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61.
J.C. Pickering V. Zilio 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,13(2):181-185
High resolution spectra of neutral silver have been recorded by Fourier Transform Spectrometry in the region 2 000-8 280 ?(50
000-12 000 cm-1) with silver-neon and silver-argon hollow cathode lamps as sources. This work represents order-of-magnitude improvements,
compared to previous work on Ag I, in accuracy of transition wavelengths and wavenumbers, and energy level values. 35 classified
Ag I transitions are given, and the wavenumber uncertainty for the strongest lines is less than 0.002 cm-1. Improved values for 28 energy levels are presented.
Received 31 January 2000 and Received in final form 13 June 2000 相似文献
62.
The paper describes a new method for the calculation of the Sommerfeld screening parameter σ1. It requires neither the knowledge of the energy separations of spin doublet levels nor is it based on the application of
the Hertz law. The only data required for the calculation are the experimental energy values of the level concerned for the
series of elements belonging to the same subshell in which the element in the question is situated. As an illustration the
values of σ1 are calculated for the L
1, L
2 and L
3 levels for elements belonging to the 4f subshell and these are found to be in excellent agreement with those published earlier by Gokhale and Misra. The method brings
out the constancy of σ1 (L
2
L
3)−σ1(L
1) in a natural way and may thus be regarded as providing theoretical explanation of the Hertz law. 相似文献
63.
研究了涉及分担函数的正规定则,证明了:设F为定义在区域D内的一族亚纯函数,n,k是两个正整数,满足n≥k+3.如果对于F中任意一个函数f,(fn)((k))-z至多有一个不同的零点,则F在D内正规.此结论说明在(fn)((k))具有不动点的情形下,1990年杨乐在Notre Dame大学举行的学术会议上提出的断言仍然成立. 相似文献
64.
《Applied Mathematical Modelling》2014,38(5-6):1698-1709
We consider Bayesian estimation of the stress–strength reliability based on record values. The estimators are derived under the squared error loss function in the one parameter as well as two-parameter exponential distributions. The Bayes estimators are derived, in some cases in closed form, and their performance is investigated in terms of their bias and mean squared errors and compared with the maximum likelihood estimators. An illustrative example is given. 相似文献
65.
N. Pongali Sathya Prabu 《Phase Transitions》2013,86(7):592-607
In this study, complexes belonging to supramolecular hydrogen-bonded liquid crystal homologous series are synthesized and characterized. Hydrogen bond is formed between p-n-alkyloxy benzoic acids (nBAO, where n?=?5–11) and chlorobenzoic acid (ClBAO), respectively. The isolated homologues are characterized by various techniques such as polarizing optical microscopic (POM) studies, differential scanning calorimetry (DSC), and Fourier transform–infrared spectroscopy. Based on the POM and DSC studies, the phase diagram has been constructed and discussed. A new smectic ordering, labeled as smectic R, has been characterized, which exhibits a ribbon-like texture. This phase is observed in the complexes pertaining to the higher homologous series. Tilt angle in this phase has been experimentally deduced and the results are fitted to the power law which concurs with the mean-field theory predicted value. Optical shuttering action in the homologue has been detected in the nematic phase and the results are also discussed. 相似文献
66.
A. E. Kramida M.-C. Buchet-Poulizac 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,39(2):173-188
All experimental data on the
valence-shell-excited and core-excited spectra of Li-like neon, including
previously unpublished beam-foil spectroscopy data, have been compiled and
critically evaluated. Seventeen spectral lines have been newly identified.
Sets of recommended energy levels have been derived from the total list of
observed lines and from selected results of theoretical and semi-empirical
calculations. An accurate value of the ionization potential has been derived
from existing theoretical calculations.
Electronic supplementary material Online Material 相似文献
67.
This paper studies the idea of weighted sharing and proves two main theorems which generalize some results given by G. Brosch, Q. Zhang and other authors. 相似文献
68.
Vladimir Kapustin 《Journal of Functional Analysis》2006,238(1):313-326
In the first part of the paper we discuss a multi-dimensional analogue of the well-known construction by D. Clark that allows one to study families of spectral measures of perturbations of the model contraction. In the second part we present extensions of the relevant results on the boundary behavior of pseudocontinuable functions. We show that, although the most direct analogue of the scalar theorem on the existence of boundary values for pseudocontinuable functions with respect to Clark measures fails in the non-scalar situation, suitable vector-valued versions of such results can be found. 相似文献
69.
David Borwein Jonathan M. Borwein David M. Bradley 《Journal of Mathematical Analysis and Applications》2006,316(1):328-338
We consider some parametrized classes of multiple sums first studied by Euler. Identities between meromorphic functions of one or more variables in many cases account for reduction formulae for these sums. 相似文献
70.
In this paper, we establish a lower bound for the dimension of the vector spaces spanned over ? by 1 and the sums of the values of the Riemann zeta function at even and odd points. As a consequence, we obtain numerical results on the irrationality and linear independence of the sums of zeta values at even and odd points from a given interval of the positive integers. 相似文献