Search results for "High activity"

showing 3 items of 13 documents

The selective oxidative dehydrogenation of ethane over hydrothermally synthesised MoVTeNb catalysts

2002

Mo–V–Te–Nb metal oxide catalysts prepared by hydrothermal synthesis and heat-treated in N2 at high temperatures (600–700 °C) show high activity and selectivity for the oxidative dehydrogenation of ethane to ethene. Yields of ethene of 75% have been obtained at 400 °C on the best catalysts. Dejoz Garcia, Ana Maria, Ana.M.Dejoz@uv.es

UNESCO::QUÍMICAOxideOxidative phosphorylation:QUÍMICA [UNESCO]CatalysisCatalysisMetalchemistry.chemical_compoundMaterials ChemistryHydrothermal synthesisOrganic chemistryHigh activityHydrothermal synthesisDehydrogenationEthaneCatalystsUNESCO::QUÍMICA::Química inorgánicaChemistryMetals and AlloysGeneral Chemistry:QUÍMICA::Química inorgánica [UNESCO]Surfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsOxidative dehydrogenation ; Hydrothermal synthesis ; Ethane ; Catalystsvisual_artCeramics and Compositesvisual_art.visual_art_mediumSelectivityOxidative dehydrogenationChem. Commun.
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Titanium and zirconium complexes containing the new 2,3-dimethyl-1,4-diphenylcyclopentadienyl ligand. Synthesis, characterization and polymerization …

2004

Abstract An easy and inexpensive three-step synthesis of new 2,3-dimethyl-1,4-diphenylcyclopentadiene (3) ligand and the titanium and zirconium homometallocene dichlorides [TiCl2(η5-C5H-2,3-Me2-1,4-Ph2)2] (4), [ZrCl2(η5-C5H-2,3-Me2-1,4-Ph2)2] (5), and the mixed ligand zirconium complex [ZrCl2(η5-C5H-2,3-Me2-1,4-Ph2)(η5-C5H5)] (6) prepared thereof are described. The polymerization of ethene using 4–6/MAO catalysts revealed that zirconocene complexes 5 and 6 displayed moderate and high activity, respectively, whereas the titanium catalyst 4/MAO was inactive. The crystal structures of 4 and 5 were determined by X-ray crystallography.

ZirconiumChemistryLigandOrganic Chemistrychemistry.chemical_elementCrystal structureMixed ligandBiochemistryCatalysisInorganic ChemistryPolymerizationPolymer chemistryMaterials ChemistryHigh activityOrganic chemistryPhysical and Theoretical ChemistryTitaniumJournal of Organometallic Chemistry
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Engineering faster transglycosidases and their acceptor specificity

2019

Transglycosidases are enzymes that have the potential to catalyze the synthesis of a wide range of high-value compounds starting from biomass-derived feedstocks. Improving their activity and broadening the substrate range are important goals to enable the widespread application of this family of biocatalysts. In this work, we engineered 20 mutants of the rice transglycosidase Os9BGlu31 and evaluated their catalysis in 462 reactions over 18 different substrates. This allowed us to identify mutants that expanded their substrate range and showed high activity, including W243L and W243N. We also developed double mutants that show very high activity on certain substrates and exceptional specific…

chemistry.chemical_classification010405 organic chemistryExternal validationSubstrate (chemistry)010402 general chemistry01 natural sciencesPollutionAcceptorCombinatorial chemistry0104 chemical sciencesCatalysisEnzymechemistryCheminformaticsEnvironmental ChemistryHigh activityGreen Chemistry
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