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Science china(Information Sciences) 2011年第3期54卷 674-682页

作者： GUO HongXiang , WU Jian, HONG Xiao Bin & LIN Jin Tong Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, beijing university of Posts and Telecommunications, beijing 100876,{3. 1. Key Laboratory of Information Photonics and Optical Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In order to effectively accommodate a wide variety of emerging and future applications with diverse requirements, an intelligent optical network capable of the rapid and resilient delivery of on-demand transparent transmission capacity is required. This paper investigates a multi-layer network architecture where a generalized multiple protocol label switching (GMPLS) controlled transparent wavelength switched optical network (WSON), as the transport core, collaborates with multiple client optical burst switching (OBS) networks distributed at the edge. Dynamic interworking mechanism as well as the related signaling/routing protocol ex- tensions for multi-QoS burst streams transmission among different OBS domains are proposed so as to provision an end-to-end (e2e) transparent optical connectivity with on-demand bandwidth to end-users. Moreover, the survivability of this transparent optical connectivity is also addressed. To validate the feasibility of this architecture, an integrated OBS/WSON network testbed was constructed, and stable e2e transparent connectivities were successfully demonstrated for an efficient multi-QoS burst streams transmission.

关键词： multi-layer network transparent optical network OBS WSON GMPLS

Synthesis of LaFeO_3.catalytic materials and their sensing properties

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Science china Chemistry 2009年第12期52卷 2106-2113页

作者： BAI ShouLi,SHI BingJie,MA LiJing,YANG PengCheng,LIU ZhiYong,LI DianQing & CHEN AiFan State Key Laboratory of Chemical Resource Engineering,College of Science,beijing university of Chemical Technology,beijing 100029,{3. 1. State Key Laboratory of Chemical Resource Engineering College of Science Beijing University of Chemical Technology Beijing 100029 China

LaFeO3.is a p-type semiconductor catalytic material of perovskite structure (ABO3.. Its magnetic and photocatalytic properties have been widely investigated,but the gas sensing properties are seldom reported,especially for toxic and noxious gases of NO2 and CO. The nanocomposites of LaFeO3.and LaFe1-xMgxO3.(x = 0.02,0.04,0.06) were prepared by various methods of the wet chemical process and their exact composition,crystal structures,grain sizes,specific surfaces,morphology and the electronic interaction between components were characterized by EDX,XRD,BET,SEM and XPS analysis. The sensors based on these nanocomposites have been fabricated to examine the sensing responses to gases,and the results show that these sensors exhibited high response to both oxidizing gas (NO2) and reducing gas (CO),and the response was greatly enhanced by the surface modification of MgO. The additive method,amount of additives,and their effects on the LaFeO3.structure and gas response have been analyzed and discussed by temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopic (XPS) analysis.

关键词： LaFeO3 NO2 CO sensing properties MgO-modified

THE MEASUREMENT OF PLASTIC DEFORMATION AND CRACK GROWTH IN CRACKED SPECIMENS BY SAM

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Acta Mechanica Solida Sinica 1994年第4期7卷 347-353页

作者： Sun Xuewei Li Mingzheng (Department of Engineering Mechanics,Tsinghua university,beijing 100084,P.R.china) Department of Engineering Mechanics Tsinghua University Beijing 100084 China

In this paper,scanning acoustic microscope(SAM) was used to obtain some characteristic photographs which explain the mesoscopic information of several cracked *** results on subsurface information of steel,nickel and aluminium were *** deformation and crack initiation were observed and *** length of crack propagation was *** is particularly suited to the study of many mesoscopic phenomena in material science because it can image mesoscopic subsurface feature without *** is revealed that SAM has a bright future in the field of mesomechanics.

关键词： SAM(scanning acoustic microscope) experiment mesomechanics crack

Resistance to chemical attack of bittern-resisting cement in high-bittern environment

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International Journal of Minerals,Metallurgy and Materials 2005年第5期 87-93页

作者： Yunbing Hou, Bingwen Wang, Yu Chen, Botao Zhang, and Lin Yu School of Resource & Safety Engineering, china university of Mining & Technology (beijing), beijing 100083. china

A new kind of bittern-resisting cement (BRC) was introduced. This material is based on the ternary cementitious system of clinker containing C4A3.S phase, high-activity ground granulated blast-furnace slag (GGBFS) and fly ash (FA). The hydration proc- ess and the hydrated products of BRC were studied by means of XRD, TG-DTA and SEM, and the resistance to chemical attack of BRC in high-bittern environment was also examined. The corrosion experiment in seven kinds of brines proved that BRC exhibits an excellent resistance to chemical attack of bittern. The corrosion resistance factors were calculated and all of them were greater than 0.96. It showed that BRC totally controls the cement-based material corrosion in brines from four aspects: (1) making full use of the dominant complementation effect of mineral materials; (2) diminishing the hydrated products easy to be attacked; (3. improving the microstructure of hardened cement mortar; (4) degrading the chemical attack of bittern.

关键词： bittern-resisting cement ternary cementitious system high-activity mineral materials resistance to chemical attack bit- tern corrosion resistance factor corrosion mechanism

Random Vibration Analysis of the Electronic Equipment Cabinet

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武汉理工大学学报 2006年第S2期28卷 709-713页

作者： LIU Yanping~1 LIU Dongqing~2 1.Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education,North china Electric Power university,beijing 102206 ,{3. 2.beijing university of Science and Technology,beijing 100083.{3. Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education North China Electric Power UniversityBeijing 102206China beijing university of Science and Technology Beijing 100083China

In order to understand the vibration characteristic of system structure of electronic equipment cabinet within the particular vibration frequency,the finite element analysis software-ANSYS is used to simulate the tests of random vibrations of the cabinet system and obtain the isopleths graph of deformation and stress of the *** can confirm maximum of deformation and stress of the cabinet and position *** more analysis of the frequency response curve,which can confirm harm- ful consequences random vibrations caused and weak link of the cabinet *** numerical simulation results are in good a- greement with the experimental *** shows that this research provides an efficient method for the anti-seismic design and the dynamic optimization design.

关键词： random vibrations test vibration characteristic numerical simulation finite element analysis electronic equipment cabinet ANSYS software

ESTIMATION OF REACTIVITY RATIOS OF METHYL ACRYLATE WITH N-ARYLMETHACRYL-AMIDE COPOLYMERS BY ~1H NMR METHOD

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Chinese Journal of Polymer Science 1990年第1期8卷 10-16页

作者： DING Youjun and QI Daquan (De partment of Chemistry, Pekinng university, beijing) Peking Univ China

The copolymerizations of methyl acrylate （MA） with different N- arylmethacrylamide （N-ArMA） were carried out in benzene solution by free radical initiation. The compositions of the copolymers were deter mined by;H NMR method. The monomer reactivity ratios were calculated by the Fineman-Ross （F-R） method. The reactivity ratios and the activity of various N-ArMA with MA were investigated.

关键词： Reactivity Ratios Copolymerization Methyl Acrylate N-Arylmethacrylamide ~1H-NMR Method.

Luminescence and energy transfer of Ce^(3.) and Dy^(3.) in BaLaB_9O_(16)

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Chinese Journal of Chemistry 1994年第4期12卷 328-333页

作者： HUANG, Xiao-HuaDepartment of Chemistry, Suzhou Railway Teacher’s College, Suzhou, Jiangsu 215009, chinaGUO, Feng-YuDepartment of Chemistry, Peking university, beijing 100871, china Department of Chemistry Suzhou Railway Teacher's College Suzhou Jiangsu 215009 China Department of Chemistry Peking University Beijing 100871 China

Under the excitation of UV light, the composition dependence of luminescence properties of Ce3. and Dy3. in BaLaB9O16 has been studied. The mechanisms of energy transfer from Ce3. to Dy3. and of concentration quenchin... 详细信息

关键词： Lanthanum cerium dysprosium luminescence energy transfer.

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土壤中稀土对有效氮形态分配和转化的影响

中国稀土学报 2004年第3期22卷 375-379页

作者：丁士明张自立梁涛孙琴中国科学院地理科学与资源研究所北京100101 安徽农业大学土化学安徽合肥230036 南京大学环境学院污染控制与资源化研究国家重点实验室江苏南京210093

在土壤旱作和淹水培养两种方式下 ,通过添加外源稀土研究了黄褐土中稀土对有效氮形态分配和转化的影响。结果表明 ,在旱培条件下 ,土壤中稀土含量的提高增加铵态氮和水解氮的含量 ,减少硝态氮的含量 ,两周内增加矿质态氮的含量 ,八周以... 详细信息

在土壤旱作和淹水培养两种方式下 ,通过添加外源稀土研究了黄褐土中稀土对有效氮形态分配和转化的影响。结果表明 ,在旱培条件下 ,土壤中稀土含量的提高增加铵态氮和水解氮的含量 ,减少硝态氮的含量 ,两周内增加矿质态氮的含量 ,八周以后则无显著影响 ;有效氮的含量在稀土含量较低时升高 ,高含量时则下降 ,实验确定外源稀土对旱培土壤有效氮作用的无观察效应浓度 (NOEC)为 44 3..8mg·kg- 1 。在淹水培养条件下 ,稀土含量较低时对土壤铵态氮和水解氮含量无显著影响 ,含量较高时则降低铵态氮和水解氮含量 ,外源稀土对淹水土壤铵态氮和水解氮含量影响的无观察效应浓度分别为 171.2 ,2 5 6.9mg·kg- 1 。分析表明 ,土壤中稀土含量的变化对氮素的影响在旱培条件下主要与稀土对土壤硝化过程作用有关 ,淹水条件下与稀土对土壤氨化过程作用有关。

关键词：土壤学氮素形态转化安全性评价黄褐土稀土

Infall and Outflow Activities in the Be star FY CMa

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Chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 514-524页

作者： Hui-Lai Cao National Astronomical Observatories, Chinese Academy of Sciences, beijing 100012 CAS-PKU Joint beijing Astrophysics Center, Peking university, beijing 100871 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 []CAS-PKU Joint Beijing Astrophysics Center Peking University Beijing 100871

Unusual activity of outflow mass motion connected with infall events was recorded for the B0.5 IVe star FY CMa in February 1987 from both archival IUE spectrograms of circumstellar N v resonance lines and optical spectra of Ha and HeI γ5876 A emission lines which showed inverse P Cygni-type profiles. We estimate the mass loss rate using ultraviolet Si IVresonance lines with expanding atmosphere modeling calculations, and describe how the radial pressure performs the dominant role in accelerating the stellar wind. We attempt to give a qualitative explanation for the activity observed for FY CMa in terms of circumstellar matter raining down to the star.

关键词： line: proffles - stars: activity - stars: emission-line Be -circumstellar matter - stars: mass-loss - ultraviolet: stars