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71.
采用分子束外延技术(MBE)在MgO(001)基板上沉积了氧化铬薄膜,并利用x射线衍射 (XRD)和x射线反射谱(XRR)对薄膜的晶体结构进行了表征.θ—2θ扫描和倒易空间图(R SM)揭示出薄膜为单相c轴外延生长,晶体结构为体心正交,晶胞常数a,b,c分别为0.8940±0.0003,0.298±0.0002和0.3897±0.0002nm.扫描表明薄膜在面内具有90°孪晶,取向关系为a∥MgO〈110〉,c∥MgO(001).XRR谱测得薄膜的电子 密度为1350±20nm-3,与由晶胞体积 计算得
关键词:
一氧化铬薄膜
x射线衍射
倒易空间图
x射线反射谱 相似文献
72.
Fe ions were implanted into α-Al2O3 single crystals (sapphire) at room temperature and annealed in a reducing atmosphere. The orientation relationships (ORs) between α-Fe particles and sapphire matrix were investigated using transmission electron microscopy (TEM). All the α-Fe particles have the orientation relationship (OR) of (1 1 1)α-Fe || (0 0 0 1)sapphire and with sapphire. This OR is predicted precisely by the coincidence of reciprocal lattice points (CRLP) method. The other OR of (1 1 0)α-Fe || (0 0 0 1)sapphire and reported before is confirmed by the same method to be one of the secondary preferred orientation relationships in the α-Fe/sapphire system. 相似文献
73.
The Qiao--Liu equation with self-consistent sources (QLESCS) and its Lax representation are derived. A reciprocal transformation for the QLESCS is given. By making use of the reciprocal transformation and the solutions of the mKdV equation with self-consistent sources (mKdVSCS), the solutions of the QLESCS are presented. 相似文献
74.
This paper discusses the approximation by reciprocals of polynomials with positive coefficients in Orlicz spaces and proved that if f(x) ∈ LM*[0,1], changes its sign at most once in (0,1), then there exists x0 ∈ (0,1) and a polynomial Pn ∈ Πn(+) such that f (x) -Pn (x)x-x0 M ≤ Cω( f,n-1/2 )M, where Πn(+) indicates the set of all polynomials of degree n with positive coefficients. 相似文献
75.
The method of non-standard analysis(NSA) is used to construct a pair of hyperstandard reciprocal formulas involving certain non-standard difference operators with realnumber orders.Our main result consists of some extensions of earlier results appearing previously [5].An essential meaning of the paper is to indicate the fact that only the basic idea of NSA is applicable to the construction of a unified pattern that may have certain applications to both the analysis and the number theory. 相似文献
76.
77.
78.
求出了一些与广义Fibonacci,Lucas数有关的一些倒数级数的值。 相似文献
79.
A New Integrable Equation with Peakon Solutions 总被引:5,自引:0,他引:5
We consider a new partial differential equation recently obtained by Degasperis and Procesi using the method of asymptotic integrability; this equation has a form similar to the Camassa–Holm shallow water wave equation. We prove the exact integrability of the new equation by constructing its Lax pair and explain its relation to a negative flow in the Kaup–Kupershmidt hierarchy via a reciprocal transformation. The infinite sequence of conserved quantities is derived together with a proposed bi-Hamiltonian structure. The equation admits exact solutions as a superposition of multipeakons, and we describe the integrable finite-dimensional peakon dynamics and compare it with the analogous results for Camassa–Holm peakons. 相似文献
80.
We present a new construction of the Student and Student-like fractal activity time model for risky asset. The construction uses the diffusion processes and their superpositions and allows for specified exact Student or Student-like marginal distributions of the returns and for flexible and tractable dependence structure. The fractal activity time is asymptotically self-similar, which is a desired feature seen in practice. 相似文献