Influence of Plating Parameter and Surface Morphology on Mild Steel

The plating parameter effect of zinc deposition on mild steel substrates was investigated. The results showed an improved surface finished and homogeneous layer. The distance between the anode and the cathode on voltage, plating time and coating thickness were considered. The mild steel was deposited into solution of zinc bath for varying voltage between 0.5 v and 1.0v. It was discovered that the sample plated at 0.8v for 15 minutes gives the best plating deposition and appearance. The surface morphology of the plated sample was analyzed by Focused ion beam scanning electron microscopy (FIB-SEM), AFM and X-ray diffraction

Antibacterial Susceptibility and Resistance Pattern of Organisms Isolated from Rectal Swab of Chicken

Resistance to antibiotics is a serious matter of concern for Public and threats to the successful treatment of miscrobial disease. The prevalence of some enterobacteriaceae such as Escherichia coli and Salmonella spp resistant to antimicrobial agents is increasing. This study is intended to determine susceptibility and resistance pattern of pathogenic isolates from the rectal swabs of chicken to 8 antibiotics. Hundred (100) rectal swabs of chickens were collected randomly from three different farms; a farm at Montan, Awotan, Apete and Apata all in Ibadan Metropolis of Oyo State. Isolation and identification of organisms were done using standard bacteriological techniques. Antimicrobial susceptibility test was performed following standard protocol. A total of 93 bacterial isolates were obtained from the hundred (100) rectal swaps of chicken. The isolates Escherichia Coli, Staphylococcus aureus and Salmonella spp. and their percentage of prevalence are 54, 43 and 3. Antibiotic susceptibility tests carried out on the isolates showed that most of the isolates were resistant to ofloxacin, cloxacillin and Augumentin, while almost all the isolates in this study are sensitive to gentamicin. Erythromycin did not have any effect on any of the bacterial isolates. Bacterial isolates obtained in the study area were multi drug resistant and this suggests that the chickens are important reservoir of antimicrobial resistant organism which is a major public health concern

Study of Influence of Zinc Plated Mild Steel Deterioration in Seawater Environment

The corrosion resistance of electrolytic zinc-coating on mild steel in seawater was investigated. Mild steel samples were zinc electroplated at voltage varied (0.6, 0.8, 1.0, 1.5 V) and for plating time also varied (20, 30, 40, 50, 60 minutes). Focused ion-beam scanning electron microscopy was used to observe the surface morphology of the plated surface. The visual observation of plated samples revealed that samples plated at 0.6 V for 20 and 60 minutes; 0.8 V for 30 minutes and 1.0 V for 40 minutes showed the best physical properties such as colour, brightness, fineness, streak and strong adhesion. The plated samples were then subjected to seawater environment for 30 days. The electro-potentials mV (SCE) was measured daily. Weight loss was determined at intervals of five days for the duration of the exposure period. Experimental result showed little corrosion attack on the zinc-plated samples on the fifteenth and twenty-fifth day’s exposure. The severity of attack decreases with increasing weight of zinc coated on substrate. Significant increases in the corrosion resistance were achieved for the plated samples compared with that of the substrate. The pH of the seawater became more alkaline at the end of the thirty days test

STUDY OF THE ELECTROCHEMICAL BEHAVIOR AND SURFACE INTERACTION OF AA6063 TYPE AL-MG-SI ALLOY BY SODIUM MOLYBDATE IN SIMULATED SEA WATER ENVIRONMENT

The potential of sodium molybdate on the corrosion of aluminium alloy AA6063 type was examined with the view to study the electrochemical and surface degradation for metal-inhibitor interface using gravimetric and electrochemical corrosion techniques in simulated s~awater environment. The microstructures of as-corroded samples were also assessed for their surface morphology.The results show thatcorrosion rate decreased with an increase in the inhibitor concentration and exposure time. Equally, the inhibition efticiency increased with inhibitor addition with maximum efficiency obtained at 5g/v sodium molybdate addition. The adsorption of the molecules of the extract on the aluminium alloy surface obeyed the Langmuir adsorption isotherm. The potentiodynamic polarization results showed that sodium molybdate acted as mixed-type i•1hibitor

PERISCOPING THE IMPLEMENTATION CHALLENGES OF NATIONAL POLICY ON EDUCATION IN NIGERIA

This paper sought to identify the implementation challenges of National Policy on Education in Nigeria. Jt argues that there are numerous · challenges impeding the effective implementation of the policy. This paper relies on secondary sources of data and the analysis was done thematically. The significance of this paper rest in the fact that it provides an insight for both policy makers and implementers on the necessary challenges that need to be addressed for the effective implementation of the policy. The paper concludes that it is imperative for policymakers to pay attention to evaluating the education policy, by so doing they will be able to aware of the extent to which they have successfully implemented the policy in line with their pre-determined objectives

Effects of bone particle on the properties and microstructure of polypropylene/bone ash particulate composites

The effects of uncarbonized (fresh) and carbonized bone particles on the microstructure and properties of polypropylene composites have been studied. The addition of the bone particles ranges from 5 to 25 wt% in uncarbonized and carbonized forms in the polypropylene matrix. The physical and mechanical properties were used as criteria for the evaluation of the composites. Microstructures of the composites were assessed with scanning electron microscopy (SEM/EDS). The results revealed that the addition of carbonized bone particles reinforcement has superior properties than uncarbonized bone particles composite based materials with an increase in the compressive strength, hardness values, tensile strength and flexural strength by 53%, 45% and 35% respectively, and a decrease in the % elongation and impact energy by 75% and 32%, respectively at 25 wt% carbonized bone, with 28% increase in tensile strength at 15 wt% carbonized bone addition. The increase in strength and hardness values was attributed to the distribution of hard phases of bone particles in the ductile polypropylene matrix

Chemical interaction, interfacial effect and the microstructural characterization of the induced zinc–aluminum–Solanum tuberosum in chloride solution on mild steel

In this study, we report the effect of Solanum tuberosum (ST) as a strong additive on the morphological interaction, wear, and hardness properties of electroplated zinc coating in chloride bath solutions. The structural and the mechanical behavior of the Zn–Al–ST coating were studied and compared with the properties of Zn coatings. Characterization of the electrodeposited coatings were carried out using scanning electron microscopy, energy dispersive spectrometer, AFM, and X-ray diffraction techniques. The adhesion between the coatings and substrate was examined mechanically using hardness and wear techniques. From the results, amorphous Zn–Al–ST coatings were effectively obtained by electrodeposition using direct current. The coating morphology was revealed to be reliant on the bath composition containing strong leveling additives. From all indications, ST content contribute to a strong interfacial surface effect leading to crack-free and better morphology, good hardness properties, and improved wear resistance due to the precipitation of Zn2Si and Zn7Al2Si3. Hence, addition of ST is beneficial for the structural strengthening, hardness, and wear resistance properties of such coatings

Analysis of the variability of airborne particulate matter with prevailing meteorological conditions across a semi-urban environment using a network of low-cost air quality sensors.

The concentrations of fine and coarse fractions of airborne particulate matter (PM) and meteorological variables (wind speed, wind direction, temperature and relative humidity) were measured at six selected locations in Ile Ife, a prominent university town in Nigeria using a network of low-cost air quality (AQ) sensor units. The objective of the deployment was to collate baseline air quality data and assess the impact of prevailing meteorological conditions on PM concentrations in selected residential communities downwind of an iron smelting facility. The raw data obtained from OPC-N2 of the AQ sensor units was corrected using the RH correction factor developed based k-Kohler theory. This PM (corrected) fast time resolution data (20 s) from the AQ sensor units were used to create daily averages. The overall mean mass concentrations for PM2.5 and PM10 were 213.3, 44.1, 23.8, 27.7, 20.2 and 41.5 μg/m3 and; 439.9, 107.1, 55.0, 72.4, 45.5 and 112.0 μg/m3 for Fasina (Iron-Steel Smelting Factory, ISSF), Modomo, Eleweran, Fire Service, O.A.U. staff quarters and Obafemi Awolowo University Teaching and Research Farm (OAUTRF), respectively. PM concentration and wind speed showed a negative exponential distribution curve with the lowest exponential fit coefficient of determination (R2) values of 0.08 for PM2.5 and 0.03 for PM10 during nighttime periods at Eleweran and Fire service sites, respectively. The relationship between PM concentration and temperature gave a decay curve indicating that higher PM concentrations were observed at lower temperatures. The exponential distribution curve for the relationship between PM concentration and relative humidity (RH) showed that PM concentrations do not vary for RH 80 % for both day and nighttime. The performances of the MLR model were slightly poor and as such not too reliable for predicting the concentration but useful for improving predictive model accuracy when other variables contributing to the variability of PM is considered. The study concluded that the anthropogenic and industrial activities at the smelting factory contribute significantly to the elevated PM mass concentration measured at the study locations

Global occurrence, chemical properties, and ecological impacts of e-wastes (IUPAC technical report)

The waste stream of obsolete electronic equipment grows exponentially, creating a worldwide pollution and resource problem. Electrical and electronic waste (e-waste) comprises a heterogeneous mix of glass, plastics (including flame retardants and other additives), metals (including rare earth elements) and metalloids. The e-waste issue is complex and multi-faceted. In examining the different aspects of e-waste, informal recycling in developing countries has been identified as a primary concern due to widespread illegal shipments, weak environmental as well as health and safety regulations, lack of technology and inadequate waste treatment structure. For example, Nigeria, Ghana, India, Pakistan and China have all been identified as hotspots for the disposal of e-waste. This article presents a critical examination on the chemical nature of e-waste and the resulting environmental impacts on, for example, microbial biodiversity, flora and fauna in e-waste recycling sites around the world. It highlights the different types of risk assessment approaches required when evaluating the ecological impact of e-waste. Additionally, it presents examples of chemistry playing a role in potential solutions. The information presented here will be informative to relevant stakeholders to devise integrated management strategies to tackle this global environmental concern