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131.
132.
Mijovilovich A Hamman S Thomas F de Groot FM Weckhuysen BM 《Physical chemistry chemical physics : PCCP》2011,13(13):5600-5604
X-ray Emission Spectroscopy (XES) crossover peaks were shown to be sensitive to the protonation state of solvent molecules in the Zn protein carbonic anhydrase and its model compounds. Here we extend such studies to galactose oxidase models i.e. Cu(ii) open d-shell systems, illustrating that XES combined with FEFF8 simulations reflect changes in the protonation state of the phenolate ligand for the copper center. 相似文献
133.
The essential oil (EO) of M. aquatica L. growing wild in Corsica was isolated by dry vapor distillation and submitted to combined analysis by column chromatography over silica gel, GC(RI), GC-MS and 13C NMR spectroscopy. The composition was dominated byoxygenated monoterpenes and characterized by the occurrence of menthofuran (50.7%) as the major component. In parallel, seven laboratory-distilled oil samples isolated from individual plants collected in Corsica were analyzed by GC(RI) and 13C NMR spectroscopy. Onlyquantitative differences were observed between the samples. Beside the usual terpenes, various p-menthane lactones (mintlactone, isomintlactone, hydroxymintlactone, menthofurolactone and epimenthofurolactone) have been identified in all the oil samples. 相似文献
134.
135.
We show that the complexity of a parabolic or conic spline approximating a sufficiently smooth curve with non-vanishing curvature
to within Hausdorff distance ɛ is c
1ɛ−1/4 + O(1), if the spline consists of parabolic arcs, and c
2ɛ−1/5 + O(1), if it is composed of general conic arcs of varying type. The constants c
1 and c
2 are expressed in the Euclidean and affine curvature of the curve. We also show that the Hausdorff distance between a curve
and an optimal conic arc tangent at its endpoints is increasing with its arc length, provided the affine curvature along the
arc is monotone. This property yields a simple bisection algorithm for the computation of an optimal parabolic or conic spline.
The research of SG and GV was partially supported by grant 6413 of the European Commission to the IST-2002 FET-Open project
Algorithms for Complex Shapes in the Sixth Framework Program. 相似文献
136.
Sylvain Damour 《manuscripta mathematica》2002,109(2):203-222
Let f : M → M′ be a smooth CR mapping between a generic real analytic submanifold M ⊂ ℂ
n
, n > 1, and a real analytic subset M′ ⊂ ℂ
n′
. We prove that if M is minimal and if M′ does not contain any complex curves, then f is analytic on a dense open subset of M. More generally, we establish an upper estimate of the partial analyticity of f, which depends on the maximal dimension of local holomorphic foliations contained in M
′
.
Received: 7 August 2001
Mathematics Subject Classification (2000): 32V25, 32V40, 32H99 相似文献
137.
Sylvain Rodriguez Jean-Luc Wolfender Kurt Hostettmann Gendaramyn Odontuya Ondognii Purev 《Helvetica chimica acta》1996,79(2):363-370
Chemical screening of the secondary metabolites from Halenia corniculata L. (CORNAZ ), by LC/UV,LC/TSP-MS (thermospray), and LC/ES-MS (electrospray) was used for the targeted isolation of corniculoside ( 1 ), a new biosidic ester secoiridoid. The structure was established as 7-β-[(E)-4′-O-(β-D -glucopyranosyl)caffeoyloxy]-sweroside by 1D- and 2D-NMR, LC/UV, LC/MS, and FAB-MS data, in combination with chemical reactions. 相似文献
138.
Mourre’s commutator theory is a powerful tool to study the continuous spectrum of self-adjoint operators and to develop scattering
theory. We propose a new approach of its main result, namely the derivation of the limiting absorption principle (LAP) from
a so called Mourre estimate. We provide a new interpretation of this result.
Received: September 20, 2006. Revised: February 1, 2007. 相似文献
139.
Sylvain Sorin 《International Journal of Game Theory》1998,27(3):315-330
Given an information structure a function that measures how the inferences made by the agents spread among the states is
defined; it specifies for each event its impact at each state, for each agent. Several properties are established.
Received November 1994/Revised version September 1996 相似文献
140.