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Influence of Alloying Elements on Mechanical Properties and Corrosion Resistance of Cold Rolled C-Mn-Si TRIP Steels

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Journal of Iron and Steel Research International 2012年第12期19卷 42-47页

作者： zhang ling-yun WU Di LI Zhuang Liaoning Key Laboratory of Aircraft Digital Manufacturing and Test Technologies Shenyang Aerospace University Shenyang 110136 Liaoning China State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China School of Materials Science and Engineering Shenyang Aerospace University Shenyang 110136 Liaoning China

The rust layer plays an important role in the corrosion of steel in chlorinated environments. Salt spray, po- tentiodynamic polarization curve and tensile test were conducted in laboratory for the specimens after two-stage heat treatment. The influence of the alloying elements on mechanical properties and corrosion resistance of three kinds of steels was investigated by observing the microstructure and the morphologies of rust layer. The results show that the highest value （29%） of total elongation for steel A is obtained. The mechanical property of the specimen for steel C exhibits best strength ductility balance （21 384 MPa ·%） because of the presence of the multiphase microstructures after a two-stage heat treatment and the addition of the alloying elements. The corrosion products are known to be a complex mixture of Fe3O4 , Fe2O3 and α-FeOOH for steel C. The presence of the alloying elements results in the for mation of compact and dense rust layers in steel B and C. Passive film protects the substrate of TRIP （transformation induced plasticity） steel containing a complex mix of multiphase. Superior corrosion performance is exhibited for steel C with low alloying contents due to the enrichment of alloying elements within the rust layers.

关键词： TRIP steel alloying element rust layer mechanical property corrosion performance

Electron-Electron Interaction Effect on the Conformational Soliton of Deoxyribonucleic Acid

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Chinese Physics Letters 1999年第8期16卷 613-615页

作者： zhang ling-yun SUN Hong LIN Jia-ti Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080 Department of Modern Applied Physics Center of Atomic and Molecular SciencesTsinghua UniversityBeijing 100084 Department of Applied Physics Tianjin UniversityTianjin 300072

The local conformational behavior of deoxyribonucleic acid(DNA)has been discussed by considering the electron-electron *** set up the coupled nonlinear equations to describe the interaction between the longitudinal displacement of DNA backbone and the electronic wave *** the case of approximated condition,we obtain the analytic solution of the electronic wave function and longitudinal *** influence of electron-electron interaction upon the parameters of conformational soliton such as the amplitude and width have been *** the increasing of electron-electron interaction,the amplitude and half-width will increase.

关键词： interaction. function. Electron

Temperature Effect on Giant Magnetoresistance in Magnetic Multilayers

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Chinese Physics Letters 1996年第1期13卷 50-53页

作者： zhang ling-yun YANG Guo-lin LI Bo-zang PU Fu-ke Institute of Physics AcademiaSinicaBeijing 100080

We have presented the electronic free energy with respect to the magnetization and the model of the electronic density of *** expression of the giant magnetore-sist^nce has been obtained by considering the spin splitting of the electronic energy *** approach explained the temperature effect on the giant magnetoresistancG in magnetic multilayers.

关键词： resistance electronic magnetization

A New Tin Graphite Intercalation Compound for Lithium Ion Batteries

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Chemical Research in Chinese Universities 2006年第5期22卷 639-642页

作者： XIE Hai-ming YAN Xue-dong YU Hai-ying zhang ling-yun YANG Gui-ling XU Yang WANG Rong-shun Department of Chemistry Northeast Normal University Changchun 130024 P. R. China Department of Chemistry Inner Mongolia University for NationalitiesTongliao 028043 P. R. China

A new composite material was fabricated by intercalating tin nanoparticles into graphite. The tin graphite intercalation compound（Sn-GIC） was prepared by the interactions of tin tetrachloride with KC8 （K-GIC） in tetrahydrofuran （THF）. As the anode of lithium ion batteries, Sn-GIC presents a steady reversible capacity（363 mA·h/g） and a good cycling performance in comparison with Sn and SnO2, it suggests that the association of tin with graphite not only improves the reversible capacities, but also prevents the volume changes resulted from lithium insertion and extraction with tin during a charge-discharge process.

关键词： Lithium ion battery Anode material Sn-GIC

Conserving Agricultural Heritage Systems through Tourism: Exploration of Two Mountainous Communities in China

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Journal of Mountain Science 2013年第6期10卷 962-975页

作者： SUN Ye-hong Mary Jane DELA CRUZ MIN Qing-wen LIU Mou-cheng zhang ling-yun Institute of Tourism Beijing Union University Land and Water Division Natural Resources and Environment Management Department Food and Agriculture Organization Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences

Community plays an important role in the preservation of agricultural heritage system （AHS）. Recently, many AHS have been valorized as interesting resources for rural tourism. The expectations are that tourism development （TD） can be supportive for the conservation of AHS while creating benefits for local communities. In this study, two mountainous pilot villages （Longxian and Xiaohuang） in a global conservation project for traditional agricutural systems - Globally Important Agricultural Heritage Systems （GIAHS） were selected to identify the relationship between AHS conservation and TD. The study undertook in-depth interviews, and questionnaires of village residents and informal discussions with local villagers. A t-test and a linear regression model were implemented to explore the comparative dimensions of the two communities with different geographical location, economic situation, and stage of TD. The research found some similarities and differences in the two mountainous communities during AHS conservation and TD. Firstly, AHS are preservaed well in both villages unconsiously, while the residents in Xiaohuang value more highly the heritage elements than the respondents in Longxian, and the villagers in Xiaohuang are more worried about their heritage system; Secondly, both villages expect lots of benefits from TD and they clearly perceive more positive than negative impact from tourism and thus approve TD, while the hugedifferent perception on transportation and accessibility in the two villages reflects the bottleneck of TD in Xiaohuang village. At the same time, the respondents from Xiaohuang perceive more positive and fewer negative impact from tourism than the respondents from Longxian. Thirdly, the respondents in the two villages all show positive attitudes towards participation in tourism mostly motivated by the high income expectation. The main factors to determine the community perception in two villages were also analyzed based on the data process. A lo

关键词： Agricultural heritage system Tourismdevelopment Mountainous communities ZhejiangProvince Guizhou Province China

Stannous oxalate as a novel catalyst for the synthesis of polytrimethylene terephthalate

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Chinese Chemical Letters 2007年第7期18卷 872-874页

作者： Yu Rong Ren Shu Yong Jia Shou Cai zhang Chun ling Liu yun Cheng Cui Department of Chemistry Jilin Normal University Siping 136000 China

Stannous oxalate was prepared efficiently and characterized by XRD and FT-IR. It exhibited higher catalytic activity and had profitable effect than tetrabutyl titanate and stannous octoate for the synthesis of polytrimethylene terephthalate （PTT） via esterification-route. Over this catalyst, the degree of esterification of pure terephthalic acid was up to 94.4% at 260 ℃ after 1.5 h,while the intrinsic viscosity and content of terminal carboxyl groups of the corresponding PTT polyester, polymerized at 260 ℃,60 Pa for 2 h, was 0.8950 dL/g and 15 mol/t, respectively. Stannous oxalate was a promising catalyst for the synthesis of PTT polyester.

关键词： Polytrimethylene terephthalate Polyester Stannous oxalate Esterification-route Intrinsic viscosity

Effect of Cisplatin on the Flexibility of Linear DNA

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Chinese Physics Letters 2011年第6期28卷 344-347页

作者： JI Chao zhang ling-yun HOU Xi-Miao DOU Shuo-Xing WANG Peng-Ye Key Laboratory of Soft Matter Physics Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190

With the aid of an atomic force microscope(AFM),we study the interaction between linear DNA fragment and *** different cisplatin concentrations,the AFM used to observe the conformation of DNA has a gradual *** contour length,the end-to-end distance and the local bend angles of the linear DNA fragment can be accurately *** persistence length of DNA interacting with cisplatin is decreased with the increasing cisplatin ***,it is demonstrated that the local bend angles of DNA chains are increased by the binding interaction of cisplatin.

关键词： cisplatin concentration Cisplatin

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致密碎屑岩储层评价方法研究

石油地球物理勘探 2008年第5期43卷 595-599,487-488页

作者：张凌云中国石化石油工程西南公司测井分公司四川成都610100

百色盆地东部拗陷中央凹陷带那读组为陆相碎屑岩沉积地层,储集层的特点是岩性致密,孔隙结构复杂,非均质性较强,横向可对比性较差,用传统解释方法对其储层进行正确评价比较困难。综合岩心分析、储层电性特征对该区储层进行系统研究,初步... 详细信息

百色盆地东部拗陷中央凹陷带那读组为陆相碎屑岩沉积地层,储集层的特点是岩性致密,孔隙结构复杂,非均质性较强,横向可对比性较差,用传统解释方法对其储层进行正确评价比较困难。综合岩心分析、储层电性特征对该区储层进行系统研究,初步形成了一套用常规测井资料综合评价致密碎屑岩储层评价技术,包括流体性质判别、孔隙结构评价、储层非均质性评价、储层分类、产量预测等方法,并通过实例进行了效果评价,证实该技术的应用可有效地促进中央凹陷带的勘探开发。

关键词：测井评价那读组碎屑岩致密非均质孔隙结构百色盆地

支持向量机在富氮含能离子盐撞击感度定量构效关系研究中的应用

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含能材料 2023年第5期31卷 448-456页

作者：张云苓白杨北京农业职业学院国际教育学院北京100012 北京理工大学化学与化工学院原子分子簇科学教育部重点实验室北京100081

为了研究富氮含能离子盐的撞击感度(IS)与分子结构的关系,在M06-2X/6-311++G(3df,3pd)理论水平下对21种含能离子盐进行了构型优化和量子化学参数计算,并以IS为目标值,以最高占据轨道能量(E_(HOMO))、最低空轨道能量(E_(LUMO))、偶极矩(... 详细信息

为了研究富氮含能离子盐的撞击感度(IS)与分子结构的关系,在M06-2X/6-311++G(3df,3pd)理论水平下对21种含能离子盐进行了构型优化和量子化学参数计算,并以IS为目标值,以最高占据轨道能量(E_(HOMO))、最低空轨道能量(E_(LUMO))、偶极矩(μ)、极化率(α)、氧平衡(OB)、核独立化学位移(NICS)、可利用自由体积(ΔV)、静电势方差(σ^(2))、电离势(I)和电子亲和势(A)作为描述符,采用主成分分析(PCA)方法结合支持向量机(SVM)回归算法,建立了相关性较好的构效关系(QSPR)模型(相关系数和均方根误差分别为0.98和0.11)。采用该模型对新设计的6种新型富氮含能离子盐的IS进行预测,发现其中基于氮(-5(-1氢-四唑-5-基)-2氢-1,2,3-三唑-4-基)-4-硝基-呋咱-3-胺(HTANFT)设计的三种含能离子盐的撞击感度(依次为18,17,35 J)比传统炸药TNT(15 J)还要钝感,表明基于HTANFT设计的三种含能离子盐是潜在的理想含能材料。

关键词：富氮含能离子盐撞击感度(IS) 定量构效关系(QSPR) 支持向量机(SVM) 主成分分析(PCA)