Analysis of Button Bit Wear and Performance of Down-The-Hole Hammer Drill

This work investigates bit button wear and performance of Down-The Hole Hammer (DTH) drill in Navachab Gold Mine, Namibia. Rock samples obtained were tested in the laboratory for chemical composition, equivalent quartz content and compressive strength. Schmidt hammer was used to determine the rebound hardness values of the selected rocks. The specific energy was determined by using empirical equation. The length of insert buttons on the surface of the drill bits were measured by using digital vernier caliper at regular intervals as drilling operation progressed and wear rates were correlated with the rock properties. Silica content varied from 71.34 – 71.83% and 83.25 – 83.56% for oxidised and non-oxidised schist respectively. The equivalent quartz content was estimated to 72.30% for oxidised schist and 64.20% for non-oxidised schist. The highest wear rate was experienced on the non-oxidised schist having equivalent quartz content of 72.30%. This revealed that wear of rock drill bit is influenced by rock properties. Uniaxial compressive strength varied from 123 to 194 MPa. The strength characteristics of these rocks varied from medium to high strength. Rebound hardness values from the LType schmidt hammer ranged from 42 to 58 for oxidised and non-oxidised schist. Rebound hardness values obtained from N-Type schmidt hammer varied from 50 to 58 for oxidised and non oxidised schist. The specific energy varied from 6.0 MJ/m3 for oxidised schist to 12.5 MJ/m3 for non-oxidised schist. Moreso, wear rate varied from 0.0284 - 0.1045 mm/m for oxidised and non oxidised schist respectively. The result of correlation matrix revealed that uniaxial compressive strength, equivalent quartz content and silica content are dominant rock properties affecting wear rate of bit button of DTH drill.Keywords: Wear, Button, Down-The-Hole, Drill, Performanc

Recognising the Key Role of Agriculture In Achieving Sustainable Development Goal 2: Challenges And Prospects In Nigeria

The issue of food security has in recent times attracted a lot of scholarly debates in Nigeria. In spite of different methodologies utilised by the governments in addressing the challenge, the issue still persists. Results further revealed that the agricultural sector has not performed palatably in its quest for ensuring sustainable development. Suffice to note that agriculture should be given its rightful place if the country wants to experience development that will be said to be sustainable. In addressing this, the second Sustainable Development Goals (SDGs) become handy because of its emphasis on eradicating hunger, which can only be achieved when the role of agriculture is recognised in the nation. It is on this premise that this paper examined the key role of Agriculture in achieving Sustainable Development Goal 2 in Nigeria. This is a conceptual paper that relies on an extensive review of related literature. The findings show that the agriculture sector faces many challenges, making it quite difficult in achieving its main goal which is ensuring an adequate supply of food in all parts of the country. In specificterms, the current insurgency in Northern Nigeria has been one of the major factors which have further destabilised the lopsided agricultural sector in the country. The paper recommended among others that investment in the agricultural sector should be given top priority by the Federal, State and Local Governments so that the continuous dependence on imported products will be reduced, as well as to relieve dependence on the oil sector for economic growth

IN VIVO AND IN VITRO EFFECTS OF ARTEMISININ GROUP OF DRUGS ON TRYPANOSOMOSIS IN MICE

This study was done to study the effect of artemisinin groups of drugs on mice experimentally infected with the protozoan Trypanosoma brucei and on Trypanosoma brucei invitro. Commercial artesunate and artemether were used with diminazene aceturate serving as control. It was discovered that artemether administration resulted into seven days of aparasitaemia of trypanosomosis in vivo and reduced motility of the trypanosomes in vitro. There was synergistic effect in the action of artesunate and diminazene aceturate. In vitro analysis gave a similar result in that the trypanosome were found to be sensitive to artemether  with an MIC of 0.6µl,  artesunate with berenil combination and the artemether treatment group 2.5µM. The implication of these results is discussed and advice is given on the potential adaptation of artesunate for treatment of trypanosomosis and planting of Artemisia annua tree in the country.Â

The Effect of Temperature on Nutrient Removal from Wastewater by Selected Fungal Species

The main goal of wastewater treatment is to safeguard the environment by preventing the pollution of receiving water bodies. This study was aimed at investigating the effect of temperature in nutrient removal by four test fungal species (Fusarium sp, Absidia sp, Aspergillus niger and Aspergillus flavus) in synthetic wastewater at different incubation temperatures of 25oC, 30oC, 35oC and 40°C. After inoculation with each test isolate, aliquot samples were taken prior inoculation and every 24 h, for 96 h for the estimation of phosphate, nitrate and pH in the wastewater, using standard procedures. After 96 h incubation, the percentage phosphate concentration removal ranged between 29.17 %-36.17 %, 26.17 %-35.75 %, 8.01 %-37.94 % and 11.19 %-42.65 %, in the presence of the Fusarium sp, Absidia sp, Aspergillus niger and Aspergillus flavus, respectively. Optimum temperature for phosphate removal was observed at 30°C -40°C. After 96 h incubation at 25oC, the phosphate concentration was very high with most of the isolates. In the case of nitrate, highest removals of 42.89 % and 82.07 % were obtained at 35°C in the presence of the Fusarium sp and Aspergillus flavus. In the presence of the Absidia sp and the Aspergillus niger, maximum removals of 21.21 % and 30.59 %, respectively were observed at 25°C, after 96 h incubation. The study was revealed the effect of temperature in the removal of phosphate and nitrate from wastewater by the test fungal species

Development of Longitudinal Split Failure in White-Rotted Aspen (Populus Tremuloides Michx.)

Longitudinal splits and associated smooth fracture planes were often noted along the growth ring boundaries of aspen, Populus tremuloides Michx., which were impact-loaded on the tangential plane, after decay by Trametes versicolor (L.: Fr.) Pilat, and Bjerkandera adusta (Willd.: Fr.) Karst. To characterize this failure pattern, scanning (SEM) and transmission (TEM) electron microscopy were employed. Results showed that this failure is a result of longitudinal fracture lines that cut through the parenchyma cell-wall layers (transwall failure) and opened the lumens. These parenchyma cells were preferentially invaded by fungal hyphae early (weight loss = 10%) in the degradation process. Prominent on the fracture planes was evidence of parenchyma cross walls perpendicular to the fiber axis, fungal hyphae, and associated hyphal sheaths. Localized fracturing along the parenchyma cells suggests that fungal invasion and degradation patterns influence the development and morphology of longitudinal fracture in wood

Present state of research on narrow wheels: a prerequisite for traction studies on non-lug narrow wheels

The use of narrow wheels as traction members of simple agricultural machinery and equipment has been investigated. This equipment can be easily acquired and maintained by low income earners and the rural dwellers whose occupation is predominantly farming. The off road performance of these narrow wheels in terms of rolling resistance, coefficient of rolling resistance, and the net traction ratio as they affect the tractive efficiency are discussed. The various factors such as the wheel diameter, inflation pressure, axle load and the operating speed on different soil conditions as they affect the off road performance are also highlighted. The size of the wheel and its weight is a good measure to combat the negative effects of soil compaction on agricultural soils. Existing models describing the tractive performance of agricultural wheels are stated and analyzed and the generalization of such models for predicting the tractive performance is discouraged

Socioeconomic effects of Oyo state government COVID-19 palliatives on tomato smallholder farmers

Open Access ArticleThis study interviewed 197 farmers that benefitted from the government palliative in the form of tomato farm inputs to help farmers contain the negative effects of COVID-19 of hunger, food insecurity, and poverty. Demographic features show that the average family size was 6, average age of the beneficiaries was 43, gender of the household heads shows that the beneficiaries have 67% males and 33% females. Production features show that 28% of the tomato farmers intercropped their tomato with other crops, 40% of them went through government training, and 25% of them accessed credit to take of their farms. Farmer to farmer was the main source of information (77%). Using the Likert Scale characterization shows that 74.6% of the farmers believed that the palliative increased their yield, 81.2% agreed that the palliatives just reduced hunger in their household, while 86.3% agreed that there was an increase in their farm income as a result of the intervention. Logit regression results reveal that Farmer’s Age, Farm Income, Loan Access, and Tomato Yield are the factors that significantly increased perception of tomato farmers on hunger reduction. Farm Income and Loan Access factors have a positive coefficient which is significant at the 1% level, while Farmer’s Age and Tomato Yield have positive coefficients but is significant at the 5% level. Association Membership negatively and significantly reduced farmers’ perception of hunger reduction at the 5% level of probability while farmer-to-farmer information sources significantly reduced it at a 1% level of probability; meaning that only government extension agents and the media positively influenced information transfer on the government palliative efforts. The study recommends that government assistance should be extended to other resource-poor farmers and that getting access to loans should be made easier for farmers by the government

Assessment of Biophilic Design Patterns on Skill Development, In Minna, Niger State

As an interactive sustainable alternative to existing sustainable design practices, biophilic design struggles to promote the possibility of merging the built and natural environment. The study is aimed at assessing the extent to which biophilic design patterns influences skill development in order to suggest interactive sustainable alternatives. The study adopted a mixed method of research. Qualitative data were obtained via the review of relevant literature while quantitative data were obtained via the use of a structured questionnaire administered to 32 respondents in the study population. The respondents were selected from the users of purposebuilt skill acquisition and development spaces in Minna, Niger state, to determine the level of satisfaction with the implementation of these patterns and considerations in skill acquisition and development space. The quantitative data was analysed with the use of statistical package for social sciences (SPSS) and the results presented descriptively with the use of tables. The findings suggest that most users were satisfied with patterns from nature in space patterns and natural analogue patterns relating to direct and indirect connection with natural system

MODELING THE PERFORMANCE OF A BAOBAB SEED DECORTICATOR USING RESPONSE SURFACE METHODOLOGY

Decortication of baobab seed manually after soaking or roasting is time consuming, labour-intensive and uneconomical. The demand for baobab kernel as a source of protein is increasing for use as supplement for animal protein ration, for edible oil consumption and for other industrial uses. To ameliorate this problem, a baobab seed decorticator has been developed. This study therefore focused on the effects of process parameters; moisture content of seed, speed of decorticator and concave-shaft clearance on percentage clean kernel (Pck), percentage broken kernel (Pbk), percentage whole seed (Pws) and decorticating efficiency (DE), using Response Surface Methodology (RSM). In designing the experiments, Box-Behnken Design (BBD) was selected. Analysis of Variance (ANOVA) was carried out to evaluate and select the appropriate dependent (Pck Pbk, Pws and DE) and independent variables using both the F and P-values calculated at 95% confidence level (a=0.05). Mathematical models relating the process parameters to the responses were developed. The developed models were validated by comparing the predicted and actual experimental values. The selected quadratic models were adequate for predicting the performance of the developed decorticator. It was observed that a decrease in percentage clean kernel recovery would result if concave-shaft clearance and moisture content were increased. Likewise, the concave-shaft clearance had the highest positive effect while moisture content had the highest negative effect on percentage of broken kernel. All the three factors (process parameters) had positive effects on decorticating efficiency