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221.
Fadi Khaddour Auriane Knorst-Fouran Frédéric Plantier Manuel M. Piñeiro Bruno Mendiboure Christelle Miqueu 《Adsorption》2014,20(4):649-656
The adsorption of pure methane in activated carbon Ecosorb was studied by combining grand canonical ensemble Monte Carlo molecular simulations and an experimental approach based on a gravimetric device. Experimental and calculated adsorption isotherms of methane were determined in supercritical conditions at 303.15 and 353.15 K and pressures up to 10 MPa. The comparison between both experimental and estimated data proves the consistency of the methodology used in this work, starting from the characterization of the porous media in terms of pore size distribution, the determination of the experimental adsorption isotherms, and the final estimation of computational results through estimated isotherms determination. Moreover, additional differential enthalpy of adsorption calculations were compared with experimental values obtained by means of a manometric/calorimetric technique. The good agreement shows the strength and the originality of this paper by combining experimental and computational homemade results allowing a complete characterization of the activated carbon substrate and its methane storage capacity. 相似文献
222.
Jihen Mahfoudh Slim Salhi Aurélie Auguste Christelle Delaite Rachid El Gharbi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):280-285
A series of random polyesteramides (PEAs) within a range of molar composition from 90/10 to 10/90 were synthesized by a direct melt polycondensation of glycolic acid and β-alanine. Their structures were fully characterized by NMR spectroscopy. The resulting copolymers are amorphous and present increasing glass transition temperatures at increasing β-alanine contents. The copolymers were also characterized by, FTIR, TGA and viscosimetry measurements. 相似文献
223.
224.
Olivier Alévêque Pierre-Yves Blanchard Christelle Gautier Marylène Dias Tony Breton Eric Levillain 《Electrochemistry communications》2010,12(11):1462-1466
The Laviron's interaction model, dedicated to randomly distributed electroactive adsorbed species, was extended to a non-random distribution in order to extract the current–voltage characteristics from any surface distribution of electroactive centers on self-assembled monolayer (SAM). Confronted to electrochemical behaviour of nitroxyl radical SAMs, the agreement observed between theory and experiments provides evidence of a distribution independence of the interaction parameters. 相似文献
225.
226.
Christelle Lamazzi Armelle Dreau Christine Flouzat Rob ter Halle 《Tetrahedron letters》2009,50(31):4502-4505
The Letter describes the investigation of an industrial reaction of N-methylphenylpiperazine and chloronicotinonitrile, under microwave heating. Besides the formation of the expected 2-(4-methyl-2-phenylpiperazinyl)pyridine-3-carbonitrile (4), extension of the scale leads to unexpected by-products. A specific pathway due to the formation of a reactive ‘ionic alkylating intermediate’ formed in situ under microwave conditions is proposed to explain the results observed. 相似文献
227.
Paul V. Fish Malcolm Mackenny Gerwyn Bish Timothy Buxton Russell Cave David Drouard David Hoople Alan Jessiman Duncan Miller Christelle Pasquinet Bhairavi Patel Keith Reeves Thomas Ryckmans Melanie Skerten Florian Wakenhut 《Tetrahedron letters》2009,50(4):389-2768
The (R)- and (S)-N-Boc-morpholine-2-carboxylic acids 9 and 10 were prepared using an enantioselective synthesis employing a highly selective enzyme-catalyzed kinetic resolution of racemic n-butyl 4-benzylmorpholine-2-carboxylate (11) as the key step. Acids 9 and 10 were then converted efficiently and stereoselectively to reboxetine analogs 3 and 4. 相似文献
228.
Anna R. Lomasney Christelle Guillo Ashley M. Sidebottom Michael G. Roper 《Analytical and bioanalytical chemistry》2009,394(1):313-319
The capillary electrophoresis (CE) conditions for a competitive immunoassay of glucagon were optimized for highest sensitivity
of the immunoassay and resolution of the electrophoretic peaks using a Box–Behnken design. Injection time, voltage ramp time,
and separation voltage were varied between three levels and two responses, bound-to-free (B/F) ratio of the immunoassay peaks and resolution between the peaks, were measured. Analysis of variance was applied to fit
a predictive model, and a desirability function was used to simultaneously optimize both responses. A 10-s injection, 1.6-min
ramp time, and a 22-kV separation voltage were the conditions found when high B/F was given more emphasis than high resolution. To test the model, calibration curves of a glucagon immunoassay were measured
at the optimum and least optimum CE conditions. Optimal conditions increased the sensitivity of the immunoassay by 388% compared
to the least optimum conditions while maintaining adequate resolution.
相似文献
Michael G. RoperEmail: |
229.
Christelle Navone Jean-Pierre Pereira-Ramos Rita Baddour-Hadjean Raphael Salot 《Ionics》2010,16(7):577-580
We report for the first time the use of lithiated crystalline V2O5 thin films as positive electrode in all-solid-state microbatteries. Crystalline LixV2O5 films (x ≈ 0.8 and 1.5) are obtained by vacuum evaporation of metallic lithium deposited on sputtered c-V2O5. An all-solid-state lithium microbattery of Li1.5V2O5/LiPON/Li exhibited a typical reversible capacity of 50 μAh/cm2 in the potential range 3.8/2.15 V which exceeds by far the results known on all-solid-state lithium batteries using amorphous
V2O5 films and lithiated amorphous LixV2O5 thin films as positive electrode. Hence, the present work opens the possibility of using high performance crystalline lithiated
V2O5 thin films in rocking-chair solid-state microbatteries. 相似文献
230.
Warren R Hayes C Pointon L Hoff R Gilbert FJ Padhani AR Rubin C Kaplan G Raza K Wilkinson L Hall-Craggs M Kessar P Rankin S Dixon AK Walsh J Turnbull L Britton P Sinnatamby R Easton D Thompson D Lakhani SR Leach MO;UK MRC study of MRI screening for breast cancer in women at high risk 《Magnetic resonance imaging》2006,24(7):917-929
OBJECTIVES: The aim of this study was to assess the consistency and performance of radiologists interpreting breast magnetic resonance imaging (MRI) examinations. MATERIALS AND METHODS: Two test sets of eight cases comprising cancers, benign disease, technical problems and parenchymal enhancement were prepared from two manufacturers' equipment (X and Y) and reported by 15 radiologists using the recording form and scoring system of the UK MRI breast screening study [(MAgnetic Resonance Imaging in Breast Screening (MARIBS)]. Variations in assessments of morphology, kinetic scores and diagnosis were measured by assessing intraobserver and interobserver variability and agreement. The sensitivity and specificity of reporting performances was determined using receiver operating characteristic (ROC) curve analysis. RESULTS: Intraobserver variation was seen in 13 (27.7%) of 47 of the radiologists' conclusions (four technical and seven pathological differences). Substantial interobserver variation was observed in the scores recorded for morphology, pattern of enhancement, quantification of enhancement and washout pattern. The overall sensitivity of breast MRI was high [88.6%, 95% confidence interval (CI) 77.4-94.7%], combined with a specificity of 69.2% (95% CI 60.5-76.7%). The sensitivities were similar for the two test sets (P=.3), but the specificity was significantly higher for the Manufacturer X dataset (P<.001). ROC curve analysis gave an area under the curve of 0.85 (95% CI 0.79-0.92) CONCLUSIONS: Substantial variation in all elements of the scoring system and in the overall diagnostic conclusions was observed between radiologists participating in MARIBS. High overall sensitivity was achieved with moderate specificity. Manufacturer-related differences in specificities possibly occurred because the numerical thresholds set for the scoring system were not optimised for both equipment manufacturers. Scoring systems developed on one equipment software may not be transferable to other manufacturers. 相似文献