In this paper, the potential capacitance of shea butter (SB) was studied using thermal influenced by varying the temperature between 30°C and 80°C, and distance between the plates from 1 cm to 3 cm. Though different samples were not used for this research, the qualities of various SB in term of physical and chemical composition are related. The SB exhibit dielectric property which satisfies the common law due to short distance effect that is inversely proportional to the amount of charge stored using a unique cross-sectional area of the plates. The temperature was noted to reduce the potential capacitance as it increases while short distance allows high capacitance.
The main purpose of this study is to synthesize and investigate the optical and electrical properties of zinc sulphide (ZnS) thin film which has some interesting optoelectronic properties. The films were grown by chemical bath deposition (CBD) technique on clean soda-lime substrates at room temperature (300k). The films were characterized using Fourier transform infrared spectroscopy (FTIR), Ultraviolet-Visible spectroscopy (UV-Vis), and Four point probe measurements. The FTIR spectrum of the film revealed the characteristic ZnS absorption bands below 800 cm-1. The optical properties were studied in the spectra range of 300 to 1500 nm. The film revealed an average transmittance of above 80% in the visible and near infrared regions with a band gap of 3.30 eV. Optical constants of refractive index, extinction coefficient, electrical susceptibility, dielectric loss were estimated at λ = 800 nm. The values of 1.25 Ω. cm and 8.0 ×10-1 (Ω. cm)-1 were obtained as the electrical resistivity and conductivity respectively. The determined properties categorize ZnS thin film as a promising material for various optoelectronic devices.
The objective of this study is to develop a process for producing alkali-resistant zirconium-containing glasses for use as a heavy metal retention matrix contained in fly ashes. For this, we have developed 5 glass compositions: Two alkali-resistant model glasses type CEMFIL, V1 (with zirconium and without heavy metals) and V2 (with zirconium and heavy metals), then three glasses of fly ashes V3 (without zirconium and with heavy metals), V4 (with 30% of V3, zirconium and heavy metals) and V5 (with 60% of V3, zirconium and heavy metals). V4 and V5 are obtained using V3 as raw material and supplementing with SiO2, ZrO2 and Na2O to give them alkali-resistant properties. Differential thermal analysis show a glass transition temperature Tg of 656°C for V1, 616°C for V2, 615°C for V3, 641°C for V4 and 664°C for V5. Extremely small peaks of alumina can be observed on the V1, V2 and V3 glasses and peaks of ZrO2 only on the V5 glass. Surface analysis of glasses show that they are essentially homogeneous although we note the presence of some heterogeneities: V1 and V2 contain small crystals of ZrO2, V3 has a slight crystallization of Fe chromite spinel (CrO4) and V5 contains large crystals rich in zirconium. This study has shown that all glasses are totally amorphous. Also, alkali-resistant fly ashes glasses V4 and V5 are the most resistant to leaching and the least attacked in alkaline medium than CEMFIL type glasses V1, V2 and V3.
Waste paper and sawdust poses huge problems as degrading urban environment, producing offensive odor during rain and pollute the air with smoke when burnt indiscriminately, thus contributing to environmental degradation and global warming. In addition, if not timely disposed, becomes breeding places for worms and insects. There is therefore need for its proper utilization. This study aims to determining selected physical and mechanical properties of medium density fibreboard produced from waste paper and sawdust. Heterogeneous wood sawdust from logs and waste papers were purchased, hence board formation was done with respect to density and blending proportion after which it was prepared for testing. The mean water absorption and thickness swelling were 87.83±8.51% and 28.61±5.28% for the 850kg/m3 density board, while 84.09±8.21 and 28.03±4.05 were obtained for the 1000kg/m3 density board. Meanwhile, 1.32±0.14 and 15.95±5.05 N/mm2 were obtained for Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) for 850kg/m3 density board while 1.35±0.14 and 19.04±5.05 N/mm2 for 1000kg/m3 respectively. Density of boards formed was not found to significantly affect the selected physical and mechanical properties whereas blending proportion does. However, board density of 1000kg/m3 with blending proportion of 0/100 was most dimensionally stable.
G. arborea wood is a preferred choice for making musical instrument in Nigeria. However, its utilization is solely dependent on indigenous knowledge. Meanwhile, for optimum acoustic performance there is need to study acoustic properties of wood. Thus, this work aim to study the acoustic properties of G. arborea wood. Three trees of G. arborea with 25 ± 2 cm in diameter at breast height (DBH) were obtained. From each tree, bolts of 60cm in length were collected axially, and wood sample of (R x T x L) were obtained radially from each bolts. The samples were then prepared for testing. Fundamental frequency longitudinal vibration method was used to determine acoustic properties of the wood. Hence, necessary model and equations were used to calculate other acoustic parameters. The fundamental frequency, velocity of sound, longitudinal elastic modulus, specific longitudinal elastic modulus, damping factor, acoustic coefficient (K), sound quality, acoustic conversion efficiency, and impedance obtained in this study were 1095.02 ± 20 Hz, 4848.58 ± 77 m/s, 9.34 ± 0.35 GPa, 23.57 ± 0.74 GPa, 0.0039 ± 0.00, 12.30 ± 0.29 m4kg-1s-1, 279.64 ± 21.64, 3435.66 ± 278 m4kg-1s-1, 1.9119 x 106 ± 4.8 x 103 kg/m2s respectively. Meanwhile, no significant differences were recorded for acoustic variables tested axially and radially, except for K. Furthermore, values obtained in this work compared favorably with some known acoustic species. Conclusively, this work was able to conduct a study on some acoustic properties of Gmelina arborea wood and thus found G. arborea wood suitable for acoustic purpose. However, selection of wood for acoustic function should be purpose driven.
