This study aimed to evaluate the radiological hazards of uranium (238U), thorium (232Th), and potassium (40K) in microgranitic rocks from the southeastern part of Wadi Baroud, a northeastern desert of Egypt. The activity concentrations of the measured radionuclides were determined by using a gamma-ray spectrometer (NaI-Tl-activated detector). The mean (238U), (232Th), and (40K) concentrations in the studied rocks were found to be 3680.3, 3635.2, and 822.76 Bq/kg, respectively. The contents in these rocks were elevated, reaching up to 6.3 wt%. This indicated the alkaline nature of these rocks. The high ratios of Th/U in the mineralized rocks could be related to late magmatic mineralization, suggesting the ascent of late magmatic fluids through weak planes such as faults and the contact of these rocks with older granites. The present data were higher than those of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) guideline limits. All the radiological hazard results indicated high human health risks. This confirmed that this area is not radiologically safe, and care must be taken when working in this area. This study showed that the area under investigation had high U content suitable for uranium extraction that could be used in the nuclear fuel cycle.
The miscibility between hydrophobic and hydrophilic biopolymers has been of significant challenge. This study used a novel simplified chitin modification method to produce phthalic chitin using phthalic anhydride in a substitution reaction. The FT-IR functional group analysis was used to confirm the substitution reaction. The modified chitin was used as compatibilizer in polylactic acid (PLA)/starch biocomposite to enhance its properties. The biocomposite was prepared using melt extrusion and compression moulding technique. The biocomposite's morphological, thermomechanical and water absorption properties were characterized using scanning electron microscope, tensile test, dynamic mechanical analysis, thermogravimetry analysis, differential scanning calorimetry, thickness swelling and water absorption test. The FT-IR study shows a successful substitution reaction of the amine hydrogen ion present in the chitin as opposed to substituting the hydrogen ion in the hydroxide group. The tensile and impact properties of biocomposite incorporated with modified chitin showed better results compared with other samples. The SEM images showed uniform miscibility of the modified biocomposite. The dynamic mechanical analysis showed improved modulus value with the incorporation of modified chitin. The thermal properties showed improved thermal stability of the modified biocomposite. Furthermore, the percentage of water absorbed by biocomposite with modified chitin is reduced compared with the PLA/starch biocomposite. The produced biodegradable ternary blend can be used as a substitute for plastics in industrial applications.
In the current research, the resist action of silver-doped polystyrene/polyethylene terephthalate (PET) solar thin film towards laser irradiation was observed. Moreover, silver-doped polystyrene nanoparticles were synthesized via a chemical technique while the PET film was purchased from the commercial market. Nd:YAG pulsed laser has been used to irradiate the samples at 2 minutes, 4 minutes, and 6 minutes respectively. The XRD (X-ray diffraction) pattern shows that silver-doped polystyrene peak at around angle θ = 26° tends to decrease after the bombardment of Nd:YAG pulsed laser. This indicates that the crystallinity of PET film decreased after laser irradiation. The Raman spectra have revealed the zwitter characteristics of silver-doped polystyrene are shifting of bands at 1380 cm-1 and 1560 cm-1 upon laser irradiation. For PET film, the Raman spectra showed that the exposed regions tend to change to cross-linking/chain-scissoring at 2 minutes and 4 minutes of irradiation. The surface roughness first increases and decreases upon irradiation. These results indicate that silver-doped polystyrene/polyethylene terephthalate (PET) thin film is appropriate for solar cell applications.