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151.
Claude Delmas Francis Menil Gilles Le Flem Claude Fouassier Paul Hagenmuller 《Journal of Physics and Chemistry of Solids》1978,39(1):51-53
A Mössbauer study of the dimensionality of magnetic interactions in the layer oxide LiCr0.99Fe0.01O2 shows a 2-D behaviour. 相似文献
152.
Guy Solladié Christine Greck Gilles Demailly Arlette Solladié-Cavallo 《Tetrahedron letters》1982,23(48):5047-5050
It is shown that reductions of β-ketosulfoxides of identical chirality (R) at sulfur, lead to reduction products of opposite stereochemistry according to the reducing agent used. The high enantiomeric excesses obtained (80 to 100%) provide a general route to both enantiomers of methylcarbinols from the corresponding esters. 相似文献
153.
Gilles Pisier 《Acta Mathematica》1983,151(1):181-208
154.
Gilles Godefroy 《Israel Journal of Mathematics》1983,44(1):61-74
We show that ifE is a non-reflexive Banach lattice, there exists for everyn a dual of finite even order ofE which contins isometicallyl
n
/l
. We show that itE is a Banach lattice which is isometric to the dual of a Banach spaceX, then the order intervals are σ (E, X)-compact. We prove then that under various conditions, a Banach lattice which is a dual as a Banach space, is a dual as a
Banach lattice. In particular, this is true when the predual ofE is unique.
相似文献
155.
Jean-Louis Tassoul Gilles Aubin 《Journal of Mathematical Analysis and Applications》1974,45(1):116-126
This paper deals with finite-amplitude axisymmetric disturbances in a self-gravitating fluid column of finite radius R. It is shown that the cutoff wavelength λnl above which gravitational breakup occurs now depends on the relative amplitude of the initial perturbation. Actually, for small-but finite-amplitude disturbances, , where λl ( = 5.8898R) designates the cutoff wavelength predicted in the linear approximation. 相似文献
156.
The perturbation of the racemic equilibrium of luminescent D3 lanthanide(III) complexes by added chiral agents, such as amino acids, may be a useful technique for determining the absolute configuration of the added species. It is shown in this work, however, that simple interpretation of the equilibrium shift of racemic tris-terdentate complexes of Tb(III) with 2,6-pyridine-dicarboxylate by amino acids, as measured by the sign of the resultant circularly polarized luminescence (CPL) in terms of specific structural characteristics is not possible. CPL results for a number of derivatized amino acids are also presented, and some insights into the nature of the chiral discriminatory forces that might be exploited in this kind of study are discussed. 相似文献
157.
F.?HuEmail author W.?Fa J.?Dong 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,46(3):331-334
The quantum conductance oscillations (QCOs) of the intramolecular junction
(IMJ) composed of two single-wall carbon nanotubes (SWNTs) have been studied
by using a π-orbital only tight-binding (TB) model and a Green’s
function technique. It is found that in the IMJs in addition to the rapid
QCO frequencies corresponding to the constituent tubes there exist also
their sum frequencies. The slow QCO frequencies of the IMJ will be different
from those of its corresponding two perfect tubes if they have different
chiral angles. 相似文献
158.
Laras Y Quéléver G Garino C Pietrancosta N Sheha M Bihel F Wolfe MS Kraus JL 《Organic & biomolecular chemistry》2005,3(4):612-618
Inhibition of gamma-secretase, one of the enzymes responsible for the cleavage of the amyloid precursor protein (APP) to produce pathogenic A beta peptides, is an attractive approach for the treatment of Alzheimer's disease. We have designed a new gamma-secretase thiazolamide inhibitor bearing a dihydronicotinoyl moiety as Redox Delivery System which allows specific delivery of the drug to the brain. Through, on the one hand, A beta peptide production measurements by specific in vitro assays (gamma-secretase Cell Free assay and Cell Based assay on HEK 293 APP transfected cells) and, on the other hand, pharmacokinetic studies on animal models, the new inhibitor shows a good pharmacokinetic profile as well as a potent gamma-secretase inhibitory activity in vitro. From the obtained results, it is expected that drug will be mainly delivered to the CNS with low diffusion in the peripheral tissues. Consequently the side effects of this gamma-secretase inhibitor on the immune cells could be reduced. 相似文献
159.
Phase-sensitive optical low-coherence reflectometry technique applied to the characterization of photonic crystal fiber properties 总被引:3,自引:0,他引:3
Palavicini C Jaouën Y Debarge G Kerrinckx E Quiquempois Y Douay M Lepers C Obaton AF Melin G 《Optics letters》2005,30(4):361-363
Localized measurements of group-velocity dispersion and birefringence of photonic crystal fibers are achieved with a phase-sensitive optical low-coherence reflectometry technique. This technique is efficient for fiber samples no longer than 1 m. Theoretical simulations are in good agreement with experimental results. As a result, the stress-induced birefringence proves to be at most 1 order of magnitude below the geometrical-shape birefringence. 相似文献
160.
We carried out a numerical study of the second mode transition in finite-sized, microstructured optical fibers (MOFs) for several values of the matrix refractive index. We determined a unique critical geometrical parameter for the second mode cutoff that is valid for all the matrix refractive indices studied. Finite size effects and extrapolated results for infinite structures are described. Using scaling laws, we provide a generalized phase diagram for solid-core MOFs that is valid for all refractive indices, including those of the promising chalcogenide MOFs. 相似文献