International Journal of
Physical Sciences

  • Abbreviation: Int. J. Phys. Sci.
  • Language: English
  • ISSN: 1992-1950
  • DOI: 10.5897/IJPS
  • Start Year: 2006

IJPS Articles

October 2018

Deriving an expression for electron-reflection-coefficient at metal-semiconductor-interface of dye-sensitized solar cells

This work aims to derive an expression to describe the reflection coefficient of an escape electron from metal-semiconductor interface of DSSC.  The derivation was obtained by analytically solving electron diffusion equation with assumptions of steady state DSSC and negligible current flow at the outer most part of the film. The derived corrected Richardson-Dushman equation including a reflection of electron wave...

Author(s): Lurwan Garba  

October 2018

Quantification and correction of the Thomsen’s Delta Anisotropy for improved quantitative seismic interpretation in “AMFO” Field, Western Niger Delta

The Niger Delta is a sedimentary deposit with continuing sediment deposition to date. In a stratified earth, seismic waves tend to propagate faster along layers than across layer boundaries. Shales, due to the clay minerals they contain, exhibit similar behavior. As a result, velocities derived from surface seismic are often faster than well-derived velocities, causing depths of structures from surface seismic...

Author(s): Ogagarue D. O. and Ebeniro J. O.  

August 2018

Radionuclide concentration: The coal ash effect

Radionuclide concentrations in coal ash, soil mixed with coal ash and soil were determined using the gamma spectroscopic method. The average activity concentrations of 226Ra, 232Th, and 40K in coal ash samples were found as 35.0, 5.8, and 109.4 Bq/kg, respectively. The average activity concentrations of 226Ra, 232Th and 40K in soil mixed with coal ash samples varied from 21.2 to 30.8, 48.6 to 82.7, and 162.5 to 180.1...

Author(s): Amakom M. Chijioke, Orji E. Chikwendu, Iroegbu Chinedu, Eke C. Benedict, Nkwoada U. Amarachi, Madu D. Afam, Ugochuwu G. Kosisochukwu and Oforma J. Tochukwu  

July 2018

Mineralogical and geochemical properties of clay deposits in parts of Southeastern Nigeria

The rocks underlying many parts of Southeastern Nigeria had undergone extensive alterations to form considerable clay deposits. The mineralogical compositions of some of these clay deposits were evaluated with the X-Ray Diffraction (XRD) method to ascertain the suitability of the deposits as raw materials. Results of the analyses indicated that kaolinite (Al2Si2O5 (OH)4) is the dominant clay mineral. Traces of bentonite...

Author(s): Onyekuru S. O., Iwuoha P. O., Iwuagwu C. J., Nwozor K. K. and Opara K. D.  

July 2018

Theoretical models for prediction of methane production from anaerobic digestion: A critical review

This work presents a critical analysis for three models group of methanogen potential prediction. The first group allows determination of the methane productivity of substrates, through three models (BMPthCOD, BMPthAtC and BMPthOFC). The BMPthCOD is suitable for a first approximation calculation. BMPthAtC and BMPthOFC are more accurate; however, require a complex characterization of substrates. The second models group...

Author(s): Mohamed Mahmoud ALI, Nourou DIA, Boudy BILAL and Mamoudou NDONGO  

June 2018

Energy and exergy analysis of a solar photovoltaic module performance under the Sahelian Environment

This work focuses on the performance study of a photovoltaic solar module based on energy and exergy analysis. The experimental data were obtained by precise measurements during a clear sky day March 20, 2018 and a cloudy day March 27, 2018 in the Laboratory of Chemistry and Materials Physics (LCPM) at the Assane Seck University of Ziguinchor, Senegal (12° 34 N, 16° 16 E). Exergy, energy and power conversion...

Author(s): Ahmed Sidibba, Diene Ndiaye, Diouma Kobor, Menny El Bah and Sidi Bouhamady  

June 2018

Gross alpha and beta activity concentrations in soil and some selected Nigerian food crops

Gross alpha and beta activity concentrations in soil, cassava and fluted pumpkin (leaf and stem) were investigated using a gas flow proportional counter. The gross alpha activity concentrations for the fluted pumpkin were between 3.55 and 13.95 Bq/Kg and 3.53 and 3.61 Bq/Kg for the leaves and stems, respectively. The gross alpha activity concentrations for cassava and soil samples ranged from 0.07 to 0.60 Bq/Kg and 0.35...

Author(s): Chijioke M. Amakom, Chikwendu E. Orji, Benedict C. Eke, Chinedu Iroegbu and Bridget A. Ojakominor

June 2018

Effect of annealing temperature on the optical properties of Sb-ZnO thin films prepared using co-sputtering technique

Transparent conducting oxide thin films of Sb-ZnO were prepared on optically flat quartz by radio-frequency (RF) sputtering method. The scan electron microscope was used to characterize the topological morphology of the surface of the as-prepared and annealed films at (300, 400, 470, and 525°C) for 4 h in air. The optical properties of the films were deliberated using their reflectance and transmittance spectra at...

Author(s): Hend Alkhammash

May 2018

Comparative analysis of physical and chemical characteristics of selected clays deposits found in Kebbi State, Nigeria

The intent of this paper was to explore the physical and chemical characteristics of clays in Kebbi State, Nigeria, and the clays were compared with standard clay which is considered with highest quality standard in casting. Clay’s deposits from Dukku River along River Rima, Jega River which is the tail end of River Niger and Yauri were investigated for their potentials as raw materials used for casting and...

Author(s): S. A. Salihu and I. Y. Suleiman

May 2018

Optical and structural performance of polymer/fullerene thin film based on Poly (3-hexylthiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61 [(P3HT)/PCBM] after post-annealing

The polymer solar cell is a promising candidate for the next-generation solar cells because of its light weight, flexibility and easy fabrication. Poly (3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl) propyl-1-phenyl[6,6]C61(PCBM) are, to date, the most-studied active materials around the world for bulk-heterojunction structure. Recent power-conversion efficiencies are reported up to approximately 13%. This research...

Author(s): Sunday Wilson Balogun, Yekini Kolawole Sanusi, and Adebayo Olaniyi Aina

May 2018

Seven-dimensional space-time and its objects: Arbitrary spin state, electromagnetic fields, mirror symmetry and superconductivity

To form the basis spin states of a field, vector states  of the multicomponent wave function to the four coordinates of Minkowski space that determine the position of the local observer have been added by angular extra dimensions that determine the orientation of the local observer. The generators of the Poincare group in the angular representation have been obtained. The Dirac equation (generalized for any spin)...

Author(s): Roman Sventkovsky

May 2018

Correlation of geotechnical parameters with geological formations in a basement complex and its implications on civil structure foundation

Geotechnical tests were carried out on twenty subsoil samples obtained from ten locations at the depth of 1 and 2 m within Federal University of Technology, Akure, Nigeria. The area is typical of basement complex. The test include; Natural Moisture Content, Grain Size Analyses, Specific Gravity, Atterberg Limits, Compaction, California Bearing Ratio (CBR), and Unconfined Compression Tests. The ten locations where the...

Author(s): Akintorinwa O. J. and Oluwole S. T.

April 2018

Feasibility analysis of hybrid electricity generation system by HOMER for Mauritanian northern coast

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...

Author(s): M. Soukeyna, I. B. Ramdhane, D. Ndiaye, M. Elmamy, M. M. Menou, A. M. Yahya, A. K. Mahmoud and I. Youm

April 2018

Investigating influence of the phases of solar activity cycle 23 on coronal mass ejections transit time

It has been established that Coronal Mass Ejections (CMEs) follow the phase of solar activity cycle. CMEs are known to be the major cause of geomagnetic storms which have devastating effects on earth atmosphere. Predicting their arrival times has been a major issue in space weather forecast. Influence of the phases solar activity cycle 23 on CMEs transit time were investigated using fast CMEs data with initial speed...

Author(s): Ojih Victoria B. and Okeke Francisca N.  

April 2018

A compact and sensitive avalanche photodiode-based gamma detection and spectroscopy system

This research presents the design of a simple and compact yet sensitive gamma detection system which finds optimal utility in student research and demonstration purposes. The design is based on an Avalanche Photodiode (APD), a compact solid-state device. It was argued that, by the virtue of its concise size, simplicity and lower cost, an APD based gamma detection system is a better alternative in these applications as...

Author(s): Masroor H. S. Bukhari and A. Rauf  

March 2018

A comparative study of Nigerian GNSS Reference Network’s – Global Positioning System (NIGNET’s-GPS) vertical Total Electron Content (vTEC) measurements with the International Reference Ionosphere - Total Electron Content (IRI-TEC) predictions over Calabar, Nigeria

A study of the vertical Total Electron Content (vTEC) values as measured by the Nigerian GNSS Reference Network’s (NIGNET’s) GPS receiver in Calabar with geographic coordinates: 4.95°N, 8.32°E and geomagnetic coordinates: 6.46°N, 81.59°E has been carried out for some selected days in the year 2013. The results obtained are compared with the corresponding predictions of the three topside...

Author(s): Joseph Obu, Eucharia Okoro and Sivla William

March 2018

Comparative study of commercial gas with biogas produced from co-digestion of corn cob, rice chaff, goat and dog dungs

Investigations were conducted to compare gas produced from co-digestion of corncob, rice chaff, goat dung and dog dung with commercial gas. The study was carried out anaerobically at a temperature of 29.5 to 33°C (mesophilic condition) in a mini laboratory digester (bioreactor) fabricated using guage 16 metal sheets with 80-L capacity for a 90-day retention time. The shredded corn cob and rice chaff were mixed with...

Author(s): Okolie N. P., Onifade A. K., Oladunmoye M. K. and Adegunloye D. V.

March 2018

On the effect of convective heat and mass transfer on unsteady mixed convection MHD flow through vertical porous medium

In this paper, unsteady two-dimensional convective heat and mass transfer flow of a viscous, incompressible, electrically conducting optically thin fluid which is bounded by a vertical infinite plane surface was considered.  A uniform applied homogeneous magnetic field is considered in the transverse direction with first order chemical reaction. An analytical solution for two-dimensional oscillatory flow on...

Author(s): M. M. Allan, and S. M. Dardery,

March 2018

Simulation of the impact of climate change on peanut yield in Senegal

This paper treats the impacts of climate change on peanut yield in Ziguinchor (Southwest of Senegal) during the near future (2021 to 2050) and the far future (2071 to 2100). The Decision Support System for Agrotechnology Transfer (DSSAT) crop model was run using daily weather data (maximum and minimum surface temperature, rainfall and solar radiation) of four (4) regional climate models (RCMs) of the Coordinated...

Author(s): Alioune Badara Sarr and Moctar Camara

February 2018

Interpretation of aeromagnetic data over some parts of Mambilla Plateau, Taraba State

The data covering Mayo Daga and Gashaka areas of Taraba State has been interpreted by applying source parameter imaging (SPI) and forward and inverse modeling methods. From the quantitative method of interpretation, it was found out that the magnetic intensity within the study area ranges from -129.9 to 186.6 nT in which the area is noticeably marked by both low and high magnetic signatures which may be as a result of...

Author(s): YAKUBU John Akor, ILEAGU Immaculate Ukamaka and IGWE Emmanuel Awucha  

February 2018

Improvement of the homotopy perturbation method to nonlinear problems

This paper proposes an effective improvement of the homotopy perturbation method (HPM) by using Jacobi and He's polynomials to solve some nonlinear ordinary differential equations. With this method, the source terms of ordinary differential equations can be expanded in series of shifted Jacobi polynomials. Numerical results are given in this paper to illustrate the reliability of this method with nonlinear ordinary...

Author(s): J. F. Alzaidi and A. A. Alderremy  

February 2018

Investigation of gravity anomalies in parts of Niger Delta Region in Nigeria using aerogravity data

Gravity anomalies in parts of the Niger Delta region, Nigeria, were investigated through the interpretation of aerogarvity data with the objectives to determine the thickness of the sedimentary basin, establish the basement topography, density contrasts and the geological models which will give information about variation of geological structures. Four sheets of digital airborne gravity data were used for the...

Author(s): Ekpa M. M. M., Okeke F. N., Ibuot J. C., Obiora D. N. and Abangwu U. J.  

February 2018

Green synthesis of silver monometallic and copper-silver bimetallic nanoparticles using Kigelia africana fruit extract and evaluation of their antimicrobial activities

Aqueous extract of Kigelia africana fruits have been utilized in the syntheses of silver nanoparticles (AgNPs) and copper-silver bimetallic nanoparticles (Ag-CuNPs). The synthesized nanoparticles have been characterized using UV-vis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDX), x-ray diffration (XRD) and transmission electron microscopy (TEM)....

Author(s): Providence B. Ashishie, Chinyere A. Anyama, Ayi A. Ayi, Charles O. Oseghale, Elijah T. Adesuji and Ayomide H. Labulo

January 2018

High-latitude thermospheric zonal winds during low solar activity period

Changes resulting from the cyclical nature of the sun’s energy output result to variations in thermosphere-ionosphere system parameters. The prolonged low solar activity period of solar cycle 23 provides an opportunity to study the thermosphere-ionosphere system parameters when the sun was at its ground state. The CHAMP satellite has provided wind data that can be used for investigation of neutral thermospheric...

Author(s): Sivla W. T., Ugonabo O. J. and Okoro E. C.  

January 2018

Study of the performance of a system for dry cleaning dust deposited on the surface of solar photovoltaic panels

This study was carried out at the International Center for Training and Research in Solar Energy (CIFRES) and its main purpose was to study the performance of a solar module cleaning system. To handle this work, a measuring platform consisting of two polycrystalline (pc-Si) PV modules was designed. The modules were connected to a waterless cleaning system on the surface of the solar panels. The platform also contained a...

Author(s): Mohamed Cherif AIDARA, Mamadou Lamine NDIAYE, Amy MBAYE, Mamadou SYLLA, Pape Alioune NDIAYE and Amadou NDIAYE

January 2018

A comparative study of maximum power point tracker approaches based on artificial neural network and fuzzy controllers

The performances of a photovoltaic (PV) module connected to a load through a conversion stage (chopper, inverter) are linked to the average electricity output including the delivered power. Nevertheless, the efficiency depends on atmospheric parameters as temperature, irradiance, and wind speed. To make electrical power available, Maximum Power Point Trackers (MPPT) algorithms are developed to keep up the PV module at...

Author(s): Moustapha Séne, Fatou Ndiaye, Marie E. Faye, Saliou Diouf and  Amadou S. Maïga

December 2017

Spectroscopy and chemical analysis of natural dye from Sorghum bicolour

Many plants produce very attractive flowers, leaves and fruits. Colour pigments that are derived from nature are believed to be environmentally friendly because of their non-toxic, non-carcinogenic and biodegradable nature. In this project, colour pigment from ethanol extract of Sorghum bicolour was investigated using three different spectroscopic techniques (UV-Vis, FT-IR and GC/MS). The effects of dyeing parameters;...

Author(s): O. Babatunde

December 2017

Microstructure and mechanical properties correlation for the steel: A comparative methodology of educational research for physics and mechanical engineering trainings

An academic methodology based for experimental evaluation of materials treatment is presented. The study is centered in an educational research emphasis about microstructure evaluation and heat treatments in steels samples machined according to ASTM E8 specifications. The uses of metallographic techniques and hardness/tensile tests for analyzing experimental variations due to structural changes are included. Different...

Author(s): B. González-Vizcarra, F. Mesa, A. Delgado-Hernández, M. Avila-Puc, J. M. Colores-Vargas, F. J. Ramírez-Arias, M. Siqueiros-Hernández and L. Cruz-Vazquez

December 2017

Intersection of lineaments for groundwater prospect analysis using satellite remotely sensed and aeromagnetic dataset around Ibodi, Southwestern Nigeria

This research investigates groundwater potential of Ibodi and its environs using satellite imagery remotely sensed and aeromagnetic dataset. This hydrogeological investigation involved the extraction of lineaments from Landsat Thematic Mapper (TM) satellite imagery and aeromagnetic lineament of the area. The processed image revealed lineaments trending in approximately NE-SW direction; also, Landsat and aeromagnetic...

Author(s): Ilugbo S. O. and Adebiyi A. D.

November 2017

Variability of quiet-time diurnal amplitude and phase of cosmic ray count rates in the mid- and high latitudes

Studies have been done on the variability of cosmic rays flux during solar quiet days at mid and high latitudes. By using the 5 quietest days for each month, the monthly mean diurnal variation of cosmic ray anisotropy have been derived for the period 1981 to 2007, which covers part of cycles 21, 22 and 23. These quiet days are days during which the sun is relatively magnetically quiet, leading to less anisotropic...

Author(s): Okiyi Ugochukwu, Okpala Kingsley C., Tsor James O., and Egbunu Friday

November 2017

Investigation on equinoctial asymmetry observed in Niamey Station Center for Orbit Determination in Europe Total Electron Content (CODG TEC) variation during ~ solar cycle 23

This is an investigation of equinoctial asymmetry in Total electron content (TEC) variability at Niamey (Latitude: 13° 30' 49.18" N, Longitude: 2° 06' 35.28" E) using the Global Ionospheric Maps model constructed by the Center for Orbit Determination in Europe (CODG model) during solar cycle 23, that is, from year 1999 to year 2009. Niamey Center for Orbit Determination in Europe...

Author(s): Ouattara F., Zerbo J. L., Kaboré M., and Fleury R.

November 2017

Estimation of sedimentary thickness using spectral analysis of aeromagnetic data over Abakaliki and Ugep areas of the Lower Benue Trough, Nigeria

Aeromagnetic data over Abakaliki and Ugep areas of the lower Benue Trough were interpreted to determine the depth to magnetic source rocks of the area. The study area covered latitudes 5° 30' and 6° 30'N and longitudes 8° 00' and 8° 30'E with an estimated total area of about 6000 km2. Quantitative interpretation was carried out using spectral analysis method to compute for depth to...

Author(s): Alasi T. K., Ugwu G. Z. and Ugwu C. M.

November 2017

Solar wind plasma associated with Dst < -50 nT during solar cycle 24

This study analyzed the correlative study between the peak intensity of the geomagnetic storm, interplanetary magnetic field (IMF) and the peak value of various plasma parameters during the solar cycle 24. This study has been performed using hourly values of the geomagnetic storm time (Dst) < -50 nT for the period 2008 to 2016. 173 events of disturbance storm time with solar wind velocity ≥ 350 km/s were selected...

Author(s): P. R.Singh, S. Ahmad, B. Nigam, P. K. Chamadia, A. K. Saxena and C. M. Tiwari

November 2017

Evaluation of the impact of partial shading and its transmittance on the performance of crystalline silicon photovoltaic modules

This paper presents on the one hand, an evaluation of the impact of partial shading on the performance parameters of two photovoltaic modules respectively in poly and mono. The current-voltage characteristic (I-V), the short-circuit current (Icc), the open-circuit voltage (Vco) and the maximum power (Pmax) were studied. In this work, the measurements were carried out under the standard conditions (STC) in order to make...

Author(s): Issa Faye, Ababacar Ndiaye, Diouma Kobor, Moustapha Thiame, Cheickh Sene and Lat-Grand Ndiaye

October 2017

Models for calculating monthly average solar radiation from air temperature in Swaziland

Solar radiation is an important energy source for mankind. Accurate data of solar radiation levels for a particular location is vital for optimum operation of solar energy transducers such as photovoltaic cells and solar thermal collectors. In this work, it is shown a linear relationship exist between monthly average temperatures and solar radiation in Swaziland. The correlation has been utilized to develop two...

Author(s): Mgidi D. Dlamini, Alakaparampil J. Varkey and Simiso K. Mkhonta

October 2017

A study of semi-annual variation of residual geomagnetic field and its association with solar and geomagnetic activity

The semi-annual variation of the residual H and Z components of geomagnetic field was studied by analyzing magnetograms with sixty-one years data. Mean monthly residual H- and Z-component field (Hdiff and Zdiff) variations were computed using appropriate technique. Semi-annual variation exhibited Hdiff peaks in the equinoxes, which for low latitudes, was higher during March/April than in September/October. In the mid...

Author(s): Egba Ibeabuchi G., Kalu Florence D., Okwesili Agatha N. and Okpala Kingsley C.,

October 2017

Radioactivity in building materials in Saudi Arabia: An overview of experimental method and Monte Carlo N-Particle (MCNP) calculation

The aims of this work were clearly to assess the norms of radiation protection for building residents against natural radioactivity. This was done through measurement of natural radioactivity in building materials using gamma ray spectrometer. The annual effective dose (HR) linked to natural radioactivity was computed to estimate the radiation hazard in building materials. Obtained concentrations of these natural...

Author(s): H. Alshammari, Abdulrahman Alghamdi and Ahmed Algammidi

October 2017

Spectral depth analysis for determining the depth to basement of magnetic source rocks over Nkalagu and Igumale areas of the Lower Benue Trough, Nigeria

Structural interpretation of aeromagnetic data over Nkalagu-Igumale area of the Lower Benue Trough of Nigeria was carried out to determine the depth to magnetic basement and delineate the basement morphology and the structural features associated with the basin and their trends. The aeromagnetic data were subjected to series of computer based image and data enhancement techniques before spectral analysis. Results of the...

Author(s): Ikeh Joachims C., Ugwu G. Z. and Asielue K.

October 2017

Analysis of organochlorine and organophosphorus pesticide residues in blood samples of sheep and rabbits from villages of Jimeta-Yola, Adamawa State, Nigeria

Blood samples of sheep and rabbits from five different villages of Jimeta-Yola, Adamawa State, Nigeria were collected for determination of organochlorine and organophosphorus pesticide residues. Preparation of blood samples was carried out using standard procedure of QuEChERS method of extraction. The concentrations of all the pesticides in blood samples of sheep and rabbits were determined using Gas...

Author(s): C. Milam, J. E. Eneche, M. Buba and R. K. Dogara

October 2017

Assessment of natural radionuclide levels in some Nigerian made poultry feedstuff

This study investigated the radionuclide contents of naturally occurring radionuclides. Ten samples of some Nigerian made poultry feedstuff and supplements were collected and analysed using NaI(Tl) gamma(𝛾)-ray spectroscopy for an accumulated time of about 29000 s. The results revealed that activity concentration of primordial radionuclides 40K, 226Ra, and 232Th for the samples ranged from 43.6 to 196.8 Bq/kg, 5.0 to...

Author(s): V. I. Ageda, E. E. Ike and S. T. Temaugee

September 2017

Optimization of electrical production of a hybrid system (solar, diesel and storage) pilot using HOMER in Biret, Southern Coast of Mauritania

The purpose of this work is to study the optimization of an hybrid system of electricity production (solar-diesel with storage) of Biret (Mauritania) using the Hybrid Optimization Model for Electric Renewables (HOMER) software. Indeed, it shows that the context and behavior of the chosen system is optimal. HOMER is used to present simulations in the most economical way. It is important to note that the application of...

Author(s): I. B. Ramdhane, D. Ndiaye, M. M. Menou, A. K. Mahmoud, A. M. Yahya, and  A. Yahfdhou,

September 2017

Studies on equalities and inequalities of heat, work and ratio of work to temperature

This research investigates relationships between resistances with heat and work. It is completely proven that the ratio of work to temperature for the realistic process is no less than that for the reversible process. The equalities and inequalities on the heat, work and ratio of work to temperature could be applied to the gravitational field and chemical reactions. The relationships between path functions and state...

Author(s): Chengshu Jin

August 2017

Problems with p6Li plasma in a fusion reactor

Problems of using proton-Lithium-6 (p6Li) fuel are energy losses that occur in a fusion reactor. Investigating the energy balance equation in this fuel is significant. The p6Li reaction is termed aneutronic, as it produces relatively few neutrons and requires none for breeding. The energy from the charged reaction products can be directly converted to electrical power at a much higher efficiency than Deuterium-tritium...

Author(s): J. Bahmani, B. Eslami and F. Mohammad Jafari

August 2017

Application of Ojih-Okeke modified empirical coronal mass ejection arrival (ECA) model in predicting the arrival time of coronal mass ejections (CMEs)

Predicting the arrival time of Coronal Mass Ejections (CMEs) with a lower value of average error of the difference between the predicted and the observed transit time is very crucial in space weather forecast. A modified Empirical Coronal Mass Ejection Arrival (ECA) model was proposed, namely, Ojih-Okeke modified ECA model to predict the transit time of twenty eight fast CMEs from the sun to the earth. This is the first...

Author(s): Ojih Victorial B. and Okeke Francisca N.

August 2017

Simulation of precipitation variations in Iran using Kriging interpolation methods

This study estimated spatial variability of precipitation in the monthly and annual scales in Iran for the period of 1975 to 2014 in 140 stations using kriging interpolation methods. In precipitation variability analysis three procedures were used: Mann-Kendall test, Sen's slope estimator and spatial trend patterns. Results show that there are both increasing and decreasing trends in monthly precipitation in Iran....

Author(s): Majid Javari

August 2017

Influence of solar and geomagnetic activity on climate change in Nigeria

This study investigates the possible effects of solar and geomagnetic activity on climatic parameters in Nigeria. Data of sunspot number and geomagnetic aa index from 1950 – 2012 and 1950 – 2010 were used as solar indices respectively. Monthly mean daily rainfall, minimum and maximum temperature data from 1950 – 2012 for 15 stations were used as climatic parameters. Descriptive and bivariate analyses...

Author(s): Francisca Nneke Okeke and Moses Owoicho Audu

July 2017

Variability of maximum temperature and its decadal anomaly over Nigeria: Possible connection with Solar and geomagnetic activity

This work investigates the variability of maximum temperature and its decadal anomaly in Nigeria and the possible role of Solar and geomagnetic activity. Descriptive, bivariate and spectral analyses, as well as Mann-Kendall trend test, were employed in analyzing the data used in this study. Temperature anomaly was computed using the base period, 1981 – 2010. Results revealed that seasonally, temperature varies...

Author(s): Moses Owoicho Audu, Francisca Nneka Okeke and Eucharia Chidinma Okoro

July 2017

Estimation of depth to magnetic source bodies of Nsukka and Udi areas using spectral analysis approach

The study was aimed at estimating the depth to magnetic source bodies in Nsukka and Udi areas which falls within the Anambra basin. Aeromagnetic data were used and Spectral Analysis approach was employed in the quantitative interpretation. The total magnetic intensity (TMI) contour map which ranges from -53.1 to 133.7 nanoTesla (nT) was separated into regional and residual contour maps to produce a residual aeromagnetic...

Author(s): Gladys Ujunwa Edeh, Johnson Uchenna Abangwu, Agatha Ngozi Okwesili, Mirianrita Ngozi Ossai and Daniel Nnaemeka Obiora

June 2017

Omnidirectional High Reflectors using 1-D Photonic Crystals

Much interest has been paid to omnidirectional dielectric mirrors based on the 1-D dielectric multilayers because these are better than metal mirrors owing to their low optical loss, high reflectivity and high mechanical robustness. In these applications, the required position and width of the reflection band can be obtained by adjusting the layer thickness and refractive indices of the constituent materials. Here, the...

Author(s): Pandey J. P.

June 2017

A derivation of the Kerr metric by ellipsoid coordinate transformation

Einstein's general relativistic field equation is a nonlinear partial differential equation that lacks an easy way to obtain exact solutions. The most famous of which are Schwarzschild and Kerr's black hole solutions. Kerr metric has astrophysical meaning because most cosmic celestial bodies rotate. Kerr metric is even harder than Schwarzschild metric to be derived directly due to off-diagonal term of metric...

Author(s): Yu-ching Chou M. D.

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