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This study presents a pioneering methodology for the synthesis of aluminum matrix composites (AMCs) fortified with biochar, sourced from renewable biomass feedstocks. Employing a systematic approach, various biochar weight percentages were meticulously investigated to discern their impact on the mechanical and tribological properties of the resulting composites. Through a comprehensive battery of tests, encompassing evaluations of compressive strength and hardness, the study elucidated significant enhancements in mechanical robustness consequent to biochar integration. Notably, the mixture formulation with 7.5 wt. % biochar emerged as the optimal configuration, showcasing an impressive 8.83% augmentation in compressive strength and a notable 15% elevation in the hardness relative to the pristine aluminum pure matrix. The research extends beyond traditional analyses, introducing an exploration of tribological performance. The incorporation of biochar is anticipated to impart solid lubricating properties, influencing wear and friction characteristics. Future research directions may delve into the nuanced interplay between biochar content and tribological enhancements, offering insights into the tailored manipulation of mechanical and tribological properties in AMC through biochar reinforcement. The examination of wear and friction exhibited that the friction coefficient decreased by 6.4% when 10 wt. % of biochar was added. Furthermore, the wear resistance improved proportionally with the biochar weight percentage, regardless of the normal loads applied. The finite element model further demonstrated an enhancement in load-carrying capacity due to biochar incorporation. Finally, analysis of the texture of the rubbed surface presented that the inclusion of biochar in an AL matrix changed the way wear occurs and decreased the amount of weight lost during friction. The resulting materials not only exhibit improved mechanical strength but also hold promise for applications in industries that demand robust, environmentally conscious solutions with enhanced tribological performance. [ABSTRACT FROM AUTHOR]

Ankle and foot orthotics are suggested for gait rehabilitation therapy after a stroke. Clinical practice necessitates adjusting the ankle foot orthosis torque to accommodate each patient's unique stride and body function. The objective of this paper is to develop a customized, cost-effective footplate orthosis from carbon fibers, manufactured using 3D printing, for individuals with partial foot amputations. The footplate is designed for use in developing nations and aimed to be made available with a reduced lead time. The experiment work carried out in this research is used to design, analyze, and validate a prosthetic footplate. A foot of size UK 7 with a 2 mm thick model of the human foot was modeled using Unigraphics-NX. The footplate's design is being tested both conceptually and empirically. The footplate manufactured by applying load at toe and heel shows that the carbon fiber successfully restores leg length and reduces pressure on the feet's delicate distal end. [ABSTRACT FROM AUTHOR]

This study investigates the enhancement of mechanical and tribological behavior in polymethyl methacrylate (PMMA) composites reinforced with graphene oxide (GO) as a solid lubricant filler for advanced biomedical applications, particularly dental implants. PMMA/GO composites were prepared with varying weight percentages of GO (0, 0.2, 0.5, 0.7, and 1 wt. %) to assess their impact on material performance. A noteworthy improvement in both tensile strength and Young's modulus was detected, reaching up to 141% and 10.6%, respectively, at optimized GO loadings of 1%. Microstructural analysis utilizing scanning electron microscopy for the worn surface revealed enhanced dispersion and interfacial adhesion between GO and the PMMA matrix, reinforcing mechanical coherence. Tribological properties also demonstrated enhancement, with PMMA composites containing 1 wt. % GO exhibiting optimal mechanical and tribological characteristics compared to lower weight fractions. Moreover, microscopic examination revealed a shift in the wear mechanism of the PMMA-GO composite, which was attributed to the lower friction coefficient obtained by GO integration. [ABSTRACT FROM AUTHOR]

This research work highlights the tribomechanical investigations of using a low loading fraction of two ceramics combinations, Alumina (Al2O3) and Silicon Carbide (SiC) as reinforcement for Low-density Polyethylene (LDPE) matrix. The hybrid additives with different weight percentages (0.1 + 0.1, 0.25 + 0.25 and 0.5 + 0.5 wt%) were mixed with LDPE matrix and the degree of homogeneity was controlled using double-screw extruder prior to fabricating the composite samples via the injection molding machine. The nanoparticles fillers were characterized by field emission scanning electron microscope (FESEM), EDX and particle size analyzer to check its morphology, composition and size distribution. Thermogravimetric analyzer (TGA) and melting flow index (MFI) were performed for the fabricated nanocomposites samples. The mechanical properties of the nanocomposite were evaluated by performing tensile test, bending test and Shore-D hardness test, while the tribological performance was investigated using a ball on desk apparatus under different applied loads and sliding times. Moreover, in order to confirm the load-carrying capability of the composite, contact stresses was measured via finite element model using ANSYS software. The results show that the incorporation of low fraction hybrid ceramic nanoparticles can contributed positively in the tribological and mechanical properties. Based on the experimental results, the maximum improvement in the tensile strength was 5.38%, and 8.15% for hardness LDPE with 0.5 Al2O3 and 0.5 SiC, while the lowest coefficient of friction was noticed under normal load of 10 N, which was approximately 12.5% for the same composition. The novel approach of incorporating low fraction hybrid ceramic nanoparticles as reinforcement for LDPE matrix is investigated, highlighting their positive contributions to the tribological and mechanical properties of the resulting nanocomposites. [ABSTRACT FROM AUTHOR]

The efficient utilization of rice waste has the potential to significantly contribute to environmental sustainability by minimizing the waste impact on the environment. Through repurposing such waste, novel materials can be developed for various biomedical applications. This approach not only mitigates waste, but it also promotes the adoption of sustainable materials within the industry. In this research, rice-straw-derived nanofibers (RSNFs) were utilized as a reinforcement material for high-density polyethylene (HDPE). The rice-straw-derived nanofibers were incorporated at different concentrations (1, 2, 3, and 4 wt.%) into the HDPE. The composites were fabricated using twin-screw extrusion (to ensure homogenous distribution) and the injection-molding process (to crease the test samples). Then, the mechanical strengths and frictional performances of the bio-composites were assessed. Different characterization techniques were utilized to investigate the morphology of the RSNFs. Thermal analyses (TGA/DTG/DSC), the contact angle, and XRD were utilized to study the performances of the HDPE/RSNF composites. The study findings demonstrated that the addition of RSNFs as a reinforcement to the HDPE improved the hydrophilicity, strength, hardness, and wear resistance of the proposed bio-composites. [ABSTRACT FROM AUTHOR]

Aluminum composites are preferred in many kinds of applications such as aviation, space, automotive, and marine, owing to their outstanding properties, high strength, and corrosion resistance. The main objective of the current study is to evaluate the mechanical properties of aluminum alloy 6061/titanium dioxide (micro-TiO2) microcomposite synthesized using the stir casting method. The effects of changes in stir casting parameters, such as stirring speed and tiring durations, were studied. Al6061 matrix was reinforced with micro-TiO2 particles with weight fractions of 1, 2, 3, 4, and 5 wt.%. Microstructural and chemical analyses were conducted to explore microstructural transformation resulting from the presence of the TiO2 microparticles. The mechanical characteristics were evaluated, and the results showed a considerable enhancement in the mechanical strength and hardness resulting from the incorporation of micro-TiO2 into Al606. The additions of 2 wt.% and 5 wt.% of micro-TiO2 recorded the highest ultimate tensile strength and hardness, respectively. [ABSTRACT FROM AUTHOR]

Background: Primary gastric lymphoma (PGL) is the commonest form of extranodal lymphomas of the gastrointestinal tract. The majority are B-cell non-Hodgkin lymphomas. The most common type is diffuse large B-cell lymphoma (DLBCL) followed by marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT). The aim of this study is to determine the prevalence, classification and pathological pattern of primary gastric lymphoma in comparison with other gastric malignancies and to compare the results with that observed worldwide. Methods: A retrospective cohort study of PGL diagnosed at King Abdulaziz Medical City, National Guard Health Affairs, Riyadh, Saudi Arabia between the years 2013 and 2018. Data will be presented as mean + standard deviation for continuous variables, and frequencies (percentages) for categorical variables. Results: PGL represents 30% of all gastric malignancies with mean age of 64.2 years and slight male predominance. DLBCL is the commonest type (72.2%) followed by MALT lymphoma (14%), anaplastic large cell lymphoma (5%), peripheral T-cell lymphoma, NOS (3%), mantle cell lymphoma (3%) and plasmacytoma/myeloma (3%). 86.7% show association with gastritis, however, H. pylori is observed in 23.5% of PGL with majority being with DLBCL and only 1 case of MALT lymphoma. Conclusion: PGL is the second commonest malignancy of the stomach where most of the cases are DLBCL followed by MALT lymphoma. There is no difference observed in relation to age and sex compared with those observed in the literature. Further analysis is recommended to evaluate the association with H. pylori in our population. [ABSTRACT FROM AUTHOR]

Carbon-based perovskite solar cells (PSCs) have emerged as a hopeful alternative in the realm of photovoltaics. They are considered promising due to their affordability, remarkable durability in humid environments, and impressive electrical conductivity. One approach to address the cost issue is to use affordable counter electrodes in PSCs that do not require organic hole transport materials (HTMs). This study utilized an innovative and economical method to create NiO x /PANI nanocomposites. Later, these nanoparticles were integrated into a carbon paste to act as an HTM. This incorporation is intended to optimize charge extraction, improve interfacial contact, align energy levels, reduce energy loss, minimize charge recombination, and protect the perovskite (FAPbI 3 ) surface from degradation. The optoelectronic properties of these devices were investigated, and all cells showed improved efficiency compared to control cells. The NiO x /PANI doped carbon (NiO x /PANI+CE) exhibited excellent performance due to strong hole conductivity, well-aligned energy levels, and the formation of stepwise band alignment at the perovskite interface., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)