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1.
Bouaziz Youssef Royer Eric Bresson Guillaume Dhome Michel 《Multimedia Tools and Applications》2022,81(16):22449-22480
Multimedia Tools and Applications - Changes in appearance present a tremendous problem for the visual localization of an autonomous vehicle in outdoor environments. Data association between the... 相似文献
2.
Vincent Cantarel David Lambertin Arnaud Poulesquen Fabrice Leroux Guillaume Renaudin Fabien Frizon 《Ceramics International》2018,44(9):10558-10568
This work investigates emulsion templating to synthesize hexadecane oil/geopolymer composites. In a system with hexadecane as the internal (dispersed) phase and an alkali activated continuous phase without added surfactant, adding aluminosilicate clay particles does not increase resistance against creaming or coalescence, while adding a surfactant (L35 or CTAB) stabilizes the solid-liquid interface. Infrared studies and rheological studies of the associated geopolymerization determined that the presence of the organic phase or surfactant has no significant effect on the geopolymerization kinetics, as determined by the change in time of the Si-O-T IR stretching frequency and the rheological moduli involved during the process. The stabilization of the organic template is reminiscent of Pickering emulsion even though we employ a much greater amount of inorganic material for geopolymer formation. Although the addition of surfactant has a significant effect on the behavior of the paste, the percolation of the network remains unmodified, highlighting the fact that the phenomenon is not dependent on viscosity. Finally, rheological measurements were used to obtain the mass fractal dimension of the as-made gel network, which is able to differentiate the interfacial effect between surfactant molecules with a slightly denser interphase when a cationic surfactant is used. 相似文献
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The extinction coefficient ? at 2.9 μm for OH in fluoride glasses is measured by determining the amount of HF evolved during heating of the glass under steam and the corresponding intensity of the OH absorption band. This coefficient is respectively equal to 31 litre mole?1 cm?1 for BTYbZ glass (15 BaF2 - 29 ThF4 - 28 YbF3 - 28 ZnF2) and 19.5 litre mole?1 cm?1 for BALLA glass (34 BaF2 - 57 ZrF4 - 4 AlF3 - 5 LaF3). 相似文献
6.
An assessment of the Fe-C-Si system 总被引:1,自引:0,他引:1
7.
Andr Hamwi Catherine Latouche B atrice Burteaux Jacques Dupuis 《Fullerenes, Nanotubes and Carbon Nanostructures》1996,4(6):1213-1226
Reaction of metallic fluorides: WF6 TaF5, NbF5 and TiF4 with C60/C70 extract was performed at appropriate temperatures. M0F5 and BF3 fluorides do not react. Chemical formulas based on mass uptake show MFn/C60 ratios up to 2.00. Compounds were analysed by means of X-ray diffraction, FT-IR and NMR spectroscopies. The presence of neutral fluorides and associated anionic species is put forward and it is shown that MFn compounds do not act as fluorination agents. Electrical conductivity measurements are also presented. 相似文献
8.
Data transmission networks and systems are often subject to perturbations due to the fact that (low level) data signals are surrounded by perturbing electromagnetic fields. This paper presents and analyses information perturbing mechanisms. The authors examine data streams transmitted by an elementary system which represents the basis of any electronic device. We show the influence of technological families of cmos circuits and present a test method and bench to investigate the sensitivity of devices under test by means of statistical parameters. 相似文献
9.
Tony Maillet Jacques Barbier Jr. Daniel Duprez 《Applied catalysis. B, Environmental》1996,9(1-4):251-266
A 1% Pd catalyst (38% dispersion) was prepared by impregnating a γ-alumina with palladium acetylacetonate dissolved in acetone. The behaviour of this catalyst in oxidation and steam reforming (SR) of propane was investigated. Temperature-programmed reactions of C3H8 with O2 or with O2 + H2O were carried out with different stoichiometric ratios S(S =[O2]/5[C3H8]). The conversion profiles of C3H8 for the reaction carried out in substoichiometry of O2 (S < 1) showed two discrete domains of conversion: oxidation at temperatures below 350°C and SR at temperatures above 350°C. The presence of steam in the inlet gases is not necessary for SR to occur: there is sufficient water produced in the oxidation to form H2 and carbon oxides by this reaction. Contrary to what was observed with Pt, an apparent deactivation between 310 and 385°C could be observed with Pd in oxidation. This is due to a reduction of PdOx into Pd0, which is much less active than the oxide in propane oxidation. Steam added to the reactants inhibits oxidation while it prevents the reduction of PdOx into Pd0. Compared to Pt and to Rh, Pd has a higher thermal resistance: no deactivation occurred after treatment up to 700°C and limited deactivation after treatment up to 900°C, provided that the catalyst is maintained in an oxygen-rich atmosphere during the cooling. 相似文献
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