In this study, three-point bending tests were simulated to investigate the bending behaviours of honeycomb sandwich panels. The sandwich panels used in the study consisted of aluminium alloy skins and cast polyamide honeycomb core. The collapse mechanism and effects of the structural parameters of panels were investigated. The structural parameters of a honeycomb panel are foil thickness, height of core and length of cell. According to the finite element analysis results, as the foil thickness and core height of sandwich panel increase, the load-carrying capacity of the sandwich panel increases. As the length of cell edge increases, the maximum load value decreases. According to the analysis of variance test results, the most important parameter affecting the bending behaviour honeycomb panel is the height of the core (34%). The second factor is foil thickness (30.5%). The influence of the cell edge is lower than other parameters (27.2%).

In this work, a nanoemulsion-based delivery system was developed by encapsulation of different concentrations (0.50%, 0.75% and 1.00% v/v) of oregano essential oil (OEO) within poly(vinyl alcohol). The delivery systems (OEO-loaded nanoemulsion systems (NESs)) were characterized in terms of size distribution, zeta potential and thermal, molecular, microstructural and antifungal properties. The average droplet diameter values were determined to be within the range 70–75 nm, while zeta potential values within the range 3.13–19.90 mV were recorded. An increase in the OEO concentration did not affect the size distribution of nanoemulsions. Change in the concentrations showed no visible differences in Fourier transform infrared spectra. However, for concentrations of 0.50, 0.75 and 1.00%, endothermic peak temperatures were recorded as 94, 105 and 117°C, respectively. The antifungal activity of NESs against the mycelial growth of Aspergillus niger was evaluated, revealing a significant enhancement in the antifungal activity in comparison with that of free OEO. The zone diameter of mycelial growth could be reduced by around 20, 55 and 65% using NESs at levels of 0.50, 0.75 and 1.00% v/v, respectively, over 6 days of incubation. The results of this study revealed the stronger antifungal efficiency of OEO by its encapsulation into NESs as compared with that of free OEO.

Radiation has been used in many different fields since its discovery, but using it in medical applications is vital, as it is related to human health. In medical application, many different materials are used for different purposes. Three-dimensional materials are used in phantom technology, and it is important to know the properties of those materials. In this study, the linear attenuation coefficients (LACs; μ, cm−1) and some other related parameters of gamma rays (mean free path, half-value layer, tenth-value layer, effective atomic number (Zeff), electron density (Neff) and equivalent atomic number (Zeq)) were obtained for five different phantom fabrication materials used in medical dosimetry. The calculations were done using the Phy-X/PSD software for gamma energies of 10−3–105 MeV. The obtained LAC results ranged from 0.103 to 0.13 cm−1for 0.365 MeV, from 0.09 to 0.11 cm−1for 0.511 MeV and from 0.059 to 0.076 cm−1for 1.275 MeV.

In this paper, the effective coefficients of piezoelectric fiber-reinforced composites are determined through two micromechanics methods. The exact solutions are derived to predict the effective electro-elastic coefficients with modifications in the conventional strength of materials approach and strain energy approach to account for the effects of fiber packing arrangements and orientations on these properties. A representative volume element subjected to a mechanical loading in the longitudinal direction to the fiber and an electrical loading in the transverse direction to the fiber is used to model the problem mathematically and derive the results. The effective elastic, piezoelectric and dielectric coefficients are estimated by these two methods, and the results are compared with those predicted by the strength of materials method of the literature. From the results, it is observed that results obtained for the elastic, piezoelectric and dielectric coefficients by the strength of materials method and modified strength of materials method are in good agreement with each other in a useful range of fiber volume fractions, while the results obtained through the energy approach shows some deviations when compared with previously stated two methods. The strength of actuation capabilities in the direction longitudinal to the fiber shows significant improvements in the results obtained with the strain energy approach compared with those of the other two micromechanics methods.

Phenolic resin novolac matrix composites encapsulating processed construction and demolition waste micropowder of different grain sizings were manufactured using the appropriate molding techniques and were then studied. Characterizations by means of scanning electron microscopy, as well as elemental analysis by way of energy-dispersive X-ray analysis, were carried out. Additionally, the mechanical and thermal insulating behaviors of these materials were examined through bending and shear strength tests, in accordance with the three-point method and by determination of the thermal conductivity coefficient λ, respectively.

Metal-on-polyethylene (MoP) hip replacements with a CoCrMo alloy femoral head and an ultrahigh-molecular-weight polyethylene (UHMWPE) acetabular cup are strongly preferred due to their high clinical success. Despite this success, the wear of the bearing surfaces that causes a reduction in the prosthetic use of joint prostheses is still a baffling problem that cannot be solved. Although much research has been done on the tribological behavior of UHMWPE, there are a limited number of studies on the UHMWPE wear mechanism of all components in a hip prosthesis. This study aimed to determine the effect of all components of a total hip prosthesis on the wear behavior of UHMWPE according to three different gait cycles. The wear tests performed at the hip simulator were performed with reference to the hip joint movements and a maximum of 3000 N loads specified in ISO 14242-1. In addition to the abrasive and fatigue wear types of UHMWPE undercoat cups. It was observed that the third-body wear type, which was buried on the surface of polyethylene bearing Ti6Al4V alloy, occurred after 5 million cycles. As a result, according to wear test based on friction elements, it was determined that all hip prosthetic components play an active role in polyethylene wear due to repetitive movement and loading. Moreover, it was concluded that the wear model presented by finite-element analysis can predict the formation of wear in hip prostheses in a reasonable manner.

Unbleached cellulose obtained from corncobs was used to synthesize cellulose nanocrystals (CNCs). Corncobs are an agro-industrial residue that has a high cellulose content and can be used as a raw material to obtain CNCs. The cellulose was extracted from the corncobs by means of delignification in two stages. The first stage consisted of a pulping process with ethanol and acetic acid (organosolv method), and in the second stage, the corncob was treated with an organosolv method and potassium hydroxide, followed by sodium hydroxide and boric acid (extraction and purification) to eliminate hemicellulose. The obtained cellulose was not bleached, in order to maintain the groups corresponding to lignin and hemicellulose on their surface. Afterward, the obtained cellulose underwent acid hydrolysis to obtain CNCs, using sulfuric acid at 64%. These nanocrystals were characterized by X-ray diffraction, atomic force microscopy, thermogravimetric analysis and zeta potential. The CNCs obtained from the two types of unbleached cellulose showed lengths from 125.18 to 225.86 nm and diameters from 11.61 to 35.92 nm. The results indicate not only that CNCs can be obtained from unbleached cellulose corncobs but also that their characteristics are similar to those of CNCs obtained by means of bleached cellulose.