Search results for "computer simulations"
showing 9 items of 9 documents
Flexible power converters for the fault tolerant operation of Micro-Grids
2010
The progressive penetration level of Distributed Generation (DG) is destined to cause deep changes in the existing distribution networks no longer considered as passive terminations of the whole electrical system. A possible solution is the realization of small networks, namely the Micro-Grids, reproducing in themselves the structure of the main production and distribution of the electrical energy system. In order to gain an adequate reliability level of the microgrids the individuation and the management of the faults with the goal of maintaining the micro-grid operation (fault tolerant operation) is quite important. In the present paper flexible power converters and a companion control al…
Experimental and theoretical studies of Stark profiles of Ar I 696.5 nm spectral line in laser-induced plasma
2019
Abstract We report the results of the Stark profile studies of the 696.543 nm Ar I spectral line in laser-induced plasma generated by a nanosecond Nd:YAG laser radiation at 532 nm in argon at reduced pressure. Plasma diagnostics was performed with the use of the laser Thomson scattering method, free from assumptions about the plasma thermodynamic equilibrium, its composition but also independently of plasma emission spectra. The profiles were investigated in wide range of electron densities and temperatures, from 2.81 · 1022 m − 3 to 5.69 · 1023 m − 3 and from 10 430 K to 73 400 K, respectively. Stark profiles were calculated using a semi-classical method as well as by N-body numerical simu…
Time evolution of size and polydispersity of an ensemble of nanoparticles growing in the confined space of AOT reversed micelles by computer simulati…
2005
The time dependence of size and polydispersity of an ensemble of nanoparticles growing in the confined space of water-containing AOT reversed micelles has been investigated by computer simulations. It has been found that, in a wide time range, the mean nanoparticle size can be described by power laws whose exponent is critically dependent on the efficiency of the intermicellar material exchange process while the nanoparticle polydispersity increases with time. From the analysis of all the disentangled effects arising from the variation of internal and external parameters provided by simulations, useful suggestions for a better and rationale control of the nanoparticle synthetic procedure ar…
Understanding and Controlling Food Protein Structure and Function in Foods: Perspectives from Experiments and Computer Simulations
2020
The structure and interactions of proteins play a critical role in determining the quality attributes of many foods, beverages, and pharmaceutical products. Incorporating a multiscale understanding of the structure–function relationships of proteins can provide greater insight into, and control of, the relevant processes at play. Combining data from experimental measurements, human sensory panels, and computer simulations through machine learning allows the construction of statistical models relating nanoscale properties of proteins to the physicochemical properties, physiological outcomes, and tastes of foods. This review highlights several examples of advanced computer simulations at mol…
A computational study of point defects and diffusion in enstatite
2009
In order to contribute to the understanding of diffusion processes in enstatite (Mg2Si2O6), we have used atomistic simulation techniques to study point defects in this mineral. We present results for a variety of Scottky and Frenkel defects of all atomic species present in it. We have furthermore calculated the activation energy for magnesium diffusion. We break diffusion down into a succession of hops between neighboring sites. Each hop is associated with a migration energy barrier. By making a series of hops, the diffusing ion may cross the unit cell. The maximum migration energy necessary to attain movement in a direction is the activation energy for diffusion in that direction. The defe…
Density functional/molecular dynamics simulations of phase-change materials
2013
Best Practices in Constant pH MD Simulations: Accuracy and Sampling
2022
Various approaches have been proposed to include the effect of pH in molecular dynamics (MD) simulations. Among these, the λ-dynamics approach proposed by Brooks and co-workers [Kong, X.; Brooks III, C. L. J. Chem. Phys.1996, 105, 2414−2423] can be performed with little computational overhead and hfor each typeence be used to routinely perform MD simulations at microsecond time scales, as shown in the accompanying paper [Aho, N. et al. J. Chem. Theory Comput.2022, DOI: 10.1021/acs.jctc.2c00516]. At such time scales, however, the accuracy of the molecular mechanics force field and the parametrization becomes critical. Here, we address these issues and provide the community with guidelines on…
Water effects on trehalose matrices studied through Molecular Dynamics
2012
Computer Simulations of the Band Structure and Density of States of the Linear Chains of NaCl Ions
2019
The authors thank Eugene Kotomin and V. Kuzovkov for fruitful discussions and valuable suggestions. A.I.P thanks A.Moskina for the technical assistance in preparation of the manuscript. A.I.P also gratefully acknowledges a project LZP-2018/1-0214 from the Latvian Council of Science for partial support.