Search results for "NGS"

showing 10 items of 6306 documents

Dichroism in VUV photoemission from the (0001)-surfaces of ultrathin Gd and Nd films on W(110)

1997

Abstract Ultrathin layers of Gd and Nd epitaxially grown on W(110) have been investigated using linearly and circularly polarised light at the 6.5 m NIM beamline at the BESSY storage ring in Berlin. The high quality of the films was monitored by the sharp and dispersionless surface state just below the Fermi energy. The CDAD (circular dichroism in the angular distribution of photoelectrons) measurements showed strong effects in the surface states as well as in the valence bands. The LMDAD (linear magnetic dichroism in…) from Gd(0001) showed a small, but significant splitting of the surface state. This splitting can be reproduced by numerical one-step calculations based on spin-dependent sur…

Circular dichroismValence (chemistry)Analytical chemistrychemistry.chemical_elementFermi energySurfaces and InterfacesDichroismPhotoelectric effectCondensed Matter PhysicsNeodymiumMolecular physicsSurfaces Coatings and FilmsCondensed Matter::Materials ScienceX-ray photoelectron spectroscopychemistryMaterials ChemistrySurface statesSurface Science
researchProduct

Circular dichroism in angular resolved photoemission from pure and Rb-doped C60 and C22H14 layers on platinum and tungsten

1997

Abstract Polycrystalline C60 and Pentacene films grown on W(110) and Pt(111) have been studied in valence band photoemission using circularly polarised synchrotron radiation from BESSY with special emphasis on circular dichroism in photoemission. For thin films of C60, dichroic asymmetries of about 10% occur independent of the temperature and the substrate hinting that the rotation of the topmost layer is hindered even at room temperature. For Pentacene we found asymmetries up to 50% in the region of the σ-electrons. Moreover, we found for this molecule a dichroic asymmetry in normal emission, that is a forbidden geometry. This hints on adsorption with the molecules perpendicularly oriented…

Circular dichroismValence (chemistry)Binding energyInverse photoemission spectroscopyMetals and Alloyschemistry.chemical_elementSurfaces and InterfacesElectronic structureDichroismSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsRubidiumPentacenechemistry.chemical_compoundchemistryMaterials ChemistryAtomic physicsThin Solid Films
researchProduct

Specific interaction of citrate with bis(fluorophoric) bibrachial lariat aza-crown in comparison with the other components of the Krebs cycle

2006

Clares Garcia, M. Paz, M.Paz.Clares@uv.es ; Garcia-España Monsonis, Enrique, Enrique.Garcia-Es@uv.es ; Soriano Soto, Concepcion, Concepcion.Soriano@uv.es ; Tejero Toquero, Roberto, Roberto.Tejero@uv.es

Citrate ; Krebs cycle ; Fluorescence ; NaphthaleneUNESCO::QUÍMICACrown (botany)UNESCO::QUÍMICA::Química analíticaMetals and AlloysGeneral ChemistryFluorescenceMedicinal chemistry:QUÍMICA [UNESCO]CatalysisFluorescenceSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCitric acid cyclechemistry.chemical_compoundchemistryBiochemistryMaterials ChemistryCeramics and Composites:QUÍMICA::Química analítica [UNESCO]CitrateKrebs cycleThe Krebs CycleNaphthaleneNaphthalene
researchProduct

Edilizia abusiva a Favara. Analisi dell’insediamento e sviluppo del territorio

2007

Il Piano Regolatore Generale, strumento di fondamentale importanza per lo sviluppo di un centro urbano e del suo territorio, è ancora per diverse città siciliane un obiettivo da raggiungere. I dati provenienti dall'Assessorato Regionale al Territorio e Ambiente (A.R.T.A.) indicano una Sicilia decisamente indietro nella progettazione urbanistica. Nell'isola soltanto il 40,3% dei comuni hanno un piano regolatore vigente. La mancata approvazione degli strumenti urbanistici ha influito negativamente sui processi di urbanizzazione, spesso frammentari e disorganici. Le città si sono sviluppate senza una forma, un modello riconoscibile, alimentando nei cittadini una politica che ha preferito l’edi…

City plan urban centres recovery of buildingsPiano regolatore centri urbani recupero degli edificiSettore ICAR/21 - Urbanistica
researchProduct

Drawings for engineering

2012

In the representation of knowledge can not miss all those geometric, static, functional, and specialized notions in infrastructures that characterize the shape of a Civil Engineer. We take this opportunity to show how complex the representation of a hydraulic overflow, how bold is the company wanting to bring the cross sections, the view from above, the longitudinal section. And, yet how essential is the knowledge of descriptive geometry to determine the intersections of complex surfaces, the application of engineering has great feedback. An engineer must know how to read and know how to make a drawing, must learn to identify the main characteristics, must be able to focus on the goals and …

Civil Engineering drawings homology sectionsSettore ICAR/17 - Disegno
researchProduct

Magnesium alloys laser (Nd:YAG) cladding and alloying with side injection of aluminium powder

2003

International audience; The development of the high purity magnesium alloys (such as WE43) incites the designers to reconsider them, and the car industry appears, these days, the most interested to use this kind of alloy. However, due to their ignitability and tendency to oxidation, magnesium alloys require surface treatments. A series of experiments was carried out in order to improve the corrosion resistance of two types of magnesium alloys, WE43 and ZE41. In most cases, the substrate surface was treated before laser interaction. Side injection of aluminium powder under a 3 kW cw Nd:YAG laser was employed. The deposited layers present very good bond properties. The resulting microstructur…

Cladding (metalworking)Materials scienceAlloyIntermetallic[ PHYS.COND.CM-MS ] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]General Physics and Astronomychemistry.chemical_elementMetallic surfaces02 engineering and technologyengineering.material01 natural sciencesCorrosionAluminiumCoatings0103 physical sciencesAluminium010302 applied physicsMagnesiumMetallurgySurfaces and InterfacesGeneral Chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsMicrostructureSurfaces Coatings and Filmschemistryengineering[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Aluminium powderPowders0210 nano-technologyScanning electron microscopy
researchProduct

Magnesium alloys (WE43 and ZE41) characterisation for laser applications

2004

International audience; One of the most important parameters in laser treatment is the quantity of beam energy absorbed by the substrate. Despite its important role played in laser processes, this factor is rarely available for the laser sources wavelengths and at high temperatures reached during such treatments. A series of experiments were carried out in order to characterise, from this point of view, two types of magnesium alloys, WE43 and ZE41, often used in laser applications (cladding, alloying, welding, etc.). The results represent an important step in order to understand Mg-alloys behaviour under laser beam action.

Cladding (metalworking)Materials science[ PHYS.COND.CM-MS ] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]General Physics and Astronomychemistry.chemical_element02 engineering and technologySubstrate (electronics)Weldinglaw.inventionAbsorptionCoating0203 mechanical engineeringlawLaser treatmentMicrostructureLaser beamsMagnesiumMetallurgySurfaces and InterfacesGeneral Chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsLaserSurfaces Coatings and FilmsWavelength020303 mechanical engineering & transportschemistryMagnesium alloys[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]0210 nano-technologyBeam energy
researchProduct

MoSi2 laser cladding—A new experimental procedure: double-sided injection of MoSi2 and ZrO2

2003

International audience; In the last decade, development of low density advanced material systems for service at temperatures up to 1300 °C was one of the goals of many researches. This kind of material should mainly have moderate fracture toughness and should exhibit oxidation resistant behaviour at low and intermediate temperature. One of the most studied materials continues to be the intermetallic compound MoSi2. The molybdenum disilicide has been considered as an attractive candidate due to its melting point (2030 °C) and excellent oxidation resistance at high temperatures. The main problem associated with the MoSi2 layer synthesized using laser beam is the layer fragility. To avoid this…

Cladding (metalworking)TechnologyMaterials scienceCladdingMetallurgyMolybdenum disilicideIntermetallic[ PHYS.COND.CM-MS ] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Laser beam weldingLaserSurfaces and InterfacesGeneral ChemistrypowderCondensed Matter PhysicsMicrostructureSurfaces Coatings and FilmsMoSi2chemistry.chemical_compoundFracture toughnesschemistryMaterials ChemistryMelting point[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]ZrO2Cubic zirconia
researchProduct

Some new fixed point results in non-Archimedean fuzzy metric spaces

2013

In this paper, we introduce the notions of fuzzy $(\alpha,\beta,\varphi)$-contractive mapping, fuzzy $\alpha$-$\phi$-$\psi$-contractive mapping and fuzzy $\alpha$-$\beta$-contractive mapping and establish some results of fixed point for this class of mappings in the setting of non-Archimedean fuzzy metric spaces. The results presented in this paper generalize and extend some recent results in fuzzy metric spaces. Also, some examples are given to support the usability of our results.

Class (set theory)Computer sciencebusiness.industryMathematics::General Mathematicsfuzzy α-φ-ψ-contractive mappingsApplied Mathematicsfuzzy (α β ϕ)-contractive mappingslcsh:QA299.6-433Usabilitylcsh:AnalysisFixed pointFuzzy logicFuzzy metric spacefuzzy α-β-contractive mappingsAlgebrafuzzy metric spacesSettore MAT/05 - Analisi Matematicanon-Archimedean fuzzy metric spacesFuzzy metric spaces non-Archimedean fuzzy metric spaces fuzzy $(\alpha\beta\varphi)$-contractive mappings fuzzy $\alpha$-$\phi$-$\psi$-contractive mappings fuzzy $\alpha$-$\beta$-contractive mappings.businessAnalysisNonlinear Analysis
researchProduct

Correspondence between some metabelian varieties and left nilpotent varieties

2021

Abstract In the class of left nilpotent algebras of index two it was proved that there are no varieties of fractional polynomial growth ≈ n α with 1 α 2 and 2 α 3 instead it was established the existence of a variety of fractional polynomial growth with α = 7 2 . In this paper we investigate similar problems for varieties of commutative or anticommutative metabelian algebras. We construct a correspondence between left nilpotent algebras of index two and commutative metabelian algebras or anticommutative metabelian algebras and we prove that the codimensions sequences of the corresponding algebras coincide up to a constant. This allows us to transfer the above results concerning varieties of…

Class (set theory)Pure mathematicsAlgebra and Number TheoryAnticommutativityFractional polynomialVarietiesMathematics::Rings and Algebras010102 general mathematicsGrowth01 natural sciencesSettore MAT/02 - AlgebraMathematics::Group TheoryTransfer (group theory)NilpotentCodimension0103 physical sciences010307 mathematical physics0101 mathematicsVariety (universal algebra)Constant (mathematics)Commutative propertyMathematicsJournal of Pure and Applied Algebra
researchProduct