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High Power Laser Science and Engineering 2024年第3期12卷 84-89页

作者： Ruifeng Wang Xiaoqi Zhang Yanli Zhang Fanglun Yang Jianhao Tang Ziang Chen jianqiang zhu Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

Based on the paraxial wave equation,this study extends the theory of small-scale self-focusing(SSSF)from coherent beams to spatially partially coherent beams(PCBs)and derives a general theoretical equation that reveals the underlying physics of the reduction in the B-integral of spatially *** the analysis of the simulations,the formula for the modulational instability(MI)gain coefficient of the SSSF of spatially PCBs is obtained by introducing a decrease factor into the formula of the MI gain coefficient of the SSSF of coherent *** decrease can be equated to a drop in the injected light intensity or an increase in the critical *** to this formula,the reference value of the spatial coherence of spatially PCBs is given,offering guidance to overcome the output power limitation of the high-power laser driver due to SSSF.

关键词： B-integral complex screen method nonlinearity small-scale self-focusing spatially partially coherent beams

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旱涝急转对玉米叶片衰老特性和产量的影响

农业工程学报 2024年第5期40卷 141-147页

作者：漆栋良朱建强浙江水利水电学院水利与环境工程学院杭州310000 长江大学农学院荆州434025

为研究旱涝急转对玉米叶片衰老特性和产量的影响,以春玉米“宜丹629”为供试材料,2021年在测坑条件下,设置拔节期旱(drought,D)、涝(waterlogging,W)、旱急转轻涝(drought-light waterlogging,D-LW)、旱急转中涝(drought-moderate waterlogging,D-MW)、旱急转重涝(drought-heave waterlogging,D-HW)、和正常供水(control,CK)6个处理。测定不同处理组合下玉米大喇叭口期、抽雄期和灌浆期叶片叶绿素仪(soil and plant analyzer development,SPAD)值、过氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)、过氧化氢酶(catalase,CAT)活性、丙二醛(malondialdehyde,MDA)、可溶性蛋白含量和净光合速率(net photosynthetic rate,P_(n)),成熟期籽粒产量及其构成。结果表明,与CK相比,D-LW处理抽雄期和灌浆期玉米叶片的SPAD值、SOD、POD、CAT活性、可溶性蛋白含量、P_(n)和成熟期穗数、穗粒数和千粒质量差异不显著,其籽粒产量维持在较高水平(7 810.3kg/hm~2),说明旱急转轻涝不会加速玉米叶片的衰老,从而稳定籽粒产量。而其他水分胁迫处理显著降低各监测时期玉米叶片SPAD值、SOD、POD、CAT活性、可溶性蛋白含量和P_(n),明显提高MDA含量,使穗数、穗粒数和千粒质量减少,最终显著降低产量(较CK下降13.3%~72.7%)。整体上,D-MW和D-HW处理明显加速玉米叶片衰老,严重抑制籽粒产量。综上,拔节期旱后急转轻涝对玉米叶片SPAD值、抗氧化酶活性、可溶性蛋白含量和P_(n)有补偿作用,从而获得较高的籽粒产量。研究结果为玉米应对旱涝急转灾害和灌排管理提供理论依据。

关键词：产量光合作用旱涝急转抗氧化酶活性玉米

Linear mathematical model for the unique solution of 3D ptychographic iterative engine

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Chinese Optics Letters 2024年第5期22卷 1-7页

作者：吴丽青齐乃杰昌成成陶华何小亮刘诚朱健强 Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China National Laboratory on High Power Laser and Physics China Academy of Engineering PhysicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Diffraction intensities of the 3D ptychographic iterative engine(3PIE)were written as a set of linear equations of the selfcorrelations of Fourier components of all sample slices,and an effective computing method was developed to solve these linear equations for the transmission functions of all sample slices *** both theoretical analysis and numerical simulations,this study revealed the underlying physics and mathematics of 3PIE and demonstrated for the first time,to our knowledge,that 3PIE can generate mathematically unique reconstruction even with noisy data.

关键词： 3D imaging 3D ptychographic iterative engine linear equation group unique solution

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双波长大口径液晶光弹性测量仪研制

中国激光 2024年第13期51卷 133-142页

作者：陈昱志邢童璐林强刘诚朱健强中国科学院上海光学精密机械研究所高功率激光物理联合实验室上海201800 中国科学院大学北京100049

提出了一种基于双波长椭圆偏振光测量光弹性应力的方法,采集两种相近波长照明下、特殊液晶旋光角度下透过待测样品的光强分布图像,对其进行一系列计算处理,得到待测样品的应力分布。利用双波长LED和液晶旋光板等先进光源和先进光调控器... 详细信息

提出了一种基于双波长椭圆偏振光测量光弹性应力的方法,采集两种相近波长照明下、特殊液晶旋光角度下透过待测样品的光强分布图像,对其进行一系列计算处理,得到待测样品的应力分布。利用双波长LED和液晶旋光板等先进光源和先进光调控器件,发明了一个可以测量样品中应力分布的光学仪器。进行了相关的实验测量,并与传统的六步相移方法做了实验对比验证了该方法的有效性,相对误差达到2.85%。且所研究的光弹性液晶测量仪结构简单、操作快速,不需要复杂的机械旋转等手动调控。仪器分辨率达到0.25 mm,符合光弹性测量标准。

关键词：光弹性测量应力液晶椭圆偏振光

基于等强度悬臂梁的低频高灵敏度FBG加速度传感器研究

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光电子．激光 2024年第2期35卷 113-121页

作者：覃荷瑛李纯德祝健强罗伯光桂林理工大学广西岩土力学与工程重点实验室广西桂林541004 桂林理工大学土木工程学院广西桂林541004

针对桥梁低频振动监测灵敏度低的问题,提出了一种基于等强度悬臂梁的低频高灵敏度光纤光栅(fiber Bragg grating, FBG)加速度传感器。以悬臂梁厚度与质量块质量为主要参数设计了12组FBG加速度传感器,通过激振器对传感器进行幅频特性、... 详细信息

针对桥梁低频振动监测灵敏度低的问题,提出了一种基于等强度悬臂梁的低频高灵敏度光纤光栅(fiber Bragg grating, FBG)加速度传感器。以悬臂梁厚度与质量块质量为主要参数设计了12组FBG加速度传感器,通过激振器对传感器进行幅频特性、灵敏度及横向抗干扰试验,得到较适合监测桥梁振动的一组传感器,其固有频率为49 Hz,工作频带为0—34 Hz,灵敏度高达664.53 pm/g,线性度为99.9%,且横向抗干扰能力强。通过理论推导到试验验证,为桥梁振动提供一种新型有效的监测手段。

关键词：等强度悬臂梁光纤光栅(FBG) 加速度传感器桥梁监测

高功率激光系统中调制光束的复杂非线性传输效应

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中国激光 2024年第11期51卷 131-142页

作者：刘雨欣焦兆阳王宏昌孙明营朱健强中国科学院上海光学精密机械研究所高功率激光物理联合实验室上海201800 中国科学院大学材料与光电研究中心北京100049

非线性光场增强是导致高功率激光装置终端光学元件损伤的主要原因之一。系统地研究单缺陷的精细形貌以及双缺陷的三维空间分布对调制光束的非线性演变规律的影响,发现了多种非线性传输新现象并揭示了其产生机制。仿真结果表明:边缘陡峭... 详细信息

非线性光场增强是导致高功率激光装置终端光学元件损伤的主要原因之一。系统地研究单缺陷的精细形貌以及双缺陷的三维空间分布对调制光束的非线性演变规律的影响,发现了多种非线性传输新现象并揭示了其产生机制。仿真结果表明:边缘陡峭的单一缺陷会产生双峰热像,这打破了传统认知中缺陷和热像在纵向的共轭关系;双缺陷间的相互作用导致双缺陷中轴位置上额外热像峰的出现,打破了缺陷和热像在横向的一一对应关系。系列研究结果表明了调制光束非线性传输的复杂性,上游缺陷的精细形貌差别和相互干涉均可能使得下游产生额外的光场强区,强度得到进一步增强,最终导致基于原有关于B积分和热像认知的驱动器非线性控制策略失效。本研究结果加深了对复杂非线性光场传输规律的认知,不仅有助于优化装置中终端元件的排布,而且对高功率激光装置中大口径光学元件缺陷的精密检测和评估提出了新的要求,为高功率激光装置的终端负载能力提高提供了重要技术参考。

关键词：高功率激光驱动器非线性传输效应缺陷光场调制自聚焦

Exploring the formation potential and optical properties of secondary organic aerosol from the photooxidation of selected short aliphatic ethers

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Journal of Environmental Sciences 2020年第9期32卷 82-90页

作者： jianqiang zhu Jianlong Li Lin Du Environment Research Institute Shandong UniversityQingdao 266237China

Secondary organic aerosol(SOA)formation potential for six kinds of short aliphatic ethers has been *** size distribution,mass concentration,and yield of SOA formed by ethers photooxidation were determined under different *** results showed that all six ethers can generate SOA via reaction with OH radicals even under no seed and NOxfree *** mass concentration for six seedless experiments was less than 10μg/m3 and the SOA yields were all below 1%.The strong increase in the SOA formation was observed when the system contained ammonium sulfate seed particles,while SOA yield decreased under the high-NOx *** composition was analyzed using offline *** spectra indicated that there are complex components in the particle-phase including carbonyls acid and aldehydes ***,the aqueous filter extracts were analyzed using ultraviolet-visible spectrometer and fluorescence *** the fresh methyl n-butyl ether SOA,the largest absorption peak occurs at 280 nm and there exists slightly absorption in the 300-400 ***-emission matrices display the distinct peak at excitation/emission=470 nm/480 nm according to the fluorescence *** findings are important considerations of formation for ether SOA that can eventually be included in atmospheric models.

关键词： aerosol photooxidation potential

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2023年光学热点回眸

科技导报 2024年第14期42卷 5-37页

作者：谢兴龙李昕然童妙妍朱健强中国科学院上海光学精密机械研究所高功率激光物理联合实验室上海201800 中国科学院大学光电工程与材料科学中心北京100049

回顾了光学领域2023年的重大进展,盘点了光物理、光学材料和结构、生物和医疗光学、光与物质相互作用、光电子学、光学设计和仪器仪表、光学信息处理、光源与强场激光等研究领域的重要成果,探讨了其在未来可能会对人类生存及生活方式产... 详细信息

回顾了光学领域2023年的重大进展,盘点了光物理、光学材料和结构、生物和医疗光学、光与物质相互作用、光电子学、光学设计和仪器仪表、光学信息处理、光源与强场激光等研究领域的重要成果,探讨了其在未来可能会对人类生存及生活方式产生的积极影响。

关键词：光物理生物和医疗光学光电子学

Optimization of the transmitted wavefront for the infrared adaptive optics system

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Science China(Physics,Mechanics & Astronomy) 2014年第4期57卷 608-614页

作者： YANG PengQian HIPPLER Stefan zhu jianqiang Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Max-Planck-Institute for Astronomy Knigstuhl 17D-69117 Heidelberg Germany Graduate University of Chinese Academy of Sciences

The adaptive optics system for the second-generation Very Large Telescope-interferometer(VLTI)instrument GRAVITY consists of a novel cryogenic near-infrared wavefront sensor to be installed at each of the four unit telescopes of the Very Large Telescope(VLT).Feeding the GRAVITY wavefront sensor with light in the 1.4–2.4μm band,while suppressing laser light originating from the GRAVITY metrology system requires custom-built optical *** this paper,we present the development of a quantitative near-infraredpoint diffraction interferometric characterization technique,which allows measuring the transmitted wavefront error of the silicon entrance windows of the wavefront sensor *** technique can be readily applied to quantitative phase measurements in the near-infrared ***,by employing a slightly off-axis optical setup,the proposed method can optimize the required spatial resolution and enable real time measurement *** feasibility of the proposed setup is demonstrated,followed by a theoretical analysis and experimental *** experimental results show that the phase error repeatability in the nanometer regime can be achieved.

关键词： adaptive optics non-common aberration point diffraction interferometry

Radiation model of a xenon flash lamp in a laser amplifier pump cavity

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High Power Laser Science and Engineering 2015年第4期3卷 31-37页

作者： Yongzhong Wu jianqiang zhu Zhixiang Zhang Yangshuai Li National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences University of Chinese Academy of Sciences

Understanding the radiation model of a flash lamp is essential for the reflector design of a laser amplifier. Reflector design often involves several simplifying assumptions, like a point or Lambertian source; either of these assumptions may lead to significant errors in the output distribution. In practice, source non-idealities usually result in sacrificing the amplifier's gain coefficient. We propose a novel test technique for attaining the xenon flash lamp absolute spectral intensity at various angles of view, and then accurately predict radiation distributions and generate the reflector shape. It is shown that due to the absorption of emitted radiation by the lamp itself, the behavior of the radiation model at various wavelengths is different. Numerical results of xenon plasma absorption coefficient were compared with the measured data. A reasonable agreement was obtained for the absorption coefficient parameters. Thus, this work provides a useful analytical tool for the engineering design of laser amplifier reflectors using xenon flash lamps as pumps.

关键词： absorption coefficient current density radiation model xenon flash lamp xenon plasma