This study's main idea is to explore the interaction between acrylic bone cement and bone tissue in total hip arthroplasty procedures. Acrylic bone cement has been widely used in total hip arthroplasty procedures over the years. The importance of the interaction between cement and bone tissue, as well as the penetration of cement into bone, has been the subject of extensive research. Analyses using SEM and EDAX have examined these aspects in detail, highlighting the importance of uniform cement distribution in strengthening and protecting the implant. Additionally, possible anomalies, such as the formation of voids or fissures in the cement, which can affect the long-term strength and stability of the implant, have been identified. These research findings have made significant contributions to understanding the need for a rigorous cement application technique to avoid such problems and ensure the success of the intervention. Furthermore, a detailed investigation revealed a specific case where acrylic bone cement was applied in an excessively thick layer, leading to significant penetration into the bone tissue. The lack of uniformity and reduced viscosity of the cement exacerbated this issue, emphasizing the need for careful cement application to ensure the stability and durability of the implant.

The purpose of teeth whitening is the removal of intrinsic or extrinsic discoloration via mechanical or chemical techniques that restore the teeth to their natural shade or lighten it, depending on the chosen method. Both the abrasive particles used in mechanical procedures and the oxidant agents applied in chemical bleaching are effective if they are used according to the stain aetiology, however, the risks associated with these products (e.g. potential tooth wear, sensitivity, damage of the enamel or dentin organic matrix) are not negligible. As a response to these issues, current research in the tooth whitening field is directed towards the development of safer whitening products such as dentifrices with lower abrasive index, natural bleaching agents, or laser-assisted whitening procedures that require shorter exposure time for optimal results. This review aims to provide a description of the currently available teeth whitening techniques and their limitations, as well as the novel alternatives that promise similar or superior results with less potential side effects. For a better understanding of the subject, the structure of the tooth, the causes of teeth discoloration as well as the mechanisms of action and chemistry behind the abrasive agents and peroxide-based whitening processes were also discussed.

Surface modification of steel is a crucial process in various industries, including automotive, construction, and aerospace . This process involves altering the outer layer of steel to enhance its properties such as corrosion resistance, wear resistance, and hardness. Different methods of surface modification can be employed, such as electrochemical processes, materials processing advancements, and the creation of special physical and chemical properties. This review paper provides a comprehensive analysis of surface modification techniques for steel, focusing on diffusion methods (nitriding, boronizing, and carburizing) and laser treatments (laser surface hardening, laser surface melting, and laser cladding). These methods enhance the microstructure and mechanical properties of steel components, offering improved surface hardness, wear resistance, and fatigue strength. Diffusion techniques alter the surface layer through the introduction of specific elements, creating hard, wear-resistant cases. Laser treatments provide precise, localized modifications with minimal distortion and a variety of coating possibilities. The review explores the process procedure, advantages, and limitations of each method, as well as their influence on the microstructure and mechanical processes. By evaluating these techniques, this paper aims to guide the selection of appropriate surface modification methods for optimizing steel performance and extending the lifespan of components in demanding environments.

Service structures could be built from different materials and concrete is commonly used in construction due to its beneficial mechanical properties, such as its superior compressive strength, long-lasting durability, and ability to resist fire. Structures are anticipated to withstand the various loads they encounter during their operational lifespan, which can typically be determined based on factors such as the type of service, geographical location, and dimensions. These loads can be accurately modeled using advanced software tools that are continuously evolving. However, fire incidents are difficult to predict, making it challenging to foresee their location, timing, and the extent of their impact on structures, resulting reductions in strength and unexpected stress. Therefore, in this study, to examine the performance of concrete of different strength grades and reinforced concrete (RC) beam specimens exposed to fire at different temperatures, an experimental investigation was carried out. During the test, the maximum duration of fire exposure taken is four hours and maximum concrete surface temperature considered is limited to 246°C. For the RC beams, test was conducted under one-point loading with different specimens of 25 mm and 35 mm concrete covers. The results showed that, the strength of RC beam after fire exposure reduces up to 18% and the compression strength of concrete at 246°C of fire exposure temperature with 25 MPa and 30 MPa were observed to drop by 32%, and 48%, respectively as compared to initial strength. Moreover, comparison of experimental results with numerical models were made. The results revealed that the predicted values of the residual compressive strength proposed by Hertz's model are in good agreement with the experimental values.

The research project’s primary goals were to develop occupational risk management protocols for people who perform maintenance tasks on electrical installations and, in turn, to develop new work tools designed to protect workers in those installations. The research project’s findings are presented in this paper. In order to check the behaviour of the safety characteristics of the protective equipment material under certain influence of professional risk factors, protective equipment materials were subject to tests. The components of in use or new electro-insulating equipment, were evaluated through sampling. Electro-insulating materials underwent dielectric, mechanical, attrition testing, and chemical agent application. The findings revealed the weakness of some electrical insulating materials whose declared duration of use exceeded five years after commissioning, necessitating the assessment of new technical standards for health and safety workplace.

This study demonstrated that high-purity alumina can be generated from kaolin using various methods. It examined different leaching techniques, considering the size and percentage recovery of alumina by weight in selected kaolin samples, the calcination temperature, and the molar concentration of acids over time. Additionally, it analyzed the characteristics of several kaolin sources in Nigeria with the aim of extracting alumina. The research indicates that Nigerian kaolinite clay typically contains 22–40% alumina by weight. However, leaching kaolin yielded alumina with a purity of 60–97 wt%, with particle sizes ranging from 16 to 177 nm. Alumina derived from kaolin is deemed beneficial for manufacturing refractory materials, water purification, and biomedical applications.

The article presents a circular economy proposal as a way to promote greater sustainability in the footwear industry. As part of the work, we analysed the essential components for a shoe and the materials used in the production of footwear. Currently, new proposals have emerged for footwear that use materials derived from waste and the forwarding of specific end-of-life products. These new concepts are associated with added value and targeted marketing towards sectors of society more concerned with the industry's environmental impact. This reinforces the interest in the positioning of the footwear industry in relation to the circular economy. The purpose of this article focuses on the last phase of the circular economy – recycling, educating, and valuing the role of the consumer through the collection, treatment and forwarding of used footwear materials with the aim of reducing waste in landfills but simultaneously increasing awareness of the footwear industry.

In this research, rice husk ash (RHA) and eggshell ash (EGA) were used as biogenic materials for total replacement of pure quartz (SiO2) and calcium oxide (CaO) respectively in the traditional 45S5 bioactive glass composition by powder metallurgy route. Body formulation with nominal composition 45% RHA (SiO2), 24.5 EGA (CaO), 24.5% Na2O and 6% P2O5 was composed. The batch material was properly mixed with addition of 2% PVA (Polyvinyl alcohol) as binder and compacted at 70 MPa to produce compact samples of 40 x 20 mm. The samples were then allowed to dry in an ambient temperature followed by sintering at 1000°C for 2 h, then allowed to cool to room temperature. Selected samples were immersed inside prepared simulated body fluid (SBF – pH 7.4) at 37 °C for 5, 9, and 18h respectively. Physical, microstructure and phase evaluation were conducted to examine the developed bio-ceramic. The results showed the bio-waste based 45S5 bioceramic has bulk density and porosity of 1.02 g/cm3 and 62% respectively while deposits of carbonate-hydroxyapatite were found to increase with immersion period showing good bioactivity and affirm that the developed bio-waste based bioceramics are bioactive and can find suitable application bone repair.