Mervate Mohamed Mohamed

The study's goal is to prepare bioplastic by corn starch environmentally favorable. Corn Water, gelatin, glycerin, a food coloring coconut oil, and cotton were used to make bioplastic. The data demonstrate that bioplastic is biodegradable, with an average weight loss of 57.9%. It was partially soluble in ethanol and water but totally soluble in HCl. Swelling test showed no change when immersed in chloroform, but a slight change in water. It degrades more quickly as temperatures rise. The thermodynamic parameters results that the activation energy ΔEa was 36.5 Jmol-1,the positive values of Gibbs energy, entropy ΔS had suggesting non-spontaneous and less organized structure behavior and a negative ΔH value indicating exothermic nature.The rate of kinetic rises as the starch concentration increased. The manufactured bioplastic possesses features such as minimum swelling and is insoluble in water. Corn starch will be making it commercially feasible and a renewable resource.

The detection of organophosphorus pesticides, particularly chlorpyrifos, in environmental samples is essential due to their widespread use and associated health risks. In this study, we developed a high-sensitivity fluorescent sensing platform utilizing an Isatin-3-allyl-terbium (IS-Tb) complex in solution for the rapid and selective detection of chlorpyrifos in various water samples. The proposed chemical structure of the complex in solution was evaluated using molar ratio method. The IS-Tb complex was characterized in solution, as it was not isolated in the solid state. To assess its structural and optical properties, several characterization techniques were employed. UV-Vis spectrophotometry was used to evaluate the absorption characteristics, and spectrofluorimetry was applied to assess the fluorescence properties. Additionally, the stoichiometry of the complex was determined using the molar ratio method, which confirmed a 1:1 ligand-to-metal ratio and provided the optimal conditions for sensing chlorpyrifos. The IS-Tb complex exhibited weak intrinsic fluorescence, which was significantly enhanced upon interaction with chlorpyrifos, enabling sensitive and quantitative analysis. Methanol was identified as the best solvent for maximizing the sensitivity of chlorpyrifos detection. The sensor demonstrated a wide linear detection range from 0.006 to 28 µg/L, with a low limit of detection (LOD) of 2 ng/L. The sensor’s selectivity for chlorpyrifos over other commonly encountered pesticides (13 organophosphorus) and environmental contaminants was high, ensuring minimal interference. The performance of the sensor was validated using spiked water samples, yielding an average recovery of 101% with a relative standard deviation (RSD) of less than 5%. These results suggest that the proposed sensing platform is a powerful tool for the environmental monitoring of chlorpyrifos, with significant implications for public health protection and regulatory compliance.

A new lactate bath was proposed to deposit Co–Cu thin alloy films in nanostructure form onto a steel cathode. The deposition bath contained CuSO₄.5H₂O, CoSO₄.7H₂O, CH₃CHOHCOOH, and anhydrous Na₂SO₄ at pH 10. The effects of [Co²⁺]/[Cu²⁺] molar ratios, lactate ion concentration, current density (CD), and bath temperature on cathodic polarization, cathodic current efficacy (CCE), composition, and structure of the Co–Cu alloys were investigated. The new bath had a high cathodic current efficiency of 85%, which increased with the applied CD. However, it decreased as the temperature increased. The produced coatings have an atomic percentage of Cu ranging from 19.8 to 99%. The deposition of the Co–Cu alloy belonged to regular codeposition. The Co content of the deposit increased with the amount of Co²⁺ ions in the bath, lactate concentration, and current density but decreased as the temperature increased. Cobalt hexagonal close-packed (HCP) and copper-rich, face-centered cubic (FCC) Co–Cu phases combine to form the polycrystalline structure of the electrodeposited Co–Cu alloy. The average crystallite size ranges between 46 and 89 nm. An energy dispersive X-ray (EDX) examination confirmed that the deposit contained Cu and Co metals. The throwing power and throwing index of the alkaline lactate bath were evaluated and found to be satisfactory.

In this work, we studied the corrosion of Cu metal in 0.5 mol L⁻¹ HCl and the inhibition effect of the expired Cefazolin drug. The inhibition efficiency (IE) of Cefazolin varied according to its concentration in solution. As the Cefazolin concentration increased to 300 ppm, the IE increased to 87% at 298 K and decreased to 78% as the temperature increased to 318 K. The expired drug functioned as a mixed–type inhibitor. The adsorption of the drug on the copper surface followed Temkin’s adsorption model. The magnitudes of the standard free energy change (ΔG^o_ads) and adsorption equilibrium constant (K_ads) indicated the spontaneous nature and exothermicity of the adsorption process. Energy dispersive X-ray (EDX) and scanning electron microscopy (SEM) techniques showed that the drug molecules were strongly attached to the Cu surface. The electrochemical frequency modulation (EFM), potentiodynamic polarization (PP), and electrochemical impedance spectroscopy (EIS) results were in good agreement with the results of the weight loss (WL) method. The density functional tight–binding (DFTB) and Monte Carlo (MC) simulation results indicated that the expired drug bound to the copper surface through the lone pair of electrons of the heteroatoms as well as the π-electrons of the tetrazole ring. The adsorption energy between the drug and copper metal was –459.38 kJ mol⁻¹.

This study focussed on the dyeing wool fabrics with colourant purple Brassica oleracea var. capitata F. rubra. The process of dyeing was taken place at 60 ºC and pH 5. Adsorption and desorption isotherms experiments investigated by Langmuir and Frendulich models, Langmuir was fitted with the experimental data dyeing adsorption than Freundlich model. The adsorption kinetic of dyeing experiments was studied by using pseudo-first and pseudo-second models and pseudo-second model was more suitable for wool dyeing experiment. The thermal stability of the dye (purple Brassica oleracea var. capitata F. rubra) was studied using thermogravimetric and differential thermal (TGA/DTG) analysis. The antimicrobial activity of purple cabbage methanolic extract recorded of high exhibited Staphylococus aureus (17-18 mm), weak against fungi (11-12 mm), moderate against Bacillus subtilis (14-15 mm) and no results against Escherichia coli. The results obtained from aqueous and petroleum were negative.