Study of Landcover Change in Yelwa-Heipang Area of Plateau State, North-Central Nigeria: A Geoinformatics Approach

This study is a research programme carried out to detect the change in land use/land cover of Yelwa-Heipang area of Plateau State, North Central Nigeria. It lies within the South-Eastern part of the Jos-Plateau. It is about 40 km South of Jos city. It is located between latitude 9°35'16.65" N, longitude 8°52'29.91" E and Latitude 9°38'38.92" N, longitude 8°57'03.87" E (Naraguta topomap, sheet 168S.E). Two sets of Landsat images of 1975, 1986 and NigeriaSat-X image of 2012 were subjected to various image processing techniques and a supervised classification was carried out on the various images using ILWIS (Integrated land and water information system) software. The classification scheme used are bare-surface, built-up, farmland and vegetation. A follow up field work was carried out to confirm the results of the classification. The results were subjected to various statistical analyses and it shows natural vegetated area coverage increased from 5.80 sqkm in 1975 to 18.47 sqkm in 1986 and later reduced to 16.85 sqkm in 2012. Non-vegetated area which comprised built-up area, farmlands and bare surface, decreased from 42.2 sqkm in 1975 to 33.82 sqkm in 1986, then to 35.86 sqkm in 2012.The rate of change of natural vegetation between 1975 and 1986 was 1.152 sqkm per annum, while that of 1986 and 2012 was 0.108 sqkm per annum. Loss of naturally vegetated area in Yelwa-Heipang Barkin-Ladi is mainly as a result of urban growth and expansion, farming and gully erosion. Another important issue in the study area is the problem of soil erosion. In the past mining activity had led to accelerated gully erosion which has stripped substantial areas of lands of their vegetations. This has led to the formation of bare surface. Land cover of the study area during the period between 1975 and 2012 changed from a forested area to other land uses as a result of increase in population, demand for land for agricultural purposes and increase in the demand for firewood

Correlation between molar concentration and properties of sprayed copper oxide thin films

Copper oxide precursor solutions containing 0.10 M, 0.15 M, 0.20 M and 0.25 M concentration of copper were deposited on a glass substrate using the spray pyrolysis method. The structural, optical and surface properties of the resulting copper oxide thin films were studied using x-ray diffraction, UV–visible spectroscopy and scanning electron microscopy. Structural studies indicate the absence of secondary phases of copper oxide in the spraydeposited copper oxide thin film with 0.10 M concentration. Optical characterization reveals highest absorbance and lowest transmittance at 0.10 M concentration with an estimated optical bandgap of 1.2 eV. The SEM micrographs reveals a non-porous and comparatively more homogenous surface at 0.10 M concentration. The results show that molar concentration of copper plays a vital role in the development of copper oxide (CuO) thin film for solar cell application. The results have further validated the theoretical predictions of the GW approximations on phases of copper oxide thin films

EXPERIMENTAL DESIGN AND DEVELOPMENT OF LOCALLY MADE PARABOLIC TROUGH SOLAR THERMAL COLLECTOR UNIT

The design and analysis of Parabolic Trough Solar Thermal Collector (PTSTC) system used to generate hot/steam water for domestic and industrial purposes were carried out. The parametric studies were also conducted on the collector, study the effectiveness of hot water production for potential applications. The PTSC was designed with Parabolic Software version 2.0. The fabrication and design were done with a combination of reflector surface, reflector support, absorber pipe and wooden stand. The absorber pipe was painted in black colour while the trough was manually operated. The flow of water in the system follows the recycling process repeated during data acquisition. The ambient temperature, the inlet and outlet temperature of the receiver and total solar radiation on the PTSC were recorded. Different flow rate of the Heat Transfer Fluid (HTF) was tested at 0.021, 0.022, 0.023 and 0.024 kg/s respectively. Collected data showed the maximum outlet water temperature attained as 72oC. The average outlet temperature increased from 36oC at 10:30 hour to 69.84oC at 16:00 hour. The average beam radiation during the collection period was 699 W/m2. Different flow rates show that the lower the flow rate, the higher the efficiency of the system. The study revealed that the developed parabolic trough solar collector is viable for the production of sterilized water and low stage steam for domestic and industrial purposes