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Stable continuous-wave single-frequency intracavity frequency-doubled laser with intensity noise suppressed in audio frequency region

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Chinese Physics B 2019年第9期28卷 197-202页

作者： Ying-Hao Gao yuan-Ji Li Jin-Xia Feng Kuan-shou Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

We demonstrated a continuous wave(cw) single-frequency intracavity frequency-doubled Nd:YVO_4/LBO laser with 532 nm output of 7.5 W and 1.06 μm output of 3.1 W, and low intensity noise in audio frequency *** suppress the intensity noise of the high power 532 nm laser, a laser frequency locking system and a feedback loop based on a Mach-Zehnder interferometer were designed and *** influences of the frequency stabilization and the crucial parameters of the MZI, such as the power splitting ratio of the beam splitters and the locking state of the MZI, on the intensity noise of the 532 nm laser were investigated in *** the experimental optimizations, the laser intensity noise in the frequency region from 0.4 kHz to 10 kHz was significantly suppressed.

关键词： continuous wave single-frequency intracavity frequency-doubled laser noise suppression power stabilization audio frequency

Copper-catalyzed Ullmann-type synthesis of diaryl ethers assisted by salicylaldimine ligands

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Chinese Chemical Letters 2014年第2期25卷 337-340页

作者： Cun-Wei Qian Wen-Lin Lv Qian-shou Zong Mao-yuan Wang Dong Fang School of Chemistry and Chemical Engineering Yancheng Teachers University School of Biological and Chemical Engineering Jiaxing University

A series of salicylaldimine ligands were designed to promote the copper-catalyzed Ullmann cross- coupling reaction. After a screening process, 2-（（2-isopropylphenylimino）methyl）phenol was found to serve as a good supporting ligand for this reaction. Employing this Schiff-base ligand as a new supporting ligand, the copper-catalyzed coupling reactions of aryl bromides and aryl iodides with various phenols successfully proceeded in good yields under mild conditions. Various diaryl ethers were obtained with excellent yields in dioxane in the presence of K3P04 and a catalytic amount of copper（I） salt.

关键词： Copper catalyst Salicylaldimine ligands Ullmann coupling Diaryl ethers

The mini-QSO's contribution to cosmic reionization

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Research in Astronomy and Astrophysics 2010年第3期10卷 199-210页

作者： Ying-Ying Wang Lei Wang shou-Ping Xiang Yu Wang Jing-Meng Hao Ye-Fei yuan Center for Astrophysics University of Science and Technology of China Hefei 230026 China Shanghai Astronomical Observatory Joint Institute for Galaxy and Cosmology （JOINGC） of SHAO and USTC Shanghai 200030 China

By employing an improved simulation of the evolution of black holes （BHs） based on the merger tree of dark matter halos, we explore the relationship between the central BH mass Mbh and velocity dispersion σ＊ at high redshift z ≥ 6 and quantify the mini-QSO＇s （with BH mass M = 200 - 105M⊙） contribution to cosmic reionization. The simulation demonstrates how seed BHs migrate onto the MBH-σ＊ relation by merging with each other and accreting gas at z ≥ 6： 1. The correlation between BHs and their host halos increases as the BHs grow; 2. The slope, i.e. Ф = dlog（Mbh）/dlog（σ＊） in the relationship, is insensitive to the redshift at z 〉 6. In agreement with previous work, we find that mini-QSOs＇ ionizing capability to the Universe lies in the range - 25% - 50% if early miniquasars have extremely high duty cycles, i.e. P（z 〉 6） - 0.9 - 1.

关键词： cosmology: theory -- galaxies: evolution

Preparation and properties of poly HTBN-based urethane urea/organo reactive montmorillonite nanocomposites

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Frontiers of Materials Science 2012年第4期6卷 338-346页

作者： Zai-Feng LI yuan WU Fu-Tao ZHANG Yu-Yang CAO shou-Peng WU Ting WANG State Key Laboratory Base of Eco-chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Oil Production Institute of Shengli Oilfield Dongying 257001China

With ultrasonic assistant mixing way, an intercalated mixture of polyol/ organo reactive montmorillonite （ORMMT） was pretreated. The prepolymer composed MMT clay was prepared by reaction of polyol/ORMMT mixture with toluene diisocyanate （TDI）. The resultant prepolymer reacted with extender （DMTDA） and then the polyur- ethane-urealorgano reactive montmorillonite （PUUIORMMT） nanocomposites were obtained. The structure, morphology and properties of PUU/ORMMT nanocomposites were characterized by FT-IR, TEM, AFM, strain-stress machine, TGA, and dynamic mechanical analysis （DMA）. The results showed that when tl-m OMMT content is 3%, the PUU/ORMMT nanocomposities performed super mechanical properties. Because of the presence of ORMMT, both Tg of the soft segment and tan5 of the PUU increased, and the decomposition temperature for the first step and the second step increased respectively. TEM images showed that the organophilic MMT particles in the PUU composite exhibit a high degree of intercalation and exfoliation.

关键词： polyurethane-urea (PUU) organo-MMT morphology dynamic mechanicalanalysis (DMA) nanocomposite

High efficiency sub-nanosecond electro-optical Q-switched laser operating at kilohertz repetition frequency

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Chinese Physics B 2020年第8期29卷 286-291页

作者： Xin Zhao Zheng Song yuan-Ji Li Jin-Xia Feng Kuan-shou Zhang State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Based on a theoretical model of Q-switched laser with the influences of the driving signal sent to the Pockels cell and the doping concentration of the gain medium taken into account,a method of achieving high energy sub-nanosecond Q-switched lasers is proposed and verified in *** a Nd:YVO4 crystal with a doping concentration of 0.7 at.%is used as a gain medium and a driving signal with the optimal high-level voltage is applied to the Pockels cell,a stable single-transverse-mode electro-optical Q-switched laser with a pulse width of 0.77 ns and a pulse energy of 1.04 mJ operating at the pulse repetition frequency of 1 kHz is *** precise tuning of the pulse width is also demonstrated.

关键词： milijoule level sub-nanosecond laser kilohertz repetition frequency doping concentration of laser crystal tunable pulse width

Ischemic glans penis after circumcision

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Asian Journal of Andrology 2004年第2期6卷 161-163页

作者： yuan-ShengTzeng shou-HungTang EnMeng Teng-FuLin Guang-HuanSun DivisionofUrology DepartmentofSurgery DepartmentofUndersea＆HyperbaricMedicine Tri-ServiceGeneralHospitalNationalDefenseMedicalCenterTaipeiChina

A 33-year-old male receiving dorsal penile nerve block (DPNB) for circumcision exhibited a postoperative ischemic change over the glans penis. The event occurred nearly 24 hours after the procedure. The patient was treated with intravenous pentoxifyllin and hyperbaric oxygenation. Total reverse of the ischemia was observed. The complications associated with circumcision and DPNB were reviewed and discussed.

关键词： circumcision glans penis hyperbaric oxygenation

A NUMERICAL SIMULATION OF 3-D INNER FLOW IN UP-STREAM PUMPING MECHANICAL SEAL

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Journal of Hydrodynamics 2006年第5期18卷 572-577页

作者： ZHANG Jin-feng yuan shou-qi FU Yong-hong FANG Yu-jian Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China School of Mechanical Engineering Jiangsu University Zhenjiang 212013 China School of Energy and Environment Xihua University Chengdu 610039 China

Numerical simulation of 3-D inner flow between Up-stream Pumping Mechanical Face Seals （UPMFS） faces was initially done by CFD software, which made the flow visualization come true. Simulation results directly discover the action of hydrodynamic lubrication, and by comparison with that of Conventional Mechanic Face Seals （CMFS）, the advantage over bigger bearing capability, less friction and much less leakage are explained clearly. Otherwise there are also some different ideas and results from precedent analysis and computational research results： dynamic and static pressure profiles can be obtained respectively instead of the analytic total pressure distribution only, pressure distribution is nonlinear, while always be solved as linear, lower pressure is observed at the area of inner diameter caused by the grooves, but its possible cavitations effects to the performance of UPMFS still need further study.

关键词： Up-stream (UPMFS) Conventional hydrodynamic lubrication simulation Pumping Mechanical Face Seals Mechanic Face Seals (CMFS) visualization of flow numerical simulation

Design of a personnel safety interlock system for proton therapy

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Nuclear Science and Techniques 2021年第4期32卷 49-59页

作者： shou-yuan Wang Yun-Tao Song Han-Sheng Feng Shi Li Hai-Lin Cao Jing Zhang Ou-Wen Huang Zhu Li Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Hefei CAS Ion Medical and Technical Devices Co.Ltd Hefei 230088China

Proton therapy is the most advanced radiotherapy approach in the world,and causes less damage to normal human tissue than traditional *** the treatment process produces a high-energy proton beam,the personnel safety interlock system mainly considers measures to protect personnel from radiation hazards during beam preparation and the beam release *** other safety interlock systems,the personnel safety interlock system designed in this study focuses on the safety and stability of the system *** hardware and software of important interlock control loops are designed and developed according to the requirements of Safety Integrity Level 3 specified by IEC61508.A set of redundant ring networks was developed to ensure that damage to a certain network line does not affect the normal operation of the system.A set of friendly operation interfaces and data storage systems were developed to ensure that the operator can monitor the data in real time and trace the *** personnel safety interlock system mainly includes a beam enabling function,clearance function,and emergency stop *** system was put into actual use and successfully ensured personnel safety.

关键词： Personnel safety Radiation protection Interlock system Safety integrity levels

LAMOST CCD camera-control system based on RTS2

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Research in Astronomy and Astrophysics 2018年第5期18卷 69-82页

作者： yuan Tian Zheng Wang Jian Li Zi-Huang Cao Wei Dai shou-Lin Wei Yong-Heng Zhao Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of SciencesBeijing 100101 China Computer Technology Application Key Lab of Yunnan Province Kunming University of Science and TechnologyKunming 650500 China University of Chinese Academy of Sciences Beijing 100049 China

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST） is the largest existing spectroscopic survey telescope, having 32 scientific charge-coupled-device（CCD） cameras for acquiring spectra. Stability and automation of the camera-control software are essential, but cannot be provided by the existing system. The Remote Telescope System 2 nd Version（RTS2） is an open-source and automatic observatory-control system. However, all previous RTS2 applications were developed for small telescopes. This paper focuses on implementation of an RTS2-based camera-control system for the 32 CCDs of LAMOST. A virtual camera module inherited from the RTS2 camera module is built as a device component working on the RTS2 framework. To improve the controllability and robustness, a virtualized layer is designed using the master-slave software paradigm, and the virtual camera module is mapped to the 32 real cameras of LAMOST. The new system is deployed in the actual environment and experimentally tested. Finally, multiple observations are conducted using this new RTS2-frameworkbased control system. The new camera-control system is found to satisfy the requirements for automatic camera control in LAMOST. This is the first time that RTS2 has been applied to a large telescope, and provides a referential solution for full RTS2 introduction to the LAMOST observatory control system.

关键词： telescopes - techniques imaging spectroscopy - methods observational - instrumentation detectors