Small angle X-ray scattering (SAXS) is used for low resolution structural characterization of proteins often in combination with other experimental techniques. After briefly reviewing the theory of SAXS we discuss computational methods based on 1) the Debye equation and 2) Spherical Harmonics to compute intensity profiles from a particular macromolecular structure. Further, we review how these ...

The classical time-dependent drift-diffusion model for semiconductors is considered for small scaled Debye length (which is a singular perturbation parameter multiplying the Laplace operator in the Poisson equation). The corresponding limit is carried out on both the dielectric relaxation time scale and the diffusion time scale. The latter is a quasineutral limit and the former can be interpret...

We develop a theory for Casimir-Lifshitz and Casimir-Polder interactions with semiconductor or insulator surfaces that takes into account charge drift in the bulk material through use of the classical Boltzmann equation. We derive frequency-dependent dispersion relations that give the usual Lifshitz results for dielectrics as a limiting case and, in the quasistatic limit, coincide with those re...

X-ray diffraction studies of face-centered-cubic metallic nanoparticles with different morphologies are discussed based on the experimental data and the calculation of the Debye equation with the truncated and perfect strain models. At least four basic morphologies frequently observed in face-centered-cubic metallic nanoparticles, namely sphere, cube, decahedron, and icosahedron, can be clearly...

calculate some thermodynamic properties of molten polymers including specific volume and isothermal compressibility (s.m. hoseini, physical chemistry & electrochemistry, 2 (2014) 56-65). this work extended that eos to predict the volumetric properties of some molten ethylene copolymers including ethylene/1-octene, ethylene/1-butene (xethylene equal to 0.8543 and 0.563), ethylene/propene. the ab...

Like-charged macromolecules repel in electrolyte solutions that contain small (i.e. point-like) monovalent coand counterions. Yet, if the mobile ions of one species are spatially extended instead of being point-like, the interaction may turn attractive. This effect can be captured within the mean-field Poisson-Boltzmann framework if the charge distribution within the spatially extended ions is ...

Kinetic and hyperbolic equations contain small scales (mean free path/time, Debye length, relaxation or reaction time, etc.) that lead to various different asymptotic regimes, in which the classical numerical approximations become prohibitively expensive. Asymptotic-preserving (AP) schemes are schemes that are efficient in these asymptotic regimes. The designing principle of AP schemes are to p...

This paper is concerned with the analysis of a mathematical model arising in plasma physics, more specifically in fusion research. It directly follows [17], where the tri-dimensional analysis of a Vlasov-Poisson equation with finite Larmor radius scaling was led, corresponding to the case of ions with massless electrons whose density follows a linearized Maxwell-Boltzmann law. We now consider t...