Search results for "Names"

showing 10 items of 6843 documents

Testing a theoretically-based overland flow resistance law by Emmett’s database

2021

Abstract The main aim of this paper was to test a recently theoretically deduced flow resistance equation, based on a power-velocity profile, using a wide database of available measurements carried out in laboratory and field experimental runs with overland flow under simulated rainfall. In comparison with previous calibrations and validations of this theoretically deduced flow resistance equation, the used database by Emmett is characterized by a wide range of rainfall intensities (from 79.2 to 303.5 mm h−1 for laboratory runs and from 178.3 to 215.9 mm h−1 for field investigations) and bed slopes (from 0.33 to 17% for laboratory runs and from 2.9 to 33.2% for field investigations). For th…

Dimensional analysiVegetationDatabaseReynolds numberLaminar flowcomputer.software_genreSelf-similaritysymbols.namesakeWetted perimeterOverland flowVelocity profileFlow (mathematics)Flow velocityLawRainfall simulationFroude numbersymbolsSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliEnvironmental scienceSurface runoffcomputerIntensity (heat transfer)Water Science and TechnologyJournal of Hydrology
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Aggregation Behavior of Halogenated Squaraine Dyes in Buffer, Electrolytes, Organized Media, and DNA

2002

Aggregation properties of bis(3,5-dibromo-2,4,6-trihydroxyphenyl)squaraine (1) and bis(3,5-diiodo-2,4,6-trihydroxyphenyl)squaraine (2) have been examined in buffer and in the presence of electrolytes, β-cyclodextrin, micelles and DNA. These dyes were found to form aggregates in buffer and methanol−water solutions that have absorption bands blue-shifted to those of the monomeric forms. The iodo derivative 2 forms aggregates at much lower concentrations (1.7 × 10-6 M) compared to the bromo derivative 1 (2.35 × 10-6 M) in 20% (vol/vol) methanol−buffer solution. Increase in methanol concentration in methanol−water solutions resulted in the disruption of the aggregates. The intermediate dimer in…

DimerElectrolyteMicelleSurfaces Coatings and FilmsGibbs free energychemistry.chemical_compoundsymbols.namesakeMonomerchemistryPolymer chemistryMaterials ChemistrysymbolsOrganic chemistryMethanolPhysical and Theoretical ChemistryDNAEntropy (order and disorder)The Journal of Physical Chemistry B
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Anisotropic exchange coupling in the Keggin derivative K8[Co2(D2O)(W11O39)] · n D2O

1998

Abstract 20 g of the fully deuterated title compound have been prepared in polycrystalline form and investigated by inelastic neutron scattering using both thermal and cold neutrons. Magnetic dimer excitations were observed and the energy-splitting pattern resulting from the exchange coupling within the Co 2+ dimer was determined. The coupling is highly anisotropic with the parameter values J =−2.24 meV and η =0.33 based on the effective coupling Hamiltonian H =−2J[S 1z S 2z +η(S 1x S 2x +S 1y S 2y )] . The anisotropy results mainly from the single-ion anisotropy of the Co 2+ ion in the distorted octahedral coordination.

DimerGeneral Physics and AstronomyInelastic neutron scatteringIonchemistry.chemical_compoundCrystallographysymbols.namesakechemistryDeuteriumOctahedronsymbolsNeutronPhysical and Theoretical ChemistryAnisotropyHamiltonian (quantum mechanics)Chemical Physics Letters
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Determination of Individual Gibbs Energies of Anion Transfer and Excess Gibbs Energies Using an Electrochemical Method Based on Insertion Electrochem…

2011

A method is presented to determine, individually and with minimal extra-thermodynamic assumptions, the Gibbs energy for anion transfer between two solvents using solid state electrochemistry of alkynyldiphosphine dinuclear Au(I) complexes (AuC2R)2PPh2C6H4PPh2 (L1, R = Fc; L2, R = C6H4Fc) and the heterometallic Au(I)–Cu(I) [{Au3Cu2(C2R)6}Au3(PPh2C6H4PPh2)3](PF6)2 (L3, R = Fc; L4, R = C6H4Fc) cluster complexes containing ferrocenyl units. These compounds exhibit a well-defined, essentially reversible solid-state oxidation in contact with different electrolytes, based on ferrocenyl-centered oxidation processes involving anion insertion. Voltammetric data can be used for a direct measurement of…

Dimethyl sulfoxideGeneral Chemical EngineeringInorganic chemistrySolvationGeneral ChemistryElectrolyteElectrochemistryIonGibbs free energySolventchemistry.chemical_compoundsymbols.namesakechemistryCluster (physics)symbolsJournal of Chemical & Engineering Data
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Stark level crossing and optical-rf double resonance in NaK D 1 Π

1997

We report here (Lambda) -doubling splitting and permanent electric dipole moment d p measurements for a number of vibrotational levels of NaK D 1 II state. Two different methods, which are not Doppler limited, were used. Stark effect induced level crossing was registered as fluorescence polarization changes with external electric field, which allowed us to obtain, from one fit, the values of electric dipole moment and (Lambda) -doubling splitting (Delta) ef between e, f substates of an individual rotational state. Another method consisted in obtaining the ratio (Delta) ef /d p from electric field dependence of the intensity of forbidden line appeared in fluorescence as a result of e- f Star…

DipolePolarization densitysymbols.namesakeElectric dipole momentStark effectChemistryExcited stateElectric fieldTransition dipole momentsymbolsAtomic physicsMagnetic dipoleSPIE Proceedings
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A Weitzenböck formula for the damped Ornstein–Uhlenbeck operator in adapted differential geometry

2001

Abstract On the Riemannian path space we consider the Ornstein–Uhlenbeck operator associated to the Dirichlet form E (f,g)=E〈 ∇ f, ∇ g〉 H , where ∇ is the damped gradient and 〈·,·〉 H the scalar product of the Cameron–Martin space H . We prove a corresponding Weitzenbock formula restricted to adapted vector fileds: the Ricci-tensor is shown to be equal to the identity.

Dirichlet formScalar (mathematics)Mathematical analysisOrnstein–Uhlenbeck processGeneral MedicineRiemannian geometrysymbols.namesakeMathematics::ProbabilityDifferential geometrysymbolsVector fieldOrnstein–Uhlenbeck operatorRicci curvatureMathematicsComptes Rendus de l'Académie des Sciences - Series I - Mathematics
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Geometry and analysis of Dirichlet forms (II)

2014

Abstract Given a regular, strongly local Dirichlet form E , under assumption that the lower bound of the Ricci curvature of Bakry–Emery, the local doubling and local Poincare inequalities are satisfied, we obtain that: (i) the intrinsic differential and distance structures of E coincide; (ii) the Cheeger energy functional Ch d E is a quadratic norm. This shows that (ii) is necessary for the Riemannian Ricci curvature defined by Ambrosio–Gigli–Savare to be bounded from below. This together with some recent results of Ambrosio–Gigli–Savare yields that the heat flow gives a gradient flow of Boltzman–Shannon entropy under the above assumptions. We also obtain an improvement on Kuwada's duality …

Dirichlet formta111Mathematical analysisGeometryCurvatureUpper and lower boundsDirichlet distributionsymbols.namesakeBounded functionsymbolsMathematics::Metric GeometryMathematics::Differential GeometryAnalysisRicci curvatureEnergy functionalScalar curvatureMathematicsJournal of Functional Analysis
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On Boundary Value Problems for ϕ-Laplacian on the Semi-Infinite Interval

2017

The Dirichlet problem and the problem with functional boundary condition for ϕ-Laplacian on the semi-infinite interval are studied as well as solutions between the lower and upper functions.

Dirichlet problem010102 general mathematicsMathematical analysislower and upper functionsMixed boundary conditionMathematics::Spectral Theory01 natural sciencesRobin boundary conditionElliptic boundary value problemϕ-Laplacian010101 applied mathematicssymbols.namesakeModeling and SimulationDirichlet boundary conditionboundary value problemFree boundary problemsymbolsNeumann boundary conditionQA1-939Boundary value problem0101 mathematicsAnalysisMathematicsMathematicsMathematical Modelling and Analysis
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Weakened acute type condition for tetrahedral triangulations and the discrete maximum principle

2000

We prove that a discrete maximum principle holds for continuous piecewise linear finite element approximations for the Poisson equation with the Dirichlet boundary condition also under a condition of the existence of some obtuse internal angles between faces of terahedra of triangulations of a given space domain. This result represents a weakened form of the acute type condition for the three-dimensional case.

Dirichlet problemAlgebra and Number TheoryDiscretizationApplied MathematicsMathematical analysisDomain (mathematical analysis)Piecewise linear functionComputational Mathematicssymbols.namesakeMaximum principleDirichlet boundary conditionsymbolsBoundary value problemPoisson's equationMathematicsMathematics of Computation
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Branches of index-preserving solutions to systems of second order ODEs

2009

We investigate the existence of a continuum of index-preserving solutions to a Dirichlet problem associated with a parameter-dependent system of second order ordinary differential equations, developing a detailed analysis on the behaviour of the branches of nontrivial solutions. Our approach is based on the Rabinowitz global bifurcation Theorem combined with the notion of index and nullity of suitable linear boundary value problems. An application of the result to the study of branches of odd, periodic solutions for suitable systems of two linearly coupled pendulums of lenghts variables is also analyzed.

Dirichlet problemContinuum (topology)Applied MathematicsMathematical analysisOdesymbols.namesakeDirichlet boundary conditionOrdinary differential equationsymbolsOrder (group theory)Second order systems Index-preserving solutions BifurcationBoundary value problemAnalysisBifurcationMathematics
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