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Direct CP violation in hadronic B decays

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science china({2.,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3.1. Department of physics, Lishui University, Lishui 3.0}000,{3. 2. Department of physics, shanghai Jiaotong University, shanghai 2.003., {3. 3. institute of High Energy physics, Beijing 100049,{3. Department of physics Lishui University Lishui 323000 China Department of physics Shanghai Jiaotong University Shanghai 200030 China institute of High Energy physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

CO observations of massive star forming regions at different evolutionary phases

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science china({2.,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2. XU Ye1,3. SHEN Zhiqiang1,3.& LI Jingjing1,2.1. shanghai Astronomical Observatory, {3. Academy of {2.s, shanghai 2.003., china 2. Graduate School of the {3. Academy of {2.s, Beijing 10003., china 3. Joint institute for Galaxy and Cosmology, shanghai Astronomical Observatory and the University of {2. and Technology of china, shanghai 2.003., china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate School of the chinese Academy of sciences Beijing 100034 China Joint institute for Galaxy Cosmology Shanghai Astronomical Observatory the University of science Technology of china Shanghai 200030 China

The 12.O (J=1-0), 13.O (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain Observatory. Of the observed 9 sources, 13.O cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2. masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 2.566+582. in the observing field of S152.S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2. maser simulta- neously.

关键词： star formation cloud core outflow H2. maser

β-delayed proton decays near the proton drip line

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science china({2.,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern {3., {2. Academy of sciences, Lanzhou 73.000, china 2. Nuclear {3. Department, china institute of Atomic Energy, Beijing 102.13. china 3. Department of {13. {3., Peking University, Beijing 100871, china 4. {12. institute for Nuclear Research, {12. 2.1800, china 1. institute of Modern physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of technical physics Peking University 100871 Beijing China 4. shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142.o and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Ultrafast excitation relaxation in light-harvesting complex LH2.from *** 601

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science china Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2. LIU Yuan3. LIU Weimin2. GUO Junhua1, XU Chunhe3.& QIAN Shixiong2.1. School of {3. and Information Optoelectronics, Henan University, Kaifeng 475001, china 2. {3. Department, Fudan University, shanghai 2.043., china 3. shanghai institute of Plant Physiology, chinese Academy of {13.s, shanghai 2.003.0} china 1. School of physics and Information Optoelectronics Henan University 475001 Kaifeng China 2. physics Department Fudan University 200433 Shanghai China 3. shanghai institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2.from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783.nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.3. ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.

Anticoagulation property and security of artificial heart valve material

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science china(Technological sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,2., 3. ZHANG Feng2. LI Changrong2. YU Liujiang2. ZHENG Zhihong2. WANG Xi2. JIANG Zhenbin4, CHEN Anqing4 & XU Jingfang3.1. Department of physics, East china Normal University, {2. 2.0062. china 2. Ion Beam Lab, {2. institute of Mini-system and information, chinese Academy of sciences,{2. 2.0050, china 3. Department of Electronics, School of Information science and Technology, East china Normal Univer- sity, {2. 2.0062. china 4. {2. Cardiovascular institute, Zhongshan Hospital, {2. 2.003.0} china 1. Department of physics East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. Department of Electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. shanghai Cardiovascular institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2.million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

Transverse patterns and spatiotemporal instability of a photorefractive oscillator

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chinese science Bulletin 1997年第9期42卷 724-729页

作者： ZHUANG Jun and TAN Weihan1. shanghai institute of Optics and Fine Mechanics, {2. Academy of {3.s, shanghai 2.1800, china 2. shanghai University, shanghai 2.1800, china shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China shanghai University Shanghai China

IN time realm,instability and chaos phenomena of a nonlinear optical system have been dis-cussed *** recent years,as much interest was attracted to the transverse ef-fects in nonlinear optics,the study was developed t... 详细信息

关键词： photorefractive oscillator spatiotemporal instability transverse patterns.

Optimum segmentation of simple objects in high-resolution remote sensing imagery in coastal areas

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science china Earth sciences 2006年第11期49卷 1195-1203页

作者： CHEN Jianyu1,2. PAN Delu1 & MAO Zhihua1 1. State Key Laboratory of Satellite Ocean Environment Dynamics, Second institute of Oceanography, State Oceanic Admini- stration, Hangzhou 3.0012. {3. {2., chinese Academy of science, shanghai 2.0083. china 1. State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China 2. shanghai institute of technical physics Chinese Academy of Science Shanghai 200083 China

The optimum segmentation of ground objects in a landscape is essential for interpretation of high-resolution remotely sensed imagery and detection of objects; and it is also a technical foundation to efficiently use spatial information in remote sensing imagery. Landscapes are complex system composed of a large number of heterogeneous components. There are many explicit homogeneous image objects that have similar spectral character and yet differ from surrounding objects in high-resolution remote sensing imagery. Thereby, a new concept of Distinctive Feature of fractal is put forward and used in deriving Distinctive Feature curve of fractal evolution in multiscale segmentation. Through distinguishing the extremum condition of Distinctive Feature curve and the inclusion relationship of fractals in multiscale representation the Scalar Order is built. This can help to determinate the optimum scale in image segmentation for simple-objects, and the potential meaningful image-object fitting the intrinsic scale of the dominant landscape object can be obtained. Based on the application in high-resolution remote sensing imagery in coastal areas, a satisfactory result was acquired.

关键词： optimum scale, multiscale segmentation, image interpretation, remote sensing, coastal area.

Predominant expression of β-chain variable region genes of T-cell receptor in TILs from human renal cell carcinoma

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chinese science Bulletin 1997年第8期42卷 693-697页

作者： LI Xueyi, WANG Ying, ZHENG Zhongcheng, ZHANG Dongqing, FUSaili, LING Jianyu and ZHOU Guangyan (CHOU Kuangyen)1. shanghai institute of Immunology, shanghai Second Medical University, shanghai 2.002., china 2. shanghai institute of Biochemistry, chinese Academy of sciences, shanghai 2.003., china 3. shanghai Ruijin Hospital, shanghai 2.002., china shanghai institute of Immunology Shanghai Second Medical University Shanghai China shanghai institute of Biochemistry Chinese Academy of Sciences Shanghai China shanghai Ruijin Hospital Shanghai China

THE repertoire of T-cell antigen receptor(TcR)can be effectively analysed by an approachwith quantitative polymerase chain reaction(qPCR),which allows to characterize the ex-panding T-cell clones by the patterns of re... 详细信息

关键词： renal cell carcinoma tumor-infiltrating lymphocyte T-cell receptor Vβ gene quantitative polymerase chain reaction.

Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2. GAO Chenxi1,2.3.& HAN Bin1,3.41. National Center for Gene Research, shanghai {3.s for Biological {2.s, chinese Academy of {2.s, shanghai 2.02.3. china 2. Graduate School of the chinese Academy of {2.s, Beijing 10003., china 3. {3. of Plant Physiology and Ecology, shanghai {3.s for Biological {2.s, chinese Academy of {2.s, shanghai 2.003.0} china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China Graduate School of the chinese Academy of sciences Beijing 100039 China institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3.-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12.69 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953.genes. The al- ternative poly(A) sites were revealed in approxi- mately 2.% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3. fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3. fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程