Experimental Analysis of Cable Distance Effect on Signal Attenuation in Single and Multimode Fiber Optics

Losses during transmission and high demand of high data rate by the end users have become the biggest challenges facing the telecommunication industries worldwide with Nigeria inclusive. Fiber optic cable as a channel of communication has been adapted worldwide in solving these problems but there is a little limitation in the place of multimode fiber in long distance communication. This paper focuses on the effect of changes in distance on transmitted bandwidth on single mode and multimode fiber. Two cases were considered during this research; (a) with optical amplifier placed in between multimode fiber and (b) without optical amplifier in between multimode fiber. Readings were taken at various distances when specific bandwidth ranging from 50Mbps to 500Mbps was transmitted from the base station to the various distances and it was observed that there was no significant changes in bandwidth received at specified distances (100, 200, 300, 400, 500 etc) m when using single mode fiber, there was a drastic reduction in bandwidth when it get to a distance of 300m when using multimode. When optical amplifier was placed in between the multimode fiber at some selected distances after 400m from the transmitting BTS, it was noticed that the drastic reduction in transmitted bandwidth was almost eliminated, thereby proven that multimode fiber can be use in long distance communication provided optical amplifiers are incorporated in between the distance to bust the signal strength

Effect of laser power on the microstructure and microhardness property of hybrid fabricated Ti6Al4V based metal matrix composite

Abstract: Several surface coatings on Ti-6Al-4V alloy using laser treatment technique have been investigated in this paper. A hybrid Ti-6Al-4V based metal matrix composites system was also successfully fabricated. This was possible using three hoper system which contained 3.8 vol. % of Ti-6Al-4V and a small amount 0.1 B4C and 0.1 BN respectively. Two different laser powers “2000 W and 1400 W with scanning speed of 1.0 were employed. The idea of these powder coatings and reason for investigating the different Laser power is to evaluate the influence of laser power on the surface morphology and hardness property of Ti-6Al-4V/B4C/BN alloy systems. The hardness result of experimental showed a general improvement. The hardness revealed that the Ti-6Al- 4V/B4C/BN system fabricated at 2000W showed a hardness improvement as high as 640.4 HVO.5 compared to the as receive Ti-6Al-4V substrate Hardness value of about 357.3 HVO.5 and that of 1400W recorded a hardness value of 886 HVO.5. The percentage increase from the as received Ti-6Al-4V alloy was 147.9% and 79.2% respectively. Problems to be solved and the prospective application of laser modification of the hybrid titanium alloy formed were also highlighted

Crude Oil Spills in the Environment, Effects and Some Innovative Clean-up Biotechnologies

Crude oil, refined petroleum products, as well as polycyclic aromatic hydrocarbons are ubiquitous in various environmental compartments. They can bioaccumulate in food chains where they disrupt biochemical or physiological activities of many organisms, thus causing carcinogenesis of some organs, mutagenesis in the genetic material, impairment in reproductive capacity and / or causing hemorrhage in exposed population. The cause / effect of oil pollutant are usually quantified by using biological end point parameters referred to as biomarkers. Contamination of soil arising from spills is one of the most limiting factors to soil fertility and hence crop productivity. These deleterious effects make it mandatory to have a counter measure for the petroleum hydrocarbon pollutant in the environment. Bioremediation of petroleum hydrocarbon-contaminated environment is a potentially important application of Environmental Biotechnology. In this approach microorganisms are utilized under some specified conditions to ameliorate the negative effects in a cost-effective and environmentally friendly approach. The main strategies in bioremediation of oil spills, which include bio-stimulation, nutrient application, bio-augmentation, seeding with competent or adapted hydrocarbono-clastic bacteria or their consortium, and genetically engineered microbes, are reviewed. Although the promise of bioremediation is yet to be realized, innovative areas in Environmental Biotechnology for oil spill clean up are highlighted