Search results for "diffuse reflectance spectroscopy"

showing 2 items of 2 documents

Increased conformational rigidity of humic substances by oxidative biomimetic catalysis

2005

A synthetic water-soluble meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of iron(III) chloride, Fe(TDCPPS)Cl, was employed as a biomimetic catalyst in the oxidative coupling of terrestrial humic materials. High-performance size-exclusion chromatography (HPSEC), solid-state nuclear magnetic resonance (CPMAS-(13)C NMR), electron paramagnetic resonance (EPR), and diffuse reflectance infrared spectroscopy (DRIFT) were used to follow conformational and structural changes brought about in different humic materials by the oxidative coupling. Increase in apparent weight-average molecular weight (Mw(a)) occurred invariably for all humic substances with the oxidative polymerization catalyzed …

conformationMagnetic Resonance SpectroscopySpectrophotometry InfraredPolymers and PlasticsDiffuse reflectance infrared spectroscopy (DRIFT)Biomimetic materialsaromatic compoundgel permeation chromatographyMolecular ConformationPhotochemistryIron compoundslaw.inventionPolymerizationenvironmental managementcovalent bondlawSize exclusion chromatographyBiomimetic catalysisBiomimeticsMaterials ChemistryOrganic chemistryHumic acidElectron paramagnetic resonanceInfrared spectroscopyChromatography High Pressure Liquidchemistry.chemical_classificationSettore CHIM/03 - Chimica Generale e InorganicaCarbon IsotopesChromatographyindustryCatalystsChemistrytetra(2articleelectrophoretic mobilitybiomimetic materialNuclear magnetic resonance spectroscopyunclassified drugConformationsacetic acidpriority journalCovalent bondSpectrophotometrySynthesis (chemical)High Pressure Liquidtechnology6 dichloro 3 sulfonatophenyl)porphyrinic acid derivativeInfraredOxidation-Reductionmolecular stabilityHumic materialsoxidationSettore AGR/13 - Chimica AgrariaSupramolecular chemistryBioengineeringcomplex mixturesCatalysisCatalysisdiffuse reflectance spectroscopyhumic substanceBiomaterialsalkyl etherElectron spin resonance spectroscopycomplex formationParticle SizeNuclear magnetic resonance spectroscopyHumic Substancesfree radicalbiomimetic oxidative humicelectron spin resonanceHigh performance size exclusion chromatography (HPSEC)ferrous chloridemolecular weightsolid statecarbon nuclear magnetic resonancePolymerizationSolubilitychemical structureOxidative coupling of methaneCatalysts; Conformations; Electron spin resonance spectroscopy; Infrared spectroscopy; Iron compounds; Nuclear magnetic resonance spectroscopy; Oxidation; Polymerization; Size exclusion chromatography; Solubility; Synthesis (chemical); Biomimetic catalysis; Diffuse reflectance infrared spectroscopy (DRIFT); High performance size exclusion chromatography (HPSEC); Humic materials; Biomimetic materials; acetic acid; alkyl ether; aromatic compound; biomimetic material; ferrous chloride; free radical; tetra(26 dichloro 3 sulfonatophenyl)porphyrinic acid derivative; unclassified drug; article; carbon nuclear magnetic resonance; catalysis; catalyst; chemical structure; complex formation; conformation; covalent bond; diffuse reflectance spectroscopy; electron spin resonance; electrophoretic mobility; environmental management; gel permeation chromatography; humic substance; industry; molecular stability; molecular weight; oxidation; polymerization; priority journal; solid state; technology; Biomimetics; Carbon Isotopes; Catalysis; Chromatography High Pressure Liquid; Electron Spin Resonance Spectroscopy; Humic Substances; Magnetic Resonance Spectroscopy; Molecular Conformation; Oxidation-Reduction; Particle Size; Spectrophotometry Infraredcatalyst
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Peracetylated β‐cyclodextrin as solubilizer of arylphosphines in supercritical carbon dioxide

2006

Abstract Effect of peracetylated β-cyclodextrin on the solubility of diphenyl(4-phenylphenyl)phosphine in supercritical carbon dioxide medium has been investigated. As shown by gravimetric measurements, the presence of cyclodextrin (CD) (1 equivalent) allows to increase the solubility of phosphine (P) in supercritical carbon dioxide (scCO 2 ) (40 °C, 35.2 MPa, nominal system density 0.89 g/mL). This solubility enhancement was attributed to host–guest interactions in scCO 2 as the P was recovered in the form of an inclusion complex. Furthermore, a diffuse reflectance spectroscopy study on the samples recovered after the experiments and on various CD/P solid mixtures obtained by co-grinding i…

Diffuse reflectance infrared fourier transformGeneral Chemical EngineeringInorganic chemistry010402 general chemistry01 natural scienceschemistry.chemical_compoundGravimetric measurementDifferential scanning calorimetryDifferential scanning calorimetryDiffuse reflectance spectroscopy[CHIM]Chemical SciencesPhysical and Theoretical ChemistrySolubilityComputingMilieux_MISCELLANEOUSchemistry.chemical_classificationSupercritical carbon dioxideCyclodextrin010405 organic chemistry[CHIM.MATE]Chemical Sciences/Material chemistryCondensed Matter Physics0104 chemical sciences[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistrySolubilityCarbon dioxidechemistryCarbon dioxideGravimetric analysisPhosphinePhosphine
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