This paper discusses the modeling of unsteady-state mass diffusion under concentrationdependent diffusivity through an orthotropic medium. Historically, a simpler one-dimensional formulation with constant medium properties has been used, leading to approximate solutions. The present work uses a finite element formulation with finite difference discretization in time. The code includes an elemen...

double-diffusive mixed convection in a lid-driven square enclosure filled with al2o3-water is numerically investigated. two-dimensional nonlinear governing equations are discretized using the control volume method and hybrid scheme. the equations are solved using simpler algorithm. the results are displayed in the form of streamlines, isotherms, and iso-concentrations when the richardson number...

3 Introduction and Background 5 Methods 6 Results and Discussion 10 Tortuosity 18 Pore-Bond Network Represenations 22 Comparison between Commercial and Laboratory Sheets 28 Permeability 31 Effect of papermaking processes on 3D structure 33 Comparison of high and low resolution tomography 37 Surface Structure Characterization 42 Method to predict transport properties using actual 3D structures 4...

Transdermal patches were developed for a low oral bioavailable drug, lacidipine (LCDP) employing ethyl cellulose/Eudragit RL100 and polyvinyl pyrollidone (PVP) as polymeric matrices. The effect of binary mixtures of polymers on physicochemical properties such as thickness, moisture absorption and moisture content; in vitro release, ex vivo permeation and mechanical properties was evaluated. Ex ...

We propose an advanced thermal-moisture analogy scheme to cope with the inherent limitations of the existing analogy schemes. The new scheme is based on the experimentally observed unique hygroscopic behavior of polymeric materials used in microelectronics; i.e., the saturated concentration is only a function of relative humidity regardless of temperature. A new analogy formulation based on the...

The relatively high permittivity of liquid water compared to other materials in the Terahertz (THz) range enables a contrast mechanism for the detection and imaging of moisture. In this paper, spatial mapping of moisture and liquid detection by THz imaging is reviewed. Analysis of the moisture content is discussed in terms of a double Debye model for liquid water and effective medium models for...

Equilibrium moisture contents (EMCs) and diffusion coefficients of a high pressure laminate (HPL) overlay, a wood particleboard (PB) substrate, and an HPL backer (BCK) were measured at different levels of relative humidity (RH). The EMCs as a function of RH were fitted to the Nelson's sorption isotherm. It was found that Nelson's model reproduced accurately the experimental data of these differ...

Moisture control is an important part of effective maintenance program for gas-insulated switchgear (GIS). Herein, hexagonal mesoporous silica (HMS) materials were synthesized by adopting dodecylamine as a structure directing agent, which was then employed as a host for supporting polyethylenimine (PEI) without further calcinations or extraction treatment. The physicochemical properties of the ...