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地学前缘 2009年第S1期16卷 171-171页

作者： Yalong Gao~1,Jingwen Mao~2.Huishou Ye~2.1.School of Earth sciences and Resources,china University of Geosciences(beijing),beijing 100083,china. 2.Institute of Mineral Resources,chinese academy of Geological sciences,beijing 10003.,china

The Shiyaogou deposit,located in Songxian,Henan Province,china,is a medium-sized Molybdenum deposit newly discovered in the East Qinling molybdenum *** in the altered Proterozoic Xionger Group,mineralization of the deposit consists of molybedenite disseminations and quartz -molybdenite veinlets and *** alteration is well developed and is composed of potassic alteration,silicification,sericitization,pyriti-

关键词： Re-Os dating porphyry molybdenum deposit Shiyaogou East Qinling lithospheric extension

生物乙醇柴油的特性及其在柴油发动机上的应用

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石油化工 2008年第3期37卷 209-215页

作者：贺泓石晓燕张长斌中国科学院生态环境研究中心北京100085

含氧燃料乙醇和生物柴油都是重要的生物质燃料,它们与柴油掺混使用可以降低柴油发动机尾气的污染物排放,特别是颗粒物的排放。在分别对乙醇柴油(乙醇和柴油的混合燃料)和生物柴油作为柴油替代燃料的研究进行总结的基础上,介绍了一种新... 详细信息

含氧燃料乙醇和生物柴油都是重要的生物质燃料,它们与柴油掺混使用可以降低柴油发动机尾气的污染物排放,特别是颗粒物的排放。在分别对乙醇柴油(乙醇和柴油的混合燃料)和生物柴油作为柴油替代燃料的研究进行总结的基础上,介绍了一种新的柴油混和燃料——生物乙醇柴油,即生物柴油-乙醇-柴油三组分混合燃料。综述了有关生物柴油-乙醇-柴油三组分物系的混溶特性和相行为,以及生物乙醇柴油在柴油发动机上应用时的燃料性质及其排放特性的最新研究结果。

关键词：生物质燃料乙醇生物柴油含氧燃料柴油替代燃料生物乙醇柴油

On the relationship between the postmidnight thermospheric equatorial mass anomaly and equatorial ionization anomaly under geomagnetic quiet conditions

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On the relationship between the postmidnight thermospheric e...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Jing Liu,Libo Liu,Biqiang Zhao,Jiuhou Lei,and Weixing Wan 1 beijing National Observatory of Space Environment,Institute of Geology and Geophysics,chinese {2. of sciences,beijing,china. 2.Also at State Key Laboratory of Space Weather,Center for Space Science and Applied Research,chinese {2. of sciences,beijing,china. 3 Graduate University of chinese {2. of sciences,beijing,china. 4 School of Earth and Space sciences,University of Science and Technology of china,Hefei,china.

[1]The equatorial mass anomaly(EMA) in the thermosphere and equatorial ionization anomaly(EIA) in the ionosphere are two interesting phenomena in low-equatorial latitude *** studies have shown that the EMA appears between 1000 and 2.00 local time(LT) and its location of trough is aligned with dip equator,indicating the plausible role of the EIA structure in the development of *** this report,we conducted a statistical study of the occurrence of postmidnight EMA and EIA on the basis of the CHAMP in situ measurements during *** results revealed that clear EMA and EIA structures are sometimes visible in the postmidnight sector(0100-0600 LT) during geomagnetic quiet periods(Kp2.00 LT to %at 0600 *** occurrence of postmidnight EIA presents a wave-like pattern;however,no salient feature appears for the longitudinal occurrence of *** EMA is more likely to occur at lower solar activity,whereas an opposite trend presents in the *** the basis of above results,our findings imply that a simple EIA-EMA cause-effect relationship does not hold in the postmidnight sector.

关键词：

STUDIES ON THE CHEMICAL CONSTITUENTS OF CLAUSENA LANSIUM (LOUR.) SKEELS Ⅳ THE STRUCTURAL ELUCIDATION OF SECO-AND SECODEMETHYL-CLAUSENAMIDE

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chinese Chemical Letters 1991年第10期2卷 775-776页

作者： Ming He YANG and Liang HUANG Institute of Materia Medica, chinese academy of Medical {2. 1 Xian Nong Tan St., beijing 100050

The spectral data and chemical properties of two new amides isolated from Clausena lansium led to the assignment of acyclic structures of C-6 and C-7. The absolute configurations of the two chiral carbons in C-6 were ... 详细信息

关键词： Chen LOUR SKEELS STUDIES ON THE CHEMICAL CONSTITUENTS OF CLAUSENA LANSIUM THE STRUCTURAL ELUCIDATION OF SECO-AND SECODEMETHYL-CLAUSENAMIDE

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基于无线局域网的多机器人通信系统性能分析

系统仿真学报 2009年第8期21卷 2219-2223,2238页

作者：李园原魁郑睿中国科学院自动化研究所北京100080

通信是多机器人之间进行信息交互并实现协作的基础。因此,了解与考虑多机器人系统的通信性能是构造具有实用价值的多机器人系统的前提。对基于IEEE802.11的无线通信协议的不同标准进行了研究,介绍了无线局域网(WLAN)的主要因素对多机器... 详细信息

通信是多机器人之间进行信息交互并实现协作的基础。因此,了解与考虑多机器人系统的通信性能是构造具有实用价值的多机器人系统的前提。对基于IEEE802.11的无线通信协议的不同标准进行了研究,介绍了无线局域网(WLAN)的主要因素对多机器人系统通信性能的影响,并通过大量实验测试了目前最常用的基于802.11g的WLAN的延时特性。本研究结果将对构建基于WLAN的多机器人通信系统有一定的参考价值。

关键词：多机器人通信 WLAN IEEE802.11 延时

Comparison of photovoltaic devices based on MEH-PPV with various molecular weights

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chinese Science Bulletin 2004年第21期49卷 2259-2261页

作者： KANG Bonan1,2. WANG Liduo1, YANG Yong1 & QIU Yong1 1. Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua Univer- sity, beijing 100084, china 2. State Key Laboratory on Integrated optoelectronics, Jilin University Region, Changchun 13002., china Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education Department of Chemistry Tsinghua University Beijing China State Key Laboratory on Integrated optoelectronics Jilin University Region Changchun China

Polymer photovoltaic devices based on poly (2. methoxy-5-(2. -ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH- PPV) with three weight-average molecular weights (Mw) have been fabricated with the device structure of ITO/PEDOT/ MEH-PPV/Ca/Ag, and the effect of the molecular weight on photovoltaic properties has been investigated. The experi- mental results show that the high molecular weight of MEH- PPV leads to low series resistance (Rs) and high short-circuit current. The low molecular weight of MEH-PPV leads to high shunt resistance (Rsh) and high open-circuit voltage. When the molecular weight is 6×105, the highest power con- version efficiency was observed.

关键词： MEHPPV 分子量光电器件载流子迁移率串联电阻并联电阻聚(2.甲氧基-5-(2.-乙基-乙氧基)-1,4-亚苯基乙烯撑)

Optimization approximation with separable variables for the one-way wave operator

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Optimization approximation with separable variables for the ...

中国科学院地质与地球物理研究所2.04学术年会

作者： Jing-Bo Chen and Hong Liu Institute of Geology and Geophysics,chinese academy of {2.,beijing,china Institute of Geology and Geophysics,chinese academy of {2.,P.O.Box 982.,beijing 10002.,china.

[1]An optimization approximation with separable vanables tor the one-way wave operator is presented in this *** new method approximates the one-way wave operator by products of functions in space variables and functions in wave number variables by means of optimization approximation with separable *** approximation enables us to use FFT algorithm which is independent of space variables while suffering no problem of branch points present in the generalized-screen *** TERMS:0902.Exploration Geophysics:Computational methods,seismic;0999 Exploration Geophysics:General or miscellaneous;32.0 Mathematical Geophysics:Numerieal ***:Chen. J.-B.,and ***(2.04),Optimization approximation with separable variables for the one-way wave operator,Geophys. ***.,31,L06613,doi:10.102./2.04GL01942.. *** [2.Consider the 3-D acoustic one-way wave equation for upcoming wave in the frequency-space domain

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Reaction-diffusion processes

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chinese Science Bulletin 1998年第17期43卷 1409-1420页

作者： CHEN Mufa beijing Normal University beijing 100875,{2. beijing Normal University Beijing China

The main progress made in the past dozen years or more in the study of reaction-diffusion (abbrev. RD) processes is surveyed. The processes are motivated from some typical models in the modern non-equilibrium statistical physics and consist of an important class of interacting particle systems which is currently an active research field in probability and mathematical physics. The models are concrete but as a part of the infinite-dimensional mathematics, the topic is quite hard. It is explained how new problems arise, and how some new ideas and new mathematical tools are introduced. Surprisingly, the mathematical tools produced from the study on the simple models then turn to have a lot of powerful applications not only in probability theory but also in other branches of mathematics. Nevertheless, the story is still far from finished, and some important open problems are proposed for further study.

关键词： Reaction-diffusion process ergodicity phase transitions coupling.

A Note on Cycles in Bipartite Graph

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A Note on Cycles in Bipartite Graph

中国运筹学会第六届学术交流会

作者： ZHUO XinjianInstitute of Systems Science, The academy of Mathematics and Systems sciences, {2. academy of sciences, beijing 100080

文献[wang,JGT,99]中已经证明:对任意的整数是一个的偶图,若G对任意的不相邻两点x∈V,y∈V都有,则对G的任意k条独立边e,…,e,都存在G的k个顶点不相交的圈C,…,C使得对所有的并且。然而,在这篇文章中,我们将证明“3k”并不是最好的界,它... 详细信息

文献[wang,JGT,99]中已经证明:对任意的整数是一个的偶图,若G对任意的不相邻两点x∈V,y∈V都有,则对G的任意k条独立边e,…,e,都存在G的k个顶点不相交的圈C,…,C使得对所有的并且。然而,在这篇文章中,我们将证明“3k”并不是最好的界,它可以被“3k-1”代替,并且我们还将给出一个例子说明“3k-1”是最好的界。

关键词：圈独立边偶图

Multiple Description Coding Based On Multiwavelets Transforming

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Multiple Description Coding Based On Multiwavelets Transform...

2.10 IEEE 2.d Symposium on Web Society

作者： Baobin Li School of Information Science and Engineering Graduate University of chinese academy of {2. beijing,100190,china Qing Ye china Center for Modernization Research chinese academy of Science beijing,100190,china

＜正＞Multiple description coding is a source coding for multiple channels such that a decoder which receives an arbitrary subset of the channels may produce a useful reconstruction,which is one of useful methods for solving the problem of packet losses in network *** this paper,on the basis of multiwavelet transform,a new method of multiple description coding will be presented,and experiments show it works ***,a parametrization of one kind of multifiler banks,which generate multiwavelets with some good properties,will be given.

关键词： Multiple description coding multiwavelet parametrization multifllter bank