Search results for "splitting"

showing 10 items of 220 documents

Effect of Reynolds number and lithium cation insertion on titanium anodization

2016

This work studies the influence of using hydrodynamic conditions (Reynolds number, Re = 0 to Re = 600) during Ti anodization and Li+ intercalation on anatase TiO2 nanotubes. The synthesized photocatalysts were characterized by using Field Emission Scanning Electron Microscope (FE-SEM), Raman Confocal Laser Microscopy, Electrochemical Impedance Spectroscopy (EIS), Mott-Schottky analysis (M-S), photoelectrochemical hydrogen production and resistance to photocorrosion tests. The obtained results showed that the conductivity of the NTs increases with Li+ intercalation and Re. The latter is due to the fact that the hydrodynamic conditions eliminate part of the initiation layer formed over the tu…

AnataseMaterials sciencehydrodynamic conditionsGeneral Chemical EngineeringIntercalation (chemistry)Analytical chemistrychemistry.chemical_element02 engineering and technology010402 general chemistry01 natural scienceswater splittingINGENIERIA QUIMICAsymbols.namesakeElectrochemistryTiO2 nanotubesPhotocurrentelectrochemical impedance spectroscopy (EIS)Titani021001 nanoscience & nanotechnology0104 chemical sciencesDielectric spectroscopyField emission microscopyElectroquímicachemistrysymbolsMott-Schottky analysisWater splitting0210 nano-technologyRaman spectroscopyTitanium
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A Heterobimetallic Anionic 3,6-Connected 2D Coordination Polymer Based on Nitranilate as Ligand

2016

In order to synthesize new coordination polymers with original architectures and interesting magnetic properties, we used the nitranilate ligand (C₆O₄(NO₂)₂2- = C₆N₂O₈2-), derived from the dianionic ligand dhbq2- (2,5-dihydroxy-1,4-benzoquinone = H₂C₆O₄2-). The use of this bis-bidentate bridging ligand led to [(DAMS)₂{FeNa(C₆N₂O₈)₃}·CH₃CN]n (1) (DAMS⁺ = C16H17N₂⁺ = 4-[4-(dimethylamino)-α-styryl]-1-methylpyridinium), a 2D heterometallic coordination polymer presenting an unprecedented structure for any anilato-based compound. This structural type is a 3,6-connected 2D coordination polymer derived from the well-known honeycomb hexagonal structure, where Fe(III) ions alternate with Na⁺ dimers …

Polymers and PlasticsCoordination polymerStereochemistryZero field splitting010402 general chemistry01 natural sciencesArticleIonlcsh:QD241-441Paramagnetismchemistry.chemical_compoundlcsh:Organic chemistrymagnetic properties high spin Fe(III) complexchemistry.chemical_classificationanilato ligands; heterometallic; coordination polymers; magnetic properties high spin Fe(III) complex010405 organic chemistryLigandCenter (category theory)Bridging ligandGeneral ChemistryPolymer0104 chemical sciencesCrystallographycoordination polymerschemistryheterometallicanilato ligandsPolymers; Volume 8; Issue 3; Pages: 89
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Synthesis and spectroscopic characterization of diethyltin (IV) derivatives of dipeptides: Crystal and molecular structure of diethyltin glycyltrosin…

1992

Dipeptide complexes of the diethyltin(IV) moiety, Et2SnL, have been synthesized, H2L being glycylglycine (H2GlyGly), glycylalanine (H2GlyAla), alanylalanine (H2AlaAla), glycylvaline (H2GlyVal), valylvaline (H2ValVal), glycylmethionine (H2GlyMet), glycyltyrosine (H2GlyTyr). The crystal and molecular structure of the complex Et2SnGlyTyr has been determined by singlecrystal X-ray diffraction. It consists of monomeric units, with the tin atom having a considerably distorted trigonal bipyramidal environment. The dipeptide acts as a tridentate ligand bonding the tin of the C2Sn fragment (equatorial carbon atoms) with the peptide nitrogen atom (equatorial) and axial (monodentate) carboxyl oxygen a…

GlycylglycineDenticityStereochemistryGeneral ChemistryNuclear magnetic resonance spectroscopyCrystal structureQuadrupole splittingInorganic ChemistryBond lengthCrystallographychemistry.chemical_compoundTrigonal bipyramidal molecular geometrychemistryMoleculeApplied Organometallic Chemistry
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Structure-Directing and High-Efficiency Photocatalytic Hydrogen Production by Ag Clusters

2014

H2 production by water splitting is hindered mainly by the lack of low-cost and efficient photocatalysts. Here we show that sub-nanometric silver clusters can catalyze the anisotropic growth of gold nanostructures by preferential adsorption at certain crystal planes of Au seeds, with the result that the final nanostructure can be tuned via the cluster/seed ratio. Such semiconducting Ag clusters are extremely stable and retain their electronic structure even after adsorption at the tips of Au nanorods, enabling various photocatalytic experiments, such as oxygen evolution from basic solutions. In the absence of electron scavengers, UV irradiation generates photoelectrons, which are stored wit…

NanostructureChemistryInorganic chemistryFermi levelOxygen evolutionGeneral ChemistryDFT calculationsBiochemistryCatalysissymbols.namesakeColloid and Surface ChemistryChemical engineeringAu nanorodsub-nanometric Ag clusterSettore CHIM/03 - Chimica Generale E InorganicaPhotocatalysissymbolsCluster (physics)Water splittingNanorodH2 productionHydrogen production
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A Douglas–Rachford method for sparse extreme learning machine

2019

Operator splittingSparse regularizationAlgorithmExtreme learning machineMathematicsMethods and Applications of Analysis
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Structural characterization of triorganotin(IV) complexes with sodium fusidate and DFT calculations

2010

Abstract Three new complexes of the steroid sodium fusidate (sodium 2-[(1 S ,2 S ,5 R ,6 S ,7 S ,10 S ,11 S ,13 S , 14 Z ,15 R ,17 R )-13-(acetyloxy)-5,17-dihydroxy-2,6,10,11-tetramethyl tetracyclo[8.7.0.0 2,7 .0 11,15 ] heptadecan-14-ylidene]-6-methylhept-5-enoate = (NaFusidate, Na FA )]), with triorganotin(IV) moieties have been prepared and investigated by conventional techniques as FTIR, Mossbauer, ESI-MS and NMR spectroscopy. The isolated compounds showed stoichiometries organotin(IV)/fusidate 1/1, R 3 Sn(IV) FA (R = Me, FA1 ; Bu, FA2 ; Ph, FA3 ). The ligand coordination sites were determined by FTIR spectroscopic measurements. In the complexes, the carboxylate group of the fusidate li…

DenticityTriorganotin(IV)Mössbauer spectroscopyLigandOrganic ChemistryInorganic chemistrychemistry.chemical_elementQuadrupole splittingNuclear magnetic resonance spectroscopyBiochemistrySteroid carboxylate Triorganotin(IV) NMRFTIRMössbauer spectroscopySteroid carboxylateNMRInorganic Chemistrychemistry.chemical_compoundCrystallographyMonomerFTIRchemistryMössbauer spectroscopyMaterials ChemistryCarboxylatePhysical and Theoretical ChemistryTin
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Quadrupole interaction of $^{8}$Li and $^{9}$Li in LiNbO$_{3}$ and the quadrupole moment of $^{9}$Li

1988

The quadrupole interaction of nuclear spin polarized8Li (I=2) and9Li (I=3/2) in LiNbO3 has been studied at room temperature. The polarization was achieved by optical pumping of a fast atomic beam with circularly polarized laser light. The atoms were implanted into a hexagonal LiNbO3 single crystal and the quadrupole splitting ofβ-NMR spectra was measured. A ratio of ¦Q(9Li)/Q(8Li)¦=0.88(4) for the nuclear quadrupole moments was deduced, yielding a new value of ¦Q(9Li)¦=25.3 (9) mb for the quadrupole moment of9Li.

Nuclear and High Energy PhysicsChemistryIsotopes of lithiumNuclear TheoryPhysics::OpticsQuadrupole splittingSpectral lineOptical pumpingQuadrupolePhysics::Accelerator PhysicsNuclear fusionNuclear Physics - ExperimentPhysics::Atomic PhysicsAtomic physicsQuadrupole mass analyzerSingle crystal
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Solution-Processed Ni-Based Nanocomposite Electrocatalysts: An Approach to Highly Efficient Electrochemical Water Splitting

2021

In this study, we report an up-scalable and low-cost solution-processed method to in situ synthesize an earth-abundant non-stoichiometric NiOx-based electrocatalytic film for water oxidation. The catalytic activity was found to be inversely proportional to the baking temperature, which varied from 50 to 500 °C. We found the formation of a hybrid nanocomposite thin film of NiOx nanocrystals (<2 nm size) inside an acetate-based organic matrix at low temperatures (<200 °C). The defective and short-range structural order of the NiOx-based nanocomposite electrocatalysts, compatible with lattice stress, low electrical conductivity, and high density of catalytically active surface species, and hig…

Service (business)NanocompositeEnergy Engineering and Power Technologywater splittingManufacturing engineeringExperimental researchSolution processedNiOx-based nanocompositeMaterials ChemistryElectrochemistryChemical Engineering (miscellaneous)Water splittingelectrocatalystsolution processingElectrical and Electronic Engineering
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Exchange Coupling Mediated by N–H···Cl Hydrogen Bonds: Experimental and Theoretical Study of the Frustrated Magnetic System in Bis(o-phenylenediamine…

2012

The title compound crystallizes in the monoclinic P2(1)/c space group with a = 11.2470(3) A, b = 5.9034(2) A, c = 12.0886(3) A, β = 115.143(1)°, and V = 726.58(4) A(3) and consists of discrete monomeric NiCl(2)(o-phenylendiamine)(2) molecules. Each o-phen ligand coordinates in a bidentate mode with the chloride ions occupying trans positions in the resulting tetragonally distorted octahedral coordination sphere. Two discrete sets of N-H···Cl hydrogen bonds link the octahedral molecules into a two-dimensional network, with type 1 interactions linking adjacent monomers along the c axis and type 2 interactions linking monomers along the diagonals in the bc plane. Analysis of the magnetic data …

DenticityCoordination sphereHydrogen bondStereochemistryZero field splittingInorganic ChemistryCrystallographychemistry.chemical_compoundOctahedronchemistryMoleculeAntiferromagnetismPhysical and Theoretical ChemistryNickel(II) chlorideInorganic Chemistry
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Ni alloy nanowires for alkaline electrolysers

In recent years, the interest towards green hydrogen has drastically increased due to the global decarbonization process. Green hydrogen is obtained by water electrolysis using only electricity from renewable sources. It is considered one of the best storage systems in terms of environmental sustainability but not in economic ones. Nowadays, the research is focused on improving the Alkaline Water Electrolysis (AE) to reduce the cost of production. An approach to improve AE performance is based on nanostructured electrodes characterized by high electrocatalytic activity due to the very high surface area. In fact, the development of more efficient electrolysers with low-cost electrode-electro…

Ni alloyalkaline electrolyserSettore ING-IND/23 - Chimica Fisica ApplicataNanostructured electrodewater splitting
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