Journal Advanced Journal of Graduate Research-
Advanced Journal of Graduate Research, Volume 6, pp 14-30; doi:10.21467/ajgr.6.1.14-30
Abstract:Increasing greenhouse effect due to the burning of fossil fuels has stirred the attention of researchers towards cleaner and efficient technologies. Direct carbon fuel cell (DCFC) is one such emerging technology that could generate electricity from solid carbon like coal and biogas in a more efficient and environmental-friendly way. The mechanism involves electrochemical oxidation of carbon to produce energy and highly pure carbon dioxide. Due to higher purity, the produced carbon dioxide can be captured easily to avoid its release in the environment. The carbon dioxide is produced in a gaseous state while the fuel used is in a solid state. Due to different phases, all of the fuel can be recovered from the cell and can be reused, ensuring complete (100%) fuel utilization with no fuel losses. Moreover, DCFC operates at a temperature lower than conventional fuel cells. The electric efficiency of a DCFC is around 80% which is nearly double the efficiency of coal thermal plant. In addition, DCFC produces pure carbon dioxide as compared to the thermal power plant which reduces the cost of CO2 separation and dumping. In different types of DCFCs, molten carbon fuel cell is considered to be superior due to its low operating temperature and high efficiency. This paper provides a comprehensive review of the direct carbon fuel cell technology and recent advances in this field. The paper is focused on the fundamentals of fuel cell, history, operating principle, its types, applications, future challenges, and development.
Advanced Journal of Graduate Research, Volume 6, pp 1-13; doi:10.21467/ajgr.6.1.1-13
Abstract:The present article is the successor of Solar Dynamical Processes I. The previous article was focused on the Sun, its magnetic field with an emphasis on various dynamical processes occurring on the Sun, e.g. sunspots, prominence and bright points which in turn plays a fundamental role in regulating the space weather. This article is emphasized on the solar dynamical processes and develop an extensive understanding of the various phenomena involved in their origin. The article also covers various models and hypothesis put forward by pioneer scientists on the basis of their observation by space-borne and ground-based instruments. This article shade light over a wide range of dynamical processes e.g., solar flares, coronal mass ejections, solar jets and coronal holes. Solar jets, the small-scale transient activities are found to have association with the other transient activities (e.g., mini-flares and mini-filaments). Flares as well as the coronal mass ejections are responsible for releasing a large amount of high energy charged particles and magnetic flux into the interplanetary space, and are being considered as the main drivers of space weather.
Advanced Journal of Graduate Research, Volume 5, pp 61-70; doi:10.21467/ajgr.5.1.61-70
Abstract:The Genetic Algorithm is one of the advanced optimization techniques frequently used for solving complex problems in the research field, and there are plenty of parameters which affect the outcome of the GA. In this study, a 25-bar truss with the nonlinear constraint is chosen with the objective to minimize the mass and variables being the discrete area. For the same, GA parameter like Selection Function, Population Size, Crossover Function, and Creation Function are varied to find the best combination with minimum function evaluation. It is found that the Uniform selection gives the best result irrespective of the creation function, population size or crossover functions. But this is at the cost of a large number of function evaluations, and the other selection function fails to reach the global optimum and has a smaller number of function evaluation count. If the analysis of selection function is done one at a time, it is seen that all Cases performs better in Roulette but, Case A which is non-integer type with 200 population size being computationally cheaper than Case B and C of population size 300. In the Tournament selection, Case A, B with smaller population size and Case C with higher population size performs better. Case C performs better at Remainder selection with smaller population size, and Case A and B for Stochastic Uniform with higher population size. And, it is clear that the function evaluation count increases with the population size in every Case from this study.
Advanced Journal of Graduate Research, Volume 5, pp 55-60; doi:10.21467/ajgr.5.1.55-60
Abstract:This paper describes the hardware of movable Headlight & Foglight system for vehicles. It has been found that the majority of accidents take place due to the invisibility of road at night & in fog. So, it becomes necessary that we get a clear vision during the night & in fog so as to avoid accidents. Therefore, the following research represents the rotation of headlight & foglight with the rotation of wheels. In this system used rack & pinion arrangement which give the drive to the optical axes on which headlight & foglight are mounted so when the links are moved with steering arm that gives predefined motion to headlight and foglight. Hence the light from the Headlight & Foglight focuses properly on the road, also while taking turn the driver coming from the opposite side can easily notice the upcoming vehicle & so the number of accidents is minimized. In this paper, we have defined a novel approach movement of foglight along with the headlight.
Advanced Journal of Graduate Research, Volume 5, pp 43-54; doi:10.21467/ajgr.5.1.43-54
Abstract:Corrosion is a severe matter regarding the most of metal using industries such as the crude oil refining. The formation of the oxides, sulfides or hydroxides on the surface of metal due to the chemical reaction between metals and surrounding is the corrosion that highly depended on the corrosive properties of crude oil as well as the chemical composition of ferrous metals since it was expected to investigate the effect of Murban and Das blend crude oils on the rate of corrosion of seven different ferrous metals which are used in the crude oil refining industry and investigate the change in hardness of metals. The sulfur content, acidity and salt content of each crude oil were determined. A series of similar pieces of seven different types of ferrous metals were immersed in each crude oil separately and their rates of corrosion were determined by using their relative weight loss after 15, 30 and 45 days. The corroded metal surfaces were observed under the microscope. The hardness of each metal piece was tested before the immersion in crude oil and after the corrosion with the aid of Vicker’s hardness tester. The metallic concentrations of each crude oil sample were tested using atomic absorption spectroscopy (AAS). The Das blend crude oil contained higher sulfur content and acidity than Murban crude oil. Carbon steel metal pieces showed the highest corrosion rates whereas the stainless steel metal pieces showed the least corrosion rates in both crude oils since that found significant Fe and Cu concentrations from some of crude oil samples. The mild steel and the Monel showed relatively intermediate corrosion rates compared to the other types of ferrous metal pieces in both crude oils. There was a slight decrease in the initial hardness of all the ferrous metal pieces due to corrosion.
Advanced Journal of Graduate Research, Volume 5, pp 16-23; doi:10.21467/ajgr.5.1.16-23
Abstract:Quest for higher conversion efficiency and reduced environmental impact has increased the focus on renewable energy sources. Biomass is a sustainable form of energy that can be used as an alternate of fossil fuels through biomass gasification. Gasification is one of the most used methods for converting biomass into syngas that is a usable form of energy. The biomass gasification serves as a promising process for energy production. However, uncertainty in process variables and formation of tar has been a challenge in efficient process design and operation. This paper contains literature review of different models used for gasification, tar removal techniques along with Fischer Tropsch reactions for conversion of biomass to liquid fuels. The paper shows circulating and bubbling fluidized bed gasifier as the most efficient model for tar removal and greater exergy efficiency.
Advanced Journal of Graduate Research, Volume 5, pp 33-42; doi:10.21467/ajgr.5.1.33-42
Abstract:Hybrid power system sizing involves determination of local load and energy resources’ conditions as well as availability of generating system components. Each component of the system is preliminarily sized individually using prevailing load, resource and conversion system’s conditions. The Net Present Cost (NPC), Cost of Energy (COE) may be included in determining the configuration of the most optimal system that can meet all the desired power system’s goals. In order to refine the sizing and design process, a simulation software is used to select and size system components that can serve the load effectively. In this study, a Solar PV, Wind and Grid hybrid power system was systematically sized to meet the demand of a commercial consumer, East African School of Aviation (EASA). HOMER software was used to simulate the operation of the proposed HPS. The most suitable HPS was found to consist of Wind generation of an installed capacity of 200 kW, solar PV of 120 kW and the Grid. This system had an NPC of KSh 77,684,050 and a COE of KSh 8.34/kWh
Advanced Journal of Graduate Research, Volume 5, pp 24-32; doi:10.21467/ajgr.5.1.24-32
Abstract:Laboratory and screenhouse experiment were conducted to assess the symbiotic effectiveness (SE) of rhizobia isolated from southern Guinea savanna, northern Guinea savanna and Sudan savanna of Nigeria and response of promiscuous soybean varieties, TGx1448-2E, TGx1835-10E and TGx1955-10E to inoculation with ten indigenous rhizobia isolates. The soybean varieties were grown on sterilized sand at the screenhouse of the Department of Soil Science and Land Management, Federal University of Technology Minna and watered using Sandsman’s nutrient solution. The treatments were un-inoculated control, mineral nitrogen (urea) and ten rhizobia isolates arranged on a Completely Randomized Design (CRD) and replicated three times. The rhizobia isolates were Sg4, Sg6-3, Gw5, Gw3-2, Bg3, Bg1-4, Sk2-3, Am2, Am6-3 and Kr5-5 isolated from Sabon-gida, Gwada, Birnin-gwari, Shika, Amawa and Karaye sites of Nigerian savanna. The results obtained were subjected to Analysis of Variance using statistical analysis system (SAS 2008) computer software. The treatments mean was separated using Least Significant Different (LSD) at 5% probability. Nodulation and biomass yield of the varieties were assessed at six weeks after planting. Nodules were only produced in inoculated plants, SE was calculated. The result obtained showed that nodule dry weight, SE and shoot dry weight were significantly affected by the interaction between inoculation and promiscuous soybean varieties. Generally, inoculated plants gave higher shoot biomass gain than the un-inoculated control but lower than those treated with urea. The difference between those inoculated and those treated with urea was associated to environmental specificities and higher temperature during the period of the experiment. The SE was highest in northern Guinea savanna isolate reaching 67% and lowest in southern Guinea savanna isolate Sg6-3 recorded 53%. The result showed an SE of less than 100% in all the isolates which implies that the indigenous rhizobia isolates were not superior to the mineral nitrogen.
Advanced Journal of Graduate Research, Volume 5, pp 8-15; doi:10.21467/ajgr.5.1.8-15
Abstract:Al or Al alloy Metal Matrix Composites have wide range of applications i.e. aerospace, automobile etc. due to its lightweight, high tensile strength, high wear resistance. This review paper characterized the SiC particulate reinforced Al Metal Matrix Composites. The SiC particulates are dispersed in Al or Al alloy by liquid state processing route and solid-state processing route. Stir casting liquid processing route has been followed by no. of researchers due to its simplicity and low processing cost and at the time of reinforcement small amount of Mg is added to increase the wettability of SiC in molten Al or Al alloy. When Al or Al alloy reinforced with SiC, then its mechanical and tribological properties are enhanced. The effect of particle size, weight or volume fraction of the SiC on density, porosity, hardness, impact toughness, tensile strength, ductility, sliding wear resistance, slurry erosion resistance, erosion-corrosion resistance, corrosion resistance and fatigue strength of Al or Al alloy MMCs are reported. The effect of extrusion and machinability of the SiC particulate reinforced Al MMCs are also discussed in this review article.
Advanced Journal of Graduate Research, Volume 5, pp 1-7; doi:10.21467/ajgr.5.1.1-7
Abstract:Optimization is the basic tools to study the behaviour of many complicated mechanical systems by having the knowledge of differential equations which determine the system. The basis of this paper was to present a method to estimate the parameters such as spring constant and damping coefficient of the spring damped system by unconstrained optimization using derivative methods Such as quasi-newton method by Broyden-Fletcher-Goldfarb-Shanno and davidon-Fletcher-Powell hessian updating method by using backtracking line search methods along with Armijo’s condition.it uses the output error approximation procedure. It shows the convergence of different methods which are used to estimate the parameters and how accurately they are measured.