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Chinese Science Bulletin 2003年第22期48卷 2500-2506页

作者： wan yusheng1,2. ZHANG Qiaoda1 & SONG Tianrui1 1. Institute of Geology, Chinese Academy of Geological Sciences,{2., china 2. beijing shrimp laboratory,{2., china correspondence should be addressed to wan yusheng (e-mail: wanyusheng@***) Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

The Mesoproterozoic Changcheng System is widely distributed in the North china Craton. Determining its time of deposition and sources is important to understand the Precambrian crustal evolution of the North china Craton. This paper suggests age distribution patterns for detrital zircons from clastic sediments of the Changcheng System in the Ming Tombs area, {2.. Samples of feldspar-bearing sandstone (CHc-2. and pure sandstone (CHc-9) were collected from the Changzhougou Formation, which constitutes the basal part of the Changcheng System. Detrital zircons show an age range from 2.35 to 2.60 Ga. However, sample CHc-9 in the upper Changzhougou Formation also contains some zircons with ages of 1.9-1.8 Ga and 2.3-2.1 Ga. The age patterns lead to the following conclusions: (1) Most of the detrital material came from a source area composed predominantly of ~2.5 Ga continental crust of the North china Craton; (2. 1.9-1.8 Ga reflects the age record of Palaeoproterozoic continent-continent collisional event in the North china Craton; and (3) the oldest age for deposition of the Changcheng System is 1.8 Ga.

关键词：锆石原岩中国北部地区地壳演变

Controlled assembly of copper phthalocyanine with 1-iodooctadecane

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Chinese Science Bulletin 2003年第15期48卷 1519-1524页

作者： LEI Shengbin, wanG Chen, wan Lijun & BAI Chunli Center of Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, {2. 100080, china correspondence should be addressed to Bai Chunli (e-mail: clbai@ ***) Center of Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The binary assembly behavior of 1-iodoocta- decane with substituted phthalocyanine (Pc) is studied using the scanning tunneling microscopy (STM). By altering the substituted alkyl groups attached to the phthalocyanine ring, either uniform assembly or phase separation behavior can be observed. It is suggested that the strength of intermolecular interaction between phthalocyanine molecules is the determining factor for the assembly structure.

关键词：铜酞菁碘代十八烷扫描隧道电子显微镜化学结构

Synthesis and ordered aggregation in water of a blue light-emitting PEO-PHP-PEO triblock oligomer

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Chinese Science Bulletin 2003年第15期48卷 1525-1530页

作者： HE Haifeng, CAO Hongqing, wan Xinhua, TU Yingfeng, CHEN Xiaofang & ZHOU Qifeng Department of Polymer Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, beijing 100871, {2. correspondence should be addressed to wan Xinhua (e-mail: xhwan@***) Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University

A novel blue light-emitting coil-rod-coil triblock oligomer, PEO-PHP-PEO, which consists of para-hexaphenyl (PHP) as the rigid rod and poly(ethylene oxide) (PEO, M w = 750) as the flexible coil, has been synthesized. It is the first soluble poly(para-phenylene) molecule containing no lateral substituent, which can dissolve not only in organic solvents such as chloroform and THF, but also in water. The critical micelle concentration (CMC) of PEO-PHP-PEO in water is 5.2.×10-4 mol·L-1 and the surface tension at CMC, 鉉MC, is 61.2. mN·m-1. The absorption peak of the molecularly dissolved PEO-PHP-PEO in water is centered at 32. nm and the fluorescence spectrum has a maximum at 432.nm and shows the vibronic fine structure typical of molecular dissolution. The photoluminescence spectrum of the aggregate solution is similar to that of the PHP polycrystal film, indicating that the ordered packing of PHP block has taken place due to a combination of hydrophobic interaction and p-p stacking. The oligomer self-assembles into cotton-like nanofibers with diameter of about 2. nm in 5.0×10-3 mol·L-1 aqueous solution.

关键词：合成工艺低聚物聚乙烯荧光光谱 PHP 对六苯基

Study of-amyloid adsorption and aggregation on graphite by STM and AFM

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Chinese Science Bulletin 2003年第5期48卷 437-440页

作者： wanG Zhigang, wan Lijun, ZHOU Chunqing, FANG Xiaohong, wanG Chen & BAI Chunli Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china correspondence should be addressed to Bai Chunli (e-mail: clbai@ ***)

The scanning tunneling microscopy (STM) and the atomic force microscopy (AFM) have been applied to the direct study of the adsorption and aggregation of -amyloid(1-42.(A42. on the hydrophobic graphite surface. It was found that A42.were preferentially adsorbed on graphite defects such as the edges. A42.peptides self-assembled into intermediate protofibrils, which in turn self-associated to form fibrils. Usually, two or more fibrils intertwined to form the helical structure. These results will provide an important clue to studying the aggregation proc-ess of -amyloid.

关键词： β-环糊精石墨吸附聚集扫描隧道显微镜原子力显微镜早老性痴呆药物载体

Zircon shrimp U-Pb dating for the Cangshuipu volcanic rocks and its implications for the lower boundary age of the Nanhua strata in South china

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Science Bulletin 2003年第16期48卷 1663-1669页

作者： wanG Jian1, LI Xianhua2. DUAN Taizhong3, LIU Dunyi4, SONG Biao4, LI Zhongxiong1 & GAO Yonghua5 1. Chengdu Institute of Geology and Mineral Resources, china Geologi-cal Survey, Chengdu 610082. china 2. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 3. Colorado School of Mines, Golden, CO 80401-1887, USA (Present address: Marathon Oil Company, Houston, TX 77056-2.2., USA) 4. Institute of Geology, Chinese Academy of Geological Sciences, Bei-jing 1.0037, china 5. Graduate School of the Chinese Academy of Geological Sciences, beijing 1.0037, china correspondence should be addressed to wang Jian (e-mail: jianwang@ ***) Chengdu Institute of Geology and Mineral Resources China Geological Survey Chengdu 610082 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Colorado School of Mines Golden CO 80401-1887 USA Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Graduate School of the Chinese Academy of Geological Sciences Beijing 100037 China

The continental volcanic rocks and volcaniclas-tic sedimentary conglomerates of the Cangshuipu Formation occur well in Yiyang of Hunan Province, consisting of a wedge-shaped succession of Neoproterozoic strata that over-lie with high-angle unconformity the flysch turbidites of the Lengjiaxi Group in the Upper Mesoproterozoic Eonothem. shrimp zircon U-Pb dating gives a weighted mean age of 814 12.Ma for the dacitic volcanic agglomerates from the lowest part of the volcanic rocks in the Cangshuipu Forma-tion. This age is younger than previously reported values of 92.—933 Ma for the volcanic rocks from the Cangshuipu Formation. Our new dating represents the lower boundary age of the Neoproterozoic System in the studied area. The younger age for the Cangshuipu volcanic rocks is supported by the following observations: （1） Lower Neoproterozoic strata （814—1000 Ma） are missing in the studied area; （2. the Nanhua rift system was initiated at about 82. Ma; and （3） an age of82. Ma may be taken as the lower boundary tim-ing of the Nanhua System （even Neoproterozoic） in South china.

关键词： Zicon U-Pb dating Neoproterozoic volcanics rift basin Nanhua System.

Slow Light Effect and Multimode Lasing in a Photonic Crystal Waveguide Microlaser

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Chinese Physics Letters 2010年第2期27卷 123-126页

作者：邢名欣郑婉华周文君陈微刘安金王海玲 Nano-optoelectronics Lab Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 State Key laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083

The slow light effect in a photonic crystal waveguide is investigated theoretically and experimentally. Theoretical calculation indicates that there is a slow light region for the even mode, from which the resonance and lasing in a microcavity would benefit. A photonic crystal waveguide microlaser is fabricated, which is related to the group velocity of c/12..6.

关键词： Chinese climate network complex systems small world community