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991.
M. Gueye T. Gries C. Noël S. Migot-Choux S. Bulou E. Lecoq P. Choquet K. Kutasi T. Belmonte 《Plasma Chemistry and Plasma Processing》2016,36(4):1031-1050
The interaction of (3-Aminopropyl)triethoxysilane (APTES) with pulsed late Ar–O2 afterglow is characterized by the synthesis of OH, CO and CO2 in the gas phase as main by-products. Other minor species like CH, CN and C2H are also produced. We suggest that OH radicals are produced in a first step by dehydrogenation of APTES after interaction with oxygen atoms. In a second step, the molecule is oxidized by any O2 state, to form peroxides that transform into by-products, break thus the precursor C–C bonds. If oxidation is limited, i.e. a low duty cycle, fragmentation of the precursor is limited and produced nanoparticles keep the backbone structure of the precursor, but contain amide groups produced from the amine groups initially available in APTES. At high duty cycle, silicon-containing fragments contain some carbon and react together and produce nanoparticles with a non-silica-like structure. 相似文献
992.
Lylian Challier Justin Lemarchand Catherine Deanno Cecile Jauzein Giorgio Mattana Guillaume Mériguet Benjamin Rotenberg Vincent Noël 《Particle & Particle Systems Characterization》2021,38(2):2000235
Inkjet-printing is used to fabricate dielectrophoretic electrodes able to trap polystyrene (PS) microparticles as well as model planktonic cells. The possibility of rapid prototyping offered by inkjet-printing allows the rational design of microchannels with tailored electric field distributions experienced by the suspended particles, which in turn provides a handle to drive them towards target regions. Specifically, this goal is achieved using two facing substrates constituting the bottom and the top walls of the channel, with a pair of interdigitated electrodes previously patterned by inkjet-printing on each side. Influence of electrode polarization (magnitude and frequency of the input signal) is investigated both theoretically, by modeling the electric field distribution inside the channel, and experimentally using confocal fluorescence microscopy. The printed device is able to sort circulating PS particles as a function of their size, with diameters ranging from 0.5 to 5 µm, as well as to separate planktonic species according to their composition (Alexandrium minutum versus Prorocentrum micans). This work paves the way for the development of large-area, microstructured dielectrophoretic electrodes able to separate the constituents of samples at flow rates up to 150 µL mn−1. 相似文献
993.
Comprehensive Two-dimensional Gas Chromatography for Analysis of the Volatile Compounds and Fishy Odor Off-flavors from Heated Rapeseed Oil 总被引:1,自引:0,他引:1
994.
995.
Cover Picture: Sulfoxide‐Directed Metal‐Free ortho‐Propargylation of Aromatics and Heteroaromatics (Chem. Eur. J. 20/2015)
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996.
997.
Abdelhak Ayadi Sana Elgasri Abderrazek Mezghani Mickaël Castro Foued Elhaouani 《ournal of non Newtonian Fluid Mechanics》2011,166(12-13):661-666
The gross melt fracture defect is related to the flow instabilities developed in the contraction region. To mitigate these upstream instabilities, a convergent radial flow in the die entrance has been created. In fact, the ultimate objective of the present work is to examine the effect of the clearance width of radial flow on the appearance and development of gross melt fracture defect. So, capillary rheometer experiments were performed with linear polydimethylsiloxane (PDMS) oil.As for the influence of radial flow width on the morphology of gross melt fracture defect, extrudate photographs show that this imperfection can be mitigated since its frequency is higher and amplitude smaller when the gap of radial flow decreases. Such results may be related both to shear and elongational components of radial flow. Actually, when gap width is very small compared to the external diameter of radial flow, shear deformations become more enhanced with respect to the elongational deformations and thus the helical gross melt fracture becomes more like a surface defect than volume defect. 相似文献
998.
999.
Fabien Rodier Michel Rajzmann Dr. Jean‐Luc Parrain Dr. Gaëlle Chouraqui Dr. Laurent Commeiras 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(7):2467-2477
The synthetic utility of γ‐alkylidenebutenolides is demonstrated as highly competent dipolarophile partners in both intra‐ and intermolecular rhodium(II)‐catalyzed 1,3‐dipolar cycloaddition reactions. The strength of this approach lies in the formation of spiro[6,4]lactone moieties with the concomitant construction of quaternary spiro stereocenters. Typically, the construction of spirolactones involves an esterification step, which has often been reported as a “biosynthetic pathway”, and often occurs either as or near to the final step of a total synthesis. Furthermore, a convergent and versatile route is reported for the formation of the (5,7) skeleton of molecules that were isolated from the Schisandra genus. Computational studies were performed to provide an overall picture of the mechanism of the intermolecular [3+2] cycloaddition between 2‐diazo‐1,3‐ketoester and protoanemonin and to rationalize the empirical observations. In particular, we have demonstrated for the first time that the rhodium center plays an important role during the cyclization step itself and reacts with the dipolarophile as a complex with the ylide. 相似文献
1000.
In this study, the quaternary solid solutions of (Bi2O3)(0.8?x)(Tb4O7)0.1(Ho2O3)0.1(Dy2O3)x (x = 0.05, 0.10, 0.15, 0.20) as an electrolyte were synthesized for solid oxide fuel cells by the technique of solid-state synthesis.The products were characterized by X-ray powder diffraction, differential thermal analysis/thermal gravimetry and the four-point probe technique (4PPT). The total electrical conductivity is measured on the temperature and the doped concentration by 4PPT.All samples have been obtained as the δ-phase. According to the measurements of the 4PPT, the electrical conductivities of the samples increase with the temperature but decrease with the amount of doping rate. The value of the highest conductivity (σ) is found as 1.02?×?10?1 S cm?1 for the system of (Bi2O3)0.75(Tb4O7)0.1(Ho2O3)0.1(Dy2O3)0.05 at 850 °C. The thermal gravimetry (TG) curve shows that there is no mass loss of sample during the measurement. The analyses of differential thermal reveal that there are neither endothermic peaks nor exothermic peaks during the heating and cooling cycles (ranging from 30 to 1000 °C). 相似文献