检索结果-南通市图书馆

Science china Chemistry 2010年第9期53卷 1946-1952页

作者： ZHI SanJun1,2,MEI HaiBo1,ZHANG GuangQian1,SUN Hao1,HAN JianLin1,LI GuiGen4 & PAN Yi1,3 1 School of Chemistry and Chemical Engineering,nanjing university,nanjing 210093,china 2 School of Chemistry and Chemical Engineering,Huaiyin Normal university,Huai’an 221003,china 3 state Key laboratory of Coordination Chemistry,nanjing university,nanjing 210093,china 4 department of Chemistry and Biochemistry,Texas Tech university,Texas 79409-1061,USA School of Chemistry and Chemical Engineering Nanjing University Nanjing China School of Chemistry and Chemical Engineering Huaiyin Normal University Huai’an China department of Chemistry and Biochemistry Texas Tech University Texas USA state Key laboratory of Coordination Chemistry Nanjing University Nanjing China

The combination of benzamide and NCS was found to be an efficient nitrogen/halogen source for aminohalogenation of β-*** reaction was convenient to carry out by using 4-dimethylaminopyridine as the catalyst,resulting in vicinal dichlorinated haloamino nitroalkanes with opposite regiochemistry to that generated from other electron-deficient olefins observed *** reaction proceeded smoothly at room temperature with good yields and excellent regioselectivities.A mechanism involving a chloronium intermediate was proposed to explain the resulting *** current system explored a new type of nitrogen sources for aminohalogenation of functionalized olefins.

关键词： aminohalogenation benzamide β-nitrostyrenes DMAP haloamides

A restudy of Oryctocephalus indicus (Reed,1910)

在线全文

学校读者我要写书评

暂无评论

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.

Post-earthquake assessment of building damage degree using LiDAR data and imagery

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2008年第S2期51卷 133-143页

作者： LI ManChun1,CHENG Liang1,2,GONG JianYa2,LIU YongXue1,CHEN ZhenJie1,LI FeiXue1,CHEN Gang1,CHEN Dong1 & SONG XiaoGang3 1 department of Geographic Information Science,nanjing university,nanjing 210093,china 2 state Key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 430079,china 3 state Key laboratory of Earthquake Dynamics,Institute of Geology,china Earthquake Administration,Beijing 100029,china department of Geographic Information Science Nanjing University Nanjing China state Key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China state Key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing China

Various methods have been developed to detect and assess building's damages due to earthquakes using remotely sensed *** the launch of the high resolution sensors such as IKONOS and QuickBird,it becomes realistic to identify damages on the scale of individual *** the low accuracy of the results has often led to the use of visual interpretation ***,it is very difficult to estimate the degree of building damage(*** damage,moderate damage,or severe damage) in detail using the existing ***,a novel approach integrating LiDAR data and high resolution optical imagery is proposed for evaluating building damage degree *** approach consists of two steps:3D building model reconstruction and rooftop patch-oriented 3D change ***,a method is proposed for automatically reconstructing 3D building models with precise geometric position and fine details,using pre-earthquake LiDAR data and high resolution ***,focusing on each rooftop patch of the 3D building models,the pre- and post-earthquake LiDAR points belonging to the patch are collected and compared to detect whether it was destroyed or not,and then the degree of building damage can be identified based on the ratio of the destroyed rooftop patches to all rooftop *** novelty of the proposed approach is to detect damages on the scale of building's rooftop patch and realize quantitative estimation of building damage degree.

关键词： post-earthquake assessment building damage degree rooftop patch LiDAR imagery

Spontaneous Correlation of Crystallographic Orientations in Crystallite Aggregation in Two-dimensions: Physical Origin and Its Influence on Pattern Formation

在线全文

学校读者我要写书评

暂无评论

Spontaneous Correlation of Crystallographic Orientations in ...

Scheme for Entanglement Concentration of Unknown Multiparticle Greenberger-Horne-Zeilinger or W Class states

2003年纳米和表面科学与技术全国会议

作者： Mu Wang laboratory of solid state microstructures and department of physics, nanjing university, nanjing 210093 and International Center for Quantum Structures, Chinese Academy of Sciences, Beijing 100080

Self-organization of microstructures in interfacial growth has been intensively studied in the past decades. Ordered structures can be spontaneously generated in the interfacial growth by stress-induced instability. It is well-known when a crystalline layer is coherently adsorbed on a substrate with different lattice parameters, the mismatch energy is high and the system tends to escape to a state with lower energy. Instead of generating defects, such as misfit dislocations, the strained film can be relaxed by surface deformation, where periodic hills and

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Communications in Theoretical physics 2007年第12期48卷 1025-1028页

作者： SONG Wei Hefei national laboratory for Physical Sciences at Microscale and department of Modern physics,university of Science and Technology of china,Hefei 230026,china Hefei national laboratory for Physical Sciences at Microscale and department of Modern physics University of Science and Technology of China Hefei 230026 China

We present,two schemes for concentrating unknown nonmaximally entangled Greenberger Horme-Zeilinger(GHZ) or W class *** first scheme for concentrating the nonmaximally entangled GHZ state is based on linearoptical *** second scheme for concentrating the W class states can be applied to a wide variety of atomic *** of our schemes are not postselection ones and are within the current technologies.

关键词： entanglement concentration GHZ class states W class states

Mechanical behavior of a shelter system based on cable-strut structures

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang university-Science A(Applied physics & Engineering) 2012年第12期13卷 895-903页

作者： Jian-guo CAI1,2,Ya ZHOU1,Jian FENG1,2,Yi-xiang XU3 (1Key laboratory of C&PC Structures of Ministry of Education,Southeast university,nanjing 210096,china) (2national Prestress Engineering Research Center,Southeast university,nanjing 210096,china) (3department of Civil Engineering,Strathclyde university,Glasgow,UK) Key laboratory of C&PC Structures of Ministry of Education Southeast University Nanjing China national Prestress Engineering Research Center Southeast University Nanjing China department of Civil Engineering Strathclyde University Glasgow UK

A shelter system based on cable-strut structures,consisting of compressive struts and high-tensile elements,is described in this *** deployment of the shelter is achieved by tightening inclined *** cables are used to terminate the *** state of self-stress of the cable-strut structures in the fully deployed configuration is given,and the minimum strut length and the maximum load design of the shelter are *** mechanical behavior of the system was studied under symmetrical and asymmetrical load *** results show that the shelter in the deployed configuration satisfies the ultimate limit and the serviceability limit state ***,the stability of the cable-strut system is investigated,considering the effect of imperfections on the buckling of the *** conclude that the influence of imperfections based on the consistent imperfection mode method is not significant.

关键词： Foldable structures Cable-strut structures Mechanical behavior Self-stress Stability

High Density Multiplication of Graphoepitaxy Directed Block Copolymer Assembly on Rectangle Lattice Template

在线全文

学校读者我要写书评

暂无评论

High Density Multiplication of Graphoepitaxy Directed Block ...

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

中国化学会第27届学术年会

作者： Yu-qiang Ma national laboratory of solid state microstructures, nanjing university, nanjing 210093, china & Center for Soft Condensed Matter physics and Interdisciplinary Research, Soochow university, Suzhou 215006, china

＜正＞Generating high density-multiplied nanopatterns through the directed self-assembly of block copolymers （BCPs） will significantly influence the current microelectronics and storage industries

关键词： Block Copolymer High Density Multiplication of Graphoepitaxy Self Assembly

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Science china Earth Sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3 1 state Key laboratory of Palaeobiology and Stratigraphy,nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,nanjing 210008,china 2 Graduate School of Chinese Academy of Sciences,Beijing 100049,china 3 department of Science and Technology,Bryant university,Smithfield RI 02917,USA state Key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of Chinese Academy of Sciences Beijing China department of Science and Technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

在线全文

学校读者我要写书评

暂无评论

制备可见光致发光硅量子阱的激光晶化技术

中国激光 1994年第2期21卷 126-130页

作者：黄信凡陈坤基徐骏南京大学固体微结构物理实验室南京大学物理系

我们利用Ａｒ＋激光辐照ａ－Ｓｉ：Ｈ／ａ－ＳｉＮｘ：Ｈ多量子阱结构材料，使ａ－Ｓｉ：Ｈ阱层晶化。在该样品中成功地观察到室温可见光致发光现象，研究了阱层厚度和激光辐照功率对光致发光峰峰位及半高宽的影响。

关键词：非晶硅量子阱晶化激光辐照

CHOLESTERIC LIQUID CRYSTALLINE CHARACTER ON THE SURFACE OF CHITOSAN/POLYACRYLIC ACID COMPOSITES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2001年第3期19卷 247-253页

作者： Yan-ming Dong Yu-song Wu Mian Wang department of Materials Science & state Key laboratory for Physical Chemistry of solid Surfaces, Xiamen university Xiamen 361005, china 厦门大学固体表面物理化学国家重点实验室福建厦门

The cholesteric liquid crystalline structure in chitosan/polyacrylic acid composite films was studied by surface techniques. A periodical lamellar-like structure was observed in the permanganic acid etched film surface by both scanning electron microscopy (SEM) and atomic force microscopy (AFM), instead of the thumb-print texture which can be detected with polarized optical microscopy. It is suggested that the periodical lamellar-like structure is induced by the etching selectivity between cholesteric layers due to different molecular arrangement on the film surface. Four kinds of perpendicular disclinations, i.e. chi --> tau (-) + lambda (+), chi --> lambda (-) + tau (+), chi --> tau (-) + tau (+) and chi --> lambda (-) + lambda (+) were found in the composite films from SEM observations. The smallest periodicity of lamellar-like structure (equals to half pitch) is 20 similar to 40 nm measured with AFM.

关键词： chitosan cholesteric order liquid crystalline fingerprint texture lamellar structure SEM AFM