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Plastid genome sequencing,comparative genomics,and phylogenomics:Current status and prospects

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Journal of Systematics and Evolution 2010年第2期48卷 77-93页

作者： 1Lei GAO 2.ing-Juan SU 1Ting WANG 1(key laboratory of Plant Germplasm Enhancement and Speciality Agriculture,{2. Botanical Garden,Chinese Academy of Sciences,{2. 430074,china) 2.state key laboratory of Biocontrol,School of Life Sciences,Sun Yat-sen University,Guangzhou 5102.5,china) (key laboratory of Plant Germplasm Enhancement and Speciality Agriculture Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China) (state key {2. of Biocontrol School of Life Sciences Sun Yat-sen University Guangzhou 510275 China)

More than 190 plastid genomes have been completely sequenced during the past two decades due to advances in DNA sequencing *** on this unprecedented abundance of data,extensive genomic changes have been revealed in the plastid *** is the most common mechanism that leads to gene order *** inversion events have been recognized as informative phylogenetic markers,such as a 30-kb inversion found in all living vascular plants minus lycopsids and two short inversions putatively shared by all *** loss is a common event throughout plastid genome *** genes were independently lost or transferred to the nuclear genome in multiple plant *** trnR-CCG gene was lost in some clades of lycophytes,ferns,and seed plants,and all the ndh genes were absent in parasitic plants,gnetophytes,Pinaceae,and the Taiwan moth *** parasitic plants have,in particular,lost plastid genes related to photosynthesis because of the relaxation of functional *** dramatic growth of plastid genome sequences has also promoted the use of whole plastid sequences and genomic features to solve phylogenetic *** phylogenomics has provided additional evidence for deep-level phylogenetic relationships as well as increased phylogenetic resolutions at low taxonomic ***,chloroplast phylogenomics is still in its infant stage and rigorous analysis methodology has yet to be developed.

关键词： chloroplast phylogenomics comparative genomics gene loss genome rearrangement plastid genome sequencing

Synthesis, Characterization and Flame-retardant Properties of Epoxy Resins and AACHH Composites

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Journal of wuhan University of Technology(Materials Science) 2009年第5期24卷 763-767页

作者：秦麟卿 state key {2. of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Flame retardant epoxy resins were prepared by a simple mixed method using ammonium aluminum carbonate hydroxy hydrate （AACHH） as a halogen-free flame retardant. The prepared samples were characterized by X-ray diffraction, thermogravimetric and differential scanning calorimetry, scanning electron microscope and limiting oxygen index（LOI） experiments. Effects of AACHH content on LOI of epoxy resins/AACHH composite and flame retardant mechanism were investigated and discussed. Results show that AACHH exhibites excellent flame-retardant properties in epoxy resin（EP）. When the content of AACHH was 47.4%, the LOI of EP reached 32.2.. Moreover, the initial and terminal decomposition temperature of EP increased by 48 ℃ and 40 ℃, respectively. The flame retarded mechanism of AACHH is due to the synergic flame retardant effects of diluting, cooling, decomposition resisting and obstructing.

关键词： epoxy resin(EP) flame retardant ammonium aluminum carbonate hydroxy hydrate (AACHH) composite

Research on theory and key technology of trusted computing platform security testing and evaluation

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Science china(Information Sciences) 2010年第3期53卷 434-453页

作者： ZHANG HuanGuo1,2. YAN Fei1,2. FU JianMing1,2. XU MingDi1,2. YANG Yang1,2. HE Fan1,2.& ZHAN Jing1,2.1School of Computer, wuhan University, wuhan {2., china 2.4} laboratory of Aerospace Information Security and Trusted Computing, Ministry of Education, wuhan {2., china School of Computer Wuhan University Wuhan China key laboratory of Aerospace Information Security and Trusted Computing Ministry of Education Wuhan China

Trusted computing has become a new trend in the area of international information security, and the products of trusted computing platform begin to be used in application. Users will not use the products of information security, unless it goes through the testing and evaluation. Here we concentrate on the testing and evaluation problem of trusted computing platform, begin with constructing proper formalization model of trusted computing platform for testing, and establish a mathematical chain of trust model based on SPA. Moreover, we give a verification method of composite characteristics and find the potential factors threatening the trusted system in the process of remote attestation through analysis. For trusted software stack, we study the problem of automatic generation of test case and propose an improved method of generating the random test case, to raise the quality of test case. Finally, we give a prototype system of trusted computing platform and the actual test data related. The result demonstrates that there exist some flaws in the architecture of the present TCG computing platform. At the same time, some flaws are found in the products of existing trusted computing platform, thus a basis is laid for the improvement and development of trusted platform technology and its products.

关键词： information security trusted computing trusted computing platform testing and evaluation

Dynamic Mechanical and Thermal Properties of Cross-linked Polystyrene/Glass Fiber Composites

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Journal of wuhan University of Technology(Materials Science) 2010年第5期25卷 780-784页

作者：朱泉峣陈文 School of Materials Science and engineering Wuhan University of Technology state key {2. of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology

Cross-linked polystyrene/glass fiber composites were fabricated using cross-linked polystyrene （CLPS） as matrix and E-glass fiber as the reinforcement. Surfaces of E-glass fibers were modified by vinyl triethoxysilane （VTES）, vinyl trimethoxysilane （VTMS） and γ-methacryloylpropyl trimethoxysilane （MPS）. The treated glass fibers were analyzed by fourier transform infrared spectroscopy （FTIR）. Dynamic mechanical thermal analysis （DMTA） and thermo-gravimetric analysis （TGA） were employed to investigate the effect of glass fibers surface modification on viscoelastic behavior and thermal properties. The morphology of fracture surfaces of various composites was observed by scanning electron microscopy （SEM）. The results revealed that these coupling agents were connected to the surfaces of the fibers by chemical bonding. Dynamic mechanical properties as well as thermal stability of the composites were improved considerablely, but to varying degrees depending on the fiber modification. The diversities of improvement of properties were attributed to the different interfacial adhesion between CLPS matrix and the glass fibers.

关键词： polymer-matrix composite cross-linked polystyrene (CLPS) fiber/matrix bond dynamic mechanical thermal analysis.

Fractal Analysis of Gas Diffusion Layer in PEM Fuel Cells

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Journal of wuhan University of Technology(Materials Science) 2006年第1期21卷 22-25页

作者：石英肖金生 state key {2. of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070ChinaSchool of Automation Wuhan University of Technology Wuhan 430070 China state key {2. of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070ChinaSchool of Automotive EngineeringWuhan University of Technology Wuhan 430070China

The aim of this study is to show how fractal analysis can be effectively used to characterize the texture of porous solids. The materials under study were carbon papers, the backing material of the gas diffusion layer （GDL） in Proton Exchange Membrane Fuel Cell （PEMFC）. The fractal dimensions were calculated by analyzing data from mercury porosimetry. The polytotrafluoroethylene （PTFE） treated carbon paper shows a significantly high fractal dimension value than pare sample, and the high fractal dimension signifies that the physical complexity of the pore surface is enhanced. The fractal dimension can be used as a valid parameter to monitor the textural evolution of the samples as the treatment progresses, as this behaves in a similar way to other textural parameters. The use of fractal analysis in conjunction with the results of classical characterization methods leads to a better understanding of textural modificatious in the processing of materials.

关键词： PEMFC gas diffusion layer fractal dimension mewury porosimetry

Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of wuhan University of Technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 College of Resources & Environment engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

Durinskia baltica(Dinophyceae),a newly recorded species and genus from china, and its systematics

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Journal of Systematics and Evolution 2011年第5期49卷 476-485页

作者： 1,2.Qi ZHANG 1~Guo-Xiang LIU 1~Zheng-Yu HU 1(state key {2. of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,Chinese Academy of Sciences,wuhan 430072.china) 2.Graduate University,Chinese Academy of Sciences,Beijing 100049,china) (state key {2. of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China)

A freshwater dinoflagellate was identified as Durinskia baltica(Levander) Carty & Cox by morphological characteristics,with the plate formula:Po,x,4,2.,6,5c,4s,5,*** was a newly recorded dinoflagellate genus for china with two anterior intercalary plates and six characteristic precingular *** sequences of the small and large subunit ribosomal DNA and internal transcribed spacer sequences for the dinoflagellate cells were obtained from field *** phylogenetic results indicated Durinskia species could cluster into a monophyletic group,which were distinct from Peridinium *** to morphological and molecular evidence,it was agreed that the genus Durinskia was separated from the genus Peridinium,which could be a polyphyletic *** addition,*** was an infrequent diatom-harboring dinoflagellate which was known to possess an endosymbiotic diatom or diatom-like *** phylogenetic analyses indicated that *** had a close affinity with Peridiniopsis penardii and ***,common freshwater bloom-forming species in china.

关键词： china Durinskia Durinskia baltica new record phylogeny.

Exact eigenstates for a class of models describing multiphoton processes in the presence of seven bosonic modes

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 649-657页

作者： ZHAN Zhiming1,LI Weibin2.YOU Jun2.XIE Xiaotao2.& YANG Wenxing2.1.state key {2. of Laser Technology,Huazhong University of Science and Technology,wuhan 430074,china 2.Department of Physics,Huazhong University of Science and Technology,wuhan 430074,china state key {2. of Laser Technology Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We present the analytical expressions of eigenstates and eigenenergies by using a parameter λ without the assumption of Bethe anzatz for three kinds of seven-bosonic-mode mixing models. The parameter is shown to be determined by the roots of a simple polynomial. We also demonstrate the exact analytical expressions of eigenstates and energies without any unknown parameter.

关键词： spectra, eigenstate, eigenvalue.

Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science china Earth Sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2. MA Dongsheng2. BAO Zhengyu3, PAN Jiayong2. CAO Shuanglin2.& XIA Fei2.1. School of Mathematics and Physics, china University of Geosciences, wuhan 430074, china 2. state key laboratory for Research of Mineral Deposits, Nanjing University, Nanjing 2.0093, china 3. Faculty of Earth Sciences, china University of Geosciences, wuhan 430074, china School of Mathematics and Physics China University of Geosciences Wuhan China state key {2. for Research of Mineral Deposits Nanjing University Nanjing 210093 China Faculty of Earth Sciences China University of Geosciences Wuhan China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2.0.4 m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.