Porous silicon multilayers and microcavities, prepared by the pulsed electrochemical etching method, exhibit a variety of reflectivity and photoluminescence spectra. A comparison of the measured results with those calculated based on the transfer matrix method and quantum-box model reveals that the variation of the spectra can be attributed to the change in wavelength position of the stop-band ...

in this paper, fluid flow between two parallel flat plates that are partially filled with two-dimension porous media is investigated numerically using single relaxation time (srt) lattice boltzmann method (lbm) at pore scale. the considered obstacles are random, circular, rigid and granular with uniform diameters. single component and single-phase viscous newtonian fluid are considered as worki...

in oil industry, spontaneous imbibition is an important phenomenon in recovery from fractured reservoirs which can be defined as spontaneous uptake of a wetting fluid into a porous solid. spontaneous imbibition involves both cocurrent and countercurrent flows. when a matrix block is partially covered by water, oil recovery is dominated by cocurrent imbibition i.e. the production of non wetting ...

In this study, the thermal performance analysis of porous fin with temperature-dependent thermal conductivity and internal heat generation is carried out using Haar wavelet collocation method. The effects of various parameters on the thermal characteristics of the porous fin are investigated. It is found that as the porosity increases, the rate of heat transfer from the fin increases and the th...

In this study buckling analysis of solid rectangular plate made of porous material in undrained condition is investigated. The mechanical properties of plate are assumed to vary through the thickness direction. Distributing of the pores through the plate thickness are assumed to be the nonlinear nonsymmetric, nonlinear symmetric, and monotonous distribution. The effect of pores and pores distri...

This paper presents a method for the fabrication of integrated porous silica layers in microfluidic channel networks by microfabrication techniques. Porous silica is obtained by anodization of silicon, followed by full conversion of the porous silicon network into porous silica by means of thermal oxidation. A series of experiments were performed with various channel layouts to determine the cr...

Porous materials are widely used for improving sound absorption and sound transmission loss of vibrating structures. However, their efficiency is limited to medium and high frequencies. A common solution for improving their low frequency behavior while keeping an acceptable thickness is to embed resonant structures such as Helmholtz resonators. This work investigates the absorption and transmis...

Herman Helmholz had his pupil Zahnz construct a filter out of a porous porcelain cylinder, and this form of apparatus was also used by Kehrer.3 Hermann modified Zahn’s method and used powdered porous plate to adsorb the casein. Tiemann, however, several years later made extensive use of a method devised by Lehmann,c in which the milk was placed upon a slightly concave, porous plate, whose surfa...

Biocompatibility testing of differently structured titanium implants was performed using an in vitro test system of a newly established human fetal osteoblastic cell line (hFOB 1.19). Cell adhesion of osteoblastic cells on the different porous geometries and the suitability of a copper vapor laser system for surface structuring was tested with the following parameters: cell-number, cell viabili...

This article explores the applicability of numerical homogenization techniques for analyzing transport properties in real foam samples mostly open-cell, to understand long-wavelength acoustics of rigid-frame air-saturated porous media, on the basis of microstructural parameters. Experimental characterization of porosity and permeability of real foam samples are used to provide the scaling of a ...