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101.
Sbastien Muller Philippe Burg Julien Starck Denise Cagniant Pierre Magri Ren Gruber Jean-Michel Trichard 《Catalysis Today》2007,119(1-4):291
Several samples of exhaust diesel soot are investigated by inverse gas chromatography and linear solvation energy relationship (LSER) modelling according to their soluble organic fraction content and their time of exposure in oxidative conditions. The results demonstrate the evolution of the adsorptive properties of the studied materials towards volatile compounds during the oxidation under NO2. 相似文献
102.
Pierre D. Harvey Michael Knorr 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(6):1174-1197
This mini-review surveys 23 structures of 3D coordination polymers built upon mono-, di- as well as cyclic and acylic polythioethers. An emphasis is put on the Secondary Building Units (SBU) and the physical properties. Importantly, the key feature is that the dominant SBU is not the rhomboid (Cu2X2S4), but an inorganic polymer containing at least the chain of the type (CuX) n . In the latter type of SBU, these chain formations are observed for X = I, but predominantly for X = CN. In addition, a large portion of the surveyed materials exhibit rich photophysical properties, but on several occasions, these materials exhibit properties often attributed to MOFs, mainly solvent exchange. 相似文献
103.
Application of a weighted‐average model (WAM) to the kinetic evolution of the elasticity during 16 h was successfully performed for a composite gel in which a maltodextrin phase is dispersed within a continuous gelatin phase. The results obtained using the model for different starting compositions along an initial higher‐temperature binodal are in good agreement with the phase diagram measured at high temperature and help to confirm the position of the binodal. A novel application of confocal Raman microscopy was used to measure the local concentration of the included phase of the composite gel and confirms the results given by the WAM. This model allows calculation of tie lines appropriate to the gel state and could be used for other biopolymer blends if the assumption is made that the gelation process involves a complete phase separation of both polymers before any gelation occurs. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1465–1477, 2000 相似文献
104.
105.
Steven Corthals Joris Van Nederkassel Jan Geboers Hendrik De Winne Jasper Van Noyen Bart Moens Bert Sels Pierre Jacobs 《Catalysis Today》2008,138(1-2):28
Dry reforming of methane was studied over Ni catalysts supported on γAl2O3, CeO2, ZrO2 and MgAl2O4 (670 °C, 1.5 bar, 16–20 l CH4 mlcatalyst−1 h−1). It is shown that MgAl2O4 supported Ni catalysts promoted with both CeO2 and ZrO2 are promising catalysts for dry reforming of methane with carbon dioxide. Within a certain composition range, the simultaneous promotion with CeO2 and ZrO2 has great influence on the amount of coke and the catalyst service time. XRD analyses indicate that formation of crystalline CexZr1−xO2 mixed oxide phases occurs on double promotion. In particular, incorporation of low amounts of Zr in the CeO2 fluorite structure provides stable dry reforming catalysis. As shown with TPR, promotion leads to a higher reduced state of Ni. SEM, XRD and TPR analyses demonstrate that highly dispersed, doubly promoted Ni catalysts with a strong metal-support interaction are essential for stable dry reforming and suppression of the formation of carbon filaments. 相似文献
106.
Platinum particles synthesized via the Bönnemann methods were dispersed on two different Vulcan XC72 carbon supports. One was used after thermal treatment at 400 °C under nitrogen atmosphere, the other after oxidation of its surface by acid leaching using diluted HNO3 in water (1/3). Characterization of the carbon support indicated that HNO3 treatment leads to the decrease of the BET surface and to the increase of the surface acidity of the carbon support. After dispersion of the platinum catalyst, TEM results indicated that the mean particle size was a little higher on the non-oxidized support (Pt/XC72) than that on the functionalized one (Pt/XC72HNO3), being 2.5 and 2.0 nm, respectively. However, potential cycles from 0.05 to 1.25 V vs. RHE led to a higher increase of the particle size when catalyst is dispersed on the functionalized support, reaching after 400 potential cycles 5.5 nm against 4.0 nm with the non-functionalized one. The effect of the upper limit (1.0 and 1.25 V vs. RHE) of the potential cycles on the active surface area and on the activity towards the oxygen reduction reaction (orr) was determined for both catalysts. Results indicated that the particle growth was not the main degradation process over the whole duration of the electrochemical experiments, but that dissolution/redeposition (Otswald ripening) was also involved. The predominant role of each degradation process depends on the number of cycles, on the upper potential limit and on the carbon surface state, and could be temporally separated. However, the lower activity towards orr was recorded for the (Pt/XC72HNO3) cycled up to 1.0 V vs. RHE. 相似文献
107.
108.
Hans E. Hoydonckx Dirk E. De Vos Suhas A. Chavan Pierre A. Jacobs 《Topics in Catalysis》2004,27(1-4):83-96
An overview is given of newly developed Lewis or Brønsted acid and base catalysts for esterification, transesterification and ester interchange reactions. The most relevant applications of these catalysts and reactions in the domain of renewable resources, in particular, oils and fats, are discussed. 相似文献
109.
Pierre Santucci Christina Dedaki Alexandros Athanasoulis Laura Gallorini Anaïs Munoz Dr. Stéphane Canaan Dr. Jean-François Cavalier Dr. Victoria Magrioti 《ChemMedChem》2019,14(3):349-358
In the quest for new antibacterial agents, a series of novel long- and medium-chain mono- and disubstituted β-lactones was developed. Their activity against three pathogenic mycobacteria—M. abscessus, M. marinum, and M. tuberculosis—was assessed by the resazurin microtiter assay (REMA). Among the 16 β-lactones synthesized, only 3-hexadecyloxetan-2-one (VM005) exhibited promising activity against M. abscessus, whereas most of the β-lactones showed interesting activities against M. marinum, similar to that of the classical antibiotic, isoniazid. Regarding M. tuberculosis, six compounds were found to be active against this mycobacterium, with β-lactone VM008 [trans-(Z)-3-(hexadec-7-en-1-yl)-4-propyloxetan-2-one] being the best growth inhibitor. The promising antibacterial activities of the best compounds in this series suggest that these molecules may serve as leads for the development of much more efficient antimycobacterial agents. 相似文献