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Proposal and prospects for the global Lower-Middle Cambrian boundary

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Progress in Natural Science:Materials International 2004年第12期 1-6页

作者： ZHAO Yuanlong 1*, YUAN Jinliang 2, PENG Shanchi 2, GUO Qingjun 3, ZHU Lijun 1, PENG Jin 1 and WANG Pingli 1(1. College of Resource and Environment of Guizhou University of Technology, Guiyang 550003, china 2. Nanjing institute of Geology and Palaeontology, chinese academy of sciences, Nanjing 210008, china 3. institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china) CollegeofResourceandEnvironmentofGuizhouUniversityofTechnology Guiyang550003China NanjinginstituteofGeologyandPalaeontology ChineseAcademyofSciencesNanjing210008China instituteofGeochemistry ChineseAcademyofSciencesGuiyang550002China

In recent years paleontologists have been working on the global stratotype section and standard point (GSSP) for the Lower Middle Cambrian boundary in North America, china, Morocco, Spain and Russia. Continually, they suggest the potential first appearance datum (FAD) of the Middle Cambrian, such as Oryctocephalus indicus, Ovatoryctocara granulata, Acadoparadoxides mureroensis, Hupeolenus and Arthricocephalus chauveaui as being relevant to the potential stratotype section for the Lower Middle Cambrian boundary. There are only a few trilobites distributed widely enough in the Early to Middle Cambrian connection, so virtually no trilobite(s) can act as the FAD for the global Middle Cambrian. The easily identified Oryctocephalus indicus is widely distributed in three realms of the global Cambrian. Its first appearance position is linked to the extinction of old species coevolution of new ones. It appears to be a comparatively good FAD of Middle Cambrian. The continuous and unbroken Wuliu section (Balang, Taijiang County, Guizhou Province, china) includes O. indicus and co occurs with many benthic and nektonic trilobites. The evolution of acritarchs in the section, the changed characteristics of trace elements (REE and C isotopes) are generally consistent with the evolution of trilobites both above and below the boundary. Strata above the boundary yield the famous Kaili Biota. The Wuliu section is easily accessible from a main highway.

关键词： Lower-Middle Cambrian boundary GSSP Taijiang Wuliu section Oryctocephalus indicus FAD (first appearance datum).

Rheological Behavior of Epoxy Resin Concentrated Dispersions

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chinese Chemical Letters 1999年第10期10卷 867-870页

作者： Zhen Zhong YANG Wei Wei WANG De Lu ZHAO Mao XU (1 institute of Chemistry. The chinese academy of sciences, Beijing 1000802 School of Basic Medical Science. Capital University of Medical Science, Beijing 100054) chinese Acad Sci Inst Chem Beijing 100080 Peoples R China Capital Univ Med Sci Sch Basic Med Sci Beijing 100054 Peoples R China

For the concentrated dispersions of epoxy resin prepared by phase inversion emulsification technique, the effects of solid content and temperature on the rheological behavior are studied. It is found that there exists reversible structural transition in concentrated dispersions subjected to shearing. The viscosity oscillation correlated with high viscoelasticity at lower stress is remarkable in highly concentrated dispersions. There exists storage modules overshot at higher stress during the dynamic stress time ramp test. This could provide some information on dynamics of structure changes during shear action. Besides, the effects of solid content and temperature on the relationship between tangent delta and frequency are essentially different.

关键词： rheological behavior waterborne dispersion bisphenol A epoxy resin

Japan＇s　Protectionist　Policy　of　Industries　and　Market：Operation　Mechanism　and　Network

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World Economy & china 1994年第1期2卷 12-17页

作者： $$$$(the institute of World Economics and Politics of the chinese academy ofSocial sciences.)Zhang Baozhen

Ｊａｐａｎ＇ｓＰｒｏｔｅｃｔｉｏｎｉｓｔＰｏｌｉｃｙｏｆＩｎｄｕｓｔｒｉｅｓａｎｄＭａｒｋｅｔ：ＯｐｅｒａｔｉｏｎＭｅｃｈａｎｉｓｍａｎｄＮｅｔｗｏｒｋ￥（Ｔｈｅａｕｔｈｏｒｉｓａｓｅｎｉｏｒｅｄｉｔｏｒｗｉｔｈｔｈ... 详细信息

Ｊａｐａｎ＇ｓＰｒｏｔｅｃｔｉｏｎｉｓｔＰｏｌｉｃｙｏｆＩｎｄｕｓｔｒｉｅｓａｎｄＭａｒｋｅｔ：ＯｐｅｒａｔｉｏｎＭｅｃｈａｎｉｓｍａｎｄＮｅｔｗｏｒｋ￥（ＴｈｅａｕｔｈｏｒｉｓａｓｅｎｉｏｒｅｄｉｔｏｒｗｉｔｈｔｈｅｉｎｓｔｉｔｕｔｅｏｆＷｏｒｌｄ...

关键词： Policy Protectionist and Market Industries Japan

Geochemistry of dissolved and suspended loads of the Xijiang River,china:Weathering processes and erosion rates

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Geochemistry of dissolved and suspended loads of the Xijiang...

A NEW LOW-COST DEMODULATOR FOR 2.4 GHZ ZIGBEE RECEIVERS

中国科学院地质与地球物理研究所2002学术年会

作者： Zhifang Xu~a,C.-Q.Liu~b and Hongxiang Zhang~c a.The institute of Geology and Geophysics,chinese academy of sciences,Beijing,china b.The institute of Geochemistry,chinese academy of sciences,Guiyang,china b.The institute of Geology and Geophysics,chinese academy of sciences,Beijing,china

This study focuses on the chemistry of the Xijiang River system,one of the major rivers in china,and constitute the first geochemical investigation of both suspended and dissolved loads of this river,in order to determine both chemical and mechanical erosion rates. Flowing in the south of china,the Xijiang River is the second largest river in china with respect to its discharge,after the Yangtze *** compared with the other large rivers of the world,the river is characterized by high major element *** dissolved major cations average 1.17,0.33,0.15 and 0.04 mmol l for Ca,Mg,Na and K,respectively,and the total cation concentrations(TZ+) vary between 2.2 and 4.4 meq *** high concentration of Ca and Mg,high(Ca+Mg)/(Na+K) ratio(7.9), enormous alkalinity and low dissolved SiO/HCO ratio(0.05) in river waters reveal the importance of carbonate weathering and erosion and relatively weak weathering and erosion of silicate over the river drainage basin. We propose a model based on mass budget equations,that allow the proportions derived from the different sources to be *** a consequence carbonate and silicate weathering rates can be estimated as well as the consumption of CO by weathering of each of these *** weathering rate are also estimated according to suspended *** elemental concentration of the river waters are corrected for rain inputs(mainle oceanic salts),they provide specific chemical erosion rates of 85-110 and 6-8.6 t/km/yr for carbonate and silicate,*** average atmospheric CO consumption results from silicate and carbonate weathering over the drainage basin are 41×10 and 216×10 mol C /yr. Mechanical erosion rate is 208 t/km/yr.

关键词： Xijiang River chemical erosion rates mechanical erosion rates atmospheric CO2 consumption

来源： cnki会议评论

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Journal of Electronics(china) 2009年第2期26卷 252-257页

作者： Yu Yunfeng Meng Xin Xiao Shimao Ma Chengyan Ye Tianchun institute of Microelectronics of chinese academy of sciences（CAS） Beijing 100029 china Hangzhou Microelectronics of chinese academy of Science Ltd. Hangzhou 310053 china

A new low-cost demodulator for ZigBee receivers satisfying requirements of IEEE802.15.4 standard is presented,which is designed for ISM 2.4 GHz band and based on Zero-IF *** demodulator extracts symbols directly from baseband signal rather than recovering PN code chips,so its structure is *** main techniques are used to improve the performance of *** is Phase-Axis Crossing Detector(PACD) which detects the phase correlation of baseband *** other is symbol synchronization and sampling clock correction *** result shows that this demodulator performance,Symbol Error Rate(SER) and Packet Error Rate(PER) meet IEEE 802.15.4TM standard requirements and the demodulator can handle frequency offset in excess of 200 kHz,involving a Zero-IF receiver with a Noise Figure(NF) lower than 17 dB,which is easily imple-mented in standard CMOS technology.

关键词： ZigBee Demodulator Minimum Shift Keying(MSK) Low-cost Symbol synchronization

ORGANOPHOSPHINE INITIATED REACTION OF PERFLUOROALKYL IODIDES WITH ALKENES

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chinese Chemical Letters 1990年第2期1卷 153-154页

作者： Wei Yuan HUANG Han Zhong ZHNG (Shanghai institute of Organic Chemistry,chinese academy of sciences,345 Lingling Lu,Shanghai 200032)

perfluoroalkyl iodides reacted with alkenes in acetonitrile solu- tion containing catalytic amount of organophosphine under mild condition to give the corresponding adducts in moderate to good *** was shown to involve... 详细信息

关键词： ORGANOPHOSPHINE INITIATED REACTION OF PERFLUOROALKYL IODIDES WITH ALKENES

The rearrangement of a steroid C20,C22-epoxide catalyzed by BF3·Et2O

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chinese Journal of Chemistry 1988年第1期6卷 70-76页

作者： LIU Xing-Ping PAN Xin-Fu LI Yu-Lin institute of Organic Chemistry,Lanzhou University,Lanzhou,LIANG Xiao-Tian institute of Materia Medica,chinese academy of Medical sciences,Beijing institute of Organic Chemistry Lanzhou University Lanzhou institute of Materia Medica Chinese Academy of Medical Sciences Beijing

The rearrangement of the C,C-epoxide（3a）catalyzed by BF·EtO was *** structures of 10 products obtained in this reaction（1a,1b,10,11,12 or 13,14,15,16,17 and 18）were determined and the mechanism discussed.

关键词： epoxide catalyzed by BF3 The rearrangement of a steroid C Et2O BF

Pool-formation and secondary change of biodegraded viscous oils:Case study of reservoir section in the ZhengjiaWangzhuang Oilfield, Jiyang Depression

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chinese Science Bulletin 2004年第S1期49卷 39-49页

作者： WANG Zhenqi, PENG Ping’an, YU Chiling, LU Hong, ZOU Yanrong, ZHANG Linye & LIU Junmin State Key Laboratory of Organic Geochemistry, Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china Department of Earth Science, Yangtze University, Jingzhou 434023, china Research institute of Geology, Shengli Oilfield Co. Ltd., SINOPEC, Dongying 257015, china chinese Acad Sci State Key Lab Organ Geochem Guangzhou Inst Geochem Guangzhou 510640 Peoples R China Yangtze Univ Dept Earth Sci Jinzhou 434023 Peoples R China Shengli Oilfeld Co Ltd Res Inst Geol SINOPEC Dongying 527015 Peoples R China

It is demonstrated by various geochemical indexes that the Zhengjia-Wangzhuang Oilfield with viscous crude oil in the Jiyang Depression has been sourced from the contribution of matured source rocks in the upper Es4. The principal cause leading to the densification of crude oils would be biodegradation, with the degradation level of crude oils being ranked as 2-8; vertically, the biodegradation level increases from the top to bottom of the oil column, with a distinctive biodegradation gradient occurring. Calculated parameters of sterane, terpane and methyl-phenanthrene have indicated that the source-rock’s maturity of crude oils and asphaltic sands ranges from 0.7 to 0.9, and based on the calculation of Easy Ro model, the temperature of hydrocarbon generation in the source rock would be within 120-140℃, which coincides with the measurements of reservoir inclusions. The measured homogenization temperature would represent the generation temperature of the source rock, and be fairly different from that

关键词： viscous oil biodegradation time of pool-formation time of degradation Jiyang Depression.

Variation　of　Satellite　Intensity　Factors　with　n　in　the　1s~2s∈lc→1s~23dnl→1s~2pnl　Dielectronic　Recombination　of　Lithiumlike　Ions

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原子与分子物理学报 1995年第1期 99-106页

作者： Zhao Libo(institute of Physics chinese academy of sciences P.O.Box 603 Beijing 100080)Li Shichang(institute Of Applied Physics and Computational Mathematics P. O. Box 8009 Beijing 100088)

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关键词： Autoionization Dielectronic recombination Satellite intensity factor