ARPN Journal of Engineering and Applied Sciences                         ISSN 1819-6608
   
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ARPN Journal of Engineering and Applied Sciences           November 2009 | Vol. 4  No. 9
   
Title: The secondary effects of lignosulfonate cement retarder on cement slurry properties
Author (s): Joel Ogbonna F.
Abstract:

The primary function of retarders in cement slurry design is to increase the thickening time at higher temperature to allow time for placement of the liquid slurry. This has been the focus in the oil Industry on cement slurry design using retarders. However, test results from this research work using different retarder concentrations indicated that not only the thickening time was affected but the compressive strength, rheological as well as the free fluid properties. Increasing retarder concentration not only resulted to increase in thickening time, but a decrease in both rheological properties and early strength development as well as increase in free fluid results. It is therefore imperative that to optimize a cement slurry design to meet up with design objectives and all boundary conditions, the choice of optimum retarder concentration is critical.

 
 
 
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Title: Development and calibration of an automatic runoff-meter
Author (s): Olotu Yahaya, Olufayo A. A, Akinro A. O and Mogaji Kehinde O
Abstract:

An automatic Runoff-meter using tipping bucket arrangement consists of a pair of water level sensor that send signal to the control circuit through the sensitive micro-switch (P166, N123, P26) was designed and constructed. The design was based on soil and water engineering principles.  The instrument operation was calibrated to tip 0.14 litre of runoff water at every tipping operation with an accuracy of 0.001 litre.  Electromechanical principle was used to establish the tipping mechanism. Calibration tests were carried out on the instrument at different gradients.  The effect of runoff intensity on functional efficiency and speed of the instrument was statistically significant at 5% and 1% confidence levels.  Results show a peak average total functional efficiency of (95.9%) with least speed of (37.4 rpm) at gradient 30 and least functional efficiency (85.2%) and highest speed of 45.7 (rpm) at gradient 70. The results obtained can be used to formulate physics-based deterministic models useful in designing hydraulic structures and for recommending appropriate land management systems.

 
 
 
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Title: Recovering fine iron minerals from Itakpe iron ore process tailing
Author (s): Ajaka E. O
Abstract:

Recovery and concentrate grades in a mineral processing plant are affected by many factors among which are grain size ranges of the liberated minerals, the percentage of natural fines in the ore and constraints imposed by concentrate end-users. The Itakpe iron ore processing plant in Nigeria presently produces a tail containing up to 20-22% iron minerals mostly natural fines in the ore and fines produced inevitably during comminution. This article analyzed the existing circuit and undertook specific recovery tests on the tailing material using simple hindered settling and floatation process for the recovery of fine iron minerals in the tailings. The results showed that concentrates of grades ranging from 41-62% can be attained with the selected processes. Blending and dilution of the concentrates obtained in the recovery processes with a re-cleaned concentrate of the existing plant still produced a supper concentrate of above 70% grade. It is, therefore, recommended that the flowsheet used for the recovery process be integrated with the flowsheet of the existing plant in order to improve recovery the fine iron minerals lost to the waste.

 
 
 
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Title: Co (ii), Ni (ii), Cu (ii), Zn (ii) and Cd (ii) mixed ligand complexes of 6-aminopurine, theophylline and thiocyanate ion, preparation and spectroscopic characterization
Author (s): Shayma A. Shaker, Yang Farina, Sadia Mahmmod and Mohean Eskender
Abstract:

New mixed ligand complexes were prepared by adding an ethanolic solution of 6-aminopurine to an aqueous solution of metal salts. This is followed by adding an ethanolic solution of theophylline and thiocyanate ion to give complexes with general formula [M (Tp)2 (Ad)X2] where Ad = 6-aminopurine, Tp = theophylline, X = thiocyanate ion and  M = Co (II), Ni (II),Cu (II), Zn (II) and Cd (II). The resulting products were found to be crystalline which have characterized using UV-Visible spectroscopic properties and Infrared spectra. Elemental analyses were performed using (C, H, N) and atomic absorption technique. The magnetic susceptibility and the conductivity were also measured. The present results suggested that the adenine as bidentate is coordinated with metal ions through the two nitrogen atoms N3 and N9. The theophylline as monodentat is coordinated with metal ions through the nitrogen atom N9. Thiocyanate ions are coordinated through the sulfur atom.

 
 
 
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Title: Strength behaviour of fibre reinforced polymer strengthened beam
Author (s): Pannirselvam N., Nagaradjane V. and K. Chandramouli

Abstract:

Strengthening of structures using fibre reinforced polymer (FRP) shows better promise for extending the life span of structures. The advantages of using FRP include light weight, ease of installation, minimal labour costs and site constraints, high strength-to-weight and durability. The objective of this work is to evaluate the structural behaviour of reinforced concrete beams with externally bonded FRP reinforcement. Beams bonded with four different types of Glass Fibre Reinforced Polymer (GFRP) having 3.50mm thickness were used. Totally five rectangular beams of 3 m length were cast. One beam was used as reference beam and the remaining beams were provided with GFRP laminates on their soffit. The variable considered for the study is type of GFRP laminate. The study parameters of this investigation included first crack load, service load, yield load, ultimate load, first crack deflection, service deflection, yield deflection, ultimate deflection, crack width, deflection ductility, energy ductility and the associated failure modes of the test beams. The performance of FRP plated beams was compared with that of unplated beams. The test results show that the beams strengthened with GFRP laminates exhibit better performance.

 
 
 
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Title: SAR signal processing algorithms
Author (s): Navneet Agrawal and K. Venugopalan

Abstract:

In space borne SAR systems some form of data compression is required to reduce the bandwidth of the downlink channel. In the present paper we have represented the complex SAR raw data with amplitude-phase (AP) and then applied the devised algorithm. It is observed that the phase information of the compressed data is preserved to the great extent. The quality of the reconstructed data is compared in terms of the important performance evaluation parameters like signal to noise ratio (SNR), standard deviation of the phase (PSD), mean phase error (MPE) and the compression ratio (CR). The amplitude-phase algorithm is compared with that of Block Adaptive Quantization (BAQ) algorithm. The evaluation procedure is carried out in two domains, raw data domain and image domain. Numerical experiments were carried out using ERS-2 satellite data supplied by European Space Agency (ESA) showing that amplitude-phase algorithm provides us with more Compression Ratio (CR) choices than BAQ and for certain CR, AP algorithm provides at least one choice whose performance is better than or equal to that of BAQ. These two algorithms neither affect spatial resolution nor generate geometric distortion. Both of them have only a little effect on radiometric resolution.

 
 
 
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Title: An investigation on the effect of incorporation of granite and marble wastes in the production of bricks
Author (s): S. Dhanapandian and B. Gnanavel
Abstract:

Sawing and polishing process of granite and marble industry generates large amount of wastes, which can seriously pollute and damage the environment. Therefore, this work intends to study the suitability of incorporation of granite and marble wastes in brick products. Samples of clay, industrial brick (fired) and wastes were collected from companies located in Salem District, Tamilnadu, India. Fired industrial brick was characterized by using FTIR and Mossbauer spectroscopic techniques. Secondly, several technological tests were conducted in order to evaluate the suitability of incorporation of wastes in brick production. The results showed that granite and marble waste can be added to an industrial clay mixture, already in use in the production of bricks with no major sacrifice on the properties of the final product.

 
 
 
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Title: Straw bale construction as an economic environmental building alternative- A case study
Author (s): Garas G., Allam M. and El Dessuky R.

Abstract:

Around four million tons of rice straw- (an agricultural residue)- is produced in Egypt annually. A great percentage of this amount is disposed of by burning causing high degrees of environmental pollution known as the Black Cloud that causes seriously chronic chest diseases to the great population of Egypt. This paper explores the different architectural styles of straw bale construction worldwide, with an aim to reach an economic environmentally adapted system for wide application of straw bale construction in Egypt. The paper presents an economical comparison between a load bearing wall unit built with locally produced rice straw bales and a traditional load bearing wall unit built with cement bricks. A direct cost saving that reaches about 40% of the total construction cost is achieved, in addition to the indirect cost saving in energy consumption and thermal insulation.

 
 
 
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Title: Environmental implications of unhygienic operation of a city abattoir in Akure, Western Nigeria
Author (s): A. O. Akinro, I. B. Ologunagba and Olotu Yahaya

Abstract:

Slaughterhouse wastewater has a complex composition and is very harmful to the environment. An effluent of a major city abattoir in Nigeria was studied for possible pollutants and effects of such pollutants on the environment. Findings showed that water samples were contaminated with E. coli and other enteric bacteria. The presence of coliform staphylococcus aures indicated the presence of microorganisms which are associated with water borne disease. Recommendations were made to ensure maintenance of good environmental condition in the city abattoirs particularly in the developing countries.

 
 
 
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Title: Prediction of pressure drop of refrigerants for two-phase flow inside a horizontal tube using CFD analysis
Author (s): P. Bhramara, K. V. Sharma and T. K. K. Reddy

Abstract:

Two phase flow in a horizontal tube has widespread applications, particularly in the condensers of refrigeration and air conditioning systems.  Pressure drop prediction is especially important for condensers because the local condensing temperature is a function of local pressure, affecting the mean temperature difference in the heat exchanger. In the present analysis, the two phase flow is treated as a single phase pseudo fluid with average properties of liquid and vapor using homogeneous model. CFD analysis of two phase flow of refrigerants inside a smooth horizontal tube is carried out under adiabatic conditions using commercial CFD software, FLUENT for different mass fluxes ranging from 100 to 1000kg/m2s and at different saturation temperatures of 400C, 500C and 600C. The values of pressure drop obtained from the simulations for refrigerants, R22, R134a and R407C are compared with correlations and experimental data available in literature.

 
 
 
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Title: The performance and emissions of a variable compression ratio diesel engine fuelled with bio-diesel from cotton seed oil
Author (s): R. Anand, G. R. Kannan, K. Rajasekhar Reddy and S. Velmathi

Abstract:

A methyl ester of cottonseed oil was prepared and blended with diesel in four different compositions varying from 5% to 20% in steps of 5%. Tests were conducted in a single cylinder variable compression ratio diesel engine at a constant speed of 1500 rpm. Highest brake thermal efficiency and lowest specific fuel consumption were observed for 5% biodiesel blend for compression ratio of 15 and 17 and 20% biodiesel blend for compression ratio of 19. The 20% biodiesel blend at a compression ratio of 17 had maximum nitric oxide emission as 205 ppm, while it was 155 ppm for diesel. Substantial reduction in Carbon monoxide emissions and smoke in the full range of compression ratio and loads was observed. Improved heat release characteristics were observed for the prepared biodiesels. The results reveal that the biodiesels can be used safely without any modification to the engine.

 
 
 
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Title: Short term load forecasting using artificial neural network- A comparison with genetic algorithm implementation
Author (s): Pradeepta Kumar Sarangi, Nanhay Singh, R. K. Chauhan and Raghuraj Singh

Abstract:

Load forecasting is an important component for efficient energy management system. Precise load forecasting helps the electric utility to make unit commitment decisions, reduce spinning reserve capacity and schedule device maintenance plan properly. Besides playing a key role in reducing the generation cost, it is also essential to the reliability of power systems. The system operators use the load forecasting result as a basis of off-line network analysis to determine if the system might be vulnerable. If so, corrective actions should be prepared, such as load shedding, power purchases and bringing peaking units on line. Some data mining algorithms play the greater role to predict the load forecasting. This research work examines and analyzes the use of artificial neural networks (ANN) and genetic algorithm (GA) as forecasting tools for predicting the load demand for three days ahead and comparing the results. Specifically, the ability of neural network (NN) models and genetic algorithm based neural networks (GA-NN) models to predict future electricity load demand is tested by implementing two different techniques such as back propagation algorithm and genetic algorithm based back propagation algorithm (GA-BPN).

 
 
 
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