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排序方式: 共有402条查询结果,搜索用时 15 毫秒
31.
Richard D. Chambers Takashi Okazoe Emmanuelle Thomas 《Journal of fluorine chemistry》2010,131(9):933-936
Reactions of dialkyl ethers with either fluorine or Selectfluor™ led to the formation of unusual difluorinated polyether products in modest yields. A mechanism involving initial fluorination of the site adjacent to ether oxygen followed by elimination of hydrogen fluoride, reaction of the generated enol system with a further equivalent of fluorinating agent giving an oxonium system which reacts with water during aqueous work-up to lead eventually to the products observed, is suggested. 相似文献
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Cyrielle Roquelet Jean‐Sébastien Lauret Dr. Valérie Alain‐Rizzo Dr. Christophe Voisin Dr. Romain Fleurier Dr. Morgan Delarue Damien Garrot Dr. Annick Loiseau Prof. Philippe Roussignol Prof. Jacques A. Delaire Prof. Emmanuelle Deleporte Prof. 《Chemphyschem》2010,11(8):1667-1672
We report on a new, original and efficient method for π‐stacking functionalization of single‐wall carbon nanotubes. This method is applied to the synthesis of a high‐yield light‐harvesting system combining single‐wall carbon nanotubes and porphyrin molecules. We developed a micelle‐swelling technique that leads to controlled and stable complexes presenting an efficient energy transfer. We demonstrate the key role of the organic solvent in the functionalization mechanism. By swelling the micelles, the solvent helps the non‐water‐soluble porphyrins to reach the micelle core and allows a strong enhancement of the interaction between porphyrins and nanotubes. This technique opens new avenues for the functionalization of carbon nanostructures. 相似文献
36.
Alban A. Letailleur Sergey Yu Grachev Elin Søndergård Christophe Couteau Gilles Lérondel Emmanuelle Peter 《Journal of luminescence》2011,131(12):2646-2651
The application of alumina-doped ZnO (AZO) films as luminescent material for large area lighting sources has been evaluated. Thin films were grown on quartz using magnetron sputtering and subsequently annealed under argon atmosphere in a rapid thermal annealing experiment. Below 550 °C, red-shift of the optical band gap and increase of the visible emission are observed in agreement with Al diffusion and formation of interstitial oxygen atoms. At temperatures higher than 800 °C, diffusion is activated and Ostwald ripening leads to the formation of larger grains and an increase of the crystalline phase. The photoluminescence (PL) intensity is enhanced, specifically in the UV range. As a result the emission spectrum of AZO thin films can be adjusted by the annealing conditions, with equal contributions from the UV and orange parts of the PL spectrum resulting in an efficient white emission as quantified using the color space map of the Commission Internationale de l'Éclairage. 相似文献
37.
We report a pressure-dependent investigation of KMnF(3) by x-ray diffraction up to 30 GPa. The results are discussed in the framework of Landau theory and in relation to the isostructural phase transition in SrTiO(3). The phase transition temperature near 186 K in KMnF(3) shifts to room temperature at a critical pressure of P(c) = 3.4 GPa; the pressure dependence of the transition point follows ΔP(c)/ΔT(c) = 0.0315 GPa K(-1). The transition becomes second order under high pressure, close to the tricritical point. The phase transition is determined by the rotation of MnF(6) octahedra with their simultaneous expansion along the rotation axis. The rotation angle was found to increase to 10.5° at 24 GPa. An additional anomaly was observed at higher pressure around 25 GPa, suggesting a further phase transition. 相似文献
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F Blanche B Monegier D Faucher M Duchesne F Audhuy A Barbot S Bouvier G Daude H Dubois T Guillemin L Maton 《Journal of chromatography. A》2001,921(1):39-48
For cancer gene therapy, a recombinant adenovirus serotype 5 named RPR/INGN201 has been constructed by susbtitution of the E1 region with human tumor suppressor gene p53. The protein components of RPR/INGN201 virions were separated by reversed-phase HPLC and were individually identified by electrospray time-of-flight mass spectrometry and N-terminal sequencing, both on intact proteins and on their proteolytic fragments after trypsin digestion. Twenty-five peptide components of the proteome (including fiber) with greater than 0.25-0.5% contribution to the protein content of the virus were identified and characterized. Fiber was confirmed to be partially glycosylated (both the non-glycosylated and the monoglycosylated states were identified), and two proteins were isolated and identified as phosphorylation derivatives, namely protein V (non-phosphorylated and monophosphorylated) and protein IIIa (mono- and diphosphorylated). This new analytical tool proved to be very useful not only for refining our current knowledge of the polypeptide repertoire of purified infectious virions but also for monitoring and very rapidly identifying structural modifications resulting from changes in the manufacturing process. It was also used successfully for the characterization of various adenoviral constructs. 相似文献
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Florent Lafay Emmanuelle Vulliet Marie-Magdeleine Flament-Waton 《Analytical and bioanalytical chemistry》2010,396(2):937-941
A simple, rapid, sensitive, and non-consuming solvent method for the determination of cotinine in urine was developed, based
on sample preparation by the relatively new technique microextraction in packed sorbent (MEPS) and analysis by GC–MS. This
optimized method was compared with conventional solid-phase extraction/liquid–liquid extraction method used as reference.
The wide linear range (5–5,000 ng/mL) and high sensitivity of the MEPS method (limit of detection 0.8 ng/mL) allow application
to analysis of urine from smokers as well as non-smokers susceptible to passive smoking. 相似文献
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