LAUTECH Journal of Engineering and Technology (LAUJET)
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EFFECT OF SODIUM CHLORIDE SALT ON THE RHEOLOGICAL PROPERTIES OF SUNFLOWER OIL-IN-WATER EMULSION STABILIZED BY GELATINIZED BAMBARA GROUNDNUT FLOUR
Get PDF The influence of sodium chloride salt (NaCl) concentrations (0 – 300mM) on the rheological properties of sunflower oil-in-water emulsions (40 w/w%) stabilized by 7 w/w% gelatinized bambara groundnut flour (BGNF) was investigated. Rheological characterizations of the emulsions were carried out using a shear rate controlled rheometer. Emulsions with and without NaCl were thixotropic, pseudoplastic and viscoelastic fluids. The mean hysteresis loop area, consistency coefficient and recoverable strain were in the range 389.90 – 771.50 Pas-1, 13.61 – 44.87 Pasn and 10.82 – 46.15 % respectively. NaCl significantly affected (p < 0.05) rheological properties of BGNF-stabilized emulsion. Increased NaCl in the emulsion decreased extent of thixotropy, pseudoplasticity and viscoelasticity of BGNF-stabilized emulsions. The results indicated that the rheological properties of BGNF-stabilized emulsion can be controlled and manipulated using NaCl. The result provided the information necessary to understand the influence of NaCl on the rheological properties of BGNF-stabilized emulsions for product and process development
DETERMINATION OF SOME ENGINEERING PROPERTIES OF CASSAVA TUBERS GROWN IN NORTHERN NIGERIA
No full textSeveral cassava processing operations have been mechanized successfully, but cassava peeling is still largely carried out manually; however, in this work some selected engineering properties of 5 cassava varieties mostly grown in northern part of Nigeria were determined to provide basic data for the design of cassava peeling machine. These properties include thickness of the peel, the length, and axial dimensions - major, intermediate and minor diameter and the Strength of peel (peeling force), and Bioyield(breaking force). The average length of the tubers measured are in the range of 15.4 – 68.51 cm while the maximum and minimum thickness of the peel are 6.01 and 0.54 mm respectively. The peel reduces in thickness from the radicle towards the apex and the larger the diameter of the tuber, the thicker the peCassava peelingel. The highest and lowest values of the peeling force are 2248 kN/m2 and 401 kN/m2respectively. It was observed that the peeling force value increases and reduces along the length of the tuber. Also the peeling force reduces with time after harvest and has the highest value at 24 hours after harvest. This could be due to the deterioration of the tuber with time. The major, minor and intermediate diameters of the tubers determined are in the range of 3.00 –10.35 cm, 2.15 – 10.05 cm and 0.87 – 6.04 cm respectively. The maximum bioyield force was 3880 kN/m2 and minimum was 769.3 kN/m2. All these are important in the design of a cassava peeling machine
AN EVALUATION OF THE IMPACT OF MOTIVATION ON EMPLOYEE PERFORMANCE: A STUDY OF THE CIVIL SERVICE OF OSUN STATE, NIGERIA
No full textThis paper accessed employees’ level of motivation vis-a-vis their level of performance. The objective was to ascertain the nature of the relationship between the two variables within the context of prevailing conditions of work in the public service. The study sample was up of 580 randomly selected workers of the Osun State Civil Service and 345 randomly selected clients of the government establishments. Data were collected through two questionnaires and analyzed using Pearson Product Moment Correlation Coefficient. Results showed that there was no significant relationship between motivation and performance of the workers. It was concluded that lack of necessary requirements in the work environment prevented the intrinsic motivation of the workers from being translation into higher performance levels
THE DESIGN OF AN UNDERGROUND STORAGE SYSTEM FOR RAINWATER HARVESTING IN IBADAN METROPOLIS, NIGERIA
No full textWith vastly increasing population concentration in urban areas of Nigeria, water availability has already caused an intractable problem, whose solution has to involve harnessing and storing water from all sources for continual use. This work is on designing a rainwater storage system for use in individual homes in Ibadan, Oyo State, Nigeria.
Inputs to the design are rainfall data for 1980 to 2003 from which the theoretical rainwater quantity harvestable each month was calculated. Water demand per household of eight persons was computed for use in the design. Platting the graphs of the cumulative mean monthly rainfall and of uniform monthly water demand, the minimum capacity of water storage tank to meet the demand was obtained.
The size of the storage tank and various forces acting on it were found to depend on the roof type and roof plan area
AN mAGRICULTURE FRAMEWORK FOR AGRICULTURE INFORMATION SERVICES DELIVERY
Get PDFAgriculture is an information intensive industry that is spatial in nature. For farmers to thrive, they must be generalists who are well versed in the latest farming technologies. Thus, farmers need to be well informed on the best agricultural practices, prime farming operation techniques, optimum methods of management, prevailing post harvest operations and transactions and so on. However, Nigerian and African agriculture in general is disadvantaged owing to factors that include: poor access to agriculture-related information, deficits in physical infrastructure, high transactional costs, digital divides, low literacy level, problems with availability of agricultural inputs to mention but a few. In this paper, we present an mAgriculture framework for agricultural information services delivery using the communication channels available on a feature phone. Features phones are easy to use and are increasingly able to bypass the barriers of illiteracy and affordability, and they provide access to a wide range of very useful services, such as transferring money, checking market prices, gathering weather information, obtaining personal agricultural extension and other professional advice. The three basic communication channels of feature phones employed by the developed framework are: voice, short message service (SMS) and Unstructured Supplementary Service Data (USSD) with the intent of providing a platform where farmers’ need of agriculture information could be met
IMPROVED INTRINSIC STRESS MODELS FOR THIN FILMS BASED ON SURFACE STRESS
Get PDFStudy of stress evolution in thin films has been an area of rigorous research for the past few decades. In spite of these research efforts, understanding stress generation and relaxation remains incomplete. In this study, a modified surface stress based approach for modeling intrinsic stresses in thin film using dome-shaped islands and hexagonal shaped grains is proposed. Equations that describe stress evolution at the precoalescence, coalescence and postcoalescence growth stages were derived. The results of the models were then compared to some previous models and validated with experimentally obtained values for copper and silver films at various growth stages. For Cu films deposited on silicon substrates, intrinsic stresses of -200, 140 to 230 and -260 to -80 MPa were obtained for precoalescence, coalescence and steady state postcoalescence stages, respectively while the current models gave -261, 102 and -115MPa. For continuous film, the current model gave -115 MPa which is comparable to -140 MPa obtained from an experimental study conducted on Cu thin films. Furthermore, parametric studies showed that the directions of growth for both intrinsic and steady state stress are converse. Thus, the results obtained indicate that the current models are reliably and can be used for accurate stress prediction. The predictions of the current models are closer to the experimental values than any of the previous models
MECHANOCHEMISTRY: A GREEN SOLUTION IN CHEMICAL SYNTHESIS
Get PDFEfforts to encourage economic, environmentally and user friendly synthetic method has continued to gain general support of researchers and general society in recent time. Mechanochemistry is a key way that has proved to be safety conscious and hazard minimizing and control production/reaction methods. Mechanochemical synthesis can be described as an application of green chemistry which has as its aim the usage of chemical products and processes in such a way that it eliminates the use or generation of hazardous substances from its design, manufacture and use. This paper attempts to review the emerging principles and potentials of mechanochemistry as a green way to synthesis and cleaner production of chemical products without the use of which are toxic and are potentially harmful to human health and environment. Based on this work, researchers are encouraged to intensify efforts on improving mechanochemical based manufacturing technique
NEURAL NETWORK MODELING OF OIL YIELD FROM SHEAKERNELS IN A HYDRAULIC PRESS
No full textAn investigation on prediction of oil from shea kernels in a hydraulic press subject to process variables such as moisture content, pressing time, applied pressure, heating time and heating temperature was carried out. Artificial neural network (ANN) technique was applied using experimental data from a previous study. These data were then used for network training and testing. The back propagation technique was then used for establishing the network. The prediction accuracy of the neural network model was significantly improved compared to statistical model. (R=0.96)
Key words: Oil expression, yield, neural network, prediction
ANALYTICAL SOLUTION OF THE RELATIVISTIC KLEIN-GORDON WAVE EQUATION
Get PDFIn this study, the solution to Klein-Gordon equations with focus on analytical methods is discussed. The analytical methods used in this research are the Variational Iteration Method (VIM) developed by Ji-Huan He, Adomian Decomposition Method (ADM) by Adomian and New Iterative Method (NIM) developed by Daftardar Gejji and Jafari. The modified Adomian Decomposition method by Wazwaz was used to solve the linear inhomogeneous and nonlinear Klein-Gordon equations to accelerate the convergence of the solution and minimizes the size of calculation while still maintaining high accuracy of the analytical solution. All the problems considered yield the exact solutions with few iterations. The solutions obtained were compared with the exact solution and the solutions obtained by other existing methods. The solutions obtained by the three methods yield the same results and all the problems considered show that the Variational Iteration Method, Adomian Decomposition Method and New Iterative Method are very powerful and potent in solving Klein-Gordon equations and can be used to obtain closed form solutions of linear and nonlinear differential equations (ordinary and partial)
FINGERPRINT BASED STUDENT ATTENDANCE MANAGEMENT SYSTEM WITH AUTOMATIC EXCEL COMPUTATION
Get PDFFingerprint is considered to be the best and most widely used biometrics recognition and verification pattern due its uniqueness for every individual. This study focused on the development of a fingerprint students’ attendance system carried out to curb the problems associated with manual methods of taking students attendance in institutions. The design was carried out using appropriate mathematical model, formulae and block diagram representation while Proteus software simulator was used to simulate functionality of the designed circuit. An attendance algorithm was developed and implemented using coolTerm software and Excel spreadsheet. The system was tested using 15 students’ fingerprints which involves enrollment, authentication and report generation processes. Each student was enrolled with a unique identification. During verification and attendance capture at different times, the system exhibits extremely low (0%) False Acceptance Rate (FAR), extremely high (100%) True Accept Rate (TAR) and extremely low (0%) False Reject Rate (FRR). This study has established the effectiveness of students attendance capture using fingerprint as a more secure, credible and error free to impersonation and buddy punching as associated with the existing manual-paper based system