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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

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

Optimizing the cleanliness in multi-segment disk amplifiers based on vector flow schemes

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High Power Laser Science and Engineering 2018年第1期6卷 1-6页

作者： Zhiyuan Ren jianqiang zhu Zhigang Liu Xiaowei Yang Key Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800 China

The objective of maintaining the cleanliness of the multi-segment disk amplifier in Shenguang-II(SG-II) is to reduce laser-induced damage for optics. The flow field of clean gas, which is used for the transportation of contaminant particles,is a key factor affecting the cleanliness level in the multi-segment disk amplifier. We developed a gas–solid coupling and three-dimensional flow numerical simulation model. The three-dimensional and two-phase flow model is verified by the flow-field smog experiment and the particle concentration measurement experiment with the 130-disk amplifier in SG-II. By optimizing the boundary conditions with the same flow rate, the multi-inlet vector flow scheme can not only effectively reduce the purging time, but also prevent the reverse diffusion of contaminant particles in the multi-segment disk amplifier and the deposition of contaminant particles on the surface of the Nd:glass.

关键词： cleanliness computational fluid dynamics flow field multi-segment disk amplifier vector flow

Stimulated Raman scattering in a non-eigenmode regime

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High Power Laser Science and Engineering 2020年第2期8卷 80-87页

作者： Yao Zhao Suming Weng Zhengming Sheng jianqiang zhu Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Key Laboratory for Laser Plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong UniversityShanghai 200240China SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUK

Stimulated Raman scattering(SRS)in plasma in a non-eigenmode regime is studied theoretically and *** from normal SRS with the eigen electrostatic mode excited,the non-eigenmode SRS is developed at plasma density ne>0.25nc when the laser amplitude is larger than a certain *** satisfy the phase-matching conditions of frequency and wavenumber,the excited electrostatic mode has a constant frequency around half of the incident light frequency ω0/2,which is no longer the eigenmode of electron plasma wave ω*** the scattered light and the electrostatic wave are trapped in plasma with their group velocities being ***-hot electrons are produced by the non-eigen electrostatic *** theoretical model is validated by particle-in-cell *** SRS driven in this non-eigenmode regime is an important laser energy loss mechanism in the laser plasma interactions as long as the laser intensity is higher than 10^15 W/cm^2.

关键词： hot electrons laser plasma interactions stimulated Raman scattering

Mechanistic study of continuous polishing

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High Power Laser Science and Engineering 2015年第2期3卷 1-7页

作者： Xiang Jiao jianqiang zhu Quantang Fan Yangshuai Li Key Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences University of Chinese Academy of Sciences

To establish the mechanism of surface change in a continuous polishing system, an ideal mathematical model is built based on Winkler's hypothesis and the Preston equation. The basic features of the model are the change rates in the surface peak–valley(PV) values of the workpiece, conditioning disk and pitch lap, rather than the specific surface shapes. In addition, an equilibrium state exists in the system, indicating that the surface change rates are all zero. Under equilibrium, the surface of the lap could remain flat, and it is insensitive to the surface error of the workpiece. These characteristics lay the theoretical foundations for high-efficiency and high-precision polishing. The methods to obtain an equilibrium state with flat surfaces are then proposed and confirmed experimentally. High-precision surfaces better thanλ/10(λ = 632.8 nm) are consistently produced experimentally.

关键词： continuous polishing equilibrium state high accura

DESIGN AND CONTROL OF AN ULTRAPRECISION STAGE USED IN GRATING TILING

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Chinese Journal of Mechanical Engineering 2007年第1期20卷 1-4页

作者： WANG Yong LIU Zhigang BO Feng zhu jianqiang Shanghai Institule of Optics and Fine Mechanics Chinese Acadamy of SciencssShanghai 201800China

In petawatt laser system, the *** to compose pulse compressor are very large in size which can be only acquired currently by arraying small aperture gratings to form a large one instead, an approach referred to as grating tiling. Theory and experiments have demonstrated that the coherent addition of multiple small gratings to form a larger grating is viable, the key technology of which is to control the relative position and orientation of each grating with high precision. According to the turin factors that affect the performance of the grating tiling, a 5-DOF ultraprecision stage is developed for the grating tiling experiment. The mechanism is formed by serial structures. The motion of the mechanism is guided by flexure hinges and driven by piezoelectric actuators and the movement resolution of which can achieve nanometer level. To keep the stability of the mechanism, capacitive position sensors with nanometer accuracy are fixed on it to provide feedback signlas with which to realize closed-loop control, thus the *** of the mechanism is within several nanometers range through voltage control and digital PID algorithm. Results of experiments indicate that the performance of the mechanism can meet the requirement of precision for grating tiling.

关键词： Grating compressor Orating filing Flexure mechanism Piezoelectric actuator

Effects of side subsurface defects induced by CNC machine on the gain spatial distribution in neodymium phosphate glass

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High Power Laser Science and Engineering 2016年第1期4卷 58-62页

作者： Bingyan Wang Junyong Zhang Shuang Shi Kewei You jianqiang zhu Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences

The processing method applied to the side surface is different from the method applied to the light pass surface in neodymium phosphate glass(Nd:glass), and thus subsurface defects remain after processing. The subsurface defects in the side surface influence the gain uniformity of Nd:glass, which is a key factor to evaluate the performance of amplifiers. The scattering characteristics of side subsurface defects were simulated by finite difference time domain(FDTD) Solutions software. The scattering powers of the glass fabricated by a computer numerical control(CNC)machine without cladding were tested at different incident angles. The trend of the curve was similar to the simulated result, while the smallest point was different with the complex true morphology. The simulation showed that the equivalent residual reflectivity of the cladding glass can be more than 0.1% when the number of defects in a single gridding is greater than 50.

关键词： cladding FDTD gain uniformity subsurface defect

A micromechanical bridge-shaped voltage-controlled oscillator

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Science China(Technological Sciences) 2004年第1期47卷 26-32页

作者： HAN jianqiang zhu Changchun ZHAO Hongpo LIU Junhua SHAO Jun Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China Xi'an Jiaotong University Xi'an 710049 China

A novel micromechanical bridge-shaped voltage-controlled oscillator with high Q value was fabricated. The core of this kind of oscillators is an electrothermally excited and piezoresistively detected micromechanical bridge resonator. Its resonance frequency can be adjusted by changing the DC voltage applied to the Wheatstone bridge. Theoretical analysis and experimental data show that its resonance frequency is linear with the square of the DC voltage. The linearity is better than 0.16% and the adjustable frequency range excels 17.15%.

关键词： voltage-controlled oscillator, microbridge, resonator, MEMS.

Review of special issue on high power facility and technical development at the NLHPLP

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High Power Laser Science and Engineering 2019年第1期7卷 90-91页

作者： jianqiang zhu National Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences

Achieving ignition of ICF(inertial confinement fusion)has been the great dream that scientists all over the world *** a grand challenge,this aim requires energetic and high quality *** power laser facilities,for this purpose,have therefore flourished over the past several *** high power laser facilities,also essential for high-energy-density(HED)scientific research and astrophysics,drive rapid progress of material science,electronics,precision machinery and so *** countries have successfully established a succession of facilities to study ICF and HED physics,such as National Ignition Facility(NIF)[1]in the United States and the Laser Megajoule(LMJ)in France[2].

关键词： ICF(inertial confinement fusion) high-energy-density(HED) Laser Megajoule(LMJ)