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101.
Vu P Bui 《Tetrahedron》2004,60(3):641-646
Several chiral hydroxylated polymers have been prepared, via ADMET techniques, from the diene diol derived from bromobenzene, obtained by means of whole-cell fermentation with Escherichia coli (JM109 pDTG601). 相似文献
102.
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105.
F.L. Fabbri P. Picozza L. Satta J. Berger J. Duflo L. Goldzahl J. Oostens F. Plouin M. Van Den Bossche L.Vu Hai G. Basini G. Bizard C. Le Brun 《Nuclear Physics A》1980,338(2):429-435
Evidence for an enhancement in the isospin system at M = 1130 MeV/c2 (Γ = 80 MeV/c2) has been found in the reaction αp → αx at an incident α-momentum of 4.00 and 5.08 GeV/c. A strong t-dependence of the cross section and a mass-slope correlation are seen as the main features of the data. 相似文献
106.
There are many studies on the asymptotic behavior of solutions of differential equations. In the present paper, we consider another aspect of this problem, namely, the rate of the asymptotic convergence of solutions. Let ϕ (t) be a scalar continuous monotonically increasing positive function tending to ∞ as t → ∞. It is established that if all solutions of a differential system satisfy the inequality
then the solution x(t; t
0, x
0) of this differential system tends to 0 faster than
.__________Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 57, No. 1, pp. 137–142, January, 2005. 相似文献
107.
The stability constants of 2, 2-bis-hydroxymethyl-propionates of rare earths have been determined at ionic strength 0,100 (NaClO4) at 25.0°C by a potentiometric method. The ligand forms 1 : 1 and 1 : 2 complexes with all the rare earths and weak 1 : 3 complexes with light rare earths only. In these last complexes, it binds in a unidentate way. The dissociation constant of the acid has also been measured. 相似文献
108.
109.
Moiz Ahmad Yinan Liu Zachary W. Slavens Russell Low Elmar Merkle Ken-Pin Hwang Anthony Vu Jingfei Ma 《Magnetic resonance imaging》2010
Sampling water and fat signals symmetrically (i.e., at 0° and 180° relative phase angles) in a dual-echo Dixon technique offers high intrinsic tolerance to phase fluctuations in postprocessing and maximum signal-to-noise performance for the separated water and fat images. However, identification of which image is water and which image is fat after their separation is not possible based on the phase information alone. In this work, we proposed a semiempirical automatic image identification method that is based on the intrinsic asymmetry between the water and fat chemical shift spectra. Specifically, the approximately bimodal feature of the fat spectra and the observation that most in vivo tissues are either predominantly water or predominantly fat are used to construct a spectrum-based algorithm. Additional refinement is accomplished by considering the spatial distribution of the tissues that may have a coexistence of water and fat. The final improved algorithm was tested on a total of 131 three-dimensional patient datasets collected from different scanners and found to yield correct water and fat identification in all datasets. 相似文献
110.
We present a theory of ultradistributional boundary values for harmonic functions defined on the Euclidean unit ball. We also give a characterization of ultradifferentiable functions and ultradistributions on the sphere in terms of their spherical harmonic expansions. To this end, we obtain explicit estimates for partial derivatives of spherical harmonics, which are of independent interest and refine earlier estimates by Calderón and Zygmund. We apply our results to characterize the support of ultradistributions on the sphere via Abel summability of their spherical harmonic expansions. 相似文献