The incorporation of fiber reinforcements into polymer matrices has emerged as an effective strategy to enhance the mechanical properties of composites. This study investigated the tensile and fracture behavior of 3D-printed polylactic acid (PLA) composites reinforced with chopped carbon fibers (CCFs) through experimental characterization and finite element analysis (FEA). Composite samples with varying CCF orientations (0°, 0°/90°, +45°/−45°, and 0°/+45°/−45°/90°) were fabricated via fused filament fabrication (FFF) and subjected to tensile and single-edge notched bend (SENB) tests. The experimental results revealed a significant improvement in tensile strength, elastic modulus, and fracture toughness compared to unreinforced PLA. The 0°/+45°/90° orientation exhibited a 3.6% increase in tensile strength, while the +45°/−45° orientation displayed a 29.9% enhancement in elastic modulus and a 29.9% improvement in fracture toughness (259.12 MPa) relative to neat PLA (199.34 MPa√m). An inverse correlation between tensile strength and fracture toughness was observed, attributed to mechanisms such as crack deflection, fiber bridging, and fiber pull-out facilitated by multi-directional fiber orientations. FEA simulations incorporating a transversely isotropic material model and the J-integral approach were conducted using Abaqus, accurately predicting fracture toughness trends with a maximum discrepancy of 8% compared to experimental data. Fractographic analysis elucidated the strengthening mechanisms, highlighting the potential of tailoring CCF orientation to optimize mechanical performance for structural applications.

Carbon nanotubes (CNTs), a type of carbonaceous material, have extremely distinctive qualities in terms of tensile strength, heat stability, electrical conductivity, catalysis, and adsorption. These properties rely on structure, length, and thickness. Carbon nanotube and metal oxide combination have been successfully used over the past few decades to create carbon nanomaterials with extraordinary features. The current study offers an outline of the developments in the theory, procedures, and chemical modification of CNT with metals or polymers. This review presents different synthesis methods of functionalized CNTs along with their properties and factors affecting their adsorption capacity. In addition, it explains the role of different functionalized CNTs in removing different metals like Pb ^2+ , Cd ^2+ , Cr ^3+ , Cr ^6+ , Ni ^2+ , Tl ^+3 , and Hg ^2+ from wastewater. The adsorption capacity of these modified CNTs is in the range of 130–180 mg g ^−1 . This review offers an essential understanding of the methods for creating multifunctional nano-hybrids for various applications and prospects of using nanomaterials for environmental remediation.

Here, we present a pathway for the green synthesis of Ag/AgCl nanoparticles derived from freshwater Chara vulgaris algae. The formation of Ag/AgCl NPs is confirmed by XRD, UV-Vis spectroscopy, and SEM techniques. The volume with an aqueous extract of Chara vulgaris: AgNO3 ratio 3:1 possessed optimal synthesised Ag/AgCl NPs. A plasmon absorbance peak, at 395 nm was observed in the UV-vis spectrum. XRD patterns confirmed the highly crystalline FCC structure of Ag/AgCl NPs. SEM imaging of Ag/AgCl NPs indicated nanoparticles of size 16.99 +/- 0.3 nm. The antibacterial activity of Ag/AgCl NPs was evaluated against Staphylococcus aureus, Escherichia cob, Klebsiella pneumonia, and Pseudomonas aeruginosa. Combining Ag/AgCl NPs with antibiotics causes growth inhibition of both Gram-positive and Gram-negative bacteria. The fractional inhibitory concentration index (FICI) is used to evaluate the synergistic antimicrobial effect of combining nanoparticles with antibiotics. The combinations of Ag/AgCl NPs with Gentamicin, Erythromycin and Vancomycin show a partial synergistic activity against E. cob, K. pneumoniae and P. aeruginosa, respectively. The combination of Ag/AgCl NPs with antibiotics could potentially prohibit the development of resistant bacteria against antibiotics.

Oxidative desulfurization process (ODS), enhanced with a novel metal oxide (Ag ions) as an active component over nano-zeolite that has not been reported in the literature, is used here to improve the fuel quality by removing mercaptan (as a model sulfur compound in the light naphtha). Nano-crystalline (nano-support (Nano-zeolite)) composite is prepared by Incipient Wetness Impregnation method loaded with a metal salt to obtain 0.5, 1 and 1.5% of Ag2O3 over Nano-zeolite. The new homemade nano-catalysts (Ag2O3/Nano-zeolite) prepared are characterized by Brunauer–Emmett–Teller (BET) (surface area, pore volume and pore size), X-ray Diffraction (XRD), Fourier Transform Infra Red (FTIR), and Scanning Electron Microscopy (SEM) analysis. The ODS process is then used to evaluate the performance of the catalysts for the removal of sulfur at different reaction temperatures (80–140 °C) and reaction times (30–50 min) in a batch reactor using the air as oxidant. 87.4% of sulfur removal has been achieved using 1% silver oxide loaded on Nano zeolite (1% of Ag2O3/Nano-zeolite) giving a clear indication that our newly designed catalyst is highly efficient catalyst in the removal of sulfur compound (mercaptan) from naphtha. A new mechanism of chemical reaction for sulfur removal by oxygen using the new homemade catalyst (Ag2O3/Nano-zeolite) prepared has been suggested in this study. The best kinetic model parameters of the relevant reactions are also estimated in this study using pseudo first order technique based on the experimental results. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Bimetallic Au –Pt catalysts supporting TiO2 were synthesised using two methods; sol immobilization and impregnation methods. The prepared catalyst underwent a thermal treatment process at 400◦ C, while the reduction reaction under the same condition was done and the obtained catalysts were identified with transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS). It has been found that the prepared catalysts have a dimension around 2.5 nm and the particles have uniform orders leading to high dispersion of platinum molecules .The prepared catalysts have been examined as efficient photocatalysts to degrade the Crystal violet dye under UV-light. The optimum values of Bimetallic Au –Pt catalysts supporting TiO2 have been found (0.05g of the catalyst prepared in sol immobilization method, 0.07 g of the synthesised in impregnation procedure. The impact of pH on the degradation reaction was tested; it has been found that pH 10 is the best media for the reaction. The effect of temperature has been discussed when various temperatures were used, and the heat of photoreaction Ea was estimated from the Arrhenius relationship, it has been concluded that the reaction is independent of temperature as the activation energy was very small (Ea= 22 kJ/ mole). The thermodynamic functions; entropy, enthalpy and the free energy have been figured out. It has been found that the positive values of enthalpy ∆H# refer to endothermic reaction, moreover, it has been demonstrated that the photoreaction is an endergonic one according to the calculated values of the free energy of activation. It has been noticed that when temperature increases, it promotes the production of free radicals, but it has been noticed that exceeding the temperature more than the used range causes reducing the percentage of degradation of crystal violet, the reason is due to the limitation conditions of adsorption process at higher temperature on the surface of the catalyst.

Development of composite materials has increased rapidly in different fields of sciences. This offers new structures of reinforcement materials and risen. More recently, the use of nanomaterials as reinforcement materials has proliferated. This research studies the mechanical properties and electrical characteristics of hybrid composite materials. Glass reinforced epoxy (GRE) was used as a basic composite in addition to the nanomaterial which was mixed with the risen using different percentages. Multi-wall carbon nanotubes (MWCNT) and Silica (Silicon Dioxide SiO2) were used as nano-particles. The ratios of nano-particles used to reinforce the Epoxy were (0.1, 0.2, and 0.5%) of weight ratio for MWCNT and (1, 2, and 5%) of weight ratio for Silica nanoparticles (SiO2). The results showed that the ultimate strength for GRE with 0.1 wt%MWCNT-1 wt%SiO2 was the highest, while Young’ modulus for GRE with 0.2 wt%MWCNT-2 wt%SiO2 was the highest. In addition, the samples with 0.1 wt%MWCNT-1 wt%SiO2 showed a magnificent value of electric conductivity. Having finished the mechanical tests, the fracture surfaces were comparatively examined using scanning electron microscopy (SEM).

PolyHIPEs (polymers synthesized within high internal phase emulsions) are porous materials with high specific surface area which suggests their use in ion exchange applications. We have successfully synthesized and functionalized such materials to make then hydrophilic by mixing an oil phase and an aqueous phase containing deionized water and sulphuric acid. The PolyHIPE samples were also subjected to a further microwave-assisted post-sulphonation process to increase hydrophilicity and water uptake. Post sulphonation results in a higher concentration of benzenesulphonic acid groups which are necessary for ion exchange. PolyHIPE beads processed in this manner were able to remove low concentrations (∼20mg/l) of nickel and copper ions from solution with high removal efficiency (80-95%) depending on the initial pH of the water. However, recovery of the metal through regeneration at different pH levels was less successful.