IOSR-JAP   Volume-7 ~ Issue-6 ~ Nov-Dec 2015

ABSTRACT: In40 Se60 thin films with different thicknesses (300,500, and 700nm) have been deposited by single source vacuum thermal evaporation onto glass substrates at ambient temperature to study the effect of thickness and on its structural morphology, and electrical properties. AFM study revealed that microstructure parameters such as crystallite size, and roughness found to depend upon deposition conditions. The DC conductivity of the vacuum evaporated In40 Se60thin films was measured in the temperature range (293-473)K and was found to increase on order of magnitude with increase of thickness. The plot of conductivity with reciprocal temperature
suggests, there are two activation energies Ea1and Ea2 for In40 Se60 for all thicknesses which decreases with increasing thickness

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ABSTRACT: Electrical resistivity survey was carried out to investigate the groundwater potential of Abakaliki urban, a sedimentary area with the oldest Cretaceous rocks (sandstones and shales) which are of Albian age. The equipment used for the survey include, ABEM terrameter (SAS, 300C), four electrodes, hammer, four reels of wires, connecting cords, measuring tapes and global positioning system. The survey was carried out in three different locations. The field layout employed was the schlumberger array. The result of the survey shows that the average resistivities are 1337.06m for the first layer, 5914. 34m for the second layer, 1277. 59m for the third layer, 189.

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[4]. Egboka, B.C.E. and Okpoko, E.I., (1984): Gully erosion in the Agulu Nanka region of Anambra state Nigeria. In: Challenges in African Hydrology:335-347.
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ABSTRACT: The automatic three phase power system selector was designed and constructed. The device automatically switches over to the alternative phase that has current when there is power outage or extremely low current in the phase which the load is connected without the power being off. The selector links the load and the other phases and relay switches allowing the usage of the remaining phases where there is outage on the mains source without disturbing or interrupting the load. It maintains constant power supply to the load by automatically activating the phases when the need arises. This safeguards the electronics system from being damaged and burnout as a result of voltage instability, collapse, insistent outages which are paramount in under developed and developing countries.

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[2]. Nweke F. U. (2010). Workshop Processes and Practice: Electronics and Electrical Installation. IZU Prints Abakaliki Nigeria
[3]. Guasch L., Corcoles F. and Pedra J. (2000). Effects of Unsymmetrical Voltage Sag types E, F and G on Induction Motors. Proceedings of the conference on Harmonics and Quality of Power 3(3) 796-803