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无 氧 条 件 下TiO2 薄 膜 界 面 光 催 化 反 应 的XPS 研 究  [PDF]
杨喜昆,胡显智,何 兵,楚国栋
分子催化 , 2009,
Abstract: 设 计 利 用 X 射 线 光 电 子 能 谱 仪 的 高 真 空 系 统 作 为 无 氧 条 件 下 光 催 化 反 应 和 分 析 的 场 所 , 研 究 真 空 无 氧 环 境 和 大 气 有 氧 环 境 中 紫 外 光 激 发 TiO2 薄 膜 表 面 的 光 催 化 反 应 , 并 对 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 进 行 初 步 探 索 . 结 果 表 明 , 在 大 气 有 氧 和 真 空 无 氧 条 件 下 TiO2 薄 膜 经 紫 外 光 照 后 , 表 面 的 化 学 组 成 和 化 学 状 态 均 发 生 了 变 化 ; 在 有 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 增 加 , 而 在 无 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 减 少 . TiO2 薄 膜 表 面 的 吸 附 氧 是 维 持 无 氧 条 件 下 光 催 化 反 应 的 重 要 原 因 , 增 加 薄 膜 表 面 吸 附 氧 的 含 量 能 提 高 TiO2 薄 膜 在 无 氧 环 境 中 的 催 化 活 性 . 此 外 , 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 光 催 化 反 应 过 程 中 , 亚 甲 基 蓝 分 子 只 是 脱 去 了 某 个 含 氮 的 基 团 , 生 成 了 中 间 产 物 , 而 并 没 有 完 全 降 解 .
氧离子束辅助激光制备具有织构的ybco薄膜  [PDF]
王忠柯(),黄新堂(,),王又清(),王秋良(),陈清明()
材料研究学报 , 2000,
Abstract: ?应用氧离子束辅助准分子脉冲激光沉积薄膜技术,先在nicr合金(hastelloyc--275)基底上在室温下淀积具有平面织构的钇稳锆(ysz)缓冲层薄膜,再在ysz/nicr基底上在750℃下制备具有平面织构和高临界电流密度的yba2cu3o7-x(ybco)薄膜.ysz和ybco薄膜都为$c$--轴取向和平面织构的,ysz(202)和ybco(103)的x射线扫描衍射峰的全宽半峰值分别为18o和11o.ybco薄膜的临界温度和临界电流密度分别为90k(r=0)和7.9×105a/cm2(77k,零磁场).
Deposition and characterization of YBCO/CeO2/YSZ/CeO2 multilayers on biaxially textured Ni substrates
Wang Shu-Fang,Zhao Song-Qing,Liu Zhen,Zhou Yue-Liang,Chen Zheng-Hao,Lue Hui-Bin,Jin Kui-Juan,Cheng Bo-Lin,Yang Guo-Zhen,
王淑芳
,赵嵩卿,刘震,周岳亮,陈正豪,吕惠宾,金奎娟,程波林,杨国桢

中国物理 B , 2006,
Abstract: CeO$_{2}$/YSZ/CeO$_{2}$ buffer layers were deposited on biaxially textured Ni substrates by pulsed laser deposition. The influence of the processing parameters on the texture development of the seed layer CeO$_{2}$ was investigated. Epitaxial films of YBCO were then grown \textit{in situ} on the CeO$_{2}$/YSZ (yttria-stabilized ZrO$_{2}$)/CeO$_{2}$-buffered Ni substrates. The resulting YBCO conductors exhibited self-field critical current density $J_{\rm c}$ of more than 1 MA/cm$^{2}$ at 77K and superconducting transition temperature $T_{\rm c}$ of about 91K.
MAGNETIC PROPERTIES OF A YBCO CRYSTAL PREPARED BY MELT-TEXTURED GROWTH METHOD
熔融织构YBCO的磁性

WEI CHONG-DE,LIU ZUN-XIAO,LAN JIAN,SUN YUN-XI,GAN ZI-ZHAO,REN HONG-TAO,XIAO LINO,HE QING,
卫崇德
,刘尊孝,兰健,孙允希,甘子钊,任洪涛,肖玲,贺庆

物理学报 , 1991,
Abstract: 测量了熔融织构YBCO样品从1.5K到89K的磁化曲线。磁场H平行于c轴时,在1.5K,7K和10K观察到磁通跳跃,在15—83K的温度区间观察到峰值现象。详细分析了磁化曲线和磁临界电流的各向异性。讨论了晶粒之间连接的性质和主要的钉扎中心。
Effect of mesoscopic inhomogeneities on the critical current of bulk melt-textured YBCO  [PDF]
L. S. Uspenskaya,I. G. Naumenko,G. A. Emelchenko,Yu. B. Boguslavskii,S. A. Zverkov,E. B. Yakimov,D. Litzkendorf,W. Gawalek,A. D. Caplin
Physics , 2003, DOI: 10.1016/S0921-4534(03)00629-4
Abstract: The downsizing 211-inclusions and an increase of their density leads to rise in mean critical current value in Y-based melt textured material. Very often 211-inclusion are spread in the material volume non-homogeneous, with typical scale 50 - 100 micrometer. Therefore it is difficult to find the real correlation between local critical current and the inclusions distribution. We performed a study of a local critical current using modified magneto-optic technique on a melt-textured YBaCuO ceramic, found the areas with constant current and studied the real structure of the material in the areas, inclusions distribution and their sizes, by scanning electron microscopy and X-ray microanalysis. The estimation of a pinning in these places, by taking into account the amount of inclusions and the length of their boundaries, and comparison with the value of local critical current reveals a strait correlation between the density of inclusions and the current but shows remarkable quantitative disagreement.
Effect of Substrate Temperature and Dislocation Density on the Epitaxial Growth of YBCO Thin Films on Textured Metal Tapes  [PDF]
XU Ya-Xin, XIONG Jie, XIA Yu-Dong, ZHANG Fei, XUE Yan, TAO Bo-Wan
无机材料学报 , 2013, DOI: 10.3724/sp.j.1077.2013.12385
Abstract: Epitaxial YBa2Cu3O7-δ (YBCO) thin films were grown on Y2O3/YSZ/CeO2 (YYC) buffered Ni-5at%W substrates by direct-current sputtering, and induced by substrate temperature. X-ray diffraction (XRD) results showed that the substrate temperature strongly influenced the epitaxial growth of YBCO films: the a-axis preferential grains grew at lower substrate temperature, and strictly c-axis epitaxial YBCO films were achieved at higher substrate temperature. The amount of a-axis YBCO component evaluated from the ratio of XRD χ-scan integrated intensity of the a-axis and c-axis for the YBCO (102) plane decreased as the substrate temperature increased. Since the development of the a-axis component can result in high angle grain boundaries, which can degrade the Ic passing through the a–b plane, the microstructure and the critical current density of YBCO thin films were improved as substrate temperature increasing. While the microstructure and the critical current density of YBCO thin films were deteriorated above 780 or the baseband oxidation and the interface reaction between the YBCO and the buffer layer. The dislocation density in the YBCO thin films was measured and calculated. The relationship between the dislocation density and critical current density (Jc) was systematically investigated, Jc was much more sensitive to the screw dislocation than to the edge dislocation, which was attributed to the spiral growth mechanism of YBCO thin films.
MnO2/ZSM-5上 臭 氧 协 同 催 化 去 除 甲 醛 的 性 能 研 究  [PDF]
杨俊鹏,史文晶,施建伟,上官文峰
分子催化 , 2009,
Abstract:
STUDY ON THE TECHNOLOGY AND PROPERTY FOR Y2BaCuO5 PARTICLE S ARTIFICIAL DOPING TO OBTAIN SINGLE-CRYSTAL DOMAIN MELT-TEXTURED YBCO BULK SUPE RCONDUCTOR
Y2BaCuO5粒子掺杂的单畴熔融织构YBCO超导体工艺与性能研究

SHA JIAN-JUN,YAO ZHONG-WEN,YU JIN-NAN,YU GANG,LUO JIN-HAN,WEN HAI-HU,YANG WAN-LI,LI SHI-LIANG,
沙建军
,姚仲文,郁金南,郁 刚,罗金汉,闻海虎,杨万里,李世亮

物理学报 , 2000,
Abstract: 采用人工掺杂Y-211相的方法以及熔融织构生长结合顶部籽晶工艺制备了不同211粒子含量的 准单畴熔融织构的YBCO块材料,样品致密度高,体密度大于62g/cm3,机械强 度好,振动样品磁强计测量结果表明,样品在温度30K、磁场06T下,其Jc仍 达到123×106A/cm2.在温度70K、磁场2T条件下,Jc 仍高达135×104A/cm2,而且临界电流密度对磁场不敏感.扫描电 子显微镜分析也表明,Y-211相的人工掺杂,能改善织构样品的生长状况,减小微裂纹,同 时,掺杂的Y-211粒子能作为强的钉扎中心,因此,这种工艺能精确地控制样品中Y-211粒子 的含量,所制备的样品中Y-211粒子分布越均匀,尺寸越小,其钉扎效果越好.从大量实验结 果比较得出,1∶05是最佳的掺杂比例.
Improvement of YBCO Film Properties by Twostep Deposition Using Spray Pyrolysis Method
LIU Min,SUO Hong-Li,ZHAO Yue,ZHANG Ying-Xiao,LIU Dan-Min,ZHOU Mei-Ling
无机材料学报 , 2007, DOI: 10.3724/sp.j.1077.2007.00377
Abstract: The YBCO films were directly deposited on the {110} <011> textured Ag substrates by an ultrasonic spray pyrolysis method using the modified device. The YBCO film made by one step deposition at 900 n textured Ag substrate has a weak in lane texture and low Jc value. The observed white points in this film consist of high content of Ag on the surface of this film, which are due to the vaporization and diffusion of Ag atoms at high deposition temperatures. While the performance of YBCO films can be significantly enhanced by using twostep deposition route, firstly predepositing the precursor film at 700 hen carrying out the second step depositing at 900 he results show that the two-step deposition can effectively prevent Ag atoms from vaporizing and diffusing into YBCO films and improve the surface roughness, texture and superconducting properties of YBCO films. The YBCO film being 15cm long, coated on {110}<011> textured Ag tape by this two-step deposition method exhibits a transport Jc value of more than 104A/cm2 at 77K.
A New Direct Process to Prepare YBa2Cu3O7-? films on Biaxially Textured Ag{110}<211>  [PDF]
Rongping Wang,Yueliang Zhou,Shaohua Pan,Meng He,Zhenghao Chen,Guozhen Yang
Physics , 1999, DOI: 10.1016/S0921-4534(99)00487-6
Abstract: YBCO films were successfully prepared on biaxially textured Ag{110}<211> substrates by using pulsed laser deposition. X-ray diffraction results showed that the degree of preferential orientation of Ag{110}<211> substrates varied with increasing annealing temperature. With a thin template layer deposited at low temperature, YBCO film with c-axis orientation and in-plane biaxial alignment could be obtained at high deposition temperature. Scanning electron microscopy observation revealed that YBCO grains enlarged but Ag grains on the surface of the YBCO films became smaller with increasing deposition temperature. At optimal deposition conditions, Ag atoms diffuse into the YBCO grain boundaries, and then fill in the weak-link regions in the YBCO film, resulting in the conduction easier. Jc value of 5?105A/cm2 was obtained at 77K and zero magnetic field for the best YBCO film in our work.
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