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Overview of Rim2/Hipa transposon superfamily:Structure, distribution, transposition and utilization

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Progress in Natural science:materials International 2008年第4期18卷 375-379页

作者： Pingfang Tian a, Zuhua He b a college of Life science and technology, beijing university of chemical technology, beijing 100029, china b Shanghai Institute of Plant Physiology and Ecology, Shanghai Institute for Biological sciences, Chinese Academy of sciences, Shanghai 200032, china college of Life science and technology Beijing University of Chemical Technology Beijing 100029 China Shanghai Institute of Plant Physiology and Ecology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The rice Rim2/Hipa is a unique transposon superfamily in Oryza genomes, which can be transcriptionally activated by the infection of the rice blast pathogen Magnaporthe grisea and its elicitors. Rim2/Hipa elements belong to En/Spm family, with perfect terminal inverted repeats in both ends, direct and inverted sub-terminal repeats, and 3-bp target site duplication upon insertion. Intriguingly, the typical ’CACTG’ end sequences in the terminal inverted repeats of most Rim2/Hipa elements distinguish them from previously reported CACTA elements, such as En/Spm, Tam1, and Tgm1, which harbor ’CACTA’ sequence in their terminal inverted repeats. In particular, the plentiful Rim2/Hipa elements unevenly distribute over all 12 chromosomes and make up at least 1% of the entire genome. Southern hybridization revealed the existence of Rim2/Hipa elements in all rice varieties examined and the Rim2/Hipa core sequence is unique to rice genomes. Evidence derived from sequence analysis indicated the occurrence of transposition events during the long evolution. The abundance and insertion polymorphisms suggested their applications as novel molecular marker in rice fingerprinting and fine chromo- some mapping. This paper aims at outlining the Rim2/Hipa elements with respect to their structure, distribution, transposition and utilization.

关键词： Rim2/Hipa elements Structure Distribution Transposition Utilization

Synthesis of spherical Li1.167Ni0.2Co0.1Mn0.533O2 as cathode material for lithium-ion battery via co-precipitation

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Progress in Natural science:materials International 2012年第2期22卷 126-129页

作者： Xiangqing Liu,Zhimeng Guo Advanced material&technology Institute,university of science and technology beijing,china Advanced material & technology Institute University of Science and Technology Beijing China

xLi2MnO3(1 x)LiNi0.4Co0.2Mn0.4O2(x=0.5)powders were synthesized from co-precipitated spherical metal carbonate,Ni0.2Co0.1Mn0.533(CO3)*** has been found that the preparation of metal carbonate was significantly dependent on synthetic conditions,including the coprecipitation temperature,kind of precipitator,and stirring *** results of SEM showed that the shape of precursor powders was *** the final product,Li1.167Ni0.2Co0.1Mn0.533O2,was also significantly uniform due to the homogeneity of the metal carbonate precursor,Ni0.2Co0.1Mn0.533(CO3)x,.Li1.167Ni0.2Co0.1Mn0.533O2 has a-NaFeO2 layered structure,as confirmed by XRD *** average particle size was about 10 mm in diameter and the particle size distribution was relatively *** results of XRD and chemical analysis showed that the synthesized Li1.167Ni0.2Co0.1Mn0.533O2 had lower cation mixing and good layered structure,and the chemical composition is almost *** properties during charge and discharge were *** the voltage range of 2.0-4.8 V,the discharge capacity of Li1.167Ni0.2Co0.1Mn0.533O2 was 340 mAh/g.

关键词： Cathode material Co-precipitation Li1.167Ni0.2Co0.1 Mn0.533O2 Lithium-ion battery

Statistical study of cement additives with and without chloride on performance modification of Portland cement

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Progress in Natural science:materials International 2011年第3期21卷 246-253页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of materials-Oriented chemical engineering,college of material science and engineering, Nanjing university of technology,Nanjing 210009,china State Key Laboratory of materials-Oriented chemical engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The effectiveness of cement additives with and without chloride on the fluidity and the strength development of Portland cement was compared by using statistical full factorial *** experimental results show that the cement additive containing CaCl2and Ca(NO3)2can enhance early strength of cement ***,Ca(NO3)2is less effective than CaCl2even if it is combined with other organic chemicals such as alkanolamine and *** significant difference is found between CaCl2and Ca(NO3)2influencing the fluidity and 28 d strength of *** fluidity is determined by saccharide and its interaction with *** 28 d strength enhancement is determined by *** fluidity as well as the mechanical performance of treated cement can be significantly improved by combining Ca(NO3)2with TIPA and saccharide.

关键词： Portland cement cement additive accelerator type fluidity strength development full factorial design

Heat capacity and thermodynamical properties of the crystal of [RE_2(Glu)_2(H_2O)_8](ClO_4)_4·H_2O (RE = Nd, Eu, Dy)

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science china Chemistry 2009年第7期52卷 862-867页

作者： WU XinMin1, LI Wei1, TAN ZhiCheng2 & QU SongSheng3 1 Department of chemical engineering, beijing Institute of Petro-chemical technology, beijing 102617, china 2 Thermochemistry Laboratory, Dalian Institute of chemical Physics, Chinese Academy of sciences, Dalian 116023, china 3 college of Chemistry and Molecular science, Wuhan university, Wuhan 430072, china Department of chemical engineering Beijing Institute of Petro-chemical Technology Beijing 102617 China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China college of Chemistry and Molecular science Wuhan University Wuhan 430072 China

Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 298.15 K.

关键词： complex of rare earth, [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy Glu = glutamic acid), low-temperature heat capacity, standard enthalpy of formation

Construction and characterization of the transformation-competent artificial chromosome (TAC) libraries of Leymus multicaulis

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science china(Life sciences) 2008年第7期51卷 604-613页

作者： XU YueYu 1,2,3,ZHOU YuLei 4,5 ,SONG LinLin 6 ,ZHANG Yan 3 &ZHAO MaoLin 1 1 beijing Agro-Biotechnology Research Center,beijing Academy of Agriculture and Forestry science,beijing 100097,china 2 Department of Chemistry and chemical engineering,Hunan Institute of engineering,Xiangtan 411104,china 3 college of Life science,Capital Normal university,beijing 100037,china 4 college of Life science,Zhongkai university of Agriculture and technology,Guangzhou 510225,china 5 college of Grassland science,Gansu Agricultural university,Lanzhou 730070,china 6 Department of Biology,Henan Institute of science and technology,Xinxiang 453003,china 1. beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Science Beijing 100097 China 2. Department of Chemistry and chemical engineering Hunan Institute of Engineering Xiangtan 411104 China 3. college of Life science Capital Normal University Beijing 100037 China 4. college of Life science Zhongkai University of Agriculture and Technology Guangzhou 510225 China 5. college of Grassland science Gansu Agricultural University Lanzhou 730070 China 6. Department of Biology Henan Institute of Science and Technology Xinxiang 453003 China

Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in *** order to clone genes highly tolerant to barley yellow dwarf virus(BYDV),Aphids,drought and salt from Leymus multicaulis,the two TAC genomic libraries I and II were constructed in vector pYLTAC17 and pYLTAC747H/sacB,which contain about 165000 and 236000 recombinant clones *** genome coverage of the two libraries was totally estimated to be about 3―5 haploid genome equivalents,as size selection of genomic DNA fragments was approximately from 9 to 300 *** of the genomic libraries were collected as bulked pools each containing 500 clones or so,stored in twelve 96-deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3×3 pattern using a GeneTAC?G3 arraying robot after being transferred manually into three 384-well *** 2501 and 2890 clones of Library in pYLTAC17 and in pYLTAC747H/sacB were stored individually in fourteen 384-well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6×6 pattern after a replication of *** positive clones were detected by using the probe glutahione reductase gene of *** libraries constructed here can be used to isolate genomic clones containing target genes,and to carry out genome walking for positional *** the target TAC clones were isolated,they could be immediately transferred into plant genomes with the Agrobacterium system.

关键词： Leymus multicaulis megabase-size DNA transformation-competent artificial chromosome(TAC) genomic library

Recent progress and application of materials life cycle assessment in china

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Progress in Natural science:materials International 2011年第1期21卷 1-11页

作者： Zuo-ren NIE,Feng GAO,Xian-zheng GONG,Zhi-hong WANG,Tie-yong ZUO college of materials science and engineering,beijing university of technology,beijing 100124,china college of materials science and engineering Beijing University of Technology Beijing 100124 China

Life cycle assessment(LCA) is a technique for systematically analyzing the environmental impacts and resources used throughout a target’s life cycle,*** raw material acquisition,via production and use phases,to waste *** is an effective tool that gives a detailed information of environmental profiles of a material or a *** importantly,the value of life cycle thinking lies in its ability to provide the decision-making basis for sustainable development,making the products, industries and even the whole industry chain act more in line with the principles of sustainable *** recent developments of LCA methods and applications of materials life cycle assessment in china were *** the sections on LCA methodology,the data quality analysis,the impact of land use and abiotic resource depletion as well as the weakness in life cycle impact assessment were *** relation to the applications,the Chinese materials database(SinoCenter Database) and several representative case studies such as life cycle analysis of civilian buildings and metal production in china were introduced.

关键词： materials life cycle assessment LCIA methodology

Fe-Cr-Y_2O_3 MICRO-CRYSTALLINE COATINGS DEPOSITED BY SERIES ELECTRO-PULSE DISCHARGE

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Acta Metallurgica Sinica(English Letters) 2002年第4期15卷 331-338页

作者： Q. Xu,Y.D. He,D.R. Wang,H.B. Qi,Z.W. Li and W.Gao beijing Key Laboratory for Corrosion, Erosion and Surface technology, university of science and technology beijing, beijing 100083, china Department of chemical and material engineering, The university of beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing

A new technique-series electro-pulse discharge (SEPD)-was developed as a sur-face coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Fe-Cr and Fe-Cr-Y2O3 micro-crystalline coatings were deposited on stain-less steel (Fe-18Cr-8Ni) surfaces. Oxidation at 950℃ in ambient air showed that the coatings greatly improved the oxidation resistance of the steel. The addition of dis-persed Y2O3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the adhesion of oxide scales.

关键词： series electro-pulse discharge Fe-Cr-Y2O3 micro-crystalline al-loy coating high-temperature oxidation

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. Institute 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.

Study on BaTiO_3 films prepared by AC power microarc oxidation

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science china(Technological sciences) 2009年第8期52卷 2195-2199页

作者： HUANG WenBo, LI WenFang & HAN Bing college of material science and engineering, South china university of technology, Guangzhou 510640, china 1. college of material science and engineering South China University of Technology Guangzhou 510640 China

BaTiO3 films were prepared by microarc oxidation (MAO) with an in-house built alternating current (AC) power supply in Ba(OH)2 solution in this study. The surface morphology, combinability with the substrate and phase composition of the films were investigated by XRD, SEM and TEM. The BaTiO3 films were annealed at a temperature range of 900 to 1200℃ and phase compositions were tested thereafter. The results showed that the BaTiO3 films were mainly composed of the primitive hexagonal phase with relatively small amount of tetragonal and amorphous phases. Moreover, the amount of amorphous phase decreased with the time of annealing. The transformation of BaTiO3 from hexagonal structure to tetragonal stucture became obvious until the annealing temperature reached 1200℃. The film consisted mainly of BaTiO3 tetragonal structure with ferroelectric property. The influence of annealing on surface morphology and mechanism of phase transformation of the films were also discussed.

关键词： microarc oxidation ferroelectric film BaTiO3 annealing phase composition