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We are outlining our most recent findings, covering: 1) A comparison of a micro- and macroscopic solution of a two-phase Riemann problem obtained from molecular dynamics simulations and finite volume schemes; 2) A novel equation of state for the bulk viscosity of liquid noble gases based on a multi-mode relaxation ansatz; 3) A detailed analysis of the evaporation process of simple fluids; 4) Diffusion coefficients of quaternary liquid mixtures obtained with the Green-Kubo formalism; 5) An analysis of the solid/fluid phase transition for the face centered cubic (fcc) lattice; 6) The relative permittivity of mixtures of water and acetone; 7) An assessment of the reliability and reproducibility of molecular simulation results; 8) Techniques for the data management in simulation workflows, including annotations of simulation outcomes with appropriate metadata standardized by an ontology.

We study different ethanol mixtures using classical molecular dynamics computer simulations. The theory of fluctuations, developed by Kirkwood and Buff in the 50's [1], allows us to connect integrals of radial distribution functions, obtained through simulations, with a variety of thermodynamic quantites, such as partial molar volumes, compressibility and most importantly, the thermodynamic factor. The value of thermodynamic factor is twofold. Firstly, it is an indicator of the stability of a mixture, with respect to mixing or demixing, since it can be written as a second derivative of the Gibbs free energy with respect to concentration. Secondly, it is particularly useful in comparing experimental and simulation results for diffusion coefficients. Here, we look for the most precise and accurate ways of calculating the thermodynamic factor from finite size systems and see what we can learn about hydrogen bonding associative mixtures and their deviation from ideality. Understanding the structural characteristics on molecular level is important for the understanding of more complex biological structures and processes. [1] JG Kirkwood, F Buff (1951) J. Chem. Phys. 19, 774

Der vorliegende Übersichtsartikel berichtet über Fortschritte in der molekularen Modellierung und Simulation mittels massiv-paralleler Hoch- und Höchstleistungsrechner (HPC). Im SkaSim-Projekt arbeiteten dazu Partner aus der HPC-Community mit Anwendern aus Wissenschaft und Industrie zusammen. Ziel dabei war es mittels HPC-Methoden die Vorhersage von thermodynamischen Stoffdaten in Bezug auf Effizienz, Qualität und Zuverlässigkeit weiter zu optimieren. In diesem Zusammenhang wurden verschiedene Themen bearbeitet: Atomistische Simulation der homogenen Gasblasenbildung, Oberflächenspannung klassischer Fluide und ionischer Flüssigkeiten, multikriterielle Optimierung molekularer Modelle, Weiterentwicklung der Simulationscodes ls1 mardyn und ms2, atomistische Simulation von Gastrennprozessen, molekulare Membran-Strukturgeneratoren, Transportwiderstände und gemischtypenspezifische Bewertung prädiktiver Stoffdatenmodelle.

We present deep near-infrared (K_s) images and surface photometry for 80 dwarf irregular galaxies (dIs) within ~5 Mpc of the Milky Way. The galaxy images were obtained at five different facilities between 2004 and 2006. The image reductions and surface photometry have been performed using methods specifically designed for isolating faint galaxies from the high and varying near-infrared sky level. Fifty-four of the 80 dIs have surface brightness profiles which could be fit to a hyperbolic-secant (sech) function, while the remaining profiles could be fit to the sum of a sech and a Gaussian function. From these fits, we have measured central surface brightnesses, scale lengths, and integrated magnitudes. This survey is part of a larger study of the connection between large-scale structure and the global properties of dIs, the hypothesized building-blocks of more massive galaxies.

We present deep near-infrared (K_s) images and surface photometry for 80 dwarf irregular galaxies (dIs) within ~5 Mpc of the Milky Way. The galaxy images were obtained at five different facilities between 2004 and 2006. The image reductions and surface photometry have been performed using methods specifically designed for isolating faint galaxies from the high and varying near-infrared sky level. Fifty-four of the 80 dIs have surface brightness profiles which could be fit to a hyperbolic-secant (sech) function, while the remaining profiles could be fit to the sum of a sech and a Gaussian function. From these fits, we have measured central surface brightnesses, scale lengths, and integrated magnitudes. This survey is part of a larger study of the connection between large-scale structure and the global properties of dIs, the hypothesized building-blocks of more massive galaxies.

We are outlining our most recent findings, covering: 1) A comparison of a micro- and macroscopic solution of a two-phase Riemann problem obtained from molecular dynamics simulations and finite volume schemes; 2) A novel equation of state for the bulk viscosity of liquid noble gases based on a multi-mode relaxation ansatz; 3) A detailed analysis of the evaporation process of simple fluids; 4) Diffusion coefficients of quaternary liquid mixtures obtained with the Green-Kubo formalism; 5) An analysis of the solid/fluid phase transition for the face centered cubic (fcc) lattice; 6) The relative permittivity of mixtures of water and acetone; 7) An assessment of the reliability and reproducibility of molecular simulation results; 8) Techniques for the data management in simulation workflows, including annotations of simulation outcomes with appropriate metadata standardized by an ontology., The co-authors M.H., R.S.C., S.H., G.G.-C., R.F., M.K., S.S. and J.V. acknowledge funding by Deutsche Forschungsgemeinschaft (DFG) through the Project SFB-TRR 75, project number 84292822: D��roplet Dynamics under Extreme Ambient Conditions,�� and the co-author M.T.H. acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no. 760907 (VIMMP). This work was carried out under the auspices of the Boltzmann-Zuse Society of Computational Molecular Engineering (BZS), and it was facilitated by activities of the Innovation Centre for Process Data Technology (Inprodat e.V.), Kaiserslautern. The simulations were performed on the CRAY XC40 (Hazel Hen) at the High Performance Computing Center Stuttgart (HLRS).

We are outlining our most recent findings, covering: 1) A comparison of a micro- and macroscopic solution of a two-phase Riemann problem obtained from molecular dynamics simulations and finite volume schemes; 2) A novel equation of state for the bulk viscosity of liquid noble gases based on a multi-mode relaxation ansatz; 3) A detailed analysis of the evaporation process of simple fluids; 4) Diffusion coefficients of quaternary liquid mixtures obtained with the Green-Kubo formalism; 5) An analysis of the solid/fluid phase transition for the face centered cubic (fcc) lattice; 6) The relative permittivity of mixtures of water and acetone; 7) An assessment of the reliability and reproducibility of molecular simulation results; 8) Techniques for the data management in simulation workflows, including annotations of simulation outcomes with appropriate metadata standardized by an ontology.