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31.
J.-J. Bonnet D. Hubert F. Bonnet M. Bonnefoy A. Fleury L. Avan 《Physics letters. A》1979,70(2):99-102
This note presents the first measurement of the relative intensities of the radiative processes of the L shell of argon. The partial emission cross sections are deduced. Our data show that the radiative transitions within the excited ion are very sensitive to the incident electron energy. 相似文献
32.
Loutelier-Bourhis C Legros H Bonnet JJ Costentin J Lange CM 《Rapid communications in mass spectrometry : RCM》2004,18(5):571-576
The ex vivo identification of dopaminergic metabolites present in rat striata after (L-DOPA + benserazide) treatment is reported. The different metabolites have been identified as the trimethylsilyl derivatives in the striatal extracts by gas chromatography/mass spectrometry. 相似文献
33.
Let b denote the unboundedness number of ωω. That is, b is the smallest cardinality of a subset
such that for everyg∈ωω there isf ∈ F such that {n: g(n) ≤ f(n)}is infinite. A Boolean algebraB is wellgenerated, if it has a well-founded sublatticeL such thatL generatesB. We show that it is consistent with ZFC that
, and there is a Boolean algebraB such thatB is not well-generated, andB is superatomic with cardinal sequence 〈ℵ0, ℵ1, ℵ1, 1〉. This result is motivated by the fact that if the cardinal sequence of a Boolean algebraB is 〈ℵ0, ℵ0, λ, 1〉, andB is not well-generated, then λ≥b. 相似文献
34.
Borohydride complexes of the rare earths have attracted increasing interest during the last decade. This review aims to cover recent results over this period with respect to the preparation, characterization, structure, and applications in organic chemistry of this family of compounds, including inorganic and organometallic complexes. Special emphasis is made on their use for polymerization catalysis. 相似文献
35.
This paper presents longitudinal space and space-time conventional velocity correlations measured in the wake of a two-dimensional flat-plate at zero incidence, with fully-turbulent boundary layers at its sharp trailing edge. Iso-correlation contour plots are given in the plane of symmetry and normal to this plane in the assumed asymptotic (in the mean velocity sense) part. Comparisons with initially laminar 2-D wake results show that the classical Double-Roller-Eddy model developed for initially laminar wakes is not adapted to initially turbulent wakes; on the other hand, comparison with supersonic wake of the same nature seems to confirm this conclusion. The lack of detailed experimental data in this field is outlined, together with the need of a refined theoretical approach to the coherent structures existing in such flows. 相似文献
36.
In recent years, many chemical reactions have been studied by means of the quasiclassical trajectory (QCT) method within the Gaussian binning (GB) procedure. The latter consists of "quantizing" the final vibrational actions in Bohr spirit by putting strong emphasis on the trajectories reaching the products with vibrational actions close to integer values. A major drawback of this procedure is that if N is the number of product vibrational modes, the amount of trajectories necessary to converge the calculations is ~10(N)×larger than with the standard QCT method. Applying it to polyatomic processes is thus problematic. In a recent paper, however, Czako? and Bowman propose to quantize the total vibrational energy instead of the vibrational actions [G. Czako? and J. M. Bowman, J. Chem. Phys. 131, 244302 (2009)], a procedure called 1GB here. The calculations are then only ~10 times more time consuming than with the standard QCT method, allowing thereby for considerable numerical saving. In this paper, we propose some theoretical arguments supporting the 1GB procedure and check its validity on model test cases as well as the prototype four-atom reaction OH+D(2)→HOD+D. 相似文献
37.
38.
A visual study is performed in a supersonic, two-dimensional wake; the high value of the Reynolds number ensures that the wake is turbulent from the trailing edge. The flow is seeded by fluid vaporization in one boundary layer upstream of the trailing edge; a light sheet is generated by a Q-switched, high energy ruby laser. The set of photographs taken from the trailing edge up to the far wake is then processed after digitization of the pictures. A progressive contamination of the lower part of the wake by the fluid initially present in the upper part can be observed. In the far wake region, well organized large scale structures can be visualized. Statistics are performed and the results are compared with previous hot-wire measurements and discussed in terms of downstream wake behaviour.This paper was presented at the 9th Symposium on turbulence, University of Missouri-Rolla, October 1–3, 1984 相似文献
39.
40.
Marc Bonnet 《Comptes Rendus Mecanique》2010,338(7-8):377-389
This article is concerned with establishing the topological sensitivity (TS) against the nucleation of small trial inclusions of an energy-like cost function. The latter measures the discrepancy between two time-harmonic elastodynamic states (respectively defined, for cases where overdetermined boundary data is available for identification purposes, in terms of Dirichlet or Neumann boundary data for the same reference solid) as the strain energy of their difference. Such cost function constitutes a particular form of error in constitutive relation and may be used for e.g. defect identification. The TS is expressed in terms of four elastodynamic fields, namely the free and adjoint solutions for Dirichlet or Neumann data. A similar result is also given for the linear acoustic scalar case. A synthetic numerical example where the TS result is used for the qualitative identification of an inclusion is presented for a simple 2D acoustic configuration. 相似文献