Search results for "Total pressure"

showing 4 items of 14 documents

Simultaneous optimization of mobile phase composition, column nature and length to analyse complex samples using serially coupled columns

2013

Abstract The combination of the selectivity of different columns serially coupled improves the separation expectancies with regard to the separation offered by each single column. In the reported approaches, either a pre-selected isocratic mobile phase composition or gradient program, giving rise to acceptable retention, is used. In previous work (JCA 1281 (2013) 94), we showed that the approach succeeds with conventional columns, assembled through zero-dead volume couplers. In this work, the simultaneous interpretive optimization of mobile phase composition and column nature and length, based on a limited number of experimental data, is demonstrated. This approach allows an impressive redu…

Van Deemter equationSulfonamidesModels StatisticalChromatographyResolution (mass spectrometry)ChemistryComputationOrganic ChemistryAnalytical chemistryGeneral MedicineBiochemistryColumn (database)Analytical ChemistryReduction (complexity)Models ChemicalTwo-dimensional chromatographyVolume (thermodynamics)Total pressureChromatography LiquidJournal of Chromatography A
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Osmotic pressure, atomic pressure and the virial equation of state of polymer solutions: Monte Carlo simulations of a bead-spring model

1994

A recently introduced coarse-grained model of polymer chains is studied analyzing various contributions to the pressure as obtained from the virial theorem as a function of chain length N, temperature T and density ϕ. The off-lattice model of the polymer chains has anharmonic springs between the beads, but of finite extensibility, and the Morse-type interaction between beads is repulsive at very short distances and attractive at intermediate distances. Solvent molecules are not explicitly included. It is found that the covalent forces along the chain (modelled by the spring potentials) contribute a negative term to the pressure, irrespective of temperature, which vanishes linearly in ϕ as ϕ…

chemistry.chemical_classificationPolymers and PlasticsChemistryOrganic ChemistryMonte Carlo methodAnharmonicityThermodynamicsPolymerCondensed Matter PhysicsVirial theoremInorganic ChemistrySpring (device)Materials ChemistryOsmotic pressureTotal pressureScalingMacromolecular Theory and Simulations
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Semidilute and Concentrated Polymer Solutions near Attractive Walls:  Dynamic Monte Carlo Simulation of Density and Pressure Profiles of a Coarse-Gra…

1997

Using a bead−spring model of flexible polymer chains, we study polymer adsorption from solutions onto attractive planar walls, varying both the strength of the adsorption potential e and the concentration of the solution over a wide range. Treating the case of good solvents, the profiles of density and pressure are computed and it is shown that thermal equilibrium between the adsorbed layer and the bulk solution is obtained. The case of a wall with purely repulsive potential under otherwise identical conditions is treated for comparison. It is shown that for the strongly adsorbing wall there is a pronounced layering, while a layered structure at the repulsive wall occurs only for high conce…

chemistry.chemical_classificationThermal equilibriumPolymers and PlasticsChemistryOrganic ChemistryMonte Carlo methodPolymerPolymer adsorptionSurface energyCondensed Matter::Soft Condensed MatterInorganic ChemistryAdsorptionChemical physicsMaterials ChemistryStatistical physicsTotal pressureLayeringMacromolecules
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The XMM Cluster Outskirts Project (X-COP): Thermodynamic properties of the Intracluster Medium out to $R_{200}$ in Abell 2319

2018

We present the joint analysis of the X-ray and SZ signals in A2319, the galaxy cluster with the highest signal-to-noise ratio in Planck maps and that has been surveyed within our XMM Cluster Outskirts Project (X-COP). We recover the thermodynamical profiles by the geometrical deprojection of the X-ray surface brightness, of the SZ comptonization parameter, and an accurate and robust spectroscopic measurements of the temperature. We resolve the clumpiness of the density to be below 20 per cent demonstrating that most of this clumpiness originates from the ongoing merger and can be associated to large-scale inhomogeneities. This analysis is done in azimuthally averaged radial bins and in eigh…

galaxies: clusters: general ; galaxies: clusters: intracluster medium – X-rays; galaxies: clusters – intergalactic mediumgalaxies: clusters: intracluster medium – X-raysCosmology and Nongalactic Astrophysics (astro-ph.CO)galaxies: clusters: intracluster medium[ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph]FOS: Physical sciencesAstrophysicsAstrophysics::Cosmology and Extragalactic Astrophysics01 natural scienceslaw.inventionlawIntracluster medium0103 physical sciencesROSATCluster (physics)Surface brightnessTotal pressure010303 astronomy & astrophysicsGalaxy clusterComputingMilieux_MISCELLANEOUSAstrophysics::Galaxy AstrophysicsPhysicsgalaxies: clusters – intergalactic medium[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph]010308 nuclear & particles physicsSettore FIS/05Astronomy and AstrophysicsAstronomy and AstrophysicX-rays: galaxies: clusterGalaxySpace and Planetary Sciencegalaxies: clusters: generalX-rays: galaxies: clustersintergalactic mediumHydrostatic equilibrium[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]Astrophysics - Cosmology and Nongalactic Astrophysics
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