Experimental determination of layers films thicknesses
August 2013
The determination of particle induced x-ray emission (PIXE) cross sections and the concentration of elements in a material require the knowledge of the target sample thickness. In this aim, measurements of the thickness by three different methods have been performed. These are absorption of X-rays by a 55Fe source, transmission of alpha particles by a 241Am source and Rutherford backscattering of alpha...
trans-[PtCl2(NH2C6H4CO2H)2]: a platinum complex forming a two-dimensional hydrogen-bonded network
August 2013
The compound trans-[PtCl2(NH2C6H4CO2H)2] has been prepared from the hydrolysis of a platinum diimine complex, and has been characterised by X-ray crystallography. The crystal structure revealed that the compound forms a two-dimensional hydrogen-bonded network in the solid state, with pairs of O–H···O hydrogen bonds between carboxylic acid groups linking the molecules into zigzag tapes,...
Studies on drying rates of brined and spiced Clarias gariepinus (Catfish) using solar dryer
August 2013
The objective of this study was to determine the effect of brining and spicing with ginger or garlic on the drying rate of cat fish in a passive solar dryer. Samples of cat fish were solar dried under three different conditions: brine only, spiced with garlic and spiced with ginger. Their respective weight losses were used to determine the reduction in moisture contents. Graphs of drying rate versus time were plotted in...
Performance of community based organizations in managing sustainable urban water supply and sanitation projects
August 2013
The advocacy of climatic change and ever increasing poverty has its impact on environmental degradation. Most of underdeveloped countries have experienced this impact through technical, economic, institutional and social constraints on water supply and sanitation infrastructures. The impact has much effect in urban areas (informal settlements) due to the nature of such settlements. Lack of a sustainable approach and an...
Theoretical study on structural and electronic properties of 4-[(E)-[4-(trifloromethyl)-1,3-benzothiazol-2-yl]azo]naphthalen-1-ol and 1-[(E)-[4-(trifloromethyl)-1,3-benzothiazol-2-yl]azo]naphthalen-2-ol using density functional theory (DFT)
August 2013
In this work, the structural and electronic properties of 4-[(E)-[4-(trifloromethyl)-1,3-benzothiazol-2-yl]azo]naphthalen-1-ol (ortho-OH) and 1-[(E)-[4-(trifloromethyl)-1,3-benzothiazol-2-yl]azo]naphthalen-2-ol (para-OH) using density functional theory (DFT) were presented. The calculated vibrational frequencies were compared very well with experimental. The total energy for the isomers A and B were -4277242.55 and...
Evaluation of extraction methods for the analysis of selected polybrominated diphenyl ethers and hexabromobiphenyl (BB-153) – application to aqueous environmental samples
August 2013
The increasing evidence of the presence of organic pollutants in different aqueous matrices has led to the development of many analytical techniques. The isolation of these compounds from the aqueous matrices remains an integral component of these techniques. In this study, the performance of three different extraction methods, namely separatory funnel, magnetic stirring and solid-phase extraction methods commonly...
Improved energy efficiency of photogalvanic cell with four dyes as photosensitizers in Tween 60- Ascorbic acid system
August 2013
The objective of this work was to increase the energy efficiency of photogalvanic cell using four dyes; Amido Black 10B, Bromocresol purple, Carmine and Biebrich scarlet as photosensitizers in Tween 60-Ascorbic acid system. Observed values of photopotential, photocurrent, fill factor, conversion efficiency and storage capacity for Tween 60 - Amido Black 10B - Ascorbic acid system were 996 mV, 420 µA, 0.38,...
Role of finite element method (FEM) in predicting transverse modulus of fiber-reinforced polymer (FRP) composites: A revelation
August 2013
The present investigation aims to validate finite element method (FEM) in micromechanical analysis of a unidirectional continuous fiber reinforced composites and experimental verification of results in case of fiber-matrix debond. Available analytical models are reviewed, compared and are seldom in agreement with each other in case of transverse modulus of unidirectional continuous fiber reinforced composites. Reasons...
Assessment of leachate effects to the drinking water supply units in the down slope regions of municipal solid waste (MSW) dumping sites in Lahore Pakistan
July 2013
The aim of this study was to evaluate seasonal as well as moderate temporal effects on deep groundwater quality by the dumpsites leachate in the Lahore Metropolitan with a population of about 8 million. Groundwater samples for this study ware drawn from groundwater supply units installed by local government for the provision of drinking water to the residents. The groundwater in down slope regions from municipal solid...
Novel method of iron removal from underground dug well waters in communities around Okada town, Ovia North-East L.G.A. Edo State
July 2013
Some indices of pollution were studied in water samples from 25 dug wells randomly selected from Okada town and it’s environ. Physicochemical parameters measured include temperature, pH, colour, turbidity, total dissolved solids (TDS), toxic shock syndrome (TSS), total hardness, Ca, Mg, Fe, Mn, nitrate and phosphate etc. The results of the study showed that dug wells from this area contain Fe and Mn concentrations...
Modelling of solar radiation for West Africa: The Nigerian option
July 2013
The United Nations Framework Convention on Climate Change (UNFCCC) reports indicate that those who are least responsible for climate change are also the most vulnerable to its projected impacts. In no place is this more evident than in Sub Saharan Africa, where greenhouse gas (GHG) emissions are negligible from a global scale. In Africa, energy demands could be the major factor that may lead to the increase of its...
Study of the effect of particles size and volume fraction concentration on the thermal conductivity and thermal diffusivity of Al2O3 nanofluids
July 2013
In this study we present new data for the thermal conductivity enhancement in four nanofluids containing 11, 25, 50, and 63 nm diameter Aluminum oxide (Al2O3) nanoparticles in distilled water. The nanofluids were prepared using single step method (that is, by dispersing nanoparticle directly in base fluid) which was gathered in ultrasonic device for approximately 7 h. The transient hot-wire laser beam displacement...
Anti-islanding protection based on voltage and frequency analysis in wind turbines units
July 2013
This paper introduces a new islanding detection algorithm method based on voltage and frequency analysis for wind turbines as distributed resource units at the distribution voltage level. The proposed method is based on processing of the rate of change of q-axis component of voltage and accelerates of change of frequency. This method detects the islanding conditions with the analysis of these signals. The studies...
A method for placement of distributed generation (DG) units using particle swarm optimization
July 2013
Nowadays, the penetration of distributed generation (DG) in power networks takes special place worldwide and is increasing in developed countries. In order to improve voltage profile, stability, reduction of power losses etc, it is necessary that, this increasing of installation of DGs in distribution system should be done systematically. This paper introduces an optimal placement method in order to sizing and sitting...
Adaptive neuro-fuzzy inference system (ANFIS) islanding detection based on wind turbine simulator
July 2013
This paper presents a passive islanding detection method based on means of a neuro-fuzzy approach for wind turbines. Several methods based on passive and active detection scheme have been proposed. While passive schemes have a large Non detection zone (NDZ), concern has been raised on active method due to its degrading power quality effect. Reliably detecting this condition is regarded by many as an ongoing challenge as...
Application of regression and multiple correlation analysis to morning hours solar radiation in Lapai
July 2013
Solar radiation in Lapai within the morning hours has been estimated by correlating meteorological parameters. This was achieved by applying the first and second order regression and multiple correlation analysis method. The correlation coefficient based on the first and second order equations in temperature and relative humidity were 0.828, 0.692, 0.860 and 0.622 while the correlation coefficient based on the multiple...
Synthesis, characterization and neuropharmacological activity of novel angular pentacyclic phenothiazine
July 2013
13H-5,14-dihydroquinoxalino[2,3-a]phenothiazine (a new pentacyclic ring system) was synthesized by condensation of diphenylamine and sulphur, which on nitration yielded 1-nitrophenothiazine. Reduction of this compound afforded 1-aminophenothiazine dihydrochloride and subsequent protection of this product with acetic anhydride gave 1-acetylaminophenothiazine. The nitration of this acetylated compound yielded two isomeric...
Quantum chemical calculations on molecular structures and solvents effect on 4-nitropicolinic and 4-methoxypicolinic acid
July 2013
The density functional theory (DFT) (B3LYP) was used to study the solvents effect on electronic properties of 4-methoxypicolinic acid (4MOPIC) and 4-nitropicolinic acid (4NPIC). The calculated vibration frequencies at DFT/6-311++G** were compared to that of un-substituted picolinic acid to know the effect of donor/acceptor substituent on the molecules. Five solvents namely acetone, ethanol, diethyl ether, N,...
Neuro-fuzzy decision learning on supply chain configuration
July 2013
This paper describes the computational automatic supply chain configuration (SCC) based on fuzzy logic prediction actualizing automatically the chain stages considering different customer service level petitions. Each level is selected in accordance with the inference and the knowledge base process supplies (KBPS). The SCC model as an intelligent processes selector (IPS), allows dynamical configuration in accordance...
Geoelectrical evaluation of groundwater potentials of Bwari basement area, Central Nigeria
July 2013
An investigation has been made of the groundwater potentials of Bwari basement area using solely geoelectric surveys. Twenty vertical electrical soundings along different transverses were conducted with maximum electrode spacing of 300 m. The results revealed that the area is characterized with 3 to 6 geoelectric subsurface layers with variability in resistivities and thicknesses of the different layers. The overburden...
Experimental study of air-water turbulent flow structures on stepped spillways
July 2013
Stepped chute flows are characterized by intense turbulence and strong flow aeration, but most studies did not investigate the turbulence characteristics. In this study, highly turbulent air-water flows skimming down a large-size stepped chute were systematically investigated. An experimental study of detailed air-water flow properties measurements were introduced in different types of flow regimes on a stepped chute...
The ability to use light emtting diode (LED) as emergency, instead of gas lamp or tingistin lamp in home lighting
July 2013
An electric circuit was made and connected to an alternative current that was passing through lower transformer. This process would produce a current the value of which was 500 mA and a voltage of 6 volt was used to charge battery. When the voltage source (alternative current) was cut, the circuit started lighting. We measured the charge and discharge in addition to time lapses to compare them with the results of the...
Assessment of arsenic levels in Guguletu and Langa rivers in Cape Town, South Africa
July 2013
This study investigates the baseline environmental levels of arsenic (As) in two rivers; one of which traverses through Guguletu (R1) and the other running by the peripheral of Langa (R2) residential areas in Cape Town. The rivers were monitored for As in upstream, midstream and downstream stations for twelve months, during consecutive summer and winter seasons between 2011 and 2012. The collected water samples were...
Design and evaluation of combined solar and biomass dryer for small and medium enterprises for developing countries
July 2013
A small scale demonstration model consisting of a combined solar and biomass cabinet dryer with 3 equally spaced drying trays was designed, constructed and evaluated. The results, obtained using fresh yam chips as test material over a four day test period, were satisfactory and useful for optimization purposes. Maximum tray temperature of 53°C was obtained in combination with solar and biomass heating sources even...
Dissolved and particulate trace elements’ configuration: Case study from a shallow lake
June 2013
Trace element distribution was monitored for Uluabat lake water polluted with point and non-point sources in Bursa. An examination of Zn, Cr, Ni, Cu, Pb, As, B concentrations during the study period indicated that the particulate phase at the bottom of the water column were high in regard to dissolved phase. The source of trace elements in thedeeper parts of the water column was derived from the higher...
Potential reduction of concrete deterioration through controlled DEF in hydrated concrete
June 2013
Delayed ettringite formation (DEF) is a chemical reaction with proven damaging effects on hydrated concrete. Ettringite crystals can cause cracks and their widening due to pressure on cracked walls caused by the positive volume difference in the reaction. Concrete may show improvements in strength at early ages but further growth of cracks causes widening and spreading through the concrete structure. In this study,...
Linearization of Zoeppritz equations and practical utilization
June 2013
The theory and practical utilization of simplification of the original general expressions for the reflection of compression and shear waves at a boundary as a function of the densities and velocities of layers in contact are presented in this paper. The original general expressions are highly non-linear and presumed to defy physical insight. Elimination of the properties of Vs and ΔVs in favour of ï³...
Characterizations of semi-groups that are semi-lattices of left groups
June 2013
Zadeh in 1965 introduce the concept of a fuzzy set which now have a wide range of applications in various fields of Engineering Sciences, Computer Science and Management Sciences. It is worth mentioning here that for applications of fuzzy sets mostly associative algebraic structures are used such as in 2003, Mordeson, Malik and Kuroki have discovered the applications of fuzzy semigroups in fuzzy coding, fuzzy...
Synthesis of perovskite CaTiO3 nanopowders with different morphologies by mechanical alloying without heat treatment
June 2013
Mechanical alloying (MA) method is one of the methods used for large scale production of different nanopowders. In this study, calcium titanate (CaTiO3: CTO) nanoparticles have been synthesized via mechanical alloying (MA) without using heat treatment. The milled powders and CTO were characterized by XRD, SEM, and zetasizer. It is found that the CTO has a diameter of 30 - 70 nm with different...
Hurricanes and cyclones kinematics and thermodynamics based on Clausius-Clapeyron relation derived in 1832
June 2013
Juxtaposing Clausius-Clapeyron relation derived in 1832 with Hydrodynamic concept of atmosphere parcel of air leads to the discovery of an essential property of the troposphere that will deeply ameliorates information contained in literature and audiovisual productions on tropical weather. It is indeed a rectification of the use of an ideal gas principle which enshrined the idea that, hot air is lighter than cold air...
A comparative study of biogas production using plantain/almond leaves and pig dung, and its applications
June 2013
Plantain/almond leaves and pig dung were used as substrates in anaerobic biodigester for producing biogas by batch operation method within the mesophilic temperature range of 20.0 to 31.0°C. The study was carried out to compare biogas production potential from plantain/almond leaves and pig dung wastes. The cumulative biogas produced from the plantain/almond leaves was 220.5 L while the cumulative biogas from the...
Electrical characterization of conducting poly(2-ethanolaniline) under electric field
June 2013
We have studied conductivity and molecular weight obtained poly(2-ethanolaniline), P2EANi. P2EANi synthesized according to the best ratio of obtained molar of initiator to monomer at different reaction times. Then we measured the mass and conductivity of the obtained polymers in the best time of polymerization. Next, we repeated these reactions under different electric fields in the most appropriate time and measured...
A Mode-I crack problem for two-dimensional problem of a fiber-reinforced thermoelastic with normal mode analysis
June 2013
The aim of the present work is to investigate the influence of the Mode-I crack on the plane waves in a linearly ï¬ber-reinforced. A general model of the equations of coupled theory (CD) and Lord-Shulman (L-S) theory with one relaxation time are applied to study the influence of reinforcement on the total deformation for an infinite space weakened by a finite linear opening Mode-I crack is solving. The material is...
Novel nano photocatalyst for the degradation of sky blue 5b textile dye
June 2013
A new Nano photocatalyst, CuO-Al2O3-ZrO2-TiO2 was synthesized by co-precipitation for the removal of textile dye under ultra violet and direct sunlight. The synthesized catalyst was characterized by using X-rays diffraction, X-rays fluorescent, thermo gravimetric analysis, DRS, scanning electron microscopy and EDX. The dopants reduced the recombination of ecb- and hvb+ and decreased the band gap of...
Decentralized management of a multi-source electrical system: A multi-agent approach
June 2013
The objective of this paper was design and implementation of a self-adaptive management system of a set of production sources in a changing and unpredictable energy demand environment. The strategy proposed made it possible to achieve optimal management of the energy resource production of the electrical system facing the changing demand. After showing the need to follow «intelligently» the behavior of...
The improved Riccati equation mapping method for constructing many families of exact solutions for a nonlinear partial differential equation of nanobiosciences
June 2013
In this paper we apply the improved Riccati equation mapping method to construct many families of general exact solutions of a nonlinear partial differential equation involving parameters of special significant for nanobiosciences and biophysics, namely, the equation of nano-ionic currents along microtublues. Comparison between our new results and the well-known results are given. The nonlinear equation elaborated here...
Polyaniline/Fe3O4 coated on MnFe2O4 nanocomposite: Preparation, characterization, and applications in microwave absorption
June 2013
Conductive polyaniline (PANi)/Fe3O4 is coated on the MnFe2O4 nanocomposite with multi core shell structure was synthesized by in-situ polymerization in the presence of dodecyl benzene sulfonic acid (DBSA) as the surfactant and dopant and ammonium persulfate (APS) as the oxidant. The structure and magnetic properties of Fe3O4 coated on the MnFe2O4 nanoparticles were studied by using powder...
Photovoltaic solar cell simulation of shockley diode parameters in matlab
June 2013
In this work, the Shockley diode parameters were simulated using the Matlab software package with the solar cell I - V and P - V characteristics in focus. Our model has been based on previous studies while the effects of varying cell temperature, series resistance, Rs ambient irradiation and diode quality factor were put into consideration and the output current and power characteristics of the PV model simulated,...
Detection and wavelet analysis of acoustic emission signal from partial discharge captured by multimode optical fiber and piezoelectric sensors in insulation oil
June 2013
High-voltage transformer is the most critical and expensive component in a power system network in order to ensure the stability of the system. Partial discharge (PD) detection is a technique widely used for high voltage equipment insulation condition monitoring and assessment. In this paper, the characteristics of two acoustic sensors multimode fiber optical (FO) and piezoelectric (PZT) sensor have been successfully...
Mass, energy and momentum of photon in medium
June 2013
When photon travels in a medium where the velocity is lower than the speed of light, the photon possesses both the kinetic (Ek) and the potential (Ep) energy. We proved that the energy of photon (E = nEk), where (n) is the refractive index, and the effective mass of photon in medium (m' = nm), where (m) is the effective mass of photon in vacuum. Also we proved that the momentum of photon (p = E/c) inside...
Relationship between magnetospheric interplanetary parameters and radio refractivity for quiet and disturbed days at Minna
June 2013
The relationship of magnetospheric interplanetary parameters with radio refractivity is investigated from hourly measurement of solar wind energy and interplanetary parameters for quiet and disturbed days during dry and rainy season in Minna (Latitude 9° 36' 50" N and Longitude 6° 33' 24" E) North central, Nigeria for the year 2008. The solar wind energy, magnetospheric interplanetary...
Synthesis, structural and dielectric properties of zinc sulfide nanoparticles
June 2013
Zinc sulfide (ZnS) nanoparticles were synthesized by the wet chemical method. The crystal structure and grain size of the particles were determined, using X-ray diffraction (XRD). The optical properties were studied by the Ultraviolet-Visible (UV-Vis) absorption spectrum. The dielectric properties of ZnS nanoparticles were examined using a HIOKI 3532-50 LCR HITESTER over the frequency range of 50...
Impact of dust on the photovoltaic (PV) modules characteristics after an exposition year in Sahelian environment: The case of Senegal
June 2013
The objective of this paper is to find the effect of dust on the performance of photovoltaic modules. To this end, the International Center for Research and Training in solar energy at Dakar University and the Lasquo-ISTIA Laboratory of Angers University have put in place a research project in order to investigate the impact of Sahelian climatic conditions on the photovoltaic (PV) modules characteristics....
Effect of fiber size on elastic constants of hybrid elliptical fiber reinforced lamina
June 2013
Micromechanical analysis of an fiber reinforced polymer (FRP) lamina consisting of unequal sizes of unidirectional continuous elliptical fibers of two different materials arranged in hexagonal pattern is the present subject. The objective is to observe the change in Young’s modulii and Poisson’s ratios due to change in volume fractions and ellipse aspect ratio ‘a’ of individual fibers in a...
Investigation of carbon monoxide concentration from anthropogenic sources in Lagos, Nigeria
June 2013
The work investigated the carbon monoxide (CO) concentration from anthropogenic sources in eight, different Local Council Development Authority (LCDA) in Lagos State Nigeria. The CO concentration obtained as a result of movement of cars, trucks, motorcycles, working of generators, commercial and residential activities etc., was measured using the digital carbon monoxide detector (model: DC01001) manufactured by General...
Harmonic curvature of the curve-surface pair under Möbius transformation
June 2013
The Möbius transformation is known as a part of analysis and mostly studied by the researchers and scientist who made their investigations on analysis. But in this paper it is worked together with differential geometry. It is well known that harmonic curvature of the curve is found by Hacısalihoglu and also harmonic curvatures and of the curve-surface pair that we call the...
Using social network systems as a tool for political change
June 2013
Social network sites like Facebook, Twitter and YouTube play a significant role in the political arena nowadays. They are growing engagement tools that assist in improving the political process by helping electoral candidates in communicating their political programs and thoughts to the community, as well as in rallying their campaign supporters. On the other hand, voters can also use social media sites to...
Structural properties of binary semiconductors
June 2013
Using the plasma oscillations theory of solids, 2 empirical relations have been proposed for the calculation of the structural properties such as bond-stretching central force constant (α) and bond-bending non-central force constant (β) for II-VI and III-V group binary semiconductors. We find that α =D (Ñ›ωp) 2 and β = S (Ñ›ωp) 2, where D and S are constants. The...
Triangular fuzzy based classification of IP request to detect spoofing request in data network
May 2013
In data nework data packets are normally forwarded from one router to another through networks until it gets to reach its destination node. According to the internet architecture routers in the internet do not perform any security verification of the source IP address contained in the IP packets. The lack of such a verification opens the door for variety of network security vulnerabilities like Denial-of-Service (DoS)...
The Hodgkin-Huxley neuron model on the fast phase plane
May 2013
In this paper, we showed a simplified version of the Hodgkin-Huxley neuron model, the so called fast plane-phase case. We first describe the circuit model of axon membrane with four parallel branches described by Hodgkin and Huxley and then we apply the Kirchhoff´s laws to obtain a system ordinary differential equations. We obtain numerical solutions to it with the aid of Mathematica. We also study this...
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