Search results for "COATINGS"

showing 10 items of 2386 documents

Different regimes of electronic coupling and their influence on exciton recombination in vertically stacked InAs/InP quantum wires

2006

8 páginas, 8 figuras.

CouplingMaterials sciencePhotoluminescenceAcoustics and UltrasonicsCondensed matter physicsExcitonStackingPhysics::OpticsElectronCondensed Matter PhysicsCondensed Matter::Mesoscopic Systems and Quantum Hall EffectSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsWavelengthCondensed Matter::Materials ScienceStack (abstract data type)Quantum
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Symmetry and Stability of the Rutile-Based TiO2 Nanowires: Models and Comparative LCAO-Plane Wave DFT Calculations

2012

The rod symmetry groups for monoperiodic (1D) nanostructures have been applied for construction of models for bulk-like titania nanowires (NWs) cut from a rutile-based 3D crystal along the direction of a chosen crystallographic symmetry axis (in this study we consider only Ti atom-centered axes). The most stable [001]-oriented TiO2 NWs with rhombic cross sections are found to display the energetically preferable {110} facets only, while the nanowires with quasi-square sections across the [110] axis are formed by the alternating {110} and {001} facets. For simulations on rutile-based nanowires possessing four different diameters for each NW type, we have performed comparative large-scale ab …

Crystallographic point groupMaterials sciencePlane waveAb initioNanowireSymmetry groupMolecular physicsSymmetry (physics)Surfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsGeneral EnergyComputational chemistryLinear combination of atomic orbitalsDensity functional theoryPhysical and Theoretical ChemistryThe Journal of Physical Chemistry C
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Grazing-Incidence X-ray Diffraction Study of Octadecanoic Acid Monolayers

1998

We report the observation of X-ray scattering profiles from monolayers of octadecanoic acid in the vicinity of room temperature and evidence for the existence near room temperature of all four hexatic rotator phases L2d, Ov, L‘1, and LS, which differ in the details of their molecular tilt. While the incontrovertible triple-reflection signature of the chiral L‘1 phase was not observed, we propose that the previously reported rapid annealing behavior in this phase can lead to the disappearance of one, and in some cases two, of the three peaks.

CrystallographyChemistryAnnealing (metallurgy)ScatteringX-ray crystallographyMonolayerMaterials ChemistryPhysical and Theoretical ChemistrySurfaces Coatings and FilmsThe Journal of Physical Chemistry B
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Asymmetric [N–I–N]+ halonium complexes

2020

The first asymmetric halogen-bonded iodonium complexes [I(py)(4-DMAP)]PF6 (2c) and [I(py)(4-Etpy)]PF6 (2e) were prepared via [N–Ag–N]+ → [N–I–N]+ cation exchange of their analogous 2-coordinate silver complexes. The complexes were characterised by 1H and 1H–15N HMBC NMR spectroscopy, and single crystal X-ray crystallography.

CrystallographyChemistryMaterials ChemistryMetals and AlloysCeramics and CompositesHalonium ionGeneral ChemistryNuclear magnetic resonance spectroscopySingle crystalCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsChemical Communications
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Acyclic imidoselenium(ii) dihalides: synthesis and X-ray structures of ClSe[N(But)Se]nCl (n = 1, 2)

2000

The reaction of SeCl2 with tert-butylamine in THF yields the acyclic imidoselenium(II) dichlorides ClSeN(But)NSeCl and ClSeN(But)SeN(But)SeCl, in addition to the six-membered ring Se3(NBut)3.

CrystallographyChemistryStereochemistryMaterials ChemistryMetals and AlloysCeramics and CompositesX-rayGeneral ChemistryRing (chemistry)CatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsChemical Communications
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Morphologische Strukturen und Rißbildung in kristallinen, makromolekularen Stoffen

1962

Nach einem kurzen Uberblick uber die heutigen Kenntnisse der morphologischen Strukturen (Lamellen, Fibrillen und Spharolithe) werden die Versuche besprochen, und mit Hilfe von Permeations- und Diffusionsmessungen an Terylenfilmen in Abhangigkeit vom Kristallisationsgrade und der Temperatur einen Einblick in das innere Rissystem won makromolekularen Werkstoffen zu bekommen. Es zeigt sich, das man bei schonender thermischer und mechanischer Behandlung eine grobere durchgehende Risbildung u. entsprechende Korrosionsanfalligkeit durchaus vermeiden werden kann. Kristallisiert man zu lange bei zu hohen Temperaturen so tritt Risbildung auf. Hier kommen dann mikroskopische Untersuchungen sowie solc…

CrystallographyCrystal densityMechanics of MaterialsChemistryMechanical EngineeringMaterials ChemistryMetals and AlloysEnvironmental ChemistryGeneral MedicineSurfaces Coatings and FilmsMaterials and Corrosion/Werkstoffe und Korrosion
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Dynamic segregation during ferrite oxidation revealed by XPS

2002

Dynamic segregation phenomena were revealed by XPS during the oxidation of some ferrites (Fe 2.5 Ti 0.5 O 4 , Fe 2.5 Ni 0.5 O 4 , Fe 2 CrO 4 and FeCr 2 O 4 ). This kind of phenomenon induces, at a low temperature (below room temperature), drastic changes in the cationic composition of the most external layers. Dynamic segregation is a function of the cationic composition, the oxidation capability and the morphology of these ferrites. Although dynamic segregation seems to be a quite frequent phenomenon that often can be observed during ferrite oxidation, there are materials in existence where it does not appear, such as molybdenum ferrite.

CrystallographyMaterials sciencechemistryX-ray photoelectron spectroscopyMolybdenumMaterials ChemistryCationic polymerizationFerrite (magnet)chemistry.chemical_elementSurfaces and InterfacesGeneral ChemistryCondensed Matter PhysicsSurfaces Coatings and FilmsSurface and Interface Analysis
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Magnetic alignment of aliphatic lamellae

1993

Abstract Magnetic alignment of mesophases is normally only considered possible when the molecule contains an aromatic ring system. In this paper we report on the mesomorphous behaviour of a polyalkylacrylate resin with average sidechain length 22 and the alignment of its lamellae in cast films by annealing in a strong magnetic field.

CrystallographyNuclear magnetic resonanceAnnealing (metallurgy)ChemistryMaterials ChemistryMetals and AlloysMoleculeSurfaces and InterfacesCast filmsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsMagnetic fieldThin Solid Films
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Pressure-Induced Spin State Conversion in Antiferromagnetically Coupled Fe(II) Dinuclear Complexes

2001

The effect of pressure on the thermal dependence of the magnetic susceptibility has been investigated in the 2,2‘-bipyrimidine (bpm)-bridged iron(II) complexes of formula {[Fe(L)(NCX)2]2bpm} (X = S...

CrystallographyNuclear magnetic resonanceMaterials scienceSpin statesThermalMaterials ChemistryPhysical and Theoretical ChemistryMagnetic susceptibilitySurfaces Coatings and FilmsThe Journal of Physical Chemistry B
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Epoxidation of stilbene using supported gold nanoparticles: cumyl peroxyl radical activation at the gold nanoparticle surface.

2014

The catalytic epoxidation of cis-stilbene using cumene as a solvent in the presence of supported gold nanoparticles (AuNP) yields a mixture of cis and trans-stilbene oxides. EPR and product distribution studies support a new mechanistic proposal where oxygen centred radicals activate the AuNP surface and form active surface oxygen species responsible for the epoxidation products.

CumeneChemistryRadicalMetals and AlloysNanoparticleGeneral ChemistryPhotochemistryCatalysisProduct distribution3. Good healthSurfaces Coatings and FilmsElectronic Optical and Magnetic Materialslaw.inventionCatalysisSolventchemistry.chemical_compoundlawColloidal goldMaterials ChemistryCeramics and CompositesElectron paramagnetic resonanceChemical communications (Cambridge, England)
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