Papers by Keyword: Conventional

Abstract: Indonesia is a tropical country with high rainfall, which necessitates pavement with higher void content and good drainage conditions. The quality of road pavement depends on the materials used. One type of asphalt mixture with high void content and permeability but low stability is porous asphalt. This is due to the composition of porous asphalt, which consists predominantly of coarse aggregates compared to fine aggregates. This study utilizes waste tires, Low-Density Polyethylene (LDPE), gilsonite, and 60/70 penetration asphalt as binders, referred to as modified asphalt, in porous asphalt mixtures. The objective of this study is to determine the Optimum Asphalt Content (OAC) using waste tires, LDPE, gilsonite, and 60/70 penetration asphalt as binders in porous asphalt mixtures and to compare it with the OAC of conventional asphalt. The method used in this research is based on the Australian Asphalt Pavement Association (AAPA) (2004) method, employing open-graded porous asphalt with a maximum aggregate size of 14 mm. According to AAPA (2004), OAC determination requires three parameters: Cantabro Loss (CL), Asphalt Flow Down (AFD), and Voids in Mix (VIM). The study began with testing the physical properties of aggregates and asphalt, both conventional and modified. After testing the physical properties, the next step was determining the optimum asphalt content. The OAC obtained for porous asphalt mixtures using modified asphalt as a binder was 5.3%, while the OAC for conventional asphalt was 5.75%, serving as a comparison.

Abstract: Sinterability of zinc doped calcium phosphate (CaP) sintered via conventional pressureless and two step sintering methods was investigated. The starting powders have been synthesized through sol-gel method with zinc concentration varied in the range of 0, 1, 4, and 10mol%. After uniaxial pressing, the compacts were sintered via conventional pressureless sintering. The dense samples were studied in terms of the phase stability, relative density, Vickers hardness, and fracture toughness. The phase of samples was hydroxyapatite and β-tricalcium phosphate. The presence of Zn caused a change in the sintering behaviour of dense calcium phosphate. Zn doping has improved relative density of 4mol% Zn-doped by 8.1% compared to undoped fired at 1300°C. The maximum fracture toughness of 1.43 MPa.m^1/2 and Vickers hardness of 3.44 GPa were achieved at 1200°C by 4 mol% Zn-doped. The low Vickers hardness and fracture toughness obtained for dense samples sintered of two step sintering compared to conventional pressureless sintering is due to the low measured bulk density. This study showed that conventional pressureless sintering was beneficial in producing high toughness of Zn doped CaP.

Abstract: Nigeria is endowed with abundant energy resources, both conventional and renewable, which can potentially provide the country with a sufficient capacity to meet the ambitions of both urban and rural Nigerians of a full, nationwide electrification level. Yet, Nigeria has one of the lowest consumption rates of electricity per capita in Africa. With the demand superseding the generation, there is inequitable access of rural communities to the electricity service in the country. There are inherent obstacles militating against the effective implementation of an orderly energy policy in Nigeria. The inefficiencies over shadowing the allocation of energy resources coupled with the near depletion of fossil fuels, make it imperative for the country to exploit its huge natural renewable resources to avoid a worsening energy supply scenario and provide feasible solar water pump to rural dwellers. This paper presents the applications of solar water pumping which are already quite significant and are growing at steady rate. Solar energy is suitable for small-scale water pumping in remote areas where the demand is regular, such as for drinking water, but it may also be used for irrigation. Most areas in Nigeria have climates suitable for solar pumping. A review is given of the use of solar energy for water pumping to improve the living conditions of the population in rural areas and to develop techniques for utilization of solar energy in a tropical environment condition. Results, suggests that, solar powered water pumping must be encouraged, promoted, invested, implemented, and demonstrated by full scale in Nigeria.

Abstract: Soil adheres to the surfaces of soil engaging components of earthmoving machinery and equipment. It has been pbserved that up to 50% of energy may be consumed in overcoming adhesion and friction of soil to the surfaces of soil engaging components of agricultural and earthmoving machinery. Surface morphology, chemical composition, elasticity, lubrication mechanism and electric osmosis play significant roles in reducing adhesion, friction and energy consumption of various equipment. Some of these techniques have very limited application in the practical field conditions because of the time and amount of fluid required to achieve the desired results. Whereas other techniques are effective in reducing adhesion and friction and improving work quality of these machines and equipment. This paper analyses the forces including the drafts of conventional and bionic bulldozing blades operating under identical conditions using mathematical modelling. The force analysis showed that both adhesion and friction play major role in reducing drafts of earrthmoving machinery. It is also worth stating that both the surface morphology and the construction materials play important role in reducing adhesion and friction of ground eganging components of earthmoving machinery.

Abstract: Plastics are synthetic polymers, made from petroleum and its derivatives which are non biodegradable. Today, more people used plastic bags to support their activities ,which caused the supply of plastic shopping bags to increase in large number. Plastic bags, eventually, are usually used as garbage which would cause negative impact on the environment. Environmental friendly plastic bags are made from renewable raw materials, such as starch from cassava, corn or others. There are the ones entirely starch based such as Enviplast (biodegradable); the ones with partial mixture of starch with plastic ores such as Ecoplas (biodegradable), the ones plastic ores are formulated with additives Oxium (oxodegradble), and conventional made from plastic ores only. Distinguishing characteristics of samples plastic shopping bags which were taken from domestic and abroad supermarkets can be seen from the result of FTIR, SEM, and AAS analysis along with burial in soil. Density of domestic plastic bag (1.119 g/cm³ ) are 49.55% smaller than samples abroad 2.258 g/cm^{3 .}This means that in the country, a space to hold trash bags in the same weight needed almost 2x larger. Another discovery are some plastic shopping bags are labeled eco-friendly ,but had conventional plastic characteristisc .

Abstract: A modified hopper design of the conventional cassava grater and its concomitant productivity improvement is presented. One of the sides of the inverted truncated rectangular pyramidal hopper was hinged at the lower end and swung through angle of 15 to 30 degrees. This flapper swing served as feed for the rotary grater. The flapper allowed the cassava tubers to be fed over a larger grater surface area permitting cassava feed over an angle of 120 degrees instead of the usual 90 degrees. It further allowed the variation of the space between the rotary grater and the hopper thereby enhancing complete maceration of the tubers. The presence of ungrated cassava chips in the macerated mash common feature with conventional graters was reduced to negligible proportions. A process improvement of up to 100 per cent in thru-put was obtained compared with the conventional graters.