Article in Press
Concrete is a major component of construction work composed of fine and coarse aggregates bind together with a cement-water solution paste produced with hydration process. Concrete is best characterized by its compressive strength and relatively low in cost as well as the availability of ingredients that makes it the most favorable component of construction compared to other materials like steel. However, this...
Article in Press
A comprehensive study of the reduced graphene oxide (r-GO) Schottky diode is presented, to extort information about the Schottky interface. An efficient analysis was performed to investigate the interface traps and electrical properties by current–voltage (I–V), capacitance–voltage (C–V), capacitance–frequency (C–f), and conductance–frequency (Gp/?–?) measurements. The high value of the ideality factor (3.16) suggested the...
Investigation of Multipath Propagation and Fade Statistics in the Coastal Area of Nigeria
Article in Press
Multipath propagation is one of the factors that cause radio signal degradation, and due to the irregularity in the atmosphere; this causes the variation in the point radio refractive gradient (PRRG) with height and time of the day as well as the season. In this paper, multipath propagation and fading in the coastal area of Nigeria is investigated, using five (5) years (Jan 2014-Dec 2018) re-analyzed data, obtained from...
Article in Press
The matrix optics formalism is applied to show that a simple Gaussian equation is enough to relate object and image distances in an optical system consisting of an arbitrary number of thick lenses in cascade immersed in air. First, it was studied the case of a single thick lens. Applying sequentially the optical matrixes corresponding to refraction and displacement of the optical ray, and imposing certain conditions on the...
Article in Press
We examine the effect of MHD flow of the Casson nanofluid model on heat and mass transfer over a stretching sheet with Thompson and Trioan slip boundary condition. The relaxation properties of the fluid flow are studied by using the Cattaneo-Christov heat flux model. The governing partial differential equations are transformed into self-similar form and solved numerically by using the spectral collocation method. The...
Physical-Chemical Characterization of Kanyu Almond Oil (Sclerocarya Birrea) For Use as Biofuel
Article in Press
Plant oil extracted from Kanyu almonds offers the potential to be an alternative to fossil fuel resources. This study aims to characterization the physic-chemical properties of kanyu almond oil, as safe indicators of the use of this biofuel for energy generators. Samples of the oils as examined were density, kinematic viscosity, acid value, and oxidation stability. The experimental results showed that the oils had...
Article in Press
Probability distributions had been used to characterize electric field intensity. In this study, Birnbaum-Saunders (B-S) and Generalized Birnbaum-Saunders (GB-S) distributions were used to model the behavior of electric field intensity within the coverage area of broadcasting radio transmitter. Usually, the availability and usefulness of the signal at the primary and secondary coverage areas are guaranteed unlike at the...
Electrical properties and phase transition of Alizarin Carmine
Article in Press
The electrical conductivity of the organic dye Alizarin Carmine has been analysed by observing the variation in the dielectric constant with the temperature. The Alizarin Carmine pellet used for the analyses has colloidal graphite electrodes. The measurement has been done using the Motwane measuring unit model BM- 100 B at the frequency of 1 KHz. Change in the temperature was observed at -95°C that decreases the...
Article in Press
Noise emissions close to venues where academic activities take place are one of the main causes of noise pollution to which people working at UNAN - Managua are exposed. Noise pollution also has a negative impact on the development of academic activities that take place within the Carlos Fonseca University Campus (RUCFA) and the Rubén DarÃo University Campus (RURD).The methodology for obtaining, processing data and...
Wavelet Transform Theory: Mathematical Principles in Gamma Spectroscopy Processing
Article in Press
Wavelet transforms (WT) has been used for analyzing different types of spectra successfully. It has certain advantages compared with the Fourier transforms (FT) for signals decompositions. In the present work, we introduce the mathematical principles of applying WT in processing gamma spectra.
Micromechanical modeling of the elastic behavior of particles-reinforced composites
Article in Press
This paper is devoted to the introduction of a micromechanical modeling of the elastic behavior of composite materials with spherical reinforcements. The model is based on the generalized self-consistent scheme (GSCS) and homogenization/localization techniques over the entire representative volume element (VER). The composite is modeled by the three phase model and the methodology is based on the integral equation and...
Article in Press
Gully erosion is an environmental problem that has over decades threatened Anambra State as well as other parts of Nigeria and countries of sub-Saharan Africa. Gullies threaten the soil, water, material resources and agricultural productivity and cause human losses annually. It accounts for the severe environmental degradation in Anambra State and the South-East of Nigeria arising from heavy runoff and soil loss....
Article in Press
Mineralogical and geochemical tests were conducted on bentonitic samples obtained from Imo shale and the Ameki-Bende formations in Anambra basin of southeastern Nigeria, in order to evaluate the potential for use in drilling mud formulation. Fifty samples were collected and screened based on composition, grain size, degree of alteration, and filtration conditions. Four of the samples namely SP1, SP2, SP3 and SP4 that meet...
Article in Press
This study presents the analysis of the variation of effective lifetime of carriers with temperature in different recombination mechanisms for aluminum nitride. Aluminum nitride is stable at high temperatures in inert atmospheres and melts about 2200â—¦C. In a vacuum, AlN decomposes at 10â—¦C. In the air, surface oxidation occurs above 700â—¦C. For hole trap region, the probability of emission of hole much greater than the...
Article in Press
This paper proposes a half-step third derivative hybrid block method with two cases of order four for solution of third Order Ordinary Differential Equations.Method of interpolation and collocation of power series approximate solution was used to generate the continuous hybrid linear multistep method,which was then evaluated at non-interpolating points to give a continuous block method. The discrete block method was...
Investigation of the ^16 O, ^20 Ne and ^24 Mg Nuclei as an alpha cluster plus core cluster
Article in Press
In this paper, the light nuclei are considered in the cluster model especially the nuclei with A=4n(n is the number of alpha particles). Therefore, the Schrodinger equation is solved from the NU method by using a local potential. First, we study ^16 O,^20 Ne and ^24 Mg nuclei as the two-cluster systems, i.e. (α+ core), and obtain their energy levels. These results are compared with experimental data. Somebody can see...
Article in Press
The high resolution magnetic field data of Monguno and environs (data maps 066, 067, 089 and 090) of the Nigerian Chad (Bornu) basin were structurally interpreted to investigate the hydrocarbon and solid mineral implications of the basin by determining the magnetic basement depth and delineating the basement morphology, the relief and other structural features associated with the area and their trends employing Oasis...
The Integration of Hamilton Principle with Einstein Field Equation
Article in Press
Hamilton Principle was entering into one side and Einstein Field Equation(EFE) was entering into the other side, based on the thought of relativity between reality and virtuality in physics and the Postulate of Completeness, the author would rather integrate Hamilton Principle with EFE so as to build a new physical principle------Hamilton Tensor Equation(HTE), which could substitute for Hamilton Principle and also EFE to...
Article in Press
Every aspect of oil and gas operations poses significant negative impacts on the environment in varying levels, these environmental impacts have economic and public health consequences on the indigenes of the operation locality. Produced Water discharge is one of such aspects of the upstream oil and gas operation whose potential for environmental degradation has necessitated both local and International Regulations for its...
The magnetic moment of elementary particles is studied by space vector and space curvature
Article in Press
This paper reaffirms the basic agreement of the material space theory: (1) Space is a physical existence; (2) "Force" is the action to space, and "force" is equal to the reciprocal value of "time"; in the absence of special description, "force" is the reciprocal of time; (3) There is a steady velocity field in three-dimensional space, whose intensity is the speed of light C. (4) Mass is a property of space produced by...
Article in Press
Caffeine is one of the compounds found in coffee beans and other parts of coffee plant. However, its relative content in different coffee plant parts is least researched. Therefore, this study was designed to determine the content of caffeine in green coffee leaves and beans. In this work, we report content of caffeine in green coffee beans and leaves of coffea arabic using UV/Vis spectrometer with liquid-liquid extraction...
Two values of the Constant G obtained from Inclining-Pull Projection Method
Article in Press
The Newtonian gravitational constant is regarded as the most fundamental constant. So far, more than 200 experiments have been done to measure its true value. But large discrepancies in those results appeared. Owing to the weakness of the gravitational interaction and the impossibility of shielding its effects, it is very difficult to find new method to measure G. Thus, most previous experiments were based on the torsion...
Article in Press
This paper proposes a method for evaluating the available solar energy according to different type of sky (clear sky, moderately covered sky and covered sky). Four semi-empirical models for estimating solar radiation (Link Cloudiness Factor (LCF), Perrin-Brichambaut (PB), Ghouard (GD), BirdHulstrom (BH)) have been used to predict solar radiation accoording to the sky conditions. An analysis of the influence of seasonal...
Gravitational Waves as a Test of General Relativity
Article in Press
General relativity has been very successful as a model for space and gravity. It is supported from a range of experimental results. With the advent of the detection of gravitational waves, another platform exists to trumpet its triumph. The merger of black holes has provided evidence in support of the theory of Einstein. Furthermore, the one neutron star merger so far detected provides much more information because of the...
INTEGRATED GEOPHYSICAL APPROACH FOR SEDIMENTARY OUTCROP AT NORTHWESTERN PENINSULAR MALAYSIA
Article in Press
An outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. In recent years, outcrop studies have become very important to understand the geology of the earth. The lack of studies on outcrops depends on the interpretations and observations at the surface of the earth only. Besides that, lack of specific physical value for the type of materials can cause misinterpretation of...
Gravitation - flat power field
Article in Press
A new principle of origin and the nature of the action of gravity forces are proposed. Forces of universal attraction have plane-symmetrical directions. On this basis, it becomes possible to reconsider certain regularities in natural science. The new principle of gravitation will allow to explain physical paradoxes, to improve methods of scientific research and some technological processes.
Article in Press
Salacca zalacca (Gaertn.) Voss (salak fruit or snake fruit) is a species of palm tree native to Southwest Java and North Sumatra in Indonesia. It is known as one of the tropical fruits in Malaysia. It is a reddish-brown scaly skin with pleasant pineapple, pear and banana-like aromas. Its strong pleasant aroma, S. zalacca has high potentiality in the perfumery and pharmaceutical industries. The volatile aromas of plants are...
Mineralogical and Major oxide Characterization of Panyam clays, North – Central Nigeria
Article in Press
Clay minerals are form over long periods of time, through weathering as a result of gradual chemical breakdown of rocks rich in feldspar. The extent of weathering is determined by many factors. Most common constituent mineral of clays is often one of the members of the mica mineral group. They include illite, sericite, muscovite, and biotite. Others are kaolinite, smectite, mixed-layer clays and chlorite. This paper...
Analysis of clearness index on a regional scale
Article in Press
Analysis of daily average clearness index and relative possible number of sunshine hours n/N have been made using accumulated meteorological data obtained from Nigeria Meteorological Agency (NIMET) station, Oshodi, Nigeria from 1985 to 2014. The values of regression constants ( and ), sum of the regression constants ( ), Mean-Bias-Error (MBE), root-mean-square-error (RMSE) and correlation-coefficient (RC) are presented...
Article in Press
A theoretical analysis is performed to examine the flow of an incompressible polymeric liquid (Maxwell fluid) between two infinite isothermal stretching disks. The convective heat and mass boundary conditions are taken into account. Further, the effects of viscous dissipation and chemical reaction are also carried out. The governing equations associated with momentum, energy and concentration profiles are reduced into set...
Spacelike Surfaces with a Common Asymptotic Curve in Minkowski 3-Space E_1^3
Article in Press
In this paper, we study the problem of finding a family of spacelike surfaces from a given spatial asymptotic curve in Minkowski 3-space. We obtain the parametricrepresentation for a spacelike surface pencil whose members share the same asymptoticspacelike curve as an isoparametric curve. Using the Frenet frame of the given asymptoticcurve, we present the spacelike surface as a linear combination of this frame and...
Article in Press
Mining activities brings the artisan miners to close proximity with naturally occurring radioactive materials (NORM) which exposes the miners to ionizing radiation. In this study, estimation of radiological hazards and risks related to work activities in Tantalite mining sites in Oke-Ogun, Oyo State has been carried out. A total 40 samples comprising of (12) Tantalite ore ({Fe,Mn}Ta206), 17 soil samples and 11 waste rocks...
Dual solutions for the Modified Fourier and Fick,s theories for Carreau nanofluid
Article in Press
In the current framework, an investigation is carried out on the flow of dual solutions of Car- reau nanofluids in the presence of Cattaneo-Christov double diffusion with focus on heat and mass transfer which includes the effects of Brownian motion and thermophoresis parameter. A nonlin- early shrinking sheet has been used to create the flow. The thermal and concentration diffusions are considered by introducing...
Article in Press
In this work, densities and viscosities for the binary mixtures of 1-hexyl - 3-methylimidazolium tetrafluoroborate, [C6mim][BF4], with butyl acetate, have been determined at 298.15 K. These data were used to calculate the excess molar volumes VEm for the mixtures. It is shown that values of VEm are negative, in the whole concentration range. The VEm values show their minimum at the composition of χIL≈ 0.3, exhibit a...
Article in Press
The study of spin-density-wave (SDW) and superconducting order parameter is a core topic for research on the FeAs-based high Tc superconductors. By using mathematical model Hamiltonian for the system and Green’s function formalism (creation and annihilation operators), we have obtained expressions for superconducting transition temperature (TC), spin density wave transition temperature (Tsdw), superconductivity...
A TECHNIQUE FOR DETERMINING EFFICIENCY OF AEROSOL SAMPLER
Article in Press
Viscosity, an important aspect in air flow at the lowest layer of the atmosphere was determined during Harmattan period as 1.88 x 10-5 Nsm-2 ± 0.04%. Kinematic viscosity, another important parameter on atmospheric motion was established as 0.54 x 10-5 m2s-1 ± 0.02%. For contribution to protection of human and ecological systems from dangerous levels of air pollution, a new technique for determining the efficiency of...
Article in Press
Er3+ -doped CaSO4-P2O5 glasses with successive increase in Er2O3 contents (from 0.1 to 0.9 mol %) were prepared using melt-quench method aimed to improve their chemical stability and optical behavior. The structure was investigated using FT-infrared and Raman spectroscopy. Non-crystalline phases were detected by X-ray diffraction (XRD) spectroscopy. From the Raman spectra, Qi were identified (i = 0, 1, 2 and 3) stands for...
Modeling and simulation of a high-pressure polyethylene tubular reactor
Article in Press
The complex world of polymerization has become an important topic for research due mainly to the great investments it demands and the difficulty in operation of the huge plants that exist to produce polymers. Many papers have been written about this, most of them focusing on the reactor performance and its stability. In the present work, a model and simulation for the high- pressure polyethylene tubular reactor has been...
Article in Press
The solutions of spin and pseudospin symmetries with Trigonometric scarf potential are obtained in the presence of a new tensor interaction which breaks down the energy degeneracies in both symmetries leading to atomic stability. The nonrelativistic equation is obtained by taking the nonrelativistic limit of the spin symmetry. A simplified condition for energy equation for Formula method for special case is also given....
Feasibility analysis of hybrid electricity generation system by HOMER for Mauritanian northern coast
Article in Press
The reported work was motivated by the energy needs in the Mauritania region and the utility of the search features of a software system, named HOMER (Hybrid Optimization of Multiple Energy Resources), for feasibility analysis of a hybrid power generation system (HS) for the Mauritanian northern coast. This study analyzed a sample of the available wind resources to meet the energy needs of these localities, using the HOMER...
Laplace decomposition method for Whitham-Broer-Kaup shallow water waves equations
Article in Press
In this paper, the Laplace decomposition method was applied to find travelling wave solutions of the Whitham-Broer-Kaup (WBK) system. To illustrate the capability of the approach, two numerical examples are given where the propagation and the error of the obtained solutions are shown in comparison of its exact solution. The approximate solutions are calculated in form of convergence power series with easily computable...
Article in Press
This work studied the comparative analysis of meteorological parameter (temperature, solar radiation and relative humidity) of satellite and Nigerian Meteorological Agency (NIMET) data at Kano, Kaduna, Owerri and Sokoto for 2006, 2007, 2008, and 2010, respectively. Statistical tools of mean bias error (MBE), root mean square error (RMSE) and correlation coefficient (r) were determined to validate the data. The results...
Article in Press
Solutions of partial differential equations are of great importance for mathematicians and scientists. In this paper, the author likewise calculated exact Langrage multiplier and it progressively connects to the definite results of Helmholtz and nonlinear parabolic equations. This study shows the advantages of exact Lagrange multipliers and their coupling with Variational Iteration Method. Computational work shows that the...
Analysis of long-term rainfall trends over Nigeria
Article in Press
Monthly mean of rainfall data (mm) between January to December for the period 1901 to 2006 for 23 stations (grid points) over Nigeria were analyzed in this study. The trends of rainfall over the 23 stations were examined statistically based on the time series, mean, standard deviation of the rainfall data. The study period were sub-divided into 30-year Climatic means and compared with World Meteorological Organization...
Effect of Eddy diffusion on atmospheric electrical processes in a fair weather environment
Article in Press
Most of the past studies have been concentrated towards the average current that flows from the thunderstorm into the global electric circuit, the role of equalization layer, and the variations of electric field for maintaining the ionosphere’s electric potential difference in the atmosphere, which are directed downward between the equipotential surfaces of the ionosphere and ground. The analytical relation for both the...
Article in Press
This study investigates the seasonal variations of rainfall and its decadal anomaly over Nigeria and the possible role of solar and geomagnetic activities. Sunspot number and geomagnetic aa index were used as solar indices. Monthly mean daily rainfall data from Nigeria Meteorological (NIMET) Agency was used in this study. Descriptive, bivariate, and power spectral density (PSD) analyses, as well as Mann-Kendall trend test...
Preparation and characterization of Holmium doped borate glass
Article in Press
Holmium doped borate glasses were prepared by conventional rapid melt-quench method. The X-ray powder diffraction (XRD) pattern indicates the amorphous nature of Holmium doped borate glass. Photoluminescence spectrum gives an idea of the optical properties of Holmium doped borate glass. Determination and differentiation of the various vibrational modes were done using Fourier transform infrared spectroscopy (FTIR)...
Article in Press
Atmospheric Physics is a fascinating scientific discipline, presents a comprehensive coverage of global meteorology and climatology. It has provided essentially a viable means for tackling environmental issues, key to vital and challenging problems facing weather and climate predictions. This Paper discusses a basic understanding of atmospheric physics as an essential field behind issues of current concern on climate...
Article in Press
Nickel–titanium shape memory alloys (NiTi) are relatively special group of metallic biomaterials. Extraordinary properties of NiTi shape memory alloys are widely employed in medical applications (orthopedics, orthodontics, urology, etc.) owing to their desirable properties, such as superelasticity, relatively low modulus and good corrosion resistance. Furthermore, toxicity and carcinogenesis of Ni ions released from NiTi...
Article in Press
In this paper, we report the measurement of impedance spectroscopy for the bis(2-amino-4-methylpyridinium) tetrachloridozincate (II) compound in the frequency range 209 Hz to 5 MHz with the temperature ranging from 308 up to 368 K. The impedance plots have shown semicircle arcs at different temperatures and an electrical equivalent circuit has been proposed to explain the impedance results. Detailed analysis of the...
Page 1 of 2, showing 50 records out of 64 total, starting on record 1, ending on 50
