517 research outputs found
Acid Failure of Mild Steel in 2 M Sulphuric Acid in the Presence of Vernonia amygdalina
The degradation of mild steel in 2 M sulphuric acid solution in the presence of Vernonia amygdalina extract
was investigated using gasometric technique. Mild steel coupons of dimension 4 cm by 1.5 cm were
immersed in test solutions of uninhibited acid and also those containing extract concentrations of 60,100
and 140 cm3 at a temperature of 333K for 60 minutes. The volumes of hydrogen gas evolved from the
reaction were recorded and examined. The results showed that while extract concentration was increasing,
H2 evolution and % I.E increased, with a reduction in corrosion rate. The reduction in corrosion rate was
observed to follow in order of increasing extract concentration. Also, phytoconstituent-metal interaction
mechanism was best explained by Freundlich isotherm, with the 4 minutes curve becoming the best contact
time for the extract phytochemicals to properly adsorb to metal surface across all concentrations used.
Furthermore, an expression suitable for estimating corrosion rate values once concentration is known was
also obtained. The microstructural studies however, revealed that increasing the extract concentration led to
considerable reduction in the dominant coarsening of the oxide of iron phase, while the pearlite and ferrite
phases were highly dispersed
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European industrial energy intensity: innovation, environmental regulation, and price effects
We investigate the direct role of technological innovation and other factors influencing industrial energy intensity across 17 EU countries over 1995–2009. We develop an innovative industry-level patent dataset and find compelling evidence that patent stock negatively influences industrial energy intensity. In particular, we find a much stronger effect of patent stock on energy-intensive industries with an estimated coefficient of -0.138 which almost double that of less energy-intensive industries (estimated at -0.085). While our results show that energy price remains the major determinant of energy intensity, the chemicals industry, which is not covered by the EU Emissions Trading Scheme (ETS) during the sample period, appears more susceptible to energy prices relative to other energy-intensive industries that are covered by the EU ETS. Exploring regional differences in carbon taxation, we find a significant decline in energy intensity in Northern Europe owing to the carbon tax policy implemented in the early 1990s across the Nordic countries.EPSRC EP/N024567/
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European Industrial Energy Intensity: The Role of Innovation 1995-2009
We investigate the direct role of technological innovation and other influencing factors on industry-level energy intensity based on a sample of 12 industries across 17 EU countries over 1995–2009. We develop an innovative industry-level patent dataset and find compelling evidence that patent stock negatively influences industrial energy intensity. Using a fixed effects estimator, we find a much stronger effect on energy-intensive industries with an estimated coefficient of -0.138 almost double that of less energy-intensive industries (estimated at -0.085). While our results show energy price remains the major determinant of energy intensity, the chemicals industry appears to be more susceptible to energy prices relative to other energy-intensive industries that are covered by the EU Emissions Trading Scheme (ETS). Our study reveals that asymmetric response of energy intensity to energy prices in which price rises between 2004 and 2008 accounts for more change in efficiency than when prices fall. We also explore regional differences, notably that carbon tax policy in Northern European countries, which began in the early 1990s, is responsible for a significant fraction of the decline in energy intensity in Northern Europe
Environment Induced Failure of Mild Steel in 2 M Sulphuric Acid Using Chromolaena odorata
Failure investigation of mild steel sample in 2 M sulphuric acid solution in the presence of Chromolaena odorata extract was conducted using the gasometric method. Mild steel coupons, each measuring 4 cm by 1.5 cm were completely immersed in test solutions of free acid and also those containing extract quantities of 60, 100 and 140 cm3 at a temperature of 333K for 60 minutes. The volumes of hydrogen gas evolved from the experiment were recorded and analyzed. The result showed that maximum inhibitor efficiency which has a relationship with lowest corrosion rate was obtained at the highest inhibitor concentration of 140 cm3, with reduction in the corrosion rate observed to follow in order of increasing extract volume. Temkin isotherm best described the metal surface interaction adsorption mechanism. Once concentration of the acid is known, an expression for estimating corrosion rate values in the presence of the extract was obtained. Also, the photomicrograph study showed a direct relationship between the extract quantity and the extent of corrosion. Sample immersed in the 140 cm3 extract quantity showed no trace of the third phase but rather the presence of a finely distributed pearlite phase indicating that increased inhibitor concentration led to a reduction in the deterioration of the metal
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State-Level Electricity Generation Efficiency: Do Restructuring and Regulatory Institutions Matter in the US?
This paper examines the impact of deregulation and the political support for it on the electric power industry using a consistent state-level electricity generation dataset for the US contiguous states from 1997-2014. Recent analyses of productivity growth suggests that institutional factors are important and we wish to study the role of deregulation as a statelevel institutional change through two measures: (a) restructuring and (b) the political support for it, measured by the majority political affiliation of public utility commissions. We find evidence of positive impacts of deregulation (both restructuring and the political support for it) on technical efficiency across the models estimated. Our preferred model which allows for the control for deregulation variables on the mean and variance of the inefficiency shows an average technical efficiency of 73.1 percent. The results of the marginal effects reveal that the impact of deregulation including its political support on inefficiency is negative and monotonic, with the potential reduction of 8.4 percent in the mean of technical inefficiency, thereby suggesting a compelling evidence for generation efficiency improvement via deregulation
Microbial evaluation and public health implications of urine as alternative therapy in clinical pediatric cases: health implication of urine therapy
BACKGROUND: Cultural means of pediatric treatment during ill health is a mainstay in Africa, and though urine has been known to contain enteric pathogens, urine therapy is still culturally applicable in some health conditions and also advocated as alternative therapy. The study therefore, is to evaluate the microbial contents and safety of urine. METHODS: Urinary bacteria from cows and healthy children aged 5-11 years were identified by conventional phenotypic methods and antimicrobial susceptibility testing was performed using modified agar disc and well-diffusion methods. RESULTS: A total of 116 bacterial isolates (n = 77 children; n = 39 cows) were identified as Bacillus (10.4%; 5.1%)), Staphylococcus (2.6%; 2.6%), Citrobacter (3.9%; 12.8%), Escherichia coli (36.4%; 23.1%), Klebsiella (7.8%; 12.8%), Proteus (18.2%; 23.1%), Pseudomonas (9.1%; 2.6%), Salmonella (3.9%; 5.1%) and Shigella (7.8%; 12.8%) spp. Antibiotic
resistance rates of the Gram-positive bacteria were high (50.0-100%), except in Bacillus strains against chloramphenicol, gentamicin and tetracycline (14.3%), while higher resistance rates were recorded among
the Gram-negative bacteria except in Citrobacter (0.0%) and Proteus (8.5%) spp. against gentamicin and
tetracycline respectively. The Gram-negative bacteria from ito malu (cow urine) were more resistant bacteria except in Citrobacter (20.0%) and Shigella spp. (0.0%) against tetracycline and Proteus spp. (11.1%), (22.2%) against amoxicillin and tetracycline respectively. Multiple antibiotic resistance (MAR) rates recorded in children urinal bacterial species were 37.5-100% (Gram-positive) and 12.5-100% (Gramnegative), while MAR among the cow urinal bacteria was 12.5-75.0% (Gram-positive) and 25.0-100%
(Gram-negative). Similar higher resistance rates were also recorded among the Gram-negative bacterial species from urine specimens against the paediatric antibiotic suspensions. CONCLUSION: The study reported presence of multiple antibiotic-resistant indicator bacteria in human urine and ito malu used as alternative remedy in pediatric health conditions like febrile convulsio
Cost efficiency and electricity market structure: A case study of OECD countries
The OECD electricity sector has witnessed significant institutional restructuring over the past three decades. As a consequence, many power generation utilities now act as unregulated companies that technically compete to sell power on an open market. This paper analyses the performance in term of cost efficiency for electricity generation in OECD power sector while accounting for the impact of electricity market structures. We employ the short-run cost function in which capital stock is treated as a quasi-fixed factor input. Empirical models are developed for the cost function as a translog form and analysed using panel data of 25 countries during the period 1980 to 2009. We show that it is necessary to model latent country-specific heterogeneity in addition to time-varying inefficiency. The estimated economies of scale are adjusted to take account of the importance of the quasi-fixed capital input in determining cost behaviour, and long run constant returns to scale are verified for the OECD generation sector. The research findings suggest there is a significant impact of electricity market regulatory indicators on cost. In particular, public ownership and vertical integration are found to have significant and sizable increasing impacts on cost, thereby indicating policy lessons on the desirable ways to implement structural electricity generation reforms
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Incentive Regulation, Productivity Growth and Environmental Effects: The Case of Electricity Networks in Great Britain
We analyse the productivity growth of electricity transmission and distribution networks in Great Britain and how changes in incentive mechanism have influenced the measured total factor productivity (TFP). In doing so we are also concerned to examine the effects of quality of service and environmental targets on measured productivity growth. It is increasingly important that productivity measures adjust for the increasing regulatory pressure to reduce the wider societal impacts of the electricity sector and improve quality of service. Failure to do so, may mean that productivity growth may look slower than it actually is. We employ a DEA technique which considers the underlying data without a stochastic element. Our findings show that productivity growth is consistently low for the period we examine, in the region of 1% p.a. over the 29 years from 1990/1991-2018/2019. For both electricity transmission and electricity distribution we try to monetise a wider range of quality and emissions variables in order to show the difference their inclusion makes to measured productivity growth. We show that it can make a difference both positively and negatively, though often this difference is small (e.g. 0.1% p.a.). However, the impact can be much larger (c. 1% p.a.), especially with respect to improvements in quality of service in the distribution network. In the context of generally slow productivity growth, we therefore show the importance of appropriate measurement
The Business Case for Community Paramedicine: Lessons from Commonwealth Care Alliance's Pilot Program
Mobile integrated health care and community paramedicine (MIH-CP) programs expand the role of traditional emergency medical services personnel to address non-emergency needs and bring outpatient primary and urgent care into patients' homes. These programs offer potential for reducing health care costs, eliminating unecessary emergency department use, and shifting service back to community-based and home settings. Between 2014 and 2015, the Massachusetts-based Commonwealth Care Alliance (CCA) piloted a community paramedicine prgoram, Acute Community Care (ACC), to serve its members in the Greater Boston area.This brief summarizes ACC's business case assessment, which showed that increasing patient volume after the pilot period would reuslt in net savings given the progam's success in averting unnecessary emergency care. By illustrating cost considerations for an expansion of MIH-CP services, this brief may inform the design and sustainability planning of other MIH-CP programs. The business case assessment was conducted by Mathematica Policy Research through support from the Center for Health Care Strategies' Complex Care Innovation Lab, a Kaiser Permanente Community Benefit-funded initiative
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