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51.
We study permutations that are sorted by operators of the form S ° α ° S, where S is the usual stack sorting operator introduced by Knuth and α is any D 8-symmetry obtained by combining the classical reverse, complement, and inverse operations. Such permutations can be characterized by excluded (generalized) patterns. Some conjectures about the enumeration of these permutations, refined with numerous classical statistics, have been proposed by Claesson, Dukes, and Steingrímsson. We prove these conjectures, and enrich one of them with a few more statistics. The proofs mostly rely on generating trees techniques, and on a recent bijection of Giraudo between Baxter and twisted Baxter permutations. 相似文献
52.
53.
Paul Berceau Rémy Battesti Mathilde Fouché Paul Frings Marc Nardone Oliver Portugall Geert L. J. A. Rikken Carlo Rizzo 《Hyperfine Interactions》2012,207(1-3):7-12
From a series of M?ssbauer measurements performed on a single crystal of FePSe3, we have observed the effect of electromagnetically induced transparency (EIT) in a second nuclear system, after a first experiment using the mineral siderite FeCO3. When the condition of nuclear level crossing was fulfilled, an obvious deficit in absorption was observed at the point of level crossing. This reduced absorption cannot be ascribed to saturation effects because of the specific geometry of the measurement. We conclude that the observed deficit in absorption is due to coherence and interference effects. 相似文献
54.
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
55.
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
56.
Vernet Mathilde Pigné Yoann Sanlaville Éric 《4OR: A Quarterly Journal of Operations Research》2023,21(2):205-233
4OR - This work focuses on connectivity in a dynamic graph. An undirected graph is defined on a finite and discrete time interval. Edges can appear and disappear over time. The first objective of... 相似文献
57.
Jun Sun Xiaoyu Gu Mathieu Coquelle Serge Bourbigot Sophie Duquesne Mathilde Casetta Sheng Zhang 《先进技术聚合物》2014,25(12):1552-1559
Melamine polyphosphate (MPP) and halloysite nanotubes (HNT) were introduced to polyamide 6 (PA6) by melt blending in order to improve the fire resistance. PA6 composite containing 12% flame retardants with good spinnability was obtained. The flammability of PA6 composite was characterized by limiting oxygen index (LOI), UL‐94 vertical burning and cone calorimeter (CONE) tests. The results indicated that the LOI value could reach 24.0 vol.% and UL‐94 rating could achieve V2 level at the presence of 12% flame retardants. CONE data demonstrated that peak heat release rate was significantly reduced from 554 kW/m2 of neat PA6 to 368 kW/m2 of the sample containing flame retardants. Thermal analysis indicated that the thermal stability and char formation were improved by the presence of flame retardants. The morphology of residue char was characterized by scanning electron microscopy; and it suggested that a network‐structured protective char layer had been formed. The possible synergism between MPP/HNT and their flame retardant mechanism was also analyzed and discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
58.
Christian Reece Mathilde Luneau Cynthia M. Friend Robert J. Madix 《Angewandte Chemie (International ed. in English)》2020,59(27):10864-10867
Controlling the selectivity of catalytic reactions is a critical aspect of improving energy efficiency in the chemical industry; thus, predictive models are of key importance. Herein the performance of a heterogeneous, nanoporous Au catalyst is predicted for the complex catalytic self‐coupling of the series of C2–C4 alkyl alcohols, based solely on the known kinetics of the elementary steps of the catalytic cycle for methanol coupling, using scaling methods augmented by density functional theory. Notably, a sharp decrease in selectivity for ester formation with increasing molecular weight to favor the aldehyde due to van der Waals interactions of reaction intermediates with the surface was predicted and subsequently verified quantitatively by experiment. Further, the agreement between theory and experiment clearly demonstrates the efficacy of this approach for building a predictive model of catalytic behavior for a homologous set of reactants using a small set of experimental information. 相似文献
59.
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
60.
Busson M Berisha A Combellas C Kanoufi F Pinson J 《Chemical communications (Cambridge, England)》2011,47(47):12631-12633
4-Nitrobenzenediazonium may be photochemically grafted onto gold, copper and iron under visible and UV light. Thin nanometre layers are obtained and characterized by IRRAS, electrochemistry and ellipsometry. 相似文献