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Fiber-metal laminates (FMLs) are rapidly advancing materials that combine the characteristics of resin-based composites and metals. These properties can be further enhanced by incorporating nanoscale particles, resulting in a variant known as FMLs-Nano. This study explores the mechanical properties of FMLs with the incorporation of Graphene Oxide (GO) and investigates for the first time the influence of GO on bonding strength, aiming to improve the laminate's performance during the forming operation by eliminating delamination defects. The goal is to expand the potential applications of FMLs-Nano and enable the production of intricate components. To evaluate the influence of GO, we conducted tests on several mechanical aspects, including tensile strength, flexural performance, and lap shear strength. These tests involved using different GO fractions in the laminate. Microscopy was employed to examine damage patterns and understand failure behavior. Additionally, deep drawing experiments were performed and compared with conventional FMLs to evaluate the GO influence on delamination failure. The results indicate that FML-GO exhibits superior tensile performance compared to conventional FMLs, with FML-GO tensile strength and Young's modulus improved by 11.7% and 13.5%, respectively. Moreover, flexural and interface shear strength showed remarkable improvements, with an increase of 134% and 150% compared to conventional FMLs. These improvements were verified through mechanical testing and further confirmed by scanning electron microscope observations. Additionally, deep drawing experiments demonstrated significant improvement as delamination of the FML layers was successfully eliminated during the forming process. [ABSTRACT FROM AUTHOR]

Ferrisilicate was considered a crystalline zeolite containing iron (III) and silicon in the zeolite lattice positions. The aim of this work is to study the influence of Fe2O3/SiO2 molar ratios contained in the Fe-silica on the properties of geopolymer materials derived from waste fired clay brick and metakaolin. Fe-silica with various Fe2O3/SiO2 molar ratios of 0.2, 0.4, 0.6, 0.8 and 1.0 were synthesised using rice husk ash and hematite. 0 and 10 wt. % of each type of aluminosilicate is added to each type of Fe-silica. A commercial sodium silicate solution with a SiO2/Na2O molar ratio of 1.6 is used as a hardener. X-ray diffractometry and Fourier Transform Infrared spectroscopy are used for the characterisation of the Fe-silica and the geopolymers. In addition to these analyses, the compressive strengths of the geopolymer materials have been measured and the fragments obtained have been examined using a scanning electron microscope. The results show that the compressive strengths of metakaolin-based geopolymers increase from 53.34 to 69.08 MPa when the Fe2O3/SiO2 molar ratios contained in the Fe-silica are incremented from 0 to 0.8. When the Fe2O3/SiO2 molar ratio is increased from 0.8 to 1.0, they are reduced from 69.08 to 63.22 MPa. In contrast, those of geopolymer materials derived from waste fired clay brick decrease from 45.42 to 21.15 MPa when their Fe2O3/SiO2 molar ratios rise from 0 to 0.6 increases from 21.15 to 24.11 MPa beyond 0.6. The micrograph of the geopolymer material from the mixture of metakaolin and Fe-silica with a molar ratio of Fe2O3/SiO2 equal to 0.8 is more compact, homogeneous and partially smooth compared to other geopolymers. The presence of hematite and cristobalite, which act as fillers, is evident from the X-ray patterns of geopolymer materials after the addition of Fe-silica. This work shows that the addition of metakaolin to multi-molar of Fe-silica significantly improves the compressive strength of geopolymer materials. On the other hand, this addition leads to a reduction in the compressive strength when waste fired clay brick is used. [ABSTRACT FROM AUTHOR]

Recently, thermoelectric (TE) materials have seized great attention for their role in clean energy conversion applications. Cu2S are p-type super-ionic conductors featuring a narrow band gap of 1.7 eV while exhibiting outstanding thermoelectric characteristics. The Cu2S matrix and the CuO nanoinclusions were successfully synthesized via solvothermal and hydrothermal routes, respectively. The morphological observations made through scanning and transmission electron microscope ensured the homogeneous distribution of CuO nanoinclusions in the Cu2S matrix, hence, the formation of standard Cu2S/CuO composites. In this work, we have introduced a "combined strategy" to boost the figure of merit (zT). The Seebeck coefficient reached the maximum of 271.86 μVK−1 at 573 K for the 20 wt% CuO sample (a 71.45% gain when compared to the pure Cu2S) owing to the filtration of low-energy carriers at the CuO potential barriers (2.5 eV). The Cu2S/20 wt% CuO sample achieved the minimum thermal conductivity values. At 573 K, We recorded a vast power factor value of 952.66 μWm−1 K−2 (32.23% gain) for the Cu2S/15 wt% CuO sample. These values are vastly higher than previously reported for the copper sulfides-based TE materials. Consequently, an optimised zT value of 0.44 (214.29% gain) was accomplished for the Cu2S/15 wt% CuO sample at 573 K. The strategy presented in our study can also be extended to other TE materials, especially for the promising copper chalcogenides to improve their zT values. [ABSTRACT FROM AUTHOR]

In this study, aqueous Cystoseira crinite extract was used to successfully biosynthesize ZnO and C-doped ZnO samples. X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray (EDX), FTIR, and UV–vis techniques were used to characterize the biosynthesized samples. XRD technique confirmed the crystalline structure of ZnO and C-doped ZnO. EDX confirmed the formation of C-doped ZnO. SEM analysis revealed the spherical shape of the samples with agglomeration. FTIR spectra showed that phenolic compounds and protein molecules are present in the Cystoseira crinite extract. The photocatalytic activity of the prepared photocatalysts was investigated using crystal violet (CV) as a model of the cationic dyes and methyl orange (MO) as a model of the anionic dyes. 5%C-doped ZnO calcined at 500 °C showed an optimum photocatalytic efficiency of 92.7% and 87.8% for CV and MO dyes, respectively. The improved photocatalytic activity could be attributed to the narrower optical band gap of C doped ZnO than pure ZnO. The photocatalytic activity of CV and MO dyes follows the first-order kinetics with high correlation coefficient values. [ABSTRACT FROM AUTHOR]

The main goal of this work is to study the effects of some transition metal-oxides, i.e. ZnO, TiO2, and Fe2O3, on inhibition of spinel formation during cordierite fabrication from granite waste, talc, and alumina by direct coagulation casting method. Moreover, the effect of these oxides on sinterability, microstructure, hardness and electrical properties was achieved. The casted specimens were sintered at different temperatures then examined by X-ray diffraction technique to follow the formed phases. The physical properties were determined according to Archimedes rule. The microstructure was also investigated by scanning electron microscope, while the hardness was determined by Vicker's method. The electrical properties were evaluated by an impedance analyzer. The results indicated that sintered cordierite-spinel ceramics were successfully prepared with inhibition of spinel formation after addition of some transition metals and sintering up to 1250 °C. ZnO promoted the formation of spinel while TiO2 and Fe2O3 inhibited the formation of spinel and promoted the formation of cordierite. The ZnO-containing cordierites exhibited their best properties after sintering at 1200 °C, while the samples containing TiO2 and Fe2O3 showed their best properties after sintering at 1250 °C. The physical, mechanical and electrical properties were improved after increasing the amount of added metal oxides. The dielectric constant values were higher for the samples that contain TiO2 than those contain Fe2O3 and ZnO. Moreover, the hardness of all samples was in a narrow range of 6.14–6.61 GPa. [ABSTRACT FROM AUTHOR]

In this study, Chrysothemis pulchella leaf extracts were used to prepare gold nanoparticles (AuNPs) for anticancer and antimicrobial applications. The nanoparticles were characterized using UV-Visible spectroscopy, powder X-ray diffraction method, Scanning and transmission electron microscopic (SEM/TEM) techniques. The UV–vis spectroscopy revealed characteristic absorption band at 527 nm whereas X-ray diffraction analysis showed characteristic crystalline peaks typical of AuNPs and carbon peaks emanating from the plant extract. The energy dispersive X-ray spectroscopic (EDXS) studies showed the following elements: C, O, Na, Mg, Cl, K, Ca and Au. The microscopic analysis using Scanning and Transmission Electron Microscopes showed spherical nanoparticles with average size of 14.7 nm. Cytotoxic tests showed that the AuNPs were toxic to human embryonic kidney (HEK-293) and HELA cells at IC50 dosage of 34.5 and 54.05 µg respectively. The nanoparticles also proved to have broad spectrum antimicrobial properties as they inhibited the growth of some pathogenic micro-organisms. [ABSTRACT FROM AUTHOR]

The synthesis of polymers using environmentally friendly materials is on the rise. New chitosan, oxidized pectin, and tantalum metal–organic framework hydrogel were synthesized using chitosan and pectin, which are both available and environmentally friendly polymer materials. By scanning electron microscope images, energy-dispersive X-ray spectroscopy and EDAX mapping, X-ray diffraction pattern, Fourier transform infrared spectrum, and N2 adsorption/desorption isotherm curve, the structure of the synthesized polymer was confirmed. A specific surface area of about 26 m2/g was observed from the final system. The same morphology, and 51 nm particle size were other features of synthetic chitosan, oxidized pectin, and tantalum metal–organic framework hydrogel. The antimicrobial activity of the synthesized polymer was studied on Yersinia ruckeri, Vibrio fluvialis, Edwardsiella tarda, Lactococcus garvieae, and Streptococcus iniae as microbial agents of aquatic pathogens. The synthetic polymer studied in this research can be reported as a robust antimicrobial compound with an MBC of 4–128 mg/ml. A key aspect of this study is the synthesis of new polymers using environmentally friendly and controllable methods. Among other novelties of this study, it can be mentioned that it is effective against common pathogenic strains of humans and aquatic, which in some cases was more effective than available commercial drugs. [ABSTRACT FROM AUTHOR]

This work aims to develop a bioactive ceramic substance to be used as a graft during maxillary sinus augmentation. Cordierite was created by sintering at 1400 °C a combination of 51.4% silica, 34.8% alumina, and 13.8% magnesia. X-ray Diffraction (XRD) was used to identify the manufactured chemical, and patterns revealed that indialite was identified as the predominate phase. Prepared cordierite had been mixed with hydroxyapatite to form three batches of cordierite:hydroxyapatite (Cor:HA). They were (50:50), (40:60), and (30:70), representing the first, second, and third batch respectively. Then, each batch had been sintered at 700, 900, and 1100 °C to get a new ceramic material. XRD analysis for the sintered samples indicates the presence of whitlockite phase in addition to HA and cordierite. To investigate the microstructure of manufactured samples, scanning electron microscope (SEM) was used. After 21 days of soaking to estimate degradability, data reveal that degradation rate substantially increased with increasing soaking period. The sample comprising 30:70 of (Cor:HA) and sintered at 1100 °C (Z7) employing the greatest degradability of around 34.53% after three weeks. The bioactivity outcomes showed that all grafts were bioactive, as indicated by the detection of apatite spheres using a Field Emission Scanning Electron Microscope. Also, apatite formation was confirmed via Energy Dispersive X-ray (EDX) shows appearance of Ca, P, O, and H peaks. Also, antibacterial and histological analysis were performed. As a result, Z7 grafting powder shows unique in vivo and in vitro behavior, in term of bioactivity, bacterial activity and bone formation. [ABSTRACT FROM AUTHOR]