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961.
The complex-scaled Green's function(CGF)method is employed to explore the single-proton resonance in 15F.Special attention is paid to the first excited resonant state 5/2+,which has been widely studied in both theory and experiments.However,past studies generally overestimated the width of the 5/2+state.The predicted energy and width of the first excited resonant state 5/2+by the CGF method are both in good agreement with the experimental value and close to Fortune's new estimation.Furthermore,the influence of the potential parameters and quadruple deformation effects on the resonant states are investigated in detail,which is helpful to the study of the shell structure evolution. 相似文献
962.
绝缘问题是高电压、高场强器件和设备中不可回避的问题,是决定器件、设备运行参数和稳定性的重要因素。针对一台直线感应加速器调试中出现的加速腔绝缘环在带束负载情况下的真空沿面闪络现象,进行了分析和研究。分析表明,在排除设计、材料、加工、洁净和真空度等常规异常因素后,导致绝缘环真空沿面闪络的可能因素是电子在绝缘环表面的吸附和累积,绝缘环上累积的电子来源和加速器中加速、传输的电子束的丢失有关。从加速腔工作状态出发,分析绝缘环表面积累电荷和丢失电子束的相关途径,进而提出相应的技术措施,以提高加速腔运行稳定性。 相似文献
963.
Wei-Xue Shi 《Proceedings of the American Mathematical Society》1999,127(2):615-618
In this paper, we prove that if a perfect GO-space has a -discrete dense set, then has a perfect linearly ordered extension. This answers a problem raised by H. R. Bennett, D. J. Lutzer and S. Purisch. And the result is also a partial answer to an old problem posed by H. R. Bennett and D. J. Lutzer.
964.
X-ray absorption investigation of the site occupancies of the copper element in nominal Cu_3Zn(OH)_6FBr 下载免费PDF全文
Ruitang Wang Xiaoting Li Xin Han Jiaqi Lin Yong Wang Tian Qian Hong Ding Youguo Shi Xuerong Liu 《中国物理 B》2021,(4):440-445
With Zn substitution to the three-dimensional antiferromagnetically ordered barlowite Cu_4(OH)_6 FBr,Cu_3 Zn(OH)_6 FBr shows no magnetic phase transition down to 50 mK,and the system is suggested to be a two-dimensional kagome quantum spin liquid [Chin.Phys.Lett.34 077502(2017)].A key issue to identify such phase diagram is the exact chemical formula of the substituted compound.With Cu L-edge x-ray absorption spectrum(XAS) combined with the MultiX XAS calculations,we evaluate the Cu concentration in a nominal Cu_3 Zn(OH)_6 FBr sample.Our results show that although the Cu concentration is 2.80,close to the expected value,there is 34% residual Cu occupation in intersite layers between kagome layers.Thus the Zn substitution of the intersite layers is not complete,and likely it intrudes the kagome layers. 相似文献
965.
The single 2 dilation wavelet multipliers in one-dimensional case and single A-dilation (where A is any expansive matrix with integer entries and |detA| = 2) wavelet multipliers in twodimensional case were completely characterized by Wutam Consortium (1998) and Li Z., et al.
(2010). But there exist no results on multivariate wavelet multipliers corresponding to integer expansive dilation matrix
with the absolute value of determinant not 2 in L
2(ℝ2). In this paper, we choose $2I_2 = \left( {{*{20}c}
2 & 0 \\
0 & 2 \\
} \right)$2I_2 = \left( {\begin{array}{*{20}c}
2 & 0 \\
0 & 2 \\
\end{array} } \right) as the dilation matrix and consider the 2I
2-dilation multivariate wavelet Φ = {ψ
1, ψ
2, ψ
3}(which is called a dyadic bivariate wavelet) multipliers. Here we call a measurable function family f = {f
1, f
2, f
3} a dyadic bivariate wavelet multiplier if Y1 = { F - 1 ( f1 [^(y1 )] ),F - 1 ( f2 [^(y2 )] ),F - 1 ( f3 [^(y3 )] ) }\Psi _1 = \left\{ {\mathcal{F}^{ - 1} \left( {f_1 \widehat{\psi _1 }} \right),\mathcal{F}^{ - 1} \left( {f_2 \widehat{\psi _2 }} \right),\mathcal{F}^{ - 1} \left( {f_3 \widehat{\psi _3 }} \right)} \right\} is a dyadic bivariate wavelet for any dyadic bivariate wavelet Φ = {ψ
1, ψ
2, ψ
3}, where [^(f)]\hat f and F
−1 denote the Fourier transform and the inverse transform of function f respectively. We study dyadic bivariate wavelet multipliers, and give some conditions for dyadic bivariate wavelet multipliers.
We also give concrete forms of linear phases of dyadic MRA bivariate wavelets. 相似文献
966.
967.
BL代数的fantastic滤子和normal滤子 总被引:1,自引:0,他引:1
滤子是研究逻辑代数的有效工具.本文研究了BL代数的fantastic和normal滤子的等价条件,得到了在MV-代数中两种滤子之间的等价性,给出了两个公开问题:"在什么样的合适条件下,一个normal滤子成为一个fantastic滤子?"和"在什么合适的条件下,normal滤子的拓展性成立?"结论成立的一种条件. 相似文献
968.
In this paper, we are concerned with the existence and uniqueness of global smooth solution for the Robin boundary value problem of Landau-Lifshitz equations in one dimension when the boundary value depends on time t. Furthermore, by viscosity vanishing approach, we get the existence and uniqueness of the problem without Gilbert damping term when the boundary value is independent of t. 相似文献
969.
J.-J. Shi B.C. Sanders S.-H. Pan 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,4(1):113-119
We calculate the electron-phonon scattering rate for an asymmetric double barrier resonant tunneling structure based on dielectric
continuum theory, including all phonon modes, and show that interface phonons contribute much more to the scattering rate
than do bulk-like LO phonons for incident energies which are approximately within an order of magnitude of the Fermi energy.
The maximum scattering rate occurs for incident electron energies near the quantum well resonance. Subband nonparabolicity
has a significant influence on electron-phonon scattering in these structures. We show that the relaxation time is comparable
to the dwell time of electrons in the quantum well for a typical resonant tunneling structure.
Received: 23 December 1997 / Revised: 24 March 1998 / Accepted: 9 March 1998 相似文献
970.