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Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2*)Shui-Cai WANG~2 Jun-Fang HE~2 Hui CHEN~3 1 institute of Photonics and Photo-Technology,Northwest University,xi'an 710069,china 2 State Key Laboratory of Transient optics and Photonics,xi 'an institute of optics and precision mechanics,chinese academy of sciences,xi'an 710068.china 3 Laboratoty of Photosynthesis Basic Research,institute of Botany,chinese academy of sciences,Beijing 100093,china institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State Key Laboratory of Transient optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China Laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb628,Chlb646,Chlb652654,657,Chla664666,Chla674677.680and Chla682683were discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 628 nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652654,657,Chla664666,Chla674677.680and Chla682683were determined to be 1.44ns,1.43 ns,636 ps and 713 ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

Experimental study on high power all-fiber laser

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chinese optics Letters 2010年第4期8卷 404-406页

作者：赵保银段开椋赵卫李成王屹山 State Key Laboratory of Transient optics and Photonics xi'an institute of optics and precision mechanics Chinese Academy of Sciences Graduate University of chinese academy of sciences

A high power all-fiber laser is experimentally studied.A monolithic fiber laser system with only one stage of resonator cavity is constructed and 404-W continuous wave（CW） output power is *** opticalto -optical conversion efficiency is up to 64%.The laser central wavelength is at 1081 nm with the spectral full-width at half-maximum（FWHM） of 2 *** laser setup can work with excellent stability;in the long time of high power operation,no thermal distortions or damages are observed.

关键词： Conversion efficiency

Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3,ZHANG FuChun3,ZHANG ZhiYong4,LU ShuYuan5 & YANG YanNing3 1 xi’an institute of optics and precision mechanics,chinese academy of sciences,xi’an 710068,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3 College of Physics and Electronic Information,Yan’an University,Yan’an 716000,china 4 Information Science and Technology Institution,Northwest University,xi’an 710127,china 5 Department of Telecommunications,xi’an institute of Posts and Telecommunications,xi’an 710121,china xi’an institute of optics and precision mechanics Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of sciences Beijing China College of Physics and Electronic Information Yan’an University Yan’an China Information Science and Technology Institution Northwest University Xi’an China Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3p electron spins and Fe 3d electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3d electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

Preparations on Several GRIN Lenses

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光学学报 2003年第S1期23卷 23-24页

作者： Li Yulin, Wang Weiping, Zhang xiangdong, Huo Junmin (xi’an institute of optics & precision mechanics, The chinese academy of sciences xi抋n institute of optics & precision mechanics The Chinese Academy of Sciences

Gradient index materials have been developed from glass melting process to GRIN lenses. Two kinds of GRIN lenses have been fabricated by ion-exchange and glass fusion/diffusion. The main applications to GRIN lenses ar... 详细信息

关键词： have GR of in been Preparations on Several GRIN Lenses on

Studies　on　Passive　Mode－Locking　Characteristics　of　Nd：YAG　Laser　With　a　Nonlinear　Coupled－Cavity

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chinese Journal of Lasers 1995年第1期B4卷 19-24页

作者： CHENG Zhao XU Dalun(State Key Laboratory of Transient optics and Technology,xi an institute of optics and precision mechanics,Academia Sinica,xi,an 710068, china) xi'an Inst of optics and precision Mechanics Xi'an China

ＳｔｕｄｉｅｓｏｎＰａｓｓｉｖｅＭｏｄｅ－ＬｏｃｋｉｎｇＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＮｄ：ＹＡＧＬａｓｅｒＷｉｔｈａＮｏｎｌｉｎｅａｒＣｏｕｐｌｅｄ－ＣａｖｉｔｙＳｔｕｄｉｅｓｏｎＰａｓｓｉｖｅＭｏｄｅ－Ｌｏｃ... 详细信息

ＳｔｕｄｉｅｓｏｎＰａｓｓｉｖｅＭｏｄｅ－ＬｏｃｋｉｎｇＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＮｄ：ＹＡＧＬａｓｅｒＷｉｔｈａＮｏｎｌｉｎｅａｒＣｏｕｐｌｅｄ－ＣａｖｉｔｙＳｔｕｄｉｅｓｏｎＰａｓｓｉｖｅＭｏｄｅ－ＬｏｃｋｉｎｇＣｈａｒａｃｔｅｒｉｓｔｉ...

关键词： Coupled-cavity mode locking resonant passive mode-locking high-repetition-rate laser

CALCULATION FOR DEFORMATION OF THE FLExiBLE GUIDE ON precision MICROPOSITIONER

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chinese Journal of Mechanical Engineering 1999年第4期12卷 266-269页

作者： Zhou Mingbao institute of optics and Electronics, chinese academy of sciences chinese Acad of sciences China

The equations for calculating the deformation of parallelogram type flexible guide, which is caused by the external force, are derived. The correctness of these equations is verified by comparison with other research ... 详细信息

关键词： Flexible guide Elastic deformation

Fabrication of sub-micro size PZT array and their ferroelectric properties

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Science china(Technological sciences) 2006年第6期49卷 693-700页

作者： ZHAO Gaoyang1, ZHANG Weihua1, XU Guomin1, DENG xiaocui1, JIANG Bailing1 & ZHAO Wei2 1. School of Materials Science and Engineering, xi’an University of Technology, xi’an 710048, china 2. xi’an institute of optics and precision mechanics of CAS, xi’an 710048, china School of Materials Science and Engineering Xi’an University of Technology Xi’an China xi’an institute of optics and precision mechanics of CAS Xi’an China

The photosensitive PZT sols and their gel films were prepared by sol-gel process. Based on the photosensitivity of the PZT gel films, two-dimensional (2D) array of the PZT gel film was fabricated using twice-exposure of double-beam interference on the gel film. PZT gel films coated on ITO/quartz substrate were exposed to an interference fringe of 325 He-Cd laser beams, the substrate was rotated by 90° between the first and second irradiation steps. Island type periodic 2D array structures with a pitch of 1 μm and cell size of about 480 nm × 480 nm × 40 nm were formed after the irradiation, and followed by leaching with organic solvent, and then by heat treatment at 600°C for 15 min. The hysteresis loops of the cell in PZT array were in-situ measured by the online-operation of TF analyzer and atomic force microscope (AFM). The probe can be located on the locked cell of PZT array in the AFM image. The alternating voltage applied to the locked cell is supplied by the TF analyzer through the conductive coating probe, and then the test signal is fed back to the TF analyzer to obtain the hysteresis loop of the locked cell of array in the absence of top electrode. The results show that the sub-micro size PZT arrays prepared in this way are of polarization reversal characteristics with the alternating electric fields, thereby exhibiting obvious ferroelectricity.

关键词： PZT, ferroelectric films, photosensitivity, hysteresis loop.

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-xi Wan xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of chinese academy of sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Primary scientific results of Chang'E-1 lunar mission

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Science china Earth sciences 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2, LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5, WANG HuanYu6, ZHANG xiaoHui7, WANG ShiJin7, WANG Min1, REN xin1, MU LingLi1, KONG DeQing1, WANG xiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU xinYing1, ZHENG YongChun1, LI JunDuo1, ZOU xiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china 2 institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3.xi’an institute of optics and precision mechanics, chinese academy of sciences, xi’an 710119, china 4 Shanghai institute of Technical Physics, chinese academy of sciences, Shanghai 200083, china 5 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 6 institute of High Energy Physics, chinese academy of sciences, Beijing 100049, china 7 Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190, china National Astronomical Observatories Chinese Academy of Sciences Beijing China institute of Geochemistry Chinese Academy of Sciences Guiyang China xi’an institute of optics and precision mechanics Chinese Academy of Sciences Xi’an China Shanghai institute of Technical Physics Chinese Academy of Sciences Shanghai China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China institute of High Energy Physics Chinese Academy of Sciences Beijing China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results