|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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. |
|
|
|
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). |
|
|
|
|
|
|
|
|