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Colored dyes are major sources of environmental pollution. Mineralization using heterogeneous catalysts is the method to remove such environmental pollutants. Herein, a green approach is used to prepare the nanocomposites, in which pulsed laser ablation of liquid (PLAL) is used. The synthesis of a ternary nanocomposite of ZnO/CuO/Al2O3 as a photocatalyst to degrade methylene blue (MB) dye is performed in an optimized ratio of 3:1:1 at pH = 10.37. To evaluate the structural, morphological, and optical features of the synthesized ternary nanocomposite, XRD, Raman spectroscopy, scanning electron microscopy (SEM), EDS, atomic force microscope (AFM), and UV–vis spectroscopy are used. The XRD pattern confirms that the ternary nanocomposite is highly crystalline in nature. The Raman spectra confirm the formation of the ternary ZnO/CuO/Al2O3 heterostructures. The AFM images of the ratio 3:1:1 show less agglomeration than the 1:3:1 and 1:1:3 ratios. The SEM images show agglomerated spheroids with rice-like morphologies and a mean particle size of around 40 nm. The energy bandgap (Eg) values lie in the UV region at 5.05, which means that the photocatalyst has enhanced its photocatalytic activity under sunlight. The degradation efficiency of 3:1:1 at pH = 10.37 achieves the highest value of 98.55% with a rate constant of 0.2265 min−1 after 15 min of illumination. [ABSTRACT FROM AUTHOR]

Introduction: Green synthesis of nanoparticle is considered as a promising method to synthesize a functionalized nanoparticle (NP) with no byproducts formed during the synthesis process when compared to chemical methods preparation. Compared to other traditional cancer treatment strategies, such as surgery, chemotherapy and radiotherapy, nanoparticle produced by green methods is considered as a powerful replacement to the above-mentioned treatment methods with no side effects. Aim: To determine the potential impact of GO/CeO2 nanoparticles NPs as an anti-tumor agent in biomedical field, an in vitro study. Methods: In the current study, CeO2 was synthesized using coprecipitation method. The method of preparation used is considered green due the usage of Allium Sativum extract in the synthesis of CeO2 nanoparticles. Graphene -Oxide (GO) was prepared by pulsed laser ablation in water (PLAL) which is also considered as a green method. The decoration of CeO2 on GO was achieved by mixing the GO with CeO2 nanocolloid. The as-prepared GO-CeO2 NPs was characterized using XRD, UV-visible spectrophotometer, FESEM, EDS and FTIR. For the in vitro study, nine CeO2 concentrations were used (starting from 0.98 – 250 µg/ml) as duplicate dilutions, to investigate the potential effect of CeO2 nanoparticles. The as-prepared GO/CeO2 were investigated against panel of cancer cell lines (human breast cancer cell line AMJ13, brain cancer cell line AMGM5, human oesophagus cancer cell line SK-GT-4) and compared with normal cell line REF both with/without using CeO2 in culturing. Results: The FESEM results show that the CeO2 NPs are homogeneous and nearly spherical in its shape with an average dimension of 55 nm. The FTIR analysis has proved that the as prepared CeO2 NPs are functionalized by the Allium Sativum extract. The in vitro results showed that the GO/CeO2 had significant potential impact in the high concentration 250 µg/ml at p> 0.05 against breast cancer cell line AMJ13 (with growth inhibition 51.04%) compared with other cell lines that showed less significant effect at p> 0.05 on brain cancer cell line AMGM5 (with growth inhibition 37.12%) and increased the proliferation rate on oesophagus cancer cell line SK-GT-4 and with no effects on control cell line REF during 48h of time exposure. Conclusions: According to the above results, we concluded that the as prepared CeO2 is a promising anticancer agent against breast cancer cell line that was proved to be safe on normal cell line REF. [ABSTRACT FROM AUTHOR]

Influence of laser treatment on mechanical properties, wear resistance, and Vickers hardness of aluminum alloy was studied. The specimens were treated by using Nd:YaG laser of energy 780 mj, wavelength 512 nm, and duration time 8 ns. The wear behavior of the specimens was studied for all specimens before and after treatment by Nd:YaG laser and the dry wear experiments were carried out by sing pinon-disc technique. The specimens were machined as a disk with diameter of 25 mm and circular groove in depth of 3 mm. All specimens were conducted by scanning electron microscopy (SEM), energy-dispersive X-ray fluorescence analysis (EDS), optical microscopy, and Vickers hardness. The results showed that the dry wear rate was decreased after laser hardening and increased Vickers hardness values by ratio of 2.4:1. The results showed that the values of wear rate for samples having circular grooves are less than samples without grooves after laser treatment.