Physics Access

Assessment of Heavy Metals, Gross Alpha, Gross Beta and Radon Activity Concentration in Groundwater around Doguwa and its Environs, within Kano State, Nigeria

2024-10-28T06:19:35+00:00

This study assessed the activity concentrations of gross alpha, gross beta, Radon and heavy metals in groundwater sources from illegal mining areas in Doguwa Local Government, Kano State, Nigeria. Water samples from five distinct mining areas were analyzed for gross alpha and beta radioactivity using a portable single-channel gas-free proportional detector (MPC2000B-DP) via ISO9696 and ISO9697 methods, Radon levels with a Rad7 (DURRIDGE) detector, and heavy metals with atomic absorption spectroscopy. Gross alpha concentrations ranged from 0.0000238 to 0.00013 Bq/L, averaging 0.00008158 Bq/L, a value below the WHO limit of 0.5 Bq/L. Gross beta concentrations ranged from 0.536 to 2.78 Bq/L, averaging 1.7056 Bq/L, exceeding the WHO limit of 1.0 Bq/L. Radon levels varied from 0.12 to 1.7 Bq/L, averaging 1.102 Bq/L, below the WHO limit of 11.1 Bq/L. Annual effective doses from gross alpha ingestion were 4.10918E-05, 4.16874E-06, and 8.33748E-06 mSv/year for adults, infants, and children, respectively. Radon exposure doses were 1.61E-13 and 8.04E-14 mSv/year for adults and children, respectively, below the 0.1 mSv/year limit. However, beta radiation doses exceeded the 0.1 mSv/year limit, with values of 0.85911072, 0.21477768, and 0.42955536 mSv/year for adults, infants, and children, respectively. The average concentrations of heavy metals were 0.00058 mg/L for Cd, 0.012 mg/L for Cr, 0.00628 mg/L for Fe, 0.0046 mg/L for Mn, 0.09534 mg/L for Ni, 0.01214 mg/L for Pb, and 0.00582 mg/L for Zn. Children exhibited elevated cancer risks from heavy metal ingestion 0.004865 and dermal exposure 0.000069, with hazard quotient values of 0.740205 and 0.004882, respectively. The hazard index and lifetime cancer risk for children were 0.004882, exceeding USEPA recommended values. While gross alpha and radon levels were within safety limits, beta radiation levels and heavy metal hazard quotients exceeded maximum contamination levels, highlighting significant health risks, including DNA damage and increased cancer risks.

Determination of Structural, Electronic, and Elastic Properties of SnTiO3 using Density Functional Theory

2024-10-28T06:41:31+00:00

The harmful effect of lead Pb2+ base materials like PbTiO₃ on the environment and human health has raised ecological concerns, which has led to the investigation of lead Pb²⁺ free ferroelectric materials that are safe for the environment and human health and can be used in technological applications. In this research, the structural, electronic, and elastic properties of the cubic phase of SnTiO₃ were investigated using first principle calculation. The electronic structure calculation was done by using the generalized gradient approximation and PerdewBurke Ernzerhof (GGA-PBE) functional as implemented in the pseudopotential plane wave approach within the framework of density functional theory (DFT) by using Quantum Espresso open sources computer code. The convergence test of total energy concerning energy cut-off wave function and k-point sampling was performed to ensure the accuracy of the calculations. Thermo_pw code was employed to compute the elastic constant using the Quantum Espresso software package and the result obtained was used to calculate mechanical parameters such as the elastic properties, anisotropy factor A, shear modulus G, bulk modulus B, Young’s modulus E, and Poison’s ratio n of the SnTiO3. Furthermore, Debye temperature and longitudinal and transversal sound velocities were determined using the elastic constant. Therefore, the cubic phase of SnTiO₃ with a space group of (Pm3m) is a good ferroelectric material due to its Debye temperature and the covalent bonding nature of the atom within the solid crystal of the material.

Preliminary Assessment of Thermal and pH Properties of Soils in Ogoniland, Rivers State, South-South, Nigeria

2024-10-28T06:58:35+00:00

Soil temperature and its variations at different depths are unique parameters that contribute to the understanding of both surface energy processes and regional environmental conditions. This study reports the effects of oil and gas exploration (pollution) on soil thermal properties in Ogoniland, Rivers State, Nigeria. The scope of this study is limited to the determination of the temperature and pH of the soils. A total of thirty (30) soil samples were collected randomly using vegetation, slope, and altitude factors from three (3) local government areas of Ogoniland, Rivers State, Nigeria for determining the point for each sampling, coordinates, and elevation. Soil samples were collected at two depths: 0-15 cm (Topsoil) and 15 – 30 cm (Subsoil) with the aid of a Dutch stainless steel hand auger from four (4) sites (impacted) at different locations within the study area and one (non-impacted) control site outside the project area. A standard digital soil thermometer was employed to determine the temperature of the soils in situ in both regions. It has been observed that the pH and temperature of soils in situ and their variation with test points (location) agree with the results reported in these and similar environments. Hence, it can be concluded that the soils in Eleme, Gokana and Tai Local Government Areas may be recommended, but, with caution, for agricultural activity, laying of gas pipelines, or buried cable in the areas, since the values of these properties observed were within the range of standard values.

Plasmonic Photo-Electrode with AgNPs as Artificial Nano-Antenna for Enhanced Performance in Perovskite Solar Cells

2024-10-28T07:07:27+00:00

The introduction of noble metal nanoparticles in solar cells has been proven to enhance the performance of perovskite solar cells. In this study, silver-modified photoanodes were utilized to improve the performance of perovskite solar cells through successive ionic layer adsorption and reaction (SILAR) procedures. Due to the surface plasmon resonance effect, the light trapping capacity of the device was enhanced with superior photovoltaic properties. The plasmonic effects of the introduced silver nanoparticles (AgNPs) were explored using SEM, XRD, UV-visible absorption spectrophotometer and solar simulator. The SEM results show compact morphologies and shinning surfaces indicating the presence of AgNPs. The XRD result shows a good crystal phase. The UV-vis results show enhanced optical absorption with AgNPs incorporation. The photovoltaic characteristics of the fabricated PSCs are: (i) pristine device; Jsc of 6.440 mA/cm² , Voc. of 0.948 V, FF of 0.642 and PCE of 3.917%, (ii) device with 1 SILAR of AgNPs; Jsc of 014.426 mA/cm² , Voc. of 0.949 V, FF of 0.642 and PCE of 8.795%, and (iii) device with 2 SILAR of AgNPs; Jsc of 10.815 mA/cm² , Voc of 0.917 V, FF of 0.558 and PCE of 5.536%. The device with the best performance is made of 1 SILAR cycle of AgNPs which shows an enhancement of ~2.245 times in PCE, ~2.240 times in Jsc and ~1.001 times in Voc over the reference device. The results in this study have unlocked the beneficial role of AgNPs and further contribute to understanding surface plasmon effect due to AgNPs introduction.

Assessment of Radon Concentration in some Selected Water Sources at Kiyawa Town, Kiyawa, Jigawa State, Nigeria

2024-10-28T07:22:15+00:00

In this study, an assessment of Radon concentration in some selected water sources from Kiyawa town, Kiyawa local Government area, Jigawa state, Nigeria was conducted. The results obtained show that the concentrations of Radon in the water samples ranged from 32.152 to 43.891 Bq/L, with mean values of 37.78 Bq/L and 35.13 Bq/L for well and borehole water respectively. These results were compared with the world average Maximum Contaminant Level (MCL) of 10 Bq/L set by the World Health Organization (WHO), and it was observed that 60% of the recorded Radon concentrations, alongside the mean values for both water types, exceeded the WHO's recommended MCL of 10 Bq/L, as well as the MCL of 11.1 Bq/L set by the United States Environmental Protection Agency (USEPA) in 1991. However, all mean values were below the recommended action level of 100 Bq/L set by the European Commission (2001/928/ Euratom) for public water supplies, and WHO in 2008. Also, all the mean values of the annual effective doses exceeded the recommended level of 0.1 mSv/year set by the WHO. Consequently, it is recommended that the inhabitants of Kiyawa town boil their water, regardless of its source, before drinking to reduce Radon concentrations in the water.

Implications of Solar Wind Disturbances on Forbush Decrease

2024-10-28T08:30:35+00:00

This study investigated the role of solar wind disturbances on variations in cosmic ray intensity. To conduct the study, use was made of the data on cosmic rays from the SOPO, CLMX, and MOSC neutron stations, as well as solar wind speed data from 2000 to 2005. The source Forbush decrease (FD) dates were generated from onset journal publications, specifically the FD list of Dumbovi ́c et al., (2011). The manual method of FD selection was used to identify FDs. The FD dates, computed magnitudes, and solar wind speed data were recorded and presented. From the study, FDs were generated, some of which were of the same date as those in the source table, while others were not observed in the source table. FDs not observed in the source table were generated and catalogued by this research. It was also observed that the magnitude of FDs generally depends on the coordinates of the observing neutron stations. A strong correlation with a value of cc = 0.93 was observed between FDs of SOPO and MOSC stations, followed by FDs of CLMX and MOSC stations of value cc = 0.89, and lastly, FDs of SOPO and CLMX stations of value cc = 0.74. This implies that observed FDs from neutron stations are coordinate-dependent. The correlation between FD magnitudes and solar activities shows that solar wind had a high and significant correlation with FD magnitude to the tune of cc = 0.54. Based on the findings, the study concludes that solar wind disturbances play a crucial role in causing a sharp decrease in the intensity of cosmic rays known as Forbush decrease.

First Principle Study of Structural, Electronic, Mechanical and Optical Properties of Bulk Niobium Dichalcogenide NbX₂ (X=S, SE) within a Visible Phonon Energy Range

2024-10-28T07:47:08+00:00

An intensive study on structural, electronic mechanical and optical properties of bulk Niobium Dichalcogenides NbX₂ (X=S, Se) was carried out using the first principle. The structural parameters such as Equilibrium Lattice Parameters, Volume, Bulk Modulus, and FirstDerivative Modulus were calculated to determine if the materials are energetically stable. Elastic constants were further obtained from which mechanical properties i.e. bulk, Young's and shear moduli and consequently Poisson's ratio were obtained. Based on the well-known Born stability conditions Bulk-NbS₂ is most likely mechanically anisotropic ductile material. While Bulk-NbSe₂ for the predicted B/G ratio in all three methods is less than a critical value of 1.75, hence this shows that NbSe₂ is a brittle material exploring its electronic and optical properties whose motivation was to find out the most stable phase and ascertain if these materials could be used in various fields that suit their mechanical and optical properties. Furthermore, from the calculated optical spectra, plasma frequencies were analyzed which indicated the possibility of applying the material in plasmonic-related fields.

Assessing Ionizing Radiation Exposure Risks to Human Health in Wadi-B, Jere Oil Exploration Areas, Borno State, Nigeria

2024-10-28T07:58:56+00:00

Ionizing radiation, emanating from decaying nuclides, poses potential biological harm to human organs. Wadi B, a village within the Jere local government area of Borno State, Nigeria, is currently undergoing oil exploration activities. This study was conducted to evaluate the outdoor gamma radiation levels at the Wadi B oil exploration site. Utilizing a portable hand dosimeter (Radiation Alert Inspector), gamma exposure levels (GEL) were measured across sixteen (16) spots within the exploration site. Results revealed that the gamma exposure levels measured in the boreholes FYM (1 to 8), range from 0.17- 0.27 Mr/hr, with an average of 0.21 Mr/hr while, the levels around the wells FYM (9 to 16) vary from 0.14- 0.25 Mr/hr, with an average of 0.18 Mr/hr. The estimated annual effective dose (AED) varied from 0.24528 to 0.47304 μSv/yr, averaging at 0.3460 μSv/yr. Notably, the average values of Total Dissolved Solids (TDS), Conductivity, and Gamma radiation exceeded the recommended limits established by the World Health Organization (WHO, 2006), which are 400 μS/cm for conductivity, (50-150) ppm for TDS, and 0.002 mR/hr for radiation doses, respectively. However, the calculated Excess Lifetime Cancer Risk (ELCR) values were lower than the proposed world average level of 70 μSv/yr by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). This study suggests a heightened risk of exposure to outdoor ionizing radiation among inhabitants residing near the study locations.

Assessment of Natural Radioactivity and Radiation Hazard in Soil and Rock Samples from Mining Sites within North-Eastern Nigeria

2024-10-28T08:10:33+00:00

There have been potential public health risks associated with the use of soil and rock from mining locations in North-Eastern Nigeria. This research evaluates the natural hazard parameters of soil and rock specimens obtained from mining locations in North-Eastern Nigeria, using grammar-ray spectroscopy. A total of twenty-eight samples were systematically gathered from Nahuta and Kashere locations. Through gamma spectrometry employing a NaI (TI) detector, the natural radioactivity levels of 238U, 232Th and 40K were determined for each sample. The findings indicated that the mean activity concentrations of 226Ra, 232Th, and 40K in Nahuta are 46.13±4.78 Bq/Kg, 34.10±3.02 Bq/Kg and 473.94±5.41 Bq/Kg for the soil samples respectively, and 32.91±0.49 Bq/Kg, 40.70±0.41 Bq/Kg, and 578.18±4.28 Bq/Kg for the rock samples respectively. The corresponding mean activity concentrations of 226Ra, 232Th, and 40K in Kashere are 17.99±4.18 Bq/Kg, 23.73±1.78Bq/Kg, and 191.65±3.15 Bq/Kg, for the soil samples, and 20.24±3.72 Bq/Kg, 29.09±1.78 Bq/Kg, and 148.36±3.15 Bq/Kg, for the rock samples respectively. An analysis of radiation risk parameters (D, AEDE, Raeq, Hex, Hin, AGDE, and ELCR) has been explored. While the samples from the Kashere region fall within the international recommended levels, elevated readings of certain radiation health parameters are observed in the Nahuta region, posing serious public health risks due to the utilization of the soil and rock from this area in construction activities.

First Principle Investigations of Structural, Electronic and Thermal Properties of Pristine, Metal and Non-Metal Doped Silicene for Thermoelectric Applications

2024-12-12T04:40:00+00:00

Silicene, a two-dimensional hexagonal silicon layer, exhibits exceptional electronic and thermoelectric properties. However, its application in semiconductors is hindered by its zeroband gap, which could be overcome by modifying its electronic properties through doping. In this paper, Density Functional Theory (DFT) calculations were performed to investigate the band gap opening in silicene by studying the effect of magnesium and sulphur doping on its electronic, structural and thermal properties. Pristine silicene has a lattice constant of 3.86 Å and a zero-band gap. Upon doping with 12.5% S and Mg atoms, the lattice constant modifies to 3.45 Å and 3.93 Å, respectively, resulting in a direct band gap opening. For 25% Mg and S doping, the result shows that Mg and S effectively alter the band structure and the band gap of silicene monolayer at various configurations. The maximum band gap was 0.98 eV and 1.22 eV for Mg and S doping into the meta position to the reference point R, respectively. The power factor significantly increases with doping, reaching 1.20 x 1011 WK-2m-1 and 1.40 x 1011 WK2m-1 for 12.5% Mg and S doping compared to 7.4 x 1010 WK-2m-1 for pristine silicene. This substantial enhancement indicates improved thermoelectric performance, making silicene a promising candidate for thermoelectric applications. Results demonstrate that tuning the band gap through doping can simultaneously enhance the power factor, highlighting the potential of Mg/S-doped silicene for efficient energy harvesting and conversion.

Radiological Risk Assessment of Building Materials Used in Federal College of Education (Technical) Akoka, Lagos State, Nigeria

2024-12-12T04:48:02+00:00

Multiple building constructions necessitating a regular influx of different soils for building purposes within Federal College of Education (Technical) Akoka, in Lagos State, Nigeria spurred a radiological risk assessment of selected soil samples. Five (5) construction points were identified and ten (10) soil samples were collected. A gamma spectrometer was used to evaluate the natural radionuclides (226Ra, 232Th, and 40K) present in the soils. IAEA-certified standard materials of RGU^-1, RGTh^-1, and RGK^-1 were used to determine the full peak efficiencies of gamma energies 609, 1120, and 1764 keV for 238U, 2614 keV for 232Th and 1460 keV for 40K. Activity concentration, absorbed dose, annual effective dose equivalent, hazard indices, and excess lifetime cancer risk (ELCR) were estimated to assess possible radiological risks in the building soil samples. Results from the analysis revealed the highest radioactivity among soil samples was 674.3 Bq/kg from 40K and the lowest was 18.5 Bq/kg from 226Ra. The absorbed dose (D) varies from 65.8 nGy/h to 215.3 nGy/h with an average value of 136.6 nGy/h, and the annual effective dose equivalent ranged from 0.081 mSv/y to 0.264 mSv/y with an average value 0.168 mSv/y. The internal and external hazard index ranged from 0.49 −1.46 and 0.39 − 1.32 respectively which is not completely below the hazard index threshold value ≤ 1 as recommended by UNSCEAR. The ELCR values ranging from 0.222 × 10^-3 − 0.726 × 10^-3 with an average value of 0.461 × 10^-3 predicted an insignificant carcinogenic risk with the probability of four persons in every 10,000 persons.

Assessment of Activity Concentration and Health Hazards of Radiation Exposure in Soil from Mamara Jidda and Waja Tin Mining Sites in Northern Nasarawa State, Nigeria

2024-12-12T05:07:20+00:00

Natural background radiation exposure is an inevitable occurrence on Earth, and humans are exposed to radiation in their surroundings whether consciously or unconsciously. However, increased artisanal and illegal mining could harm the local environment and increase background radiation levels, affecting the community's overall health. This study assessed the activity concentration of primordial radionuclides (226Ra, 232Th, and 40K) from soil samples obtained from Mamara Jidda and Waja tin mine sites in Nasarawa State, Nigeria, and its risk to human health. The gamma spectroscopy using a Sodium iodide-thallium activated detector was used to measure the activity concentrations of primordial radionuclides in the surface soils/sediments samples. The activity concentrations of 226Ra, 232Th, and 40K for Mamara Jidda and Waja were found to be within the range of 4 - 18 Bq kg^-1 , 41 - 105 Bq kg^-1 , and 524 - 717 Bq kg^-1 ; 13 - 40 Bq kg^-1 , 75 - 134 Bq kg^-1 , and 591 - 882 Bq kg^-1 respectively. The average values show that 40K and 232Th concentrations are above the recommended limit set by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) in Mamara Jidda and Waja mine sites. The annual gonadal dose equivalent (AGDE), annual effective dose rate (AEDE), radium equivalent (Raeq), absorbed dose rate (D), and external hazard index (Hex) for Mamara Jidda and Waja were found to be 0.56 mSv yr^-1 , 0.10 mSv yr1 , 588.58 Bq kg^-1 , 78.26 nGy hr^-1 and 0.46; 0.73 mSv yr^-1 , 0.13 mS yr^-1 , 742.74 Bq kg^-1 , 103.72 nGy hr^-1 and 0.61 respectively. The AEDE and Hex are below the recommended safety limits. However, the high values of AGDE in both mining sites and D in Waja mine demonstrate that with continuous exposure to radiation, a significant genetic impact is eminent to the miners and inhabitants of these areas. Also, the Raeq values for both mines suggest that their soils are unsafe for use as building materials.

Assessment of Trace Elements Concentration in Selected Vegetables from High and Low Cancer Prevalence Areas in Ondo State, Nigeria

2024-12-12T05:22:17+00:00

This study investigates the potential link between cancer incidence and trace elements and heavy metals intake from locally grown vegetables in Ondo West and Ondo East Local Government Areas of Ondo Stae, Nigeria. It builds on a 2019 study by Adeola and colleagues, which identified a significantly higher cancer incidence in Ondo West compared to Ondo East, with rates three times higher. Five commonly consumed vegetables—Solanum macrocarpon, Talinum triangulare, Amaranthus hybridus, Telfairia occidentalis, and Vernonia amygdalina— were sampled from 47 locations across both regions. The samples were oven-dried, digested, and analyzed using atomic absorption spectroscopy (AAS) to determine the mean concentrations of essential trace elements (magnesium, manganese, and zinc) and toxic heavy metals (lead and cadmium). The estimated daily intake (EDI), daily intake (DI), and chronic daily intake (CDI) were calculated and used to assess the incremental lifetime cancer risk (ILCR), non-cancer hazard quotient (HQ), and non-cancer health index (HI). Contributions to the recommended daily intake of magnesium, manganese, and zinc through vegetable consumption were 12.65%, 40.8%, and 9.6%, respectively, in Ondo West, and 13.7%, 47.7%, and 10.58%, respectively, in Ondo East. The total non-cancer health indices were 0.90 and 0.92 for Ondo West and Ondo East, respectively, indicating no significant non-cancer health risks from consuming these vegetables. However, the ILCR values were calculated as 0.000293 for Ondo West and 0.000416 for Ondo East, exceeding the threshold of 1.0 × 10⁻⁵, suggesting a potential cancer risk. Despite this finding, the study could not account for the notably higher cancer prevalence in Ondo West.

Delineating Potential Hydrocarbon Targets Through Aero-Radiometric Techniques

2024-12-12T05:31:47+00:00

The discovery of more hydrocarbon wells remains a major recipe to boost the economy of Nigeria, a major oil producer in Africa. The seismic method is prominent for identifying traps in the oil explorations, but cannot indicate if the trap host hydrocarbon. This gap is usually filled by the radiometric method, its characteristics around the Kolmani well 1 have hitherto not been reported. This research focused on identifying promising locations for hydrocarbon accumulation around the Kolmani Well 1 while using the well as a control. To achieve the objectives of this research, the nature of the radioelements was observed over the Kolmani well1 and the outcome of normalizing potential and uranium was also identified. The average values of potassium (K), thorium (Th), and uranium (U) are 0.277%, 8.917 ppm, and 1.431 ppm respectively. The concentration of the three radioelements, K, Th, and U, decreases over the oil well. This was ascribed to enhanced leaching of natural radioelements caused by hydrocarbon-generated groundwater acids. The result of the normalization of K with Th yields a low concentration of K over the Kolmani well1 and the normalization of U with Th yields a high concentration of U over the Kolmani well1. These were in tandem with the report on the application of the method in previous locations. Hence, the results of the normalization of K and U were used to identify four locations with potential for hydrocarbon exploration. The viability of these locations was confirmed with the positive DRAD (Delineation of Radiometric anomalies) value (ranging from -5.1 to +5.2), a pointer to hydrocarbon accumulation in an area, recorded in these locations and the location of the Kolmani well 1.

Investigating the Impact of Voltage on Optoelectronic Features of Silver Incorporated into the Lattice of Zirconium Sulphide Nanostructured Material

2024-12-12T05:42:16+00:00

This research aims to enhance the optoelectronic properties of Ag-doped ZrS through electrochemical deposition. Different characterization techniques were employed to examine the optical, structural, and morphological properties of the synthesized material, with results showing that the absorbance of ZrS and Ag-doped ZrS changes with the applied voltage, enhancing carrier concentration and mobility at higher voltages to enhance absorption properties. ZrS displays a bandgap energy of 2.00 eV, showing its potential as a semiconductor material, while Ag-doped ZrS results in higher bandgap energies between 2.15 eV and 2.50 eV, leading to modifications in its electronic characteristics. The crystal planes of 101, 103, 111, and 112 are identified by precise 2θ angles of 23.59°, 34.91°, 48.42°, and 62.62° for ZrS and 19.64°, 33.61°, 44.48°, and 63.31° for Ag-doped ZrS. Altering voltages (10, 12, 14 V) affect the electrical structure in XRD analysis, influencing peak positions and intensities. A more evenly distributed Ag layer, preserving surface smoothness, results from lowering the voltage while introducing Ag. The interaction of Ag and ZrS leads to localized structural changes. As the voltage increases, the surface roughness of Ag-doped ZrS increases more than the undoped ZrS. The resistivity values decrease as the voltage increases, suggesting enhanced conduction and more charge carriers. The increased conductivity values (4.34, 4.58, 4.71 and 4.78 S/m) indicate that higher voltage enhances conductivity, benefiting applications needing efficient charge transfer.