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chinese physics B 2017年第5期26卷 165-169页

作者：袁大伟李玉同朱保君李彦霏仲佳勇魏会冈刘畅原晓霞张喆梁贵云王菲鹿李芳赵家瑞华能朱宝强朱健强江少恩杜凯丁永坤赵刚张杰 Key laboratory of optical Astronomy National Astronomical Observatories Chinese Academy of Sciences National laboratory for condensed {2. physics Institute of Physics Chinese Academy of Sciences School of Physical sciences University of Chinese Academy of Sciences Collaborative Innovation center of IFSA(CICIFSA) Shanghai Jiaotong University Department of Astronomy Beijing Normal University National laboratory on High Power Lasers and physics Research center for Laser Fusion China Academy of Engineering Physics Key laboratory for Laser Plasmas(Ministry of Education)and Department of physics and Astronomy Shanghai Jiao Tong University

A counter-streaming flow system is a test-bed to investigate the astrophysical collisionless shock（CS） formation in the laboratory. Electrostatic/electromagnetic instabilities, competitively growing in the system and exciting the CS formation, are sensitive to the flows parameters. One of the most important parameters is the velocity, determining what kind of instability contributes to the shock formation. Here we successfully measure the evolution of the counter-streaming flows within one shot using a multi-pulses imaging diagnostic technique. With the technique, the average velocity of the high-density-part（ne ≥ 8–9 × 10^19cm^-3） of the flow is directly measured to be of ～ 10^6cm/s between 7 ns and 17 ***, the average velocity of the low-density-part（ne ≤ 2.× 10^19cm^-3） can be estimated as ～ 10^7cm/s. The experimental results show that a collisionless shock is formed during the low-density-part of the flow interacting with each other.

关键词： streaming counter interacting exciting instability determining diagnostic colors distinguish gamma

High Power VCSEL Device with Periodic Gain Active Region

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光机电信息 2007年第12期24卷 26-30,35页

作者： NING Yong-qiang1, QIN Li1, SUN Yan-fang1, LI Te1, CUI Jin-jiang1, PENG Biao1, LIU Guang-yu1, ZHANG Yan1, LIU Yun1, WANG Li-jun1, GUI Da-fu2. XU Zu-yan2.(1. Key laboratory of Excited State Processes, Changchun institute of Optics, Fine Mechanics and {2., chinese academy of sciences, Changchun, 130033, China 2. institute of {2., chinese academy of sciences, beijing, 100080, China) Key laboratory of Excited State Processes Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences Changchun 130033 China institute of physics Chinese Academy of Sciences Beijing 100080 China

High power vertical cavity surface emitting lasers(VCSEKLs) with large aperture have been fabricated through improving passivation, lateral oxidation and heat dissipation techniques. Different from conventional three quantum well structures, a periodic gain active region with nine quantum wells was incorporated into the VCSEL structure, with which high efficiency and high power operation were expected. The nine quantum wells were divided into three groups with each of them located at the antinodes of the cavity to enhance the coupling between the optical field and the gain region. Large aperture and bottom-emitting configuration were used to improve the beam quality and the heat dissipation. A maximum output power of 1.4 W was demonstrated at CW operation for a 400 μm-diameter device. The lasing wavelength shifted to 995.5 nm with a FWHM of 2.nm at a current of 4.8 A due to the internal heating and the absence of active water cooling. A ring-shape far field pattern was induced by the non-homogeneous lateral current distribution in large diameter device. The light intensity at the center of the ring increased with increasing current. A symmetric round light spot at the center and single transverse mode operation with a divergence angle of 16° were observed with current beyond 4.8 A.

关键词： VCSEL large aperture high power periodic gain Al2.3

Defects in La2.uO4 and La1.86Sr0.14CuO4 single crystals

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工程科学学报 2005年第2期 244-244页

作者： YANG Wei, JIA Liansuo, CHEN Xiaolong, and WANG Cong center of Materials physics and Chemistry, School of {2., Beihang University, beijing 100083, China institute of physics and center for condensed matter physics, chinese academy of sciences, beijing 100080, China

La2.uO4 and La1.86Sr0.14CuO4 single crystals were obtained by traveling solvent floating zone method. There were five kinds of defects in these single crystals: cracks, inclusions, gas bubbles, unhomogeneous distribution of Sr2., and substructures. CH3COOH aqueous solution was used to etch these single crystals, and the etch-pit density was calculated. The formation mechanism of these defects was discussed. It is suggested that the good preparation of raw materials and the stringent growth conditions play an important role in growing high quality single crystals.

关键词： defects TSFZ method etch-pit density

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人神经tau蛋白与DNA相互作用

生物化学与生物物理进展 2004年第10期31卷 918-923页

作者：曲梅花李辉徐艳娟赫荣乔中国科学院生物物理研究所中国科学院物理研究所

通过凝胶阻滞实验表明 ,人类神经tau能够与不同来源的DNA (λDNA ,质粒DNA以及PCR产物 )相结合 ,形成tau DNA复合物 .每分子神经tau大约与长度为 6～ 10bp的核苷酸片段结合 .原子力显微镜直接证实了tau与线性质粒DNA相结合形成串珠样的... 详细信息

通过凝胶阻滞实验表明 ,人类神经tau能够与不同来源的DNA (λDNA ,质粒DNA以及PCR产物 )相结合 ,形成tau DNA复合物 .每分子神经tau大约与长度为 6～ 10bp的核苷酸片段结合 .原子力显微镜直接证实了tau与线性质粒DNA相结合形成串珠样的结构 .采用单克隆抗体Tau 1,进行免疫组织化学的实验显示 ,神经tau不但弥散地分布在SY5Y细胞系的细胞质内 ,同时也存在于细胞核中 ,并形成染色致密的斑点 .以上结果提示 :神经tau在细胞核中可能参与了某种重要的生物学功能 .

关键词：人神经tau DNA 相互作用原子力显微镜(AFM)

SrTiO_3基片的晶体质量及表面粗糙结构的X射线研究

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物理学报 1997年第9期46卷 1758-1763页

作者：李超荣朱爱军戴道扬麦振洪中国科学院凝聚态物理中心中国科学院物理研究所中国科学院微重力实验室

用Ｘ射线双晶衍射摇摆曲线以及双晶Ｘ射线形貌对两个ＳｒＴｉＯ３基片的单晶质量进行了对比研究，并用Ｘ射线掠入射镜面反射及漫散射研究了它们的表面粗糙结构．结果表明，两个ＳｒＴｉＯ３基片中都存在镶嵌缺陷，其中一个样品的晶体质... 详细信息

用Ｘ射线双晶衍射摇摆曲线以及双晶Ｘ射线形貌对两个ＳｒＴｉＯ３基片的单晶质量进行了对比研究，并用Ｘ射线掠入射镜面反射及漫散射研究了它们的表面粗糙结构．结果表明，两个ＳｒＴｉＯ３基片中都存在镶嵌缺陷，其中一个样品的晶体质量相对较高．两个样品的表面粗糙结构相差很大，包括均方根粗糙度σ和横向相关长度ξ．σ分别为（０５±０１）和（１３±０１）ｎｍ，ξ分别为（１２００±２００）和（３００±２０）ｎｍ．样品的表面粗糙将增加Ｘ射线的漫散射强度而降低镜面反射的强度．晶体质量较高的样品，其表面也较平整，粗糙度较小。

关键词：钛酸锶基片晶体质量表面结构光电子材料

Synthesis and characterization of a three-ring bent-core compound

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Science Bulletin 2005年第17期 35-39页

作者： TANG Yanhong1, MEI Chongyu1, LI Shaojun2. WANG Yan1, WANG Xingdong1, WANG Lixiang1, YAN Donghang1 & YE Cheng2.1. State Key laboratory of Polymer physics and Chemistry, Changchun {2. of Applied Chemistry, chinese academy of sciences, Changchun 13002., China 2. center for Molecular Science, laboratory of Organic Solid, {2. of Chemistry, chinese academy of sciences, beijing 100080, China

To investigate the vacuum-deposited films of the banana-shaped mesogens, we prepared a three-ring bent-core (that is, banana-shaped) compound m-bis(4-p- octoxysryrenyl)benzene (m-OSB) and used it as a prototype for studying the related film physics. Herein the synthesis and the structural characterization of m-OSB are reported. 13C and 1H NMR spectra and IR spectrum confirm that m-OSB has a symmetric and all-trans conformation. The results of differential scanning calorimetry, polarizing optical microscopy and X-ray diffractometry indicate that no liquid crystalline phase but two crystalline phases are present in this material: phase I (T<66℃) and phase II (66℃更多还原AbstractFilter('ChDivSummary', 'ChDivSummaryMore', 'ChDivSummaryReset');

关键词： banana-shaped mesogens bent-core molecules anti-ferro-electric alignment.

CVD Synthesis of Single-Walled Boron Nitride Nanotubes

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CVD Synthesis of Single-Walled Boron Nitride Nanotubes

纳米晶永磁Pr_8Fe_(87)B_5反磁化机理研究

2.11中国材料研讨会

作者： Muhong Wu 1,3,Wenlong Wang,1,Xuedong Bai,1,Yu Sui 3,and Enge Wang,1,2.1 beijing National laboratory for {2. matter physics,institute of physics,chinese academy of sciences,beijing 100190,China 2.International center for Quantum Materials,School of physics,Peking University,beijing 100871,China 3 center for {2. matter Science and Technology (CCMSIT),Department of physics,Harbin institute of Technology,Harbin 150001,China

＜正＞As the binary III-VI homolog of carbon nanotubes（CNTs）,the boron nitride nanotubes（BNNTs）share the most structural similarity with CNTs and can be regarded as an important

关键词：

来源： cnki会议评论

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物理学报 2003年第3期52卷 722-725页

作者：张宏伟荣传兵张健张绍英沈保根中国科学院物理研究所与凝聚态物理中心磁学国家重点实验室北京100080

用熔体快淬法制备了Pr2.Fe1 4B α Fe纳米复合永磁样品 .测量了样品的起始磁化、反磁化过程、矫顽力和剩磁与外场的关系 ,以及样品的磁粘滞性 .经分析认为材料的矫顽力主要由非均匀的钉扎机理决定 ,但由于交换硬化的软磁相的可逆转动使... 详细信息

用熔体快淬法制备了Pr2.Fe1 4B α Fe纳米复合永磁样品 .测量了样品的起始磁化、反磁化过程、矫顽力和剩磁与外场的关系 ,以及样品的磁粘滞性 .经分析认为材料的矫顽力主要由非均匀的钉扎机理决定 ,但由于交换硬化的软磁相的可逆转动使得这种反磁化机理不同于单相永磁材料的钉扎行为 .磁粘滞性表明热激活主要源于硬磁相的不可逆磁化行为 .

关键词：纳米晶 Pr8Fe87B5 反磁化机理纳米复合永磁材料矫顽力剩磁磁粘滞

The Ge Critical Nuclei on Si(111)-(7×7)Surface at Room Temperature

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The Ge Critical Nuclei on Si(111)-(7×7)Surface at Room Temp...