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41.
This article describes how Semantic Web technologies can be used to interlink musical data sources that have traditionally been isolated and difficult to integrate. 相似文献
42.
Bertet P Auffeves A Maioli P Osnaghi S Meunier T Brune M Raimond JM Haroche S 《Physical review letters》2002,89(20):200402
We have measured the complete Wigner function W of the vacuum and of a single-photon state for a field stored in a high-Q cavity. This experiment implements the direct Lutterbach and Davidovich method [L. G. Lutterbach and L. Davidovich, Phys. Rev. Lett. 78, 2547 (1997)]] and is based on the dispersive interaction of a single circular Rydberg atom with the cavity field. The nonclassical nature of the single-photon field is exhibited by a region of negative W values. Extensions to other nonclassical cavity field states are discussed. 相似文献
43.
Lippens G Chessari G Wieruszeski JM 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,156(2):242-248
Despite the use of high resolution magic angle spinning NMR, the NMR linewidth of anchored molecules on the commonly used Merrifield solid phase resins remains larger than that of the corresponding molecules in solution. We investigate the different mechanisms that might be at the origin of this line broadening. Experimentally, we use the CPMG method to determine the (15)N relaxation times of a tethered tripeptide and show that the slow resin dynamics significantly contributes to the transverse relaxation. 相似文献
44.
45.
François Treussart Nicolas Dubreuil Jongthan Cave Knight Vahid Sandoghdar Jean Hare Valçrie Lefçvre-Seguin Jean-Michel Raimond Serge Haroche 《电信纪事》1997,52(11-12):557-568
Light can be confined efficiently in the high-Q, small-volume whispering-gallery-modes observed in silica microspheres. By coupling these microspheres to eroded optical fibers and fiber tips, direct mapping of the whispering-gallery modes has been achieved and the mode numbers have been assessed. The properties of these modes have allowed us to obtain laser action with very low thresholds in Nd-doped silica microspheres. Further projects in the field of non-linear optics and cavity quantum electrodynamics are described. 相似文献
46.
47.
Bouchoul Nassim Fourré Elodie Tatibouët Jean-Michel Batiot-Dupeyrat Catherine 《Plasma Chemistry and Plasma Processing》2019,39(3):713-727
Plasma Chemistry and Plasma Processing - The coupling of catalyst and nonthermal plasma for the dry reforming of methane was investigated with a special attention to the textural and structural... 相似文献
48.
Our efforts in construction the 1,2-dioxane ring of plakortolides through two approaches are described. The first one involved as a key step an acid catalyzed 6-endo ring closure of β-hydroperoxy trans-epoxides directed by a vinyl group adjacent to the epoxide function. By this route, an advanced intermediate of plakortolides was obtained in six steps and 35% overall yield. The second approach featured a 1,2-dioxane ring forming by a double opening of bis-epoxides by ethereal hydrogen peroxide. This reaction did not proceed in the expected sense and exclusive formation of hydroperoxy tetrahydropyran derivatives was observed via a tandem oxacyclization–hydroperoxidation sequence. 相似文献
49.
Jean-Michel NavarreDominique Guianvarc'h Audrey Farese-Di GiorgioRoger Condom Rachid Benhida 《Tetrahedron letters》2003,44(10):2199-2202
A short route to novel α-(2-aminothiazolyl)-C-nucleosides has been developed. The key step was the high diastereoselective reduction of the hemiacetal intermediates using L-Selectride, which afforded the corresponding R-diols in quantitative yields. These diols were converted, after C4-C1 ring closure and protecting groups cleavage, to their corresponding free α-C-nucleosides. 相似文献
50.
The structure and absolute configuration of natural 8-epi-9-deoxygoniopypyrone have been confirmed by an efficient and highly diastereoselective synthesis in 15 steps from (S)-mandelic acid with an overall yield of 43%. 相似文献