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Transports and sound absorption performance of foam-based absorbers are influenced by the morphologies of their pore connections. Understanding the microstructure–property relationships of sound absorbers can provide valuable insights and guidance for designing and manufacturing steps. We develop in this paper surrogate models based on the polynomial chaos expansion to predict the acoustic behavior of graded foam absorbers. Regarding the local morphology of foams, three representative factors including the porosity, the cell size, and the membrane closure ratio are considered through a periodic unit cell. Then, the reference maps of transport properties are computed via the hybrid numerical method based on the homogenization technique, surrogates are consequently generated in the designing space involving the morphology features. Finally, after evaluating their convergence characteristics and verification study, the surrogate models are adopted to study foam layers within different graded characteristics. Within a tolerance error, the surrogate models of transport properties offer advantages in terms of the computational efficiency and predictability. Both surrogate model-based investigation and optimization frameworks allow estimating the local morphology factors where the desired sound absorption properties of the graded foam absorbers can be achieved. [ABSTRACT FROM AUTHOR]

• Crystallographic orientation-dependence of Cu dissolution/deposition on Cu (100), (110) and (111) faces. • Cu(110) surface shows the strongest anti-corrosion ability under any applied charge levels, while it is the easiest surface for Cu deposition. • Contributing factors: the number of bonds and the largest enhancements on electron density between Cu adsorbates and adsorbent. • A method to quickly screen metal surfaces with the strongest anti-corrosion capabilities is proposed. The corrosion protection of metallic materials is essential and necessary for their applications in various areas. The corrosive behavior of a metal in an environment is affected by a variety of elements, including crystal faces. The current study investigates the crystallographic orientation dependence of Cu dissolution/deposition on the (110), (100) and (111) faces of an electrolyte-immersed single-crystal Cu electrode. The face-dependent dissolution/deposition and the influence of the applied charge are investigated with a combination of first-principles and continuum calculations. The calculations show that the Cu(110) surface has the best anti-corrosion performance and is the easiest for Cu deposition among all applied charge levels. This is because electron density increases between Cu adsorbates and the electrode. Based on our calculations, the Cu(110) face shows intrinsic corrosion resistance in a non-corrosive electrolyte that is free of passive layer, inhibitors or reactive ions. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen vacancy (V O) defect is an essential origin of bias stability in oxide TFT devices. • Common measurement methods are not sufficient to accurately quantify Vo concentration (n Vo) in amorphous In-Ga-Zn-O (a-IGZO). • V O tends to capture H atoms to increase their migration energy barriers. • Simulated hydrogen diffusion in a-IGZO is used to evaluate n Vo. A multiscale approach is presented to calculate the hydrogen diffusion in amorphous In-Ga-Zn-O (a-IGZO). Based on the fact that the presence of oxygen vacancy (V O) defects suppresses the hydrogen diffusion in a-IGZO, the simulated H diffusion depth is utilized to evaluate the V O concentration (n Vo). The kinetic Monte Carlo (kMC) simulation is carried out to obtain the depth profiles of H diffusion in a-IGZO, which uses input of the H migration energy barriers (E A) calculated within the density functional theory (DFT) method. The DFT calculations showed that when H occupies the V O defects, its E A becomes higher than that of the interstitial H, which eventually suppresses H diffusion. The H diffusion function depending on n Vo and temperature, f D (n Vo , T), is readily obtained fitting the complementary error function to the simulated H diffusion profile. It is observed that f D (n Vo , T) can closely reproduce the experimentally measured H diffusion from literature with n Vo being comparable to the measured carrier concentration that can be speculated as the upper limit of n Vo. The properties of H diffusion in a-IGZO are examined in detail to address the application of the presented approach for estimation of n Vo. [ABSTRACT FROM AUTHOR]

• Coarse-Grain MARTINI Molecular Dynamics simulations of PEDOT:Tos are conducted. • A general backmapping method is applied to retrieve the All-Atom representation. • The backmapping corrects the structural artifacts induced by the Coarse-Graining. • The calculated holes mobility on backmapped volume compare well with previous studies. • The workflow Coarse-Grain -> Backmapping -> Mobility calculation is fully validated. Designing new high performances materials based on conducting polymers necessitates the development of multiscale models to investigate the charge transport in large realistic systems. In this work, we utilize Coarse-Grained (CG) Molecular Dynamics (MD) simulations to generate morphologies of Poly(3,4-ethylenedioxythiophene) (PEDOT) doped with Tosylate (TOS) ions, and we develop a backmapping protocol to retrieve the atomistic details of the molecules afterwards. We demonstrate that the proposed protocol corrects for the nanostructure distortions induced by Coarse-Graining the system, namely a wrong density and an over-estimated π - π stacking distance. Quantum chemical calculations are performed on the systems obtained after backmapping in order to calculate hopping rates for charge transport, and charge mobilities as a function of the PEDOT chain length and hydration level are then calculated by solving a master equation for transport. The results are identical to the calculations performed on PEDOT morphologies obtained by direct All-Atomistic (AA) MD simulations: the mobility increases with the chain length and decreases with the hydration level, this last effect being more pronounced for short chains. This definitely shows that the workflow CG MD → backmapping → mobility calculations is in position to calculate charge mobility in PEDOT based materials, paving the way for theoretical investigations of transport in more complex materials such as PEDOT doped with Polystyrene Sulfonate (PSS). [ABSTRACT FROM AUTHOR]