ABSTRACT Nowadays, the destruction and pollution of humane environment has produced an ever growing awareness worldwide of the need for more effective sedimentation processes. The main aim of this project was to design and fabricate an experimental sedimentation rig with the objective to determine the rate of settling against time using calcium carbonate as a test sample.The rig consists mainly of the cylindrical tank, valves, motor, stirrer, and the sight glass. For the test run, 82 litres o...
ABSTRACT Nowadays, the destruction and pollution of humane environment has produced an ever growing awareness worldwide of the need for more effective sedimentation processes. The main aim of this project was to design and fabricate an experimental sedimentation rig with the objective to determine the rate of settling against time using calcium carbonate as a test sample.The rig consists mainly of the cylindrical tank, valves, motor, stirrer, and the sight glass. For the test run, 82 litres o...
The noise pollution is a major problem for the quality of life in urban areas. This study was conducted to compare the noise pollution levels at busy roads/road junctions, passengers loading parks, commercial, industrial and residential areas in Ilorin metropolis. A total number of 47-locations were selected within the metropolis. Statistical analysis shows significant difference (P < 0.05) in noise pollution levels between industrial areas and low density residential areas, industr...
A l’heure où la viande constitue un aliment de luxe pour les populations pauvres, les légumineuses entre autres le soja constituent une alternative. Malheureusement, sur les sols fortement altérés de Lubumbashi, son rendement demeure de loin inférieur au potentiel même de la culture. Les effets de compost de Tithonia diversifolia sur la croissance et le rendement de soja ont été étudiés au cours de la saison culturale 2013-2014 sur un sol dégradé de Lubumbashi (R.D. Congo). S...
Assessment of the response of maize (Zea mays L.) planted between hedgerows of Tithonia diversifolia in Lubumbashi, DR Congo Objective: Two trials were carried out over time at the Centre de Recherche Agroalimentaire (CRAA) and aimed at evaluating the behavior of maize cultivation in hedgerows of Tithonia diversifolia (Mexican sunflower). Methodology and results: The experimentation design was a completely randomized, the distances from maize planting lines to the T. diversifolia hedge ar...
Abstract: Melon dehusking is often associated with lots of manual labour and stresses. In order to reduce the stress and boredom usually involved in manual dehusking of melon process, a melon dehusking and separation machine was designed, constructed and tested for operation as presented in this paper. The melon dehusking machine operates on the principle of attrition/friction as opposed to the use of an impact force in the dehusking chamber for shelling of melon seeds. This principle resu...
ABSTRACT This project deals with the design and development of restaurant order meal system, in order to reduce the number of staff. In meal ordering project, you can request for any kind of food or drinks available in the restaurant which contains the menu embedded in each button. Microcontroller is the central processing unit CPU of this project and it also consists of Bluetooth it is said to be the main component used in this project. Microcontroller gets the coordinates from the Bluetooth...
ABSTRACT Beneficial bacteria that colonize the root of plants and are capable of stimulating the growth of plants directly or indirectly are called plant-growth promoting rhizobacteria. The objective of this study was to isolate and characterize plant-growth promoting rhizobacteria from the rhizosphere of some selected vegetables collected at different locations in Ago-iwoye, Oru and Ijebu-Igbo in Ijebu-North local Government Area of Ogun state, using general microbiological and biochemical t...
Abstract The project DESIGN AND CONSTRUCTION OF A 20-METRE DISTANCE REMOTELY CONTROLLED METAL DETECTOR is used for detecting metallic objects such as phones, bombs, and other metallic objects that are hidden from view. The design is based on the principle of the Resonant Frequency Oscillator (RFO) metal detectors in which oscillation is a function of parallel connection of an inductor and a capacitor operating in resonance. The project is divided into two sections. The transmit...
A study was carded out with the goal of obtaining high open circuit voltages (Voc) in a-Si:H n-i-p solar cells, taking into account the evolutionary nature of the microstructure of the p-layers during growth. It is found that cells with players in the protocrystalline Si:H growth regime give the highest values of Voc not those with microcrystalline Si:H p-layers. Evidence for this conclusion is presented whereby Voc is related directly to the microstructure of the p-layers, as characterized u...
In studies of hydrogenated amorphous silicon (a-Si:H) n–i–p solar cells fabricated by rf plasma-enhanced chemical vapor deposition (PECVD), we have found that the maximum open circuit voltage (Voc) is obtained by incorporating p-type doped Si:H layers that are protocrystalline in nature. Specifically, these optimum p layers are prepared by PECVD in the a-Si:H growth regime using the maximum hydrogen-to-silane flow ratio possible without crossing the thickness-dependent transition into the...
For the first time direct correlations are obtained between the light induced changes under 1 sun illumination in the properties of a-Si:H and those in the characteristics of p-i-n cells incorporating identically-prepared i-layers. These correlations were obtained after account was taken of the effects that the location of the electron and hole quasi-Fermi levels have on the carrier recombination that occurs through the different gap states. The changes in midgap state density, as measured on...
As both population and energy use per capita increase, modern society is approaching physical limits to its continued fossil fuel consumption. The immediate limits are set by the planet’s ability to adapt to a changing atmospheric chemical composition, not the availability of resources. In order for a future society to be sustainable while operating at or above our current standard of living a shift away from carbon based energy sources must occur. An overview of the current state of active...
Forward bias current–voltage characteristics (JD–V) were studied for both p–i–n (superstrate) and n–i–p (substrate) (a-SiC:H p)/(a-Si:H i) solar-cell structures having different p/i interface layers and different thickness i-layers. Contributions of the p/i interfaces to the JD–V characteristics were separated, and the dependence on the thickness of the i-layers was established. Equivalence was observed in a comparison of the characteristics of p–i–n and n–i–p cells....
To take into account the presence of multiple light-induced defect states in hydrogenated amorphous silicon (a-Si:H) the evolution of the entire spectra of photoconductive subgap absorption, α(hν), has been analyzed. Using this approach two distinctly different light-induced defect states centered around 1.0 and 1.2 eV from the conduction band edge are clearly identified. Results are presented on their evolution and respective effects on carrier recombination that clearly point to the impor...