共查询到16条相似文献,搜索用时 156 毫秒
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用内转换电子穆斯堡尔谱(CEMS)和慢正电子束研究了含3%Y2O3的ZrO2中57Fe离子(100keV,3×1016at./cm2)注入态及其在氢气氛中退火的热力学行为.注入态以Fe3+,Fe2+和Fe0存在,它们分别是Fe3+-V(空位)复合体、二聚体和超顺磁颗粒.经400,500℃退火后,Fe3+-V分解,分别出现了α-Fe的前期相和α-Fe纳米颗粒.含Fe的ZrO2(Y)混合导电的出现可能是和Fe的不同价态及其相对含量有关
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27keV Ar+离子束沿法向分别入射在BaF2单晶(111),(100)和(110)的晶面上,用捕获器方法和Rutherford背散射分析法测定了Ba原子的溅射角分布和溅射产额。结果发现不同取向的晶体表面,它们的溅射产额有明显差异。当用剂量为5×1017ion/cm2的Ar+离子分别轰击这三种晶面时,其溅射产额的顺序Y100>y111>y110.对已被上述剂量辐照过的晶面再作相同剂量轰击时,测得的溅射产额明显增大。这些结果被认为是由于在离子辐照过程中表面晶格受损逐步增大所致。
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提出校正回火金属玻璃(非晶合金)小角x射线散射强度的背底误差的方法:将淬火态非晶合金的小角X射线散射强度作为在相同的实验条件下得到的回火非晶合金小角X射线散射强度的背底而予以扣除。并将这样扣除背底和用通常方法扣除背底得到的结果相比较,由前者得到的散射强度遵从Porod律,并进而得到Porod常数Kp=4.6×10-2(nm-3),积分不变量Qs=1.63(nm-2),比内表面Sp=84m2/cm3,Porod半径Rp=4.4nm用通常方法扣除背底后的散射强度不满足Porod规律。
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分别采用6-31G*,6-31G?*基组对线性ArCN分子的X2∑+,A2∏i,B2∑+,C2∏i,D2∑+和E2∏r 6个电子态进行了从头计算法开壳自旋限制Hartree-Fock(ROHF)计算。计算结果表明线性ArCN分子的电子态具有典型的准分子结构,从而可以肯定CN与稀有气体原子Rg(Ar,Kr,Xe)能够形成自由基准分子。对X2∑+,A2∏i的自旋非限制Hartree-Fock(UHF)计算证实较大的自旋污染不影响势能曲线的形状。
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提出了用单频导纳谱法测量储硅单量子阶的能带偏移,与常规的多频导纳谱相比,它只需测一个频率的导纳谱就能得到更精确的实验结果。用该方法对Si/Ge0.33Si0.67/Si单量子阱进行测试,得到激活能为Ea=0.20eV。为了计算出能带偏移值,必须能准确确定具有单量子阱结构样品中的费密能级位置,由于在单量子阱结构中费密能级的位置与阱材料、垒材料的掺杂浓度、阱的高度(即能带偏移)及温度等几个因素均有关。为此,本文通过解泊松方程,计算出结合本文样品
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A. M. Parshin V. A. Gunyakov V. Ya. Zyryanov V. F. Shabanov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(8):1045-1048
The change in the domain texture of the 5CB nematic liquid crystal on the surface of a polyvinyl butyral gelatinous polymer
solution cured in a magnetic field is studied optically. The alignment of the nematic is described by the effective order
parameter S* of the polydomain cells. The anchoring energy of a liquid crystal with gelatinous polymer W
ϕ = 1 × 10−3 erg/cm2 is determined. 相似文献
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Gunyakov VA Parshin AM Shabanov VF 《The European physical journal. E, Soft matter》2006,20(4):467-473
Specific features of the anisotropic interaction between a nematic mixture and a polar surface of a ferroelectric triglycine
sulfate crystal have been studied over a wide temperature range including the substrate's Curie point Tc. The mixture was composed of two nematic liquid crystals, 60% of p-methoxybenzylidene-p-n-butylaniline (MBBA) and 40% of p-ethoxybenzylidene-p-n-butylaniline (EBBA), and doped with a small amount of a dichroic dye. The temperature dependence of the polarized components
of optical density Dj of the dye absorption band for the nematic and isotropic phases of the MBBA+EBBA mixture has been obtained using polarization
optic techniques. The temperature-induced structural changes in the nematic layer near Tc were found to be related to the changes in the orientational part of the tensor order parameter Qik. The experimental data have been interpreted using the model, in which the dispersive van der Waals forces of the substrate
stabilize the planar orientation of the nematic in the bulk competing with the short-range anchoring forces in the vicinity
of Tc. At the same time, the anisotropic part of the surface energy has two terms with the orthogonal easy axes. The nature of
the surface electric field and its effect on the director alignment at the interface have been clarified. Taking into account
the known relation between anchoring strength and the nematic order parameter, the effective anchoring energy weff for the studied system has been determined as a function of temperature. 相似文献