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Imaging Transparent Objects in a Turbid Medium Using a Femtosecond Optical Kerr Gate

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Chinese Physics Letters 2017年第10期34卷 49-51页

作者： Yi-Peng Zheng Jin-Hai Si Wen-Jiang Tan Xiao-Jing Liu jun-Yi tong Xun Hou Key Laboratory for Physical Electronics and Devices of the Ministry of Education of China and Shaanxi Key Lab of Information Photonic Technique School of Electronics and Information Engineering Xi＇an Jiaotong University Xi＇an 710049 Departments of Applied Physics Xi＇an University of Technology Xi＇an 710049

A femtosecond optical Kerr gate time-gated ballistic imaging method is demonstrated to image a transparent object in a turbid medium. The shape features of the object are obtained by time-resolved selection of the ballistic photons with different optical path lengths, the thickness distribution of the object is mapped, and the maximum is less than 3.6%. This time-resolved ballistic imaging has potential applications in studying properties of the liquid core in the near field of the fuel spray.

关键词： Imaging Transparent Objects in a Turbid Medium Using a Femtosecond Optical Kerr Gate

Characteristic fractional step finite difference method for nonlinear section coupled system

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Applied Mathematics and Mechanics(English Edition) 2014年第10期35卷 1311-1330页

作者：袁益让李长峰孙同军刘允欣 Institute of Mathematics Shandong University School of Economics Shandong University

For the section coupled system of multilayer dynamics of fluids in porous media, a parallel scheme modified by the characteristic finite difference fractional steps is proposed for a complete point set consisting of coarse and fine partitions. Some tech- niques, such as calculus of variations, energy method, twofold-quadratic interpolation of product type, multiplicative commutation law of difference operators, decomposition of high order difference operators, and prior estimates, are used in theoretical analysis. Optimal order estimates in 12 norm are derived to show accuracy of the second order approximation solutions. These methods have been used to simulate the problems of migration-accumulation of oil resources.

关键词： three-dimensional section coupled system complete nonlinear equation,characteristic fractional step convergence numerical simulation

Hyperbranched Poly(α-aminonitrile)s Constructed via Catalyst-Free Multicomponent Polymerization of Trialdehydes, Diamines and Trimethylsilyl Cyanide

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CHINESE JOURNAL OF POLYMER SCIENCE 2025年第2期43卷 341-349页

作者： Cheng, Tian-Yu Ding, Jian-Qing tong, Yu-Xin Fang, jun-Guo Wang, Jia Anhui Polytech Univ Sch Chem & Environm Engn Wuhu 241000 Peoples R China Songshan Lake Mat Lab Dongguan 523808 Peoples R China

Functional hyperbranched polymers, as an important class of materials, are widely applied in diverse areas. Therefore, the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance. In this work, trialdehydes, diamines, and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions, producing hyperbranched poly(alpha-aminonitrile)s with high molecular weights (Mw up to 4.87x104) in good yields (up to 85%). The hyperbranched poly(alpha-aminonitrile)s have good solubility in commonly used organic solvents, high thermal stability as well as morphological stability. Furthermore, due to the numerous aldehyde groups in their branched chains, these hb-poly(alpha-aminonitrile)s can undergo one-pot, two-step, four-component post-polymerization with high efficiency. This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes, amines and trimethylsilyl cyanide, but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.

关键词： Catalyst-free Multicomponent polymerization Hyperbranched polymer Post-polymerization

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某大跨转换桁架高层钢结构设计

建筑钢结构进展 2020年第4期22卷 103-109页

作者：童骏华建集团华东建筑设计研究总院上海200002

阐述了上海某大跨转换桁架高层钢结构设计思路。根据该工程的体型特点,对比了多种不同的转换结构方案,综合考虑各种因素最终选择“下托式”的主、次桁架转换方案。计算结果表明,采用该方案的结构整体指标满足规范要求,具有足够的抗侧刚... 详细信息

阐述了上海某大跨转换桁架高层钢结构设计思路。根据该工程的体型特点,对比了多种不同的转换结构方案,综合考虑各种因素最终选择“下托式”的主、次桁架转换方案。计算结果表明,采用该方案的结构整体指标满足规范要求,具有足够的抗侧刚度。在转换桁架设计中考虑了次框架的空腹桁架效应、活荷载不利布置和抗连续倒塌等因素影响;对转换层的楼板应力及转换桁架钢结构关键节点进行了有限元分析,并提出了相应的加强措施;通过施工模拟分析评估了施工顺序对整体结构的影响。该项目的设计过程及方法可为类似项目提供参考。

关键词：大跨度转换桁架高层建筑钢框架支撑结构空腹桁架效应节点有限元分析加强措施施工顺序模拟

A new design method for the transition region of the valve plate for an axial piston pump

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2015年第3期16卷 229-240页

作者： Bing XU Ying-hui SUN jun-hui ZHANG tong SUN Ze-bingMAO State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The optimization of the valve plate transition region is an important way of reducing the noise emission for an axial piston pump. However, the optimized methods through simulation or experiment are actually trial and error, and they cannot indicate the precise structural parameters of the valve plate transition region. In this study, a new design method for the transition region of valve plate based on the matching of flow area and reduction of transient reverse flow was proposed, and with which a valve plate was designed. Then, the impact of the flow ripple in the discharge line of an axial piston pump and the pressure overshoot and undershoot in the piston chamber on hydraulic and structural noise for axial piston pump is discussed. The noise reduction effect of the axial piston pump with this valve plate was analyzed by adopting a flow characteristic simulation model. Finally, the results showed that the application of this design method could contribute much to the reduction of the flow ripple and elimination of the pressure overshoot and undershoot. As a consequence, the method can be used in the design of a low-noise open circuit axial piston pump.

关键词： Axial piston pump Valve plate Flow ripple Pressure overshoot

China's Petrochemical Industry Enters E-business Era

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China Oil & Gas 2001年第3期8卷 44-47页

作者： Wang Chuanjie Wei tong jun

Global petrochemical industrial reform has been characterized with merging and reorganization in the past two years.

关键词： mode In China’s Petrochemical Industry Enters E-business Era www

Effect of low-dose radiation on thyroid function and the gut microbiota

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World Journal of Gastroenterology 2022年第38期28卷 5557-5572页

作者： jun-Yu tong Wen Jiang Xia-Qing Yu Ru Wang Gang-Hua Lu Ding-Wei Gao Zhong-Wei Lv Dan Li Nuclear Medicine Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200072China Department of Nuclear Medicine Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 200072Guangdong ProvinceChina

BACKGROUND The thyroid-gut axis has a great influence on the maintenance of human health;however,we know very little about the effects of low-dose ionizing radiation(LDR) on thyroid hormone levels and gut microbiota *** To investigate the potential effects of low-dose X-ray radiation to male C57BL/6J *** Peripheral blood was collected for enzyme-linked immunosorbent assay(ELISA),and stool samples were taken for 16S ribosomal RNA(rRNA) gene sequencing after *** We found that LDR caused changes in thyroid stimulating hormone(TSH) levels in the irradiated mice,suggesting a dose-dependent response in thyroid function to ionizing *** changes in the diversity and richness of the gut microbiota were observed in the LDR-exposed group in comparison to the *** abundance of Moraxellaceae and Enterobacteriaceae decreased in the LDR-exposed groups compared with the controls,and the Lachnospiraceae abundance increased in a dose-dependent manner in the radiated *** the abundances of uncultured_bacterium_g_Acinetobacter,uncultured_bacterium_o_Mollicutes_RF39,uncultured_bacterium_g_Citrobacter,and uncultured_bacterium_g_Lactococcus decreased in the radiated groups at the genus level,which showed a correlation with radiation exposure and diagnostic *** of functional metabolic pathways revealed that biological metabolism was predicted to have an effect on functional activities,such as nucleotide metabolism,carbohydrate metabolism,and glycan biosynthesis and ***,Kyoto Encyclopedia of Genes and Genomes pathway annotation also suggested that changes in the gut microbiota were related to processing functions,including translation,replication and *** LDR can change thyroid function and the gut microbiota,and changes in the abundances of bacteria are correlated with the radiation dose.

关键词： Low-dose ionizing radiation Thyroid Gut microbiota Thyroid-gut axis

Optical Measurement System for Motion Characterization of Surface Mount Technology

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Semiconductor Photonics and Technology 2006年第3期12卷 173-177,210页

作者： LI Song AN Bing ZHANG tong-jun XIE Yong-jun State Key Laboratory of Plastic Forming Simulation and Die ＆ Mould Technology Institute of Microsystem Huazhong University of Science and Technology Wuhan 430074 CHN

Advanced testing methods for the dynamics of mechanical microdevices are necessary to develop reliable, marketable microelectromechanical systems. A system for measuring the nanometer motions of microscopic structures has been demonstrated. Stop-action images of a target have been obtained with computer microvision, microscopic interferometry, and stroboscopic illuminator. It can be developed for measuring the in-plane-rigid-body motions, surface shapes, out-of-plane motions and deformations of microstructures. A new algorithm of sub-pixel step length correlation template matching is proposed to extract the in-plane displacement from vision images. Hariharan five-step phase-shift interferometry algorithm and unwrapping algorithms are adopted to measure the out-of-plane motions. It is demonstrated that the system can measure the motions of solder wetting in surface mount technology(SMT).

关键词： Interferometry Stroboscopic imaging Computer microvision Dynamic measurement MEMS reliability Solder wetting

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反求工程中融合特征捕捉的光学三维测量方法

光电工程 2005年第2期32卷 19-22页

作者：姜涛习俊通严隽琪上海交通大学CIM所上海200030

特征在反求工程实体建模中具有重要的作用,在三维测量过程中实现特征捕捉,可保证实体建模的精度和效率。提出了基于格雷码投影的融合特征捕捉的光学三维测量方法,在测量过程中采集一幅无光栅图像,通过无光栅图像的边界检测与格雷码特征... 详细信息

特征在反求工程实体建模中具有重要的作用,在三维测量过程中实现特征捕捉,可保证实体建模的精度和效率。提出了基于格雷码投影的融合特征捕捉的光学三维测量方法,在测量过程中采集一幅无光栅图像,通过无光栅图像的边界检测与格雷码特征提取相结合,实现了三维测量与特征捕捉的融合。对典型工业零件进行了实验,在测量过程中实现特征的有效捕捉,保证了特征的识别和精确提取,测量效果良好,分辨力达到了 0.1mm。该方法在反求工程中具有一定的实用价值。

关键词：反求工程特征捕捉三维测量格雷码