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61.
Xie F Li D Tyree L Li L Sovkov VB Ivanov VS Magnier S Marjatta Lyyra A 《The Journal of chemical physics》2008,128(20):204313
The Cs(2) 2 (3)Delta(1g) and b (3)Pi(0u) states have been observed by infrared-infrared double resonance spectroscopy for the first time. 221 2 (3)Delta(1g)<--A (1)Sigma(u) (+)<--X (1)Sigma(g) (+) double resonance lines have been assigned to transitions into the 2 (3)Delta(1g) v=6-13 vibrational levels. Resolved fluorescence into the b (3)Pi(0u) v(')=0-48 levels has been recorded. Molecular constants and potential energy curves are determined by the global fit of the entire set of the experimental data. Theoretical potential energy curves of the 2 (3)Delta(g) and b (3)Pi(u) states have been determined in the framework of the pseudopotential method and are compared with the experimental results. 相似文献
62.
A new blue emitting 2‐allyl‐6‐(2‐dimethylaminoethyloxy)‐benzo[de]isoquinoline‐1,3‐dione, bearing an allylic group has been designed and synthesized. Bulk radical copolymerization has been carried out in order to prepare a fluorescent copolymer, based on styrene. The main photophysical characteristics of the monomeric and polymeric fluorophores have been investigated both in the absence and presence of metal cations and protons. It has been found that the monomeric naphthalimide can be used as a sensor for protons and Zn2+, Ni2+, Ce3+, Cu2+, Co2+, Ag+ cations. The polymeric fluorophore has been shown to be a selective chemosensor for Cu2+ cations. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
63.
Madhura Marathe Jérôme Lagoute Vincent Repain Sylvie Rousset Shobhana Narasimhan 《Surface science》2012,606(11-12):950-955
We have studied electronic structure of Fe-deposited Au(111) by performing ab initio density functional theory calculations. We find that the magnetic moment on the deposited Fe layer is enhanced as compared to that in bulk iron. We observe a large number of new states on the Fe-deposited surface — one of which is in the majority spin channel having similar dispersion to that on the clean surface, and others in the minority spin channel. The effective mass of electrons in surface states near the Fermi level increases on Fe deposition. The electronic properties are found to be insensitive to the stacking of near-surface layers. We need to use very thick slabs in our calculations to avoid splitting of surface states due to spurious interactions between the two surfaces of the slab. Using the local density of states profiles for different surface states, we conclude that in scanning tunneling microscope experiments one can detect two of the surface states — one in the majority channel below the Fermi level, and another in the minority channel appearing just above the Fermi energy. We compare our results to those from scanning tunneling spectroscopy experiments. 相似文献
64.
Florine Cavelier Sylvie Gomez Robert Jacquier Muriel Llinares Jean-Luc Mercadier Clment Petrus Jean Verducci 《Tetrahedron: Asymmetry》1993,4(12)
This work describes a convenient and accurate method for optical purity determination of α-hydroxy acids. Their derivatization with commercially available valine methyl ester affords diastereoisomers easily separable by HPLC using achiral C18 columns. 相似文献
65.
Makhlouf Amoura Cécile Roux Sylvie Masse Nathalie Steunou Thibaud Coradin 《Comptes Rendus Chimie》2010,13(1-2):52-57
Zirconium oxyhydroxide nanoparticles prepared by an aqueous route were evaluated for Escherichia coli bacteria encapsulation. A low viability rate was measured 24 hours after immobilization that could be attributed to nanoparticle cytotoxicity. Moreover, the presence of glycerol, a long-term cell-preserving molecule, hindered gel formation, probably due to its adsorption on the nanoparticle surface. A comparison with boehmite and ferrihydrite gels previously synthesized following a similar aqueous colloidal route suggests that the generalization of this method will rely on a careful control of the nanoparticle surface reactivity and may require surface chemical modification. 相似文献
66.
67.
Sylvie Guerre 《Israel Journal of Mathematics》1986,53(2):191-208
We prove that every normalized sequence inL
p
, weakly null ifp>2 and equivalent to the unit vector basis ofl
2 if 1≦p<2, has for allε>0 a subsequence which is 2(1+ε)-symmetric. This result was known forp=1 (H.P. Rosenthal) andp∈N (W.B. Johnson, B. Maurey, G. Shechtman, L. Tzafriri). Here, we use the techniques of stability which were introduced by
J.L. Krivine and B. Maurey: as well as providing new results, this approach unifies and simplifies previous known results.
相似文献
68.
The preparation of silicated hydroxyapatite Ca10(PO4)6−x(SiO4)x(OH)2−x (SiHA) with 0?x?2 was investigated using a wet precipitation method followed by a heat treatment. X-ray diffraction and Rietveld refinement, Fourier transformed IR (FTIR) spectroscopy, elemental analyses, transmission electron microscopy and thermal analyses were used to characterize the samples. The raw materials were composed of a partially silicated and carbonated apatite and a secondary minor phase containing the excess silicon. Single phase silicated hydroxyapatites, with 0?x?1, could be synthesized after a thermal treatment of the raw powders above 700 °C. The presence of carbonate groups in the raw apatite played an important role in the incorporation of silicates during heating. From the different results, the mechanisms of formation of SiHA are discussed. 相似文献
69.
Summary. In this paper, we study finite volume schemes for the nonhomogeneous scalar conservation law with initial condition . The source term may be either stiff or nonstiff. In both cases, we prove error estimates between the approximate solution given by a finite volume scheme (the scheme is totally explicit in the nonstiff case, semi-implicit in the stiff case) and the entropy solution. The order of these estimates is in space-time -norm (h denotes the size of the mesh). Furthermore, the error estimate does not depend on the stiffness of the source term in the stiff case. Received October 21, 1999 / Published online February 5, 2001 相似文献
70.
Characterization of Linear Structures 总被引:2,自引:0,他引:2
Sylvie Dubuc 《Designs, Codes and Cryptography》2001,22(1):33-45
We study the notionof linear structure of a function defined from Fmto Fn, and in particular of a Boolean function.We characterize the existence of linear structures by means ofthe Fourier transform of the function. For Boolean functions,this characterization can be stated in a simpler way. Finally,we give some constructions of resilient Boolean functions whichhave no linear structure. 相似文献