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991.
992.
993.
We present magneto-optical (MO) Faraday spectra measured around the M2,3 edges (60-70eV) of Ni films at the Beijing Synchrotron Radiation Facility (BSI~F). A polarization analysis of the final state of the transmitted radiation from the Ni film is employed to determine the Faraday rotation at the edges. The MO effect becomes resonantly enhanced at the M2,3 edges, and accordingly large values for the rotation angle β of 1.85 ± 0.19° for this ferromagnetic Ni film with thickness of 31 nm are measured. Without the magnetic field, the azimuthal angles do not shift; with parallel and antiparallel magnetic field the rotation angles shift in the opposite way and they are symmetrical. The uncertainty of Faraday rotation angles mainly comes from the data fitting and the state change of the beamline when the angles are measured. 相似文献
994.
IIntroductlonMuch work has been done on the asymptotlcbehavlor of*theotlcbehavlor second orderdl地rentlal equation.Some results oflt are based on the Integral Inequalities’of G。"wall-B<bar<type.Kong Qingkal[11 has studledthe behavior ofa classofnonllnear dl地rentlal equations ofnth order.Some people[2;3]h肌e studiedthe asymptotlc behavior of the second order nonlinear difference equations.Atpresent,papers about the asymptotlc behavior of nonlinear difference equatlons of nib order … 相似文献
995.
As shown by an example, the integral function f :
n
, defined by f(x) = a
b[B(x, t)]+
g(t) dt, may not be a strongly semismooth function, even if g(t) 1 and B is a quadratic polynomial with respect to t and infinitely many times smooth with respect to x. We show that f is a strongly semismooth function if g is continuous and B is affine with respect to t and strongly semismooth with respect to x, i.e., B(x, t) = u(x)t + v(x), where u and v are two strongly semismooth functions in
n
. We also show that f is not a piecewise smooth function if u and v are two linearly independent linear functions, g is continuous and g 0 in [a, b], and n 2. We apply the first result to the edge convex minimum norm network interpolation problem, which is a two-dimensional interpolation problem. 相似文献
996.
提出了一种利用锯齿波激励以增强超声造影剂微气泡激发的次谐波信噪比的方法。基于修正的Church方程,采用数值计算分析了锯齿波激励下微气泡产生的次谐波的声压阈值及变化特性,并与正弦波激励进行了比较。实验中采用声压相等的基频为2 MHz的锯齿波及正弦波激发一种自制的包膜微气泡造影剂,测量了产生次谐波的激励声压阈值及与激励声压的关系。结果表明,锯齿波信号激励可以增强次谐波信号的强度,相对于正弦波激励增强约13 dB,并且激发声压阈值较低。实验结果与数值计算结果相符。 相似文献
997.
998.
离心压气机叶片扩压器气动优化设计 总被引:3,自引:0,他引:3
本文以某高速离心压气机叶片扩压器为研究对象,采用Kriging模型在设计工况下对其进行气动优化设计,以获取较高的"叶轮 扩压器"等熵效率,同时保证扩压器出口静压不降.Kriging模型大大加速了设计过程,得到的优化结果和原始设计相比,在性能上有了较大改善. 相似文献
999.
EAST���ϲ��Ͼ�Ե����������Ԫ���� 总被引:3,自引:1,他引:3
用有限元法对EAST装置磁体系统的高性能氦气密复合材料绝缘子性能作了全面的分析.结果表明:绝缘子可满足承受EAST装置耐电压15kV的使用要求;热应力对绝缘子的绝缘层影响最大,外力对绝缘层应力的影响可忽略;EAST复合材料绝缘子具有优良的低温力学性能. 相似文献
1000.
A novel binuclear cobalt complex with mixed valence state Co(Ⅰ)Co(Ⅱ)(μ-Ph_2Ppy)_2(μ-CO)_2Cl_3 has been prepared, Ph_2Ppy=2-(diphenyl phosphino)pyridine, and its molecular structure determined by using 3569 independent reflections. The complex was crystallized in the orthorhomblc space group P2_1nb with a=13.32(1), b=14.31(1),c=18.94(2) and Z=4. The structure was solved by direct method and full-matrix least squares refinement carried out. The final R value is 0.072.If the Co-Co bond is not taken into account, two cobalt atoms exhibit a five-coordlnate reformed trigonal bipyramid configuration (formal oxidation state +1) and a six-coordinate reformed octahedral configuration (formal oxidation state +2), respectively. The Co-Co distance is 2.685(1). The molecule belongs to the C_(2v), point group. A new W-frame compound with mixed valence state Co(0)Co(Ⅰ)(μ-Ph_2Ppy)_2(μ-CO)(CO)Cl can be formed by reducing this complex. 相似文献