直流磁控溅射一步法原位制备MgB2超导薄膜

用MgB2靶,控制直流磁控溅射工作在异常辉光放电或弧光放电状态,在SrTiO3衬底上原位一次性得到了MgB2超导薄膜,其起始转变温度为32K,零电阻温度为15K. 关键词： 高温超导体 超导薄膜 磁控溅射 二硼化镁     

HI—V族化合物半导体的高能重离子辐照缺陷研究·

用正电子湮没寿命谱技术研究了2.4×1O15/cm2、2.2×1016/cm2注量的85MeV19F离子辐照N型GaP和1.6×1016/cm 2注量的85MeV19F离子辐照P型InP所产生的辐照缺陷.结果表明:两种注量辐照在GaP中均产生较高浓度的单空位.其浓度随着辐照注量的增大而增加;辐照也在InP中产生较高浓度的单空位.     

求解一类非单调线性互补问题的宽邻域内点方法及其计算复杂性

对于一类非单调线性互补问题给出了一种新的算法——宽邻域内点算法，并讨论了其计算复杂性。     

Compression Behaviour of Ni77P23 Amorphous Alloy up to 30.5 GPa

The compression behaviour of Ni77P23 amorphous alloy is investigated at room temperature in a diamond-anvil cell instrument using in-situ high pressure energy dispersive x-ray diffraction with a synchrotron radiation source. The equation of state is determined by fitting the experimental data according to the Birch-Murnaghan equation. It is found that the structure of Ni77P23 amorphous alloy is stable under pressures up to 30.5 GPa. Within the pressure range from zero to the experimental one, the pressure-induced structural relaxation is reversible.     

Magnetic and Crystalline Microstructures of Fe-Pt-B Nanocomposite Ribbons

We investigate magnetic and crystalline microstructures of melt-spun (Fe0.675Pt0.325)100-xBx (x=12, 14, 16, 18,20) nanocomposite ribbons after optimal thermal treatment using a magnetic force microscope. The magnetic microstructures are characterized by darker spots adjacent to brighter ones in a sub-micro scale and in random distribution. It is found that the strength of the exchange coupling interaction between the crystals in the 10-100 nm scale, implied by the maximum value (δM)max of the Henkel plot, could be roughly described by the ratio of the average width of the magnetic spots w^- to the average crystal size D^- for the ribbons. Moreover, we find that the intrinsic coercivity jHc of the ribbons is sensitive to their crystal sizes, and the smaller D^-, the higher jHc. Finally, by using roughness analysis, the curve of the root mean square values (δФ)rms of the phase shift of the magnetic force images versus the boron content x is obtained, which is qualitatively consistent with that of the magnetization σ12 kOe of the ribbons versus x.     

Gd_xY_（1－x）P_5O_（14）：Ce，Tb的发光和能量传递Ⅱ．Ce→

研究了Ｇｄ＿ｘＹ＿（１－ｘ）Ｐ＿５Ｏ＿（１４）：Ｃｅ＿（０．０１），Ｔｂ＿（０．０２）体系中Ｇｄ的子晶格在Ｃｅ→Ｇｄ→Ｔｂ能量传递中的中介作用规律及ＧｄＰ＿５Ｏ＿（１４），ＧｄＰ＿５Ｏ＿（１４）：Ｃｅ，ＧｄＰ＿５Ｏ＿（１４）：Ｔｂ和Ｇｄ＿ｘＹ＿（１－ｘ）Ｐ＿５Ｏ＿（１４）：Ｃｅ，Ｔｂ的荧光光谱、激发光谱。结果表明，当ｘ＞０．７时，结构从单斜Ⅱ（Ｃ２／ｃ）的层状结构变为单斜Ｉ（Ｐ２＿１／ｃ）的带状结构，Ｃｅ￣（３＋）的发射光谱和Ｇｄ￣（３＋）的吸收光谱交迭增加等是Ｃｅ￣（３＋）→Ｇｄ￣（３＋）→Ｔｂ￣（３＋）能量传递几率增加的主要原因。     

牛顿弦截法预估校正迭代格式的收敛阶

研究如下形式的牛顿弦截法的预估校正(P.C.)格式:P(预估):~xk+1=xk-(xk-xk-1)f(xk)f(xk)-f(xk-1)C(校正):xk+1=xk-(~xk+1-xk)f(xk)f~(xk+1)-f(xk)证明了它的收敛阶为2.618.