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Engineering education is being called upon to move to a student-centered teaching. New challenges demand a curriculum that considers a set of competencies to enable engineers to learn autonomously and to develop solid technical and relevant soft skills. We present a top-down methodology for developing a competency-based curricula, which was employed to conceive a new chemical engineering curriculum at the University of Campinas. Our methodology is based on four main steps: i) definition of the desired profile of students with a bachelor's degree in Chemical Engineering and their underlying competencies; ii) delineation of learning-experiences itineraries; iii) a macro conception of the curriculum entailing the logical-temporal arrangement of its learning-experiences itineraries; and the iv) establishment of each curricular component with its learning objectives. This new curriculum is integrated into the external society by experiences that engage students to practice social responsibility and develop technology based on the needs of society. Graduates' profile and competencies were defined based on extensive surveys. We discuss how active learning methodologies can be an intrinsic part of the curriculum development process and how assessment strategies must fit the learning goals established for each curricular component. Finally, we discuss the current challenges of implementing and evaluating a competency-based curriculum. [Display omitted] • We present a top-down methodology for developing a competency-based curricula. • Design of the new chemical engineering curriculum at the University of Campinas. • The graduate's profile and competencies were defined based on extensive surveys. • Discussion of challenges of implementing/ evaluating a competency-based curriculum. [ABSTRACT FROM AUTHOR]

Abstract All fluids are somehow confined; even the ideal gas is by definition a confined fluid model. For all practical purposes, if the distance between the confining walls is reasonably large, the confinement effect is negligible. Nevertheless, whenever this distance is about a few nanometers, the confinement effect is unavoidable, and is manifested as an inhomogeneity in the fluid particles distribution. Here, a statistical mechanical framework from which the structure of a confined ideal gas can be directly calculated is derived. As a case study, the structure of an ideal gas confined by planar graphite walls is determined with the proposed theory and compared to Monte Carlo simulations. The gratifyingly perfect agreement between these two approaches shows the correctness of the proposed theory. The influences of pore size and temperature are analyzed. The theoretical results obtained here serve as a limit that is obeyed by any low density confined fluid. [ABSTRACT FROM AUTHOR]

Abstract: A new model to describe the solubility of amino acids and β-lactam compounds as a function of pH is proposed. The description of the solid–liquid equilibrium entails simultaneous calculation of phase and chemical equilibria. The liquid-phase non-ideality was accounted for through an extended Pitzer model for polyelectrolyte solutions. A statistical thermodynamic interpretation of Pitzer's binary interaction parameters is also presented. The model was successfully applied to different systems containing amino-acids, as well as glycine and its oligopeptides and β-lactam compounds such as ampicillin and 6-aminopenicillanic acid. [Copyright &y& Elsevier]

Dipalmitoylphosphatidylcholine is a phospholipid of major importance for biological systems. Molecular dynamics simulation investigations of this lipid focused on their behavior at human body temperature (≈ 37 °C or 310 K). For some applications, however, it is necessary to study its properties at room temperature (≈ 25 °C or 298 K). A small difference in temperature at this range is responsible for a phase transition in the lipid bilayer. Therefore, molecular dynamics simulations are carried out applying six different force fields from the GROMOS family to compare the less ordered phase (liquid-crystalline phase) with a more ordered phase (gel phase) of the hydrated bilayer of dipalmitoylphosphatidylcholine formed at 323 K and 298 K, respectively. The analysis of the bilayer structural quantities is used to evaluate order and packing at the two temperatures. The area per lipid and deuterium order parameter results are in agreement with simulation results from the literature and are also compared with experimental data. These parameters, however, do not provide a clear picture of the low-temperature gel phase present in the simulations using the force fields from the GROMOS family. To address this, a strategy for computing the lipid phase nematic order parameter is proposed, and a reference gel phase is simulated using the CHARMM36 force field for comparison. The results are consistent with other structural quantities but reveal a level of order that is below the expected for an ordered gel phase for the GROMOS force fields. Visual inspection of the simulation trajectories suggests the presence of a ripple phase. Overall, the GROMOS 54A8 provides the best performance among the tested GROMOS force fields for both investigated temperatures, even lacking a proper representation of the ordered gel phase. [Display omitted] • Among the GROMOS family, 54A8 is the one that provides the best agreement with the APL and deuterium order parameter experimental data for DPPC bilayer. • None of the force fields from GROMOS family reproduce the structure expected for DPPC bilayers at 298 K. • The nematic order parameter seems to be a more adequate quantity to evaluate lipid bilayer phase. [ABSTRACT FROM AUTHOR]

The application of classical density functional theory (cDFT) to model confined fluids is an outstanding example of directly using fundamental scientific knowledge, such as Statistical Mechanics, to calculate both structural fluid information and macroscopic physical properties needed for process design. One of the goals of this work is to provide materials that allow the reader to become familiar with cDFT. To do that, we present the fundamentals of cDFT and provide sample computational codes that apply its concepts to simple cases. A second goal is to present some of the modern applications of cDFT and related techniques, such as the multicomponent potential theory of adsorption and the development of specialized equations of state for confined fluids, as well as to review publicly available cDFT computer libraries. Overall, there has been a remarkable number of successful applications, ranging from ideal gases confined in 1D geometries to fluids modeled by modern equations of state in 3D porous solids. At the same time, some challenges remain. For example, most implementations are based on grand-potential formulations, which are not always the most convenient for process design. Further, additional results of heat of adsorption predictions would be useful because of their importance in equipment design. Another intriguing alternative could be integrating information from quantum DFT software simulations as input for classical DFT simulations. [Display omitted] • Classical density functional theory (cDFT) yields structural data of confined fluids. • cDFT allows the combination of virtually any equation of state and external potential. • Currently, cDFT's most notable application is in the characterization of adsorbents. • As computer speeds increase, cDFT's use for process design will likely increase. [ABSTRACT FROM AUTHOR]

Perturbation theory has been the center of the development of the new generation of equations of state. First- and second-order perturbation theories are very common, but require approximations for obtaining an analytical form. Recently, a new equation of state has been proposed in which the reference fluid is based on the hard Gaussian overlap approach, and the perturbed potential is defined as a spherically symmetric square well. In such an approach, the first- and second-order coefficients were considered the same as the ones applied for a system in which the reference term is spherical. Using Monte Carlo simulations, we investigated the validity of such an approximation by calculating the first- and second-order coefficients of the high-temperature expansion series of the Helmholtz free energy. With our findings, this approximation seems to be quite reasonable for a certain range of anisotropies. We also present a calculation of the perturbed molar Helmholtz free energy using Monte Carlo simulations, which could in principle be used for improving the equation of state. [ABSTRACT FROM AUTHOR]