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Correlation between the Standard Formation Enth alpy and the Path Index of Pyridine Derivatives

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wuhan University Journal of Natural Sciences 2000年第2期5卷 229-232页

作者： LI Liang chao 1 ,LIAO Gui ying 1,2.,JIANG Sheng bin 2.,WANG Ying xi 2.,SUN Ju tang 3 1. Departmnt of chemistry, Jingzhou Normal College, Jingzhou, China, 434100 2. hubei,{2., wuhan, China, 430074 Jingzhou Normal College Department of Chemistry Jingzhou China Jingzhou Normal College Department of Chemistry Jingzhou China hubei Research Institute of Chemistry Wuhan China hubei Research Institute of Chemistry Wuhan China wuhan University College of Chemistry Wuhan China (GRID:grid.49470.3e) (ISNI:***)

A formulated as △fH m ? (PPDs,g)=a+ΣbiPi + cifi is put forward for estimating standard formation enthalpies of pyridine-derivatives (PDDs), in which,P i is path index andc i f i is an amended term of interaction between substituent and N atom on pyridine ring. The Calculations based on the model were carried out for some pyridine-derivatives. The values of standard formation enthalpy calculated are consistent with those in literature.

关键词： Key words pyridine derivatives standard formation enthalpy path index

Surface modification of γ-Al_2._3 by sodium ions

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Chinese Science Bulletin 2001年第3期46卷 188-193页

作者： DENG Feng, YUE Yong, DU Youru, YE Chaohui, KONG Yuhua, WANG Guoxing & LI Xiaoding1. Laboratory of Magnetic Resonance and Atomic and Molecular Physics, wuhan institute of Physics and Mathematics, Chinese Academy of Sciences, wuhan 430071, China 2. hubei institute of chemistry, wuhan 430074, China Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China hubei institute of {2. Wuhan China

1H/2.Na double resonance NMR techniques were employed to study the modification of surface hydroxyls on Y-Al2.3 by sodium ions. 1H-2.Na cross polarization (CP) experiment can resolve three kinds of sodium cations that are closely associated with surface hydroxyl groups, while the signal of deposited salt-Na2.O3, which is not connected to surface hydroxyl groups, is completely suppressed. 1H{2.Na} spin echo double resonance experiments reveal the surface modification in more detail. At low Na+ coverage (5%, 10%), the acidic hydroxyl groups are preferentially coordinated with sodium ions, while both the acidic and the basic hydroxyl groups are accessible for sodium ions at highcoordination that causes proton of the OH groups to be easily dissolved, which is evidenced by the fact that with calcination temperature of the catalysts increasing, the acidic hydroxyl groups are preferentially removed and only the basic hydroxyl groups remain when the calcination temperature is raised to 600℃.

关键词： surface modification γ-Al2.3 NMR hydrodesulfu-rization catalyst.

The Evolution Trend of Optical Core Network

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China Communications 2008年第1期5卷 4-8页

作者： Mao Qian wuhan research {2. of Posts and Telecommunications,hubei, wuhan, 430074 China wuhan research {2. of Posts and Telecommunications Hubei Wuhan 430074 China

Optical network is the infrastructure of telecommunicationnetwork. More than 95% of information istransported over optical network in China, wherecore network is the main trunk. How to increase thebit rate of the single wavelength channel, raise thetotal capacity of the DWDM system, extend theoptical transportation distance of electrical repeaterfree of the DWDM system and optical network intelligenceare key problems demanding high *** evolution trend of the optical core network isdescribed with some examples in this paper.

关键词： optical core network DWDM UHS ULC ULH ASON

Mesozoic radiolarian chert from the middle sector of the Yarlung Zangbo suture zone,Tibet and its tectonic implications

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Science China Earth Sciences 2006年第4期49卷 348-357页

作者： ZHU Jie1,2. DU Yuansheng1, LIU Zaoxue2. FENG Qinglai1, TIAN Wangxue2. LI Jinping2.& WANG Changping2.1. Faculty of Earth Sciences,China University of Geology, wuhan 430074, China {2. institute of Regional Geology Survey, wuhan 430034, China 1. Faculty of Earth Sciences China University of Geology Wuhan 430074 China 2. hubei institute of Regional Geology Survey Wuhan 430034 China

Three radiolarian fauna, aged as the Middle-Late Triassic, Late Jurassic-Early Creta- ceous and Cretaceous radiolarian fauna, have been recognised in the radiolarian cherts from the middle sector of the Yarlung Zangbo suture zone, southern Tibet, China. The average contents of SiO2.in the radiolarian cherts of the Middle-Late Triassic and Late Jurassic-Early Cretaceous are 90.2.% and 92.58% respectively, with average ratios of Al/(Al+Fe+Mn) as 0.75 and 0.74 respectively, the average ratios of MnO/TiO2.as 0.36 and 1.2., the average ratios of Ce/Ce* as 1.15 and 1.03, and the average ratios of LaN/CeN as 0.85 and 0.93. These geochemical features indicate that both of them are biogenic, deposited in a continental margin basin. The SiO2.content of the Early Cretaceous radiolarian chert is 94.12., with the ratio of Al/(Al+Fe+Mn) as 0.59, ratio of MnO/TiO2.as 4.30, ratio of Ce/Ce* as 0.60, ratio of LaN/CeN as 1.59, which imply that the chert is biogenic and was deposited in a pelagic basin. The Middle-Late Triassic association of the radiolarian chert and turbidites as well as their geochemical characteristics indicates the existence of a strong rifting marginal basin in the belt of the Yarlung Zangbo River then. The association of radiolarian chert and bedded basalt indicate an initial Tethyan ocean basin in southern Tibet during the Late Jurassic-Early Cretaceous. The early Cretaceous radiolarian chert coexisting with pillow basalt in top of the ophiolite suite represents sediments from the oceanic Tethyan basin.

关键词： radiolarian chert, sedimentary geochemistry, Mesozoic, Yarlung Zangbo suture zone, Tibet.

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science China(Technological Sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3, WANG Guilan1 & ZHENG Qiguang2.1. School of Material Science and Technology, Huazhong University of Science and Technology, wuhan 430074, China 2. {2. of Laser Technology and Engineering, Huazhong University of Science and Technology, wuhan 430074, China 3. Mechanical Engineering College, hubei University of Technology, wuhan 430068, China 1. School of Material Science and Technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical Engineering College Hubei University of Technology Wuhan 430068 China 2. institute of Laser Technology and Engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Locating the Polar Cap Boundary of Postnoon Sector from Observations of 630.0 nm Auroral Emission at Zhongshan Station

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wuhan University Journal of Natural Sciences 2002年第1期7卷 59-64页

作者： Liu Li-gang 1, Ai Yong 1, Liu Rui-yuan 2. Yang Hui-gen 2.1. School of Electronic Information, wuhan University, wuhan 43007{2., China 2. Polar research institute of China, Shanghai 2.012., China wuhan University School of Electronic Information Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Polar research institute of China Shanghai China (GRID:grid.418683.0) (ISNI:***)

We studied the ground observations of 630.0 nm auroral emission at Zhongshan Station to determine the polar cap boundary with the latitudinal profile of emission intensity. The open-closed field time boundary is assumed to lie at the boundary between polar rain and plasma sheet precipitation. We assume that nonprecipitation-dependent sources of 630.0 nm emission cause a spatially uniform luminosity in the polar cap and that auroral zone luminosity is also spatially uniform. Therefore we determine the location of the polar cap boundary of postnoon sector from the auroral emission data each time by finding the best fit of the observations to a step function in latitude and we produce a time series of the location of the polar cap boundary. The average error of the practice in the paper is less than 0.8 degree.

关键词： polar cap boundary aurora Zhongshan Station

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern institute of Physics Chengdu 610041People's Republic of China Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 12. nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

Energy Efficient Beacon Discovering Scheme for Node Localization in Wireless Sensor Networks

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wuhan University Journal of Natural Sciences 2010年第4期15卷 303-307页

作者： LIU Xinxin1,2. ZHAO Erdun3, CHEN Kun2.1. School of Computer, wuhan University, wuhan 43007{2., China 2. wuhan Digital Engineering research institute, wuhan 430074, hubei, China 3. Department of Computer Science, Huazhong Normal University, wuhan 430079, hubei, China School of Computer Wuhan University Wuhan Hubei China wuhan Digital Engineering research {2. Wuhan Hubei China Department of Computer Science Huazhong Normal University Wuhan Hubei China

Efficient sensor node localization is a crucial part of many location-dependent applications that utilize wireless sensor networks (WSNs). To cope with the problem of insufficient bea-con node for localization,we design a beacon discovery protocol in this paper that helps the blind node to find beacons nearby and present an energy efficient scheme for the beacon that receives the request from a blind node to adjust its radio range. We obtain the relationship between the mean energy consumption with adjust-ment number by the mathematical analysis. Numerical results show that great energy saving is achieved when the optimal ad-justment number is adopted.

关键词： localization wireless sensor networks energy- efficient radio range adjustment

DETERMINATION OFTHE CRYSTALLINITY IN DIFFERENT TYPE POLY (OXYETHYLENE-STYRENE)BLOCK COPOLYMERS BY X-RAY DIFFRACTION METHOD

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Chinese Journal of Polymer Science 1989年第4期7卷 315-321页

作者：姚宁 hubei research institute of chemistry Wuhan

By means of the intensity theory of X-ray scattering and the two-phase concept of high polymer, the basic formula of the crystaUinity in block copolymers has been proposed after the corrections of atomic, temperature, absorption, Lorentz and polarization factor. Application of this method to different type poly (oxyethylene-styrene)block copolymers and the same type block copolymers with different EO contents indicates that the crystallinity in poly (oxyethylene-styrene ) block copolymers increases with the increase of the EO content and decreases in the order: PEO-PS-PEO>PEO-PS>PS-PEO-PS.

关键词： Crystallinity formula X-ray diffraction Block copolymers Poly (oxyethylene—styrene).