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The Global Dynamics of a Class of Vector Fields in R3

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2469-2480页

作者： Xin An ZHANG zhao jun liang Lan Sun CHEN School of Mathematics and Statistics Central China Normal University Wuhan 430079 P. R. China Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

In this paper, .we find a bridge connecting a class of vector fields in R3 with the planar vector fields and give a criterion of the existence of closed orbits, heteroclinic orbits *** orbits of a class of vector fields in R3. All the possible nonwandering sets of this class of vector fields fall into three classes：（i） singularities; （ii） closed orbits; （iii） graphs of unions of singularities and the trajectories connecting them. The necessary and sufficient conditions for the boundedness of the vector fields are also obtained.

关键词： Tangent vector field invariant cone heteroclinic orbit vector field

Ice-templated preparation and sodium storage of ultrasmall SnO2 nanoparticles embedded in three- dimensional graphene

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Nano Research 2015年第1期8卷 184-192页

作者： Longkai Pei Qi Jin Zhiqiang Zhu Qing zhao Jing liang jun Chen Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Collaborative Innovation Center of Chemical Scienceand Engineering College of Chemistry Nankai University Tianjin 300071 China

We report on the ice-templated preparation and sodium storage of ultrasmall SnO2 nanoparticles （3--4 nm） embedded in three-dimensional （3D） graphene （SnO2@3DG）. SnO2@3DG was fabricated by hydrothermal assembly with ice-templated 3DG and a tin source. The structure and morphology analyses showed that 3DG has an interconnected porous architecture with a large pore volume of 0.578 cm^3·g^-1 and a high surface area of 470.5 m^2·g^-1. In comparison, SnO2@3DG exhibited a pore volume of 0.321 cmg.g^-1 and a surface area of 237.7 m^2·g^-1 with a homogeneous distribution of ultrasmall SnO2 nanoparticles in a 3DG network. SnO2@3DG showed a discharge capacity of 1,155 mA-h·g^-1 in the initial cycle, a reversible capacity of 432 mA·h·g^-1 after 200 cycles at 100 mA·g^-1 （with capacity retention of 85.7% relative to that in the second cycle）, and a discharge capacity of 210 mAh·g^-1 at a high rate of 800 mA·g^-1 This is due to the high distribution of SnO2 nanoparticles in the 3DG network and the enhanced facilitation of electron/ion transport in the electrode.

关键词： graphene three-dimensional ice-template metal oxide sodium-ion battery

A New Economical Sigma-Free Duplex Stainless Steel 19Cr-6Mn-1.0Mo-0.5Ni-0.5W-0.5Cu-0.2N

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Journal of Iron and Steel Research International 2011年第4期18卷 52-57页

作者： CHEN Hong DING Tie-suo LI jun XIAO Xue-shan zhao jun-liang JIANG Lai-zhu Institute of Materials Shanghai University Shanghai 200072 China Baoshan Iron and Steel Co Ltd Shanghai 200431 China

A new resource-saving duplex stainless steel with composition of 19Cr-6Mn-1.0Mo-0.5Ni-0.5W-0.5Cu-0.2N has been developed,and the microstructure,mechanical properties and corrosion properties have been *** results show that the alloy has a balanced ferrite-austenite relation,and the ferrite content rises with the solution treatment *** designed alloy is free of precipitation of sigma phase when aged at 650,750 and 850 ℃ for 3 h,respectively,whereas a few Cr23C6 precipitates are found after being aged at 750 ℃ for 8 *** impact tests indicate that the impact energy of the alloy is 68,200 and 220 J at-40,0 and 25 ℃,*** designed alloy solution treated at 1050 ℃ for 30 min has a much higher yield strength and similar corrosion resistance compared with those of AISI 304 austenitic stainless ***,the production cost of the alloy is about $ 1000 per ton which is lower than that of AISI 304.

关键词： duplex stainless steel sigma phase mechanical property pitting corrosion

Star Formation and Chemical Enrichment for Globular Clusters

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Chinese Physics Letters 2001年第11期18卷 1536-1538页

作者： LIN Qhig SHU Cheng-Gang CHANG Rui-Xiang zhao jun-liang Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030

A model considering gas outflows due to supernova explosions is developed for the star formation and chemical enrichment for the globular clusters (GCs) in the Milky Way galaxy. Through Monte Carlo simulations, the observed global properties of GCs can be well reproduced, including the metallicity distribution, no-correlation between cluster masses and galactocentric distances, etc. The predicted mass function of the parent clouds for the observed GCs at present day can be well described as a power law with the index of-1.8, which is consistent with the current observations for the molecular clouds.

关键词： galaxy observed clouds

Plant Regeneration from In Vitro Cultured Hypocotyl Explants of Euonymus japonicus Cu zhi

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Agricultural Sciences in China 2006年第3期5卷 196-201页

作者： SHANG Ai-qin CAI han YAN Xiao-jie HU Hai-zi zhao liang-jun Department of Ornamental Horticulture and Landscape Architecture China Agricultural University Beijing 100094 P.R.China College of Horticulture Hebei Agricultural University Baoding 071001 P.R.China Department of Horticulture College of Agriculture Yangzhou University Yangzhou 225009 P.R.China

Adventitious shoots were successfully regenerated from hypocotyl explants of in vitro cultures of Euonymus japonicus Cu zhi. Hypocotyl slices were cultured on Murashige and Skoog （MS） and B5 basal medium supplemented with varied concentration of different plant growth-regulators, e.g., α-naphthaleneacetic acid （NAA） and indole-3-butyric acid （IBA） in combination with 6-benzylaminopurine （6-BA） and kinetin. The study showed that shoots could be directly regenerated from hypocotyl explants without the intervening callus phase; MS medium was more suitable for adventitious shoots regeneration. The ability of hypocotyls segments to produce shoots varied depending upon their position on the seedlings. The highest regeneration rate was obtained with hypocotyl segments near to the cotyledon cultured on MS basal medium supplemented with 1.5 mg L^-1 6-BA and 0.05 mg L^-1 NAA （63.64%）. The regenerated shoots were readily elongated on the same medium as used for multiplication and rooted on half-strength MS basal medium supplemented with 1.0 mg L^-1 IBA and 100 mg L^-1 activated carbon. After being transferred to greenhouse conditions, 96% of the plantlets were successfully acclimatized. This regeneration system is applied for genetic transformation now.

关键词： Euonymus japonicus Cu zhi hypocotyl explants adventitious shoots plant regeneration

SYNTHESIS，CHARCTERIZATION　AND　CATALYTIC　RESEARCH　OF　THE　NEW　TYPE　LAYERED　MICROPOROUS　MATERIAL－ZnAl　ANION　CLAY　PILLARBD　BY　GaW_9Fe_3

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Chinese Chemical Letters 1995年第12期6卷 1083-1084页

作者： Ji Yu ZHANG Xin Wu YU Shu Yun ZHANG Chang Wen HU zhao jun liang En Bo WANG (Department of Chemistry, Northeast Normal University, Changchun 130024) NE Normal Univ Dept Chem Changchun 130024 Peoples R China

In this paper. tungstogallic heteropolyaniou trisubstituted with transition metal ferrum GaW9Fe3 was intercalated into ZnAl-NO3 type anion clay by means of ion-exchange for the first time. XRD patterns show that the pillated derivative possesses a gallery height of 0.98nm. IR spectra exhibit that the Keggin structure of intercalated heteropolyanion is remained. The new material was found to be catalytically efficient for the esterification of phthalic anhydride with 2-ethyl hexanol.

关键词： Fe BY PILLARBD CLAY LAYERED TYPE ANION AND