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Formation of complexes of Rubisco-Rubisco activase from La^3+, Ce^3+ treatment spinach

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science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2.& ZHAO Guiwen3 1. College of Life sciences, Suzhou Universty, Suzhou 2.5006, china {2., institute of high energy Physics, the chinese academy of science, beijing 100039, china 3. Chemical Department, University of science and Technology of china, Hefei 2.002., china 1. College of Life sciences Suzhou Universty 215006 Suzhou China 2. synchrotron radiation laboratory Institute of High Energy Physics The Chinese Academy of Science 100039 Beijing China 3. Chemical Department University of Science and Technology of China 230026 Hefei China

The complex of Rubisco and Rubisco activase from LaCl3-, CeCl3- treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3-, CeCl3- treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3-, CeCl3-treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 36—39 –SH per mol enzyme, 14—2. –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3-, CeCl3 -treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3-, CeCl3- treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3+, Ce3+, spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

Studies on BEPC upgrade from pretzel to double-ring

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science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2084-2089页

作者： ZHANG Chuang institute of high {2. Physics,chinese academy of sciences,beijing 100049,china 1. institute of high {2. Physics Chinese Academy of Sciences Beijing 100049 China

Physics opportunity in the charm and τ energy region calls for higher luminosity of the {2. Electron-Positron Collider (BEPC).The BEPC has experienced continuous improvement since its completion in ***,as a major upgrading project of the BEPC,aims at enhancing its luminosity of factor 30–100,following the principle of "one machine,two purposes" as adopted in BEPC,so that both high energy physics and synchrotron radiation experiments can be carried out with *** the BEPC to BEPCII,the double-ring scheme with multi-bunch e +-e-collision in the large crossing angle was studied in comparison with the single-ring pretzel *** the dedicated synchrotron radiation operation,artful "bridges" are designed to connect two halves of the outer ring in both the southern and the northern crossing *** paper reviews the studies on the BEPC upgrade from pretzel to double-ring structure of BEPCII.

关键词： collider storage ring high energy physics synchrotron radiation

INVESTIGATION ON THE VALENCE STATE OF Ce ATOMIN BULK AND NANOCRYSTAL CeO_2.BY X-RAY ABSORPTION ANDPHOTOEMISSION

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 511-516页

作者： K. Ibrahim, Z.Y. Wu, J. Zhang, M.I. Abbas, F.Q. Liu and H.J. Qian (beijing synchrotron {2. laboratory, institute of high energy Physics, the chinese academy of sciences, P.O. Box 918, beijing 100039, china) beijing synchrotron Radiat. Lab. Inst. of High Energy Phys. Chinese Acad. of Sci. P.O. Box 918 Beijing 100039 China

Valence band photoemission spectra (PES) for both bulk and nanocrystal CeO2.have been measured on and off resonance of Ce 4d-4f absorption edge. The PES show that the bulk and nanocrystal CeO2.of diameter ranging from 8nm to 50nm exhibit a peak near Fermi edge with binding energy of about 1.8eV. The 1.8eV peak shows a strong dependence on excitation energy, although it looks like the contribution of Ce3+ ion following the data reported in literatures. However, according to the results of resonance photoemission and X-ray absorption spectra at 1s edge, this electronic structure may be associated to the intermediate state charge transfer effects.

关键词： rare earth oxide photoemission electronic structure photoabsorption

Structural stability of infinite-layer CaCuO_2.under high pressure

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chinese science Bulletin 2003年第12期48卷 1201-1203页

作者： QIN Xiaomei1,2. HONG Ming1,2. ZHANG Gongmu1,2. MAI Wenjie1,2. LI Fengying1,2. YU Richeng1,2. LIU Jing2.3 & JIN Changqing1,2.1. institute of Physics, chinese {2. of sciences, beijing 100080, china 2. beijing high Pressure Research Center, beijing 100080, china 3. institute of high {12. Physics, chinese {2. of sciences, beijing 100039, china Correspondence should be addressed to Jin Changqing (e-mail: cqjin@ ***) institute of Physics Chinese Academy of Sciences Beijing 100080 China beijing high Pressure Research Center Beijing 100080 China institute of high {2. Physics Chinese Academy of Sciences Beijing 100039 China

In situ high-pressure energy dispersive X-ray diffraction measurements on polycrystalline powder Ca-CuO2.with an infinite layer structure (IL CaCuO2. have been performed by using diamond anvil cell (DAC) instrument with {2. radiation. The results suggest that the crystal structure of IL CaCuO2.is stable under pressure up to 30 GPa at room temperature. According to Birch-Murn- aghan equation of state, assuming pressure derivative 4,=0Bthe bulk modulus B0=181 ?9 GPa is obtained.

关键词： infinite-layer CaCuO2 synchrotron radiation high pressure energy dispersive X-ray diffraction.

Exotic structure of the third excited state in^(2.)Na

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chinese science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2.3, LIANG Yujie1,2.3, DENG Fuguo1,2.3, LIU Zuhua1,4 & ZHOU Hongyu1,2.3 1. Key laboratory of Beam Technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875, china 2. institute of Low energy Nuclear Physics, and Department of Material science and Engineering, beijing Normal University, beijing 100875, china 3. beijing radiation Center, beijing 100875, china 4. china institute of Atomic energy, beijing 102.13, china Key laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China institute of Low energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing radiation Center Beijing 100875 China china institute of Atomic {2. Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficie... 详细信息

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (2.1/2. of the third excited state in 2.Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73% and 2.1/2.5.2. fm respectively. The P value and the contribution of the asymptotic part to the 2.1/2.are compared with those of several other low energy states in 2.Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 2.Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 2.Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

RESONANT PHOTOEMISSION OF BULK CeO_(2. AND NANO-CeO_(2. FILMS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 539-543页

作者： M.I. Abbas, K. Ibrahim, Z.Y. Wu, J. Zhang, F.Q. Liu and H.J. Qian (beijing synchrotron {2. laboratory, institute of high energy Physics, the chinese academy of sciences, P.O. Box 918, beijing 100039, china) beijing synchrotron Radiat. Lab. Inst. of High Energy Phys. Chinese Acad. of Sci. P.O. Box 918 Beijing 100039 China

Photoemission behaviors of nano-CeO2.films with particle sizes ranging from 8 nm to 50 nm and bulk CeO2.in Ce 4 d-4 f absorption region have been investigated. Resonant enhancements of Ce 4 f valance band and Ce 5 p bands for nano film and bulk material have been observed. The variation of electron density of states in valance bands of nano and bulk structures of CeO2.is discussed in terms of Ce 4 d-4 f resonance.

关键词： Nanostructured materials Optical films Oxides Photoemission Resonance

Structure Relaxation of Mg_(65)Cu_(2.)Gd_(10) Metallic Glass and Its Effect on Strength

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Journal of Wuhan University of Technology(Materials science) 2009年第2期24卷 210-213页

作者：李国强 School of Materials science & Engineering Beijing University of Aeronautics and Astronautics china Perfect Machinery Industry Corp. Ltd

To identify the re-arrangement of constituent atoms of an amorphous Mg65Cu2.Gd10 alloy happened with annealing, structure relaxation of the alloy was investigated as a function of an- nealing time at 373 K through extended X-ray absorption fine structure （EXAFS） analysis procedures. To understand the effect of structure relaxation on strength, compression tests were conducted for both the as-cast and the annealed Mg65Cu2.Gd10 samples. It is found that short range order around Cu and Gd atoms exhibits different variation trends with increasing annealing time at 373 K, though the structure of the alloy still remains to be amorphous. Based on the fact that the strength of the alloy first exhibits a reduction and then a recovery with annealing time, it is suggested that the enhancement of short range order around Cu should be responsible for the strength reduction, while the enhancement of short range order around Gd should be responsible for the strength recovery.

关键词： Mg-based metallic glass structure relaxation strength annealing

In situ study on dendrite growth of metallic alloy by a synchrotron radiation imaging technology

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science china(Technological sciences) 2010年第5期53卷 1278-1284页

作者： WANG TongMin1,XU JingJing1,LI Jun1,HUANG WanXia2.LIU ShengChu1 & LI TingJu1 1 School of Materials science and Engineering,Dalian University of Technology,Dalian 11602.,china 2.{2. of high energy Physics,chinese academy of sciences,beijing 100039,china 1. School of Materials science and Engineering Dalian University of Technology Dalian 116024 China2. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China

This study was trying to observe the real-time dendrite growth of Sn-Bi and Sn-Pb binary alloys by a synchrotron radiation imaging *** imaging system includes an intense and {2. brightness synchrotron radiation source,a {2.-resolution and fast-readout charge coupled device camera,an alloy sample and a Bridgman solidification *** imaging experiments were done at beijing synchrotron radiation Facility with an updated synchrotron radiation imaging technique,diffraction-enhanced imaging,which was firstly used to study the dendrite growth of metallic alloy.A series of growth behavior and morphology evolution of dendrite have been in situ observed,such as columnar-to-equiaxed transition,dendrite competition,dendrite fragmentation and floating,etc.,which can offer the direct proofs to verify or improve the solidification theories of metallic *** research opens a novel window for the study of alloy solidification and enables the unambiguous understanding of solidification processes in optically opaque,metallic alloys.

关键词： dendritic growth synchrotron radiation solidification diffraction-enhanced imaging metal and alloys

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4,5 1 Key laboratory of Beam Technology & Materials Modification of the Ministry of Education, institute of Low {2. Nuclear Physics, beijing Normal University, beijing 100875, china 2.beijing radiation Center, beijing 100875, china 3 laboratory of Optical Physics, institute of Physics, {12. academy of sciences, beijing 100080, china 4 Key laboratory of Advanced Materials of the Ministry of Education, Department of Materials science and Engineering, Tsinghua University, beijing 100084, china 5 beijing National Center for Electron Microscopy, Tsinghua University, beijing 100084, china 1. Key laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China 2. beijing radiation Center Beijing 100875 China 3. laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 4. Key laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing 100084 China 5. beijing National Center for Electron Microscopy Tsinghua University Beijing 100084 China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport