Search results for "NGS"

showing 10 items of 6306 documents

Algebraic and logical characterizations of deterministic linear time classes

1997

In this paper an algebraic characterization of the class DLIN of functions that can be computed in linear time by a deterministic RAM using only numbers of linear size is given. This class was introduced by Grandjean, who showed that it is robust and contains most computational problems that are usually considered to be solvable in deterministic linear time.

AlgebraClass (set theory)Turing machinesymbols.namesakeGlobal functionsymbolsComputational problemBinary stringsAlgebraic numberCharacterization (mathematics)Time complexityMathematics
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On Meet-Complements in Cohn Geometries

1993

Within the frame of projective lattice geometry, the present paper investigates classes of meet-complements in Cohn geometries and especially in Ore and Bezout geometries. The algebraic background of these geometries is given by torsion free modules over domains — in particular Ore and Bezout domains. 1

AlgebraMathematics (miscellaneous)Applied MathematicsMathematics::Rings and AlgebrasTorsion (algebra)Computer Science::Symbolic ComputationAlgebraic numberMathematicsResults in Mathematics
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A Lattice-Geometric Proof of Wedderburn’s Theorem

1993

This note presents a proof of Wedderburn’s theorem concerning the classification of semisimple rings within the conceptual frame of projective lattice geometry.

AlgebraPure mathematicsLattice (module)Mathematics (miscellaneous)Wedderburn's little theoremApplied MathematicsMathematics::Rings and AlgebrasConceptual frameGeometric proofMathematicsAnalytic proofResults in Mathematics
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The defined adsorption site of sodium on the TiO2(110)–(1×1) surface

2004

The adsorption site of sodium on the TiO2(1 1 0)–(1 × 1) surface was studied by extended X-ray absorption fine structure. For coverage ranging between 0.25 and 0.5 ML, we find that sodium is on an ‘in-between' site where it is bound to two bridging oxygen atoms at 2.25 Å and one in-plane oxygen atom at 2.40 Å, in full agreement with DFT calculations. At higher coverage the site becomes an hollow site where the sodium atom is equidistant to the three oxygen atoms at 2.30 Å, while metallic sodium clusters are also formed at the surface.

Alkali metalsSodiumInorganic chemistrychemistry.chemical_element02 engineering and technologyExtended X-ray absorption fine structure (EXAFS)01 natural sciencesOxygenMetalAdsorption0103 physical sciencesAtomMaterials Chemistry010306 general physicsTitanium oxideExtended X-ray absorption fine structureChemistrySurfaces and Interfaces021001 nanoscience & nanotechnologyCondensed Matter PhysicsAlkali metalSurfaces Coatings and FilmsCrystallographyvisual_artvisual_art.visual_art_mediumAbsorption (chemistry)0210 nano-technologySurface Science
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High-Pressure Phase Diagram and Superionicity of Alkaline Earth Metal Difluorides

2018

We study the high-pressure–high-temperature phase diagram and superionicity of alkaline earth metal (AEM) difluorides (AF2, A = Ca, Sr, Ba) with first-principles simulation methods. We find that the superionic behavior of SrF2 and BaF2 at high pressures differ appreciably from that previously reported for CaF2 [Phys. Rev. Lett. 2014, 113, 235902]. Specifically, the critical superionic temperature of SrF2 and BaF2 in the low-pressure cubic fluorite phase is not reduced by effect of compression, and the corresponding high-pressure orthorhombic contunnite phases become superionic at elevated temperatures. We get valuable microscopic insights into the superionic features of AEM difluorides in b…

Alkaline earth metalMaterials scienceIonic radiusDifluorideThermodynamics02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesFluorite0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsGeneral EnergyPhase (matter)High pressureOrthorhombic crystal systemPhysical and Theoretical Chemistry0210 nano-technologyPhase diagramThe Journal of Physical Chemistry C
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Observation of chemical reactions between alkaline-earth oxides and tungsten at high pressure and high temperature

2009

Abstract The potential chemical reactions of alkaline-earth oxides (AeO with Ae: Mg, Ca, Sr, and Ba) and tungsten are studied at high pressure and high temperature. At pressures ranging from 5 to 10 GPa and temperatures of 2000 K, a noticeable reaction between AeO and powder tungsten (W) was detected. As a product of the reaction, scheelite-structured orthotungstates (AeWO 4 ) were formed. The reactivity of alkaline-earth oxides with tungsten increases in the order Ca 2 →AeWO 4 .

Alkaline earth oxidesChemistryHigh pressureInorganic chemistrychemistry.chemical_elementGeneral Materials ScienceReactivity (chemistry)General ChemistryTungstenCondensed Matter PhysicsChemical reactionNuclear chemistryJournal of Physics and Chemistry of Solids
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2001

A new manganese(III) oxamato dimer possesing an unprecedented Mn2(μ-O2CR)(μ-OH2⋯O2 CR) core has been synthesised, structurally and magnetically characterised, and used as a catalyst for the oxidation of alkanes to alcohols and ketones by ButO2H and O2 in CH2Cl2 at rt.

Alkanechemistry.chemical_classificationChemistryDimerMetals and Alloyschemistry.chemical_elementGeneral ChemistryCrystal structureManganeseCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCatalysischemistry.chemical_compoundPolymer chemistryMaterials ChemistryCeramics and CompositesOrganic chemistryCarboxylateChemical Communications
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Sensitivity optimization with cladding-etched long period fiber gratings at the dispersion turning point

2016

This work presents a refractive index sensor based on a long period fiber grating (LPFG) made in a reduced cladding fiber whose low order cladding modes have the turning point at large wavelengths. The combination of these parameters results in an improved sensitivity of 8734 nm/refractive index unit (RIU) for the LP0,3 mode in the 1400-1650 wavelength range. This value is similar to that obtained with thin-film coated LPFGs, which permits to avoid the coating deposition step. The numerical simulations are in agreement with the experimental results. This work was supported in part by the Spanish Ministry of Education and Science-FEDER TEC2013-43679-R. J.L. Cruz also acknowledges financial s…

All-silica fiberMaterials sciencebusiness.industry010401 analytical chemistryFiber optics sensorsLong-period fiber gratingCladding (fiber optics)01 natural sciencesGraded-index fiberAtomic and Molecular Physics and Optics0104 chemical sciencesFibers single-mode010309 opticsOpticsDouble-clad fiberNormalized frequency (fiber optics)Fiber Bragg grating0103 physical sciencesFiber Bragg gratingsDispersion-shifted fiberbusinessOptics Express
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Allo-repetition in Academic Settings. Cooperation, Understanding Co-construction and Knowledge Negotiation in the Medical Section of the ELFA Corpus

2015

In recent years, spoken academic ELF (English as a Lingua Franca) has been an object of in- creasing interest in linguistic and communication studies thanks to the position of academia as “one of the domains which have most eagerly adopted English as their common language in in- ternational communication” (Mauranen 2006a: 146) 1. In a context where different linguistic and cultural backgrounds come together, clarity and explicitness play a prominent role. In this respect, ELF research has paid much attention to the importance of communicative strategies, the most prominent of which is repetition. ELF studies on repetition have been carried out in several do- mains, including academia. Withi…

Allo-repetitionAllo-repetition; academic communication; intercultural settings; medical discourse; knowledge negotiation; understanding co-constructionknowledge negotiationintercultural settingmedical discourseacademic communicationunderstanding co-constructionSettore L-LIN/12 - Lingua E Traduzione - Lingua Inglese
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Recent advances in the synthesis of functionalised monofluorinated compounds.

2018

Over the past few years, we have tackled the synthesis of interesting monofluorinated organic molecules, such as: dihydronaphthalene derivatives, β-fluoro sulfones and related carbonyl compounds, fluorohydrins and allylic alcohols. Overall, a wide range of modern synthetic techniques are covered in this feature article including transition-metal, photo- and organocatalysis, nucleophilic and electrophilic fluorinations, chiral auxiliaries and enantioselective catalysis.

Allylic rearrangement010405 organic chemistryChemistryMetals and AlloysEnantioselective synthesisGeneral Chemistry010402 general chemistry01 natural sciencesCombinatorial chemistryCatalysis0104 chemical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsOrganic moleculesCatalysisNucleophileOrganocatalysisElectrophileMaterials ChemistryCeramics and CompositesChemical communications (Cambridge, England)
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