Nanotechnology applications have recently developed in the field of smart sensors that convert energy from one form to another. Nanotechnology is one important source to renewable energy applications, such as the use of solar energy to generate electrical energy A concentration of 0.2 w/v of poly methyl meta acrylic dissolved in dimethylformamide was prepared using hot plate magnetic stirrer magnetic with a temperature up to 50 ° C, and the mixing continued for an hour. 0.02 Percentage of magnesium oxide nanoparticles was added to (poly methyl methacrylate/dimethylformamide) solution and dispersed by ultrasonic dispersion device. The samples were cast into glass containers to obtain thin films with 0.02 mm diameter after drying for 24 hours. Infrared assays were conducted to study the interactions between the polymer and the nanoparticles via studying the nature of the bonds. The differential scanning calorimetry test was performed to measure the thermal properties of the samples. Atomic force microscopy was used to study the surface properties of the samples. The energy gap of samples was calculated. The results proved that the interaction between polymer and nanoparticles is physical interaction. The differential thermal calorimeter results also showed that the adding of MgO nanoparticles leads to increase the glass transition temperature by a small value from (80 °C) to (82 °C). On the other hand, the softening point decreases from (132 ° C) to (120 ° C) and melting point decreases from (173 ° C) to (135 ° C) after adding nanoparticles. As for the results of atomic force microscopy, it was proved that the surface roughness decreases from (2.08 nm) to (1.7 nm) after adding nanoparticles, while the bearing index increases from (0.369) to (0.582). Also, the results of the energy gap proved that the addition of nanoparticles leads to decrease in the energy gap from (4.3 – 4.1) eV, which leads to increase in electrical sensitivity.

Purpose: The purpose of this study is to evaluate the influence of natural sisal fibers on mechanical properties of polymethyl methacrylate (PMMA). Materials and Method: In total, 90 specimens are prepared to be used in the study. The specimens are divided into three main groups, 30 specimens of heat cure PMMA without additives (control) and experimental groups of 60 specimens of heat cure PMMA with salinized sisal fibers with two different weight percentages (5% and 10%) wt. Three point bending test is performed to evaluate the flexural strength of the specimens, while the impact strength is done by impact testing Charpy's machine and tensile test is performed according to ASTM D‐638. Analysis of variance (ANOVA) test is used for statistical analysis. Results: Impact test results indicate a highly significant in the reinforced specimens when compare with control specimens. Tensile strength significantly increases after reinforcement with fibers. Nonsignificant difference is detected in flexural strength among the reinforced groups and control group. Conclusion: Reinforcement of the heat cured acrylic resin with natural sisal fibers significantly increases its impact strength and tensile strength with nonsignificant in flexural strength.

Chitosan holds net ionic positive charges, which contribute its ability to chemically bind with negatively charged fats, lipids, metal ions, proteins, and microorganisms. Magnesium oxide (MgO) nanoparticles are important inorganic materials with a wide band-gap used in many applications such as catalysts, antibacterial and medical products. The aim of this study was to investigate the effect of Chitosan (CHT) hydrogel loaded MgO nanoparticles on the bacterial growth. CHT/ poly vinyl alcohol (PVA)/ poly ethylene glycol (PEG) hydrogel was blended with various amounts of MgO nanoparticles. The surface morphology of the obtained blends was investigated by Field Emission Scanning Electron Microscope (FE-SEM). Evidently, surfaces with appropriate roughness were obtained for most of the prepared hydrogels. Fourier Transform Infrared Spectroscopy (FT-IR) and Energy Dispersive X-Ray analysis (EDX) were also included in this paper. Thermal properties of all samples was studied by DSC-TGA curves. The antibacterial activity of the prepared hybrids CHT/PVA/PEG/MgO nanoparticles have performed against gram positive bacteria Staphylococcus aureus (S.aureus) and Streptococcus, as well as gram negative bacteria Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E.coli). In this study, MgO nanoparticles various proportions presented high efficiency towards gram positive microorganisms. High resistance of gram negative bacteria against the final products was extremely detected according to measured inhibition zones which were between (0-9) mm.

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