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...
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...
The structural properties of composites ZnS1-xCux thin films prepared by laser ablation
Article in Press
The prepared samples of thin-film composite by laser ablation method were achieved. Powders of zinc slfide with copper of weight ratios x=0, 0.2, 0.4, 0.6, 0.8wt% were mixed and then compressed by approximately 10 t. The samples were ablated by using Neodymium-YAG laser with 1000 mJ and 700 pulses obtained the plasma plume at 10-5 m bar pressure and 250°C. Results were indicated using X-ray diffraction (XRD), atomic...
Mathematical models used in the prediction of deaths due to fire accident in Taraba State, Nigeria
Article in Press
This research is concerned with the application and comparison of mathematical models for predicting deaths due to fire accident in Taraba State. This research was carried out because it was observed that whenever fire accident occurs, it claims lives and properties. Data were collected for the period of ten (10) years from 2005 to 2014 from Fire Service Board, Jalingo, Taraba State, Nigeria. Various models, such as...
Characterization prime and weakly prime left ideals in near left almost rings (nLA-rings)
Article in Press
The purpose of this paper was to introduce the notion of weakly prime left ideals in near left almost rings by studying, prime and weakly prime left ideals in near left almost rings (nLA-rings). Those are extended from prime and weakly prime ideals, respectively. Some characterizations of prime and weakly prime left ideals are obtained. Moreover, the relationships between prime and weakly prime left ideals in nLA-rings...
Article in Press
In this research, the effects of the Ni-doped, single vacancy (SV), double vacancy (DV), stone wells (STV) defects and electric-field (EF) on the adsorption of NH3 molecules on the surface of graphene are investigated by using the first-principles calculation. For this purpose, at first step we consider different configurations models, and then all selected models are optimized for this study. From optimized structures the...
Regression methods in the presence of heteroscedasticity and outliers
Article in Press
It has been observed over the years that real life data are usually non-conforming to the classical linear regression assumptions. One of the stringent assumptions that is unlikely to hold in many applied settings is that of homoscedasticity. When homogenous variance in a normal regression model is not appropriate, invalid standard inference procedure may result from the improper estimation of standard error when the...
Ex-vivo transdermal delivery of Annona squamosa entrapped in niosomes by electroporation
Article in Press
Reactive molecules derived from molecular oxygen and free radicals are commonly known as Reactive Oxygen Species (ROS). These molecules have been suggested to produce oxidative stress in cells leading to many pathological problems like diabetes, cancer, inflammation, neurodegenerative disorders, and aging. Antioxidants can remove free radicals from the human body. Therefore, it is of remarkable interest to increase the...
Article in Press
This paper presents the design of a narrowband pass unequal power divider using double splintered rectangular ring shape coupled lines. The substrate material used between the power divider and the ground is of Rogers RT 5880 (lossy) with a relative permittivity of 2.2. The shape used in design makes the power divider more efficient. The device works at 5.9 GHz with the insertion loss of -3.4 dB at one port and -5.02 dB at...
Liquid-liquid extraction of Zr(IV) from sulphuric acid medium using tri-n-octyl amine in kerosene
Article in Press
The extraction behaviour of Zr(IV) with tri-n-octyl amine (TOA) in kerosene has been studied through a novel method solvent extraction. The mechanism of extraction and the species extracted have been identified. Quantitative extraction of Zr(IV) with TOA was achieved in kerosene by changing different parameters such as acid variation, diluent effect, metal concentration variation, extractant variation, effect of chloride...
Electro-generated low-band-gap conjugated polymer based on Benzothidiazole
Article in Press
Poly (4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2,1,3-benzothiadiazole) (PBEDT) a novel low – band – gap polymer has been synthesised by electro-polymerisation of a trimer composed of precursors ethylenedioxythiophene combined with 2,1,3-benzothiadiazole. The Ultraviolet–visible (UV-V) is spectrum of the trimer in chloroform solution gave two absorption bands with peaks at 323 nm and another at 482 nm with an...
Article in Press
In this work, the authors study the influence of the Reynolds number on the heat and mass transfers in an interface air- water of a parabolic pond of retention full of water in forced convection. The free surface of the pond is crossed by a forced warm air. In the water, the vorticity-stream function is adopted. To resolve the equations in the air which are constituted by a mixture dry air and of steam, the hypotheses of...
Article in Press
In this work, we handle the space – time fractional of classical Drinfeld's Sokolov – Wilson system, the fractional (2+1) – dimensional Davey–Stewartson system and the fractional generalized Hirota- Satsuma coupled KdV systemto solve analytically. Firstly, we use fractional traveling wave transformations to convert fractional nonlinear partial differential equations to nonlinear ordinary differential...
Article in Press
We apply the two-variable )--expansion method to construct new exact traveling wave solutions with parameters of the nonlinear potential Boussinesq and ZKBBM equations. This method can be thought of as the generalization of the well-known )---expansion method given recently by Wang and co-workers (2008). When the parameters are replaced by special values, the well-known solitary wave solutions of this equation are...
Page 2 of 2, showing 31 records out of 81 total, starting on record 51, ending on 81
