History of Corruption and National Development: The Case of Nigeria

Nigeria, with a population of over 140 million people, is the most populous country: in Africa: one in five Sub-Saharan Africans is a Nigerian. The country is also rich in both human and natural resources. Billions of dollars were generated yearly from the sale of crude oil and vet nothing to show for this huge revenue in terms of infrastructural development and the living standards of Nigerians. This state of affairs has been attributed to the prevalence of corruption. This paper examines phenomenon called corruption. It discusses the causes and impacts. The paper attributed the causes of corruption in Nigeria to socio-cultural and the political and economic situation of the country. The paper contends that corruption has been responsible for the instability of successive Nigerian administration since independence to date. Besides, it creates negative image and loss of much needed revenue for developmental purposes: it devalues the quality of human life: robs educational and health sectors of revenues; it slows down administrative processes thereby making the execution of government policies to be ineffective. The paper recommends among others, enlightenment of the citizen on the danger of excessive materialism and the culture of “get rich quick”. Besides, the property of any corrupt official should be confiscated and should also be imprisoned for life to serve as a deterrent to others. Keywords: Corruption, Development, Kleptocracy, Prebendalisr

On the gas permeability of the microporous layer used in polymer electrolyte fuel cells

In an attempt to obtain accurate values of the gas permeability of the microporous layer (MPL), substrates with negligible MPL penetration and of known gas permeability, i.e. membrane filters, have been employed. The values of the MPL permeability obtained using the membrane filters were compared with those obtained conventionally using the carbon substrates. Due to MPL penetration, the MPL permeability obtained using the carbon substrate were found to decrease with carbon loading. On the other, due to negligible penetration, the MPL permeability obtained using the membrane filters were found to be almost invariant with the carbon loadings. Furthermore, the MPL permeability was found to be sensitive to the substrate used: more cracks (and subsequently substantially higher permeability) were shown by the MPLs coating the carbon substrates. This implies that the MPLs coating the carbon substrates and the MPLs coating the membrane filters are structure-wise different. It subsequently means that the MPL permeability obtained using the membrane filters cannot be used to estimate the MPL penetration into the carbon substrates

Simultaneous thermal and visual imaging of liquid water of the PEM fuel cell flow channels

Water flooding and membrane dry-out are two major issues that could be very detrimental to the performance and/or durability of the proton exchange membrane (PEM) fuel cells. The above two phenomena are well-related to the distributions of and the interaction between the water saturation and temperature within the membrane electrode assembly (MEA). To obtain further insights into the relation between water saturation and temperature, the distributions of liquid water and temperature within a transparent PEM fuel cell have been imaged using high-resolution digital and thermal cameras. A parametric study, in which the air flow rate has been incrementally changed, has been conducted to explore the viability of the proposed experimental procedure to correlate the relation between the distribution of liquid water and temperature along the MEA of the fuel cell. The results have shown that, for the investigated fuel cell, more liquid water and more uniform temperature distribution along MEA at the cathode side are obtained as the air flow rate decreases. Further, the fuel cell performance was found to increase with decreasing air flow rate. All the above results have been discussed

The effects of the composition of microporous layers on the permeability of gas diffusion layers used in polymer electrolyte fuel cells

The effects of the composition of the microporous layer (MPL) on the through-plane permeability of the gas diffusion layers (GDLs) used in polymer electrolyte fuel cells (PEFCs) have been thoroughly experimentally investigated in this paper. For a given PTFE loading in the MPL, the GDL permeability was found to decrease with increasing carbon loading and this is due to the increase in the thickness of the MPL. For all the investigated carbon loadings of the MPL, the permeability values of the GDLs were found to have common trends for the PTFE loadings ranging from 10 to 50% (by weight): the GDL permeability increases when the PTFE loading in the MPL is increased from 20 to 50%; the GDL permeability decreases when the PTFE loading in the MPL is increased from 10 to 20%; and the GDL permeability is a minimum at 20% PTFE loading present in the MPL. On the other hand, the permeability of the GDL was found to depend on the carbon loading of the MPL in the PTFE range 0–10%. The effects of the MPL composition on the MPL permeability were found to be similar to those on the GDL permeability. However, the permeability values of the MPLs of the same composition, which were supposed to be ideally the same, were found to significantly vary. This was attributed to the MPL penetration into the body of the carbon substrates

Effects of compression on mechanical integrity, gas permeability and thermal stability of gas diffusion layers with/without sealing gaskets

The compressibility, the gas permeability and the thermal stability of 4 commercially available uncoated GDLs (or carbon substrates) and MPL-coated GDLs are, with/without Teflon and silicone sealing gaskets, investigated before and after performing ex-situ compression tests mimicking the compressive stresses within the fuel cell. The results show that the gas permeability of the tested GDLs are impacted more with Teflon gaskets than with the silicone gaskets and this is due to the lower stiffness of the former gaskets. Likewise, the GDLs are more deformed with the Teflon gaskets than with silicone gaskets and this is due to the same reason mentioned above. The thermogravimetric analysis (TGA) data suggests that the bare carbon substrates, unlike the MPL-coated GDLs, lose up to 40% of the PTFE material after the compression test either with or without sealing gaskets

Musculoskeletal pain among postmenopausal women in Nigeria: Association with overall and central obesity

Background: Menopausal women experience musculoskeletal changes such as muscle atrophy, muscle weakness and osteoporosis—symptoms associated with advancing age coupled with depletion of the female sex hormone, estrogen. Estrogen is important in the maintenance of the integrity of the musculoskeletal system and its reduction in the circulation due to menopausal transition results in reduced resting metabolic rate, lowered energy expenditure, increase in fat mass, and central adipose tissue accumulation. Objective: This study investigated the prevalence of musculoskeletal pain (MSP) in postmenopausal women (PMW) in Nigeria. We examined the association of overall and central obesity with complaints of MSP and the screening potential of obesity measures for risk of musculoskeletal problems among PMW in Nigeria. Methods: This was a cross-sectional survey of MSP in 310 PMW in Ibadan, Nigeria. MSP was assessed using the Standardized Nordic Musculoskeletal Questionnaire, and overall and central obesity were assessed using body mass index (BMI), waist/height ratio (WHtR), waist circumference, and waist/hip ratio. Data were analysed using descriptive statistics, chi-square test, and logistic regression models with the probability level at p = 0.05. Results: Participants were of the modal age group (51–60 years). The highest prevalence rates of MSP were in the lower extremity (189; 61.0%) and the back (164; 52.9%). A direct association was observed between the categories of BMI and lower extremity symptoms (p < 0.05), and the categories of WHtR and waist circumference were associated with back and lower extremity symptoms (p < 0.05). Postmenopausal women had greater odds of reporting MSP across various classes of BMI. WHtR revealed the greatest odds for back (odds ratio = 1.70, 95% confidence interval 1.07–2.75) and lower extremity symptoms (odds ratio = 2.33, 95% confidence interval 1.44–3.78). Conclusion: Lower extremity and back pain symptoms were the most prevalent. For overall and central obesity directly associated with MSP, WHtR seemed the best obesity screening tool for MSP in postmenopausal women

Through-plane gas permeability of gas diffusion layers and microporous layer: Effects of carbon loading and sintering

© 2017 Energy Institute.Knowledge of the absolute permeability for the various porous layers is necessary to obtain accurate profiles for water saturation within the membrane electrode assembly (MEA) in a two-phase model of a polymer electrolyte membrane fuel cell (PEMFC). In this paper, the gas permeability of gas diffusion layers (GDLs) coated with microporous layers (MPLs) of various carbon loadings for two different carbon blacks have been experimentally measured. The permeability of the GDL was found to decrease by at least one order of magnitude after the MPL-coating. Also, the permeability of the MPLs was shown to be lower than that of the carbon substrate by 2-3 orders of magnitude. Further, it was found that the gas permeability of the MPLs changes significantly from one carbon loading to another despite the use of a single weight composition for all the MPLs coated, namely 20% PTFE and 80% carbon black. This signifies the possible inaccuracy in estimating the MPL permeability through employing the cross-section SEM images as they do not resolve the MPL penetration into the carbon substrate. Finally, the MPL sintering was found to slightly decrease the permeability of the GDL

Investigating fuel-cell transport limitations using hydrogen limiting current

Reducing mass-transport losses in polymer-electrolyte fuel cells (PEFCs) is essential to increase their power density and reduce overall stack cost. At the same time, cost also motivates the reduction in expensive precious-metal catalysts, which results in higher local transport losses in the catalyst layers. In this paper, we use a hydrogen-pump limiting-current setup to explore the gas-phase transport losses through PEFC catalyst layers and various gas-diffusion and microporous layers. It is shown that the effective diffusivity in the gas-diffusion layers is a strong function of liquid saturation. In addition, it is shown how the catalyst layer unexpectedly contributes significantly to the overall measured transport resistance. This is especially true for low catalyst loadings. It is also shown how the various losses can be separated into different mechanisms including diffusional processes and mass-dependent and independent ones, where the data suggests that a large part of the transport resistance in catalyst layers cannot be attributed to a gas-phase diffusional process. The technique is promising for deconvoluting transport losses in PEFCs