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NEW CYCLOARTANE TRITERPENOID CIMISIDE E FROM CIMICIFUGA FOETIDA L.

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Chinese Chemical Letters 1993年第11期4卷 957-958页

作者： Cong Jun LIYing He LI Di Hua CHEN Pei Gen XIAO Institute of Medicinal Plant Development, Chinese academy of Medical sciences, Beijing 100094

This paper relates to the structural elucidation of a new cycloartane triterpene glycoside, namely cimiside E(1), which was newly isolatea from the rnizomes of Cimicifuga foetida L.. Based on spectral evidence, its st... 详细信息

关键词： Chen NEW CYCLOARTANE TRITERPENOID CIMISIDE E FROM CIMICIFUGA FOETIDA L

Synthesis and Structure of K_3Na_3〔MnMo_9O_(32)〕·6H_2O

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Chinese Journal of Structural Chemistry 1997年第1期16卷 64-67页

作者： YANG Xi--Ping SHAO Shi--Bao CHEN Chang-Zhang HUANG Xiao--Ying LIN Zhou--Bin Gao Dong--Shou (Fujian Institute of Research on the Structure of Matter,the Chinese academy of sciences, Fuzhou, 350002) Fujian Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou 350002 China

The title compound was synthesized from the manganese(Ⅶ ), titanium(Ⅲ ) and molybdate. It was crystallized as K3Na3[MnMo9O32,). 6H2O in the rhombohedral space group R32(155 # ), with a=b= 15. 521 (4), c= 12. 417 (6) A γ=120. 00 (1 )°. V= 2590. 1 (1 ) A 3, Z= 3, M.= 1778. 08, Dc= 3. 396g/cm3, λ(MoKa)=0. 71073A, μ= 42. 5 cm-1, F(000) ~ 2754 and the structure was determined by Xray diffraction methods, refined to a residual of 0. 048 for 113. independent observablereflections with I≥3σ(I). There are Potassium, sodium canons, [MnMo9O32]6- anion, and crystalline water molecules in the complex. The anion may be constructedfrom a hypothetical MnIVMo6 Anderson species by removing three alternate MoO6, octehedra and placing three MoO6, octahedra above and below the MnMo3 unit, thus the resulting structure has D3 symmetry.

关键词： synthesis crystal structure heteropoly compound

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, Guiyang 550003, China 2. Nanjing Institute of Geology and Palaeontology, Chinese academy of sciences, Nanjing 210008, China 3. State Key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 210008, China 4. Department of Geological Science, Ohio State University, Columbus, OH 43210, USA 5. Institute of Geochemistry, Chinese academy of sciences, Guiyang 550002, China) College of Resource and Environment of Guizhou University Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1934, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

CARBON ISOTOPE SHIFTS IN EARLY PROTEROZOIC CARBONATE STRATA, NORTH CHINA

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Scientia Geologica Sinica 1994年第3期 309-314页

作者： Zhong Hua (Institute of Geology, Chinese academy of sciences, Beijlhg 100029)Ma Yongsheng (Research Institute of Petroleum Exploration and Development, Beijing 100083)Wang Zhongcheng (Institute of Geology, Chinese academy of sciences, Beijing 100029)

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Synthesis of the Natural Products Resveratrol (Ⅰ) and Isorhapotogenin (Ⅱ)

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Chinese Chemical Letters 1998年第11期9卷 0-0页

作者： Ya Bing FENG Lin WANG Zhi Zhong ZHAO (Institute of Materia Medica, Chinese academy of Medical sciences Peking Union Medical Collage, Beijing, 100050)

We have synthesized two natural products, resveratrol Ⅰ and isorhapotigenin Ⅱ by 8 and 7 step reaction sequence, respectively. The synthetic products Ⅰ and Ⅱ were characterized by ***, 1H-NMR in comparison with th... 详细信息

关键词： Total synthesis, resveratrol isorhapotigenin

On Complex Oscillation Theory of Solutions of Some Higher Order Linear Differential Equations

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Journal of Mathematical Research with Applications 2012年第4期32卷 423-430页

作者： Jianren LONG 1,2 1.School of Mathematics and Computer Science,Guizhou Normal University,Guizhou 550001,P.R.China 2.academy of Mathematics and Systems Science,Chinese academy of sciences,Beijing 100190,P.R.China School of Mathematics and Computer Science Guizhou Normal University Guizhou 550001

In this paper,we shall use Nevanlinna theory of meromorphic functions to investigate the complex oscillation theory of solutions of some higher order linear differential *** that A is a transcendental entire function with ρ(A)<1/*** that k≥2 and f(k)+A(z)f=0 has a solution f with λ(f)<ρ(A),and suppose that A1=A+h,where h≡0 is an entire function with ρ(h)<ρ(A).Then g(k)+A1(z)g=0 does not have a solution g with λ(g)<∞.

关键词： complex differential equations entire function the growth of order the exponent of convergence of the zeros.

IntNMS:An Integrated Scheme for Network Measurement System Using Web Service

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IntNMS:An Integrated Scheme for Network Measurement System U...

Accretionary Tectonics in the Neoproterozoic History of the Larsemann Hills and Adjacent Areas, East Antarctica

2006 10th International Conference on Communication Technology（ICCT 2006）

作者： Wanming Luo Computer Network Information Center Chinese academy of sciences Beijing China Baoping Yan Computer Network Information Center Chinese academy of sciences Beijing China Jun Li Computer Network Information Center Chinese academy of sciences Beijing China

Network measurement is a key technology for network performance analysis and is becoming more and more important in the Internet research fields. In this paper we propose an integrated scheme for network measurement system called IntNMS, which is based on Web service technologies. The system architecture and modules are designed and implemented. IntNMS is able to integrate various measurement systems into a uniform platform which is highly flexible and scalable. In IntNMS, all kinds of measurement components are convenient to deploy. These merits are very important for the large-scale, distributed network measurement system. Additionally, we show the feasibility of IntNMS in network measurement through a case study.

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Continental Dynamics 1997年第1期 73-76页

作者： ZHAO Yue SONG Biao LIU Ping (Institute of Geology, Chinese academy of Geological sciences (CAGS), Beijng 100037, China) LIU Xiaohan (Institute of Geology, Chinese academy of sciences, Beijing 100029, China)

A NEW MECHANISM OF ULTRASOUND ATTENUATION IN SINTERED METAL POWDERS

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Acta Metallurgica Sinica(English Letters) 1996年第5期9卷 338-342页

作者： Z. C. Shen( International Centre for Materials Physics, Chinese academy of sciences, Shenyang 110015, China Suzhou Professional University, Suzhou 215002, China)

This paper analyzes the anomalous power-law dependence of the ultrasound attenuation on frequency by means of a percolation model. It was suggested that the anomaLous ultrasound attenuation is associated with strongly localized eigen modes (to be called fracton) in disordered systems. There exits a steplike increase in the density of vibrational states at crossover frequency ω(co).Computer simulation of vibration spectrum in disordered system is also reported. The density of vibrational states is consistent with the results of relevant experiment outlined above.

关键词： sintered metal powder percolating network fracton ultrasound Attenuation