288 research outputs found
Preparation and Evaluation of Electrical Properties of Plastic Composites Developed from Recycled Polystyrene and Local Clay
In this study, the development of polymer composites was achieved from local clay material and waste polystyrene by cold pressing method, the preparation, electrical, and physical behaviours of clay-polystyrene composites are described. Polystyrene based resin (PBR) was produced from waste polystyrene by solvolysis in petroleum solvent and mixed with the 100ÎĽm clay particles at 10%, 20%, 30%, and 40% clay contents. Composite panels were prepared and tested for Physical and electrical properties. Metallurgical microscope was used for the microstructural studies. It was found that with the increase in clay content in PBR from 0 to 40%, there was a rise in density of the composite by about 11% with a simultaneous decrease in the void fraction or porosity from 5.3 % to 1.5%. It was also observed that the polymer composite with the filler loading of 40 wt% has the highest conductivity value of 1.88E-07 S/cm. The comparison of micrographs at 40x and 100x indicated a good dispersion and distribution of clay particles in the polystyrene matrix. The polymer composites produced can be adapted for applications where electrostatic dissipative materials are required.KEYWORDS: Electrical property, iron fillings, plastic composite, recycled polystyrene, clay particles
Deterministic Model for Noise Dispersion from Gas Flaring: A Case Study of Niger – Delta Area of Nigeria
Noise is an audible acoustic energy that adversely affects the health, physiological and psychological well being of the individuals or populations. One of the major pollutants from gas flaring is the noise emanating from gas flaring stations in the Niger – Delta
area of Nigeria. Noise dispersion produces many adverse effects on man and animals.
Experimental analysis of noise dispersion and weather conditions used for simulation has been carried out, the modeling and simulation of noise dispersion from flare stations using visual basic programme is the main focus of this work. Results obtained shows some
variation between the simulated results and experimental results, with correlation coefficient ranging from 0.955 – 0.995. Simulation results of the developed model show that the noise intensity level reduces with increasing in distance from the flare point and that
weather conditions has an important influence on noise dispersion
Efficient Item Image Retrieval System
Content based image retrieval system is a very
effective means of searching and retrieving similar images from
large database. This method is faster and easy to implement
compare to text based image retrieval method. Ability to extract
discriminative low level feature from these images and use them
with appropriate classifier is factor in determining retrieval
result. In this work efficient item image retrieval system is
proposed. The system utilizes Haar wavelet transform, Phase
Congruency and Support Vector Machine. Haar wavelet
transform acted on image to form four sub-images. Texture
feature is extracted from smaller image blocks from detailed
bands and it was combined with shape feature from
approximation band to form feature vector. Feature distance
margin is achieved between query image and images in the
database using Support Vector Machine (SVM). The
effectiveness of the system is confirmed from output retrieval
results
Weight loss and microstructural studies of stressed mild steel in apple juice
This study investigated the effect of internal stress of mild steel on its corrosion behaviour in apple juice by weight loss and microstructural analyses....read full pape
Improving mechanical properties of aluminium alloy through addition of coconut shell-ash
This paper investigates the microstructure and mechanical properties of aluminum alloy (Al-Si-Fe) reinforced with coconut shell-ash particulate. The aluminium (Al-Si-Fe) alloy composite was produced by a double-stir casting process at a speed of 700 rpm for 10 and 5 minutes at first and second stirring respectively. The samples produced from addition of 0-15 wt% coconut shellash particles (CSAp) were prepared and subjected to microstructural and mechanical properties testing. The results of the microstructural analysis of the composite reveal a fairly uniform distribution of the coconut shell-ash particles in the matrix with increase in volume fraction of CSAp. The mechanical property test results revealed that, hardness of the developed composite increased with increasing percentage weight of CSAp. Also the tensile and yield strength at 0.2% offset values of Al-Si-Fe/CSAp composite increased with percentage increase in CSAp up to 9% addition above which a little decrease in both tensile and yield strength was observed.Keywords: Matrix, coconut shell, mechanical properties, stir- casting, particulate, reinforcement
Predictive mathematical modeling and computer simulation of direct ethanol fuel cell
Abstract: The challenges of finding a better substitute of energy as well as the short comings identify with direct ethanol fuel cell, this includes; high anode over potential and crossover necessitate the need to investigate the influence operating parameters on the performance of fuel through computer simulation. This study focus on the development of a predictive mathematical modeling for direct ethanol fuel cell for the purpose of investigating the influence pressure, temperature cathode and reactants concentration on the performance, efficiency and heat generated by the cell. Results obtained indicate that increase in operating temperature resulted led to decrement in output voltage and cell efficiency, while same condition of increasing the temperature positively favour the heat generated from the cell. Simulated results also show that cell performance is improved with increase in concentration of the fuel (ethanol) and oxidant (oxygen). It can be inferred from this study that the cell performance of DEFC can be theoretically predicted with the developed model
Parametric effects on leaching behavior of nickel-copper matte in ammonia
Abstract: Please refer to full text for abstrac
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