Search results for "Ceramic"

showing 10 items of 2129 documents

The Electronic Structure of Hexagonal BaCoO3

1999

Abstract TB–LMTO–ASA band structure calculations within the local spin density approximation have been performed to explain the magnetic and transport properties of BaCoO3. The calculations predict a magnetic and metallic ground state as energetically favored. BaCoO3 shows no long-range magnetic ordering, however, and only poor conductivity. The magnetic energy is low and the compound shows glassy susceptibility behavior at low temperatures. From the band structure we find Mott–Hubbard localization to be unlikely, and instead propose Anderson localization as a possible origin of the observed behavior. Calculations on slightly distorted structures exclude the possibility of a Peierls distort…

Anderson localizationMagnetic energyCondensed matter physicsChemistryElectronic structureCondensed Matter PhysicsElectron localization functionElectronic Optical and Magnetic MaterialsInorganic ChemistryTight bindingMaterials ChemistryCeramics and CompositesCondensed Matter::Strongly Correlated ElectronsPhysical and Theoretical ChemistryElectronic band structureGround stateAnderson impurity modelJournal of Solid State Chemistry
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From attraction to repulsion : anion–π interactions between bromide and fluorinated phenyl groups

2011

Anion–π interactions in crystals of fluorobenzyl ammonium salts depend on the degree of fluorination at the aromatics.

AnionsBromidesBenzylaminesHalogenationInorganic chemistryMolecular ConformationChemieElectronsCrystallography X-RayCatalysisPiperazinesDegree (temperature)Ionchemistry.chemical_compoundBromidePolymer chemistryMaterials ChemistryAmmoniumMetals and AlloysHydrogen BondingGeneral ChemistryAttractionSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsFluorobenzenesQuaternary Ammonium CompoundschemistryCeramics and Composites
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Cooperativity of H-bonding and anion–π interaction in the binding of anions with neutral π-acceptors

2012

A rare anion-π complex between bromide and a neutral receptor is reported and related receptor systems are studied with a series of anions. The interaction is observed in the solid state and in solution, and further evidence for it is obtained by a computational study.

AnionsBromidesModels MolecularMagnetic Resonance SpectroscopyChemistryHydrogen bondInorganic chemistryChemieMolecular ConformationMetals and AlloysSolid-stateHydrogen BondingCooperativityGeneral ChemistryCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsIonCrystallographychemistry.chemical_compoundBromideBenzamidesMaterials ChemistryCeramics and Compositesta116Chemical Communications
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A highly enantioselective abiotic receptor for malate dianion in aqueous solution

2006

The highly enantioselective molecular recognition of the malate dianion by a synthetic receptor in aqueous solution has been studied by potentiometric titrations, mass spectrometry (ESI-MS), diffusion measurements (PGSE NMR) and molecular modeling. Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es

AnionsModels MolecularMalate dianionSpectrometry Mass Electrospray IonizationMagnetic Resonance SpectroscopyMolecular modelUNESCO::QUÍMICADiffusionPotentiometric titrationMalatesMolecular modelingAbiotic receptorMass spectrometry:QUÍMICA [UNESCO]CatalysisSubstrate SpecificityMolecular recognitionComputational chemistryMaterials ChemistryOrganic chemistryAqueous solutionReceptorAbiotic componentEnantioselectiveAqueous solutionMolecular StructureChemistrySpectrometryMeasurementsMetals and AlloysEnantioselective synthesisWaterHydrogen BondingStereoisomerismGeneral ChemistryGeneral MedicineUNESCO::QUÍMICA::Química macromolecularCombinatorial chemistrySurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsSolutionsCeramics and CompositesPotentiometryEnantioselective ; Abiotic receptor ; Malate dianion ; Aqueous solution ; Spectrometry ; Measurements ; Molecular modeling:QUÍMICA::Química macromolecular [UNESCO]
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Sterically geared tris-thioureas; transmembrane chloride transporters with unusual activity and accessibility

2015

Tris-N-arylthioureas derived in one step from 1,3,5-tris(aminomethyl)-2,4,6-triethylbenzene are remarkably effective anion carriers. With optimised aryl substituents their activities come close to the best currently known, suggesting that they might find use as readily available standards in anion transport research.

AnionsModels MolecularTrisSteric effectsCrystallography X-RayChlorideCatalysisPhysico-chimie généralechemistry.chemical_compoundChloridesMaterials ChemistrymedicineChimieMoleculeOrganic chemistryta116Ion transporterIon TransportMolecular StructureChemistryArylThioureatransmembrane anion carriersMetals and Alloystransmembrane transportersGeneral ChemistryCombinatorial chemistryTransmembrane proteinSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsChimie organiqueThioureaCeramics and Compositesmedicine.drugChemical Communications
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Thermo-responsive hydrogels from cellulose-based polyelectrolytes and catanionic vesicles for biomedical application.

2016

In this study, negatively charged catanionic vesicles/hydrophobically modified hydroxyethylcellulose polymers thermo-responsive hydrogels have been fabricated. Vesicular aggregates were found to act as multifunctional junctions for networking of modified-cellulose water solutions. The contributions of the electrostatic and hydrophobic interactions were evaluated by changing either vesicles composition or the polymer hydrophobic substitution. Thermal-induced size and lamellarity of hydrogel-enclosed vesicles were detected, with further polygonal shape changes induced by cellulose-based polymer addition. The thermal transition was also found to tune hydrogel mechanical behaviour. The network …

AnionsProton Magnetic Resonance SpectroscopyBiomedical EngineeringBiomedical TechnologyCeramics and CompositeBiomaterialsDiffusioncatanionic vesicleTheophyllineCationsCellulosecatanionic vesicles; cellulose; diffusion; hydrogel; NMR; rheology; Ceramics and Composites; Biomaterials; Biomedical Engineering; 2506ViscositydiffusionTemperatureHydrogelsBiomaterialPolyelectrolytescelluloseNMRElasticityDrug LiberationSettore CHIM/09 - Farmaceutico Tecnologico Applicativocatanionic vesiclesCeramics and Compositesrheologyhydrogel2506RheologyJournal of biomedical materials research. Part A
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Experimental investigation of anion-π interactions : Applications and biochemical relevance

2015

Chemical communications 52(9), 1778 - 1795(2016). doi:10.1039/C5CC09072E

Anionsanion-pi interactionsSolid-stateChemieNanotechnology010402 general chemistry01 natural sciencesCatalysisIonGas phasekemialliset sidoksetTime frameMaterials Chemistrysupramolekulaarinen kemiaanioni-π-vuorovaikutus010405 organic chemistryChemistryIntermolecular forceMetals and AlloysGeneral Chemistry5400104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialsintermolecular forcesnon-covalent interactionsChemical physicsddc:540Ceramics and Composites
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Microporous alumina membranes electrochemically grown

2003

Abstract The electrochemical fabrication of alumina membranes by anodizing of aluminium in phosphoric acid and oxalic acid solutions, in the temperature interval from −1 to 16 °C, was investigated in order to study the influence of different parameters (initial treatment of aluminium surface, nature and composition of electrolyte, temperature) on the final characteristics of the membranes. Porous layers were grown using a linear potential scan at 0.2 V s −1 up to 160 V in H 3 PO 4 solution and 70 V in oxalic acid solution. The efficiency of porous layer formation was calculated by using Faraday's law and weight measurements. Pore size distribution and porosity of membranes prepared in 0.4 M…

AnodizingGeneral Chemical EngineeringOxalic acidInorganic chemistrychemistry.chemical_elementElectrolyteOxalatechemistry.chemical_compoundAluminium anodizing Anodic porous oxide Ceramic membrane Membrane preparation Porous aluminaCeramic membraneMembranechemistryAluminiumElectrochemistryPhosphoric acidElectrochimica Acta
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Spectroelectrochemistry of cytochrome c and azurin immobilized in nanoporous antimony-doped tin oxide

2011

Stable immobilization of two redox proteins, cytochrome c and azurin, in a thin film of highly mesoporous antimony-doped tin oxide is demonstrated via UV-vis spectroscopic and electrochemical investigation.

AntimonyMaterials scienceInorganic chemistrychemistry.chemical_elementElectrochemistryRedoxCatalysisNanoporesAntimonyAzurinMaterials ChemistrybiologyNanoporousCytochrome ctechnology industry and agricultureMetals and AlloysCytochromes cTin CompoundsElectrochemical TechniquesGeneral Chemistryequipment and suppliesTin oxideSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsImmobilized ProteinschemistryCeramics and Compositesbiology.proteinSpectrophotometry UltravioletAdsorptionAzurinMesoporous materialChemical Communications
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First total synthesis of antiostatin A1, a potent carbazole-based naturally occurring antioxidant.

2009

The first total synthesis of the potent antioxidant antiostatin A1 is reported, where its key features rely on a chemo- and regioselective rhodium-catalysed crossed alkyne cyclotrimerisation reaction applying functionalised ynamides and a palladium-catalysed arylamidation reaction.

Antioxidantmedicine.medical_treatmentCarbazolesAlkyneAntioxidantsCatalysischemistry.chemical_compoundAntiostatin A1Materials ChemistrymedicineOrganic chemistryRhodiumchemistry.chemical_classificationMolecular StructureCarbazoleMetals and AlloysTotal synthesisRegioselectivityStereoisomerismGeneral ChemistryKey featuresSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialschemistryCyclizationCeramics and CompositesPalladiumChemical communications (Cambridge, England)
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