Volume 4 Issue 2
Authors: Haidar F. AL-Qrimli; Fadhil A. Mahdi; Firas B. Ismail
Abstract: Currently, there is demand for the utilisation of woven composites in aerospace and industrial applications, mostly due to their superior strength-to-weight ratio and thermal properties, as opposed to conventional materials. However, the mechanical behaviour of woven composites is not on par with traditional materials. The central objective of this study is to develop an understanding of three-dimensional woven composites through the improvement of accurate numerical models that are also validated with experimental results. Five specimens were fabricated using American Society for Testing and Materials (ASTM D3039) guidelines to study the mechanical performance of carbon/epoxy. The experimental tensile tests results and the finite element analysis outcomes for the carbon/epoxy composite agree with each other, with 5.05 percentages of error, which validates the numerical results.
Keywords: Composite Materials; Matrix Composite; Numerical Simulation
Authors: Hossein Ataei
Abstract: -In an air blast, building windows break into high-velocity flying shards (annealed glass windows) or fragments (fully tempered windows) that are a primary source of injury to the buildings occupants. In order to successfully design these glazing systems against air blast loading, there should be a balance between the safety and security of the window panel and considerations for the physical appearance and cost-effectiveness, based on the proposed level of security and previous lessons learned. Better understanding of the glazing systems' failure due to the blast load characteristics is an important step forward in mitigating injuries. In this paper, glass failure dynamics is studied using energy methods and brittle failure theories combined with finite element simulations and techniques. Because both methods take into account glass panel characteristics and blast load intensities, employing explicit nonlinear finite element methods with analytical energy methods to model the brittle failure of the conventional building glazing systems is the superior strategy. The results of this study will be beneficial in development of more comprehensive blast-resistance design guidelines and a glazing injury model that will enhance the security of the buildings and improve the safety of the occupants during an air blast.
Keywords: Energy Methods; Glazing Systems; Manmade Hazards; Finite Element Analysis; Safety Assessment
Authors: A. O. Osikoya; C.W. Dikio; N. Ayawei; D. Wankasi; A.S. Afolabi; E. D. Dikio
Abstract: Chorine doped carbon nanotubes (CNTs) are synthesized to introduce dipole moment into the lattice of the CNTs to enhance interaction with cationic species in adsorption. Cobalt and silver co-catalyst supported on magnesium oxide (MgO) is used as growth promoter and their morphological features were studied using Raman spectroscopy, energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) spectroscopy. Equilibrium and thermodynamic batch adsorption experiments were carried out by studying the concentration, time and temperature effects. The morphological images of the doped carbon materials showed amorphous multiwall nanotubes with some crystalline regions that are attributable to the doping of the chlorine. The adsorption studies recorded a rapid uptake of Cr3+ by the carbon nanotubes h was mainly diffusion controlled. The thermodynamic studies suggested relatively low temperature (low energy) favoured sorption was exothermic with a physic-sorption mechanism.
Keywords: Adsorption; Carbon Nanotubes; Chlorine; Synthesis