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Genesis of excess argon in phengite and significance of ^(40)Ar-^(39)Ar age spectra for omphacite:A case study on UHP eclogite of South Dabie Terrain,china

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Chinese science Bulletin 2000年第15期45卷 1345-1351页

作者： WANG Songshan, GE Ningjie, SANG Haiqing & QIU ji1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 10002., china 2. {2. of Earth and Space science, university of science and Technology of china, Hefei 2.002., china correspondence should be addressed to Wang Songshan Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China department of Earth and Space science University of Science and Technology of China Hefei China

The Ar-Ar dating of phengite and omphacite in ultrahigh-pressure (UHP) eclogite of Bixiling and Hengchong in the South Dabie Terrain shows that the content range of excess argon is as high as (0.4-1.3)×10 8 mol· g 1. The genesis of the excess argon is discussed. The Ar-Ar age spectra of omphacite could not support the opinion that the UHP metamorphism occurred in Caledon epoch and pre-Caledon epoch.

关键词： South Dabie Terrain ultrahigh-pressure metamorphics phengite omphacite excess argon.

Brassinosteroid signal trans-duction: An emerging picture

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Chinese science Bulletin 2003年第18期48卷 1906-1912页

作者： WANG Qiaomei1 & MA Ligeng2.1. department of Horticultural science, Zhejiang {2., Hangzhou 31002., china 2. department of Biology, Hebei Normal {2., Shijiazhuang 050016, china correspondence should be addressed to Ma Ligeng (e-mail: ligeng.ma @yale.edu) department of Horticultural science Zhejiang University department of Biology Hehei Normal University Shijiazhuang

Steroid hormones play essential roles in animal growth and development. Steroid signaling in animal system is focused on the direct gene regulation response mediated by its nuclear receptors. Recently, steroid hormones are also found in plants. Identification of BRI1 — a critical compo-nent of the plasma-membrane steroid receptor complex, and the related signal transduction pathway mediated by the membrane receptor have revealed an elementary picture of BR signaling from the cell surface perception to the activa-tion of BR-responsive nuclear genes.

关键词： plants Brassinosteroids signal transduction BRI1 cross talk.

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. Institute of Laser Physics and Chemistry, Sichuan university, Chengdu 610064, china 2. {2. of Physics, Luoyang Normal College, Luoyang 47102., china 3. State Key Laboratory of Laser Technology, Huazhong university of science and Technology, Wuhan 430074, china correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 Institute of Laser Physics and Chemistry Sichuan University Chengdu China State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan China department of Physics Luoyang Normal College Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Synthesis of vertically aligned carbon nanotube arrays on silicon substrates

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science china(Technological sciences) 2004年第5期47卷 616-624页

作者： ZHENG Ruiting1, CHENG Guoan1, PENG Yibin1, 2. ZHAO Yong1, 3, LIU Huaping1 & LIANG Changlin1 1. Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education, department of Materials science and Engineering, Beijing Normal {2., Beijing 100875, china 2. School of science, Civil Aviation {2. of china, Tianjin 300300, china 3. department of Physics, nanchang {2., nanchang 330047, china correspondence should be addressed to Zheng Ruiting Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education Department of Materials Science and Engineering Beijing Normal University

The growth of well-aligned carbon nanotube (CNT) arrays using a heat chemical vapor deposition system on silicon substrates is reported. The growth properties of CNT arrays are studied as a function of synthesis conditions. It is found that 750°C and 10 nm Fe film are suitable conditions for the growth of well-aligned CNT arrays. CNT arrays with a uniform diameter, thick tube wall and firm cohesion to the Si substrate can be grown for C2.2.concentration of 2.%. Based on the experiment, the processes of improving the alignment of CNT arrays and cohesion between CNT arrays and Si substrates are discussed.

关键词： carbon nanotubes, vertically aligned, silicon substrate, chemical vapor deposition.

Adsorption behavior of hexadecyltrimethylammonium bromide (CTAB) to mica substrates as observed by atomic force microscopy

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science china Chemistry 2005年第2期48卷 101-106页

作者： ZHAO Feng1,2. DU Yukou1, YANG Ping1, LI Xingchang2.& TANG ji’an2.1. Chemistry and Chemical Engineering department, Suzhou university, Suzhou 2.5006, {2. 2. Key Laboratory of Colloid and Interface science, Institute of Chemistry, Chinese Academy of sciences, Beijing 100080, {2. correspondence should be addressed to Tang ji’an (email: jatang@***) Chemistry and Chemical Engineering department Suzhou University Suzhou 215006 China

Atomic force microscopy is employed to study the adsorption behavior of CTAB to mica surfaces. Results show that conformational transitions from globular micelles→cylindrical micelles→flat films are observed in the process of the adsorption of CTAB to mica at twice the bulk critical concentration. However, in 0.5 cmc CTAB solution, the adsorbed CTAB molecules to mica form the layered film structures, and apparent conformational transitions do not appear. Meanwhile, the phenomena of the adsorption of CTAB to mica and the dissociation of mica sur- faces are periodically observed.

关键词： atomic force microscopy (AFM), micelle, behavior of adsorption, the dissociation of mica surfaces.

Novel ^(99m)Tc labeled σ r eceptor ligand as a potential tumorimaging agent

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science china Chemistry 2006年第2期49卷 169-176页

作者： FAN Caiyun1, jiA Hongmei1, Deuther-Conrad Winnie2. Brust Peter2. Steinbach J?rg2.& LIU Boli1 1. Key Laboratory of Radiopharmaceuticals (Beijing Normal university), Ministry of Education, department of Chemistry, Beijing Normal university, Beijing 100875, china 2. Institute of Interdisciplinary Isotope Research, Permoserstr. 15, 04318 Leipzig, Germany correspondence should be addressed to Liu Boli Key Laboratory of Radiopharmaceuticals (Beijing Normal university) Ministry of Education Department of Chemistry Beijing Normal University Beijing China Institute of Interdisciplinary Isotope Research Leipzig Germany

A novel ^(99m)Tc labeled complex,[N-[2.((2.oxo-2.(4-(3-phenylpropyl)piperazin-1-yl)ethyl)(2.mercaptoethyl)amino)acetyl]-2.aminoethanethiolato]Technetium(Ⅴ) oxide (PPPE-MAMA''-^(99m)TcO)([^(99m)Tc]-2. has been designed and prepared based on the integrated approach. The correspondingrhenium complex (PPPE-MAMA''-ReO)(Re-2. has been prepared and characterized. In vitro competitionbinding assays show moderate affinity of Re-2.towards σ_1 and σ_2.receptors with K_i values of8.67 ± 0.07 and 5.71 ± 1.88 μmol, respectively. Planar images obtained at 0.5 h, 4 h, 2. h afteri.v. injection indicate the accumulation of [^(99m)Tc]-2.in MCF-7 human breast tumor bearing mice at2. h. Furthermore, the accumulation of [^(99m)Tc]-2.has been inhibited at 2. h after co-injectionof [^(99m)Tc]-2.plus haloperidol (1 mg/kg). Biodistribution studies of [^(99m)Tc]-2.display an invivo tumor uptake of 0.14% ± 0.01% ID/g at 2. h post i.v. injection with a tumor/muscle ratio of6.02.± 0.87. The above results suggest that [^(99m)Tc]-2. derived from a previously published leadcompound, retains certain tumor uptake and affinity for σ receptors. [^(99m)Tc]-2.may be used as abasis for further structural modifications to develop tumor imaging agents with high affinity for σreceptors.

关键词： tumor σ receptor SPECT ^(99m)Tc

Synthesis, crystal structure and properties of binuclear manganese complex [(bipy)_2.n_2./J-O)(/i-Ac)_2.H_2.)_2.(ClO_4)_2

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Chinese science Bulletin 2000年第12期45卷 1079-1082页

作者： LI Jun, YANG Shuming, ZHANG Fengxing, TANG Zongxun, SHI Qizhen & ZHOU Zhongyuan1. department of Chemistry, Northwest university, Xi’an 710069, {2. 2. Chengdu Institute of Organic Chemistry, Chinese Academy of sciences, Chengdu 610041, {2. correspondence should be addressed to Li Jun department of Chemistry Northwest University Xi’an China Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu China

Binuclear manganese complex [(bipy)2.n2.μ-O)(μ-Ac)2.H2.)2.(CIO4)2.was synthesized by the reaction of MnAc3 · 2.2. with 2.2.-bipyridine in the HAc-NaAc buffer (pH = 4.0). X-ray diffraction result for the single crystal shows that the crystal is monoclinic, space group C2.C, with a = 3.4082.7), 6 = 0.8644(2., c= 2.174 9(4) nm,β= 105.2., V =6.186(2. nm3, Z= 8. There are two very strong peaks of UV-Vis spectrum in the range of 400-600 nm, which are similar to those of Mn catalase and Mn ribonuleotide reductase extracted from organisms. Cyclic voltammogram shows that the complex in CH3CN undergoes quasi-reversible one-electron reduction and oxidation at E1/2.1.15V.

关键词： binuclear manganese complex crystal structure synthesis properties.

Doubly contracted CI method and applications

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science china Chemistry 2004年第4期47卷 276-282页

作者： WANG Yubin1, HAN Huixian1, ZHAI Gaohong2.,SUO Bin1 & WEN Zheny1,2.1. Institute of Modern Physics, Northwest university, Xian 710069, china 2. Laboratory of Physico-Inorganic Chemistry, {2. of Chemistry, Northwest university, Xian 710069,china correspondence should be addressed to Wen Zhenyi Institute of Modern Physics Northwest University Xian China Laboratory of Physico-Inorganic Chemistry Department of Chemistry Northwest University Xi’an China

Based on the hole-particle correspondence an approximate so-called doubly contracted CI scheme is proposed. Examples calculated based on the doubly contracted CI (DCCI) scheme show that the number of configurations after contraction is reduced by three orders of magnitude, and the computation time is reduced by an order of magnitude. The examples also show that compared with experiments the DCCI and uncontracted CI have similar and reasonable accuracy to some spectroscopic parameters.

关键词： doubly contracted CI hole-particle symmetry approximate MRCI

Genesis of continental seismogenic zone and a new fault zone model

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Chinese science Bulletin 2000年第20期45卷 1886-1892页

作者： LIU Junlai & M. Shimada1. department of Earth sciences, Changchun {2. of science and Technology, Changchun 13002., china 2. RCEP, Disaster Prevention Research Institute, Kyoto {2., Uji, Kyoto, 611-0011, Japan correspondence should be addressed to Liu Junlai i department of Earth sciences Changchun University of Science and Technology Changchun China RCEP Disaster Prevention Research Institute Kyoto University Uji Kyoto Japan

Experiments were conducted repeatedly on Mannari granite under different temperature and confining pressure conditions. Systematic micro- and submicro-structural and mechanical analyses of granite samples deformed under 1.5 GPa (confining pressure), at 2. ℃-650 ℃ temperatures and at 2.10-6s-1 strain rate show the brittle-ductile deformation microstructures and microstructural associations similar to those observed in naturally deformed crustal rocks and minerals. Brittle fracturing and crystalline plasticity co-exist and react with each other in the brittle-ductile transition domain of the continental lithosphere. The interaction between the different mechanisms in the transitional domain results in the variation of anomalous strength values, which may best explain the genesis of the continental seismogenic zone. A new fault zone model is proposed on the basis of detailed micromechanical and microstructural analyses.

关键词： granite experimental rock deformation continental seismogenic zone fault zone model.