The corrosion inhibition of ampicillin (AMP) and its synergistic combination with halides (KI, KCl and KBr) for the corrosion of mild steel in H 2 SO 4 have been investigated using gravimetric, gasometric, thermometric and infrared (IR) methods. The inhibition efficiencies of AMP for the corrosion of mild steel increased with increase in concentration but decreased with rise in temperature. The adsorption of AMP on the mild steel surface was found to obey the Langmuir adsorption isotherm model. The combination of AMP with the halides (KI, KBr and KCl) enhanced the inhibition efficiency and adsorption behavior of the inhibitor indicating synergism. The inhibition efficiency of AMP increased with increasing concentration and the adsorption of the inhibitor was spontaneous. Physical adsorption mechanism has been proposed from the thermodynamic data obtained. There was a significant correlation between the inhibition efficiency of AMP and some quantum chemical parameters (R 2 = 0.96) using the quantitative structure-activity relationship (QSAR) method. Some quantum chemical parameters and the Mulliken charge densities on the optimized structure of AMP were calculated using the B3LYP/6-31G (d,p) basis set method to provide further insight into the mechanism of the corrosion inhibition process.

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The inhibition efficiency of some antibiotics against mild steel corrosion was studied using weight loss and quantum chemical techniques. Values of inhibition efficiency obtained from weight loss measurements correlated strongly with theoretical values obtained through semi empirical calculations. High correlation coefficients were also obtained between inhibition efficiency of the antibiotics and some quantum chemical parameters, including frontier orbital (E (HOMO) and E (LUMO)), dipole moment, log P, TNC and LSER parameters (critical volume and dipolar-polarisability factor), which indicated that these parameters affect the inhibition efficiency of the compounds. It was also found that quantitative structure activity relation can be used to adequately predict the inhibition effectiveness of these compounds.

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Petroleum exploration and production in the Nigeria's Niger Delta region and export of oil and gas resources by the petroleum sector has substantially improved the nation's economy over the past five decades. However, activities associated with petroleum exploration, development and production operations have local detrimental and significant impacts on the atmosphere, soils and sediments, surface and groundwater, marine environment and terrestrial ecosystems in the Niger Delta. Discharges of petroleum hydrocarbon and petroleumderived waste streams have caused environmental pollution, adverse human health effects, socioeconomic problems and degradation of host communities in the 9 oil-producing states in the Niger Delta region. Many approaches have been developed for the management of environmental impacts of petroleum production-related activities and several environmental laws have been institutionalized to regulate the Nigerian petroleum industry. However, the existing statutory laws and regulations for environmental protection appear to be grossly inadequate and some of the multinational oil companies operating in the Niger Delta region have failed to adopt sustainable practices to prevent environmental pollution. This review examines the implications of multinational oil companies operations and further highlights some of the past and present environmental issues associated with petroleum exploitation and production in the Nigeria's Niger Delta. Although effective understanding of petroleum production and associated environmental degradation is importance for developing management strategies, there is a need for more multidisciplinary approaches for sustainable risk mitigation and effective environmental protection of the oilproducing host communities in the Niger Delta.

Global flaring and venting of petroleum-associated gas is a significant source of greenhouse gas emissions and airborne contaminants that has proven difficult to mitigate over the years. In the petroleum industry, poor efficiency in the flare systems often result in incomplete combustion which produces a variety of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) and inorganic contaminants. Over the past fifty years, gas flaring and venting associated with petroleum exploration and production in the Nigeria's Niger Delta has continue to generate complex consequences in terms of energy, human health, natural environment, socioeconomic environment and sustainable development. In some oil-producing host communities, most flaring and ventingsystems are located in close proximity to residential areas and/or farmlands; and the resultant emissions potentially contribute to global warming as well as somelocal and/or regional adverse environmental impacts.There are emerging facts in an attempt to understand the effect of flaring and venting practices and the complex interactions of thermal pollution, organic and inorganic contaminants emission in the environment. This review discusses environmental contamination, adverse human health consequences, socioeconomic problems, degradation of host communities and other associated impacts of flaring and venting of associated gas in the petroleum industry in the Niger Delta. Effective understanding of the overall impact of associated gas flaring and venting in the petroleum industry is important for effective management of the energy resources, environmental risk mitigation, implementation of good governanceand sustainable development.

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