Augmented reality (AR) provides huge opportunities for online teaching in science and engineering, as these disciplines place emphasis on practical training and unsuited to completely nonclassroom training. This paper proposes a new concept in virtual and remote laboratories: the augmented remote laboratory (ARL). ARL is being tested in the first and second years of the new degrees in industrial engineering and computer engineering, respectively, at the School of Engineering, University of Huelva, Huelva, Spain. By means of augmented reality techniques, ARL allows the student to experience sensations and explore learning experiences that, in some cases, may exceed those offered by traditional laboratory classes. The effectiveness of this methodology for remote laboratory work is evaluated by comparing it to practical sessions in the laboratory at the university itself with the same group of students. Students completed a questionnaire after having experienced both types of practicals, and the results show that the use of ARL improves student outcomes. As discussed in the paper, the potential of AR to configure different experiments from the same physical configuration is virtually limitless.
28 February 2014 in Industrial & Engineering Chemistry Research
We present a corresponding states correlation based on the description of fluid phase properties by means of an Mie intermolecular potential applied to tangentially bonded spheres. The macroscopic properties of this model fluid are very accurately represented by a recently proposed version of the Statistical Associating Fluid Theory (the SAFT-γ version). The Mie potential can be expressed in a conformal manner in terms of three parameters that relate to a length scale, σ, an energy scale, ε, and the range or functional form of the potential, λ, while the nonsphericity or elongation of a molecule can be appropriately described by the chain length, m. For a given chain length, correlations are given to scale the SAFT equation of state in terms of three experimental parameters: the acentric factor, the critical temperature, and the saturated liquid density at a reduced temperature of 0.7. The molecular nature of the equation of state is exploited to make a direct link between the macroscopic thermodynamic parameters used to characterize the equation of state and the parameters of the underlying Mie potential. This direct link between macroscopic properties and molecular parameters is the basis to propose a top-down method to parametrize force fields that can be used in the coarse grained molecular modeling (Monte Carlo or molecular dynamics) of fluids. The resulting correlation is of quantitative accuracy and examples of the prediction of simulations of vapor–liquid equilibria and interfacial tensions are given. In essence, we present a recipe that allows one to obtain intermolecular potentials for use in the molecular simulation of simple and chain fluids from macroscopic experimentally determined constants, namely the acentric factor, the critical temperature, and a value of the liquid density at a reduced temperature of 0.7.
The SAFT-γ coarse graining methodology (Avendaño et al., 2011) is used to develop force fields for the fluid-phase behaviour of binary and ternary mixtures comprising water, carbon dioxide, and n-alkanes. The effective intermolecular interactions between the coarse grained (CG) segments are directly related to macroscopic thermodynamic properties by means of the SAFT-γ equation of state for molecular segments represented with the Mie (generalised Lennard–Jones) intermolecular potential (Papaioannou et al., 2014). The unlike attractive interactions between the components of the mixtures are represented with a single adjustable parameter, which is shown to be transferable over a wide range of conditions. The SAFT-γ Mie CG force fields are used in molecular-dynamics simulations to predict the challenging (vapour+liquid) and (liquid+liquid) fluid-phase equilibria characterising these mixtures, and to study phenomena that are not accessible directly from the equation of state, such as the interfacial properties. The description of the fluid-phase equilibria and interfacial properties predicted with the SAFT-γ Mie force fields is in excellent agreement with the corresponding experimental data, and of comparable if not superior quality to that reported for the more sophisticated atomistic and united-atom models