The Experts below are selected from a list of 85536 Experts worldwide ranked by ideXlab platform
Ryosuke Yano - One of the best experts on this subject based on the ideXlab platform.
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Fast and Accurate Calculation of dilute quantum gas using Uehling-Uhlenbeck model equation
Journal of Computational Physics, 2017Co-Authors: Ryosuke YanoAbstract:The Uehling-Uhlenbeck (U-U) model equation is studied for the fast and Accurate Calculation of a dilute quantum gas. In particular, the direct simulation Monte Carlo (DSMC) method is used to solve the U-U model equation. DSMC analysis based on the U-U model equation is expected to enable the thermalization to be Accurately obtained using a small number of sample particles and the dilute quantum gas dynamics to be calculated in a practical time. Finally, the applicability of DSMC analysis based on the U-U model equation to the fast and Accurate Calculation of a dilute quantum gas is confirmed by calculating the viscosity coefficient of a Bose gas on the basis of the Green-Kubo expression and the shock layer of a dilute Bose gas around a cylinder.
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Numerical method toward fast and Accurate Calculation of dilute quantum gas using Uehling-Uhlenbeck model equation
arXiv: Computational Physics, 2015Co-Authors: Ryosuke YanoAbstract:The numerical method toward the fast and Accurate Calculation of the dilute quantum gas is studied by proposing the Uehing-Uhlenbeck (U-U) model equation. In particular, the direct simulation Monte Carlo (DSMC) method is used to solve the U-U model equation. The DSMC analysis of the U-U model equation surely enables us to obtain the Accurate thermalization using a small number of sample particles and calculate the dilute quantum gas dynamics in practical time. Finally, the availability of the DSMC analysis of the U-U model equation toward the fast and Accurate Calculation of the dilute quantum gas is confirmed by calculating the viscosity coefficient of the Bose gas on the basis of Green-Kubo expression or shock layer of the dilute Bose gas around a circular cylinder
Carlos M. Silva - One of the best experts on this subject based on the ideXlab platform.
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Universal model for Accurate Calculation of tracer diffusion coefficients in gas, liquid and supercritical systems.
Journal of chromatography. A, 2013Co-Authors: Patrícia F. Lito, Ana L. Magalhães, José R. B. Gomes, Carlos M. SilvaAbstract:In this work it is presented a new model for Accurate Calculation of binary diffusivities (D12) of solutes infinitely diluted in gas, liquid and supercritical solvents. It is based on a Lennard-Jones (LJ) model, and contains two parameters: the molecular diameter of the solvent and a diffusion activation energy. The model is universal since it is applicable to polar, weakly polar, and non-polar solutes and/or solvents, over wide ranges of temperature and density. Its validation was accomplished with the largest database ever compiled, namely 487 systems with 8293 points totally, covering polar (180 systems/2335 points) and non-polar or weakly polar (307 systems/5958 points) mixtures, for which the average errors were 2.65% and 2.97%, respectively. With regard to the physical states of the systems, the average deviations achieved were 1.56% for gaseous (73 systems/1036 points), 2.90% for supercritical (173 systems/4398 points), and 2.92% for liquid (241 systems/2859 points). Furthermore, the model exhibited excellent prediction ability. Ten expressions from the literature were adopted for comparison, but provided worse results or were not applicable to polar systems. A spreadsheet for D12 Calculation is provided online for users in Supplementary Data.
Andrey I. Frolov - One of the best experts on this subject based on the ideXlab platform.
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Accurate Calculation of Solvation Free Energies in Supercritical Fluids by Fully Atomistic Simulations: Probing the Theory of Solutions in Energy Representation
Journal of chemical theory and computation, 2015Co-Authors: Andrey I. FrolovAbstract:Accurate Calculation of solvation free energies (SFEs) is a fundamental problem of theoretical chemistry. In this work we perform a careful validation of the theory of solutions in energy representation (ER method) developed by Matubayasi et al. [J. Chem. Phys. 2000, 113, 6070–6081] for SFE Calculations in supercritical solvents. This method can be seen as a bridge between the molecular simulations and the classical (not quantum) density functional theory (DFT) formulated in energy representation. We performed extensive Calculations of SFEs of organic molecules of different chemical natures in pure supercritical CO2 (sc-CO2) and in sc-CO2 with addition of 6 mol % of ethanol, acetone, and n-hexane as cosolvents. We show that the ER method reproduces SFE data calculated by a method free of theoretical approximations (the Bennett’s acceptance ratio) with the mean absolute error of only 0.05 kcal/mol. However, the ER method requires by an order less computational resources. Also, we show that the quality of E...
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Accurate Calculation of the hydration free energies of biologically active molecules using the reference interaction site model
2011Co-Authors: David S. Palmer, Ekaterina L. Ratkova, Andrey I. Frolov, Volodymyr P. Sergiievskyi, Maxim V. FedorovAbstract:Describes the Accurate Calculation of the hydration free energies of biologically active molecules using the reference interaction site model.
Patrícia F. Lito - One of the best experts on this subject based on the ideXlab platform.
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Universal model for Accurate Calculation of tracer diffusion coefficients in gas, liquid and supercritical systems.
Journal of chromatography. A, 2013Co-Authors: Patrícia F. Lito, Ana L. Magalhães, José R. B. Gomes, Carlos M. SilvaAbstract:In this work it is presented a new model for Accurate Calculation of binary diffusivities (D12) of solutes infinitely diluted in gas, liquid and supercritical solvents. It is based on a Lennard-Jones (LJ) model, and contains two parameters: the molecular diameter of the solvent and a diffusion activation energy. The model is universal since it is applicable to polar, weakly polar, and non-polar solutes and/or solvents, over wide ranges of temperature and density. Its validation was accomplished with the largest database ever compiled, namely 487 systems with 8293 points totally, covering polar (180 systems/2335 points) and non-polar or weakly polar (307 systems/5958 points) mixtures, for which the average errors were 2.65% and 2.97%, respectively. With regard to the physical states of the systems, the average deviations achieved were 1.56% for gaseous (73 systems/1036 points), 2.90% for supercritical (173 systems/4398 points), and 2.92% for liquid (241 systems/2859 points). Furthermore, the model exhibited excellent prediction ability. Ten expressions from the literature were adopted for comparison, but provided worse results or were not applicable to polar systems. A spreadsheet for D12 Calculation is provided online for users in Supplementary Data.
J. Andrew Mccammon - One of the best experts on this subject based on the ideXlab platform.
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Fast and Accurate Calculation of Small Molecule Solvation Free Energies using Replica Exchange Accelerated Molecular Dynamics
Biophysical Journal, 2012Co-Authors: Mehrnoosh Arrar, William Sinko, Mikolai Fajer, Cesar Agusto, F. De Oliveira, J. Andrew MccammonAbstract:Free energies are important thermodynamic quantities often needed to describe chemical processes and protein-ligand binding. Accurate Calculation of free energies has been done using molecular dynamics (MD) simulations, but these values are often limited due to the conformational “trapping” of a given system in a free energy minimum. Accelerated molecular dynamics (aMD) is a hamiltonian-modifying method in which the sampling problem is mitigated by adding a bias to the potential energy term, making it easier to traverse the conformational landscape. By coupling this method with replica exchange (REXAMD), it is further enhanced, evading the statistical re-weighting problem. We show that REXAMD is ideal for computing Accurate solvation free energies of small molecules.
