Erosion-corrosion characterisation for pipeline materials using combined acoustic emission and electrochemical monitoring

The prediction and monitoring of erosion and erosion-corrosion attack on oil and gas pipeline materials in service is useful for facilities design, material selection and maintenance planning so as to predict material performance accurately, operate safely, and prevent unplanned production outages. Conventional methods such as failure records, visual inspection, weight-loss coupon analysis, can be time-consuming and can only determine erosion or erosion-corrosion rates when the damage has already occurred. To improve on this, the acoustic emission (AE) technique combined with electrochemical monitoring was chosen and implemented in this study to investigate and characterise erosion and erosion-corrosion degradation rates of oil and gas pipeline materials (X65) under Submerged Impinging Jet (SIJ) systems in a saturated CO2 environment. Measured acoustic emission energy was correlated with the mass loss from gravimetric measurement for different flow velocities and sand loadings. Sand particle impacts were quantified and compared with theoretical predictions, and the associated impact energies predicted from Computational Fluid Dynamics (CFD) were correlated with measured acoustic emission energy and mass loss. The combined acoustic emission and electrochemical monitoring (involving Linear Polarisation Resistance (LPR) and Electrochemical Impedance spectroscopy (EIS)) helped to simultaneously investigate the surface reactivity of the corroding materials as well as capture the sand impacts contribution during the erosion-corrosion degradation processes. Results reveal that the effect of the mechanical damage which is not sensed by in-situ electrochemical measurement is adequately captured by the AE method, thus making the combined technique a novel approach for in-situ monitoring of both the electrochemical and mechanical damage contributions of erosion-corrosion degradation processes

Arthropod Community Structure of Jaja Creek and Downstream Sections of Imo River in Uta Ewa Village, Akwa Ibom State, Nigeria

Arthropods are considered the most successful animals on earth. They are an essential part of the aquatic food chain and efficient bioindicators depicting the biotic community structure and water quality. This study aimed to generate baseline data on the arthropod community structure of Jaja Creek and downstream sections of Imo River in Uta Ewa village, Ikot-Abasi Local Government Area, Akwa-Ibom State, Nigeria. A variety of sampling techniques, including the scoop net method at low tides in the littoral zone, square lift net anchored on a paddling boat, sweep net, and locally made crab traps were adopted for the sampling of the arthropods. Fourty-six arthropod species were identified and classified into three classes: Arachnida, Crustaceans, and Insecta, with nine orders and twenty-six families. Sesarma alberti, Aratus pisonii, Sesarma elegans, Armases sp, Neosarmatium meinerti, Nematopalaemon sp, and Macrobrachium caledonicum were among the various arthropod species identified in this study. The class Crustaceans had the highest individual abundance of 135,809 (94.74%), followed by the class Insecta, which had a total numerical individual abundance of 7,339 (5.12%), and the order Arachnida (206; 0.14%). For the first time, members of the class Insecta and the families Sesarmidae, Pilumnidae, and Penaeidae (Penaeus sp.) were collected and identified in this portion of the Niger Delta Creek and Imo River. Given the importance of aquatic arthropod species to the catchment region and the country, a comprehensive conservation strategy should be developed to conserve and defend their survival

Improving food safety culture in Nigeria:A review of practical issues

As a developing nation and the most populous nation in Africa, Nigeria has enormous challenges connected with food safety culture. To produce and provide safe, secure and nutritious food, consumers and food businesses must abide by a set of shared values known as food safety culture. In Nigeria, food safety culture is a complex subject due to Nigeria’s heterogeneous and diverse nature, as demonstrated by its over 250 ethnic groups. As Nigeria becomes more urbanized and incomes continue to fluctuate at robust rates, few Nigerians are conscious of food safety issues. In addition, oversight from government regulators around food safety require improvement. Public engagement in food safety issues has not witnessed a promising trajectory in recent years. In this article, we provide a review of the food safety culture in Nigeria and its role and influence on various cases of food safety issues in Nigeria. Of interest to this paper are studies exploring consumer and food handler perceptions and behavior regarding food safety. In addition, keen attention is devoted to areas that are in need of additional research to help address practical and on-the-ground challenges associated with Nigeria’s food safety practices. This article suggests that improving food safety culture in Nigeria requires both applying the best management and communication approaches in different regions and understanding the local food safety practices

Intestinal schistosomiasis and contributory risk factors in Nsu, Ehime Mbano LGA Imo State, Nigeria

The prevalence of intestinal schistosomiasis was determined in three communities in Nsu, Ehime Mbano Local Government Area, Imo State using structured questionnaires for demographic data collection and faecal analysis for detecting the presence of Schistosoma mansoni ova. Examination for the presence of S. mansoni was done using formol-ether concentration technique and microscopy. Out of the 476 persons examined comprising 268 males and 208 females, 24 (5.04%) had their faecal samples positive for S. mansoni infection. More males (5.97%) than females (3.85%) were infected. The highest prevalence occurred in persons aged 15-29 years (5.82%) followed by persons aged 0-14 years (5.76%). Infected persons were mostly students (5.67%) and farmers (5.55%). There was a significant association between occupation and infection(x2 51.84, p>0.05). Source of water used seemed to play a contributory role to infection. Infection occurred most among those that used the stream as their source of water (6.73%). Regarding toilet facilities, those who defaecated in the bush had the highest rate of infection (5.37%). The result of this study has revealed the presence of intestinal schistosomiasis in Nsu. It would be aptly appropriate for the infected persons to seek treatment at the local health centre and the government possibly consider including Nsu in the schistosomiasis control programme, though prevalence was below 50%. This is to help prevent further spread of the infection and control possible morbidity and resultant socio-economic effects that may arise there from.Keywords: intestinal schistosomiasis, Nsu, prevalence, risk factors

Auditing: A Strategy Evaluation Emphasis

This research investigated whether or not auditing is useful to the strategy evaluation and control process in Nigerian business organizations. In sourcing for data, we used structured questionnaire as well as personal interviews. The data collected were analyzed using the simple percentage and frequency distribution. We found that effective internal audit helps in the strategy evaluation and control process in the organizations we studied. Our conclusion is that, the effective performance of internal audit is crucial for management to be able to evaluate and control strategy in modern organization. SOPHIA: An African Journal of Philosophy Vol. 8 (2) 2006: pp. 109-11

Estimating Production Function with Economic Content Using Data Envelopment Analysis as a Complement to Marginal Analysis in Rice Production of Kwara State, Nigeria

The consideration in the present study is mainly conceptual. The objective is to show how Data Envelopment Analysis (DEA) can be used to reveal the true input-output relations in rice production. In the estimation of a production function, it is assumed that all firms use the existing technology efficiently. However, in the real world the observed firms produce homogeneous outputs with differences in factor intensities and in managerial capacity. Hence, inefficiencies are hidden in the estimated production functions. In order to overcome this drawback of the parametric approach and to reveal the true nature of the input-output relations in production, given the available technology, the DEA approach is applied. In this study DEA is applied in order to select the farms that utilize efficiently the existing technology, allowing the estimation of a production function that reveals the true input-output relations in rice farming, using farm accounting data from a sample of 60 rice farms. Keywords: Data envelopment analysis; production function; parametric approac

SOME BEHAVIOURAL RESPONSES OF LIMICOLARIA AURORA EXPOSED TO GRAMOXONE

The effects of 0.5 , 1.0 , 1.5 and 2.0 % of combined oral and dermal single-application of 0.1 M concentration of gramoxone (contact herbicide, paraquat chloride) on Limicolaria aurora were determined and compared with control using Amaranthus sp. as bait. Responses were measured through normal feeding and crawling, head retraction into the shell, swelling, excessive mucus secretion, lack of response to mechanical stimuli (mortality). Results showed no effects on controls. Snails exposed to gramoxone fed less as contamination increased. Gramoxone is molluscicidal, it can also result in behaviour-modifying observations in snails which are non-target organisms in the ecosystem