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Creation of Air-Cooled Mn Series Bainitic Steels

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Journal of Iron and Steel Research International 2008年第6期15卷 1-9页

作者： FANG Hong-sheng FENG chun zheng Yan-kang yang Zhi-gang BAI Bing-zhe Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

The development and mechanical performances of new type air-cooled Mn series bainitic steels including granular bainitic steels, FGBA/BG duplex steels, CFB/M duplex steels, medium carbon bainite/martensite steels, cast bainitic steels invented by the authors are summarized. The novel series of bainitic steels are alloyed with Mn, and several series bainitic duplex microstructures can be easily obtained under the condition of air cooling through unique composition design. The invented idea, the principle of alloying design, the strengthening mechanism, and the evolution of the microstructure of new type air cooled Mn series bainitic steels are presented. Furthermore, the applications in different fields of these Mn series air cooled bainitic steels with different strength level are also introduced. It is suggested that the significance of the development of the air cooled Mn series bainitic steel can be summarized as follows： reducing costs of both raw materials and production; good combination of strength and toughness; self-hardening with high bainitic hardenahility by air cooling from hot working without additional quenching-tempering treatment or quenching procedure; large savings in energy resources; and reduced environmental pollution.

关键词： bainite bainitic steel microstructure mechanical property air cooling

Bursting behaviours in cascaded stimulated Brillouin scattering

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Chinese Physics B 2012年第1期21卷 310-313页

作者： Liu Zhan-Jun He Xian-Tu zheng chun-yang Wang Yu-Gang Institute of Applied Physics and Computational Mathematics Beijing 100094China State Key Laboratory of Nuclear Physics and Technology Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China

Stimulated Brillouin scattering is studied by numerically solving the Vlasov Maxwell system. A cascade of stim- ulated Brillouin scattering can occur when a linearly polarized laser pulse propagates in a plasma. It is found that a stimulated Brillouin scattering cascade can reduce the scattering and increase the transmission of light, as well as intro- duce a bursting behaviour in the evolution of the laser-plasma interaction. The bursting time in the reflectivity is found to be less than half the ion acoustic period. The ion temperature can affect the stimulated Brillouin scattering cascade, which can repeat several times at low ion temperatures and can be completely eliminated at high ion temperatures. For stimulated Brillouin scattering saturation, higher-harmonic generation and wave wave interaction of the excited ion acoustic waves can restrict the amplitude of the latter. In addition, stimulated Brillouin scattering cascade can restrict. the amplitude of the scattered light.

关键词： bursting behaviour stimulated Brillouin scattering cascade

Technology Development for Controlling Slab Transverse Corner Crack of Typical Micro-alloyed Steels

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Journal of Iron and Steel Research International 2015年第2期22卷 99-105页

作者： Hui ZHANG chun-zheng yang Ming-lin WANG Hong-biao TAO He-ping LIU Xue-bing WANG Central Iron and Steel Research Institute Shougang Jingtang United Iron and Steel Co. Ltd.

A mathematical model for simulating the fluid flow, heat transfer and solidification in the conventional mold and the chamfer mold, together with a finite element stress-strain model in the straightening process of both molds, were established for the typical niobium, vanadium, and titanium micro-alloyed steels. On the basis of both numerical analysis, the mold copper plate with an optimum chamfered shape was designed and applied in industrial tests. The predicted results from numerical simulation of fluid flow, heat transfer and solidification in the conven tional mold and the chamfer mold show that the increased chamfered angle leads to an approximately linear increase o[ the slab surface temperature, but it also causes strong flow near the slab corner. Very small chamfered length can lead to a significant increase of the temperature near the slab corner. However, with further increasing the chamfered length, the temperature of the slab corner increased slightly. The calculated results from the finite element analysis of stress-strain during the straightening process show that at the same slope width, the tangential strain on the slat） edges and corners is minimum when the chamfered angle is 30° and 45°, which is only 40° to 46° of rectangular slabs with the same cross-section area. At the same chamfered angle of 30°, when the chamfered length is controlled between 65-85 mm, the tangential strain on the part of the slab edges and corners is relatively smaller. Industrial test results show that the slab corner temperature at straightening segment increases about 100 ℃ by using chamfer mold compared to the conventional molds. The slab transverse corner cracks have been reduced more than 95° in comparison with those in the conventional mold.

关键词： micro-alloyed steel transverse corner crack chamfer mold slab

High uniformity and forming-free ZnO-based transparent RRAM with HfO_x inserting layer

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Chinese Physics B 2018年第8期27卷 549-553页

作者： Shi-Jian Wu Fang Wang Zhi-Chao Zhang Yi Li Ye-Mei Han zheng-chun yang Jin-Shi Zhao Kai-Liang Zhang School of Electronics Information Engineering Tianjin Key Laboratory of Film Electronic ＆ Communication DevicesTianjin University of TechnologyTianjin 300384China

The impacts of HfOx inserting layer thickness on the electrical properties of the ZnO-based transparent resistance random access memory （TRRAM） device were investigated in this paper. The bipolar resistive switching behavior of a single ZnO film and bilayer HfOx/ZnO films as active layers for TRRAM devices was demonstrated. It was revealed that the bilayer TRRAM device with a 10-nm HfOx inserted layer had a more stable resistive switching behavior than other devices including the single layer device, as well as being forming free, and the transmittance was more than 80% in the visible region. For the HfOx/ZnO devices, the current conduction behavior was dominated by the space-charge-limited current mechanism in the low resistive state （LRS） and Schottky emission in the high resistive state （HRS）, while the mechanism for single layer devices was controlled by ohmic conduction in the LRS and Poole-Frenkel emission in the HRS.

关键词： transparent resistive random access memory (TRRAM) HfOx inserting layer uniformity forming-free

Genetic Analysis and Gene Mapping of a Rice Tiller Angle Mutant tac2

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Rice science 2009年第4期16卷 323-326页

作者： FANG Li-kui SANG Xian-chun yang zheng-lin LIN Ying-hua WAN Nan HE Guang-hua Rice Research Institute~Key Laboratory of Biotechnology and Crop Quality Improvement Ministry of Agriculture Southwest University Chongqing 400716 China

Tiller angle, a very essential agronomic trait, is significant in rice breeding, especially in plant type breeding. A tiller anglo controlling 2 （tac2） mutant was obtained from a restorer line Jinhui 10 by ethyl methane sulphonate mutagenesis. The tac2 mutant displayed normal phenotype at the seedling stage and the tiller angle significantly increased at the tillering stage, A preliminary physiological research indicated that the mutant was sensitive to GA. Thus, it is speculated that TAC2 and TAC1 might control the tiller angle in the same way. Genetic analysis showed that the mutant trait was controlled by a major recessive gene and was located on chromosome 9 using SSR markers. The genetic distances between TAC2 and its nearest markers RM3320 and RM201 were 19.2 cM and 16,7 cM, respectively.

关键词： rice tiller angle mutant gene mapping genetics

超强短脉冲激光在不同密度分布等离子体中的自聚焦

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物理学报 2006年第1期55卷 310-320页

作者：王伟民郑春阳中国工程物理研究院研究生部北京2101信箱100088 北京应用物理与计算数学研究所北京8009信箱100088

讨论高斯型强激光束在具有初始柱对称密度分布的低密度冷等离子体中传播时,等离子体密度分布的不同对激光自聚焦的影响.推导出可以判断更有利于自聚焦发生的评价函数,这样通过比较不同密度分布的评价函数值就可以判断哪种密度分布更有... 详细信息

讨论高斯型强激光束在具有初始柱对称密度分布的低密度冷等离子体中传播时,等离子体密度分布的不同对激光自聚焦的影响.推导出可以判断更有利于自聚焦发生的评价函数,这样通过比较不同密度分布的评价函数值就可以判断哪种密度分布更有利于自聚焦的发生.为了说明这种方法的有效性,对评价函数进行分析得出:在相同的激光场中等离子体柱的轴心密度给定时(以激光的光轴为轴),离轴越远的地方密度越大及密度变化越陡,自聚焦越容易发生;相对论效应与有质动力共同作用比相对论的单独作用,自聚焦更容易发生.数值模拟证实了评价函数能准确的预测在不同的等离子体密度分布中哪种密度分布使激光的自聚焦更容易发生.

关键词：自聚焦相对论效应有质动力评价函数

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激光等离子体受激散射的线性理论研究

物理学报 2010年第12期59卷 8717-8724页

作者：项江郑春阳刘占军北京应用物理与计算数学研究所北京100094 北京大学应用物理与技术中心北京100871

利用包含两种阻尼(Landau阻尼和碰撞阻尼)成分的受激拉曼散射(SRS)、受激布里渊散射线性分析程序LIP,在给定的等离子体状态下分析了阻尼成分、激光强度以及等离子体组分对点火尺度等离子体中受激散射不稳定性发展的影响.详细评估了碰撞... 详细信息

利用包含两种阻尼(Landau阻尼和碰撞阻尼)成分的受激拉曼散射(SRS)、受激布里渊散射线性分析程序LIP,在给定的等离子体状态下分析了阻尼成分、激光强度以及等离子体组分对点火尺度等离子体中受激散射不稳定性发展的影响.详细评估了碰撞阻尼的效应,发现碰撞阻尼在接近1/4临界密度处能有效抑制受激散射的增长,从而造成SRS光谱上的"缝"现象.同时,电子温度的升高会在特定的密度区域促进SRS的发展.研究结果可为点火实验的设计提供参考.

关键词：激光受激散射线性稳定性分析阻尼增益指数

高强度激光与等离子体相互作用中的受激Raman级联散射、光子凝聚以及大振幅电磁孤立子的产生与加速

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物理学报 2006年第10期55卷 5325-5337页

作者：李百文郑春阳宋敏刘占军北京应用物理与计算数学研究所北京100088 中国农业大学理学院物理系北京100083

应用一维相对论电磁粒子模拟程序,详细研究了线性极化强激光入射到无碰撞稀疏密度长等离子体中引起的受激Raman散射、Raman级联散射、级联散射到光子凝聚、以及大振幅电磁孤立子的产生与加速.通过研究发现:在适当的激光振幅和等离子体... 详细信息

应用一维相对论电磁粒子模拟程序,详细研究了线性极化强激光入射到无碰撞稀疏密度长等离子体中引起的受激Raman散射、Raman级联散射、级联散射到光子凝聚、以及大振幅电磁孤立子的产生与加速.通过研究发现:在适当的激光振幅和等离子体状态下,强的光子凝聚现象会导致大振幅电磁孤立子的产生,电磁孤立子可以以静止、向后以及向前加速的形式存在;在密度均匀的等离子体中,电磁孤立子的加速不仅依赖于激光振幅而且依赖于等离子体的长度;电磁孤立子的电磁频率大约为未扰动电子等离子体振荡频率的二分之一左右,孤立子内电磁场的电场具有半周期结构,相应电磁场的磁场以及静电场则具有一个完整的周期结构.

关键词：粒子模拟受激Raman散射 Raman级联散射光子凝聚电磁孤立子

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两种芳香β-二酮化合物的合成及表征

化学研究与应用 2006年第12期18卷 1436-1439页

作者：郑春阳郑静范玲汪敦佳华中师范大学化学学院湖北武汉430079 生化分析技术湖北省重点实验室湖北师范学院化学与环境工程系湖北黄石435002

Two new aromatic β-diketones,1-phenyl-3-（6methoxy-1-naphthyl）propane-1,3-dione（a） and 1-（4-tert-butylphenyl）-3-（6-methoxy-1-naphthyl）propane-1,3-dione（b） were synthesized from aromatic ketone and ester by classical Claisen condensation using NaNH2 as strong *** their structures were determined by means of UV,IR,1H NMR spectra and elemental *** results show that two β-diketone compounds have strong ultraviolet absorption and exist in the enol form in chloroform solvent.

关键词： β-二酮化合物合成 Claisen缩合