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Olive Mill Solid Residue (OMSR) can be utilized as a bio-sorbent in wastewater treatment. Even though several studies on OMSR as a bio-sorbent were carried out, there is still a need to investigate a simple and relatively inexpensive OMSR treatment that increases pollutant removal. In this study; OMSR is used in batch experiments to remove toxic heavy metals from aqueous solutions including Cd2+, Cu2+, and Pb2+ ions. The effect of OMSR treatment (untreated; OMSR-U, treated with n-hexane; OMSR-H, and treated with water; OMSR-W) was investigated by chemical oxygen demand and cation exchange capacity. It was confirmed by both tests that OMSR-W was the best treatment. The same result was re-confirmed by batch uptake experiments of the heavy metal ions. Using OMSR-W as a bio-sorbent; the effect of several parameters such as pH, contact time, bio-sorbent concentration, metal ions concentration, and the presence of other metal species were studied to figure their influence on the metal ions uptake. The optimum conditions for single metal systems were found to occur at pH 5.5, an initial metal concentration of 50 mg/L, a shaking time of 60 minutes, a bio-sorbent concentration of 20 g/L. In binary metal ions solutions; Cd2+ uptake was increased in presence of Cu2+ or Pb2+. However, the uptake of Cu2+ and Pb2+ was decreased in presence of other metals. The equilibrium sorption data for single metal systems were described by the Langmuir isotherm model. The highest value of maximum uptake was found for Pb2+ (4.587 mg/g) followed by Cd2+ (4.525 mg/g) and Cu2+ (4.367 mg/g). These results show that OMSR-W, which has a very low economical value, could be used for the treatment of wastewater contaminated with heavy metals.

Classical trajectory calculations for various atom-diatomic molecules were preformed using the three-dimensional Monte Carlo method. The reaction probabilities, cross-sections and rate constants of several systems were calculated. Equations of motion, which predict the positions and momenta of the colliding particles after each step, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecules. The results were compared with experimental ones and with other theoretical values. Good agreement was obtained between calculated rate constants and those obtained experimentally. Also, reasonable agreement was observed with theoretical rate constants obtained by other investigators using different calculation methods. The effects of the temperature, the nature of the colliding particles and the thermochemistry were studied. The results showed a strong dependence of the reaction rates on these factors.

A sensitive and simple sample pretreatment method based on a two-phase solvent bar microextraction (SBME) technique coupled with HPLC-diode array detector (DAD) was developed for simultaneous extraction and determination of trace amounts of furosemide and carbamazepine in human urine and plasma samples. The significance of operational factors on carbamazepine and furosemide extraction efficiency % (EE%) was screened using full factorial design (FFD) while central composite design (CCD) was used to model the entire process. A quadratic model was found convenient to correlate the extraction EE% of selected drugs with dominant experimental factors. A Pareto chart was also used to examine the importance of factors on drugs' EE%. The analytical performance of the method in urine and plasma samples demonstrated good linearity (R 2 > 0.992) with detection limits ranging from 4.2 to 10.9 μg L À1 , and extraction recovery over 89.45% for both drugs in urine and plasma samples. A comparison against published methods was also performed and the results revealed that the developed method exhibits a confident sensitivity, feasible operation, and simple analysis for both drugs. Finally, the practicability of the validated SBME-HPLC-DAD method was demonstrated by successfully applying it to the analysis of furosemide and carbamazepine in real patient urine samples.biological matrices, central composite design, design of experiment, furosemide and carbamazepine, HPLC-DAD, solvent bar microextraction | INTRODUCTIONFurosemide (FUR), 4-chloro-N-furfuryl-5-sulfamoyl-anthranilic acid, is a potent loop diuretic and frequently used in the treatment of edematous states related to chronic failure, hypertension, or cirrhosis of the liver (Krisanapan et al., 2020). FUR is rapidly but incompletely absorbed after oral administration and highly bound to plasma proteins (>90%; Wenk et al., 2006), with up to 50% of a dose eliminated by urinary excretion, mainly as an unchanged drug (Oh & Han, 2015). Carbamazepine (CBZ), 5-H-dibenze[b,f]azepine-5-carboxamide, is a tricyclic lipophilic compound used as an anticonvulsant and mood-stabilizing drug in the treatment and prevention of seizures caused by epilepsy (Lawthom et al., 2018). After oral administration,