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61.
Turdebek N. Bekjan Zeqian Chen Mathilde Perrin Zhi Yin 《Journal of Functional Analysis》2010,258(7):2483-2505
We prove that atomic decomposition for the Hardy spaces h1 and H1 is valid for noncommutative martingales. We also establish that the conditioned Hardy spaces of noncommutative martingales hp and bmo form interpolation scales with respect to both complex and real interpolations. 相似文献
62.
Carole Miossec Laurent Lanceleur Mathilde Monperrus 《Journal of separation science》2019,42(10):1853-1866
A solid‐phase extraction combined with a liquid chromatography‐tandem mass spectrometry analysis has been developed and validated for the simultaneous determination of 44 pharmaceuticals belonging to different therapeutic classes (i.e., antibiotics, anti‐inflammatories, cardiovascular agents, hormones, neuroleptics, and anxiolytics) in water samples. The sample preparation was optimized by studying target compounds retrieval after the following processes: i) water filtration, ii) solid phase extraction using Waters Oasis HLB cartridges at various pH, and iii) several evaporation techniques. The method was then validated by the analysis of spiked estuarine waters and wastewaters before and after treatment. Analytical performances were evaluated in terms of linearity, accuracy, precision, detection, and quantification limits. Recoveries of the pharmaceuticals were acceptable, instrumental detection limits varied between 0.001 and 25 pg injected and method quantification limits ranged from 0.01 to 30.3 ng/L. The precision of the method, calculated as relative standard deviation, ranged from 0.3 to 49.4%. This procedure has been successfully applied to the determination of the target analytes in estuarine waters and wastewaters. Eight of these 44 pharmaceuticals were detected in estuarine water, while 26 of them were detected in wastewater effluent. As expected, the highest values of occurrence and concentration were found in wastewater influent. 相似文献
63.
64.
Evaluation of preconcentration methods in the analysis of synthetic musks in whole‐water samples
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Joana Cavalheiro Ailette Prieto Olatz Zuloaga Hugues Preudhomme David Amouroux Mathilde Monperrus 《Journal of separation science》2015,38(13):2298-2304
According to the European Water Framework Directive, environmental assessment of organic compounds should be made in whole‐water samples, but due to their hydrophobicity and strong attraction to organic content these compounds can be found bound to suspended particle matter or in the dissolved fraction. In this work, the extraction of musk compounds was studied in whole‐water samples exhibiting different amounts of dissolved organic carbon and suspended particulate matter using polyethersulfone preconcentration technique. Matrix effects in estuarine and wastewater (both influent and effluent) were evaluated for filtered and unfiltered samples. For unfiltered samples, estuarine water exhibited matrix effects <20%, while for effluent it was up to 48% and for influent ranged from 85 to 99%. To compensate matrix effects and determine total concentrations in unfiltered samples, different quantification approaches were tested: the use of deuterated analogues and standard additions. Standard additions provided the best results for unfiltered samples. Finally, filtered and unfiltered samples were analyzed using both polyethersulfone preconcentration and membrane‐assisted solvent extraction and results showed a good agreement between the two methods. In both cases unfiltered samples provided concentrations 1.5–2.6 times higher than filtered samples. 相似文献
65.
The variability in the chemistry of cell wall polysaccharides in pericarp tissue of red-ripe tomato fruit (Solanum lycopersicon Mill.) was characterized by chemical methods and enzymatic degradations coupled to high performance anion exchange chromatography (HPAEC) and mass spectrometry analysis. Large fruited line, Levovil (LEV) carrying introgressed chromosome fragments from a cherry tomato line Cervil (CER) on chromosomes 4 (LC4), 9 (LC9), or on chromosomes 1, 2, 4 and 9 (LCX) and containing quantitative trait loci (QTLs) for texture traits, was studied. In order to differentiate cell wall polysaccharide modifications in the tomato fruit collection by multivariate analysis, chromatograms were corrected for baseline drift and shift of the component elution time using an approach derived from image analysis and mathematical morphology. The baseline was first corrected by using a "moving window" approach while the peak-matching method developed was based upon location of peaks as local maxima within a window of a definite size. The fast chromatographic data preprocessing proposed was a prerequisite for the different chemometric treatments, such as variance and principal component analysis applied herein to the analysis. Applied to the tomato collection, the combined enzymatic degradations and HPAEC analyses revealed that the firm LCX and CER genotypes showed a higher proportion of glucuronoxylans and pectic arabinan side chains while the mealy LC9 genotype demonstrated the highest content of pectic galactan side chains. QTLs on tomato chromosomes 1, 2, 4 and 9 contain important genes controlling glucuronoxylan and pectic neutral side chains biosynthesis and/or metabolism. 相似文献
66.
Obert E Bellot M Bouteiller L Andrioletti F Lehen-Ferrenbach C Boué F 《Journal of the American Chemical Society》2007,129(50):15601-15605
A new bis-urea based supramolecular polymer is reported and shown by viscosimetry, neutron scattering (SANS), and calorimetry (ITC) to self-assemble in a wide range of solvents, encompassing the polarity scale from water to toluene. The presence of both hydrogen-bonding and hydrophobic groups ensures that self-assembly occurs in water, aprotic polar solvents, and nonpolar solvents. Both the driving force for the assembly and the exact structure of the filaments is solvent dependent, but whatever the solvent, long rigid filaments are formed in dynamic equilibrium with the monomer. 相似文献
67.
Mathilde Lecourt Giorgiana Chietera Bernard Blerot Sylvain Antoniotti 《Molecules (Basel, Switzerland)》2021,26(19)
Laccase-based biocatalytic reactions have been tested with and without mediators and optimized in the oxidation of allylbenzene derivatives, such as methyl eugenol taken as a model substrate. The reaction primarily consisted in the hydroxylation of the propenyl side chain, either upon isomerization of the double bond or not. Two pathways were then observed; oxidation of both allylic alcohol intermediates could either lead to the corresponding α,β-unsaturated carbonyl compound, or the corresponding benzaldehyde derivative by oxidative cleavage. Such a process constitutes a green equivalent of ozonolysis or other dangerous or waste-generating oxidation reactions. The conversion rate was sensitive to the substitution patterns of the benzenic ring and subsequent electronic effects. 相似文献
68.
Jonathan Leblanc Mathilde Mercier Christian Fonteix Fernand Pla 《Macromolecular Symposia》2007,259(1):85-93
Summary: This work deals with the development of the dispersed phase morphology in immiscible blends of poly(ethylene glycol)/polyamide 66 (PEG/PA) with an extremely low viscosity ratio. The blends were obtained, under different operating conditions, by melt blending in an internal mixer. The objective was to examine the influence of the main processing parameters on the particles size of the minor phase (PEG). A model was elaborated to describe the dependence of the particle size on interfacial tension, PEG concentration, shear rate and viscosity ratio between the two blend components. 相似文献
69.
Mathilde Courel Manuel Dornier Jean-Marie Herry Gilbert Marcel Rios Max Reynes 《Journal of membrane science》2000,170(2):281-289
A recent membrane technique, osmotic distillation (OD), is used to concentrate binary water–sucrose solutions at ambient temperature under atmospheric pressure. The principle is based on the extraction of water vapour from a dilute aqueous solution, which is put in contact with a hypertonic salt solution by means of a macroporous hydrophobic membrane. The concentration difference between both solutions translates into a transmembrane vapour pressure drop, that constitutes the driving force for mass transfer. An experimental device is designed at laboratory scale for this study, allowing achievement of vapour fluxes of 10 kg m−2 h−1 under standard conditions. The effect of various operating parameters on vapour flux is studied. The solute content results in the most influencing variable via water activity in brine and via viscosity in sugar solutions. The effect of concentration polarisation on the brine side is not negligible and would have to be taken into account for process optimisation. This phenomenon could not be quantified on the sugar solution side due to pressure drop limits of the pilot rig. Eventually, the vapour flux can be significantly increased by adding a temperature difference to the transmembrane concentration difference, when pure water is evaporated. 相似文献
70.
Mathilde Gadrat Catherine Emo Joël Lavergne Pierre-Louis Teissdre Klopatra Chira 《Molecules (Basel, Switzerland)》2022,27(8)
It is well established that C-glucosidic ellagitannins contribute to wine quality, and new forms of ellagitannins have been found recently in cognac eaux-de-vie. The contribution of some ellagitannin-derived spirit compounds to eaux-de-vie taste has been demonstrated recently. However, there is a gap in our knowledge of the content, composition, and evolution of C-glucosidic ellagitannins in this matrix. Indeed, the quantification of these compounds and their evolutionary compounds have never before been researched in cognac eaux-de-vie. Thus, the aim of this study was not only to quantify these compounds, but also to study their kinetics and to observe how they are impacted by barrel toasting. For this purpose, barrels representing eight different toasting levels were used to age the same eau-de-vie during the first 18 months. Ellagitannin quantification was carried out by HPLC-Triple quadrupole. The results showed that the evolutionary trend of the eight ellagitannins is the same for all eight types of barrel toasting. The maximum concentrations of C-glucosidic ellagitannins were found after 3 months of aging (up to 23 mg/L) before decreasing to 18 months (9.7 mg/L), whereas ellagitannin-derived spirit compound concentrations increased throughout aging (up to 130.9 mg/L). In addition, barrel toasting had such an impact on ellagitannin content that barrels could be differentiated according to their levels. Eaux-de-vie in barrels with high toasting were lower in ellagitannins concentrations. 相似文献