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Autoionizing Rydberg series of Li2 have been observed in the two-step optical cxcitation of a supersonic lithium beam. The series limits are vibrational states of Li2+. In the most probable assignment IP(Li2) = 41236.4 ± 2.5 cm?1 and for Li2+ωe = 263.45 ± 1.3 cm?1; ωeχe = 1.35 ± O.2 cm?1; re = 3.032 ± 0.01 Å; De = 10807 ± 150 cm?1.  相似文献   
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In this paper we extend the plane blow-up results of Grundy& McLaughlin (1997) to the three-dimensional Navier-Stokes equations.Using a solution structure originally due to Lin we first providenumerical evidence for the existence of blow-up solutions on- < x, z < , 0 y 1 with boundary conditions on y = 0and y = 1 involving derivatives of the velocity components.The formulation enables us to consider plane and radial flowas special cases. Various features of the computations are isolatedand are used to construct a formal asymptotic solution closeto blow-up. We show that the numerical and asymptotic analysesprovide a mutually consistent global picture which supportsthe conclusion that, for the family of problems we considerhere, blow-up in fact can take place in three dimensions butat an inverse linear rate rather than the faster inverse squareof the plane case.  相似文献   
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Ice nucleating-active Pseudomonas fluorescens F264C was fed to Colorado potato beetles to determine bacterial retentioin in the beetle gut and its effect on the cold hardiness of this insect pest. The bacrterium was present in beetles recovered after overwintering in the field, seven months after their exposure to P. fluorescens. Retention was evident not only in the detection of the P. fluorescens ice nucleating gene, inaW, in bacterial cultures from beetle guts but also in the elevated supercooling points of some treated beetles.  相似文献   
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The velocity dependence of the total scattering cross section has been measured for 10 different combinations of alkali atoms with rare gas atoms. By means of an automated fast comparison technique the precision of relative values ofQ(ν) can be increased to 10?3. In the eight cases where Ar, Kr or Xe is the scattering gas, undulations ofQ(ν) about its mean value have been observed. The precision of the method allows us in these cases to extract reliable information on the amplitude of the undulations. Use of this additional information makes it impossible to explain the experimental results with the simple, 2- or 3-parameter potentials that are generally used. Deferring a final evaluation to a later paper, we restrict ourselves here to giving, for the Lennard-Jones (8?6) potential, a table of?r m values.  相似文献   
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The Stark effect of a rotating anharmonic oscillator is calculated including terms up to 10?7 relative accuracy for comparison with recent high precision experiments. A series expansion is used for the internuclear potential and the instantaneous dipole moment as a function ofr, the nuclear distance. The measurable effects are
  1. 1.
    the change of the dipole moment with the vibrational quantum numberv up to terms proportional to (v + 1/2)2;  相似文献   
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HARUN REŞIT YAZAR 《Pramana》2013,81(4):579-585
The sd-interacting boson approximation (sd-IBA) and the df-interacting boson approximation (df-IBA) can be related to each other and the states of the interacting boson approximation model can be identified with the fully symmetric states in the sdf interacting boson approximation model. A systematic study of the sdf-IBA model showed that the constructed Hamiltonian can successfully describe the strong octupole correlations in the deformed nuclei. We showed that the interacting boson approximation may account for many of these K π ?=?0+ states. It was found that the calculated energy spectra of the gadolinium isotopes agree quite well with the experimental data. The observed B(E2) values were also calculated and compared with the experimental data.  相似文献   
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5-Geranoxypsoralen, commonly called bergamottin, a major furocoumarin contained in bergamot oil, is reported in vitro as a highly photoreactive psoralen. In ethanol, it exhibits quite a high triplet state quantum yield (approximately 0.37). The triplet state is involved in subsequent photochemistry which depends on the initial concentration and on the presence of oxygen. In contrast to most psoralens, absorption and fluorescence data suggest that 5-geranoxypsoralen does not interact with DNA in the dark. No UVA-induced interstrand cross-links in DNA were shown.  相似文献   
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Dual-detector differential non-destructive Fourier transform detection in a quadrupole ion trap is shown to improve signal intensity and reduce noise compared with spectra recorded using a single detector. A larger area detector in each end-cap electrode is machined to fit its hyperbolic shape and so minimize field imperfections on the z-axis. Argon, acetophenone and bromobenzene spectra were recorded to allow a comparison between single- and dual-detector (differential) modes of detection and to demonstrate the improvement achieved with differential detection. Copyright 1999 John Wiley & Sons, Ltd.  相似文献   
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