Open Access Short Research Article

Effects of Chemical Admixture on Flow and Strength Properties of Calcined Clay Used as a Supplementary Cementitious Material

Mark Bediako, John Tristan Kevern

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/BJAST/2016/22905

Well-proportioned cement-based materials create durable, long-lasting infrastructure which benefit society. However lack of knowledge, availability, and interest result in many West African, Asia, and South American countries using natural or modified pozzolans without chemical admixtures. This study investigated powdered waste clay brick as a pozzolanic supplementary cementitious material (SCM). The calcined clay material was used to replace cement by weight at 10%, 20%, 30% and 40%. Consistent flow was achieved using a polycarboxylate high range water reducing admixture (HRWR). The results indicate that the application of HRWR increased the flow of calcined clay and Portland cement mortar mixtures. The maximum strength obtained for mixtures between Portland cement and calcined clay mortars was 30% replacement of cement by the calcined clay product. The study showed that a well-proportioned mortar mixture could reduce Portland cement content and CO2 significantly without compromising the strength and flow properties of the original mixture.

 

Open Access Original Research Article

Analysis of Performance in Release of Non-metallic Minerals’ Pollutants in Iran by Non-parametric Directional Distance Output Function Model

Siamak Bagherian

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/BJAST/2016/21619

In this study, the environmental aspects of nonmetallic mineral industries have been evaluated and the amount of pollutants and greenhouse gases from energy sources consumption has been calculated in all the subfields. The results demonstrate that the cement, lime and plaster having the utmost share of the spread of the carbon dioxide (CO2), involve the maximum share of the social costs. In this research, the technical performance of the mentioned industries has been calculated applying Slacks Based Measure (SBM) approach and the competent industries are specified. However the Directional Distance Output Function reveals that none of them are competent.

 

Open Access Original Research Article

Drying Rate of Selected Varieties of Cassava at Different Times of Harvest- A Response Surface Study

A. N. Agiriga, M. O. Iwe

Current Journal of Applied Science and Technology, Page 1-12
DOI: 10.9734/BJAST/2016/16794

Aims: To process cassava varieties-TME 419, TMS 30572 and TMS 98/0505 at different harvesting regimes by shredding with three shredding apertures-3 mm, 6 mm and 10 mm of a motorized cassava shredding machine and determine their drying rate.

Study Design: Cassava varieties were harvested at three months interval- 10, 13 and 16 months. They were shredded at each harvesting regime. A faced central composite design (k=4) was employed to study the linear, interactive and quadratic effects of the independent experimental variables- temperature, shred diameter, time of drying and time of harvesting on drying rate.

Place and Duration of Study: Cassava tubers were obtained from National Research Institute, Umudike, Abia State. Shredding was done at the Engineering workshop of National Research Institute, Umudike.

Methodology: Sixty nine (69) experimental runs were generated. Center points were replicated nine times, corner and star points were not replicated, data obtained were subjected to response surface analysis and Analysis of variance.

Results: Drying rate of the cassava shreds ranged from 0.000248 g/sec (TMS 30572,5400sec, 3 mm,100ºC) to 0.001063 g/sec (TMS 30572,5400 sec,10 mm,100ºC) at the 10tmonth;  0.000173 g/sec (TMS 30572,3600sec,6 mm,80ºC) to 0.000958 g/sec (TMS 98/0505,1800 sec, 3 mm,100ºC) at the 13th month and 0.00004 g/sec (TME 419,3600 sec, 6 mm, 80ºC) to 0.000336 g/sec (TMS 30572,1800 sec,10 mm,100ºC) at the 16th month. Linear and quadratic effects of time of drying had significant effect on the drying rate of TME 419; interaction between shred diameter and time of drying had significant effect on the drying rate of TMS 30572. Linear and quadratic effects of time of drying and interaction between shred diameter and time of drying had significant effect on the drying rate of TMS 98/0505.

Conclusion: Drying rate increased with shred diameter and temperature and reduced with reduction in shredding aperture.

Open Access Original Research Article

Atomic Absorption Spectrometric Determination of Some Heavy Metals from the Leaves of Moringa stenopetala Grown in Gamo Gofa Zone, Ethiopia

Ali Mohammed Yimer, Masood Akhtar Khan

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/BJAST/2016/17726

The plant Moringa (Moringa stenopetala), eaten as a vegetable, is a deciduous plant cultivated in the southern part of Ethiopia. It is indigenous to Ethiopia, distributed in the lowland ecology of the country. The present study was conducted with the objective of analyzing some trace metallic contents (Fe, Cr, Pb and Cu) in the leaves of Moringa plant and to identify their levels. The work was investigated based on samples collected from Arba Minch area, Gamo Gofa administrative zone. Atomic Absorption Spectrometry (AAS) was used to analyze the mentioned trace metals in this plant. The results showed: Fe, 1.18 mg/kg; Cr, 0.44 mg/kg; Cu, 0.67 mg/kg; Pb, 0.63 mg/kg. Thus, out of the four analyzed trace metals, Fe was found in larger amount compared to others and Cr was the smallest.

 

Open Access Original Research Article

Influence of Time of Harvest and Variety on the Pasting Properties of Starch from Three Cassava Varieties- A Response Surface Analysis

A. N. Agiriga, M. O. Iwe

Current Journal of Applied Science and Technology, Page 1-14
DOI: 10.9734/BJAST/2016/16792

Aims: Three cassava varieties TME 419, TMS 30572 and TMS 98/0505 were harvested at three months interval from maturity- 10, 13 and 16months. The aim was to optimize and determine the influence of experimental variables – time of harvest and cassava variety on their pasting properties.

Study Design: Starch was isolated from the cassava varieties at each harvesting regime and their pasting properties were determined using Rapid Visco Analyser.

Place and Duration of Study: Cassava tubers were obtained from National Research Institute, Umudike Abia State, starch was isolated at the Biochemistry Laboratory of National Research Institute, Umudike and the pasting work was done at Central Laboratory of the University of Ibadan, Oyo State.

Methodology: Sixteen experimental runs were generated. Center point was replicated seven times. Star and corner points were not replicated. Data obtained were subjected to response surface analysis. Optimization was done using optimization toolbox of Matlab r2012a software.

Results: Peak viscosity ranged between 5946RVU (TMS 98/0505-16 months) and 7327RVU (TME 419-13 months). Trough ranged between 2200RVU (TMS 30572-13 months) and 3463RVU (TMS 30572-10 months), Breakdown between 2878RVU(TMS 98/0505-16 months) and 4689RVU(TME 419-13 months). Final viscosity ranged from 3068RVU (TME 419-16 months) to 4154RVU (TMS 30572- 10 months). Setback ranged from 522RVU (TME 419-16months) and 1462RVU (TME 419-13months). Pasting temperature ranged between 75.05°C (TMS 30572- 16months) and 78.78°C (TMS 98/0505-10 months). Peak time ranged from 3.80 min (TMS 30572-13months) to 4.47 min (TME 419-10months).Variety and time of harvesting significantly (P=0.05) affected the pasting properties of starch from the cassava varieties. Optimization gave the minimum and maximum values of pasting parameters obtainable.

Conclusion: Variety and time of harvesting significantly affected the pasting properties of starch from the cassava varieties.

Open Access Original Research Article

Development of Rainfall Empirical Models for Osun Watershed, Nigeria

J. J. Musa, M. A. Abubakar

Current Journal of Applied Science and Technology, Page 1-11
DOI: 10.9734/BJAST/2016/21473

The aim of this study was to conduct a sequential detection for the possible trends in seasonal rainfall data series using various statistical packages. Farmers in Osun basin lack adequate planning with respect to agricultural activities for its maximum productivity as rainfall trends are often cited as one of the causes of socio-economic problems such as food insecurity. The available rainfall records provide information on monthly basis as obtainable from other meteorological stations nationwide. Rainfall records from 1980 to 2009 which were most consistent required for the development of rainfall models were used. A time series analysis was used to develop various models. The volume of rainfall within the study location was observed to fluctuate with December having the lowest amount of rainfall of 1.10 mm. The average rainfall was observed to be on the increase from the month of February through to the month of November with the highest amount of rainfall recorded in the month of September with an average rainfall of 556.60 mm. The polynomial equation was used to develop a best line of fit of y = 1.4227x3 – 29.502x2 + 154.72x + 9.2348 with a R Square value of 0.7541. A double maxima of June and September was observed while April which is used to be the beginning of the raining season tends. October which used to be the beginning of dry season was also observed to tend towards raining month. The linear, exponential growth and s-curve equation models of the forms Yt = 16141 + 84.5t; yt = 15557.6 * (1.00676t); and yt = 105/(5.77969+3.26815 (0.6591t)) were developed respectively. The data set were further decomposed and it was observed that there was a seasonal effect. The seasonal indices show the average downward movement within the first 3 months and the last 2 months of the season and average upward movements from the 4th to the 10th month. In conclusion the Linear model from this study proved to be the best for predicting rainfall events for the Osun watershed. It is therefore recommended that the Linear model be used to predict rainfall for the Osun watershed.

 

Open Access Original Research Article

Steel Work Design and Analysis of a Mobile Floor Crane

Okolie Paul Chukwulozie, Obika Echezona Nnaemeka, Azaka Onyemazuwa Andrew, Sinebe Jude Ebieladoh

Current Journal of Applied Science and Technology, Page 1-9
DOI: 10.9734/BJAST/2016/23079

The transportation of heavy machine parts and equipment within and outside the workshop has been a source of concern and needs urgent attention because of the hazard it exhibits. This negative effect on the health of engineers, led to the invention of the floor jib crane but research shows that contemporary designs of floor jib crane fail over time when these static load is left on it for a prolonged period of time. This project is centered on the design and fabrication of a mobile floor crane equipped with a facility to lock the load at any level as a special feature, to tackle the issue of failure due to static load. The mobile crane is designed to bear a maximum load of about 1000 kg, with a counter weight of 2.6 KN which gave the crane a 3.034 factor of safety. The materials employed are; sheet metals, angular iron, bolts, nuts, metal rollers etc. The fabrication processes involved drawing, marking out, cutting, filling, welding and assembling. For permanent joints, the arc welding process was employed. As indicated earlier, the mobile floor crane gains its significance in the transportation of heavy machine parts within and outside the workshop. It can also be used to load and unload machine parts on trucks.

 

Open Access Original Research Article

Callus Cell Proliferation and Explants Regeneration Using Broccoli Shoot Tip in vitro Culture: Biochemical and Antioxidant Properties

A. B. M. Sharif Hossain, Imdadul Haq, Mohammed Saad Aleissa, Nasir Adam Ibrahim, Kamaludin Bin Rashid

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/22665

Significance of the Study: Nowadays cell or tissue culture has been successfully performed using different types of species like fruit, vegetable, ornamental and forest plant. Millions of explants can be produced by tissue or cell culture per year in any plant production industry. Combination of 6-Benzylaminopurine (BAP) and other plant growth regulators like 1-Naphthaleneacetic acid (NAA) or Indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) was used in the most of the research in tissue culture.

Aims: The study was carried out to investigate the root, callus, shoot and leaf proliferation from the shoot tip in vitro culture using different IBA and BAP concentration.

Methodology: Shoot tip slice was used to culture in the MS (Murashige and Skoog) media. Different IBA and BAP (0, 0.25, 0.50, 1.0, 1.50, 2.0 2.5, 3.0 and 3.5 mg/l) concentrations in combination with MS media were used.

Results: The highest number (7.4) of shoot proliferation was observed in the concentration of IBA 0.25+BAP 2.5 mg/l combination. The maximum root proliferation was found in the concentration of IBA 0.25+ BAP 1.5. However, callus formation was observed better at the concentration of BAP 1-3.5 and IBA 1-3.5 mg/l combination than other combination of concentrations. The 2,2-diphenyl-2-picrylhydarzyl (DPPH) free radical scavenging potential was higher (70.1%) in leaves extract than in callus extracts (46.3%) at the concentration of 10 mg/ml. Besides, both extracts had lower DPPH free radical scavenging activity compared to the positive control, vitamin C and BHT.

Conclusion: The present results conclude that it is better to use the combination of the IBA and BAP concentration to produce root, shoot, leaf and callus cell proliferation in broccoli.

Open Access Original Research Article

Effect of Throttling Variation on the Performance of Vapour Compression Refrigeration System

P. K. Farayibi, T. S. Mogaji, T. J. Erinle

Current Journal of Applied Science and Technology, Page 1-10
DOI: 10.9734/BJAST/2016/23086

In this paper, the effect of throttling variation on the performance of vapour compression refrigeration system using R134a refrigerant as working fluid was investigated and reported. The investigation was carried out using a refrigeration test rig with capillary line as throttling device which was split into three capillary lines of the same length under a room temperature condition of 29 – 32°C. The test rig was equipped with four sigma manifold gauges which were installed at the inlet and exit of the condensing and evaporating units to take the pressure and temperature readings of the working fluid. Experimental trials were conducted by taking the pressure-temperature readings when one-, two- and all the three capillary lines were engaged for the throttling process. The enthalpy condition of the refrigerant at the inlet and exit of the condenser and evaporator were obtained from a standard COOLPACK saturation table. The performance of the refrigeration system was analysed based on the experimental data. Results showed that the temperature difference between the inlet and exit of the evaporating unit was found to increase from 8.66°C to 24.65°C, refrigerating effect increases from 141.2 kJ/kg to 144.6 kJ/kg while work done by compressor decreases from 24.8 kJ/kg to 21.6 kJ/kg as the number of capillary lines employed increases from one to three. The coefficient of performance of the system was found to increase from 5.69±0.04 to 6.71±0.04 which was 17.9% and 7.5% higher than the COP of the system if only one- and two capillary lines were respectively employed for the throttling process. The system behaviour has been attributed to earlier development of the two-phase mixture from the saturated liquid as the number of capillary line increases, thus improving the system performance.

 

Open Access Review Article

Hybrid Methods for Credit Card Fraud Detection Using K-means Clustering with Hidden Markov Model and Multilayer Perceptron Algorithm

Stephen Gbenga Fashoto, Olumide Owolabi, Oluwafunmito Adeleye, Joshua Wandera

Current Journal of Applied Science and Technology, Page 1-11
DOI: 10.9734/BJAST/2016/21603

The use of credit cards is fast becoming the most efficient and stress-free way of purchasing goods and services; as it can be used both physically and online. Hence, it has become imperative that we find a solution to the problem of credit card information security and also a method to detect fraudulent credit card transactions. Over the years, a number of Data Mining techniques have been applied in the area of credit card fraud detection. The focus of this paper is to model a fraud detection system that would attempt to maximally detect credit card fraud by generating clusters and analyzing the clusters generated by the dataset for anomalies. The major objective of this study is to compare the performance of two hybrid approaches in terms of the detection accuracy. We employed hybrid methods using the K-means Clustering algorithm with Multilayer Perceptron (MLP) and the Hidden Markov Model (HMM) for this study. Our tests revealed that the detection accuracy of “MLP with K-means Clustering” is higher than the “HMM with K-means Clustering” for 80% percentage split but the reverse is the case when the “MLP with K-means Clustering” is compared with the “HMM with K-means Clustering” for 10 fold cross-validation but the accuracy is the same in the two hybrid methods for percentage split of 66%. More extensive testing with much larger datasets is however required to validate theses results.