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61.
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
62.
The biochemical composition of leaves from Coffea pseudozanguebariae, a wild caffeine-free coffee species, was determined. Two phenolic compounds were extracted from leaves, separated and characterized. Their structures were elucidated by mass spectrometry, and 1D and 2D NMR spectroscopy and were shown to be mangiferin (1) and isomangiferin (2), which were the main polyphenol products. Multiphoton fluorescence imaging was performed to visualize polyphenol distribution in leaf cross sections. Consistent biochemical analysis cell imaging techniques on leaves revealed yellow fluorescence in the epidermis and parenchyma cells corresponding to xanthone compounds. 相似文献
63.
Thomas Mouton Xavier Mercier Maxime Wartel Nathalie Lamoureux Pascale Desgroux 《Applied physics. B, Lasers and optics》2013,112(3):369-379
This paper presents the study we carried out on the formation of soot particles in low-pressure premixed CH4/O2/N2 flames by using Laser-Induced Incandescence (LII). Flames were stabilised at 26.6 kPa (200 torr). Four different equivalence ratios were tested (Φ = 1.95, 205, 2.15 and 2.32), Φ = 1.95 corresponding to the equivalence ratio for which LII signals begin to be measurable along the flame. The evolution of the LII signals with laser fluence (fluence curve), time (temporal decay) and emission wavelength is reported at different heights above the burner. We specifically took advantage of the low-pressure conditions to probe with a good spatial resolution the soot inception zone of the flames. Significant different behaviours of the fluence curves are observed according to the probed region of the flames and Φ. In addition, while the surface growth process is accompanied by an increase in the LII decay-times (indicator of the primary particle diameter) at higher Φ, decay-times become increasingly short at lower Φ reaching a constant value along the flame at Φ = 1.95. These behaviours are consistent with the detection of the smallest incandescent particles in the investigated flames, these particles having experienced very weak surface growth. Flame modelling including soot formation has been implemented in flames Φ = 2.05 and 2.32. Experimental quantitative soot volume fraction profiles were satisfactorily reproduced by adjusting the fraction of reactive soot surface available for reactions. The qualitative variation of the computed soot particle diameter and the relative weight of surface growth versus nucleation were consistent with the experimental observations. 相似文献
64.
E. De Pascale L. De Pascale 《Proceedings of the American Mathematical Society》2002,130(11):3249-3254
The use of K-normed spaces gives us the possibility to prove that a fixed point theorem due to B. Luo is equivalent to the Banach Contraction Principle. This confirms the conspiracy among fixed point theorems. Moreover the theorem of Lou is improved and extended to different contexts. A counterexample about the fixed points of the sum of a contraction and an integral operator is given. The usefulness of K-norm is tested on a Volterra integral equation as well.
65.
Laser-induced autofluorescences show a strong intensity distortion for endogenous NADH in the UV and synthesized markers in the NIR range because of tissue optics. Rescaling taking into account bio-optical methods results in the chromophore profile in the observed tissue region. For the in vivo tests an experimental NIR imager was used. NIR fluorescence of the entire body of small animals can be imaged. For first experiments an undifferentiated superficial tumor of mouse thigh was used. Corrections that are due to tissue optics must take care of a more strongly scattering of the light in the NIR range in comparison to the UV fluorescence such as in optical biopsy. For example, the diameter of the fluorescent volume is apparently larger for the same reason. Therefore, the established rescaling from the UV adapted to the NIR range is important for the interpretation fluorescence pictures in biomedicine. 相似文献
66.
Building on the method of Kantorovich majorants, we give convergence results and error estimates for the two-step Newton method for the approximate solution of a nonlinear operator equation. 相似文献
67.
Martin Me Court Eric Imbert Pascale Vincensini-fort Jérôme Mars Hervé Ribot Dominique Persegol Thierry Jacquemin Josette Toussan-berger Denis Trystram José Camargo da Costa Mahmoud Helal Atman Guerchaoui Noureddine Mhaya Ignacio Jesus Ania de Briseno Chien Nguyen Duc Laurent Chety 《电信纪事》1989,44(3-4):194-197
68.
Javier Ulises Ortiz MayoMartial Thomas Carole SaintoméPascale Clivio 《Tetrahedron》2003,59(37):7377-7383
The synthesis of a building block containing the photobiologically relevant cis-syn thymine cyclobutane photoproduct and its incorporation into oligonucleotides by the phosphoramidite-based solid-phase synthesis is reported. Compared to previous syntheses, this route is extremely short and allows such modified oligonucleotides to be easily available for biological studies. 相似文献
69.
The transposition of the molecular ions (ring contraction) of 2-decalones is demonstrated by a study of the [M–28]+˙ peak and its homologue in labelled products using ionization and appearance energy measurements, and mass analysed ion kinetic energy and collision induced dissociation spectra. 相似文献
70.
Pascale Tavarès Marek M. Kubicki Philippe Meunier Bernard Gautheron Gabriel Dousse Hélène Lavayssière Jacques Satgé 《Transition Metal Chemistry》1992,17(3):220-223
o-Thiatelluraphenylenezirconocene complexes were obtained in good yield by reaction of dilithiumo-benzenthiatelluride with zirconocene dichlorides. These compounds represent the first examples of heterodichalcogenaphenylene
bent metallocences. They were characterized by spectroscopic methods and the effect on the n.m.r. results of stepwise substitution
of one and two Te atoms for S is discussed.
X-ray crystal structure analysis was performed for one representative complex. The structure is very similar to that previously
reported for a diselenaphenylene complex, but the disorder observed for chalcogen atoms prevents an accurate comparison of
the geometrical parameters with other related compounds. 相似文献