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Selective catalytic reduction of nitrogen oxides over a modified silicoaluminophosphate commercial zeolite

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Journal of Environmental Sciences 2018年第3期30卷 246-252页

作者： Carolina Petitto Gérard Delahay institut charles gerhardt Montpellier UMR 5253 CNRS/UM/ENSCM Matériaux Avancés pour la Catalyse et la Santé 8 rue de l'Ecole Normale

Nitrogen oxides（NOx：NO,NO2）are a concern due to their adverse health *** engine transport sector is the major emitter of *** regulations have been strengthened and to comply with them,one of the two methods commonly used is the selective catalytic reduction of NOxby NH3（NH3-SCR）,NH3being supplied by the in-situ hydrolysis of *** and durability of the catalyst for this process are highly *** is evaluated by hydrothermal treatment of the catalysts at temperature above 800℃.In this study,very active catalysts for the NH3-SCR of NOxwere prepared by using a silicoaluminophosphate commercial zeolite as copper host *** by X-ray diffraction（XRD）,scanning electron microscopy（SEM）and temperature programmed desorption of ammonia（NH3-TPD）showed that this commercial zeolite was hydrothermally stable up to 850℃ and,was able to retain some structural properties up to950℃.After hydrothermal treatment at 850℃,the NOxreduction efficiency into NH3-SCR depends on the copper *** catalyst with a copper content of 1.25 wt.%was the most *** difference in activity was much more important when using NO than the fast NO/NO2reaction mixture.

关键词： Diesel Nitrogen oxides SCR process Copper Zeolite Silicoaluminophosphate

Selective catalytic reduction of NO by NH3 on cerium modified faujasite zeolite prepared from aluminum scraps and industrial metasilicate

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Journal of Rare Earths 2020年第3期38卷 250-256页

作者： Rahma Abid Gerard Delahay Hassib Tounsi Laboratory of Advanced Materials National School of Engineers of SfaxUniversity of SfaxTunisia institut charles gerhardt ENSCM"Advanced Materials for Health and Catalysis"240 Av Professor Emile Jeanbrau34296 MontpellierFrance

This work was devoted to the study of the selective catalytic reduction of NO by NH3 on calcined and hydrothermal treated cerium loaded zeolite *** parent faujasite zeolite Na-F(Si/Al=1.32 and SBET=749 m^2/g) used as support for the preparation of the catalysts was obtained from industrial sodium metasilicate and aluminum *** expected,the NO conversion increases with increasing the percentage of cerium in the structure of the faujasite *** NO conversion into N2 is reached at 400℃at a space velocity of 250 000 h^-*** high conversion is due to the redox shift between Ce^3+/Ce^4+and the strong acid sites related to the rare earth present in the framework that is the key in SCR of NO ***,the highest loaded cerium catalyst retains almost its activity after hydrothermal treatment at 850℃.This higher loading is desirable for both activity and stability provided that two stages of preparation are used to put the Ce ions in the sodalite cages.

关键词： Aluminum scraps Ce-Y NH3-SCR Hydrothermal stability

Dialkyl imidazolium acetate ionosilica as efficient and recyclable organocatalyst for cyanosilylation reactions of ketones

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Green Energy & Environment 2020年第2期5卷 130-137页

作者： Thanh Tran Duy Alysson Duarte Rodrigues Giang Vo-Thanh Peter Hesemann institut de Chimie Moléculaire et des Matériaux D'Orsay UniversitéParis-SaclayUMR 818291405 Orsay CedexFrance institut charles gerhardt de Montpellier Universitéde MontpellierUMR 5253 CNRS-UM-ENSCMPlace E.Bataillon34000 MontpellierFrance

We report new heterogeneous organocatalyst based on silica hybrid supported N-heterocyclic carbene(NHC-)*** organocatalyst is formed from an imidazolium iodide based ionosilica material,followed by iodide/acetate anion *** imidazolium acetate generates the organocatalytic carbene via partial deprotonation of the imidazolium ring in *** monitored via EDX,solid state NMR and ion chromatography measurements,the iodide/acetate exchange involving the imidazolium ionosilica material took place only in small *** the fact that the exchanged material contains only a very small amount of acetate,we observed good catalytic activity and recyclability in cyanosilylation reactions of ketones with trimethylsilyl *** versatility of the catalyst was highlighted via reaction with several substrates,yielding the corresponding cyanohydrins in good *** recycling experiments,the material showed decreasing catalytic activity starting from the third reaction cycle,but high catalytic activity can be regenerated via another acetate *** work is important as it highlights the possibility to combine carbene chemistry and silica,which are antagonistic at a first *** show that imidazolium acetate based ionosilicas are therefore heterogeneous'proto-carbenes',and that there is no need to form strongly basic silica supported NHCs to obtain heterogeneous *** work therefore opens the route towards heterogeneous and re-usable NHC-organocatalysts from supported ionic liquid imidazolium acetates.

关键词： N-heterocyclic carbenes Ionosilica Heterogeneous organocatalysis Cyanosilylation Ionic liquids

Active MoS_(2)-based electrode for green ammonia synthesis

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Chinese Journal of Chemical Engineering 2024年第1期65卷 268-275页

作者： Xin Liu Lei Yang Tao Wei Shanping Liu Beibei Xiao School of Energy and Power Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China institute charles gerhardt Montpellier UMR-5253Universite de MontpellierCNRSENSCMPlace E.Bataillon34095 Montpellier Cedex 05France

Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia *** critical aspect to unlocking this technology is to discover the catalysts with high selectivity and *** this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal *** results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR ***,MoS_(2)functionalized via edge W-substitution exhibits an exceptional *** energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 ***,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments.

关键词： Nitrogen reduction reaction Density functional theory calculations Molybdenum disulfide Electrochemistry Catalyst Thermodynamics

UNUSUAL CRYSTALLIZATION AND MELTING PROCESSES OF AN OPTICALLY ACTIVE POLYOLEFIN:ISOTACTIC POLY((S)-4-METHYL-HEXENE-1)

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Chinese Journal of Polymer Science 2005年第2期23卷 165-170页

作者： Annamaria Buono JrjengRuan AnnetteThierry Peter Neuenschwander Bernard Lotz institut charles Sadron and Dipartimento di Chimica Universita di Napoli Federico ⅡVia Cynthia 5NapoliItalyInstitut Charles Sadron(CNRS-ULP)6Rue Boussingault67083 StrasbourgFranceInstitut Charles Sadron(CNRS-ULP)6Rue Boussingault67083 StrasbourgFranceInstitute for PolymersETH ZentrumCNB E 93.2Universitaetstrasse 6CH-8092 ZurichSwitzerlandInstitut Charles Sadron(CNRS-ULP)6Rue Boussingault67083 StrasbourgFrance

Polyolefins that bear a chiral side chain(typically an isobutyl group)experience a so-called macromolecularamplification of chirality:the chiral side-chain induces a slight preference for either tg or tg(?) main chain ***slight conformational bias is amplified cooperatively along the chain,and results in preferred chirality of the main chainhelical *** a result,these polymers display a liquid-crystal(LC)phase both in solution and,in the melt as atransient phase on the way to *** existence of two processes(melt-LC and LC-crystal transitions)results inunconventional behaviors that were first analyzed by Pino and collaborators back in *** polymers also offer a meansto test the structural consequences of recently introduced crystallization *** schemes postulate the formation of atransient liquid-crystal phase as a general scheme for polymer crystallization.

关键词： Liquid crystalline polyolefins Crystallization Melting Amplification of chirality.

A Fresh Look at the Structures of Nylons and the Brill Transition

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Advanced Fiber Materials 2021年第4期3卷 203-209页

作者： Bernard Lotz institut charles Sadron CNRS and Universitéde Strasbourg23Rue du Loess67034 StrasbourgFrance

The common knowledge of the crystal structures of nylons dates back to the early 1950s with the work of Bunn and *** describes the packing of sheets made of hydrogen-bonded stems in an extended chain *** alpha phase structures have a specific powder X-ray diffraction pattern with reflections at 4.4Åand 3.7Å.On heating,reflections trans-form progressively and merge at≈4.2Åat the so-called“Brill transition”.Other diffraction patterns have been recorded for different types of nylons and thermal *** patterns were interpreted only as indicating the existence of“variants”of the alpha ***,neither their structure,nor the origin of the Brill transition were *** structural analyses and molecular modeling approaches have provided new insights in these long-standing structural ***“variants”feature chain conformations that are“pleated”.The Brill transition does not involve the standard extended chains of the alpha phase but corresponds to a dynamic interconversion(≈10^(10)/s)between mirror conformations of these pleated stems.

关键词： Nylons Crystal structures Phase transitions Brill transition

Computational Study of the Molecular Complexes between 5-HTP with ATP and DHEA. Potential New Drug Resulting from This Complexation

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Computational Chemistry 2015年第1期3卷 18-22页

作者： Dan A. Lerner Constantin Balaceanu-Stolnici Josette Weinberg Luminita Patron institut charles gerhardt Montpellier Montpellier France Ecological University of Bucharest Bucharest Romania institute of Physical Chemistry Bucharest Romania

Extending the potential interest in new drugs resulting from the association of biologically important molecules in stable complexes, the present study shows that this concept previously implemented in the case of two components could be a meaningful and promising one in the case of three components. The choice was made here to show that the quantum chemical modeling of a tripartite complex with DHEA (DEHYDRO-EPIANDROSTERONE) in a ternary association with 5-hydro- xytryptophan (5-HTP) and adenosine triphosphate acid (ATP) could have a sizable stability.

关键词： 5-HTP ATP DHEA Density Functional Theory (DFT)

Compressive behavior and energy absorption of metal porous polymer composite with interpenetrating network structure

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中国有色金属学会会刊：英文版 2006年第B2期16卷 439-443页

作者： LIU Yu GONG Xiao-lu institut charles Delaunay CNRS FRE 2848 LASMIS UTT 12 rue Marie Curie BP 2060 10010 Troyes France

Interpenetrating phase composites (IPCs) are a new class of composite materials with improved combinations of mechanical and physical properties. This study was performed on a new type of IPC called metal porous polymer composite (MPPC) with an interpenetrating network structure. Aluminum-polypropylene (AI-PE) and Aluminum-epoxy resin (Al-Ep) composites were produced by infiltrating the polymer in the aluminum foam. The composite microstructures were characterized using SEM observation. The compressive behavior and energy absorption characteristics of MPPC were investigated and compared with the aluminum foams. The compressive modulus of composite was compared with the VOIGT-REUSS bounds and HASHIN-SHTRIKMAN (H-S) bounds models. The experimental modulus of compressive tests falls well within the theoretical models.

关键词：金属多孔聚合物复合物互穿网络结构压缩行为能量吸收 MPPC复合物

New Highly Resistive Zirconia Fused Cast Products for Alkali Free Glass Melting

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材料科学与工程（中英文B版） 2011年第7期1卷 871-878页

作者： Isabelle Cabodi Michel Gaubil Christel Morand Andrea Gioia Julien Haines Philippe Papet Saint-Gobain CREE Cavaillon 84 France institut charles gerhardt University Montpellier II Sciences et Techniques du Languedoc 34 France