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Development of simple sequence repeats (SSR) markers of ramie and comparison of SSR and inter-SSR marker systems

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Progress in Natural Science:Materials International 2005年第02期15卷 42-47页

作者： ZHOU Jianlin1*, JIE Yucheng2., JIANG Yanbo2. ZHONG Yingli1, LIU Yunhai1 and ZHANG Jian1**(1. Department of Biochemistry and Molecular Biology, {2. of Life Science, Hunan normal university, Changsha 410081, China 2. Institute of Bast Fiber Crops, Chinese Academy of Agricultural Science, Changsha 410006, China) Department of Biochemistry and Molecular Biology College of Life Science Hunan Normal University Changsha 410081 China. Institute of Bast Fiber Crops Chinese Academy of Agricultural Science Changsha 410006 China

Ramie (Boehmeria nivea L.) is an important bast fiber crop. To study genetic background of this species, we isolated and characterized microsatellite markers of ramie. A genomic library containing inserts of rapid amplification of polymorphic DNA (RAPD) fragments was constructed, and screened by PCR amplification using anchored simple sequence repeats as primers. A total of 2. clones were identified as positives, and 13 microsatellite loci were found after sequencing. The polymorphism of these 13 microsatellite loci was examined and the utility of simple sequence repeats (SSR) and inter-SSR (ISSR) marker systems for genetic characterization compared using 19 selected ramie cultivars. Both approaches successfully discriminated the 19 cultivars which differed in the amount of polymorphism detected. The level of polymorphism detected by SSR was 95.0%, higher than that by ISSR (72.3%), but the average polymorphism information content (PIC) of ISSR (0.651) was higher than that of SSR (0.441). The higher PIC value of ISSR suggests that ISSR is more efficient for fingerprinting ramie cultivars than SSR markers. However, because the SSR loci are codominant, they are more suitable for determining the homozygosity levels of ramie, constructing linkage map, quantitative trait loci study of complex traits and marker-assisted selection.

关键词： ramie (Boehmeria nivea L.Gaud) simple sequence repeats inter-simple sequence repeats

Polyaniline Supported 12.Tungstosilicic Acid as the Catalyst for Acetals and Ketals Synthesis

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Journal of Wuhan university of Technology(Materials Science) 2009年第3期24卷 371-375页

作者：杨永金 PHILIPPE G Merle Hubei Key Laboratory of Pollutant Analysis & Reuse Technology College of Chemistry and Environmental Engineering Hubei Normal University Department of chemistry and Biochemistry Concordia University

A novel environmental friendly catalyst, H4SiW12.40/PAn was prepared and identified by FT-IR, XRD and TG/DTA. The optimal synthetic protocol was a PAn to H4SiW12.40 mass ratio of 1 ： 1, a 2. mL of methanol and a reaction time of 2.h at reflux. It was used in catalytic synthesis of ten important ketals and acetals with a high catalytic activity. With an aldehyde/ketone to glycol molar ratio of 1 ： 1.5 and a 1 wt% catalyst loading, the yields of ketals and acetals could reach 60.0%- 93.8 % after 1 h.

关键词： 12.tungstosilicic acid polyaniline acetal ketal catalysis

Preparation of Nanosized AlOOH and Its Application in Polymer-inorganic Nanocomposites

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Journal of Wuhan university of Technology(Materials Science) 2008年第5期23卷 638-643页

作者：廖海达 State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology college of chemistry and Ecological Engineer{2. Guangxi University for Nationalities Key Lab of Nonferrous Materials and New Processing Technology (Guangxi university Guilin University of Technology) Ministry of Education

With industrial grade Al（OH）3 as raw materials, the self dispersion nanosized AlOOH crystal powder were prepared by the sol-hydrothermal method. The results of XRD and TEM show that the nanosized AlOOH could automatically disperse to a single-dispersing state in water without surface modification, dispersant, additive and accessional conditions （ultrasonic wave dispersing, ball-mill dispersing）. The application results of the product indicate that the nanosized AlOOH can be composed into a toughened nanocomposites without surface modification. Accordingly, the self dispersion characteristic and mechanism of hydrothermal crystallization and charging composite dispersion of nanosized AIOOH are found, and a new technique of preparing polymer/inorganic nanocomposites is proposed, which is called blending compositing new techniques of sol even dispersing at auasi-homogeneous phase.

关键词： self dispersion nanosized AlOOH peptizing-hydrothermal method nanocomposites

A pulse radiolysis study on electron affinity of piperonal

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Science China chemistry 2005年第5期48卷 476-480页

作者： MA Jianhua1, LIN Weizhen2. WANG Wenfeng2.& YAO Side2.1. college of Biology Engineering, Jimei {2., Xiamen 36102., China 2. Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 2.1800, China college of Biology Engineering Jimei University Xiamen 361021 China

The piperonal electron affinity was studied using pulse radiolysis technique. The electron transfer reaction process between piperonal and anthraquinone-2.sulfate was observed in the pH 7 phosphoric acid salt buffer. The transient absorption spectra of electron transfer re-action between piperonal and anthraquinone-2.sulfate were obtained, and the initial proof of the electron transfer between electron donor and acceptor was provided directly. The one-electron reduction potential of piperonal was determined to be ?0.457 V.

关键词： piperonal, pulse radiolysis, one-electron reduction potential.

Nonlinear elastic waves in a monatomic chain with nonlinear interaction

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原子与分子物理学报 2002年第1期19卷 79-82页

作者： PAN Liu-xian 1, ZHOU Guang-hui 2. LI Shu-shen 3(1.Department of Physics, Yiyang Teacher's college, Yiyang 413049 2. Department of Physics, Hunan normal {2., Changsha 410081 3. National Laboratory for Supperlattice and Microstructure, Chinese Department of Physics Yiyang Teacher's College Yiyang 413049 Department of Physics Hunan Normal University Changsha 410081 中科院半导体所 National Laboratory for Supperlattice and Microstructure 北京 100083

Nonlinear wave equation for a one-dimensional anharmonic crystal lattice in terms of its microscopic parameters is obtained by means of a continuum approximation. Using a small time scale transformation, the nonlinear wave equation is reduced to a combined KdV equation and its single soliton solution yields the supersonic kink form of nonlinear elastic waves for the system.

关键词： Monatomic chain Continuum approximation Nonlinear elastic wave

Proton Conducting Composite Membranes from Sulfonated Polyether Ether Ketone and SiO_2

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Journal of Wuhan university of Technology(Materials Science) 2009年第1期24卷 95-99页

作者：张高文 college of chemistry and Environment Hubei University of Technology

Proton conducting composite membranes from sulfonated polyether ether ketone and SiO2.for direct methanol fuel cell （DMFC） application were prepared with sulfonated polyether ether ketone（SPEEK） and tetracethoxy silane（TEOS） by sol-gel method. The covalent crosslinking structure was formed between —SO3H of SPEEK via SiO2. The SEM images show that the interfacial compatibility of SPEEK and SiO2.is improved obviously and SiO2.disperses uniformly in the polymer matrix and the particle diameter of SiO2.does not exceed 40 nm. The proton conductivity of composite membranes decreases slightly compared with the SPEEK membrane while the methanol permeability and swelling of composite membrane are improved remarkablely owing to covalent cross-linking between —SO3H and SiO2..

关键词： direct methanol fuel cell sulfonated polyether ether ketone sol-gel method proton conductivity methanol permeability

Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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Science China chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 college of Materials Science and Engineering, Shandong {2. of Technology, Zibo 2.5049, China 2.Department of chemistry, Jilin {2., Changchun 13002., China college of Materials Science and Engineering Shandong University of TechnologyZibo 255049China Department of chemistry Jilin UniversityChangchun 130023China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Creep Characteristics of Crumb Rubber Modified Asphalt Binder

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Journal of Wuhan university of Technology(Materials Science) 2011年第1期26卷 118-120页

作者：王岚 college of Civil Engineering Inner Mongolia University of Technology

Crumb rubber modified asphalt containing 2. percent crumb rubber particles of 30 mesh has been examined by Scanning Electron Microscope （SEM） to observe the microcosmic appearance and the characteristic distribution of crumb rubber particles in asphalt. The SEM pictures reveal that the crumb rubber particles distribute evenly in the asphalt and they are compatible well with asphalt. The shear creep test of crumb rubber modified asphalt was carried out at -10 ℃ and 40 ℃ by Dynamic Shear Rheology （DSR）. The shearing deformation at different temperature and creep stiffness modulus curve at loading stage of crumb rubber modified asphalt have been measured. The stiffness modulus of crumb rubber modified asphalt is much temperature sensitive and it decays much quick at the early stage of loading than normal asphalt. The rate of decay of stiffness modulus is slow at the subsequent stage and stiffness modulus approaches to a stable value at the final stage at a higher temperature. In addition, Burgers model is suitable to describe and simulate experimental results of viscoelastic properties of the crumb rubber modified asphalt.

关键词： crumb rubber modified asphalt creep stiffness modulus rheology model model parameter

Cluster based node scheduling method for wireless sensor networks

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Science China(Information Sciences) 2012年第4期55卷 755-764页

作者： WANG Lei 1,2.WEI RuiZhong 2.& TIAN ZiHong 2.3 1 college of Software,Hunan university,Changsha 410082.China 2.Department of Computer Science,Lakehead university,Thunder Bay P7B 5E1,Canada 3 Mathematics and Information Science college,Hebei normal university,Shijiazhuang 050016,China college of Software Hunan University Department of Computer Science Lakehead University Mathematics and Information Science college Hebei Normal University

By researching on the node scheduling problem of m-covered and connected sensor networks,a new concept of two-hops-cluster is proposed in this paper,and based on it,a new distributed node scheduling algorithm THCNS for allocating all nodes in the sensor network into k(k≤m) different groups {0,1,...,k 1} is designed,without requiring location *** algorithm guarantees that each group to be connected and maintains the coverage ratio with high *** analysis and simulation results show that it has better performance than previous randomized scheduling scheme,and can prolong the lifetime of the sensor network effectively.

关键词： node scheduling lifetime wireless sensor network two-hops-cluster