In the present study, we propose a novel extended population balance equation (PBE) model for aggregation and sintering couple it with computational fluid dynamics (CFD) to investigate synthesis of silica nanoparticles in laminar diffusion flame. The PBE includes finite-rate primary particles by solving together transport number concentration particles. process simulated, are formed via oxidati...

Density functional theory (DFT) has become the method of choice for many applications of quantum mechanics to the study of the electronic properties of molecules and solids. Despite the enormous progress in improving the functionals, the current generation is inadequate for many important applications. As part of the quest of finding better functionals, we consider in this paper the Perdew-Burk...

Continuum electrostatics methods have become increasingly popular due to their ability to provide approximate descriptions of solvation energies and forces without expensive sampling required by explicit solvent models. In particular, the Poisson-Boltzmann equation (PBE) provides electrostatic potentials, solvation energies, and forces by modeling the solvent as a featureless, dielectric materi...

Vacancies in graphene present sites of altered chemical reactivity and open possibilities to tune graphene properties by defect engineering. The understanding of chemical reactivity of such defects is essential for successful implementation of carbon materials in advanced technologies. We report the results of a systematic DFT study of atomic adsorption on graphene with a single vacancy for the...

Melanogenesis is the physiological process by which melanin is synthesized to protect the skin from UV damage. While paracrine interactions between keratinocytes and melanocytes are crucial for regulating epidermal pigmentation, the endothelin (EDN)-endothelin B-receptor (EDNRB) interaction is one of the key linkages. In this study, we found that a single exposure of normal human melanocytes (N...

We have examined the performance of a variety of density functional theory procedures for the calculation of complexation energies and proton-exchange barriers, with a focus on the Minnesota-class of functionals that are generally highly robust and generally show good accuracy. A curious observation is that M05-type and M06-type methods show an atypical decrease in calculated barriers with incr...

We study the problem of efficiently predicting a correct program from a large set of programs induced from few input-output examples in Programming-byExample (PBE) systems. This is an important problem for making PBE systems usable so that users do not need to provide too many examples to learn the desired program. We first formalize the two classes of sharing that occurs in version-space algeb...

To understand the performance of popular density-functional theory exchange-correlation (xc) functionals in simulations of liquid water, water monomers and dimers were extracted from a PBE simulation of liquid water and examined with coupled cluster with single and double excitations plus a perturbative correction for connected triples [CCSD(T)]. CCSD(T) reveals that most of the dimers are unbo...

This paper is the first of two papers on the adaptive multilevel finite element treatment of the nonlinear Poisson-Boltzmann equation (PBE), a nonlinear elliptic equation arising in biomolecular modeling. Fast and accurate numerical solution of the PBE is usually difficult to accomplish, due to presence of discontinuous coefficients, delta functions, three spatial dimensions, unbounded domain, ...

Electrostatics interactions play amajor role in the stabilization of biomolecules : as such, they remain a major focus of theoretical and computational studies in biophysics. Electrostatics in solution is strongly dependent on the nature of the solvent and on the ions it contains. While methods that treat the solvent and ions explicitly provide an accurate estimate of these interactions, they a...