangchen Ruan Key Laboratory of Advanced Optical Precision Manufacturing Technology of Guangdong Higher Education Institutes Sino-German College of Intelligent ManufacturingShenzhen Technology UniversityShenzhenChina Han’s Laser Technology Industry Group Co. Ltd.ShenzhenChina Shenzhen Key Laboratory of Laser Engineering College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology College of Engineering PhysicsShenzhen Technology UniversityShenzhenChina

We present an effective approach to realize a highly efficient,high-power and chirped pulse amplification-free ultrafast ytterbium-doped yttrium aluminum garnet thin-disk regenerative amplifier pumped by a zero-phonon line 969 nm laser *** amplifier delivers an output power exceeding 154 W at a pulse repetition rate of 1 MHz with custom-designed 48 pump *** exceptional thermal management on the thin disk through high-quality bonding,efficient heat dissipation and a fully locked spectrum collectively contributes to achieving a remarkable optical-to-optical efficiency of 61%and a near-diffraction-limit beam quality with an M2 factor of *** the best of our knowledge,this represents the highest conversion efficiency reported in ultrafast thin-disk regenerative ***,the amplifier operates at room temperature and exhibits exceptional stability,with root mean square stability of less than 0.33%.This study significantly represents advances in the field of laser amplification systems,particularly in terms of efficiency and average *** advantageous combination of high efficiency and diffraction limitation positions the thin-disk regenerative amplifier as a promising solution for a wide range of scientific and industrial applications.

关键词： high efficiency high power picosecond laser regenerative amplifier thin-disk laser

Rock and Soil Classification Using PLS-DA and SVM Combined with a Laser-Induced Breakdown Spectroscopy Library

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Plasma Science and Technology 2015年第8期17卷 656-663页

作者：杨光乔淑君陈鹏飞丁宇田地 College of Instrumentation and Electrical Engineering Jilin University

Laser-induced breakdown spectroscopy （LIBS） has become a powerful technology in geological applications. The correct identification of rocks and soils is critical to many geological projects. In this study, LIBS database software with a user-friendly and intuitive interface is developed based on Windows, consisting of a database module and a sample identification module. The database module includes a basic database containing LIBS persistent lines for elements and a dedicated geological database containing LIBS emission lines for several rock and soil reference standards. The module allows easy use of the data. A sample identification module based on partial least squares discriminant analysis （PLS-DA） or support vector machine （SVM） algorithms enables users to classify groups of unknown spectra. The developed system was used to classify rock and soil data sets in a dedicated database and the results demonstrate that the system is capable of fast and accurate classification of rocks and soils, and is thus useful for the detection of geological materials.

关键词： laser-induced breakdown spectroscopy spectral database geomaterial clas-sification partial least squares discriminant analysis (PLS-DA) support vector machine(SVM)

Two Rhodamine-based Turn on Chemosensors with High Sensitivity, Selectivity, and Naked-Eye Detection for Hg^2＋

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Chinese Journal of Chemical Physics 2017年第2期30卷 225-230,I0002页

作者：周妍闫力强孔志能杜文琦吴宝赢祁争健东南大学化学化工学院南京211189

Two novel rhodamine-based fluorescence enhanced molecular probes （RA1 and RA2） were synthesized, which were both designed as comparative fiuoroionophore and chromophore for the optical detection of Hg^2＋. The recognizing behaviors were investigated both experimentally and computationally. They exhibited high selectivity and sensitivity for Hg^2＋ over other commonly coexistent metal ions in CH3CN/H2O （1：1, V/V） solution. Test shows that hydroxy benzene of rich electron was beneficial to the chelate of Hg^2＋ with sensors. The detection limit was measured to be at least 0.14 ***/L. After addition of Hg^2＋, the color changed from colourless to pink, which was easily and hydrogel sensor. detected by the naked eye in both solution

关键词： Fluorescent sensor Rhodamine Mercury

development of an Automated LIBS Analytical Test System Integrated with Component Control and Spectrum Analysis Capabilities

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Plasma Science and Technology 2015年第8期17卷 704-710页

作者：丁宇田地陈飞鹏陈鹏飞乔淑君杨光李春生 College of Instrumentation & Electrical Engineering Jilin University

The present paper proposes an automated Laser-Induced Breakdown Spectroscopy （LIBS） analytical test system, which consists of a LIBS measurement and control platform based on a modular design concept, and a LIBS qualitative spectrum analysis software and is developed in C#. The platform provides flexible interfacing and automated control; it is compatible with different manufacturer component models and is constructed in modularized form for easy ex- pandability. During peak identification, a more robust peak identification method with improved stability in peak identification has been achieved by applying additional smoothing on the slope obtained by calculation before peak identification. For the purpose of element identification, an improved main lines analysis method, which detects all elements on the spectral peak to avoid omission of certain elements without strong spectral lines, is applied to element identification in the tested LIBS samples. This method also increases the identification speed. In this paper, actual applications have been carried out. According to tests, the analytical test system is compatible with components of various models made by different manufacturers. It can automatically control components to get experimental data and conduct filtering, peak identification and qualitative analysis, etc. on spectral data.

关键词： automated qualitative measurement and control peak identification

Femtosecond Laser Pulses for Drilling the Shaped Micro-Hole of Turbine Blades

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Chinese Physics Letters 2013年第4期30卷 77-80页

作者： JIA Hai-Ni YANG Xiao-Jun ZHAO Wei ZHAO Hua-Long DU Xu YANG Yong Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710119 national Time Service Center Chinese Academy of SciencesXi'an 710600

We design a set of processing devices to drill the shaped holes of turbine blades by using a femtosecond laser which outputs 1064 nm 5 W pulses at 100 kHz,investigate the mechanism of the femtosecond laser interaction with metals,and demonstrate that ultrafast laser drilling has distinct strong points against electric spark and longer laser pulse *** advantages related to no recast layer,no thermal effect,no micro crack,high precision,and high processing efficiency are carried out.

关键词： Femto Turbine Pulse

Design of Measuring Instrument with Whole Direct Method for Bed Shear Stress Under Two-Dimensional Water-Flow Co-action

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China Ocean Engineering 2016年第6期30卷 916-925页

作者：黄海龙左其华周益人沈雨生李蓝汐 Nanjing Hydraulic Research Institute Nanjing 210029China Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing 210024China Business School Hohai UniversityNanjing 210098China

The present study aims at the design and making of measuring instrument of whole direct method for bed shear stress under two-dimensional water-flow co-action. The instrument combines the traditional strain gauge with a precise pressure gauge, and adopts the method directly measuring the difference between the lateral hydrodynamic pressure and different head pressures on both sides of the force plate. As a result, such an instrument solves a technical puzzle of the past strain gauge, i.e. the difficulty to set apart shear stress and lateral force. Static force test and sink test both prove that the instrument is precise, stable and applicable to the measurement of rough beds with different shear stresses.

关键词： direct method shear stress measurement

Determination of Amino Acids in Panax notoginseng by Microwave Hydrolysis and Derivatization Coupled with Capillary Zone Electrophoresis Detection

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Chemical Research in Chinese Universities 2013年第3期29卷 434-438页

作者： LI Xiao-tian ZHAO Ya-jing JIANG Cheng-fei ZHANG Han-qi YU Ai-min College of Chemistry Jilin University Changehun 130012 P. R. China

The microwave hydrolysis and derivatization coupled with capillary electrophoresis detection were developed for the separation and determination of the amino acids in Panax notoginseng. The experimental conditions for the microwave hydrolysis and derivatization were examined and optimized. Several parameters of capillary electrophoresis, such as pH value of background electrolyte, borate concentration and applied voltage were optimized Under the selected conditions, 11 amino acids were completely separated. The real sample was analyzed and the results were satisfactory. Compared with that of conventional heat hydrolysis and derivatization, the analytical time of this method was significantly shortened.

关键词： Microwave hydrolysis Derivatization Amino acid Capillary electrophoresis Panax notoginseng 2,4-Dinitrofluorobenene

Alignment of the photoelectron spectroscopy beamline at NSRL

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Chinese Physics C 2013年第11期37卷 104-107页

作者：李朝阳潘海斌魏珅潘从元安宁杜学维朱俊发王秋平 national Synchrotron Radiation Laboratory (NSRL) University of Science & Technology of China

Tile photoelectron spectroscopy beamline at national Synchrotron Radiation Laboratory （NSRL） is equipped with a spherical grating monochromator with the included angle of 174. Three gratings with line density of 200, 700 and 1200 lines/mm are used to cover the energy region from 60 eV to 1000 eV. After several years＇ operation, the spectral resolution and flux throughput were deteriorated, and realignment was necessary to improve the performance. First, the wavelength scanning mechanism, the optical components position and the exit slit guide direction are aligned according to tile design value. Second, the gratings are checked by Atomic Force Microscopy （AFM） and then the gas absorption spectrum is measured to optimize the focusing condition of the monoehromator. The spectral resolving power E/AE is recovered to the designed value of 1000@244 eV. The flux at the end station for the 200 lines/ram grating is about 1010 photons/sec/200 mA, which is in accordance with the design. The photon flux for the 700 lines/mm grating is about 5 108 photons/sec/200mA, which is lower than expected. This poor flux throughput may be caused by carbon contamination on the optical components. The 1200 lines/ram grating has roughness much higher than expected so the diffraction efficiency is too low to detect any signal. A new grating would be ordered. After the alignment, the beamline has significant performance improvements in both the resolving power aim the flux throughput for 200 and 700 lines/ram gratings and is provided to users.

关键词： synchrotron radiation, beamline alignment, photon flux, spectral resolution