Matrix Method of Determining Optical Energy Bandgap of Natural Dye Extracts

In this paper, a total of fourteen dye extracts from different plants’ parts (flowers and fruits) were extracted. Absorbance of light by dye extracts with 5%, 10% and 20%concentrationsweremeasured using a UV-Vis spectrophotometer at different wavelengths. A system of linear equations in terms of wavelength and absorbance without film thickness was developed and solved using MATLAB software. Also, optical energy bandgap (Eg) obtained experimentally are at range of 1.77- 2.76 eV. From the solutions of the system of equations, the (Eg) of the natural dyes were obtained. The results show all the dye extracts have (Eg) in the range 1.34-2.09 eV which falls within the range of UV and IR portions of the electromagnetic spectrum. Also, the results reveal that sunflower (Helianthus) dye has the smallest (Eg) of 1.34 eV and guava (Guajava) peel dye with the higher (Eg) of 2.09 eV. This means Helianthus dye absorbs more light over a wider part of the electromagnetic spectrum and the easier electron transfer from its valence band to the conduction band. The values obtained via matrix method are in agreement with the experimental values with slight deviation, hence this validates the matrix method of obtaining optical energy bandgaps

Strategy to Select and Grade Efficient Dyes for Enhanced Photo-Absorption

In this paper, a simple strategy to select and grade efficient natural dye-sensitizers for photo-absorption is developed. The selection criteria help to choose efficient dye for construction of solar cell. On the other hand, the dye-grade technique based on light and matter interaction parameters (absorbance, anthocyanin, and light harvesting efficiency) further reduce the number of dyes for efficient dye-sensitized solar cell (DSSC) production. The result shows that the dyes extracted from witch seed flower (Striga hermonthica), flamboyant flower (Delonix regia), and bitter gourd (Momordica charantia) have dye-grade 1, are the most efficient photo-absorber for enhanced DSSC fabrication while guava peel dye has grade 10 being the least efficient dye. The selection criteria and dye-grade techniques provide surer way of getting promising dyes for effiective DSSC production than choosing the dyes randomly based on some features like their colors and abundance

Performance Evaluation of Power Tiller in Bauchi State Nigeria

The research work involves performance evaluation of Power Tiller in the Savanna agro-ecological zone of Nigeria. Bauchi State Agricultural Development Programme’s farm was used as the study area having satisfied the condition for a small scale farm in a developing economy. The Power Tiller speeds was measured using stopwatch and a measuring tape, width of cut of the machine was measured using measuring tape, soil moisture content was obtained using a laboratory oven drier and the depth of cultivation and fuel consumption was measured using a graduated dip stick. The results obtained were from the following field parameters: effective field capacity, field efficiency, fuel consumption, speeds of operation, depth and width of cut. These parameters were determined from field work and laboratory experiment and the basic operations considered during the field operations were ploughing and rototilling. The field efficiency obtained was 47 and 48 percent for ploughing and rotovating with effective field capacity of 0.04ha/hr. and 0.06ha/hr. respectively. The fuel consumption was 1.3L/hr. and 1.6L/hr. for ploughing and rotovating at a depth of 9cm and 5.5cm when the soil moisture contents were 6.3 and 8 percent respectively. The result shows that the machine is suitable for small scale farmers in Savanna Agro-ecological zone. Keywords: Power Tiller, Performance Evaluation, Effective Field Capacity, Field Efficienc

The Impact of Health Expenditure on Maternal and Child Mortality in African Countries

he world has experienced a decline in maternal and child mortality in the last few decades, increase in global health expenditure over the years was the major factor responsible for that. But in Africa and other developing countries, the rate of maternal and child mortality has been soaring. The objective of this paper is to investigate the impact of health expenditure on maternal and child mortality in African countries at different income level. On this note, the paper was based on the panel data covering the period of 2000 to 2017 for 39 African countries. After a cross sectional dependence test and panel unit root test, fixed effect results showed that, government health expenditure has no significant impact on reducing child mortality in African countries at all income level. Whereas, it has an impact on reducing the maternal mortality in low-income and lower middle income countries. It was also found that Private health expenditure has significant impact on reducing child and maternal mortality at all income level. Based on this, the paper recommends that governments at different level especially from low-income and lower middle income countries should provide quality health care services and regular immunization for women and children in order to reduce maternal and child mortality in Africa region

Sero Survey of Foot and Mouth Disease Virus Infection in Cattle Crossing Some Major Border States in Northwestern Nigeria

Foot and mouth disease (FMD) poses a major constraint to international trade in animals and animal products in sub-Saharan Africa. A retrospective and serological survey was conducted in two major Border States of Sokoto and Kebbi in north-western Nigeria. This study was aimed at determining the sero-prevalence of FMD virus (FMDV) antibodies in cattle at international animal control posts and to examine cattle population movement across the border area for a period of one year (January to December 2014) from the available records. Eight hundred and eighty (880) sera samples were collected and screened for the presence of antibodies to FMDV using the competitive enzyme linked immunosorbent assay (ELISA) technique. The data were subjected to chi-square and relative risk to check for independence and association. An overall seropositive rate was found to be 55.2 % (486/880). A 79.9 % (359/450) sero-positive rate was obtained from the Kamba border, while 29.5 % (127/430) was found at the Illela border. Kamba showed a statistically significant (P < 0.05) higher sero-prevalence when compared with cattle that are crossing the Illela border (Relative Risk 2.70; 95 % Confidence Interval 2.317—3.149). Retrospective data from the control posts revealed that an average number of 2019 and 2747 of cattle, respectively, crossed the Kamba and Illela international borders monthly. The highest influx of animals from the Niger Republic through the Illela international border was encountered between the month of March and April 2014. The magnitude of the presence of FMDV Non-structural protein (NSP) antibodies in the study areas is an indication of the infection and the presence of the virus in the study areas and the neighbouring countries