Thermal properties of TeO2-ZnO-Na2O glasses: effect of Dy2O3 doping

Over the years there has been numerous researches on thermal stability and other thermal parameters of glasses. Among the glasses, tellurite glasses has become more interesting but challenging lately. These properties are essential in unravelling the physical properties of the glasses. But there is not much information on thermal properties of Dysprosium doped zinc sodium tellurite glass, hence the need for this study. Therefore systematic series of quaternary zinc sodium tellurite glasses doped with dysprosium ion in the form (65-x)TeO2-25ZnO-10NaO-xDy2O3 (where x = 0.0, 0.4, 0.8, 1.2, 1.6, and 2.5 mol%) have been successfully prepared via conventional melt quenching technique. X-Ray Diffraction (XRD) pattern was used to confirm the amorphous nature of the glasses, while density (ρ) of the prepared glasses were obtained via Archimedes method. Differential thermal analysis (DTA) curves for the studied glass samples with different Dy2O3 contents have been obtained to determine the glass transition temperature (g), crystallization temperature (Tc), glass stability temperature (ΔTs) Hruby’s parameter (H). From the DTA profile, the glass transition temperature Tg, was in the range of 287-302 °C, crystallization temperature Tc from 408-502 °C, glass melting temperature Tm, 662-659 °C and crystallization onset temperature Tx is estimated to be between 354-389 °C. The thermal stability factor, defined as ΔTs = Tc - Tg, for all the samples are higher than 100 °C while Hruby’s parameter H, is 0.47-1.33. These suggest that the prepared tellurite glass exhibits a good thermal stability and consequently might be a potential candidate for fibre drawing and other nonlinear optical devices.Keywords: Tellurite glass, DTA, Thermal stability & Hruby’s Paramete

Some aspects of fisheries ecology in Thomas dam, Kano Nigeria

The diversity, length-weight relationship and condition factor of fish species of Thomas Dam, Dambatta Kano were studied fortnightly between November, 2016 and February, 2017. Fish species were collected using line nets, cast nets, hooks and traps; weighted to the nearest gram and standard length measured to the nearest centimeter. A total 313 fishes comprising of 7 families and 11 species were identified. Family cichlidae was predominant(36.7%) represented by T. zilli (21.7%) and Oreochromis niloticus (15.0%). Family Claridae was the second highest in abundance with 24.7% represented by C. garipienus (8.9%), Clarias anguillaris (8.9%) and Heterobranchus sp. (6.7) while Protopteridae represented by Protopterus sp. was the least with 2.8%. Species diversity determined by Shannon Weiner index of diversity, Evenness index and Margalef’s index which revealed the highest value at site A of 1.45, 0.78 and 2.66 while site D had the least with 1.1, 0.64 and 1.72 respectively. Growth coefficient b of the length weight relationship ranged from 0.9 to 2.7 inHeterobranchussp. andClariasgariepinus. The b values of the all the fish species is less than the mean exponent b =3, indicating a negative allometric growth. Condition factor (K) for all fish species differed significantly (P<0.05) as the highest value was recorded in Mormyrus rume and Heterobranchus sp. with 1.9 each and the least were C. gariepinus and C. anguillaris, protopterus sp. and Labeo senegalensis each had 0.9 values respectively. The mean condition factor (K) by species was greater than 1, indicating that the fish species were not in good condition.KEY WORDS: Species diversity, Length-weight relationship, Condition factor, Allometric growth, Thomas Dam, Dambatta Kano State

Good Governance and Economic Growth in Africa

African countries face with the problem of good governance and steady economic growth for over period of time. Therefore, the paper aims to examine the good governance and economic growth for the 50 African countries for the period of 2002 to 2020 using the System GMM approach. The data were sourced from the World Development Indicators and World Governance Indicators (2020). The Empirical findings indicated that all the good governance indicators are positive and statistically significant in influencing the level of economic growth in the region, except the government effectiveness which is positive but statistically insignificant. Based on the findings, African countries should provide extensive policies that promote good governance in the region as the region is the backward in terms of good governance compare with other regions in the world. More so, governments in the region should strengthen their political will through transparency and accountability in all aspect of government activities which will reduce the level of political unrest and promote regulatory quality in the region and propel growth

Bioefficacy of ethanolic leaf extracts of some botanicals against cowpea beetle, Callosobruchus maculatus F. [Coleoptera: Chrysomelidae]

No Abstract

Bioethanol Production from Two Varieties (Saccharum Officinarum and Saccharum Barberi) Of Sugarcane Peels

Provision of an alternative clean source of fuel with less cost, will reduce fossil fuel demand. Pollution is the major environmental problem. Air pollution is among the three types of pollution where harmful substances such as CO2 and CO are introduced to the environment and cause harm to humans and animals. Fossil fuel combustion from automobiles and industries causes this type of pollution. There is need to replace another source of fuel with renewable feedstock such as the peels of Saccharum officinarum and Saccharum barberi which are lignocellulose materials to produce bioethanol that has a lower impact on air pollution and the Ozone layer which causes Green-House effect than fossil fuels. Dilute H2SO4 at different concentrations of 1M,2M,3M,4M and 5M were replicated into three different parts respectively as hydrolysing solution. Saccharomyces cerevisiae was used as fermentation enzymes. Different pH values of 5, 6 and 7 was used for fermentation periods of 5, 6 and 7 days, respectively. The Bioethanol was distilled by the use of fractional distillation. Hydrolysed samples of 3M for 6th day of both Saccharum officinarum and Saccharum barberi produced the best yields of bioethanol at the pH of 5 and 5M hydrolysed samples of both Saccharum officinarum and Saccharum barberi produced the least bioethanol for all pH values and fermentation days. The Bioethanol produced was blended with kerosene fuel to create EK10 and EK20 kerosene-bioethanol blends for use as a fuel source in a kerosene lamp. EK10 blend took 126 hours to burn in a rotary kerosene lamp, while EK20 blend took 167 hours to burn-off in the same kerosene lamp. Hydrolysed H2SO4 of 3M, pH 5 and fermentation period of 6 days for both Saccharum officinarum and Saccharum barberi shows the best sample to produce bioethanol. The bioethanol kerosene blend EK10 and E20 was concluded to show long period of burning with clean soot in a rotary kerosene lamp, therefore the bioethanol kerosene blends can be used as substitutes for kerosene fuel