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31.
《Indagationes Mathematicae》2022,33(6):1221-1235
In a recent paper (Temme, 2021) new asymptotic expansions are given for the Kummer functions and for large positive values of and , with fixed and special attention for the case . In this paper we extend the approach and also accept large values of . The new expansions are valid when at least one of the parameters , , or is large. We provide numerical tables to show the performance of the expansions. 相似文献
32.
《International Journal of Solids and Structures》2014,51(25-26):4452-4461
This paper brings a comparative analysis between dynamic models of couple-stress elastic materials and structured Rayleigh beams on a Winkler foundation. Although physical phenomena have different physical origins, the underlying equations appear to be similar, and hence mathematical models have a lot in common. In the present work, our main focus is on the analysis of dispersive waves, band-gaps and localised waveforms in structured Rayleigh beams. The Rayleigh beam theory includes the effects of rotational inertia which are neglected in the Euler–Bernoulli beam theory. This makes the approach applicable to higher frequency regimes. Special attention is given to waves in pre-stressed Rayleigh beams on elastic foundations. 相似文献
33.
Shanshan Sun Litao Wang Jiasheng Wang Wenjing Lv Qinghua Yu Dong Pei Siqi Han Xingyu Li Miao Wang Sheng Liu Xiangao Quan Mei Lv 《Journal of separation science》2023,46(16):2200935
In this work, homochiral reduced imine cage was covalently bonded to the surface of the silica to prepare a novel high-performance liquid chromatography stationary phase, which was applied for the multiple separation modes such as normal phase, reversed-phase, ion exchange, and hydrophilic interaction chromatography. The successful preparation of the homochiral reduced imine cage bonded silica stationary phase was confirmed by performing a series of methods including X-ray photoelectron spectroscopy, thermogravimetric analysis, and infrared spectroscopy. From the extracted results of the chiral resolution in normal phase and reversed-phase modes, it was demonstrated that seven chiral compounds were successfully separated, among which the resolution of 1-phenylethanol reached the value of 3.97. Moreover, the multifunctional chromatographic performance of the new molecular cage stationary phase was systematically investigated in the modes of reversed-phase, ion exchange, and hydrophilic interaction chromatography for the separation and analysis of a total of 59 compounds in eight classes. This work demonstrated that the homochiral reduced imine cage not only achieved multiseparation modes and multiseparation functions performance with high stability, but also expanded the application of the organic molecular cage in the field of liquid chromatography. 相似文献
34.
Shijun Zheng 《分析论及其应用》2006,22(4)
Let H be a Schr(o)dinger operator on Rn. Under a polynomial decay condition for the kernel of its spectral operator, we show that the Besov spaces and Triebel-Lizorkin spaces associated with H are well defined. We further give a Littlewood-Paley characterization of Lp spaces in terms of dyadic functions of H. This generalizes and strengthens the previous result when the heat kernel of H satisfies certain upper Gaussian bound. 相似文献
35.
文章合成了Lu(NO3)3(C2H5O2N)4.H2O,用红外和元素分析对其进行了表征。用高精度全自动绝热量热仪,测定了该配合物80-382 K温区的热容, 利用实验热容数据, 根据热容与焓、熵的热力学关系, 求出了配合物85-350 K温区内每隔5 K相对于298.15K的标准热力学函数(HT - H298.15)m和(ST - S298.15)m.在80-350 K温度区间内,配合物的热容随温度升高而增大,没有相转移点和热力学吸收峰的出现,该配合物在此温度区间内是稳定存在的。 相似文献
36.
Sabyasachi Kar Yu‐Shu Wang Wei‐Qi Li Xiu‐Dong Sun 《International journal of quantum chemistry》2015,115(22):1573-1579
The effect of plasma screening on the dynamic dipole polarizability (DPP) of two‐electron ions Be2+, B3+, and C4+ has been investigated using highly correlated exponential wave functions within the framework of pseudostate summation technique and Debye screening concept. Plasma‐screening effect on the oscillator strengths (OS) of the ultraviolet and visible series has also been investigated for the systems Li+, Be2+, B3+, C4+. The DPP are reported as functions of screening parameters. The OS for S‐P transitions are also reported for various screening parameters. The OS and dynamic polarizability show interesting behavior with increasing screening strength and nuclear charge. © 2015 Wiley Periodicals, Inc. 相似文献
37.
Deuteron electromagnetic form factors and tensor polarization observables in the framework of the hard-wall AdS/QCD model 下载免费PDF全文
We study the electromagnetic form factors and tensor polarization observables of the deuteron in the framework of the hard-wall AdS/QCD model. We find a profile function for the bulk twist \begin{document}$\tau=6$\end{document} ![]()
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vector field, which describes the deuteron on the boundary and fix the infrared boundary cut-off of AdS space in accordance with the ground state mass of the deuteron. We obtain the deuteron charge monopole, quadrupole, and magnetic dipole form factors and tensor polarization observables from the bulk Lagrangians for the deuteron and photon field interactions. We plot the momentum transfer dependence of the form factors and tensor polarization observables and compare our numerical results with those in the soft-wall model and experimental data. 相似文献
38.
Lingyun GAO 《数学物理学报(B辑英文版)》2017,37(1):187-194
In this paper, we will mainly investigate entire solutions with finite order of two types of systems of differential-difference equations, and obtain some interesting results. It extends some results concerning complex differential (difference) equations to the systems of differential-difference equations. 相似文献
39.
40.
本文研究了复线性微分方程解的增长性问题.利用两类具有某种渐进增长性质的函数作为线性微分方程的系数,讨论了两类二阶线性微分方程解的增长性,获得了方程解为无穷级.这些结果推广了先前的一些结果. 相似文献