Nigerian Journal of Theoretical and Environmental Physics
Nigerian Journal of Theoretical and Environmental Physics (NJTEP) is an international peer-reviewed journal that publishes articles on theoretical, experimental and environmental physics. NJTEP is a fully open access online journal published by the Nigerian Institute of Physics (NIP).
Petrophysical Analysis of Reservoir Quality using Key Production Parameters: A Case Study of the G-Oil Field within the Niger Delta Basin
Production parameters of reservoirs such as Porosity (<!-- [if gte msEquation 12]><m:oMath><m:r>∅</m:r><m:r>)</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> , Permeability (K) and Water Saturation (Sw) are among the fundamental properties that determine a reservoir’s quality, defining its ability to store hydrocarbon and CO2.The Petrophysical analysis (production parameters) of the G-Oil Field in the Niger Delta basin was aimed at assessing the quality of the reservoirs in supporting hydrocarbon exploitation and carbon sequestration. Interactive Petrophysics (IP) Software was used to analyse 8 well log data in LAS format. 18 geologic reservoirs were delineated using the combination of Basic Logonal, Porosity/Water saturation algorithm and the Cut-off & summation algorithm of the IP software. Production Petrophysical parameters such as Effective Porosity (<!-- [if gte msEquation 12]><m:oMath><m:r>∅</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> eff), Permeability (K) and Water Saturation (Sw) were determined using the Tixier, Wyllie-Rose and Indonesian equations respectively. Results show that <!-- [if gte msEquation 12]><m:oMath><m:r>∅</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> effis in the range of 14.2% - 27.5% adjudged to be good porosity to very good porosity while Sw values in all 18 reservoirs ranged between 13.1% and 45.7%. K ranged between 181.01mD and 7942.091mD, placing it within the ‘Very good - Excellent’ permeability classification. Mean value of <!-- [if gte msEquation 12]><m:oMath><m:r>∅</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> eff, Sw and k for the G – Oil field are 22.8%, 31.0% and 1780.941mD respectively. These values as reviewed fell in the quality classification of Very good porosity, Very good Water Saturation and Excellent Permeability. These imply that the G – Oil field has good quality reservoirs which are highly prolific in terms of hydrocarbon production and suitable for Carbon Sequestration.
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Evaluation of Effective Doses from Natural Radioactivity in Soil and Plant Samples at Federal University Dutsin-Ma, Main Campus, Katsina State, Nigeria
The presence of naturally occurring radioactive materials (NORMs) such as ⁴⁰K, ²²⁶Ra, and ²³²Th in soil and plant is a common environmental phenomenon due to their geogenic origin. Assessing their concentrations is essential for understanding radiological exposure risks, particularly within institutional and residential environments. This study investigated the levels of ⁴⁰K, ²²⁶Ra, and ²³²Th in soil and plant samples from the Federal University Dutsin-Ma (FUDMA) main campus using gamma-ray spectroscopy. In soil, activity concentrations ranged from 20.36–47.86 Bq/kg (²²⁶Ra), 21.03–64.57 Bq/kg (²³²Th), and 81.56–234.84 Bq/kg (⁴⁰K), with mean values of 33.43, 43.16, and 164.32 Bq/kg. Compared to UNSCEAR global averages, levels of ²²⁶Ra and ²³²Th were slightly elevated, while ⁴⁰K was lower. Plant samples showed lower activity: 13.73–43.91 Bq/kg (²²⁶Ra), 16.67–50.96 Bq/kg (²³²Th), and 19.63–75.61 Bq/kg (⁴⁰K), with averages of 25.06, 33.10, and 37.30 Bq/kg. Outdoor gamma dose rates ranged from 19.63–75.61 nGy/h (soil) and 17.93–47.90 nGy/h (plant), while indoor levels reached 134.09 nGy/h. Annual effective doses (AEDγ) from soil ranged from 0.64–1.43 mSv/yr (mean: 0.92), and from plant 0.20–0.50 mSv/yr (mean: 0.35), within the ICRP 1 mSv/yr public dose limit. Ingestion dose estimates (AEDing) revealed ²³²Th as the dominant contributor: 9.93×10⁻⁴ mSv/yr (soil) and 1.52×10⁻³ mSv/yr (plant). AGED values ranged from 198.37–490.59 mSv/yr in soil and 122.12–327.20 mSv/yr in plant, with soil averaging 334.64 mSv/yr above the global average of 300 mSv/yr. Locations near the Senate Building and Faculty of Life Sciences suggest potential localized risk, emphasizing the importance of regular monitoring and precautionary measures in high-occupancy zones.
Spatial and Probabilistic Assessment of Radiation and Cancer Risk in Nigerian Seaports
Background ionizing radiation (BIR) in seaport environments contributes to public radiological exposure, yet few studies have quantified this risk in Nigerian ports. This study assessed BIR, annual effective dose equivalent (AEDE), and excess lifetime cancer risk (ELCR) across Warri, Koko, and Burutu seaports. Field measurements were collected at 15, 10, and 7 locations per port, respectively. Descriptive analysis revealed mean BIR values of 0.010 ± 0.002 µSvh⁻¹ (Warri), 0.009 ± 0.001 µSvh⁻¹ (Koko), and 0.012 ± 0.002 µSvh⁻¹ (Burutu), with corresponding AEDE estimates well below the 1 mSvy⁻¹ public exposure limit. Mean ELCR values ranged from 0.206 × 10⁻³ (Koko) to 0.251 × 10⁻³ (Burutu), approaching the UNSCEAR reference level of 0.29 × 10⁻³. Burutu exhibited the highest ELCR, likely due to localized sediment retention zones and port-specific operational features, despite its small size and limited infrastructure. Monte Carlo simulations incorporating instrument uncertainty confirmed the robustness of ELCR estimates, while spatial mapping highlighted micro-zonal hotspots consistent with measured values. Comparison with Onne Port indicated substantially lower ELCRs at the studied seaports, emphasizing the importance of site-specific risk assessments. These findings demonstrate that, although current exposures are within regulatory limits, continued monitoring is recommended, particularly in areas with elevated BIR. The study is limited by its single-season field measurements and small sample size, which may constrain broader generalization. Nonetheless, the combined spatial and probabilistic approach provides a robust baseline radiological data critical for environmental management and public health policy in Nigerian coastal ports.
Investigation of the Specific Heat Capacity, Density and Viscosity of Different Combinations of Groundnut and Palm Kernel Oil
The specific heat capacity, density, and viscosity of oil samples are affected by their chemical composition, temperature, and blending ratios. Palm kernel and groundnut oil exhibit distinct physical properties due to their unique compositions. In this work, we combined both oil samples at different ratios, producing 9 combinations and 2 original samples. Groundnut oil has a higher specific heat capacity due to its Medium-Chain Triglycerides (MCTs). Both samples experience a decrease in density as temperature rises, with groundnut oil being slightly denser. Additionally, viscosity decreases exponentially with increasing temperature, and palm kernel oil is more viscous. A comprehensive understanding of these properties in oil mixtures is essential for optimizing their use in various industrial applications. The results demonstrate a relationship between oil composition and heat retention properties. Groundnut oil exhibits a higher specific heat capacity, and increasing palm kernel oil content in the blend leads to a lower heat retention capability. The results characterized the specific heat capacity of groundnut oil, palm kernel oil, and their mixtures. Groundnut oil exhibited a higher specific heat capacity, with values of 2.54 J/g°C for pure groundnut oil and 2.16 J/g°C for pure palm kernel oil. The specific heat capacities of the mixtures followed a linear trend, indicating that the thermal properties of oil mixtures can be predicted based on their composition. These findings have practical implications in food processing and bio-fuel production. The results provide appropriate selection and application of oil blends in thermal systems. This study presents a detailed analysis of these thermo-physical properties for blends of palm kernel oil and groundnut oil in eleven different samples, offering valuable data to expand the existing body of knowledge.
The Effects of Temperature and Humidity on Air Quality in Small Industrial Area
This study investigates the relationship between temperature, humidity, and air quality in small industrial areas. The research aims to determine how these environmental factors influence air pollutant concentrations, particularly CO2 levels, and whether optimal temperature and humidity ranges can be identified to improve air quality. Data was collected using the PCE-AQD 50 air quality monitor, measuring temperature, humidity, CO2 concentration, and other pollutants. The study employed a quantitative approach, analysing real-time atmospheric data from a small industrial setting. The results indicate a strong correlation between temperature, humidity, and air quality. Higher temperatures were associated with increased CO2 levels, while humidity variations affected pollutant dispersion. An optimal range of temperature and humidity was identified, where air quality remained within acceptable limits. The findings provide valuable insights for environmental monitoring and industrial air quality management. By understanding how atmospheric conditions impact pollutant levels, industries can implement strategies to improve workplace air quality and comply with regulatory standards. Further research is recommended to explore these relationships across different industrial environments.
Analysing Spatial and Temporal Variability of Solar Radiation Using Wavelet Spectrum Transforms: Case Studies from Nigeria and the United States
Solar radiation, a fundamental driver of Earth's climate system, exhibits significant spatial and temporal variability across different geographical locations. This study employs wavelet spectrum transforms to analyse hourly solar radiation data spanning two decades over selected cities: Ibadan and Lagos in Nigeria, and New Richmond in the United States. Continuous wavelet transforms with the Morlet wavelet function are utilized to dissect the complex dynamics of solar radiation patterns. The analysis reveals distinct temporal trends and spatial distributions of solar radiation, providing insights into environmental sustainability, agricultural productivity, and socio-economic implications. By elucidating the intricate relationship between solar radiation variability and geographical locations, this study contributes to inform decision-making in renewable energy planning, climate adaptation strategies, and public health interventions.
Investigation of Groundwater Potential Zones Using Integrated Geophysical Techniques at Apaken Area, Sagamu, Southwestern Nigeria
Groundwater potential zones in Apaken Sagamu, South Western Nigeria was investigated using electrical resistivity and the natural electric field combined approaches. Twelve VES stations and six 2D electrical resistivity tomography (ERT) profiles were probed utilizing Schlumberger and Wenner array modes. respectively. The VES and 2D ERT data were processed and inverted using partial curve matching/WINRESIST and RES2DINV softwares, respectively. Natural electric field (NEF) technique was also employed on the traverses using PQWT. Three to five geo-electric layers are revealed by the results of the interpretation of the VES data: the topsoil, which has resistivity values between 55.5 and 747.3 Ωm and thicknesses between 0.4 and 2.9 m; laterite soil layer, which has resistivity values between 225.6 and 8985.8 Ωm and thicknesses between 0.8 and 18.3 m; sandy clay layer, which has resistivity values between 504.3 and 5477.8 Ωm and thicknesses between 6.5 and 34.6 m; and the layer of ferruginous medium to coarse sand, which has resistivity values between 603 and 4422.8 Ωm. The overburden thickness ranges from 1.2 to 24.0 m. Ferruginous fine sand layer of the VES stations constitutes the main aquifers’ zone. Based on reflection coefficient and overburden thickness values used to infer groundwater yield status, 50% of total VES points had moderate to high groundwater yield whereas the remaining 50% exhibit very low to low groundwater potential. According to longitudinal conductance values of the overburden units, two marked aquifer protecting capability zones were pinpointed: the poor (91.67%) and weak (8.33%). The identified moderate to high groundwater yield zones (VES stations 4, 6 and 11) with their associated moderate protective capability were located on the west and northwest sides of the study area, and thus suggested for drilling. The result of 2D resistivity and NEF concur at traverses 3 and 4 indicating good yield of groundwater zones.
Diurnal Patterns of Fair-Weather Atmospheric Electric Field in Nigeria: Deviation from Global Standards
The first continuous measurements of fair-weather atmospheric electric field in Nigeria reveal distinctive diurnal patterns that fundamentally challenge conventional assumptions about atmospheric electrical behaviour in tropical regions. While the global electric circuit is traditionally characterized by the Carnegie curve derived from maritime measurements, the influence of regional aerosol loading on atmospheric electrical patterns in dust-affected tropical environments remains poorly understood. This study aims to establish the first comprehensive atmospheric electrical climatology for Nigeria and quantify the impact of local aerosol influences on diurnal electric field patterns. Based on 418 fair-weather days over 30 months at Lokoja (7°49'N, 6°44'E), the atmospheric electric field exhibits a pronounced double-peak structure with morning (08:30 LT) and evening (19:45 LT) maxima, reaching amplitudes 2.8 times the daily mean during the dry season. This pattern contrasts sharply with the classical Carnegie curve, showing a weakly negative correlation (r = -0.42) that indicates dominant local aerosol influences over global electric circuit signals. Harmonic analysis reveals that 87% of temporal variance is captured by the first three harmonics, with the 12-hour semidiurnal component contributing 24%—substantially higher than the <5% typical of maritime stations. The diurnal amplitude factor varies systematically from 3.4 during Harmattan dust periods to 1.8 during the wet season, directly tracking regional aerosol loading patterns. These findings establish the first baseline atmospheric electrical climatology for Nigeria and demonstrate the necessity of developing region-specific standards for atmospheric electricity research in dust-affected tropical environments. The results have significant implications for global electric circuit modelling and highlight West Africa's unique role in continental atmospheric electrical processes.
Extended Generalized Uncertainty Principle: Mathematical Framework for Astrophysical Applications
We present a comprehensive mathematical framework for extended Generalized Uncertainty Principle (GUP) formulations and their systematic application to astrophysical systems. Through rigorous dimensional analysis and comparative evaluation of competing theoretical models, we establish a unified approach for incorporating quantum gravity effects into macroscopic astronomical observations. Our analysis reveals fundamental scaling relationships between microscopic quantum gravity parameters and observable astrophysical phenomena, providing the theoretical foundation for observational constraints on minimal length scales. The framework developed here offers a systematic methodology for translating Planck-scale physics into testable predictions for neutron star structure, black hole thermodynamics, and gravitational wave signatures. We demonstrate that while individual quantum gravity corrections appear negligible, their cumulative effects in extreme astrophysical environments can potentially reach observational thresholds, particularly in gravitational wave observations of binary neutron star mergers, where tidal deformability measurements offer unprecedented sensitivity to the underlying equation of state modifications.
Groundwater Exploration in Nifor Area of Edo State using Electrical Resistivity Method
Groundwater exploration was carried out in Nigerian Institute for Oil Palm Research (NIFOR) community in Ovia North-East Local Government Area of Edo State, Nigeria using electrical resistivity method. It lies between latitude of 6° 32′ 12.12″ N and longitude of 5° 37′ 23.52″ E. The geology of the study area is overlain by the Benin Formation. The study area is hilly and had little natural topographical variations. The topography is generally low, lying area with gentle slope. The vegetation is made up of trees, shrubs and grasses. Their main livelihood is farming and trading. The method employed in this study involves the measurement of apparent resistivity with depth and also for measurement underlying rocks structure such as sedimentary beds or depth of water table. The equipment employed for taking Vertical Electrical Sounding (VES) readings was Parsi (A.C) Earth Resistivity meter. The soundings were taken using Schlumberger array with maximum current electrode separation of 430m.A total of four locations were surveyed along Cattle Yard Road, Iyamu Street, and Church Street and to Feeding 31 Street (locations 1, 2, 3 and 4). The data acquired were interpreted using computer software IPI2WIN. It was discovered that all VES locations have six layers with apparent resistivity ranging from 0.675Ωm to 616291Ωm with depth ranging from 0.5m to 129m.The major lithologic units penetrated by the sounding curve were lateritic sand, clay and fine wet sand. The results from the survey areas were correlated with the existing borehole driller’s log of NIFOR for proper interpretation. The results defined the existence of aquifer with low resistivity of 0.675Ωm immediately after 5th layer in the areas under investigation. The existence of a probabilistic aquifer layer propose the study area may be a potential location for groundwater exploration, and I therefore recommend that the results of this research work should be used by drillers before a borehole is sunk.
Radioactive Element Distribution in Nigerian Coal Deposits: Implications for Environmental and Health Risks
Coal mining and utilization pose significant environmental and health risks due to the presence of naturally occurring radioactive materials (NORMs). Nigeria, with its vast coal reserves is no exception. This study investigates the distribution of radioactive elements in Nigerian coal deposits using NaI(Tl) based gamma-ray spectroscopy technique. The specific activity concentrations of the radionuclides ranged from 52.56 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>±</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> 3.59 Bq/kg to 117.45 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>±</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> 5.71 Bq/kg for 40K, 16.22 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>±</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> 3.50 Bq/kg to 19.54 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>±</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> 3.87 Bq/kg for 226Ra and 16.88 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>±</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> 1.54 Bq/kg to 51.75 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>±</m:r></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> 3.99 Bq/kg for 232Th. The results indicated that thorium concentrations were much higher than the United Nation Scientific Committee on the Effect of Atomic Radiation (UNSCEAR, 2000) permissible limit of 30 Bq/kq. This potent radiological health risk to vital body organs and tissues, hence the need to limit exposure time or use proper shielding equipment by miners and people living around coal fired power plants. Similarly, the results of the annual gonadal dose equivalent were slightly less than the ICRP permissible limit of 300 <!-- [if gte msEquation 12]><m:oMath><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>μ</m:r><m:sSub><m:sSubPr><m:ctrlPr></m:ctrlPr></m:sSubPr><m:e><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>S</m:r></m:e><m:sub><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>v</m:r></m:sub></m:sSub><m:sSup><m:sSupPr><m:ctrlPr></m:ctrlPr></m:sSupPr><m:e><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>y</m:r></m:e><m:sup><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>-</m:r><m:r><m:rPr><m:scr m:val="roman"/><m:sty m:val="p"/></m:rPr>1</m:r></m:sup></m:sSup></m:oMath><![endif]--> <span lang="EN-US" style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: Arial; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"> . Hence, the need to reduce exposure time (during work hour) especially by the miners and people around coal fired power plants.
The Magnetic and Aharonov-Bomh Flux Fields of Carbon Monoxide Diatomic Molecule with Energy-Dependent Screened Kratzer Potential
An energy-dependent potential is a type of quantum mechanical potential in which the potential energy explicitly depends on the particle’s energy, rather than solely on its spatial coordinates as in conventional potentials. Energy-dependent potentials (EDPs) have gained attention in quantum mechanics due to their ability to model systems where the interaction strength varies with the particle’s energy, offering a more flexible description of molecular and nuclear interactions than conventional static potentials. This study analytically solves the two-dimensional Schrödinger equation with an Energy-Dependent Screened Kratzer Potential (EDSKP) using the Nikiforov-Uvarov (NU) method to obtain the energy eigenvalues of a carbon monoxide (CO) diatomic molecule under the influence of Magnetic and Aharonov-Bohm (AB) flux fields. The energy spectra are computed for different quantum numbers, showing that the energy levels decrease with increasing magnetic and AB-flux field strength. This decrease is more pronounced when the energy slope parameter is negative, indicating a field-induced stabilization of the molecule. Conversely, the energy levels increase rapidly when the energy slope parameter is positive, reflecting a stiffening interaction. These behaviors are graphically confirmed and offer insights into the quantum mechanical response of molecules under external perturbations. By adjusting the potential parameters, the well-known screened Kratzer potential model is recovered. In the absence of external fields and with a substitution for the magnetic quantum number, the energy eigenvalue of the three-dimensional Schrödinger equation is retrieved as a special case, which aligns with previous studies. These results provide useful perspectives for molecular physics, quantum control, and materials science
Energy-Dependent Screened Kratzer Potential
Assessment of Natural Radioactivity and Heavy Metal Accumulation in Selected Edible Fruit Nuts from Lagos and Ogun State Markets, Nigeria
Edible fruit nuts are highly valuable to humans for nutritional, economic, medicinal, and environmental reasons, hence are in high demand in our local markets. This study assesses the levels of naturally occurring radionuclides and heavy metals in six commonly consumed edible fruit nuts—peanuts, cashew nuts, walnuts, date nuts, tiger nuts, and kola nuts—sourced from major markets in Lagos and Ogun States, southwestern Nigeria. The analysis aimed to determine the potential radiological and toxicological health risks associated with their consumption. Gamma-ray spectrometry was employed to evaluate the activity concentrations of radionuclides (40K, 226Ra, and 232Th), while heavy metal content, including lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni), cobalt (Co), copper (Cu), zinc (Zn), arsenic (As), and mercury (Hg), was determined using atomic absorpti on spectrometry. Results revealed that the activity concentration of 40K in all samples exceeded the UNSCEAR (2000) threshold of 412 Bq/kg, while 226Ra and 232Th remained below permissible limits. The internal hazard index, radium equivalent, absorbed dose rate, and annual effective dose values were also below internationally recommended levels, suggesting no immediate radiological health risks. For heavy metals, Ni and Cr showed relatively higher concentrations, especially in tiger nuts and kola nuts, though still within acceptable limits. Essential elements like Zn and Cu were present in moderate amounts, indicating nutritional value alongside trace-level contamination. Despite the safety of these nuts for human consumption, the presence of environmentally toxic metals such as Ni and Cr underscores the need for continuous monitoring. The study concludes that while current contamination levels pose no significant health risk, proactive regulation and periodic food safety evaluations are essential to safeguard public health.
Geotechnical Investigation of Road Pavement Failure along the Mubi Bypass Road, Jambutu, Jimeta, Yola, Adamawa State
The persistent failure of road pavements manifesting as severe cracks, potholes, partial or complete collapse has left residents of communities along the Mubi Bypass Road in Jambutu in a highly distressed and disrupted condition. A geotechnical investigation was conducted to determine the causes of road pavement failure within the study area. Particle size distribution analysis revealed a predominance of fines (25.9–30.8%) and sand (59.5–64%), suggesting the presence of silty clay and silty sand. Atterberg limits indicated low plasticity, with liquid limits ranging from 20.0–23.2%, plasticity index between 20–23.2%, and shrinkage limits from 1.79–2.50%. The plastic limit was largely 0%, further confirming low plasticity soils. Specific gravity values ranged from 2.5–2.54 in failed sections and 2.29–2.51 in stable sections. Compaction characteristics showed slightly lower maximum dry densities in failed sections (2.09–2.2 g/cm³) compared to stable ones (2.19–2.2 g/cm³), with similar optimum moisture contents (8.0–8.6%). California Bearing Ratio (CBR) results demonstrated a significant drop in strength under soaked conditions. Soaked CBR values ranged from 53.9–91.1% in failed sections and 17.7–51.4% in stable sections, while unsoaked values ranged from 88.3–125.4% and 36.2–59.3% respectively. This confirmed a strong influence of moisture on subgrade strength and stability. The study attributes pavement failure to weak subsurface materials, specifically incompetent silty clay and silty sand, compounded by poor drainage and the flood-prone nature of the study area. It is recommended that effective drainage systems and soil stabilization measures be implemented. These findings provide essential guidance for the rehabilitation of existing pavements and the design of new roads.
Comparative Analysis and Performance of Empirical Radiation Models for Estimating Crop Water Requirement in Semi – Arid Region of Northern Environment of Nigeria
Water's pivotal role in urban planning and hydrological development is crucial for sustainable progress and fostering a green economy. With 97% of the Earth's surface covered by water, its proper utilization in domestic, industrial, and agricultural sectors is paramount. The study is aimed at determining the comparative analysis and performance of empirical radiation models for estimating crop water requirement in semi – arid region of northern environment of NigeriaIn a recent study, the comparison of empirical radiation equations with the Food and Agricultural Organization's Penman-Monteith 56 model, renowned for its efficacy in modeling reference evapotranspiration across various climatic zones, revealed insightful findings. The analysis highlighted the efficacy of empirical models in estimating reference evapotranspiration in semi-arid and arid regions. Notably, in the comparison between the FAO 56 PM model and newer models, such as the Stephen-Stewart (S-S) and the new ETo model, significant differences in performance were observed. For instance, in Kukawa, the R² coefficient was 31.98% for the FAO 56 PM model compared to 99.96% for the S-S and new ETo models. Similarly, the comparison yielded R² values of 31.98% and 98.46%, respectively, against the new model. In Jada, the comparison showcased varying levels of success with different models. The FAO 56 PM model achieved a success rate of 51.3%, while the S-S model scored 99.99% in comparison. Additionally Caprio models demonstrated R² values of 81.41% and 99.74%, respectively, against the new model. These findings underscore the importance of selecting appropriate models for estimating reference evapotranspiration, especially in arid and semi-arid regions, to enhance the accuracy of hydrological assessments and urban planning initiatives.
Determination of Thermodynamic Properties via Partition Function Approaches Derived from the Non-Relativistic Schrödinger Equation
A critical challenge in molecular thermodynamics is accurately predicting how variations in dimensionless potential parameters influence macroscopic properties such as magnetisation, specific heat capacity, and molecular vibrational entropy. Traditional approaches often fail to fully capture these dependencies, limiting their predictive accuracy. In this study, we address this gap by developing a rigorous framework based on partition function formulations derived directly from the non-relativistic Schrödinger equation. Our main aim is to investigate the impact of dimensionless potential parameters ( and ) and the temperature parameter (β) on energy spectrum and key thermodynamic and magnetic properties. We systematically compute the energy spectrum for a wide range of potential parameter values and analyse their effects on magnetisation, magnetic susceptibility, internal energy, free energy, entropy, and specific heat capacity. The findings reveal that energy spectrum exhibit strong dependence on these parameters, with ​ generally reducing energy levels while ​ enhances them. Magnetisation typically decreases with ​ but increases with ​ and higher temperatures, while magnetic susceptibility shows complex patterns of enhancement and suppression. Vibrational thermodynamic properties, including internal energy and free energy, also display significant variations tied to the interplay of potential parameters. This study provides a robust, first-principles-based method for understanding and predicting how microscopic potential parameters govern macroscopic thermodynamic behaviour, advancing the fundamental knowledge and practical capabilities of molecular thermodynamics
Nickel Oxide Thin Film: Room Temperature Sensing Properties for Ammonia Gas
The detection of ammonia gas is crucial in various industries due to its toxic and corrosive nature. Nickel Oxide (NiO) has emerged as a promising material for gas sensing applications owing to its unique properties. Thin films of NiO have been explored for their potential in detecting gases at various temperature. In this study, nickel oxide (NiO) thin films were deposited securely and efficiently using a convenient and affordable spin coating technique followed by annealing at 2500c. Characterization of the structural and optical properties of NiO thin films were performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX) and ultraviolent (UV) – visible spectroscopy. The XRD patterns revealed that all the prepared samples exhibited a cubic structure which matched well with the joint committee on powder diffraction standards (CPDS) database. The scanning electron microscopy (SEM) images revealed a homogeneous surface morphology for the films. The prepared samples exhibited high transparency, as evident from the transmittance spectra, and the absorption spectra were used to calculate the optical energy band gap. The prepared samples were then tested for gas sensing applications using a static gas sensing setup to detect various fuel gases such as ammonia at different concentrations (ppm) at room temperature. The result showed that the NiO thin films exhibited good selectivity and high sensitivity towards ammonia. The time response characteristics of the fabricated sensor, including response and recovery times, we calculated and recorded.
Characterization of Precamrian Basement Formations using Geophysical Methods in Ago-Iwoye Southwestern Nigeria
The characterization of basement rock is essential for obtaining the detailed information for the geological and mineral potential exploration resolves. The study presents the integrated use of electrical resistivity and magnetic methods for characterizing basement rock within Ago Iwoye, Southwestern Nigeria. The study aimed to determine the subsurface geology and alteration of the basement rocks in the area of study and to understand its mineralogical and engineering purposes. The Electrical Resistivity survey was conducted using the integrated of Dipole - Dipole and Vertical Electrical Sounding techniques in order to obtain 1 and 2 Dimensional results. The Magnetic survey used a proton precession magnetometer with a sensitivity of 0.1nT to measure the Magnetic Field Intensity. The acquired data were modeled using inversion techniques to obtain 1-D and 2-DElectrical Resistivity Tomography (ERT) that is capable of unraveling the subsurface information. The results of the electrical resistivity survey revealed a subsurface layer with resistivity values ranging from 600 to 1500 Ohm-m, which correlates with the weathered and fractured layer of the basement rocks. Below this layer, the resistivity increased to a range of 2000 to 8000 Ohm-m, indicating the presence of fresh basement rock. The magnetic survey results showed that the basement rocks have weak and variable magnetic susceptibility values, which suggest weak to moderate magnetite content. The Total Magnetic Intensity (TMI) map revealed that the underlying basement within the study area ranges from 32576- 33404.9nT. The integration of both electrical resistivity and magnetic methods provided a comprehensive understanding of the subsurface geology, structure, and alteration of the basement rocks within the study area. The results revealed that the basement rocks consist of highly resistive fresh rock overlain by a weathered/faulted layer that shows moderate conductivity. The weak magnetic susceptibility values suggest a low magnetic mineral content in the basement rocks.
Geophysical Exploration of Gold Mineralization Zones using Induced Polarization and Electrical Resistivity Imaging Methods at Itagunmodi Area of Ilesha, Osun State, Southwest Nigeria
Gold is a valuable and economically solid mineral due to its unique physical and chemical properties. However, this research investigated the potential zones of gold mineralization at Itagunmodi in Atakunmosa West Local Government Area of Ilesha, Osun State, Nigeria, through the generation of subsurface 2D resistivity and induced polarization models that provide helpful information in determining the depths and lateral distances of suspected gold deposits. The time domain-induced polarization and electrical resistivity imaging (ERI) measurements were carried out along six traverses using dipole-dipole configurations with electrode separations of 5.0 m and profile lengths ranging from 128.0-315.0 m. The apparent resistivity and chargeability data were used to generate 2D subsurface models using RES2DINV software to accurately and effectively interpret the location of gold mineralization potential zones. The results from the 2D ERI and chargeability models along traverses 1 and 2 revealed low resistivity zones ranging from 16.3-669.0 Ωm corresponding to high chargeability zones ranging from 288 to 444 msec on the 2D chargeability section, which were identified at lateral distances of 82.5-102.5, 167.0-187.5, 164.0-260, 95.0-110.0, and 55.0-75.0 m from approximated depths 9.94-26.20, 6.76-36.98, 11.0-23.0, and 6.0-12.0 m beneath the subsurface. These anomalous zones along these traverses weresuspected to harbour minerals such as goldsince they can also be attributed to quartz veins and fractures that may likely be filled with conductive materials like gold and associated base metals. This research has revealed the efficacy of electrical resistivity and induced polarization methods in delineating the suspected regions of gold mineralization.
Naturally Occurring Radionuclides Assessment in Soils of Cassava Mills within the Sedimentary Terrains of Southwestern Nigeria
The assessment of naturally occurring radionuclides in soils, which serve as their primary reservoir, provides essential insights into the soil conditions, offering a detailed understanding of the radionuclides sources, distribution patterns, and potential impacts on both the environment and human health. The activity concentrations of naturally occurring radionuclides Uranium-238 (238U), Thorium-232 (232Th), and Potassium-40 (40K) in representative soil samples obtained from five cassava processing mills (Double Crown, Ekueme, Olorungbogo, Olalandu, and Akewe) in Ilaro metropolis, Southwestern Nigeria, were assessed. Twenty (20) soil samples were collected, air dried, sieved, kept for twenty-eight days, and analyzed using a Sodium Iodide Scintillation NaI(TI) detector. The results revealed the highest mean activity concentrations of 40K in Ekueme, Olorungbogo, Olalandu, and Akewe samples, while Double Crown revealed the highest mean activity concentrations of 238U. Akewe samples showed the highest activity concentrations for all the natural radionuclides, although the values were within permissible limits. The Double Crown, Ekuneme, Olorungbogo, and Olalandu samples had values within the same range and at permissible background radiation levels. Also, the established radium equivalents, absorbed dose rates, annual effective dose equivalents, and external and internal indices for the complete set of soil samples were all below the recommended values. The parameters indicated a low radiation burden on the environment, ensuring the safety of the study area's inhabitants.
The Impact of Pressure on the Structural, Electronic, and Mechanical Properties of TiPdSn: An Ab Initio Study
The TiPdSn half-Heusler alloy structural, electronic, mechanical, and optical properties were investigated from first-principles calculations in addition to their various pressures. The projected augmented wave (PAW) type of pseudopotential within the generalized gradient approximation (GGA) was employed during the calculations. The acquired results disclosed that TiPdSn is a semiconductor with an indirect band gap. Additionally, the effect from the mechanical property revealed that TiPdSn is ductile and mechanically stable. Optical properties unveil that TiPdSn have static dielectric function of 19.42 and 24.59 at 0GPa and 150GPa respectively and the refractive index are 5.11 and 4.30 at the pressures of 0GPa and 150GPa.
A DFT Approach on the Impact of Hydrostatic Pressure on the Structural, Mechanical, Lattice dynamics, and Optical Characteristics of the Cubic Perovskite RbTaO3
The structural, mechanical, electrical, lattice dynamic, and optical features of the cubic perovskite RbTaO3 beneath pressure (0150GPa) are scrutinized using ab-initio calculations established on the spin-polarized density functional theory (SP-DFT). In accordance with the lattice parameter-energy variation curve, the compound is none ferromagnetic nor non-magnetic. Mechanical stability criteria for cubic structures disclose that the material is both brittle and stable. In agreement with the Zener anisotropy factor data, the compound displays anisotropic performance between 0 and 40 GPa and isotropic performance above 40 GPa. It was also prominent to have a semiconductor character, as seen by the electrical band structures, and the band gap changed from an indirect one at 0 GPa to a direct one at 150 GPa as a consequence of pressure application. In view of this energy gap transition, RbTaO3 is a likely material for use in photovoltaic, optoelectronic, and photochemical devices. The appearance of negative frequencies in the material makes it dynamically unstable, as can be seen from the phonon dispersion curves. The fundamental optical functions were considered, including the extinction coefficient (), optical conductivity, (), reflectivity (), electron energy-loss spectrum (), absorption coefficient spectrum (), and refractive index (). The optical characteristic indicates that the visible-ultraviolet spectrum is where cubic RbTaO3 is active
Analytical Study of Viscous Fluid Movement in a Rectangular Pipe using Diffusion Magnetic Resonance Equation
Silicene, a two-dimensional material analogous to graphene, has garnered Diffusion Magnetic Resonance Imaging (DMRI) equation is used in this research work to examine the flow of fluid in a rectangular. Having previously considered flow in cylindrical and spherical coordinates, this study explores the rectangular channel of a three dimensional - (3D) flow using DMRI equation evolved and solved analytically using the method of separation of variables (MSV) with appropriate boundary conditions applied. Relaxation times of three viscous fluids were used - crude oil, oil wax and black oil in the simulation and the values of magnetization registered by each fluid recorded. The results obtained showed that oil wax has the highest value of magnetization followed by crude oil and then black oil. The study underscores the multivarious ways diffusion MRI can be applied and its use in the analysis of flow of viscous fluid through different geometrical channels.
Dependence of Luminescence Lifetimes on Radiation Absorbed Dose from Quartz using a Time-Resolved Based Pulsing System
Time-resolved optical stimulation of luminescence is an important technique that is well established for the study of dosimetric materials including quartz, carbon doped aluminium oxide, feldspar, etc. These materials, particularly quartz, Is a material of interest in dosimetry. Time resolved optical stimulation separate in time the stimulation and emission of luminescence. The luminescence is obtained from the quartz sample using a brief light pulse and the emission of the luminescence is monitored. The aim is to investigate the influence of radiation dose on luminescence lifetimes in quartz using a more cost effective and easy to design light emitting diode pulsing system. Here, a new pulsing system based on light emitting diode is designed and is used to study the dependence of luminescence lifetimes on radiation dose in quartz. The Luminescence lifetimes measured between 5 and 200 Gy beta dose were constant at about 42.0 ± 1.3 µs. The luminescence lifetime is independent of dose because most of the luminescence is emitted from LH centres which would not have been sufficiently emptied by annealing at 500 0C prior to irradiation.
An Evaluation of Excess Lifetime Cancer Risk from Indoor and Outdoor Radiation Exposure in Okutukutu Computer Village, Yenagoa, Bayelsa State, Nigeria: A Monte Carlo Simulation Approach
Some of the components of smart phones and computers, like ceramic capacitors may contain small amounts of radioisotopes. In this work, indoor and outdoor radiation exposure rates in Okutukutu “computer village” have been measured using the in-situ method. Ten indoor and ten outdoor readings were taken during working hours using a digital radiation meter. Standard equations and the Monte Carlo approach were used to analyze the data. The results show that mean exposure rates of 0.019 mRh-1 and 0.016 mRh-1 for indoor and outdoor respectively are not significantly high above the 0.013 mRh-1 world average. Approximately 700 and 90 people out of a population of one million (106) are expected to develop cancer as a result of indoor and outdoor exposure, respectively, according to the Monte Carlo simulation's assessment of minimum probable risk (P 5% = best case scenario). However, according to the maximum likely risk assessment results (P 95% = worst-case scenario), the estimated rates of cancer development from indoor and outdoor exposures are 480 and 2090, respectively, in a population of one million (106). Similar to this, the most likely risk calculation (50%) indicates that, out of a population of one million, 1320 and 270 people, respectively, are likely to acquire cancer as a result of indoor and outdoor exposure rates. Therefore, strict and efficient procedures must be implemented to protect both traders and buyers in the environments.
Application of Dipole-Dipole Electrical Resistivity for Subsurface Probing Within Golf Club Centre of University of Benin Teaching Hospital, Benin City
Imaging Electrical Resistivity in two Dimensions to determine and ascertain the degree of erosion threat at the profound University of Benin Learning/Teaching Hospital (UBTH) Golf Club in Ovia North-East Local (district) Government Area, Benin City, Edo State, Nigeria, survey profiles ranging in length from 150 to 170 meters were conducted for subsurface and sub-structural investigations. An electrode spacing (separation) of 10 m was employed. Utilizing the Abem SAS 1000 Terrameter (Resistivity Meter), a dipole-dipole array was utilized to acquire and collect field data. To established the 2-D real resistivity of the subsurface and substructure selected for display, the field data were subjected and processed deploying Dipro software. According to the findings, topsoil, lateritic sand, particle sand, and sandstone beneath the subsurface were visualized. Within the con depth range of 0 to 5 m, the 2D results unveil topsoil with described resistivity obtainable values ranging from 349 to 4555 Ωm. The second obtainable layer is assured of lateritic, sandy sand with mathematical resistivity values between 650 and 3365 Ωm down to 10.0 m. The resistivity values of the third stratum/layer, with displayed range from 568 to 8662 Ωm at a depth of 20 meters, indicate lateritic sand, sand, and sandstone. Lateritic sand, sandstone, and sandstone are found down to 35 meters in the fourth stratum. Sand and sandstone are represented by resistivity values in the fifth horizon, which range from 956 to 22573 Ωm. 50.0 m was the furthest depth that could be imaged. The 2-D resistivity picturing (imagery) indicates the presence of an aquiferous domain (zone) and the non existence of clay division (formation), given that the range of 1-150 ohm-meters distinctively associated and linked up with clay in the study area explained the best and most appropriate area for the construction of buildings. The inverted 2-D resistivity shape (structure) depicts intermediate resistivity observed distribution near-surface >340 Ωm, which are indications (evidences) of vulnerabilities to wearing and erosion in the study area.
Resistivity, Lithology, Dipole-Dipole Method and Substructure.
Optimization of Cutoff Energy and K-Point Grid Parameters for DFT Study of Pristine and Mg-Doped Silicene
Silicene, a two-dimensional material analogous to graphene, has garnered significant interest due to its promising applications in nanoelectronics, spintronics, and optoelectronics. Doping silicene with foreign atoms, such as magnesium (Mg), can modify its properties, enhancing stability and electronic versatility. This study investigates the optimization of computational parameters for pristine and Mg-doped silicene using Density Functional Theory (DFT) simulations within the Quantum ESPRESSO framework. The convergence behavior of the plane-wave cutoff energy (Ecutwfc) and k-point grids was analyzed at doping concentrations of 3.125%, 6.25%, 12.5%, and 25% Mg. Results reveal that the optimal Ecutwfc values increase with higher doping concentrations, ranging from 60 Ry for pristine silicene to 200 Ry for 3.125% Mg doping. K-point grid analysis indicates that lower doping concentrations require relatively coarse grids, while higher concentrations demand finer grids for accurate results. This study provides a reference framework for parameter selection in doped silicene systems, offering valuable insights for future theoretical research and practical applications in the field of 2D materials.
Theoretical Investigation of Quantum Confinements in Spherical PbSrSe Semiconductor Quantum Dots
One of the IV-VI material systems that have shown promising growth and sustainability in optoelectronic applications is PbSrSe quantum dot structure (QDs) material. However, the material system belongs to the lead salt semiconductor group and has a constant energy surface with prolate ellipsoids of revolution, as well as a strongly nonparabolic energy band. In this study, the particle in a box model based on the effective mass approximation is used to theoretically investigate quantum confinement in PbSrSe spherical semiconductor quantum dots. For the first four excited states explored, it is found that the transition energies of quantum dot depends on the quantum dot size.
Theoretical Study of Exciton Properties of Dilute GaInAsN Semiconductors
In this research, the electronic band structure, electronic properties and the exciton binding energy of dilute quaternary GaInAsN alloy semiconductors are investigated. This study was aimed to theoretically study the exciton properties of dilute GaInAsN semiconductors. The effects of Nitrogen incorporation in InGaAs alloy was studied within the band anti-crossing model (BAC). The pseudopotential inputs within the virtual crystal approximation (VCA) was employed to make modifications for the nitrogen and indium related alloy disorder effects. The Harrison’s model used to study the bandstructure. In general, the results of our computations are in agreement with recent experimental findings. It is found that the presence of nitrogen in the GaInAsN alloy reduces the fundamental bandgap energy within the band anticrossing (BAC) model in the vicinity of the first Brillouin zone boundary, to . The heavy hole and electron effective masses, reduced mass, energy band gap, high frequency dielectric constant, static dielectric constant, the refractive indices, polarity, covalency, Bohr radius and binding energy are also modified by the nitrogen and indium fractions of the alloy. For all the alloy compositions studied, it was observed that the binding energies of the excitons vary between the values for InAs and GaAs . Also, the corresponding excitons Bohr radii vary between the values for InAs and GaAs . The information derived from the present study predicts that GaInAsN tunable binding energies and electronic properties are of great technological importance for mid-infrared (MIR) optoelectronics.
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In-Depth Study of Climate Change and its Impact on Terrestrial Wireless Communications over North Western Nigeria
In recent times, studies on climate change and the impact on wireless communications are gaining the attention of radio scientists and engineers for effective planning of radio link and equipment maintenance. Climate change variabilities and their implications on wireless communications over the cities of Kaduna, Katsina and Sokoto (north western Nigeria), were investigated using forty-two years’ (1980-2021) atmospheric data. Results reveal substantial degree of climate change with increase in temperature profiles for all the locations. Minimum climatic mean temperature of 27.01, 29.30 and 30.70 oC were determined in Kaduna, Katsina and Sokoto respectively. Similarly, highest mean values of 30.20, 31.80 and 32.10 oC were obtained respectively in that order. The months with the least and highest temperatures in Kaduna are December and April with 23.91 and 33.06 oC respectively. For Katsina; 25.23 and 35.76 oC were obtained, while 26.28 and 36.05 oC were obtained in Sokoto in January and April respectively; and the hottest month in the studied region is April. For precipitation, minimum mean values of 2.02, 1.19 and 1.30 mm and maximum of 5.24, 2.53 and 2.39 mm were obtained in Kaduna, Katsina and Sokoto respectively. The month with the highest amount of rainfall in all the cities is August with mean values of 8.97, 6.45 and 6.52 mm in Kaduna, Katsina and Sokoto cities. The implications of these findings on terrestrial communications are that; installed out-door communication hardware such as the transmitting tower and antenna, transmitter modules and wave guides could be subjected to perturbations that will affect their optimal performances and durability during the months of excessive temperature and rainfall. Radio scientists and engineers should incorporate climate change impacts on equipment design and employ major preventive maintenance on outdoor hardware in the months of April and August over the studied areas to ensure reliability and safe cost.