References of "Lambert, Stéphanie"
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See detailHydrodechlorination and complete degradation of chlorinated compounds with the coupled action of Pd/SiO2 and Fe/SiO2 catalysts: towards industrial catalyst synthesis conditions
Mahy, Julien ULiege; Tasseroul, Ludivine; Tromme, Olivier et al

in Journal of Environmental Chemical Engineering (2019), 7(1),

In this study, Pd/SiO2 and Fe/SiO2 catalysts have been synthesized by the cogelation process for hydrodechlorination applications. Different synthesis conditions were tested to approach the industrial ... [more ▼]

In this study, Pd/SiO2 and Fe/SiO2 catalysts have been synthesized by the cogelation process for hydrodechlorination applications. Different synthesis conditions were tested to approach the industrial conditions using industrial grade reactants and ambient air drying. The influence of these changes have been studied on the texture and the catalytic activity of the catalysts. The resulting materials are composed of metallic (Pd catalysts) or metallic oxide (Fe catalysts) nanoparticles highly dispersed in porous silica. The catalysts present a high specific surface area (between 250 and 500 m2/g) with a large pore size range between micro-, meso- and macropores. The modifications of the synthesis conditions give catalysts with similar textural properties compared to lab-scale catalysts. The catalytic activity of the binary catalysts have been evaluated on the hydrodechlorination of the 2,4,6-trichlorophenol (TCP) in water. Results show that Pd/SiO2 catalysts are able to dechlorinate the TCP and that Fe/SiO2 materials are able to degrade the resulting phenol. So this process allows a complete degradation of TCP. Industrial conditions catalysts show also similar catalytic results compared to lab-scale catalysts for the hydrodechlorination of the 2,4,6-trichlorophenol (TCP) in water. [less ▲]

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See detailPorphyrin-based hybrid silica-titania as a visible-light photocatalyst
Mahy, Julien ULiege; Pàez Martinez, Carlos ULiege; Carcel, Carole et al

in Journal of Photochemistry and Photobiology A: Chemistry (2019), 373

A silylated porphyrin derivative is co-hydrolyzed with Ti(OiPr)4 to produce a hybrid TiO2 photocatalyst, and three different ratios between porphyrin and TiO2 are made. In this way, the porphyrin ... [more ▼]

A silylated porphyrin derivative is co-hydrolyzed with Ti(OiPr)4 to produce a hybrid TiO2 photocatalyst, and three different ratios between porphyrin and TiO2 are made. In this way, the porphyrin fragments are held in the resulting matrix through strong Si-O-Ti covalent bonds to limit porphyrin leaching. Thanks to its photoactive character the porphyrin fragment can act as an actuator for the TiO2 to degrade organic pollutants using light from ultra-violet to the visible range. The photocatalysts are synthesized using an easy aqueous route allowing “green conditions” for synthesis. For comparative purposes, the corresponding pure TiO2 and a grafted catalyst are also synthesized and studied. For all samples, a mixture of anatase/brookite TiO2 is obtained, resulting in crystalline materials with low temperature synthesis. The three porphyrin-doped samples prepared in water prove to be efficient photocatalysts for the degradation of p-nitrophenol (PNP) under visible light, and an improvement in photoactivity is observed when the amount of porphyrin increases. The photocatalyst activity is very stable over time as the PNP degradation remains nearly constant after 264 h of testing, showing no leaching of porphyrin. In recycling tests, the grafted sample presents bond breaking between POR-Si and TiO2 and a decrease in photoactivity towards pure TiO2 sample activity. A comparison with the commercial Evonik P25 catalyst shows that the porphyrin-doped TiO2 is nearly 6 times more photoactive under visible light for PNP degradation. [less ▲]

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See detailSol-gel syntheses of photocatalysts for the removal of pharmaceutical products in water
Belet, Artium ULiege; Wolfs, Cédric ULiege; Mahy, Julien ULiege et al

in Nanomaterials (2019), 9

A screening study on seven photocatalysts was performed to identify the best candidate for pharmaceutical products degradation in water. Photocatalysts were deposited as thin films through a sol-gel ... [more ▼]

A screening study on seven photocatalysts was performed to identify the best candidate for pharmaceutical products degradation in water. Photocatalysts were deposited as thin films through a sol-gel process and subsequent dip-coating on glass slides. The efficiency of each photocatalyst was assessed through the degradation of methylene blue first, and then, through the degradation of fifteen different pharmaceutical products. Two main types of synthesis methods were considered: aqueous syntheses, where the reaction takes place in water, and organic syntheses, where reactions take place in an organic solvent and only a stoichiometric amount of water is added to the reaction medium. Photocatalysts synthesized via aqueous sol-gel routes showed relatively lower degradation efficiencies; however, the organic route required a calcination step at high temperature to form the photoactive crystalline phase, while the aqueous route did not. The best performances for the degradation of pharmaceuticals arose when Evonik P25 and silver nanoparticles were added to TiO2, which was synthesized using an organic solvent. In the case of methylene blue degradation, TiO2 modified with Evonik P25 and TiO2 doped with MnO2 nanoparticles were the two best candidates. [less ▲]

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See detailDurable photocatalytic thin coatings for road applications
Mahy, Julien ULiege; Pàez Martinez, Carlos ULiege; Hollevoet, Jonas et al

in Construction and Building Materials (2019), 215

In this study, 6 different coatings have been developed as photocatalytic coatings based on TiO2, which can be applied to concrete for road applications. The goal of these coatings is to degrade ... [more ▼]

In this study, 6 different coatings have been developed as photocatalytic coatings based on TiO2, which can be applied to concrete for road applications. The goal of these coatings is to degrade pollutants such as nitrogen oxides and volatile organic compounds emitted by road transport. The coatings are synthesized by sol-gel process in organic or water solvent or by a functionalization technique with hydroxybenzoic acid on commercial TiO2 nanoparticles (P25). These suspensions are deposited by dip-coating or spray-coating on three different concrete substrates: pavement blocks, brushed or exposed aggregates road concrete. For each process, particular attention has been paid to the development of TiO2 synthesis that will be easily produced on a larger scale. The samples are characterized with photocatalytic test on NOx degradation, mechanical resistance test and resistance to freeze-thaw cycles in presence of de-icing salts. Except from the samples resulting from the sol-gel organic route, all other samples show a NOx degradation between 10 and 45%. From resistance point of view, the best coating is the TiO2 P25/E coating synthesized by functionalization of P25 nanoparticles. Results highlight that anatase TiO2 is well present at the surface of the sample and an optimal TiO2 loading exists for this coating. The TiO2 P25/E coating shows promising properties for road applications. [less ▲]

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See detailSynthesis of Ni/γ-Al2O3-SiO2 catalysts with different silicon precursors for the steam toluene reforming
Claude, Vincent; Mahy, Julien ULiege; Geens, Jérémy ULiege et al

in Microporous and Mesoporous Materials (2019), 284

This work investigated the intrinsic properties and performances of Ni/γ-Al2O3-SiO2 modified with different silicon precursors for the steam reforming of toluene in biomass gasifier exit conditions (8000 ... [more ▼]

This work investigated the intrinsic properties and performances of Ni/γ-Al2O3-SiO2 modified with different silicon precursors for the steam reforming of toluene in biomass gasifier exit conditions (8000 ppmv of toluene, 650 °C). Samples were synthesized by an aqueous sol-gel process in presence of aluminum nitrate, nickel nitrate and the use of either tetramethoxysilane (TMOS, Si-(OCH3)4) or tetraethoxysilane (TEOS, Si-(OC2H5)4) in order to understand the influence of the reactivity of the silicon precursor. Furthermore, the use of N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDAS, (OCH3)3-Si-(CH2)3-NH-(CH2)2-NH2) is also investigated in order to understand the influence of a silicon precursor containing an ethylenediamine group, able to complex Ni2+ ions. By the chelation of Ni2+ ions by ethylenediamine groups during the synthesis, Ni/γ-Al2O3-SiO2 samples modified with EDAS showed higher dispersion of the metallic Ni nanoparticles and the higher resistance against the sintering of Ni particles. This was also attributed to the high microporous volume and the narrow mesoporous distribution of the support, which could also prevent the migration of the metallic Ni nanoparticles. The catalytic tests revealed that the reactivity of the silicon precursor played a major role on the conversion of toluene. For alumina supports modified with a silicon precursor with a low reactivity such as TEOS, the low integration of the Si atoms inside the bulk alumina lead to a slightly higher catalytic activity, but also to a high formation of structured carbon. The opposite effect was observed for the samples modified with a highly reactive silicon precursor, such as TMOS or EDAS, which showed a slightly lower catalytic activity, but a higher resistance against coking compared to pure Ni/γ-Al2O3 catalysts. [less ▲]

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See detailTailored films and biomaterials: another reality
Mahy, Julien ULiege; Wolfs, Cédric ULiege; Tilkin, Rémi ULiege et al

Poster (2018, December 10)

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See detailModification inorganique d’une argile locale: Application au traitement des eaux
Benhebal, Hadj; Kadi, Samir; Lellou, Salima et al

Poster (2018, December)

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See detailElaboration de matériaux zéolithiques à partir d'argiles locales: Application au traitement des eaux
Benhebal, Hadj; Kadi, Samir; Lellou, Salima et al

Poster (2018, December)

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See detailEncapsulation de protéines par procédé sol-gel pour l’application en reconstruction osseuse
Tilkin, Rémi ULiege; Regibeau, Nicolas ULiege; Grandfils, Christian ULiege et al

Conference (2018, November 21)

Ces dernières années, l’ingénierie tissulaire est devenue une des techniques les plus prometteuse pour le maintien et la reconstruction de tissus humains, voire même d’organes entiers. Cette solution est ... [more ▼]

Ces dernières années, l’ingénierie tissulaire est devenue une des techniques les plus prometteuse pour le maintien et la reconstruction de tissus humains, voire même d’organes entiers. Cette solution est fréquemment basée sur la réalisation de matrices poreuses, appelées « scaffolds ». De nombreux matériaux ont été proposés pour la conception de scaffolds, comme les biocéramiques (e.g. hydroxyapatite, β-tricalcium phosphate). Cependant, de nombreuses études ont montré que un manque de propriétés d'ostéoinduction, d’ostéogenèse et d’ostéointégrité. Cette étude vise à ajuster les propriétés de surface de biocéramiques par l’ajout d’un revêtement sol-gel de silice dans lequel seront encapsulées des protéines. Dans cette optique, l’étude de l’influence des paramètres d’encapsulation sur la cinétique de libération des protéines est une étape cruciale. L’encapsulation d’une protéine modèle (Soybean Trypsin Inhibitor) a été étudiée via deux méthodes : (1) l'imprégnation de gels de silice préalablement synthétisés, par une solution de protéine : méthode ex situ, (2) l'incorporation de la protéine lors de la synthèse du gel de silice : méthode in situ. Pour la méthode ex situ, le tétraéthylorthosilicate (TEOS) a été utilisé comme précurseur principal de la silice et le 3-(2-aminoéthylamino)propyltriméthoxysilane (EDAS) comme agent nucléant en milieu alcoolique et à pH basique. Les gels formés ont ensuite été séchés et/ou calcinés à différentes températures. Le type de traitement et la durée d'imprégnation ont été étudiés. Pour la méthode in situ, le tétraméthylorthosicilate (TMOS) a servi de précurseur au gel de silice après hydrolyse en pH acide. Les propriétés texturales des gels de silice ont été caractérisées par adsorption-désorption d'azote et porosimétrie au mercure. La cinétique de libération de la protéine a été analysée in vitro sur une durée de 4 semaines. Les résultats de porosimétrie au mercure et d’adsorption-désorption d’azote montrent que les gels ex situ présentent une structure poreuse en forme d'entonnoir (micro, méso et macropores) tandis que le gel in situ présente une structure microporeuse. Concernant la méthode ex-situ, les résultats montrent un « burst » après seulement 24 h suivi de l’établissement d’un plateau. Le pourcentage de protéine libérée après 7 jours d’incubation augmente lorsque la quantité de groupements aminés présents dans la silice diminue (i.e. augmentation de la température de calcination). L’effet du temps d’imprégnation ne se marque que dans le cas des gels contenant des fonctions amines avec une augmentation de la quantité de protéines absorbées avec le temps d’imprégnation. Pour la méthode in situ, un « burst » plus faible a été observé durant les premières 24 h, suivi par une libération continue de la protéine sur une période de 7 jours. Tilkin Rémi et Régibeau Nicolas bénéficie d’une bourse FRIA octroyée par le F.R.S.-FNRS. S. D. Lambert remercie également le FRS-FNRS pour sa position de Maître de Recherches. [less ▲]

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See detailEasy-cleaning and photocatalytic materials
Mahy, Julien ULiege; léonard, Géraldine; Zubiaur, Anthony ULiege et al

Conference (2018, November 20)

Dans ce travail, un procédé sol-gel en phase aqueuse a été développé pour produire à grande échelle un photocatalyseur à base de TiO2 présentant des propriétés hydrophiles et une activité photocatalytique ... [more ▼]

Dans ce travail, un procédé sol-gel en phase aqueuse a été développé pour produire à grande échelle un photocatalyseur à base de TiO2 présentant des propriétés hydrophiles et une activité photocatalytique élevée pour la dépollution de l'eau et de l'air. La première étape consistait à développer une synthèse sol-gel en phase aqueuse de TiO2 pur à l'échelle du laboratoire. Le protocole de synthèse a été simplifié pour réduire le temps de synthèse, la température et le nombre d’étapes comme les étapes de lavage. Les propriétés physico-chimiques et photocatalytiques du matériau obtenu ont été caractérisées pour évaluer la production d'un revêtement hydrophile sur acier inoxydable et la formation d'un photocatalyseur efficace sur la dégradation de trois polluants (bleu de méthylène, p-nitrophénol ou acétaldéhyde) sous différentes formes (film ou poudre) et dans différentes phases (liquide ou gazeuse). Dans la deuxième partie, la synthèse aqueuse a été adaptée pour produire des catalyseurs de TiO2 dopés avec des ions Fe3+, Ag+, Cu2+, Zn2+, Cr3+, Al3+, Mn2+ et Co2+ et des nanoparticules métalliques de Pt afin d'améliorer leur activité. Certains dopants ont montré une photoactivité accrue et certains mécanismes ont été proposés pour expliquer ces modifications de l'activité avec le dopage. En outre, la comparaison des coûts à l'échelle du laboratoire a montré que le dopage au Zn2+ pouvait être envisagé pour des applications industrielles. En utilisant cette méthode, un photocatalyseur de TiO2 dopé au Zn a été synthétisé à grande échelle et a montré des propriétés homologues au produit à l'échelle du laboratoire. La troisième étape consistait à étudier la propriété de redispersion des colloïdes de TiO2 nanocristallins. En effet, les poudres obtenues par séchage sous air de ces colloïdes peuvent être redispersées dans l'eau pour produire des colloïdes qui sont comparés à ceux obtenus initialement. Cinq cycles de séchage-redispersion ont été réalisés sur des colloïdes sélectionnés. Un mécanisme a été proposé pour expliquer cette propriété intéressante, l'acide présent dans la synthèse semble être le facteur principal. Cela peut être très utile pour une application industrielle de cette synthèse permettant de réduire le volume et le poids pour le transport et le stockage. [less ▲]

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See detailAqueous N-Doped TiO2 Catalysts for Visible Light Photocatalytic Applications
Mahy, Julien ULiege; Cerfontaine, Vincent; Poelman, Dirk et al

Poster (2018, November)

In this work, TiO2 prepared with an aqueous sol-gel synthesis by peptization process is doped with nitrogen precursor to extend its activity towards the visible region. Three N-precursors are used: urea ... [more ▼]

In this work, TiO2 prepared with an aqueous sol-gel synthesis by peptization process is doped with nitrogen precursor to extend its activity towards the visible region. Three N-precursors are used: urea, ethylenediamine and triethylamine. Different molar N/Ti ratios are tested and the synthesis is adapted for each dopant. For urea- and trimethylamine-doped samples, anatase-brookite TiO2 nanoparticles of 6–8 nm are formed, with a specific surface area between 200 and 275 m2 g−1. In ethylenediamine-doped samples, the formation of rutile phase is observed, and TiO2 nanoparticles of 6–8 nm with a specific surface area between 185 and 240 m2 g−1 are obtained. X-ray photoelectron spectroscopy (XPS) and diffuse reflectance measurements show the incorporation of nitrogen in TiO2 materials through Ti–O–N bonds allowing light absorption in the visible region. Photocatalytic tests on the remediation of water polluted with p-nitrophenol show a marked improvement for all doped catalysts under visible light. The optimum doping, taking into account cost, activity and ease of synthesis, is up-scaled to a volume of 5 L and compared to commercial Degussa P25 material. This up-scaled sample shows similar properties compared to the lab-scale sample, i.e., a photoactivity 4 times higher than commercial P25. [less ▲]

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See detailSpray-coating as a scalable means for making TiO2 thin films in the context of advanced oxidative processes
Wolfs, Cédric ULiege; Mahy, Julien ULiege; Mertes, Alexander ULiege et al

Conference (2018, October 29)

Micropollutants are introduced into the environment by domestic, industrial or hospital waste waters. TiO2 photocatalysis is an efficient and versatile way of removal of these micropollutants. However ... [more ▼]

Micropollutants are introduced into the environment by domestic, industrial or hospital waste waters. TiO2 photocatalysis is an efficient and versatile way of removal of these micropollutants. However, efficient, low-cost production of TiO2 thin films is not straightforward in the case of big reactors. Spray-coating is presented as the better solution cost-wise, and as a similar solution efficiency-wise. [less ▲]

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See detailOptimization of calcium phosphate ceramic
Tilkin, Rémi ULiege; Regibeau, Nicolas ULiege; Grandfils, Christian ULiege et al

Poster (2018, October 29)

During the past few years, tissue engineering has become one of the most promising techniques to maintain, improve, or reconstruct human tissue, even complete human organs. This solution is frequently ... [more ▼]

During the past few years, tissue engineering has become one of the most promising techniques to maintain, improve, or reconstruct human tissue, even complete human organs. This solution is frequently based on the realization of temporary porous matrices, also called "scaffolds". These materials are highly porous matrices designed to structure the development of cells, but also to guarantee the function of the implant during the regeneration process. Several materials have been proposed for the conception of scaffolds, including calcium phosphate ceramics. Among these materials, the bioceramic class is composed of hydroxyapatite (HA), Ca5(PO4)3(OH), and β-tricalcium phosphate (TCP), β-Ca3(PO4)2. These two products are frequently used, because of their chemical and structural similarity to human bones. These similarities explain good scores observed in vitro and in vivo in terms of biocompatibility and cell colonization. [less ▲]

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See detailEfficient P/N and Ag-doped titania for the photocatalytic degradation of waste water organic pollutants
Mahy, Julien ULiege; Bodson, Céline; Cerfontaine, Vincent et al

Conference (2018, October 04)

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See detailDiseño y Simulación de un Reactor de Reformado Catalítico de Lecho Fijo para Obtener Gas de Síntesis a partir de Glicerol
Solis Garcia, Hugo Fernando ULiege; Manosalvas, Jhonattan; De la Rosa, Andrés et al

Poster (2018, August 03)

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See detailCatalytic reforming of biomass gasification tars with bimetallic catalysts
Claude, Vincent; Solis Garcia, Hugo Fernando ULiege; Geens, Jérémy ULiege et al

Poster (2018, July 11)

The thermochemical method called “biomass gasification” is generating emphatic interest for the production of bio-Syngas (CO + H2) since this process presents the advantage of being renewable without ... [more ▼]

The thermochemical method called “biomass gasification” is generating emphatic interest for the production of bio-Syngas (CO + H2) since this process presents the advantage of being renewable without emitting CO2. However, in practical applications, there are still some technical problems due to high tars concentration in the outlet gas which can condensate and clog the pipes. The objectives of this project is to synthesize, characterize and evaluate the catalytic performances of Ni/γ-Al2O3 catalysts doped with different metals (Cu, Co, Mo, Mn, Fe). [less ▲]

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See detailAdvanced oxidative treatment for wastewater contaminated by micropollutants
Wolfs, Cédric ULiege; Belet, Artium ULiege; Mertes, Alexander ULiege et al

Poster (2018, July 09)

Micropollutants are introduced into the environment by domestic, industrial or hospital waste waters. Some of them are poorly removed by classical waste water treatment plants. The project plans to ... [more ▼]

Micropollutants are introduced into the environment by domestic, industrial or hospital waste waters. Some of them are poorly removed by classical waste water treatment plants. The project plans to develop an efficient and versatile oxidative method of removal of these micropollutants inside a waste water treatment plant (WWTP). The main technique developed is photocatalysis, where a material causes chemical reactions when exposed to light. [less ▲]

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See detailAdvanced oxidative treatment for wastewater contaminated by micropollutants
Wolfs, Cédric ULiege; Vreuls, Christelle ULiege; Mertes, Alexander et al

Poster (2018, June 19)

Micropollutants are introduced into the environment by domestic, industrial or hospital waste waters. Some of them are poorly removed by classical waste water treatment plants. The project plans to ... [more ▼]

Micropollutants are introduced into the environment by domestic, industrial or hospital waste waters. Some of them are poorly removed by classical waste water treatment plants. The project plans to develop an efficient and versatile oxidative method of removal of these micropollutants inside a waste water treatment plant (WWTP). [less ▲]

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See detailSynthesis of bimetallic catalysts supported on alumina by an aqueous sol-gel process
Lambert, Stéphanie ULiege

Conference (2018, February 20)

The thermochemical method called “biomass gasification” is generating emphatic interest for the production of bio-Syngas (CO+H2) since this process presents the advantage of being renewable without ... [more ▼]

The thermochemical method called “biomass gasification” is generating emphatic interest for the production of bio-Syngas (CO+H2) since this process presents the advantage of being renewable without emitting CO2. However, in practical applications, there are still some technical problems due to high concentration of tars in the outlet gas, which can condensate and clog the pipes. Previous studies have highlighted the fact that the tar elimination via catalytic reforming seem to be the more practical and economical solution. Catalysts were synthesized by an aqueous sol-gel process to develop γ-Al2O3 doped with 10 wt.% of nickel and 2 wt.% of a second dopant (Co, Cu, Fe, Mn, Mo). Before their adding in AlOOH sol, metallic dopants were complexed with (OCH3)3-Si-(CH2)3-NH-(CH2)2-NH2 (EDAS) to increase their dispersion by cogelation between EDAS and AlOOH clusters. All the samples were tested for toluene reforming at 650°C for 300 min. No previous reduction step has been realized. Each 15 min, injection was sent to a GC Compac for analysis. For samples Al2O3-10Ni-2Mn and Al2O3-10Ni-2Mo, the addition of Mn or Mo allows increasing the toluene conversion up to 100%, whereas all other samples present lower toluene conversion (around 30%). Taking into account the benzene selectivity, it is observed that Mn and Mo are both elements that favor the degradation of aromatic groups. In term of carbon deposit during catalytic test, sample Al2O3-10Ni-2Mn is the most interesting doping since only 0.04 gcarbon gcata-1 is depicted by TG-DSC measurement after catalytic test. [less ▲]

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