检索结果-南通市图书馆

Synthesis, Crystal Structure and Second-order Optical Nonlinearity of 6-Nitro-[1,10]phenanthroline-1-ium Nitrate, [HphenNO2.^+NO_3^-

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2003年第5期22卷 533-538页

作者： CHEN Yu-Hong BEI Feng-Li YANG Xu-Jie LU Lu-De WANG Xin① (Materials Chemistry Laboratory, nanjing University of Science & technology, nanjing 2.0094, china) Materials Chemistry Laboratory Nanjing University of Science & Technology Nanjing 210094

The title compound [HphenNO2.+NO3- has been prepared and characterized by elemental analysis, electronic absorption spectroscopy, TG/DTA, IR, 1H and 13C NMR spectro- scopy. Single-crystal X-ray structure determination of the title compound was also carried out. It crystallizes in monoclinic, space group Cc with a = 13.861(3), b = 10.142.2., c = 8.732.(17) ? b = 103.70(3)? C12.8N4O5, Mr = 2.8.2., V = 1192.6(4) 3, Z = 4, Dc = 1.605 g/cm3 , F(000) = 592. (MoK) = 0.12. mm-1, R = 0.0439, wR = 0.112. and GOF =1.114. In the crystal lattice, the molecules create a network structure through hydrogen bonds. The second order optical non- linearity was performed by quantum chemical method, showing the title compound has higher molecular hyper polarizability value (?= 2..66×10-30 esu).

关键词： crystal structure 6-nitro-[1 10]phenanthrolin-1-ium nitrate characterization second-order non-linearity

THE MECHANICAL BEHAVIOR OF LABORATORY CROSS-WELD SPECIMEN AND ITS RELATION WITH THE PRACTICAL CASES AT ELEVATED TEMPERATURE

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1999年第1期12卷 85-91页

作者： S.T. TU, J.M. Gong and X. Ling nanjing University of chemical {2., nanjing 2.0009, china

In order to interpret the test results of crossweld specimens for application in practical welded components, the present paper studies the high temperature behavior of laboratory cross weld specimens in terms of the uniaxial material tests and numerical simulations. It is found that the crossweld specimen may be used for the high temperature strength assessment, but can hardly be used for life assessment of the practical welded components, which depends on the loading conditions of the components.

关键词： high temperature welding geometrical effect constitutive equation life prediction

Research progress in gecko locomotion and biomimetic gecko-robots

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第1期17卷 1-5页

作者： DAI Zhendong and SUN Jiurong ( Institute of Bio-inspired Structure and Surface Engineering, nanjing University of Aeronautics and Astronautics, nanjing 2.0016, {2. college of Life Sciences, Peking University, Beijing 100871, {2.) Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China college of Life Sciences Peking University Beijing 100871 China

Geckos are known for their excellent ability to climb walls and run on ceilings. Previous studies of the gecko's locomotive and adhesive mechanisms, its neuro-sensory and neuro-modulatory systems, its fabrication of artificial setae array, and other related developments, have inspired further research on gecko-based and gecko-like robots. Key research findings in this area are reviewed in the present paper.

关键词： gecko locomotion biomimetic modulation gecko-like robot.

Preparation of Material Surface Structure Similarto Hydrophobic Structure of Lotus Leaf

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of technology(Materials Science) 2008年第4期23卷 513-517页

作者： CAO Feng GUAN Zisheng LI Dongxu college of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

Nano/micro replication, a technique widely applied in the microelectronics field, was introduced to prepare the hydrophobic bionics microstructure on material surface. Poly（vinyl alcohol）（PVA） and polystyrene （PS） moulds of the mastoid microstructure on lotus leaf surface were prepared respectively by the nano/micro replication technology. And poly（dimethylsiloxane）（PDMS） replicas with the mastoid-like microstructure were prepared from these two kinds of polymer moulds. Scanning electronic microscope （SEM） was employed to investigate the morphology and microstructures on moulds and replicas. Both the static and dynamic contact angles between water droplet and PDMS replicas＇ surface were also measured. As a result, similar microstructure can be observed clearly on the surface of PDMS replicas and the static contact angle on PDMS replicas was enhanced dramatically by the existence of these microstructures.

关键词： hydrophobic bionics surface structure nano/micro replication

Negacyclic codes over Galois rings of characteristic 2.

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2012年第4期55卷 869-879页

作者： ZHU ShiXin 1,2.& KAI XiaoShan 1,2.1 School of Mathematics,Hefei University of technology,Hefei 2.0009,china 2.National Mobile Communications Research Laboratory,Southeast University,{2. 2.0096,china School of Mathematics Hefei University of Technology Hefei China National Mobile Communications Research Laboratory Southeast University Nanjing China

Abstract We investigate negacyclic codes over the Galois ring GR（2.,m） of length N = 2.n, where n is odd and k≥0. We first determine the structure of u-constacyclic codes of length n over the finite chain ring GR（2., m）[u]/〈u2. ＋ 1〉. Then using a ring isomorphism we obtain the structure of negacyclic codes over GR（2., m） of length N = 2.n （n odd） and explore the existence of self-dual negacyclic codes over GR（2., m）. A bound for the homogeneous distance of such negacvclic codes is also given.

关键词： negacyclic codes constacyclic codes Galois rings self-dual codes homogeneous distance

Adsorption separation of carbon dioxide,methane,and nitrogen on Hβand Na-exchangedβ-zeolite

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2008年第4期17卷 391-396页

作者： Xiaoliang Xu Xingxiang Zhao Linbing Sun Xiaoqin Liu State Key Laboratory of Materials-Oriented chemical Engineering,college of Chemistry and chemical Engineering,nanjing University of technology,nanjing 2.0009,Jiangsu,china State Key Laboratory of Materials-Oriented chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 Jiangsu China

Adsorption isotherms of carbon dioxide(CO),methane(CH),and nitrogen(N)on Hβand sodium exchangedβ-zeolite(Naβ)were volumetrically measured at 2.3 and 303 *** results show that all isotherms were of Brunauer typeⅠand well correlated with Langmuir-Freundlich *** sodium ions exchange,the adsorption amounts of three adsorbates increased,while the increase magnitude of COadsorption capacity was much higher than that of CHand *** selectivities of COover CHand COover Nenhanced after sodium ***,the initial heat of adsorption data implied a stronger interaction of COmolecules with Na~+ ions in Naβ.These results can be attributed to the larger electrostatic interaction of COwith extraframework cations in ***,Naβshowed a decrease in the selectivity of CHover N,which can be ascribed to the moderate affinity of Nwith Naβ.The variation of isosteric heats of adsorption as a function of loading indicates that the adsorption of COin Naβpresents an energetically heterogeneous *** the contrary,the adsorption of CHwas found to be essentially homogeneous,which suggests the dispersion interaction between CHand lattice oxygen atoms,and such interaction does not depend on the exchangeable cations of zeolite.

关键词： CO2 CH4 N2 adsorption separation Hβ Naβ

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

基于H_∞控制的主动队列管理算法

上海交通大学学报 2011年第8期45卷 1191-1195,1201页

作者：侯萍王执铨南京理工大学自动化学院南京210094 南京人口管理干部学院南京210042

针对网络参数的不确定性和链路带宽的时变性,设计了一种主动队列管理(AQM)算法.该算法将可获得的链路带宽作为标称值,而不可获得的未知时变链路带宽作为干扰信号,以状态空间的形式描述TCP/AQM模型,用时间域H∞控制方法解决网络拥塞问题.... 详细信息

针对网络参数的不确定性和链路带宽的时变性,设计了一种主动队列管理(AQM)算法.该算法将可获得的链路带宽作为标称值,而不可获得的未知时变链路带宽作为干扰信号,以状态空间的形式描述TCP/AQM模型,用时间域H∞控制方法解决网络拥塞问题.NS2.真结果表明,该算法在往返时间时变和具有扰动业务流情况下,能够快速收敛于期望队列长度,且性能优于已有的控制算法.

关键词： H∞控制网络拥塞往返时间不确定性参数

Silylated and acetylated β-cyclodextrins for gas chromatographic stationary phases

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University of technology 2001年第4期8卷 239-243页

作者： TANG Ke wen 1,2.,YI Jian ming 2.ZHOU Chun shan 1,ZHONG Shi an 1 (1. college of Chemistry and chemical Engineering, Central South University, Changsha 410083, {2. 2. college of Chemistry and chemical Engineering, Yueyang Normal University college of Chemistry and chemical Engineering Central South University Changsha China college of Chemistry and chemical Engineering Yueyang Normal University Yueyang China

Two new chiral stationary phases, 2.3 di O acetyl 6 O trimethylsilyl β cyclodextrin (DATBCD) and 2.6 di O trimethylsilyl 3 O acetyl β cyclodextrin(DTABCD), were synthesized, their structures were identified by means of infrared and NMR spectra. Capillary columns were coated with the two stationary phases by dynamic method. The chromatographic properties, and enantiomers separation, such as ketone, esters, alcohols and olefines, were investigated on the silylated and acetylated β cyclodextrin stationary phases. The experimental results show that the silylated and acetylated β cyclodextrins are suitable to be used as capillary gas chromatographic stationary phases, the relative polarity of DATBCD and DTABCD stationary phases is respectively 4143 and 392., the column efficiencies are respectively 3084 and 4198, and DATBCD is of stronger enantioselectivity than DTABCD, capacity factor of the first eluted enantiomer ( k 1) and separation factor(α)of α phenylethanol on DATBCD stationary phase are respectively 8.2. and 1.019.

关键词： capillary gas chromatography silylated and acetylated β-cyclodextrins enantiomeric separation

Bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2.and Cambrian Series 3

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,Lu Yao b,Hong Yang b a Department of Earth Sciences,nanjing University,nanjing 2.0093,{2. b college of Resource and Environmental Engineering,Guizhou University(Caijiaguan Campus),Guiyang 550003,{2. c nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,nanjing 2.0008,{2. Department of Earth Sciences Nanjing University Nanjing 210093 China college of Resource and Environmental Engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12.h and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South china,the Tarim Basin of china,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of Bathynotus from china,including *** which is widespread around the *** six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2.and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2.and Cambrian Series *** late appearance datum(LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2.and Cambrian Series 3.

关键词： Bathynotus Age Cambrian Series 2 Boundary Correlation