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Articoli di riviste sul tema "Catalyseur de surface"

Autore: Grafiati

Pubblicato: 19 ottobre 2023

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1

Zalma, Roger, Lionel Bonneau, Jeanine Fournier, Joëlle Guignard, Françoise Borg e Henri Pezerat. "Hydrodésazotation de l'indole sur catalyseur fer supporté sur amiante". Canadian Journal of Chemistry 65, n. 3 (1 marzo 1987): 523–27. http://dx.doi.org/10.1139/v87-091.

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The aim of this study is to examine hydrodenitrogenation (HDN) of indole on asbestos catalysts (chrysotile and crocidolite) under hydrogen pressure. HDN is carried out according to two competitive pathways, either via ortho-ethylaniline or via ortho-toluidine. This reaction is assisted by increase of temperature and pressure and by pre-reduction of the asbestos. Particles of Fe0on the fibre surface are formed from the original material. Their presence plays a role in the initial breaking of the C—N bond and in the hydrogenation reaction.

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2

Merabet, Smail, Abdelkrim Bouzaza, Mohamed Bouhelassa e Dominique Wolbert. "Modélisation et optimisation de la photodégradation du 4-méthylphénol dans un réacteur à recirculation en présence d’UV/ZnO". Revue des sciences de l'eau 22, n. 4 (22 ottobre 2009): 565–73. http://dx.doi.org/10.7202/038331ar.

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Résumé L’étude de la photodégradation du 4-méthylphénol a été menée sur un pilote à recirculation. Cette molécule a été prise comme composé modèle pour le traitement des effluents de l’industrie avicole. Ce travail a consisté en l’optimisation et la modélisation de l’élimination du 4-méthylphénol par photocatalyse en présence de ZnO. L’utilisation des plans d’expériences, et en particulier de la méthodologie de surface de réponse (RSM) et un plan central composite (CCD), a permis la détermination de l’influence des effets simultanés et de l’interaction des paramètres opératoires sur le rendement de la photodégradation. Les paramètres étudiés sont la concentration initiale en 4-méthylphénol, la concentration en catalyseur et le débit de recirculation de la solution. Les résultats montrent que l’application de la RSM permet de décrire d’une manière correcte l’influence de ces trois paramètres expérimentaux sur l’efficacité du traitement. Les valeurs optimales des paramètres donnant un rendement maximal (100 %) ont pu être déterminées. Les modèles de second ordre obtenus, pour le rendement de dégradation et pour l’abattement de DCO, ont été validés en utilisant différentes approches statistiques. L’utilisation de la méthode ANOVA a montré que les modèles sont hautement significatifs et en bonne adéquation avec les résultats expérimentaux.

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Hurren, C. J., R. T. Liu, Xin Liu e X. G. Wang. "Photo-Catalysis of Red Wine Stains Using Titanium Dioxide Sol-Gel Coatings on Wool Fabrics". Advances in Science and Technology 60 (settembre 2008): 111–16. http://dx.doi.org/10.4028/www.scientific.net/ast.60.111.

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This paper investigated the use of titanium dioxide sol-gel coatings to photo-catalyse red wine stains on wool fabrics. Coatings were produced by the hydrolysis and condensation of titanium butoxide (Ti(OC4H9)4) on the surface of wool fabrics after pad application. Coatings were partially converted to the anatase form of titanium dioxide by prolonged immersion in boiling water. The coating presence was confirmed using scanning electron microscopy, UVspectrophotometry and atomic force microscopy. Coated samples were measured for photo-catalytic activity by degrading red wine stains from the surface of the coated fabric. The level of photocatalysis was determined for each of the coating systems after 168 hours. Red wine stains were photo-catalysed and level of staining was reduced from the UV exposed surface of the coated wool fabric.

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4

Bergel, Alain. "Recent Advances in Electron Transfer Between Biofilms and Metals". Advanced Materials Research 20-21 (luglio 2007): 329–34. http://dx.doi.org/10.4028/www.scientific.net/amr.20-21.329.

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Microbial biofilms produce electrochemical interactions with metal surfaces by following a wide variety of different electron exchange pathways. Reviewing the mechanisms identified in the biocorrosion of steels leads us to distinguish direct and indirect mechanisms for biofilm-catalysed cathodic reactions. Indirect mechanisms are due to the production of metal oxides or hydrogen peroxide (aerobic corrosion) or metal sulphides (anaerobic corrosion), which further react with the metal surface. Direct mechanisms involve adsorbed biocompounds, generally enzymes or their active sites, which catalyse the cathodic reduction of oxygen for aerobic biocorrosion or the proton/water reduction in anaerobic processes. Recent studies dealing with the role of hydrogenases in anaerobic corrosion have shed light on the important role of phosphate species via so-called cathodic deprotonation. Advances in the development of microbial fuel cells have also resulted in new concepts, mainly for oxidation processes. Some microbial cells have been shown to be able to produce their own electron mediators. Others can transfer electrons directly to electrodes through membrane-bound electron shuttles or achieve long-range transfer through conductive pili.

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5

Mozaceanu, Cristina, Christopher G. P. Taylor, Jerico R. Piper, Stephen P. Argent e Michael D. Ward. "Catalysis of an Aldol Condensation Using a Coordination Cage". Chemistry 2, n. 1 (25 gennaio 2020): 22–32. http://dx.doi.org/10.3390/chemistry2010004.

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The aldol condensation of indane-1,3-dione (ID) to give ‘bindone’ in water is catalysed by an M8L12 cubic coordination cage (Hw). The absolute rate of reaction is slow under weakly acidic conditions (pH 3–4), but in the absence of a catalyst it is undetectable. In water, the binding constant of ID in the cavity of Hw is ca. 2.4 (±1.2) × 103 M−1, giving a ∆G for the binding of −19.3 (±1.2) kJ mol−1. The crystal structure of the complex revealed the presence of two molecules of the guest ID stacked inside the cavity, giving a packing coefficient of 74% as well as another molecule hydrogen-bonded to the cage’s exterior surface. We suggest that the catalysis occurs due to the stabilisation of the enolate anion of ID by the 16+ surface of the cage, which also attracts molecules of neutral ID to the surface because of its hydrophobicity. The cage, therefore, brings together neutral ID and its enolate anion via two different interactions to catalyse the reaction, which—as the control experiments show—occurs at the exterior surface of the cage and not inside the cage cavity.

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Wong, W.-Y., S. Lim, Y.-L. Pang, C.-H. Lim, F.-L. Pua e G. Pua. "Response surface optimisation of biodiesel synthesis using biomass derived green heterogeneous catalyst". IOP Conference Series: Materials Science and Engineering 1257, n. 1 (1 ottobre 2022): 012010. http://dx.doi.org/10.1088/1757-899x/1257/1/012010.

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Abstract Although homogeneous alkali-catalysed transesterification is the typical process used in biodiesel production, it caused complications in downstream separation processes and an oversupply of glycerol as a by-product. The present work studied the synthesis of a novel sulfonated biomass-derived solid acid catalyst and its application in biodiesel production via interesterification of oleic acid. Solid acid catalysts were prepared by direct sulfonation via thermal treatment with concentrated sulfuric acid. The design of experiments was conducted via four-factors central composite design (CCD) coupled with response surface methodology (RSM) analysis. The parameters considered for optimisation included carbonisation and sulfonation temperatures, catalyst loading and reaction time, each varied at five levels. The maximum yield of fatty acid methyl ester (FAME) was obtained using optimum parameters as carbonisation temperature of 586 °C, sulfonation temperature of 110 °C, catalyst loading of 10.5 wt.% and reaction time of 7 h was 54.3 % based on the theoretical ester formation. A quadratic mathematical model in RSM was successfully established that can make effective predictions about the anticipated biodiesel yield. This study proved that the low-cost heterogeneous catalyst derived from biomass waste with a simple production route could catalyse the interesterification process under moderate process conditions.

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7

Papageorgiou, G., J. D. Major e K. Durose. "Substrate geometry CdTe solar cells with catalytically-grown nano-rough surfaces". MRS Advances 1, n. 14 (2016): 985–90. http://dx.doi.org/10.1557/adv.2016.153.

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ABSTRACTSubstrate geometry CdTe solar cells have been modified with the addition of metal-catalysed nano-structures in order to influence their efficiency. Conditions for the growth of Au- and Bi-catalysed nanostructures were explored. The substrate devices themselves comprised indium tin oxide/CdS/CdTe/Mo foil and were developed using the MgCl2 alternative to the usual CdCl2 processing – this yielded open circuit voltages of up to 740 mV. It was demonstrated that the addition of Au-catalysed nanowires to 200 nm thick CdTe films on glass substrates decreased their optical transmission by 10%, this being significantly higher than for thick films. However, reproducibility issues with forming Bi nanostructures limited the device modification tests to the use of Au-catalysed wires, and these always acted to depress photovoltaic performance.

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8

Tsuji, Hideto, e Hideshi Hattori. "Oxide Surfaces that Catalyse an Acid–Base Reaction with Surface Lattice Oxygen Exchange: Evidence of Nucleophilicity of Oxide Surfaces". ChemPhysChem 5, n. 5 (17 maggio 2004): 733–36. http://dx.doi.org/10.1002/cphc.200400009.

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9

Chen, L., F. Qi, B. Xu, Z. Xu, J. Shen e K. Li. "The efficiency and mechanism of γ-alumina catalytic ozonation of 2-methylisoborneol in drinking water". Water Supply 6, n. 3 (1 luglio 2006): 43–51. http://dx.doi.org/10.2166/ws.2006.726.

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The efficiency and mechanism in degradation of 2-methylisoborneol (MIB) as a taste and odour compound in drinking water were studied under the condition where γ-alumina catalysed ozonation. As a result, γ-alumina can show distinct activity in enhancing the efficiency of ozonation of MIB. Tert-butyl alcohol had a remarkable effect on the removal efficiency of catalytic ozonation of MIB. The surface charge status, surface hydroxyl group status of γ-alumina, and pH values of the solution can be linked together. When the pH value of the solution was near the pHzpc of γ-Al2O3, there was observable activity in the catalysed ozonation process. Rct, which denoted the relative concentration of hydroxyl radical (·OH), was much higher in the catalysed ozonation process than in the ozonation process. This result further illuminated that γ-Al2O3 can promote ozone decomposition to produce ·OH. Finally, the effect of rP/I on catalysed ozone decomposition and ozone decomposition was investigated.

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10

Wang, Dianzhan, Ye Gu, Zhaoshun Yang e Lixiang Zhou. "Synthesis and assessment of schwertmannite/few-layer graphene composite for the degradation of sulfamethazine in heterogeneous Fenton-like reaction". Royal Society Open Science 7, n. 7 (luglio 2020): 191977. http://dx.doi.org/10.1098/rsos.191977.

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Schwertmannite (sch), an iron oxyhydrosulfate mineral, can catalyse a Fenton-like reaction to degrade organic contaminants, but the reduction of Fe(III) to Fe(II) on the surface of schwertmannite is a limiting step for the Fenton-like process. In the present study, the sch/few-layer graphene (sch–FLG) composite was synthesized to promote the catalytic activity of sch in a Fenton-like reaction. It was found that sch can be successfully carried by FLG in sch–FLG composite, mainly via the chemical bond of Fe–O–C on the surface of sch–FLG. The sch–FLG exhibited a much higher catalytic activity than sch or FLG for the degradation of sulfamethazine (SMT) in the heterogeneous Fenton-like reaction, which resulted from the fact that the FLG can pass electrons efficiently. The degradation efficiency of SMT was around 100% under the reaction conditions of H 2 O 2 200–500 mg l −1 , sch–FLG dosage 1–2 g l −1 , temperature 28–38°C, and initial solution pH 1–9. During the repeated uses of sch–FLG in the Fenton-like reaction, it maintained a certain catalytic activity for the degradation of SMT and the mineral structure was not changed. In addition, SMT may be finally mineralized in the Fenton-like reaction catalysed by sch–FLG, and the possible degradation pathways were proposed. Therefore, the sch–FLG is an excellent catalyst for SMT degradation in a heterogeneous Fenton-like reaction.

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Bedford, Monte S., Xiaoyan Yang, Kara M. Jolly, Rachel L. Binnicker, Samuel B. Cramer, Caitlin E. Keen, Connor J. Mairena et al. "Tetraarylphosphonium polyelectrolyte chromophores: synthesis, stability, photophysics, film morphology and critical surface energy". Polymer Chemistry 6, n. 6 (2015): 900–908. http://dx.doi.org/10.1039/c4py01483a.

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12

Otero, Gonzalo, Giulio Biddau, Carlos Sánchez-Sánchez, Renaud Caillard, María F. López, Celia Rogero, F. Javier Palomares et al. "Fullerenes from aromatic precursors by surface-catalysed cyclodehydrogenation". Nature 454, n. 7206 (agosto 2008): 865–68. http://dx.doi.org/10.1038/nature07193.

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13

Wood, CaldweII, Evans, Jones, Korber, Wolfhaardt, Wilson e Gilbert. "Surface-catalysed disinfection of thick Pseudomonas aeruginosa biofilms". Journal of Applied Microbiology 84, n. 6 (giugno 1998): 1092–98. http://dx.doi.org/10.1046/j.1365-2672.1998.00446.x.

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14

Schneider, E. M., M. Zeltner, N. Kränzlin, R. N. Grass e W. J. Stark. "Base-free Knoevenagel condensation catalyzed by copper metal surfaces". Chemical Communications 51, n. 53 (2015): 10695–98. http://dx.doi.org/10.1039/c5cc02541a.

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15

Chen, Chunping, Maxwell Greenwood, Jean-Charles Buffet e Dermot O'Hare. "Aqueous miscible organic layered double hydroxides as catalyst precursors for biodiesel synthesis". Green Chemistry 22, n. 10 (2020): 3117–21. http://dx.doi.org/10.1039/d0gc00571a.

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Quesada, Jorge, Laura Faba, Eva Díaz e Salvador Ordóñez. "Effect of catalyst morphology and hydrogen co-feeding on the acid-catalysed transformation of acetone into mesitylene". Catalysis Science & Technology 10, n. 5 (2020): 1356–67. http://dx.doi.org/10.1039/c9cy02288k.

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17

Liu, Yansheng, Xinlin Li, Xuanduong Le, Wei Zhang, Hao Gu, Ruiwen Xue e Jiantai Ma. "Catalysis of the hydro-dechlorination of 4-chlorophenol by Pd(0)-modified MCM-48 mesoporous microspheres with an ultra-high surface area". New Journal of Chemistry 39, n. 6 (2015): 4519–25. http://dx.doi.org/10.1039/c5nj00617a.

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Hultquist, G., e P. Szakálos. "Catalysed self-cleaning of air on the earth's surface". Journal of Atmospheric Chemistry 55, n. 2 (15 agosto 2006): 131–46. http://dx.doi.org/10.1007/s10874-006-9031-0.

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19

Hu, Yingxue, Joshua B. Marlow, Rajesh Ramanathan, Wenyue Zou, Hui Geok Tiew, Matthew J. Pottage, Vipul Bansal, Rico F. Tabor e Brendan L. Wilkinson. "Synthesis and Properties of Photoswitchable Carbohydrate Fluorosurfactants". Australian Journal of Chemistry 68, n. 12 (2015): 1880. http://dx.doi.org/10.1071/ch15434.

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We describe the parallel synthesis, photocontrollable surface tension, and antibacterial performance of a new class of carbohydrate fluorosurfactant. Novel fluorosurfactants comprised a mono- or disaccharide head group linked to an azobenzene unit that was variably substituted with a trifluoromethyl group. Fluorosurfactants were rapidly assembled using the venerable CuI-catalysed azide–alkyne cycloaddition reaction and exhibited light-addressable surface activity, excellent water solubility, and selective antibacterial activity against Gram-positive Staphylococcus aureus. Notably, the physicochemical and biological activity of these novel materials was heavily dependent on the nature of the head group and the position of the trifluoromethyl substituent on the azobenzene ring. The UV-adapted cis-isomer of fluorosurfactants displayed good thermal stability at ambient temperature, with little reversion to the stable trans isomer after 16 h. These novel, light-responsive materials should find broad interest in a range of biomedical and technological fields, including drug and gene delivery, self-cleaning oleophobic surfaces, and antibacterial coatings for medical devices.

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Poznik, M., e B. König. "Cooperative hydrolysis of aryl esters on functionalized membrane surfaces and in micellar solutions". Org. Biomol. Chem. 12, n. 20 (2014): 3175–80. http://dx.doi.org/10.1039/c4ob00247d.

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Taoufik, M., C. Santini, JM Basset e JP Candy. "Greffage de dérivés chiraux du germanium sur des surfaces métalliques. Génèse de catalyseurs hétérogènes asymétriques par voie chimie organométallique de surface". Journal de Chimie Physique 94 (1997): 1969–74. http://dx.doi.org/10.1051/jcp/1997941969.

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Maronna, M. M., E. C. Kruissink, R. F. Parton, F. Soulimani, B. M. Weckhuysen e W. F. Hoelderich. "Spectroscopic study on the active site of a SiO2 supported niobia catalyst used for the gas-phase Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam". Physical Chemistry Chemical Physics 18, n. 32 (2016): 22636–46. http://dx.doi.org/10.1039/c6cp03014a.

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Qin, Yangzhong, Benjamin C. M. Martindale, Rui Sun, Adam J. Rieth e Daniel G. Nocera. "Solar-driven tandem photoredox nickel-catalysed cross-coupling using modified carbon nitride". Chemical Science 11, n. 28 (2020): 7456–61. http://dx.doi.org/10.1039/d0sc02131h.

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Nickel-catalysed aryl amination and etherification are driven with sunlight using a surface-modified carbon nitride to extend the absorption of the photocatalyst such that they may be driven with solar light.

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Miran, Hussein A., Mohammednoor Altarawneh, Zainab N. Jaf, M. Mahbubur Rahman, Mansour H. Almatarneh e Zhong-Tao Jiang. "Influence of the variation in the Hubbard parameter (U) on activation energies of CeO2-catalysed reactions". Canadian Journal of Physics 98, n. 4 (aprile 2020): 385–89. http://dx.doi.org/10.1139/cjp-2019-0065.

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Accurate description of thermodynamic, structural, and electronic properties for bulk and surfaces of ceria (CeO2) necessitates the inclusion of the Hubbard parameter (U) in the density functional theory (DFT) calculations to precisely account for the strongly correlated 4f electrons. Such treatment is a daunting task when attempting to draw a potential energy surface for CeO2-catalyzed reaction. This is due to the inconsistent change in thermo-kinetics parameters of the reaction in reference to the variation in the U values. As an illustrative example, we investigate herein the discrepancy in activation and reaction energies for steps underlying the partial and full hydrogenation of acetylene over the CeO2(111) surface. Overall, we find that both activation and reaction energies positively correlate with the increase in the U value. In addition to benchmarking against more accurate theoretical methodologies, we suggest that U values are better optimized against kinetics modelling of experimentally observed profiles of products from the catalytic-assisted system of reactions.

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Visser, Anna-Neva, Scott D. Wankel, Pascal A. Niklaus, James M. Byrne, Andreas A. Kappler e Moritz F. Lehmann. "Impact of reactive surfaces on the abiotic reaction between nitrite and ferrous iron and associated nitrogen and oxygen isotope dynamics". Biogeosciences 17, n. 16 (28 agosto 2020): 4355–74. http://dx.doi.org/10.5194/bg-17-4355-2020.

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Abstract. Anaerobic nitrate-dependent Fe(II) oxidation (NDFeO) is widespread in various aquatic environments and plays a major role in iron and nitrogen redox dynamics. However, evidence for truly enzymatic, autotrophic NDFeO remains limited, with alternative explanations involving the coupling of heterotrophic denitrification with the abiotic oxidation of structurally bound or aqueous Fe(II) by reactive intermediate nitrogen (N) species (chemodenitrification). The extent to which chemodenitrification is caused (or enhanced) by ex vivo surface catalytic effects has not been directly tested to date. To determine whether the presence of either an Fe(II)-bearing mineral or dead biomass (DB) catalyses chemodenitrification, two different sets of anoxic batch experiments were conducted: 2 mM Fe(II) was added to a low-phosphate medium, resulting in the precipitation of vivianite (Fe3(PO4)2), to which 2 mM nitrite (NO2-) was later added, with or without an autoclaved cell suspension (∼1.96×108 cells mL−1) of Shewanella oneidensis MR-1. Concentrations of nitrite (NO2-), nitrous oxide (N2O), and iron (Fe2+, Fetot) were monitored over time in both set-ups to assess the impact of Fe(II) minerals and/or DB as catalysts of chemodenitrification. In addition, the natural-abundance isotope ratios of NO2- and N2O (δ15N and δ18O) were analysed to constrain the associated isotope effects. Up to 90 % of the Fe(II) was oxidized in the presence of DB, whereas only ∼65 % of the Fe(II) was oxidized under mineral-only conditions, suggesting an overall lower reactivity of the mineral-only set-up. Similarly, the average NO2- reduction rate in the mineral-only experiments (0.004±0.003 mmol L−1 d−1) was much lower than in the experiments with both mineral and DB (0.053±0.013 mmol L−1 d−1), as was N2O production (204.02±60.29 nmol L−1 d−1). The N2O yield per mole NO2- reduced was higher in the mineral-only set-ups (4 %) than in the experiments with DB (1 %), suggesting the catalysis-dependent differential formation of NO. N-NO2- isotope ratio measurements indicated a clear difference between both experimental conditions: in contrast to the marked 15N isotope enrichment during active NO2- reduction (15εNO2=+10.3 ‰) observed in the presence of DB, NO2- loss in the mineral-only experiments exhibited only a small N isotope effect (<+1 ‰). The NO2--O isotope effect was very low in both set-ups (18εNO2 <1 ‰), which was most likely due to substantial O isotope exchange with ambient water. Moreover, under low-turnover conditions (i.e. in the mineral-only experiments as well as initially in experiments with DB), the observed NO2- isotope systematics suggest, transiently, a small inverse isotope effect (i.e. decreasing NO2- δ15N and δ18O with decreasing concentrations), which was possibly related to transitory surface complexation mechanisms. Site preference (SP) of the 15N isotopes in the linear N2O molecule for both set-ups ranged between 0 ‰ and 14 ‰, which was notably lower than the values previously reported for chemodenitrification. Our results imply that chemodenitrification is dependent on the available reactive surfaces and that the NO2- (rather than the N2O) isotope signatures may be useful for distinguishing between chemodenitrification catalysed by minerals, chemodenitrification catalysed by dead microbial biomass, and possibly true enzymatic NDFeO.

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Pantaleone, Stefano, Clara Salvini, Lorenzo Zamirri, Matteo Signorile, Francesca Bonino e Piero Ugliengo. "A quantum mechanical study of dehydration vs. decarbonylation of formamide catalysed by amorphous silica surfaces". Physical Chemistry Chemical Physics 22, n. 16 (2020): 8353–63. http://dx.doi.org/10.1039/d0cp00572j.

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Ludden, Michael D., Christopher G. P. Taylor, Max B. Tipping, Jennifer S. Train, Nicholas H. Williams, Jack C. Dorrat, Kellie L. Tuck e Michael D. Ward. "Interaction of anions with the surface of a coordination cage in aqueous solution probed by their effect on a cage-catalysed Kemp elimination". Chemical Science 12, n. 44 (2021): 14781–91. http://dx.doi.org/10.1039/d1sc04887b.

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A cage-catalysed Kemp elimination reaction of 5-nitro-1,2-benzisoxazole (NBI) with hydroxide to give 2-cyano-4-nitrophenolate (CNP) as the product is sensitive to binding of different types of anion to the cage surface.

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Weiss, Karin, e Kurt Hoffmann. "Untersuchungen von Polymerisations-und Metathesereaktionen, X. Mitt. [1] Polymerisation, Trimerisation und Metathese von Allenen und Heteroallenen mit reduziertem Phillips-Katalysator / Studies of Polymerisation and Metathesis Reactions, Part X [1] Polymerisation, Trimerisation and Metathesis of Allenes and Heteroallenes with Reduced Phillips Catalyst". Zeitschrift für Naturforschung B 42, n. 6 (1 giugno 1987): 769–73. http://dx.doi.org/10.1515/znb-1987-0621.

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Abstract The reduced Phillips Catalyst - a surface chromium(II) on silica - catalyses the polymerisation of the allene 1,2-butadiene to yield predominantly 1,2-polybutadiene, yields trimerisation products with isocyanates, and gives metathesis of 2 differently substituted carbodiimides.

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Alonso, Rafael, Pilar Jiménez-Meneses, Jaime García-Rupérez, María-José Bañuls e Ángel Maquieira. "Thiol–ene click chemistry towards easy microarraying of half-antibodies". Chemical Communications 54, n. 48 (2018): 6144–47. http://dx.doi.org/10.1039/c8cc01369a.

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Makrovic, V. Lj, M. M. Pejovic e Z. Lj Petrovic. "Explanation of memory curve for nitrogen by surface-catalysed excitation". Journal of Physics D: Applied Physics 26, n. 10 (14 ottobre 1993): 1611–13. http://dx.doi.org/10.1088/0022-3727/26/10/011.

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Basu, Basudeb, Satadru Jha, Niranjan K. Mridha e Md Mosharef H. Bhuiyan. "Palladium-catalysed amination of halopyridines on a KF-alumina surface". Tetrahedron Letters 43, n. 44 (ottobre 2002): 7967–69. http://dx.doi.org/10.1016/s0040-4039(02)01852-x.

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HAMADA, Kazuhiko, Hiroshi YOSHIHARA e Gohfu SUZUKAMO. "Surface Active Agent-Catalysed Conversion of Saccharides to Furfural Derivatives." Journal of Oleo Science 50, n. 3 (2001): 207–9. http://dx.doi.org/10.5650/jos.50.207.

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Taylor, Christopher G. P., Alexander J. Metherell, Stephen P. Argent, Fatma M. Ashour, Nicholas H. Williams e Michael D. Ward. "Coordination‐Cage‐Catalysed Hydrolysis of Organophosphates: Cavity‐ or Surface‐Based?" Chemistry – A European Journal 26, n. 14 (6 febbraio 2020): 3065–73. http://dx.doi.org/10.1002/chem.201904708.

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34

Ishitsuka, Takuya, Yasuhiro Okuda, Robert K. Szilagyi, Seiji Mori e Yasushi Nishihara. "The molecular mechanism of palladium-catalysed cyanoesterification of methyl cyanoformate onto norbornene". Dalton Transactions 45, n. 18 (2016): 7786–93. http://dx.doi.org/10.1039/c6dt00341a.

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Abstract (sommario):

Density functional theory-based potential energy surface investigation revealed that the reaction mechanism of palladium-catalysed cyanoesterification onto norbornene (NBE) proceeds through exclusive exo-coordination, regioselective olefin insertion first into the Pd–COOR bond, and reduction elimination to form the subsituted NBE.

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35

van Heerde, W. L., S. Poort, C. van 't Veer, C. P. M. Reutelingsperger e P. G. de Groot. "Binding of recombinant annexin V to endothelial cells: effect of annexin V binding on endothelial-cell-mediated thrombin formation". Biochemical Journal 302, n. 1 (15 agosto 1994): 305–12. http://dx.doi.org/10.1042/bj3020305.

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Abstract (sommario):

Annexin V binds with high affinity to procoagulant phospholipid vesicles and thereby inhibits the procoagulant reactions catalysed by these surfaces in vitro. In vivo, vascular endothelial cells are known to catalyse the formation of thrombin by the expression of binding sites at which procoagulant complexes can assemble. Here, we have studied the binding capacity of recombinant annexin V (rANV) to quiescent, phorbol 12-myristate 13-acetate (PMA)- and tumour necrosis factor alpha (TNF-alpha)-stimulated cultured human umbilical-vein endothelial cells (HUVEC). The dissociation constant (Kd) was 15.5 +/- 3.3 nM and the number of binding sites was 8.8 (+/- 3.9) x 10(6)/cell. These binding parameters did not change significantly during a 30 h incubation period with PMA or TNF-alpha. rANV inhibited HUVEC-mediated factor Xa formation via the extrinsic as well as the intrinsic route. Activation of factor X by the tissue factor-factor VII-factor X complex and tenase complex was inhibited with IC50 values of 43 +/- 30 nM and 33 +/- 24 nM respectively. Endothelial-cell-mediated generation of thrombin by the prothrombinase complex was inhibited by rANV with an IC50 of 16 +/- 12 nM. Preincubation of rANV with the endothelial cells did not significantly influence the IC50 values. These results show that rANV binds to the same extent to quiescent, PMA- and TNF-stimulated HUVEC, and, as a result of this binding, rANV efficiently inhibits endothelial-cell-mediated thrombin formation.

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36

Sallam, Lamyaa M., Tze Chieh Shiao, Celia Sehad, Abdelkrim Azzouz e René Roy. "Accelerated Synthesis of Surface Functionalized Mannosylated Dendrimers Built on Cyclotriphosphazene Core". MRS Advances 4, n. 59-60 (2019): 3187–98. http://dx.doi.org/10.1557/adv.2019.375.

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ABSTRACTThe syntheses of five propargylated dendrimer scaffolds ranging from 2, 3, 4, 6, and 12 surface groups are described together with a 2-azidoethyl α-D-mannopyranoside. The former is appended to the core structure using highly efficient copper-catalysed azide-alkyne cycloaddition (CuAAC) (“click reaction”) to provide glycodendrimers in an accelerated approach. Two of the core structures are based on cyclotrisphosphazene, thus expanding the scope of the “onion-peel” strategy to build dendritic architectures with a large number of surface groups at the G1 generation only.

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Jiménez-Morales, Ignacio, Sara Cavaliere, Marc Dupont, Deborah Jones e Jacques Rozière. "On the stability of antimony doped tin oxide supports in proton exchange membrane fuel cell and water electrolysers". Sustainable Energy & Fuels 3, n. 6 (2019): 1526–35. http://dx.doi.org/10.1039/c8se00619a.

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This study on bare and catalysed Sb–SnO₂ electrospun tubes allowed to determine the potential window for its optimal utilisation as electrocatalyst support in PEM fuel cells and water electrolysers: the stability of the oxide strongly depends on the existing surface segregation of Sb.

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38

Ghindilis, A. "Direct electron transfer catalysed by enzymes: application for biosensor development". Biochemical Society Transactions 28, n. 2 (1 febbraio 2000): 84–89. http://dx.doi.org/10.1042/bst0280084.

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Abstract (sommario):

The ability to catalyse an electrode reaction via direct (mediatorless) electron transfer has been demonstrated for a number of redox enzymes. In the case of mediatorless electron transfer, the electron is transferred directly from the electrode to the substrate molecule via the active site of the enzyme, or vice versa. The electron itself is the second substrate for the reaction. An important point characterizing bioelectrocatalysis is the catalytic removal of the reaction over-voltage. Therefore the enzyme attached to the electrode is able to catalyse electrode reaction and forms a ‘molecular transducer’. The substrate can be detected by potentiometric measurement of the removal of reaction over-voltage. The enzyme laccase is able to catalyse the reaction of oxygen electroreduction. Therefore a laccase molecular layer attached to the electrode surface forms an oxygen transducer. The formation of the layer results in a change of the electrocatalytic feature of the electrode. Laccase label coupled with either ligand or receptor allows the detection of ligand-receptor complex formation/dissociation on the electrode surface. The detection is virtually reagentless. The substrates for the reaction are molecular oxygen and the electron itself. Numerous reagentless immunosensors of different formats (competitive, displacement and sandwich) have been developed, as well as the reagentless detection system for immunofiltration/immunochromatography.

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39

Yamamoto, Masanori, Qi Zhao, Shunsuke Goto, Yu Gu, Takaaki Toriyama, Tomokazu Yamamoto, Hirotomo Nishihara et al. "Porous nanographene formation on γ-alumina nanoparticles via transition-metal-free methane activation". Chemical Science 13, n. 11 (2022): 3140–46. http://dx.doi.org/10.1039/d1sc06578e.

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Abstract (sommario):

Oxygen vacancies on the (100) surface of γ-Al2O3 nanoparticles catalyse CH4-CVD for single-layered nanoporous graphenes with no transition metal reaction centre. The rate-limiting step is the proton transfer (PT) in the activation of CH4 on them.

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40

Molteni, Giorgio, Anna M. Ferretti, Mario Italo Trioni, Fausto Cargnoni e Alessandro Ponti. "The azide–alkyne cycloaddition catalysed by transition metal oxide nanoparticles". New Journal of Chemistry 43, n. 46 (2019): 18049–61. http://dx.doi.org/10.1039/c9nj04690a.

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Fe₃O₄, MnFe₂O₄, CoFe₂O₄, MnO, and α-MnS nanoparticles catalyse the title reaction by the ligation of the azide on the surface of the nanoparticle.

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41

Au, Chak-Tong, e M. Wyn Roberts. "The promotion of surface-catalysed reactions by gaseous additives. The role of a surface oxygen transient". Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases 83, n. 7 (1987): 2047. http://dx.doi.org/10.1039/f19878302047.

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42

Ren, Lu, Hongtao Ji, Karine Heuzé, Bruno Faure, Emilie Genin, Pierre Rousselot Pailley e Thierry Tron. "Modulation of laccase catalysed oxidations at the surface of magnetic nanoparticles". Colloids and Surfaces B: Biointerfaces 206 (ottobre 2021): 111963. http://dx.doi.org/10.1016/j.colsurfb.2021.111963.

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43

Gonawan, Fadzil Noor, Azlina Harun Kamaruddin, Mohamad Zailani Abu Bakar e Khairiah Abd Karim. "Immobilised-β-galactosidase Catalysed Conversion of Lactose on the Membrane Surface". Journal of Physical Science 29, Suppl. 1 (25 febbraio 2018): 49–56. http://dx.doi.org/10.21315/jps2018.29.s1.7.

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44

Tahir, Muhammad Nawaz, Patrick Théato, Werner E. G. Müller, Heinz C. Schröder, Alexandra Borejko, Simon Faiß, Andreas Janshoff, Joachim Huth e Wolfgang Tremel. "Formation of layered titania and zirconia catalysed by surface-bound silicatein". Chemical Communications, n. 44 (2005): 5533. http://dx.doi.org/10.1039/b510113a.

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45

Córdoba, A., A. Gómez e J. J. Luque. "Fractal structure in adsorbates in a catalysed reaction on a surface". Physica A: Statistical Mechanics and its Applications 322 (maggio 2003): 456–66. http://dx.doi.org/10.1016/s0378-4371(02)01820-4.

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46

Gunschera, J., J. R. Andersen, N. Schulz e T. Salthammer. "Surface-catalysed reactions on pollutant-removing building products for indoor use". Chemosphere 75, n. 4 (aprile 2009): 476–82. http://dx.doi.org/10.1016/j.chemosphere.2008.12.055.

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47

Oshima, Genichiro. "Solid surface-catalysed inactivation of bovine α-chymotrypsin in dilute solution". International Journal of Biological Macromolecules 11, n. 1 (febbraio 1989): 43–48. http://dx.doi.org/10.1016/0141-8130(89)90039-1.

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48

Payares, Gilberto, Diane J. McLaren, W. H. Evans e S. R. Smithers. "Changes in the surface antigen profile ofSchistosoma mansoniduring maturation from cercaria to adult worm". Parasitology 91, n. 1 (agosto 1985): 83–99. http://dx.doi.org/10.1017/s0031182000056535.

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Abstract (sommario):

Antigenic proteins on the surfaces of different developmental stages ofSchistosoma mansoniwere radio-iodinated by the lodogen-catalysed method and identified by immunoprecipitation with a panel of antisera. The sera comprised specific immune serum from mice harbouring a chronic schistosome infection or vaccinated with γ-irradiated cercariae; serum from rabbits immunized with adult schistosome tegumental outer membranes or a partially purified Mr32K glycoprotein from adult worm membranes; and a monoclonal antibody recognizing an Mr20 K antigen on the surface of schistosomula. The Mr38–32 K glycoproteins were the major antigens identified in surface-labelled cercariae and their probable association with the glycocalyx is discussed. Schistosomula transformed from cercariae either mechanically or by penetration of host skinin vitro, expressed a similar pattern of surface antigens to that identified for cercariae, but low molecular weight antigens of Mr20, 17 and 15 K were also detected. The Mr38–32 K glycoproteins, although present on newly transformed schistoso mula, were progressively replaced with time, by a single dominant glycoprotein (Mr32 K) expressing identical epitopes to those on the Mr 38–32 K complex. Moreover, the data confirm that the Mr32 K glycoprotein persists on the tegument afterin vivomaturation and is conserved, together with Mr20 and 15 K antigens, through to the adult stage. New antigens (Mr97 and 25 K) were also detected duringin vivomaturation and were present in late-stage schistosomes recovered from infected hosts. In addition, the enzyme alkaline phosphatase is expressed on the surfaces of 3-week-old liver worms as a dominant antigen (Mr65 K); this feature may be related to nutritional and/or physiological processes in the tegument of this metabolically active stage of development.

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Liu, Jian, Fei He e Ka Di Zhu. "Surface plasmonic catalysis based on molecular optomechanics". Europhysics Letters 137, n. 2 (1 gennaio 2022): 25002. http://dx.doi.org/10.1209/0295-5075/ac4d3f.

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Abstract Nowadays, researchers find that the surface plasmons can mediate some chemical reactions through the generation of the confined plasmonic field, excited electrons, and local heating effect. In this article we suggest a new surface plasmonic photocatalysis mechanism based on the molecular optomechanics which is not considered before. A reaction kinetic model was established to achieve a quantitative study of catalytic efficiency. The catalytic mechanism is not limited to a specific chemical reaction, all molecules with Raman activity can be accelerated dramatically in reaction. For molecules with different mechanical properties, the corresponding optomechanical catalytic pathway needs to be selected. We hope that this work will provide guidance for achieving strong or even ultrastrong catalyses under specific optical conditions. We further demonstrate that the optomechanical effects can also be used for the deceleration, which provides the possibility to design a highly tunable chemical reaction system. We believe that the quantum photochemistry will be further developed and widely used in future research.

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50

Guerrero Fajardo, Carlos Alberto, Yvonne N’Guyen, Claire Courson e Anne Cécile Roger. "Fe/SiO2 catalysts for the selective oxidation of methane to formaldehyde". Ingeniería e Investigación 26, n. 2 (1 maggio 2006): 37–44. http://dx.doi.org/10.15446/ing.investig.v26n2.14735.

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Abstract (sommario):

Selective oxidation of methane to formaldehyde was analysed with iron catalysts supported on silica prepared by the sol-gel method, leading to obtaining a large support surface area facilitating high dispersion of iron on silica’s amorphous surface. Seven catalysts were prepared; one of them corresponded to the silica support and another five having an iron load 0.1-0.5% in weight. Catalyst 7 (0.5% Fe in weight) was prepared with neutral pH control and had the most homogeneous characteristics since it did not present isolated iron species, corroborated by SEM and TEM analysis. The highest BET areas were 1,757 and 993 m2.g-1 for 0.5% Fe catalysts, having an average 36% microporosity and 43% mesoporosity. X-ray diffraction confirmed the catalyst’s amorphous structure. Catalytic activity was carried out with catalyser 7 at atmospheric pressure in a quartz reactor using a CH4/O2/N2=7.5/1/4 reaction mixture at 400-750°C temperature range. Reaction products were analysed by gas chromatography with TCD. The heterogeneous catalysts displayed greater methane conversion (but with methanol selectivity) whereas homogenous catalyst 7 gave better results regarding formaldehyde. The highest conversion percentage (8.60% mol) for catalyser 7 was presented at 650°C. Formaldehyde selectivity was 50% mol in the 600-650°C range and maximum yield (0.31g HCHO/Kg catalyst) was found in this range; it was thus considered that 650°C for the reaction was thereby the best operating temperature.

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