Heavy metal pollution around Itakpe mine, Kogi State, Nigeria
July 2012
The removal of large quantities of overburden through mining has resulted in the pollution of various ecosystems. Soil pollution around the Itakpe mine in Kogi State, Nigeria was studied through the determination of heavy metal concentration and chemical speciation of the metals cadmium (Cd), copper (Cu), magnesium (Mg), nickel (Ni), lead (Pb) and zinc (Zn) in soil using Flame...
Anti-vortex structures at hydropower dams
July 2012
Vortex formation due to power generation at hydropower dams could cause serious problems, and eliminating or reduction in its strength is one of the dam designer and manager duties. Therefore, the design and use of anti-vortex structures is usual. Design of an anti-vortex structure for each project is unique and it is therefore necessary to have knowledge about the performance of each one. In the present...
Assesment of heavy metals contamination in groundwater: A case study of central industrial district in Ilorin, Kwara State, Nigeria
July 2012
Heavy metals were investigated in groundwater in the central industrial district of Ilorin, Kwara State, Nigeria. Water and sediment samples from 8 wells in the district and 2 away from the district (control) were analysed to assess the suitability of the water for human consumption and domestication purposes. The measured heavy metals concentrations exceeded the World Heaith Organization (WHO) standard...
New exact Jacobi elliptic solutions for the generalized time-dependent variable coefficients KdV- mKdV equation
July 2012
In this article, we use the improved general mapping deformation method based on the generalized Jacobi elliptic functions expansion method with computerized symbolic computation to construct more new exact solutions of a generalized time-dependent variable coefficients KdV- mKdV equation. As a result, new generalized Jacobi elliptic function-like solutions, soliton-like solutions and trigonometric...
Several new iterative methods for solving nonlinear algebraic equations incorporating homotopy perturbation method (HPM)
July 2012
In this paper, several new iterative methods for solving nonlinear algebraic equations are presented. The iterative formulas are based on the He's homotopy perturbation method (HPM). It is shown that the new methods lead to eight algorithms which are of fifth, seventh, tenth and fourteenth order convergence. These methods result in real or complex simple roots of certain nonlinear equations. The merit of...
Daily averages of solar radiation measured at Iju, Nigeria in 2008
July 2012
This work presents one year data of global solar radiation flux measured at a humid tropical location in West Africa (Iju, Nigeria; 7.15°N, 5.12°E) for the period 1st January to 31st December, 2008. The collected raw data were analyzed using Origin software and Excel spreadsheet to determine the daily means, daily minima and maxima for the period under consideration. The daily mean for the year...
Measurement of sediment oxygen demand for modeling the dissolved oxygen distribution in a Subalpine lake
July 2012
Sediment oxygen demand (SOD) is believed to be an important process affecting dissolved oxygen (DO) concentrations and has become an integral part of modeling dissolved oxygen (DO) in surface water bodies. Because no SOD data are measured at specific study sites, it is common for researchers to take SOD values from the literature for use in DO modeling. This paper focuses on an approach for measuring sediment...
Secure quantum dialogue using entanglement swapping
July 2012
In this study, a protocol for secure quantum dialogue using entanglement swapping was proposed. The protocol employs two independent communication channels, a classical channel and a quantum channel. In this scheme, the legitimate communicators Alice and Bob can pass the authentication by the classical trusted channel. Afterwards, a quantum channel sequence is provided for them, on which Alice and Bob...
Fuzzy logic in candidate-well selection for hydraulic fracturing in oil and gas wells: A critical review
July 2012
During the last two decades, Fuzzy Logic (FL) Systems have been increasingly applied to the research area of petroleum engineering. Hydraulic Fracturing (HF) as an important discipline in this area and stimulation of oil and gas wells is an important tool for natural gas and oil exploitation, whose success relies on proper selection of target well and target formation. To date, however, no paper has attempted...
Improving the flow in pipelines by Cocos nucifera fiber waste
July 2012
In this study, fiber performance as drag reducing agent in aqueous media flow in pipeline was investigated. Use of fiber from the Cocos nucifera (coconut) to reduce friction in pipe flow is a new invention in the fluid transport technology. The use of coconut fiber in liquid pipelines can reduce operating costs which can have a...
Conjugate effects of heat and mass transfer of nanofluids over a nonlinear stretching sheet
July 2012
This study investigates theoretically the problem of free convection boundary layer flow of nanofluids over a non-linear stretching sheet. The model used for the nanofluid incorporates the effects of buoyancy parameter, the solutal buoyancy parameter and the power law velocity parameter, and found to have strong influence on the system. The resulting non-linear partial differential equations with...
Chemical and microbial investigation of drinking water sources from Kohat, Pakistan
July 2012
Safe drinking water is one of the basic human rights and essential need for healthy life. In Pakistan, the quality of drinking water is not being managed properly and various studies provide evidence that most of the drinking-water supplies are contaminated. In this study, 60 drinking water samples from both urban and rural areas of district Kohat were analyzed chemically and microbiologically, to find...
Effect of glue splotches on coloring
July 2012
Particleboard surfaces of 18 mm were coated with Scots pine (Pinus sylvestris L.), oriental beech (Fagus orientalis L.) and sessile oak (Quercus petraea L.), wood veneers, were splotched with urea formaldehyde (UF), polyvinyl acetate (PVAc), contact (rubber adhesive) and gluten glues. Then, these surfaces were colored with wood stains of aniline, chemical {(tannin) (C14H10O9) + potassium...
Seismic performance of structures with pre-bent strips as a damper
July 2012
In this study, a new type of structural damper in the form of braces based on pre-bent strips has been proposed. In designing the structures, parameters that support the safety of structures like base shear, acceleration and displacement are so important. To create safe conditions in structures some new technologies like vibration control and isolation have been considered. Vibration control has been studied...
Generation of surface optical vortices by evanescent Bessel beams
June 2012
We present that a set of high order Bessel beams when internally reflected at a dielectric/vacuum interface can create distinct evanescent light modes in each of which the intensity distribution is restricted to a sub-wavelength region near the interface outside the dielectric. We believe that this could really facilitate lateral optical manipulation of nano-particles and neutral atoms along the interface....
Mapping extensible markup language document with relational database management system
June 2012
The extensible markup language (XML) is designed for data representation with conciseness, generalization, and usability through the internet, however, this technology requires an appropriate medium for the storage of data. The approach, named XRecursive, is proposed to store and retrieve XML documents using relational database, which is applied to all internal nodes mapped by Schema-oblivious, and all the leaf...
Characterisation of impulse noise effects on space-time block-coded orthogonal frequency division multiplexing (OFDM) signal reception
June 2012
This correspondence presents the characterisation of impulse noise effects on the space-time block-coded orthogonal-frequency-division-multiplexing (STBC-OFDM) symbol reception, in which the conventional OFDM system is combined with the antenna-diversity/spatial-diversity in order to achieve the high data transmission rates. The weak impulse noise may be combated by the longer OFDM symbol duration, in which the total...
Variational iteration algorithm-II for solving linear and non-linear ODEs
June 2012
Variational iteration method is widely used for solving linear and non-linear ODE. In this paper, the variational iteration algorithm-II is constructed and some examples are given to show its simple solution procedure and high accuracy of the obtained results. Key words: Variational iteration method, series solution, ordinary differential equations.
Special type of three-phase oscillator using current gain control for amplitude stabilization
June 2012
The main aim of this work is to demonstrate the use of electronically controlled second-generation current conveyor in providing electronic control to the condition of oscillation (CO) of a new active RC sinusoidal oscillator. Electronic control of the CO, which is independently set and does not affect the oscillation frequency, is enabled by the use of an auxiliary amplitude control loop to regulate the amplitude and...
Design and performance of photovoltaic power system as a renewable energy source for residential in Khartoum
June 2012
This paper discussed the efficient system of sustainable renewable energy for domestic used and its total cost. The method of this paper was the collection of the basic data of solar radiation, wind speed and other required input data, and then hybrid optimization simulation model was developed using the electric renewable energy software hybridoptimization model of renewable energy (HOMER). Simulation model has...
Seasonal variations in groundwater quality: A statistical approach
June 2012
In this study, a descriptive statistical measure and a partial correlation analysis were applied to groundwater quality data set monitored in pre-monsoon and post-monsoon for three years to investigate seasonal variations of Central Ganga Plain in India. The variables were divided into two categories as “chemical property- HCO3, Cl, SO4, Na, K, Ca, and Mg” and “physical property- electrical...
Query expansion based on contextual meaning of the query terms
June 2012
In this paper, a new method for query expansion is proposed which expands the original query based on the contextual meaning of it. User provides the method with an original query and a set of relevant documents. The term space extracted from the relevant documents by the vector space model is transformed to a topic space by means of latent semantic analysis. The terms’ projections in the topic space are grouped...
A neural network approach for cumulative monthly rainfall time series forecasting tuned by roughness
June 2012
In this work a feed-forward neural networks (NN) based nonlinear autoregressive filter (NAR) approach for forecasting cumulative monthly rainfall time series is presented. The filter parameter adjustment is performed in accordance with time series roughness. This method has concordance with the long or short term stochastic dependence of the time series and the proposal is an on-line heuristic law to set the training...
Synthesis, characterization, theoretical calculations and biological studies of potassium trifluorothiocyanoborate (III)
June 2012
Synthesis, characterization, spectral and theoretical calculations of potassium trifluorothiocya noborate (III) (PTFTCB) has been studied. Potassium trifluorothiocyanoborate (III) was synthesized and characterized by IR, UV/VIS, 11B-NMR and mass spectrometer techniques. The structure of synthesized compound was optimized at the B3LYP/LANL2DZ level of theory and theoretical parameters such as structural data, molecular...
Studies on mass attenuation coefficients, effective atomic and electron numbers for Cd1-xZnxTe alloy at photon energies of 10 to 100 keV
June 2012
The physical parameters calculated using Full Potential Linear Muffin Tin Orbitales FP-LMTO method is satisfying. Using the photon mass attenuation coefficient obtained via XCOM data of Cd1-xZnxTe compound, the effective atomic number and the effective electron number were determined in the energy range of 10 to 100 keV. The effective atomic and electron numbers are linearly related and they also depend on the incoming...
East African rainfall seasonality based on modulated annual cycle (MAC)
June 2012
The spatial and temporal variability of East African rainfall seasonal cycle is investigated based on modulated annual cycle (MAC). Ensemble empirical mode decomposition (EEMD) is used to extract MAC from monthly data for the period 1900 to 2008. The MAC is given by year-to-year changes in annual and semi-annual components. Results show that MAC account for between 45 to 80% proportion of rainfall variability....
Synergetic performance of palm oil (Elaeis guineensis) and pine oil (Pinus sylvestris) as binders on foundry core strength
June 2012
Possibilities of foundry sand core binders made with combination of Elaeis guineensis andPinus sylvestris have been evaluated and the combine effect of these oils as binder were discussed. Core specimens made with Ota silica base sand bonded with 6% of cassava starch in admixed proportion of E. guineensis and P. sylvestris were tested for tensile, compressive strength...
Laminar boundary layer flow along a stretching cylinder embedded in a porous medium
June 2012
Laminar boundary layer flow of an incompressible viscous fluid along a stretching horizontal cylinder embedded in a porous medium is discussed. The governing system of partial differential equations is reduced to a system of ordinary differential equations. Mathematics has been used to solve such system after obtaining the missed initial conditions. The obtained results are compared with previously published results in...
Impact of frequency switching on the efficiency of a fully suspended active magnetic bearing system
June 2012
Due to the rising energy (and electricity) cost it is essential that an active magnetic bearing (AMB) system is operated as efficiently as possible. Frequency switching caused by an external source can cause an AMB system to operate at a higher than expected energy level and lower than expected efficiency. The purpose of this paper is therefore to investigate the impact of frequency switching (caused by an external...
Probing relation between solar activities and seismicity
June 2012
In this paper, we studied the relationship between sunspots numbers (SNs), solar 10.7 cm radio flux (SRF), solar irradiance (SI), solar proton events (SPEs) and local earthquakes. The location of the study is selected in Iran area and all earthquakes data chosen for M≥ 4 from 1970 to 2010. The study reveals the following conclusions: (i) The total number of local earthquakes in maximum years of solar activities is...
Effect of gamma irradiation on biophysical and protection properties of melanin
June 2012
Melanins are natural pigments distributed in living organisms and they are responsible for pigmentation of surface structure. In the present work, gel exclusion chromatography, spectrophotometric, and dielectric relaxation techniques were used to characterize DOPA melanin before and after irradiation with 60Co gamma rays in the range of 5 to 50 Gy. The results show that the studied melanin is composed of two...
Frictional resistance of coal dust fouled uniformly graded aggregates
June 2012
Large deposits of coal over vast expanse of lands attract mining companies, power stations and petrochemical companies and thus the development of coal towns with rail and road networks. High traffic volume of large quantities of coal across coal cities often result in the gradual accumulation of fine coal dust particles on road pavements, rail ballast and sleepers. The effect of coal dust on the Direct Shear...
Effect of zinc acetate concentration on the structural and optical properties of ZnO thin films deposited by Sol-Gel method
June 2012
The transparent Zinc Oxide (ZnO) thin films were deposited by multi-step sol-gel method and the effect of sol concentration on structural, morphological and optical properties were investigated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to characterize structures and morphologies of the as-deposited films. The crystallographic orientation of the ZnO films shows the preferred...
Control of a manipulator kinematics robotic arm on fuzzy cerebellar model articulation controller
June 2012
While in this paper, we present a model of fuzzy cerebellar cortex that puts together two sorts of learning: feedforward and predictive association founded on learning between granule cell ascending branch and parallel fiber inputs, and reinforcement learning with feedback error correction based on climbing fiber activity. To show the model's utility, we simulated the control of a robotic arm. Specification of the...
Natural lifts and the geodesic sprays for the spherical indicatrıces of the mannheim partner curves in
June 2012
In this paper, we investigated the natural lifts and curvatures of the spherical indicatrices of the Mannheim partner curves in . Firstly, it is shown that the Darboux vector of Mannheim curve and tangent vector of the Mannheim partners should be linearly dependent. Secondly, the relations among the geodesic curvatures and arc-lengths with respect to and of the fixed pole curve and the...
A new approach to technique for order-preference by similarity to ideal solution (TOPSIS) method for determining and ranking drought: A case study of Shiraz station
June 2012
In this research, using technique for order-preference by similarity to ideal solution (TOPSIS) index, drought phenomenon is determined and ranked. For this purpose, using 5 atmospheric elements including temperature, wind, precipitation days, annual precipitation, precipitation concentration index (PCI), droughts occurred in Shiraz station for 20-year statistical period (1983-2003) have been determined and ranked....
A multiresolution approach for color image inpainting using an efficient generalized expectation maximization (GEM) model
June 2012
In this paper, we present a novel expectation maximization (EM) algorithm for automatic color image inpainting using a new discrete multi scale directional sparse representation called the discrete shearlet transform (DST). It is now acknowledged that the traditional wavelets are not very effective when dealing the multi dimensional signals having distributed discontinuities such as edges. To achieve a more efficient...
Analysis of thermal efficiency of a passive solar water heater
June 2012
The analysis of thermal efficiency of a passive solar water heater is presented. The heater which has potential applications in agro-industries and homes, consisted of a single-glazed flat plate solar collector made up of an absorber plate and a transparent sheet of glass; water storage tanks and the stand. The absorber plate was made of mild steel which is a very good conductor of heat. Copper tube was used to form a...
Fabrication of 6 nm gap on silicon substrate for power-saving appliances
June 2012
We document a thermal oxidation process for the reproducible fabrication of 6-nm gaps on silicon-on-insulator (SOI) substrate. Nanogaps sizes of this dimension are implicated to eliminate contributions from double-layer capacitance in the dielectric sensing of proteins or nucleic acids. The method combines conventional photolithography and pattern-size reduction technique to create a desired-size gap. The gaps are...
Hydrological characterization of Mahd Ad Dahab Gold Mine, Saudi Arabia
June 2012
The present study focuses on the gold mining in Mahd Ad Dahab region of Saudi Arabia. The study aims at the integrated use of existing meteorological information with the drainage basin morphometry of the mine catchment for determining the preferential flow path for the mine contaminants. The study reveals that the actual mining area lies at the headwaters of two watersheds: Watershed A and Watershed B. The streams in...
Crystal structure of 2-[(2-(2-Hydroxyethylamino) ethylimino) methyl] phenol at 130K
June 2012
In this research, the 2-((2-(2-hydroxyethylamino) ethylimino) methyl) phenol (H2L) has been prepared with high yield via condensation of salicylaldehyde and 2-hydroxyethelamine. Crystal structure of H2L is determined at 130K. In the crystal structure of H2L, it is observed that there are two independent H2L-units. X-ray crystal structural analysis revealed that the H2L belonged to the...
Solvent extraction of copper, nickel and zinc by Cyanex 272
June 2012
Studies were conducted on the extraction of copper, nickel and zinc from their sulphate solutions using [bis (2,4,4- trimethylpentyl) phosphinic acid] (Cyanex 272, HA) as an extractant. Effect of various parameters, such as equilibrium pH, extractant concentration, sulphate and acetate ion concentration was investigated. The slope analysis method was used to determine the nature of extracted metal complexes. For the...
Various types of shear connectors in composite structures: A review
June 2012
In this paper, an attempt has been made to review various types of shear connector in composite structures. This review tries to identify the shear connectors that are most relevant to composite structures and reviews representative journal publications that are related to this topic. It attempts to cover all types of shear connector. The article concludes with a discussion of recent applications of shear connectors in...
The influence of relaxation with electromyography and Islamic prayer programs for female Muslim
June 2012
Chronic work-related stress can fray nerves, keep you up at night and contribute to significant and independent risk problems such as heart disease and depression. Particularly, chronic job strain can put both your physical and emotional health at risk. Muscle relaxation is a useful evidence based teaching and treatment approach for physical/remedial therapists. It can show unnecessary covert muscles co-contractions and...
Modeling and characterization of all possible triple pass EDFA configurations
May 2012
The main purpose of designing multi-stage erbium-doped fiber amplifiers (EDFAs) is to achieve higher gain and lower noise figure for long haul optical communication. Among the multi-stage EDFAs, triple pass EDFAs were chosen in this research. This paper presents all possible triple pass EDFA configurations. The well-established one-stage mathematical models were modified to design two-stage and...
An estimation of time-varying signal frequency using recent finite observations
May 2012
For estimating a time-varying signal frequency, an alternative estimator with a finite memory structure is proposed. The proposed estimator is developed under a maximum likelihood criterion using only the most recent finite observations on the window. The proposed estimator is first represented in a batch form, and then in a recursive form for computational advantage. The proposed estimator is shown...
Minimal and maximal bi-ideals in ordered ternary semigroups
May 2012
In this paper, some characterizations of minimal and maximal bi-ideals of ordered ternary semigroups were given. Moreover, the results of minimal and maximal bi-ideals of ordered ternary semigroups to ordered n-ary semigroups were generalized. Key words: Bi-ideals, minimal bi-ideals, maximal bi-ideals, ordered ternary semigroups, ordered n-ary semigroups.
Procedure for treatment of hazardous waste by MID-MIX procedure in Serbia
May 2012
This paper presents adequate treatment characteristics of the problem of hazardous waste while providing a specific example of the problem. Hazardous waste being discussed here is galvanic sludge. Furthermore, not only is the hazardous waste problem within a company discussed, but also on a national level. The MID-MIX® procedure was chosen and described as an optimal solution for adequate hazardous waste...
Production and purification of horseradish peroxidase in Pakistan
May 2012
Horseradish peroxidase is heme containing enzyme belonging to oxidoreductases and is involved in degradation of certain recalcitrant organic compounds like phenol and substituted phenol via free radical polymerization. Peroxidase was extracted and purified from horseradish by (NH4)2SO4 precipitation, dialysis and gel filtration chromatography. Spectrophotometer was used for the assay of horseradish...
A new technique for characterization of epileptic spikes using wavelet transform and neural network
May 2012
A technique proposed for the automatic detection of spikes in electroencephalograms (EEG). The important features of the raw EEG data were extracted using two methods: Wavelet transform and energy estimation. This data was normalized and given as input to the neural network, which was trained using back propagation algorithm. Energy estimation was used as an amplitude threshold parameter. The wavelet...
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