Lead accumulation by hammerhead shark, Sphyrna couardi (C.) off Lagos coast, Nigeria

Levels of concentration of lead in the hammerhead shark, Sphyrna couardi, off the Lagos Coast of Nigeria were investigated. The standard length of the specimens examined ranged from 31.4cm to 47.2cm while the weights ranged from 451.5 to 1,667g. The lead concentration ranged from 0.11 degree kg/G to 0.38 degree kg/G. The mean lead concentration was 0.56 degree kg/G (dry weight). The gill has the highest lead concentration. There was no linear correlation between the length and weight and the amount of lead concentrate

Thermodynamic Analysis of a Gas Turbine Power Plant Modelled with an Evaporative Cooler

Performance of a gas turbine is mainly depends on the inlet air temperature. The power output of a gas turbine depends on the flow of mass through it. Inlet air cooling increases the power output by taking advantage of the gas turbine’s feature of higher mass flow rate when the compressor inlet temperature decreases. This is precisely the reason why on hot days, when air is less dense, power output falls off. A rise of 1°C temperature of inlet air decreases the power output by 1%. In this paper the performance enhancement of gas turbine power plants by cooling the compressor intake air with an evaporative cooler is studied. This study investigated the effect of inlet air cooling system on the performance of an existing gas turbine power plant in Nigeria. The results show that for each 5oC decrease of inlet air temperature, net output power increases around 5-10% and the first and second law efficiencies increase around 2-5%. It is shown that the amount of this increase is higher when the pressure ratio is high and turbine inlet temperature is low. The results of this study shows that retrofitting of the existing gas turbine plant with inlet air cooling system gives a better system performance and may prove to be an attractive investment opportunity to the Nigeria government and stakeholders of the plant

Proximate composition, structural characterization and phytochemical screening of the seed oil of Adenanthera pavonina linn

Adenanthera pavonina is leguminous species which is a perennial and non-climbing tree which is a highly valuable plant for food, drink, and traditional medicine. The Adenanthera pavonina Linn Seed was obtained in our institution premises. This present study was targeted at evaluating proximate analysis, phytochemical determination, a physicochemical parameter of the spectroscopically characterized oil sample of Adenanthera pavonina. The oil which was extracted by standard method had percentage yield of 15.36%. The phytochemical screening of the oil revealed the presence of saponin, alkaloid, and terpenoids. Proximate analysis result unveiled that seed oil of Adenanthera pavonina Linn had an appreciable quantity of protein 27.72%, Crude fiber 5.82 and Ash contents 2.51. It also showed the moisture content, organic matter, carbohydrate, pH and Refractive index to be 13.34%, 97.49% 54.36%, 5.96 and 1.62 respectively. The mineral determination showed that the seed oil contained Manganese (0.001 ± 0.0002 %), Iron (13.52 mg/kg), while Potassium (K), Sodium (Na), Nickel (Ni), Chromium (Cr), Cobalt (Co), Lead (Pb) and Cadmium (Cd) were below the detectable limit. The structure of the oil was elucidated using physicochemical analyses and spectral data which include FT-IR, UV, 1H- and 13C-NMR as well as mass spectral data. The spectroscopic data correlated well and was consistent with the proposed structure. The seed oil could provide access to increase dietary formulation owing to its high protein content. Keyword

Adsorption Behaviour of [(4-Hydroxy-6-methyl-2-oxo-2Hpyran- 3-yl)-(4-methoxy-phenyl)-1methyl]-urea on Stainless Steel in Phosphoric Media

The adsorption of [(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-(4-methoxy-phenyl)- methyl]-urea on iron in phosphoric media was studied by using electrochemical technique. The adsorption mechanism was investigated using adsorption isotherms. The experimental data fit localized adsorption models. The values for free energy of adsorption, o DGads , were also calculated at each surface coverage, �, of the studied compound by applying the mathematical model of Bockris – Swinkels adsorption isotherm. The variation of free energy of adsorption o ads DG with surface coverage, �, was interpreted in terms of deviation from ideal condition assumed in Langmuir model. A possible adsorption model of HPU2 molecules on to the metal surface was suggested