Search results for "catalytic systems"

showing 5 items of 5 documents

Polietylen liniowy małej gęstości

2002

Artykuł o charakterze przeglądowym dotyczy jednego z gatunków polietylenu, tj. liniowego polietylenu małej gęstości (PE-LLD) stanowiącego kopolimer etylenu z niewielką ilością (kilku %) wyższej l-olefiny otrzymywany metodą polimeryzacji koordynacyjnej z udziałem metaloorganicznych układów katalitycznych. Omówiono wpływ typu katalizatora, w szczególności nowoczesnych układów metalocenowych, na aktywność w kopolimeryzacji i efektywność wbudowania komonomeru do łańcucha polietylenowego. Przedstawiono przemysłowe metody otrzymywania PE-LLD oraz charakterystykę tego produktu na tle znanych gatunków polietylenu - PE-LD i PE-HD. Omówiono także wpływ budowy chemicznej PE-LLD na jego podstawowe właś…

budowa kopolimeruwłaściwościzastosowaniecopolymer structureukłady katalitycznepropertieslinear low-density polyethylenecatalytic systemsethylene/1-olefin copolymerizationliniowy polietylen małej gęstościkopolimeryzacja etylenu z l-olefinamiapplicationPolimery
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On the mechanistic behavior of highly efficient palladium-tetraphosphine catalytic systems for cross-coupling reactions: first spectroscopic and elec…

2008

Electrochemical studies carried out in conjunction with 31P NMR spectroscopy on the palladium(II)/palladium(0) halogeno complexes of the tetraphosphine 1,1′,2,2′-tetrakis(diphenylphosphino)-4,4′-di...

crystal structureDenticityredox reactionoxidative additiontetraphosphinechemistry.chemical_elementmechanism010402 general chemistryElectrochemistryPhotochemistry01 natural sciencesCoupling reactionCatalysisInorganic Chemistry[ CHIM.CATA ] Chemical Sciences/Catalysiscross-coupling reactionsferrocenylpolyphosphine complexesPhysical and Theoretical ChemistryComputingMilieux_MISCELLANEOUSelectrochemical studies010405 organic chemistryChemistryOrganic Chemistry[CHIM.CATA]Chemical Sciences/CatalysispalladiumCombinatorial chemistryOxidative addition0104 chemical sciences3. Good healthcatalytic systemsreaction kinetics31p nmr spectroscopyPalladium
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Preparation of tungstophosphoric acid/cerium-doped NH2-UiO-66 Z-scheme photocatalyst: a new candidate for green photo-oxidation of dibenzothiophene a…

2021

International audience; The goal of this study was to introduce an effective visible-light induced photocatalytic system with a good ability for photocatalytic oxidative desulfurization (PODS) and denitrogenation (PODN) using molecular oxygen (O2) as an oxidant. In this regard, tungestophosphoric acid (PW12) was supported onto cerium-doped NH2-UiO-66 (PW12/Ce-NUiO-66) and employed for the photo-oxidation of dibenzothiophene (DBT) and quinoline (Qu). Herein, using cerium (Ce) as a “mediator” facilitated the separation of charge carriers, while NH2-UiO-66 remarkably enhanced the surface area with plentiful adsorption sites and shifted the adsorption edge of PW12to the visible region. The sum …

pore volumeAdsorption edgesLight02 engineering and technology01 natural scienceschemistry.chemical_compound[SPI]Engineering Sciences [physics]quinolineVisible-light irradiationMaterials Chemistryoxidizing agentOxidative desulfurizationirradiationQuinolineCerium021001 nanoscience & nanotechnologyOxidantsFlue-gas desulfurizationCeriumDibenzothiophenePhotocatalysisCharge carrierCarrier mobility0210 nano-technologychemistry.chemical_element010402 general chemistryMaximum EfficiencyCatalysisArticleuraniumAdsorptionphosphotungstic acidpore size distributiondibenzothiophene derivativegreen chemistryphotooxidationDopingdesulfurizationGeneral Chemistrysurface areaPhotocatalytic systems0104 chemical sciencesVisible light inducedDibenzothiophenesTungstophosphoric acidMolecular oxygenPhotocatalytic activitychemistryadsorptiondesorptionoxygenphotocatalysisNuclear chemistrycatalyst
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Optical properties of TiO2 suspensions: Influence of pH and powder concentration on mean particle size

2007

WOS: 000250584100025

Work (thermodynamics)Settore ING-IND/24 - Principi Di Ingegneria ChimicaEffective sizeMaterials scienceTITANIUM-DIOXIDEScatteringPARTICULATE SUSPENSIONSGeneral Chemical EngineeringAnalytical chemistryPHOTON-ABSORPTIONAQUEOUS DISPERSIONSGeneral ChemistryPERFORMANCEHETEROGENEOUS PHOTOCATALYTIC SYSTEMSIndustrial and Manufacturing EngineeringSLURRY REACTORSRADIATION ABSORPTIONAgglomerateQUANTUM YIELDSPhotocatalysisParticleParticle sizePhysics::Chemical PhysicsAbsorption (chemistry)OPERATIONAL VARIABLES
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Natural eutectogels: sustainable catalytic systems for C–C bond formation reactions

2021

Natural eutecto gels were prepared combining properties of amino acids with the ones of deep eutectic solvents. Soft materials obtained were fully characterised determining the gel-sol transition temperatures and analysing mechanical and morphological features through rheological measurements and polarised optical microscopy. All eutecto gels were tested as catalytic reaction media for the enantioselective aldol reaction and, the best performing one was also used to carry out the Michael addition. In both cases, eutecto gels proved to have a great potential as sustainable reaction media, allowing to perform processes under mild conditions, obtaining excellent yields and, in some cases, also…

Natural eutecto gelsMaterials scienceEnantioselective synthesisC-C bond formation reactionsSettore CHIM/06 - Chimica OrganicaSustainable catalytic systemssupramolecular gels ionic liquids organocatalysiPollutionCatalysisSolventQuímica OrgánicaAldol reactionRheologyMichael reactionEnvironmental ChemistryOrganic chemistryaldol reactionEnantiomeric excessEutectic system
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