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Corrosion is a major concern for many industries that use metals as structural or functional materials, and the use of corrosion inhibitors is a widely accepted strategy to protect metals from deterioration in corrosive environments. Moreover, the toxic nature, non-biodegradability and price of most conventional corrosion inhibitors have encouraged the application of greener and more sustainable options, with natural and synthetic drugs being major actors. Hence, this paper aims to stress the capability of natural and synthetic drugs as manageable and sustainable, environmentally friendly solutions to the problem of metal corrosion.

In this review, the recent developments in the use of natural and synthetic drugs as corrosion inhibitors are explored in detail to highlight the key advancements and drawbacks towards the advantageous utilization of drugs as corrosion inhibitors.

Corrosion is a critical issue in numerous modern applications, and conventional strategies of corrosion inhibition include the use of toxic and environmentally harmful chemicals. As greener alternatives, natural compounds like plant extracts, essential oils and biopolymers, as well as synthetic drugs, are highlighted in this review. In addition, the advantages and disadvantages of these compounds, as well as their effectiveness in preventing corrosion, are discussed in the review.

This survey stresses on the most recent abilities of natural and synthetic drugs as viable and sustainable, environmentally friendly solutions to the problem of metal corrosion, thus expanding the general knowledge of green corrosion inhibitors.

This study aims to develop eco-friendly corrosion inhibitors for aluminum in acidic media by evaluating the corrosion inhibition properties of corn leaf extract (CLE) using response surface methodology (RSM) and experiments.

The RSM was combined with experiments to evaluate the corrosion inhibition properties of CLE on aluminum in acid media.

The effectiveness of the inhibition increased with increasing inhibitor concentration and time but decreased with increasing temperature. The corrosion inhibition mechanism revealed the corrosion process is spontaneous exothermic physical adsorption. Thermodynamic parameters revealed an activation energy between 32.1 and 24.7 kJ/mol, energy of adsorption between −14.53 and −65.07 and Gibbs free energy of −10.12 kJ/mol which indicated the CLE exothermically spontaneously physisorbed. A model was generated to estimate the effect of the process parameters (inhibitor concentration, reaction time and temperature) using the RSM. Optimization of the process factors was also carried out using the RSM. The percentage inhibition efficiency obtained experimentally (85.61%) was closely comparable to 84.89% obtained by the theoretical technique (RSM). The SEM observations of the inhibited and uninhibited Al samples demonstrated that CLE is an effective corrosion inhibitor for aluminum in acid media.

Results herein provide novel information on the possible application of CLEs as effective eco-friendly corrosion inhibitors.

Previous studies have postulated that an advance payment system (APS) positively impacts the contractor's working capital and is paramount to ensuring an efficient and effective project cash flow process. However, scant research has been undertaken to empirically establish the cash flow performance and domino effect of APS on project and organisational performance.

The epistemological design adopted a positivist philosophical stance augmented by deductive reasoning to explore the phenomena under investigation. Primary quantitative data were collected from 504 Construction Industry Development Board (CIDB) registered contractors (within the grade bandings 1–9) in South Africa. A five-point Likert scale was utilised, and subsequent data accrued were analysed using structural equation modelling (SEM).

Emergent findings reveal that the mandatory use of an APS does not guarantee a positive project cash flow, an improvement in organisational performance or an improvement in project performance.

The ensuing discussion reveals the contributory influence of APS on positive cash flow and organisational performance, although APS implementation alone will not achieve these objectives. Practically, the research accentuates the need for various measures to be concurrently adopted (including APS) towards ensuring a positive project cash flow and improved organisational and project performance.

There is limited empirical research on cash flow performance and the domino effect of APS on project and organisational performance in South Africa, nor indeed, the wider geographical location of Africa as a continent. This study addresses this gap in the prevailing body of knowledge.

The purpose of this study was to investigate the likely causes of failure of some sections of road pavements in Ajaokuta, Northcentral Nigeria. This was achieved through a geotechnical assessment of subgrade soils in affected areas.

The methods entailed field and laboratory methods and statistical analysis. Subgrade soil samples were retrieved from a depth of 1,000 mm beneath the failed portions using a hang auger. The soils were analyzed for natural moisture content (NMC), Atterberg limit (liquid limit, plastic limit and linear shrinkage), grain size distribution, compaction and California bearing ratio (CBR), respectively.

The results of the geotechnical tests ranged from NMC (12.5%–19.4%), sand (84%–98%), fines (2%–16%), LL (16.0%–32.2%), PL (17%–27.5%), LS (2.7%–6.4%), PI (2.5%–18.4%), maximum dry density (1756 kg/m2–1961 kg/m2), optimum moisture content (13.2%–20.2%), unsoaked CBR (15.5%–30.5%) and soaked CBR (8%–22%), respectively. Pearson’s correlation coefficient performed on the variables showed that some parameters exhibited a strong positive correlation with r2 > 0.5.

Funding was the main limitation.

Comparing the results with Nigerian standards for road construction, and the AASHTO classification scheme, the subgrade soils are competent and possess excellent to good properties. The soils also exhibited very low plasticity, a high percentage of sand, high CBR and low NMC, which implies that it has the strength required for road pavement subgrades. The likely causes of the failures are, therefore, due to the use of poor construction materials, technical incompetence and poor compaction of sub-base materials, respectively.

Enhancing household consumption and reducing inequality are among the fundamental goals of many developing countries. The purpose of this study therefore is to disaggregate household consumption expenditure into food and non-food and, thus, decompose inequality into within- and between-groups.

The study adopts generalised entropy (GE) measures. Second, the study uses regression-based inequality decomposition to ascertain the determinants of inequality in food and non-food expenditure using household demographic and socioeconomic characteristics as covariates.

The results show that non-food expenditure is the major source of inequality in household consumption expenditure in both urban and rural areas with inequality coefficients of above 0.6 compared to about 0.4 for food expenditure. The decompositions also show that within-group inequalities for non-food and food expenditure are, respectively, 0.97 and 0.365 using the Theil index, while between-group inequalities for non-food and food are, respectively, 0.016 and 0.035. Furthermore, the regression-based inequality decompositions show that variables such as living in rural areas, household size, household dwelling and household dwelling characteristics account for the significant proportion of inequality in food and non-food expenditure.

The policy implication of the findings, among others, is that policies should focus on addressing inequality within rural and urban areas, especially with respect to non-food expenditure than in inequality existing between urban and rural areas. These non-food expenditures include expenditure in education, health, energy, accommodation, water and sanitation.

The purpose of this paper is to critically examine the Economic and Financial Crime Act 2004 to investigate whether there are defects in the 2004 Acts which enable abuse of the system by those who are responsible for fighting corruption and other economic crimes in Nigeria.

The paper adopts qualitative methods of research. The research studied the laws and regulations relevant to the recovery and management of proceeds of crime. However, personal experience of the author in the civil service, security and law enforcement accounts significantly.

The paper finds that the provisions of the EFCC Act 2004 relevant to the recovery of proceeds of crime and management of recovered assets are defective. The 2004 Act contains loopholes that enable mismanagement and diversion of recovered assets for personal use. Although the EFCC Act empowers the Minister of Justice to issue Regulations to regulate the activities of the EFCC, the Asset Tracing, Recovery and Management Regulations 2019 the Minister of Justice issued cannot be used to close the loopholes. Thus, there is an urgent need to amend the EFCC Act 2004.

Non-availability of data on the mismanagement of seized and recovered assets is a severe limitation. Thus, analysis in this research focuses on the laws and regulations to illustrates the defects in the 2004 Act. Also, the study could only use reported cases and incidence of corruption among the security and law enforcement to illustrate unsuitability of security and law enforcement for the position of the chairman of the EFCC.

There is no comprehensive work that examines the defects of the provisions of the 2004 Act that breeds lack of transparency in the recovery of proceeds of crime as well as mismanagement of recovered assets. Therefore, this paper is of value to the Nigerian Government and the National Assembly in considering amendments to the EFCC Act 2004. The paper is also of importance to researchers.

Leadership is basically about influence and ability to cultivate followership. This chapter examined the nature of indigenous socio-political leadership in Africa using Zimbabwe, Sudan and Nigeria as caselets and compared this with the post-colonial or modern-day leadership realities. A survey was conducted among senior executives at Lagos Business School, Nigeria, with a sample size of 200 persons, to find out their perception of the African indigenous leadership system. An overwhelming 90% believe that culture plays a big role in shaping African leadership style. However, two-thirds of the respondents agreed that Africa lacks proper institutional structures to support good leadership, thus encouraging corruption (97% of the respondents) and non-accountability among the leaders. Also, only 5% thought cultural orientation was the reason why the African followers do not hold their leaders accountable. In other words, it is not in the African culture not to hold leaders accountable for their actions. So, what went wrong? We attempted a deeper look at the effect of colonial rule and the attendant militarisation of the African continent. Our conclusion is that the colonisation of the continent by Europe brought significant distortion to the traditional African indigenous leadership institutions and the psyche of the African leader and the followers alike. Post-colonial Africa has witnessed 133 recorded coups d’etat between 1952 and 2016. This chapter is recommended to all those who seek a deeper understanding of the nature of the African indigenous leadership practices and the factors that have shaped these over the years.

This paper aims to assess if the Economic and Financial Crimes Commission (EFCC) has been effective in combating corruption in Nigeria from 2003-2012.

The paper adopted a documentary analytical approach.

The organization has not been effective in combating corruption in Nigeria.

The study is between 2003-2012.

There is a need to correct those identified inhibitors that undermined the Commission’s capacity, such as intrusive government interference, lack of autonomy, poor funding and weak laws, among others, to mitigate corruption.

Eliminating those identified constraints will remove the incentive to be corrupt, thereby curbing the desire to be corrupt.

This paper is an original assessment of the EFCC's effectiveness in combating corruption in Nigeria during the specified period.

The demand for aluminium alloys has been increasing in almost all the fields. In this study, the friction stir welding (FSW) of similar aluminium alloy AA 8011-h14 has been presented using three levels of tool rotational speed (n), tool tilt angle (ϴ) and tool feed (f). The purpose of this paper is to study the effect of welding parameters on various properties and time-temperature plots.

FSW was carried out using the L-9 orthogonal array of welding parameters generated using the Taguchi approach. Visual inspection and radiography testing were conducted to detect the surface and volume defects, respectively. Taguchi analysis was carried out to get optimised welding parameters for tensile testing. The microstructural analysis was carried out for the specimen possessing maximum tensile strength and the obtained grain structures were compared with the microstructure results of the base material. The peak process temperatures were noted and time-temperature plots were analysed for the varying parameters. The maximum value of hardness was recorded and analysed.

Visual inspection and radiography testing confirmed defect-free joints. The maximum tensile strength achieved was 84.44 MPa with 64.95 per cent efficiency. The optimised parameters obtained using Taguchi analysis for tensile testing were 1,500 rpm, 1° and 50 mm/min. Microstructure analysis for the specimen possessing maximum tensile strength revealed fine and equiaxed grains in the nugget zone. Time-temperature plots suggested the maximum temperature of 389 °C on the advancing side. A maximum hardness value of 36.4 HV was obtained in the nugget zone.

As per the knowledge of the authors, this study is the first attempt for the detailed experimental analysis on the FSW of this particular aluminium alloy AA 8011-h14.