Modeling the impact of different wavelengths of sunlight on the performance of a silicon PV cell
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Previous studies have experimentally investigated the impact of filtered sunlight or monochromatic LEDs on PV cell performance. However, theoretical analyses of wavelength-specific effects remain limited. This work addresses this gap using a 1-D model to investigate the impact of different wavelengths of sunlight on the performance of a silicon PV cell using 1-D modeling, addressing the limitations of experimental...
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This research evaluates groundwater quality in Effurun, southern Nigeria, particularly focusing on contamination from solid waste sources such as dumpsites and abattoirs in Osubi, Ugbomro, and Agbarho. Employing a combination of fifteen Wenner-Werner arrays and vertical electrical sounding (VES) data, we conducted geophysical assessments to identify contamination levels. Using the WINRESIST and RES 2D inversion software,...
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The Human Immunodeficiency Virus and Acquired Immune Deficiency Syndrome (HIV/AIDS) are becoming increasingly drug-resistant in some patients, leading to treatment failure and the spread of drug-resistant strains. This undermines the effectiveness of limited treatment options such as antiretroviral therapy (ART). Therefore, it is important to assess the future progress and predict the efficacy of ART treatment. To achieve...
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This study assessed trend of Land Surface Temperature over different land use/land cover in Greater Karu Urban Area of Nigeria using multi-criteria research design. The remotely sensed imageries from Landsat TM, Landsat ETM and Landsat OLI that LANDSAT TM were obtained for 4 different epochs (1992, 2002, 2012 and 2022). The study used ESRI ArcGIS 10.8, ArcGIS Pro version 3.1.3 and Qgis version 3.22.5 for data acquisition,...
Synthesis and characterization of Ni-doped ZnO and its application of DSSC
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In this report, the metal oxide semiconductor of undoped and Ni-doped ZnO nanoparticles were prepared by solvothermal method for fabricate ZnO-based dye-sensitized solar cells as photo sensitizers of Terminalia catappa fruit using ethanol as solvent. These prepared nanoparticles were analysed by structural, optical and electrical characterizations of XRD, FE-SEM, FTIR, UV-Visible and EIS. The solar cell J-V ...
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This paper presents the results of geophysical subsurface investigations conducted along Boys’ Hostel 2 in Veritas University campus, Abuja, Nigeria. Current study aimed to determine the soil and rock properties which influences building collapse and groundwater level. The subsurface of investigated area was delineated using Electrical Resistivity Tomography (ERT) method via Schlumberger and Wenner arrays. Furthermore, 2D...
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In this study we investigate different temperature electronic energy band structure responses of silicon, germanium and gallium arsenide, at various applied hydrostatic pressures within a range that does not exceed their structural phase transition pressure. The pressure coefficients, for each material have been determined. We present an atomistic insight into the question of how much of the electronic band structure...
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The research work investigated the Hydro-geological and mineral potentials of an area of 1.0 by 1.2 kilometers. A reconnaissance survey of the area was carried out using anomalous field of the aero-magnetic intensity data covering the area. The second vertical derivative reveals structures trending in the NE – SW direction, major magnetic distortions where observed within the North-eastern and Southwestern corner of the...
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The angular distribution of the degree of polarization of diffusely transmitted solar radiation in the layers of the atmosphere due to multiple scattering on air molecules has been theoretically investigated. The calculations were carried out within the framework of the -function theory, the solutions of which were determined by the factorization method. As a result of the study, it was found that when the incident...
Synthesis and characterization of silica nanoparticles from vigna Subterranea nut shells
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Silica nanoparticles have rapidly found applications in medicine, supercapacitors, batteries, optical fibers and concrete materials, because silica nanoparticles have tunable physical, chemical, optical and mechanical properties. In most applications, high-purity silica comes from synthetic organic precursors, yet this approach could be costly, polluting and non-biocompatible. Alternatively, natural silica sources from...
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This work concerns the comparative study of the diurnal variation of the critical frequency of the F2 layer (foF2) between experimental data from the Dakar station and those of the IRI 2016 model through its URSI. The comparison was made during the solar cycles 21 and 22, during different phases and on different days of geomagnetic shock activity. The results show that at solar minimum, the graphs of the experimental data...
Global Stability Analysis of a prey - predator dynamics with prey harvesting in tropical zone
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Fluctuation of eco – system’s populations is increasingly becoming more popular due to the activities of predation and harvesting. The need to design a model to cope with its challenges has become very necessary for the species survival. We investigate a predator – prey model with prey harvesting in tropical zone. Fatokun et al (2020) analyzed and discussed the local stability of a predator – prey dynamics with prey...
Study of dispersion relation and nature of magneto hydrodynamic anisotropic instabilities in plasma
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In this paper the characteristics of dispersion relation and nature of magneto hydrodynamic anisotropic instabilities are investigated in collisionless, homogeneous, and magnetized plasma. The basic equations are derived and linearized for small perturbation under the assumption that the plasma is drifting for MHD by using the moments of the Boltzmann -Vlasov transport equations. After that the dispersion relation is...
Numerical, modeling of a solar cooker of box type to solar concentrator
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A numerical computer code simulating the operation of a solar cooker of box type to solar concentrator was established. The computer code was used to study the effect of the thermal performance of the cooker. The aim of this work is to present a mathematical model of this solar cooker model in comparison with other models, and to analyze the various parameters that influence the cooker's thermal performance. The equations...
Global solar radiation analysisusing response surface methodology in Bauchi, Nigeria
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In this work meteorological data was used to estimate the global solar radiation in Bauchi, Bauchi state, Nigeria. The study examines the impact of cloud cover, relative humidity and the daily values of global solar radiation in Bauchi, Nigeria, using different proposed empirical models for a period of 10 years (1985-1994). The Angstrom model was used as the base, while other regression equations were developed by...
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The NS-3 simulator is used in this study to compare three (3) of the seven (7) supported Fractional Frequency Reuse (FFR) algorithms, namely Soft Fractional Frequency Reuse (SFFR), Distributed Fractional Frequency Reuse (DFFR), and Soft Frequency Reuse (SFR), to assess the system performance and the effect of Inter-Cell Interference (ICI) on the Long Term Evolution (LTE) network, as FFR is an effective...
Variations of Total Electron Content (TEC) over high latitude regions during the geomagnetic storm
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The variations of Total electron content (TEC) over high latitude regions during the geomagnetic storm on August 26, 2018 were investigated. This study is based on Global Positioning System (GPS-TEC) data obtained by the UNAVCO dual-frequency GPS devices at the northern stations of Hofn and Kiruna, and the southern stations of Mawson and Syog. The results of this study show that the enhancement and variations of total...
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Access to clean water for drinking and other domestic activities remains an issue, particularly for developing countries like Nigeria. Due to the global increase in population, water demand has increased quantitatively and qualitatively over time. This paper comprehensively reviews the quality of water sources utilised for consumption in northern Nigeria during the last decade. It was found that well, and borehole water is...
Development of path loss prediction model for microwave propagations in a tropical region
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The channel losses of a Very High Frequency (VHF) base station operating on 91.9 MHz in a Suburban City of Akure, South West Nigeria, were explored in this study. A BC1173 DBC field strength meter was used to measure the received signal strength at every 1km interval along four different paths from the base station. A Global Positioning System (GPS) receiver was utilized to log the coordinates and altitude of the data...
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One of the most important problem in today's world of physics is the integrity of the four main forces of nature. This article is intended to introduce a formula that will serve as the static core formula of all forces. This theory has wave-like look to all forces and states the force in the simplest word is the energy multiplied by the motion function; or in other words, the energy which is stuck in the motion function....
Statistical analysis of crime rate and prison population in Nigeria
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Human beings and the society are vulnerable to criminality and so criminality can be likened to an oil that is able to stain a white garment when it comes in touch with the white garment. That is why it's far impossible for any society to claim to be absolutely loose from crime. The styles of crook behavior depend on the social and monetary development of a given society. As an end result, it is now not unexpected that a...
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The aim of this paper is to examine the direction of causality among some exchange rate of Nigeria Naira to US Dollar, Pounds Sterling and Euro. It made use of a time series data from the year 2005 to 2014. Toda and Yamamoto (1995) procedure was used in analyzing the data. Augmented Dickey-Fuller, KPSS unit root test, the VAR selection method, Error correction model and Granger causality test based on Toda-Yamamoto...
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The spatial diversity techniques are broken down and explained systematically along with its combination which includes Maximum Ratio Combining (MRC), Equal Gain Combining (EGC) and Simple Selection Combining (SC) under the influence of atmospheric-induce turbulence fading in Free Space Optical (FSO) communication. Diversity is a technique used to prevent or reduce multipath. Multipath is a phenomenon describing...
Theoretical and Experimental Studies of Effective Carriers Lifetime: Magnetic Effects
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In this manuscript, we present a study on the effects of magnetic field on charge carrier effective lifetime within the base of a polycrystaline PV solar cell p-n junction. This study is elaborated in two forms as a theoretical study and an experimental study. Indeed, under various magnetic field values, PV solar cell is illuminated by using the light from stroboscopic. From a theoretical approach mainly use the open...
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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
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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...
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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...
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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
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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...
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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
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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...
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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
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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
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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...
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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....
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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...
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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...
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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
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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...
The Integration of Hamilton Principle with Einstein Field Equation
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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...
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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
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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...
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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
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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...
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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
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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
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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
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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.
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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
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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...
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