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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 China beijing shrimp {2. Beijing 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 2.3. 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

Wettability of CuNi-Ti Alloys on Si_3._4 and Interfacial Reaction Products

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Journal of Materials Science & Technology 1996年第3期12卷 219-222页

作者： Chuangeng wan Huaping XIONG and Zhenfeng ZHOU (Dept. of Materials Science and Engineering, Jilin University of Technology, Changchun 13.02., china)(To whom {2. should be addressed) Dept. of Materials Science and Engineering Jilin University of Technology Changchun 130025 China

Based on the alloy Cu55Ni45 (at pct), holding the proportion of Cu to Ni in constant and in the temperature range of 12.3.1573.K, the wetting angles of CuNi-0~56 at pct Ti alloys on Si3.4 have been measured by the sessile drop method. With the increase of Ti content, the wetting angles decreased. The equilibrium wetting angle was 5° when Ti content ≥3.0}at *** the case of same Ti content, the activity of Ti in CuNiTi alloy was weaker than that in CuTi alloy The cross-section of the CuNiTi-Si3.4 interface and the elements distribution were examined by scanning electron microscope with X-ray wave-dispersion spectrometer, and the reaction products formed at the interface were determined by X-ray diffiaction analysis method.

关键词： Si Ni Wettability of CuNi-Ti Alloys on Si3.4 and Interfacial Reaction Products Ti

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, {3. 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. {3. should be addressed to wan Xinhua (e-mail: xhwan@***) Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

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 3.0} nm and the fluorescence spectrum has a maximum at 43.0}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

Meteor radar observation of circulation near mesopause over Wuhan

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Chinese Science Bulletin 2003年第15期48卷 1634-1638页

作者： XIONG Jiangang, wan Weixin, NING Baiqi & LIU Libo Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 43.071, china {2. {3. be addressed to Xiong Jiangang (e-mail: xjg@***) Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China

The Wuhan meteor radar is the first all-sky meteor radar in china. The circulation near the mesopause from February to September 2.02.is studied based on the data obtained by the Wuhan meteor radar. The zonal wind is usually eastward in winter from 80 to 100 km. The mean zonal wind become westward from March to early of May, when the winter circulation reverses to the summer circulation. But at the meteor heights, the zonal circulation usually becomes eastward after the middle of May. The meridional circulation is always equatorward. The peaks of the meridional wind move downward with the height, and the peak value reaches its maximum of 2. ms-1 in July. Having made a comparison between monthly mean wind and HWM93.model wind, the value of southward wind, the maximal value of eastward wind as well as the reversal height of zonal wind are found to be quite different from each other.

关键词：武汉市气象雷达带状气流数据采集中间层顶

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 100037, china 5. Graduate School of the Chinese Academy of Geological Sciences, beijing 100037, china {13. should be addressed to wang Jian (e-mail: jianwang@ ***) Chengdu Institute of Geology and Mineral Resources China Geological Survey Chengdu China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Colorado School of Mines Golden USA Institute of Geology Chinese Academy of Geological Sciences Beijing China Graduate School of the Chinese Academy of Geological Sciences Beijing 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.—93. 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.

METHANE OXIDATIVE COUPLING: SYNERGISTIC PROMOTION OF BINARY METAL FLUORIDES TO THORIA BASED CATALYST ThO2.LaF3.BaF2

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Journal of Energy Chemistry 1996年第1期 31-44页

作者： ZHOU Xiao-Ping CHAO Zi-Sheng wan Hui-Lin TSAI Khi-Rui (Department of Chemistry, Xiamen University Xiamen, Fujian 3.1005 To whom correspondence {2. be {3.)

Methane oxidative coupling was investigated on ThO2.LaF3.ThO2.BaF2.and ThO2.LaF3.BaF2.catalysts. A synergistic promoting effect of binary metal fluorides BaF2.and LaF3.to metal oxide ThO2.was found over ThO2.LaF3.BaF2.catalyst. The analysis of phase composition shows that there are abundant. lattice defect in ThO2.LaF3.BaF2.catalyst. XPS and Raman charactenzation indicate that there exist O2.-, O2.and the intermediate oxygen species, and a large amount of quasi-free electrons over ThO2./LaF3.BaF2.catalyst.

关键词： methane oxidative coupling binary metal fluorides synergistic promotion. thoria based catalyst oxygen species

THE ADSORPTION OF OXYGEN OVER ThO2.BaF2.CATALYST

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Journal of Energy Chemistry 1996年第1期 22-30页

作者： ZHOU Xiao-Ping CHAO Zi-Sheng wan Hui-Lin TSAI Khi-Rui(Department of Chemistry, Xiamen University Xiamen, Fujian 3.1005 To whom correspondence {2. be {3.)

The adsorption of O2.over ThO2.BaF2.catalyst was studied at room temperature. Raman experiments reveal that there is much stronger adsorption of O2.on ThO2.BaF2.than on ThO2.XRD results suggest that ionic exchange exists between BaF2.and ThO2.phases forming the O-species and quasi-free electrons in ThO2.BaF2. The XPS, Raman and EPR results indicate that O2.-, O2. and intermediate oxygen species O2.- and O2.- (1更多还原AbstractFilter('ChDivSummary', 'ChDivSummaryMore', 'ChDivSummaryReset');

关键词： oxygen species metal fluoride ThO2.BaF2

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, {3. 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

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