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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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Nuclear ground state spins of the odd-mass strontium isotopes between A=79 and 97 were determined by measurements of the hyperfine structure in the ionic transition 5s2S1/2?5p2P3/2. The spins of93Sr and97Sr are revised to I=5/2 and I=1/2, respectively, while assignments for the remaining isotopes are confirmed.  相似文献   
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Collinear laser—fast alkaline-earth ion beam interaction can be monitored sensitively by a detection sequence consisting of optical pumping to a metastable state, state-dependent neutralization, and separate counting of ions and atoms. Deceleration of the ions prior to neutralization strongly increases the sensitivity of the method. For ions with hyperfine split transitions the sensitivity can be considerably improved by a two-step optical pumping sequence. In this contribution, the results of rate equation calculations are compared to experimental results for Ba-and Sr-beams, including a shortlived99Sr beam of very low intensity.  相似文献   
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The hyperfine structure of the metastable 5d 2 D 3/2 state has been measured with high precision by collinear laser-rf double resonance spectroscopy on fast135,137Ba ion beams. The present data are about 100 times more accurate than those obtained by classical fast beam laser spectroscopy.  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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