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51.
The interaction spectrum is considered resulting from the near-resonance coupling of a small number of vibronic levels of two different electronic states. In the simple model proposed, the interactions between the near-resonance states are first explicitly considered and then the off-resonance interactions are treated by perturbation theory. The model is applied to the isoquinoline spectrum and it is shown that for isoquinoline the latter interactions may be safely ignored. Good agreement is achieved between the theoretical and experimental spectra, and many puzzling features, such as the irregular nature of the sequence structure and the ambiguous isotope effects are readily explained. The lowest excited singlet state is the nπ*, and it is located within about 1000 cm?1 of the first excited 1ππ*. Two vibronic levels of the 1nπ* state, corresponding to single quanta of the out-of-plane vibrations, are in near-resonance with the vibrationless 1ππ* level. 相似文献
52.
We investigated the flow field in a turbulent boundary layer in a flume, by using Particle Image Velocimetry (PIV) and Hot-Foil Infrared Imaging (HFIRI) techniques. Coherent patterns in the flow were identified and characterized by using instantaneous velocity and temperature fields. The velocity fields in the streamwise–spanwise plane were measured in parallel to the temperature distribution of the flume bottom. The identified patterns are represented by means of their spatial characteristics – a non-dimensional spatial separation between streamwise patterns, +. 相似文献
53.
R. M. Evich S. I. Perechinskii Z. P. Gad’mashi I. I. Shpak Yu. M. Vysochanskii V. Yu. Slivka 《Optics and Spectroscopy》2004,97(1):76-79
Rayleigh-Brillouin scattering in chalcogenide glasses of the Ge-As-S system was investigated for the (As2S3)100?x (GeS2)x (x=0–100) series. The longitudinal hypersonic velocities, adiabatic elasto-optical constants (p 12)ad at frequencies of about 15 GHz, and Landau–Placzek ratios (R LP) were determined. 相似文献
54.
We demonstrate a scheme for displacement measurement by use of the photoelectromotive force effect and a frequency-modulated laser diode. The measurement range can be adjusted by a change in the depth of frequency modulation, thus making the measurement method both simple and versatile. 相似文献
55.
Gad M. Landau Michal Ziv-Ukelson 《Journal of Algorithms in Cognition, Informatics and Logic》2001,41(2):338
The Common Substring Alignment Problem is defined as follows: Given a set of one or more strings S1, S2 … Sc and a target string T, Y is a common substring of all strings Si, that is, Si = BiYFi. The goal is to compute the similarity of all strings Si with T, without computing the part of Y again and again. Using the classical dynamic programming tables, each appearance of Y in a source string would require the computation of all the values in a dynamic programming table of size O(nℓ) where ℓ is the size of Y. Here we describe an algorithm which is composed of an encoding stage and an alignment stage. During the first stage, a data structure is constructed which encodes the comparison of Y with T. Then, during the alignment stage, for each comparison of a source Si with T, the pre-compiled data structure is used to speed up the part of Y. We show how to reduce the O(nℓ) alignment work, for each appearance of the common substring Y in a source string, to O(n)-at the cost of O(nℓ) encoding work, which is executed only once. 相似文献
56.
Journal of Cluster Science - The effective entrapment of drugs into nanoparticles is one of the most important features during nanoparticles preparation. The percentage loaded drug into the... 相似文献
57.
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59.
Riadh Dardouri Héla Habli Brahim Oujia Florent Xavier Gadéa 《Journal of computational chemistry》2013,34(24):2091-2099
For all states dissociating below the ionic limit Li? Rb+, we perform a diabatic study for 1Σ+ electronic states dissociating into Rb (5s, 5p, 4d, 6s, 6p, 5d, 7s, 4f) + Li (2s, 2p, 3s). Furthermore, we present the diabatic results for the 1–11 3σ, 1–8 1,3Π, and 1–4 1,3Δ states. The present calculations on the RbLi molecule are complementary to previous theoretical work on this system, including recently observed electronic states that had not been calculated previously. The calculations rely on ab‐initio pseudopotential, core polarization potential operators for the core‐valence correlation and full valence configuration interaction approaches, combined to an efficient diabatization procedure. For the low‐lying states, diabatic potentials and permanent dipole moments are analyzed, revealing the strong imprint of the ionic state in the 1Σ+ adiabatic states. The transition dipole moment is used to evaluate the radiative lifetimes of the vibrational levels trapped in the 2 1Σ+ excited states for the first time. In addition to the bound–bound contribution, the bound–free term has been evaluated using the Franck–Condon approximation and also exactly added to the total radiative lifetime. © 2013 Wiley Periodicals, Inc. 相似文献
60.
H. Habli H. Ghalla B. Oujia F.X. Gadéa 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,64(1):5-19
In the present work, all adiabatic potential energy curves, spectroscopic constants and
dipole moments of CaH+ molecular ion dissociating below the ionic limit
Ca2+H− are presented. These curves are determined by an ab initio
approach involving a non-empirical pseudo-potential for the Ca core, core-valence
correlation accounted in operator form with two types of core polarization potentials
(CPP) and full valence Configuration Interaction. The molecule is thus treated as a
two-electron system. The potential energy curves and the spectroscopic constants are
presented. In addition, the permanent and transition dipole moments are calculated for
most of the states and reveal the underlying ionic states. A rather good agreement with
the available theoretical works in the literature is obtained for the spectroscopic
constants of the lowest states of the CaH+ molecule. 相似文献