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Gene flow from transgenic oilseed rape (Brassica napus L.) to cruciferous weeds under mentor pollen inducement

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Progress in Natural Science:Materials International 2007年第11期17卷 1284-1289页

作者： Zhao Xiangxiang1,2, Luo Yuming1, Lu Weiping2, Qi Cunkou3. Pu Huiming3.and Wang Youping2(1. Biotechnology Key Laboratory of Eco-agriculture in Hongze Lake Region, Jiangsu Province, Huaiyin Normal college, Huai'an 223.01, china 2. Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou 225009, china 3. Institute of Industrial Crops, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, china) Biotechnology Key Laboratory of Eco-agriculture in Hongze Lake Region Jiangsu Province Huaiyin Normal College Huai'an 223001 China Jiangsu Provincial Key Laboratory of Crop Genetics and Physiology Yangzhou University Yangzhou 225009 China Institute of Industrial Crops Jiangsu Academy of Agricultural Sciences Nanjing 210014 China

The alien gene flow between genetically modified glyphosate-resistant rapeseed variety Q3.(Brassica napus L.) and four cruciferous weeds was studied under mentor pollen inducement. The results showed that when Thlaspi arvense L., Capsella bursa-pastoris (L.) Medic, Cardamine hirsuta L. and Rorippa palustris (L.) Besser were pollinated with mentor pollen, the mixed Q3.and the weed, pollen grains aggregated largely and germinated quickly, and the numbers of pollen tubes penetrating into the style and the ovary were greatly increased as compared with corresponding self-pollination groups. Twenty four to forty eight hours after pollination, several pollen tubes were observed to penetrate into the ovule via micropyle in each mentor combination. However, when the mentor progenies were analyzed by PCR, all of them showed negative for the Q3.herbicide-resistant gene. Collectively, these results indicated that crossing between T. arvense, C. bursa-pastoris, C. hirsuta, R. palustris (as female) and Q3.(as male) was highly incompatible and the herbicide-resistant gene could not flow from Q3.to these four weeds.

关键词： herbicide-resistant rapeseed cruciferous weeds mentor pollination aniline blue fluorescence gene flow

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science china Earth Sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2, AN Lizhe1, 3. WU Guangjian2, XU Baiqing2, MA Xiaojun 3. LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000, china 2. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, china 3. college of Life Science, Lanzhou University, Lanzhou 73.000, china Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing china college of Life Science Lanzhou University Lanzhou china

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Finite Element Analysis of Die Geometry and Process Conditions Effects on Equal Channel Angular Extrusion for β-Titanium Alloy

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Journal of Iron and Steel Research International 2012年第10期19卷 54-58页

作者： SI Jia-yong1,2, GAO Fan3. ZHANG Ji3.(1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083. Hunan, china 2. college of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, Hunan, china 3. High Temperature Material Research Division, Central Iron and Steel Research Institute, Beijing 100081, china) [a] State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 Hunan China [b] college of Mechanical and Electrical Engineering Central South University of Forestry and Technology Changsha 410004 Hunan China [c] High Temperature Material Research Division Central Iron and Steel Research Institute Beijing 100081 China

The finite element analysis was applied to evaluate the respective influences of die geometry and process conditions on plastic strain distribution for β-titanium (Ti-13.11Cr3.l) alloy during the equal channel angular extrusion (ECAE). It was found that optimum equal channel angular extrusion die geometry is strongly material dependent. Optimal strain homogeneity in the Ti-13.11Cr3.l alloy may be achieved at r (inner radius)=5 mm, R (outer radius)=3.mm. The equivalent plastic strain increases with increasing friction coefficient. And the better homogeneity of the equivalent plastic strain distribution can be achieved when friction coefficient value is lower. The faster the ram speed is, the lower the homogeneity of the equivalent plastic strain distribution is and the influence is slight. The back-pressure does not help to improve the plastic strain homogeneity, and the increasing temperature has a slightly favourable effect on the plastic strain homogeneity between 400 and 600 ℃.

关键词： equal channel angular extrusion finite element analysis die geometry β-titanium

The Vibration Controllability of 20~# Steel Pipe Excited by Unsteady Flow

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Journal of Wuhan University of Technology(Materials Science) 2011年第6期26卷 1222-1226页

作者：寇子明 college of Mechanical Engineering Taiyuan University of Technology Shanxi Province Mine Fluid Control Engineering Research Center

An excited experiment system of 20# steel pipe was established with oil cylinder, 20# steel pipe, frequency converter, pump station and wave exciter generating unsteady flow artificially. The experimental results showed that the 20# steel pipe could vibrate with the excitation of unsteady flows, and the vibration was periodic, instead of a harmonic one. Particles on the front and rear positions of pipe vibrated synchronously, and the vibration intensity of the pipe＇s two ends was greater than in the middle. System pressure and wave exciter＇s frequency had much influence upon pipe＇s amplitude. Pipe＇s vibration frequency was little affected by system pressure, and its value was close to the wave exciter＇s. Therefore, the active control of pipe＇s vibration can be realized by setting system pressure and adjusting frequency converter＇s frequency.

关键词： unsteady flow steel pipe vibration control wave exciter

Enzymatic cyclization of linear peptide to plant cyclopeptide heterophyllin B

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Science china Chemistry 2006年第1期49卷 63-66页

作者： JIA Aiqun1, LI Xiang2, TAN Ninghua1, LIU Xiaozhu3. SHEN Yuemao1 & ZHOU Jun1 1. State Key Laboratory of Phytochemistry and Plant Resources in West china, Kunming Institute of Botany, Graduate Univer-sity of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming 650204, china 2. Chinese Peptide Co., Ltd, Hangzhou 3.0018, china 3. Southwest Forestry {3., Kunming 650204, china 1. State Key Laboratory of Phytochemistry and Plant Resources in West china Kunming Institute of Botany Graduate University of Chinese Academy of Sciences Chinese Academy of Sciences Kunming 650204 China 2. Chinese Peptide Co. Ltd Hangzhou 310018 China 3. Southwest Forestry college 650204 Kunming China

The crude enzyme (PH-1) isolated from Pseudostellaria heterophylla by ourgroup has catalyzed enzymatic cyclization of linear peptideNH_2-Gly^1-Gly^2-Leu-Pro-Pro-Pro-lle-Phe-COOH (4) into cyclopeptide heterophyllin B (HB) from plantfor the first time. To ensure this reaction, some analytical methods including TLC, HPLC, MS, NMR,and ^(13.C labeling were used to prove that the reaction of substrate 4 sharing residue ofNH-Phe-Gly-CO was successful.

关键词： Pseudostellaria heterophylla, cyclopeptides, HB, enzymatic cyclization, isotope labeled.

Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW china: Evi- dence from clinopyroxene exsolution in garnet

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Science china Earth Sciences 2005年第7期48卷 1000-1010页

作者： LIU Liang1,3. CHEN Danling1, ZHANG Anda1, SUN Yong1, WANG Yan1, YANG Jiaxi1,2 & LUO Jinhai1 1. Key Laboratory of Continental Dynamics of the Ministry of Education of china, Northwest University, Xi’an 710069, china 2. college of Earth Science and Land Resources, Chang’an University, Xi’an 710054, china 3. The Laboratory of Orogen and Basin of the Ministry of Education, Peking University, Beijing 100871, china Key Laboratory of Continental Dynamics Ministry of Education of China Northwest University Xi'an 710069 China Laboratory of Orogen and Basin Ministry of Education Peking University Beijing 100871 China college of Earth Science and Land Resources Chang'an University Xi'an 710054 China

The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW china. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1) before exsolution has a maximum Si content of 3.061 per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1000℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the continental lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the continental crust, and such deep- subduction probably reaches to >200 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western china.

关键词： Altyn Tagh gneissic K-feldspar (-bearing) garnet clinopyroxenite clinopyroxene exsolution in garnet ultra-high pressure metamorphism.

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2,3., LI Xiao-wei 2,3.. School of Information Engineering, Zhejiang Forestry college, Hangzhou 3.13.0, Zhejiang, china 2. Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080, china 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003., china School of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Preparation and Characterization of Nanocomposite MgFe_2O_4/SiO_2

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 354-358页

作者：徐莉 college of Science Nanjing Forestry University

Nanocomposites MgFe2O4/SiO2 were successfully synthesized by the sol-gel method in the presence of N, N-dimethylformamide （DMF）. The formation of pure MgFe2O4 was confirmed by powder X-ray diffraction （XRD） and electron diffraction. The structural evolution of MgFe2O4 nanocrystals was followed by powder X-ray diffraction and IR absorption spectroscopy. The formation of spinel structure of MgFe2O4 started at 800 ℃, and completed at 900 ℃, The transmission electron microscopy （TEM） measurements suggest that the particle sizes increase with the increasing annealing temperature, and the mean particle sizes of the spherical samples annealed at 800 ℃, 900 ℃ and 1 050 ℃ are ca. 3.nm, 8 nm and 11 nm, respectively. Magnetization measurements at room temperature and 78 K indicate supemaramagnetic nature of these MgFe2O4 nanocrvstals.

关键词： nanocomposite sol-gel magnesium ferrite magnetic property

Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological Sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2, ZHANG Taihua1, LI Weihuo3.& WEI Bingchen3.1. State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sci- ences, Beijing 100080, china 2. college of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 3.0074, china 3. National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, china 1. State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. college of Physics and Electronic Information Science Tianjin Normal University Tianjin 300074 China 3. National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.