Effects of Different Concentrations of Biocides on Fungal Populations, Isolated from Biofilms of Corroded Oil Pipelines, Niger Delta Region, Nigeria

Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The present study described fungal enumeration and identification in biofilms of oil pipelines in Oshie flow station in Rivers State and Irri flow station in Delta State, Nigeria using traditional cultivation technique.  The fungal species isolated in biofilms from the two sites are as follows Verticillium dahlae, Saccharomyces cerevisiae, Penicillium corylophilum, Botrytis cinerea, Fusarium oxysporum, Aspergillus paradoxus, Humicola grisae, Aureobasidium pullulans, Monilia balanitis, Hormoconis resinea, Asperillus flavus and Helimenthosporium maydis. The study also focuses on the use of three biocides to inhibit or eliminate the identified organisms in order to minimize the material and financial losses encountered by oil and gas companies, because of microbiologically influenced corrosion (MIC). The performance of three biocides (ozone, sodium hypochlorite and formaldehyde) at the concentrations of 0, 1, 2, 3, 4 and 5% in eliminating the fungal species isolated from biofilms of oil pipelines in Rivers and Delta States, Niger Delta, Nigeria. It is shown, that formaldehyde, ozone exhibited the best biocidal characteristics and concentrations of 1 and 2 % eliminated almost all the fungal species after 72 hours of contact time. This study is relevant to the problem of microbiologically influenced corrosion as the data may contribute to elucidate which fungal species contribute to the MIC process and to gain a better understanding of the fungal community of biofilms. This study will give us better understanding of the biocide capable of eliminating fungal species in biofilm of oil and gas pipelines. Keywords: Concentration, fungal population, biocides, microbiologically influenced corrosion, biofilm

Evaluation of Ductility Index of a Rectangular Beam Reinforced with Rebars Milled from Scrap Metal

Ductility index is essential both in structures and structural elements in service. Its inadequacy may lead to brittle failure and jeopardize the lives of occupants. In reinforced concrete beams that experience large inelastic deformation in service, its ductility index cannot be over- emphasized. In Nigeria, the steel sector is now sustained through the recycling of scrap metal obtained mainly from municipal solid wastes which find application in the construction Industry. The study evaluated the ductility index of a rectangular concrete beam reinforced with rebars milled from scrap metal. This was achieved by designing the beam, produced samples and assessed its behavior under load experimentally and analytically with emphasis on the deflection ductility index. Eighteen (100 mm x 200 mm x 1000 mm) concrete beams reinforced with rebars milled from scrap metal were produced; six each with concrete strength of 20.33, 26, 30 N/mm2 and steel ratio (ρ) of 0.0058 to 0.012 respectively. The samples were tested under a four- point loading and analyzed using the Hognestad models for concrete and steel, theoretical equations of strain compatibility and equilibrium of forces at the beam section. Based on the test data obtained in the laboratory and analytical approach, the failure mode of most beams was classified as ductile flexural failure accompanied by yielding of the tension steel preceding the crushing of concrete. The flexural capacity of the test samples ranged from 43.25 to 88.25 Kn with a deflection ductility index of 1.72 to 2.80. The analytical load-deflection relationship compared with experimental values show good agreement. This confirms the applicability of the theoretical approach which provides a useful tool for evaluating the deflection ductility index and load-deflection response of concrete rectangular beams reinforced with rebars milled from scrap metal. Key words: Ductility index, concrete beams, Rebars, scrap metal, deflection response

Improved Photochemical Performance of Dye-Sensitized Solar Cell using Tectona grandis and Magnifera indica Dye Mix

Communication in Physical Sciences, 2023, 9(2):163-171 Authors: Onen Alfred Ikpi, Etim Emmanuel Edet*, Abah Abah Victor, Ogofotha Godwin Oghenekeno. Received: 02 February 2023/Accepted 05 May 2023 The generation of electrical energy from photo-voltaic conversions was achieved by fabricating a variety of dye-sensitised solar cells (DSSC) using natural dye extracts from Magnifera indica (M. Indica) and Tectona grandis (T. Grandis). This study explores the spectral characteristics of the dyes in Ultraviolet, Visible and infrared regions. An Incident Photon-Current Efficiency (IPCE) of η = 0.0307% was obtained with a short circuit current of up to Jsc = 6.597 mA cm–2, an open circuit voltage of Voc = 0.05 V and a fill factor of 0.537 for the DSSC using the mixed dye. DSSC from M. Indica showed the highest open circuit voltage (Voc) of 0.1V. The efficiency for the DSSC when dyes were individually used was 0.0004 and 0.0241% for T. Grandis and M. Indica dyes respectively

Improved Photochemical Performance of Dye-Sensitized Solar Cell using Tectona grandis and Magnifera indica Dye Mix

Communication in Physical Sciences, 2023, 9(2):163-171 Onen Alfred Ikpi, Etim Emmanuel Edet*, Abah Abah Victor, Ogofotha Godwin Oghenekeno. Received: 02 February 2023/Accepted 05 May 2023 The generation of electrical energy from photo-voltaic conversions was achieved by fabricating a variety of dye-sensitised solar cells (DSSC) using natural dye extracts from Magnifera indica (M. Indica) and Tectona grandis (T. Grandis). This study explores the spectral characteristics of the dyes in Ultraviolet, Visible and infrared regions. An Incident Photon-Current Efficiency (IPCE) of η = 0.0307% was obtained with a short circuit current of up to Jsc = 6.597 mA cm–2, an open circuit voltage of Voc = 0.05 V and a fill factor of 0.537 for the DSSC using the mixed dye. DSSC from M. Indica showed the highest open circuit voltage (Voc) of 0.1V. The efficiency for the DSSC when dyes were individually used was 0.0004 and 0.0241% for T. Grandis and M. Indica dyes respectivel

Antiretroviral Drug Substitution Practice in the Treatment Of HIV/TB Co-Infection

CONCLUSION: This study showed poor compliance with Nigerian treatment protocol for TB/HIV coinfection. Effort to improve TB control in HIV patients are urgently neede