No abstract

No abstract

Theoretical studies were carried out to investigate the thermal decomposition of ethyl dithiocarbonates (xanthate) using Hartree-Fock at the HF/321-G* level and the density functional method with Becke 3 Lee Yang pair DFT/(B3LYP), 6-31G*, 6-31G**, 6-31+G*, MP2 and CCSD in the ab initio method of calculation using Spartan 10. Geometric parameters, such as the bond length, bond angles, dihedral angles, heat of formation, atomic charges and vibrational frequencies, were obtained. The data were used to calculate the thermodynamics parameters, change in entropy S, enthalpy change H, free energy G, pre-exponential factor A, rate k at 623 K, and variation of rate k with temperatures from 498-623 K at temperature intervals of 25 K. It was observed that the values obtained are in good agreement with the experimental values for the ab initio methods, and according to Arrhenius theory, the calculated rate k increases with increasing temperature.

The mechanisms, kinetics and thermodynamics of the gas-phase pyrolysis of sec-butyl bromide at 623K was carried out using Density Functional Theory (DFT) with B3LYP at 6-311++G (2df, 2p) level method. The result showed that the pyrolysis of sec-butyl bromide proceeds through a fourmembered cyclic transition state which involved a C 10 -H 11 and C 8 -Br 14 bond breaking and H x -Br 14 (H x = H 11 , H 6 and H 7 for n-butene, trans and cis-2-butene) bond making. The calculated data [∆H *

Some legumes are commonly used as commercial food crops in West Africa while others are lesser known, neglected or underutilized. This research work is aimed at the evaluation of the chemical compositions and possible utilization of the legume Lablab purpureus and Phaseolus lunatus samples to solve metabolic diseases.  The evaluation of the chemical compositions and glycemic index (GI) of both seeds were carried out using standard methods. Phytochemical screening conducted on the seeds showed the presence of tannin, saponin, alkaloid and flavonoids in both samples. The results of antioxidant properties of the seeds showed that Phaseolu slunatus and Lablab purpureushave Vitamin C (35.01 ± 0.02 and8.75± 0.03)mg/g, ferric reducing property (20.54 ± 0.02and 12.75 ± 0.03)mg/g, phenol (2.02 ± 0.02 and 2.05 ± 0.02)mg/g, flavonoids (3.47 ± 0.11 and3.22 ± 0.02) % andfree radical scavenging property (46.52 ±0.05 and 60.16 ±0.32)% respectively.The anti-nutrient results showed tannin (1.07 ± 0.01 and 1.22 ± 0.02)%, saponin (4.66 ± 0.05 and 5.15 5.15 ± 0.05)%, oxalate (3.20 ± 0.19 and 5.19 ± 0.19)mg/g, phytate(6.51 ± 0.01 and 2.64 ± 0.01) % for Lablab purpureus and Phaseoluslunatusseeds are respectively.The glycemic indices observed are ( 50.86 and 58.21)% forLablab purpureus and Phaseoluslunatusseeds respectively. The findings revealed that both seeds possessed good nutritional quality required in human diet together with adequate antioxidant properties plus low and medium glycemic indices  that could help in fighting various cardiovascular diseases and prove them to be good sources of neutraceuticals required for a healthy living especially in diabetic patients.