Propagation of guided waves in a solid rod surrounded by infinite media is an interesting research topic of practical importance. One important application is ultrasonic nondestructive evaluation (NDE) of rock bolts. Rock bolts are inserted into the mixture of rock and concrete to ensure the stability of the groundwork. For this research topic, it is important to study the propagation of guided...

A simple method for fabrication of highly ordered gold nanorod film is introduced in this article. The procedure is based on thermal evaporation of gold into a porous anodic alumina film (PAA). The PPA film was fabricated by combining the hard and mild anodization. This combination effectively decreases the processing time of fabrication of highly ordered porous anodic alumina film with c...

Porous silicon was successfully prepared using metal-assisted chemical etching method. The Effect of HF/H2O2 concentration in etching solution as an affecting parameter on the prepared porosity type and size was investigated. Field emission electron microscopy (FE-SEM) confirmed that all etched samples had porous structure and the sample which was immersed into HF/H2O2 withmolar ratio of 7/3.53...

In the present paper, we have studied MHD free convective two dimensional unsteady viscous incompressible flows through a porous effect bounded by an infinite vertical porous plate with constant suction. The permeability of the porous medium fluctuates in time about a constant mean, and the viscosity of fluid is assumed to vary as a linear function of temperature. The flow is permitted under th...

Porous silicon layers have been prepared from n-type silicon wafers of (100) orientation. SEM, FTIR and PL have been used to characterize the morphological and optical properties of porous silicon. The influence of varying etching time in the anodizing solution, on structural and optical properties of porous silicon has been investigated. It is observed that pore size increases with etching tim...

The structural and electronic properties of the hydrogenated porous graphene nanoribbons were studied by using density functional theory calculations. The results show that the hydrogenated porous graphene nanoribbons are energetically stable. The effects of ribbon type and ribbon width on the electronic properties of these nanoribbons were investigated. It was found that both armchair and zigz...

Introduction: In contemporary THA there are two broad approaches to acetabular cup design and materials. One is an all-polyethylene design with polymethylmethacrylate (PMMA) cement. PMMA possesses a modulus of elasticity of about 2 GPa, which is between that of trabecular and subchondral bone. The second more popular approach, especially for active, younger patients, is the porous metal-backed ...

We review some of our recent efforts in developing upscaling methods for simulating the flow transport through heterogeneous porous media. In particular, the steady flow transport through highly heterogeneous porous media driven by extraction wells and the flow transport through unsaturated porous media will be considered. Mathematics subject classification: 65F10, 65F30.

Porous Pt-Ni-P composite nanotube arrays (NTAs) on a conductive substrate in good solid contact are successfully synthesized via template-assisted electrodeposition and show high electrochemical activity and long-term stability for methanol electrooxidation. Hollow nanotubular structures, porous nanostructures, and synergistic electronic effects of various elements contribute to the high electr...