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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

shrimp zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha Group in Tibet

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Science china Earth Sciences 2005年第9期48卷 1377-1386页

作者： HU Daogong1, WU Zhenhan1, JIANG wan1, SHI Yuruo2. YE Peisheng1 & LIU Qisheng1 1. Institute of Geomechanics, Chinese Academy of Geological Sciences, beijing 100081, {2. 2. Institute of Geology, Chinese Academy of Geological Sciences, beijing shrimp Centre, beijing 10003., {2. 1. Institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 2. Institute of Geology Chinese Academy of Geological Sciences Beijing SHRIMP Centre 100037 Beijing China

The Nyainqêntanglha Group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha Group, 10 km west of Nam Co in northern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (shrimp). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha Group is constrained by U-Pb age of 748±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha Group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the northern margin of the India shield. The inherited zircons from the tholetiite and granite give older 2.7Pb/2.6Pb ages from 947 to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time.

关键词： Nyainqêntanglha Group, shrimp dating, Nd isotope, Neoproterozoic, Tibet.

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

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SAR原始数据压缩的快速矢量量化器

系统工程与电子技术 2004年第10期26卷 1534-1536页

作者：赵宇鹏万锋雷宏中国科学院电子学研究所

回顾了矢量量化的各种快速算法,指出其在应用到SAR原始数据压缩中的局限性。为了将矢量量化应用到SAR原始数据实时压缩,提出一种基于查表的矢量量化器的设计方案,其中整合了其他的矢量量化算法。最后用各种快速算法以及BAQ算法进行了对... 详细信息

回顾了矢量量化的各种快速算法,指出其在应用到SAR原始数据压缩中的局限性。为了将矢量量化应用到SAR原始数据实时压缩,提出一种基于查表的矢量量化器的设计方案,其中整合了其他的矢量量化算法。最后用各种快速算法以及BAQ算法进行了对实际数据压缩的实验比较,证明本算法在不降低量化速度的基础上,提高了原始数据量化信噪比。

关键词：矢量量化合成孔径雷达原始数据压缩快速搜索算法

Detrital Zircons Transported from North china to Yangtze in the Middle Paleozoic:Implications for Tectonic Evolution in Central china

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Detrital Zircons Transported from North China to Yangtze in ...

Formation Age of the Sujiagou Komatiites in Western Shandong: Further Constraints from shrimp U-Pb Zircon Dating on Granitic Dykes

中国矿物岩石地球化学学会第十届学术年会

作者： SHE Zhen-bing,MA Chang-qian ,wan Yu-shengState Key laboratory of Geological Processes and Mineral Resource, and Faculty of Earth sciences, {2. University of Geosciences, Wuhan 430074,{2. beijing shrimp Center, beijing 10003.,{2.

＜正＞ The Qilian-Qinling-Dabie Orogen, the so-called Central china Orogenic Belt, presents the largest exposure of ultra-high pressure/ high pressure metamorphic rocks in the world. Being the most important geological boundary in china, it separates the North china Block （NCB） from the South china Block （SCB）. However, the timing of the amalgamation of the North and South

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 877-883页

作者： wan yusheng DONG Chunyan XIE Hangqian wanG Shijin beijing shrimp Center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Shandong Geological Survey Institute Jinan 250013China

Komatiites are presented as direct evidence for higher mantle temperatures during the Archean. In the North china Craton, komatiites with spinifex structure have been identified only at one locality, i.e. the Sujiagou area, western Shandong. They were considered as formed during the early Neoarchean mainly based on their association with supracrustal rocks considered to be that age. This study carried out shrimp U-Pb zircon dating on metamorphosed trondhjemitic and monzogranitic dykes intruding the Sujiagou komatiites, and they have magmatic zircon ages of 2.92.± 12.Ma and 2.86 ± 13 Ma respectively. This provides direct evidence that the komatiites formed during the early Neoarchean.

关键词： granitic dyke shrimp U-Pb zircon dating Sujiagou komatiite Neoarchean western Shandong

Protoliths of enigmatic Archaean gneisses established from zircon inclusion studies:Case study of the Caozhuang quartzite,***,china

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Geoscience Frontiers 2014年第4期5卷 445-455页

作者： Allen P.Nutman Ronni Maciejowski yusheng wan GeoQuEST Research Centre School of Earth & Environmental SciencesUniversity of Wollongong beijing shrimp Center Institute of GeologyChinese Academy of Geological Sciences

A diverse suite of Archaean gneisses at Huangbaiyu village in the North china Craton, includes rare fuchsite-bearing （Cr-muscovite） siliceous rocks - known as the Caozhuang quartzite. The Caozhuang quartzite is strongly deformed and locally mylonitic, with silica penetration and pegmatite veining common. It contains abundant 3880-3600 Ma and some Palaeoarchaean zircons. Because of its siliceous nature, the presence of fuchsite and its complex zircon age distribution, it has until now been accepted as a （mature） quartzite. However, the Caozhuang quartzite sample studied here is feldspathic. The shape and cathodoluminescence petrography of the Caozhuang quartzite zircons show they resemble those found in immature detrital sedimentary rocks of local provenance or in Eoarchaean polyphase orthog- neisses, and not those in mature quartzites. The Caozhuang quartzite intra-zircon mineral inclusions are dominated by quartz,

关键词： North china CratonCaozhuang quartziteZircon inclusionsEoarchaean rocksArchaean crustal evolution

Dating of zircon from high-grade rocks:Which is the most reliable method?

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Geoscience Frontiers 2014年第4期5卷 515-523页

作者： Alfred Krner yusheng wan Xiaoming Liu Dunyi Liu beijing shrimp Centre Institute of GeologyChinese Academy of Geological Sciences State Key laboratory of Continental Dynamics Department of GeologyNorthwest University

Magmatic zircon in high-grade metamorphic rocks is often characterized by complex textures as revealed by cathodoluminenscence （CL） that result from multiple episodes of recrystallization, over- growth, Pb-loss and modifications through fluid-induced disturbances of the crystal structure and the original U-Th-Pb isotopic systematics. Many of these features can be recognized in 2.dimensional CL images, and isotopic analysis of such domains using a high resolution ion-microprobe with only shallow penetration of the zircon surface may be able to reconstruct much of the magmatic and complex post- magmatic history of such grains. In particular it is generally possible to find original magmatic domains yielding concordant ages. In contrast, destructive techniques such as LA-ICP-MS consume a large volume, leave a deep crater in the target grain, and often sample heterogeneous domains that are not visible and thus often yield discordant results which are difficult to interpret. We provide examples of complex magmatic zircon from a southern Indian granulite terrane where shrimp lI and LA-ICP-MS analyses are compared. The shrimp data are shown to be more precise and reliable, and we caution against the use of LA-ICP-MS in deciphering the chronology of complex zircons from high-grade terranes.

关键词： Zircon datingHigh-grade rockshrimpLA-ICP-MS