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

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 Chlb62.,Chlb646,Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83were discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 62. 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 Chlb652.54,657,Chla664666,Chla674677.680and Chla682.83were 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

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Comparison of energy structure and spectral properties of Ce:LaAlO_3 and Ce:Lu_2.SiO_4)O

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Science china(Technological sciences) 2009年第12期52卷 3678-3682页

作者： WANG XiaoDan 1 ,PAN Tao 1 ,ZANG TaoCheng 1 ,LI JianKang 1 ,ZHAO ZhiWei 2.,ZHANG LianHan 2.&XU Jun3 1Department of Applied physics,University of Science and Technology of Suzhou,Suzhou 2.5009,china 2.hanghai {2. of Optics and Fine Mechanics,chinese academy of sciences,Shanghai 2.1800,china 3Shanghai {2. of Ceramics,chinese academy of sciences,Shanghai 2.1800,china 1. Department of Applied physics University of Science and Technology of Suzhou Suzhou 215009 China 2. Shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 3. Shanghai institute of Ceramics Chinese Academy of Sciences Shanghai 201800 China

Undoped LaAlO3 and 1 at.%Ce:LaAlO3 single crystals were grown by the Czochralski *** and fluorescence spectra were measured at room *** energy levels structure of Ce:LaAlO3 was *** this paper,two viewpoints were *** first one is:the energy levels structure of Ce:LaAlO3 is very similar to that of Ce:Lu2.SiO4)O which is a well-known *** the energy levels structure of Ce:LaAlO3 and Ce:Lu2.SiO4)O,the lowest 5d energy level of Ce 3+ is located below the bottom of the conduction band of host crystal and the other higher 5d energy levels of Ce 3+ are located above the bottom of the conduction band of host *** second one is:Ce:LaAlO3 single crystal may not be suitable for scintillation application;by comparing the energy levels structures of Ce:LaAlO3 and Ce:Lu2.SiO4)O,the large energy difference(1.13 eV)between the two lowest 5d energy levels of Ce 3+ in LaAlO3 is a crucial factor that causes the luminescence quenching.

关键词： Ce:LaAlO3 Ce:Lu2.SiO4)O energy-level absorption luminescence

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CHEMICAL STRUCTURE DEPENDENCE OF THE INTERNAL energy CONTRIBUTION IN RUBBER ELASTICITY

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chinese Journal of Polymer Science 2001年第5期19卷 447-449页

作者： Juan Sun Xiao-zhen Yang Polymer physics Laboratory Center for Molecular sciences, {2. of Chemistry chinese academy of sciences Beijing 100080 china chinese Acad Sci Polymer Phys Lab Ctr Mol Sci Inst Chem Beijing 100080 Peoples R China

Conformational elasticity theory recently developed has been used to explore the internal energy contribution to the elastic force f(e)/f as a function of strain for poly(cis-1,4-isoprene) and poly(trans-1,4-isoprene). Calculated f(e)/f values are in good agreement with those obtained experimentally. Results show that behavior of f(e)/f is mainly contributed by chemical structure, or intramolecular interaction, supporting the experimental observations, and that the internal energy contribution is strain dependent.

关键词： conformational elasticity theory internal energy contribution poly(cis-1,4-isoprene) poly(trans-1,4-isoprene)

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Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china Earth sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3 & DENG Jun1 1 State Key Laboratory of Geological Processes and Mineral Resources,china University of Geosciences,Beijing100083,china 2.Laboratory of Nuclear Analysis Techniques,institute of high energy physics,chinese academy of sciences,Beijing 100039,china 3 Department of Geology,Peking University,Beijing 100871,china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―350℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―132.Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

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Dynamical Evolution of Gamma-Ray Burst Remnants with Evolving Radiative Efficiency

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 525-532页

作者： Jin-Bo Feng, Yong-Feng Huang, Zi-Gao Dai and Tan Lu1 Department of Astronomy, Nanjing University, Nanjing 2.00932.LCRHEA, institute for high-{2. physics, chinese academy of sciences, Beijing 100039 LCRHEA Institute for High-Energy Physics Chinese Academy of Sciences Beijing 100039

In previous works, a generic dynamical model has been suggested by Huang. et al., which is shown to be correct for both adiabatic and radiative blast-waves, in both ultra-relativistic and non-relativistic phases. In deriving their equations, Huang et al. have assumed that the radiative efficiency of the fireball is constant. They then applied their model directly to realistic cases where the radiative efficiency evolves with time. In this paper, we abandon the above assumption and re-derive a more accurate dynamical equation for gamma-ray burst remnants. Numerical results show that the model presented by Huang et al. is accurate enough in general cases.

关键词： gamma rays : bursts hydrodynamics radiation mechanisms : nonthermal

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A Study of Electromagnetic Transition of Δ(12.2.Resonance

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Communications in Theoretical physics 2004年第7期 87-89页

作者： DONG Yu-Bing LIU Jian institute of high {2. physics, the chinese academy of sciences, Beijing 100039, china

Point form relativistic dynamics of relativistic quantum mechanics is employed to estimate the photonand electroproduction amplitudes of Δ(12.2. *** are compared with the non-relativistic work,and thedifferences betw... 详细信息

关键词： relativistic quantum mechanism point form dynamics

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Monaural voiced speech segregation based on elaborate harmonic grouping strategies

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Science china(Information sciences) 2011年第12期54卷 2491-2500页

作者： LIU WenJu 1 , ZHANG XueLiang 1 , JIANG Wei 1 , LI Peng 2.& XU Bo 2.1 National Laboratory of Pattern Recognition, institute of Automation, chinese academy of sciences, Beijing 100190, {2. 2.Digital Media Content Technology Research Center, institute of Automation, chinese academy of sciences, Beijing 100190, {2. 1. National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100190 China2. Digital Media Content Technology Research Center Institute of Automation Chinese Academy of Sciences Beijing 100190 China

In this paper, an enhanced algorithm based on several elaborate harmonic grouping strategies for monaural voiced speech segregation is proposed. Main achievements of the proposed algorithm lie in three aspects. Firstly, the algorithm classifies the time-frequency (T-F) units into resolved and unresolved ones by carrier-to-envelope energy ratio, which leads to more accurate classification results than by cross-channel correlation. Secondly, resolved T-F units are grouped together according to minimum amplitude principle, which has been verified to exist in human perception, as well as the harmonic principle. Finally, "enhanced" envelope autocorrelation function is employed to detect amplitude modulation rates, which helps a lot in reducing half-frequency error in grouping of unresolved units. Systematic evaluation and comparison show that performance of separation is greatly improved by the proposed algorithm. Specifically, signal-to-noise ratio (SNR) is improved by 0.96 dB compared with that of previous method. Besides, our algorithm is also effective in improving the PESQ score and subjective perception score.

关键词： computational auditory scene analysis voiced speech separation harmonistic principle minimum amplitude principle elaborate harmonic grouping strategies

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On the sand surface stability in the southern part of Gurbantünggüt Desert

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中国科学：地球科学英文版 2005年第6期48卷 778-785页

作者： WANG Xueqin1,2. WANG Tao1, JIANG Jin2.& ZHAO Congju2.1. Laboratory of Blown Sand physics and Desert Environment, Cold and Arid Regions of Environmental and Engineering Research In-stitute, chinese academy of sciences, Lanzhou 730000, {2. 2. Xinjiang institute of Ecology and Geography, chinese academy of sciences, Urmqi 830011, {2. Correspondence should be addressed to Wang Xueqin 1. Laboratory of Blown Sand physics and Desert Environment Cold and Arid Regions of Environmental and Engineering Research In-stitute Chinese Academy of Sciences 730000 Lanzhou China 2. Xinjiang institute of Ecology and Geography Chinese Academy of Sciences 830011 Urümqi China

Longitudinal dunes are the most widespread dune types in the world sand seas but comprehensive study on the sand surface stability is scarce. The southern part of Gurbantnggt Desert is mainly covered by longitudinal dune in which fixed and semi-fixed dunes occupy over 80% of the total area. Systematic analysis on the climatic conditions, the soil moisture and vegetation distributions, and the sand surface activities showed that the fixed and semi-fixed dunes are in a comprehensive low-energy wind environment. Snow cover and frozen soil provide a good protection to the ground surface in winter. The temporal distribution of precipitation and corresponding variation of temperature create a favorable condition for the desert plants growth, especially for the ephemeral plants. The occurrence of effective winds for sand moving in April to June coincides with the stage of relatively wet sand surface and good vegetation cover, which effectively keep the sand surface stable at the interdune and the plinth of the dunes. Activity sand surface appears only at the crest and the upper part of the sand dunes.

关键词： Gurbantünggüt Desert, longitudinal dune, sand surface stability.

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Nonlinear analysis on the coupling process of electromagnetic vibrator and earth

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Science china Earth sciences 2005年第8期48卷 1175-1182页

作者： CHEN Zubin1,2. TENG Jiwen2. LIN Jun1, ZHANG Linhang1 & JIANG Zhongjin1 1. institute of Intelligent Instrument & Measurement Control Technology, Jilin University, Changchun 13002., china 2. institute of Geology & Geophysics, chinese academy of sciences, Beijing 10002., china 1. institute of Intelligent Instrument & Measurement Control Technology Jilin University 130026 Changchun China 2. institute of Geology & Geophysics Chinese Academy of Sciences 100029 Beijing China

The linear model based on the hydraulic pressure vibrator has been no longer adaptable to the electromagnetic vibrator. In order to realize the effective transmission of the limited energy from the vibrator to the ground, it is important to study the coupling model of the electromagnetic vibrator and the earth. In this paper, a nonlinear restore term was introduced to the coupling model because of the existence of a large amount of harmonics in the vibrator baseplate. The nonlinear vibration analysis was applied to the model by the multiscale method. In the course of energy transmission from the vibrator to the ground, ultraharmonic resonance was used to explain the generation of harmonics. An improved scheme was advanced to select the cross correlation reference signal in the vibrator seismic exploration. Good application results were obtained in field experiments.

关键词： vibrator, coupling model, electromagnetic, nonlinear vibration.

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Conceptual transition from molecular to atomic: unleashing a new era in hydrogen therapy for chronic disease

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National Science Review 2024年第04期11卷 17-18页

作者： Zhigang zou Eco-materials and Renewable energy Research Center (ERERC) Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State Microstructures and Department of PhysicsNanjing University

The dysregulated overexpression of reactive oxygen and nitrogen species (RONS)intricately links to the occurrence and development of diverse chronic diseases[1–3]. Hydrogen therapy stands out as a promising treatment methodology recognized for effectively mitigating RONS and maintaining intracellular redox equilibrium, thereby yielding therapeutic benefits [4,5].

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