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1.
The present paper summarizes detailed investigations of Nd3+ fluorescence spectra in YAP:Nd laser crystal in the broad spectral range of 370–1100 nm at liquid nitrogen temperature. Especially, Nd3+ near UV and visible fluorescence spectra were studied for the first time in this crystal. The Nd3+ near UV and visible fluorescence spectra of this crystal consist of many narrow lines (up to 50). The Nd3+ near UV and visible fluorescence lines arise mainly from4D3/2 and2P3/2 Nd3+ terms (transitions from4D3/2,2P3/2 to lower lying Nd3+ levels are responsible for their appearance). At room temperature the fluorescence spectra consist of broad bands with narrow lines (mainly4D3/24F3/2,4F5/2 and2H9/2 transitions). 相似文献
2.
Summary The existence of a joint asymptotic distribution for the windings of a three-dimensional Brownian motion around a finite number of straight lines is obtained. This complements the recent studies, by Pitman- Yor, and the authors, of the joint asymptotic distribution for the windings of planar Brownian motion around a finite number of points.The following principle governs the passage from results in the plane to results in space:Let B be a three-dimensional Brownian motion, and P
1, ..., P
k, k planes which intersect two by two. Then, the convergences in distribution concerning the planar Brownian motions B
i (1ik), defined respectively as the orthogonal projections of B on P
i (1ik), take place jointly, and the corresponding limit variables are independent. 相似文献
3.
B. Hlavőček J. Šestők L. Koudelka P. Mošner J. J. Mareš 《Journal of Thermal Analysis and Calorimetry》2005,80(2):271-283
Summary The forms of vibrations and displacements of particles in amorphous structures have been investigated. The particles, moving on highly non-linear amplitude, are responsible for the creation of disordered structures of amorphous bodies. The non-linear oscillators, even if 'few' in concentration, are characterized by unpredictable trajectories in phase space. The non-linear oscillators are fully developed in the liquid state above the crossover temperature Tcr and between Tcr and Tg their number decreases. Under Tg they completely disappear. The interconnection between the linear oscillators in blocks plays the most important role in the characteristic time spectra in liquid state. Using the additive properties of elements polarizibilities, the number of acoustical units in individual blocks at Tcr is estimated to be about 600 units. The diameter of blocks at Tcr was estimated to be about 1.8 nm. Even if the non-linear high amplitude motions disappear at solidification, the remnants of structural irregularity remain and the disordered structure of glass is formed. 相似文献
4.
An electrochemical method for the determination of the ionophores monensin and lasalocid was developed, based on the polarization of an agar gel/nitrobenzene electrolyte interface. The measured current corresponding to the facilitated ion transfer across this interface is directly proportional to the concentration of an ionophore dissolved in the organic phase. Using cyclic voltammetry in a three-electrode system the detection limit for both ionophores is about 3 × 10?5 M. 相似文献
5.
Characteristics of multi- hypernuclei are investigated within the relativistic mean-field theory. Both linear and nonlinear models and a variety of couplings fitted to ordinary hypernuclei have been investigated. All the parametrizations used in the present work predict qualitatively similar dependence of the studied quantities (rms radii, binding energies, densities) on a number of hyperons.Deceased on May 5, 1991 相似文献
6.
J. Adam Jr. J. Mareš O. Richter M. Sotona S. Frullani 《Czechoslovak Journal of Physics》1992,42(11):1167-1196
Formalism for the electroproduction of strange particles based on the one photon exchange approximation and the Feynman diagrams representation of hadron current is reviewed. Different photoproduction models are compared with available photo and electroproduction data. New experiments are proposed that may resolve existing uncertainties and inconsistencies. The formation of hypernuclei via kaon electroproduction is investigated theoretically and compared with other reactions involving purely hadronic processes. 相似文献
7.
8.
We show a large deviations principle for the family of random variables
when t+, where B=(B
u
,u0) is a standard linear Brownian motion. 相似文献
9.
We consider the asymptotic behavior of semi-stable Markov processes valued in ]0,[ when the starting point tends to 0. The entrance distribution is expressed in terms of the exponential functional of the underlying Lévy process which appears in Lamperti's representation of a semi-stable Markov process. 相似文献
10.
The principles of electrolysis and facilitated ion transfer at the interface of two immiscible electrolyte solutions are outlined. The method of determination of ionophores is exemplified by assay of monensin in cultures ofStreptomyces cinnamonensis.Dedicated to Professor W. Simon on the occasion of his 60th birthday 相似文献