An electrical resistivity investigation was carried out in parts of the College of Education
(Technical) Asaba to delineate the subsurface lithologic units with special emphasis on the competence and suitability for engineering foundations. A total of ten (10) vertical electrical
sounding and two (2) horizontal profiling stations were covered within the study area using the
Schlumberger and dipole-dipole configurations. The acquired data was analyzed using WinResist and RES2DINV Software; the subsurface within the study area is composed of mostly 3 geoelectric layers: topsoil, clay/sandy clay/clayey sand and sand. The second and third
layers have relatively low resistivity ranging between 29 – 94 Ωm and consist of incompetent clayey material underlying about 60 % of the investigated study area. The interpreted field results showed a significant clay overburden that is over 5 m thick. A fourth layer of sand with resistivity values ranging between 451 – 1258 Ωm was encountered at depths between 4.9 – 11.5 m; the thickness of this layer with reference from the borehole log is greater than 20 m. It is therefore recommended that the incompetent clayey material be avoided or excavated before
constructing any structure.
This study examined the levels of metals (Mg, Al, Si, P, S, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Zr, Nb, Mo, Ag, Sn, Sb, Ta, Pt, Au, Pb, and Bi) in onion bulbs and leaves in light of the latent toxicity, unsolvable character, and snowballing behaviour of heavy metals. The onion bulbs and leaves were randomly selected from the Samaru market chopped, dried, and ground
into a powder for X-Ray Fluorescence Spectrometer (XRF) measurement. Except for
concentrations of Si, Ti, Zr, and Ag, with the value of 9.996, 4.051, 2.047 and 2.082 mg/kg in
the onion bulbs and 20.23, 5.861, 1.175 and 1.538 mg/kg in the onion leaves respectively,
which were higher than the permissible level of 0.800, 0.530, 0.000005 and 0.014 respectively,
all the metals analysed were at or below the World Health Organization's (WHO) permissible
limit. The findings generally indicated that Si, Ti, Zr, and Ag poisoning could result from eating onion bulbs and leaves from the Samaru market due to the Si, Ti, Zr, and Ag health risks. To avoid metal poisoning and subsequent bioaccumulation of the metal in the systems of
consumers and the ecosystem at large, there is a need for a quarterly examination of the metal content in the onion bulb and onion leaf in the Samaru market.
The physical properties of crystalline compounds are highly essential for predicting their
applications in various nanodevices. Density functional theory is very useful in that regard.
Herein, some physical properties such as structural stability, and electronic, optical and
mechanical properties of two-phase bulk WSe2 have been comparatively investigated by first
principle calculations. Band structure calculations elucidate that the materials are indirect band
gap semiconductors having band gap energy in the range 1-1.5 eV. It was observed that the
hexagonal crystal has higher absorption coefficients compared to the trigonal phase. Analysis
of elastic constants of the materials carried out using the Born criteria method indicates that all
systems are mechanically stable at room temperature. Our findings are in close agreement with
the previous experimental and theoretical results, this further suggests that the materials are
promising in optoelectronics applications.
A geophysical study has been carried out using the electrical resistivity method, Very LowFrequency Electromagnetic (VLF-EM) and physiochemical analysis to investigate the effects
of groundwater contamination in the vicinity of an open dumpsite at Idugosa. A Vertical
Electrical sounding was carried out at 100 m away from the dumpsite and the results revealed
an H-type curve with 3- layers, with a low resistivity value of 90.0 Ωm, thickness of 9.8 m and
depth of 11.3 m at the weathered basement. The control VES revealed 5 –layers of HK-type
curve. The resistivity of the weathered and fractured basement ranged from 241.8 Ωm to 2908.4
Ωm with a thickness range of 3.5 m to 13.6 m and a depth range of 5.6 m to 19.1 m. Results
of the horizontal profiling using Wenner profiling revealed a low resistivity value of 1.6 Ωm to
3.8 Ωm at a depth of 15 m to 30 m, concentrated at stations 20 to 100. The bottom of the western
part showed that the leachate plume had infiltrated and contaminated the groundwater in the
zone. The VLF-EM with the three profiles revealed high current density values on the KarousHjelt filter plot at distances of 20 m to 38 m for profile 1, 25 m to 50 m and 75 m to 95 m for
profile 2, revealing the presence of contaminants which is mainly from decayed organic matter
from waste bodies and heavy metals from the dumpsite. Profile 3 which is further away from
profile 1 revealed that the contamination is reduced as we move further away from the dumpsite
at about 10 m to 20 m, 50 m to 60 m and 90 m respectively. The physio-chemical analysis
results showed a pH range of 6.73 – 7.17 which is within the World Health Organization
(WHO) standard (6.5 - 8.5). The Electrical Conductivity (EC) value of the Idugosa dumpsite
was found to be 804.9 μS/cm, which is above the WHO standard for EC values, which should
not exceed 400 μS/cm. This high value can be attributed to the infiltration of the leachate plume
from the dumpsite. The EC for Idugosa control which is 188.0 μS/cm is within the WHO limit
for groundwater, thus its safe for consumption.
Kidney failure has become a growing problem at Hadejia Emirates over the last decade. This can be attributed to water pollution, possibly due to heavy metal contamination of River Hadejia that affects organisms living in it, such as fish. This study is aimed to determine the
concentration of heavy metals (As, Cd, Cr, Pb) in two fish muscles. The research was conducted on tilapia and catfish where two samples of both fishes were used. The fish tissues were cut and oven-dried at 110 °C, and then a motor and pestle were used to powder the dried fish
sample. A wet digestion method was used based on the analytical methods for Atomic
Absorption Spectrometry (AAS). The result obtained shows that the concentrations of heavy
metals (Cr, Cd, As and Pb) in both fishes were found to be 0.3220 ± 0.0028; 0.1656 ± 0.002
(𝑚𝑔/𝑘𝑔), 0.0319 ± 0.0018; 0.0333 ± 0.0018 (𝑀𝑔/𝑘𝑔), 0.0697 ± 0.0011; 0.1035 ± 0.0015
(𝑚𝑔/𝑘𝑔) and 1.008 ± 0.0035; 0.600 ± 0.002 (𝑚𝑔/𝑘𝑔) respectively. The mean concentration value of the two samples of both tilapia and catfish were found to be above WHO standard limit except for cadmium in tilapia which is below WHO standard limit.
Borate glass systems have been extensively studied for practical applications in optical display
devices by virtue of their peculiar luminescence efficiency. However, the attainment of high
emission from borate glass materials via apposite control of rare earth ions (REIs) contents
remains a topical issue in Material Physics. In this paper, we report the influence
of REIs (Dy3+, Eu3+, and Sm3+) on multiple-colour emission of magnesium sodium borate
(MSB) glasses fabricated by using the conventional melt-quenching method. These glasses were optically characterized via X-ray Diffraction (XRD), UV-VIS-NIR and
Photoluminescence techniques. The XRD pattern confirms the amorphous nature of the as-prepared glasses. The absorption spectra disclosed several absorption bands at 347 nm (6H15/2 → 6P7/2) for Dy3+, 393 nm (7F0 → 5L6) for Eu3+ and 403 nm (6H5/2 →6P5/2) assigned for Sm3+ respectively. Also, the emission spectra radiate at 463 nm (4F9/2 → 6F11/2 + 6H9/2), 612 nm (5D0 → 7FJ) and 599 nm (4G5/2 → 6H7/2) for Dy3+, Eu3+, and Sm3+ correspondingly, wherein Dy3+ emits blue, yellow, and red light, Eu3+ emits red light and Sm3+ emits reddish-orange light. Finally, 1.0 mol% content of Dy3+, Eu3+, and Sm3+ in MSB glasses was found to be optimal and hence considered the best optical host for colour display devices.
A study of the occurrence of the first intense Geomagnetic storm (G4) to hit the Earth since the
start of the Solar Cycle 25 is carried out. This study analyzed the Geomagnetic Storm that
occurred between the 28th of October and the 7th of November 2021. The values of the
Disturbance storm time (Dst) index of the storm reach -115 nT (G4) which occurred on the 4th
of November at 1300UT. The storm is the first intense magnetic storm that occurred in the solar
cycle 25. It is also a multiple-step storm with moderate two-step storm occurrence which
occurred on the 5th and 6th of November at 1500UT and 0600UT respectively towards the
recovery phase after the intense storm. The interplanetary magnetic field (IMF)Bz (nT) during
these storm events decreases. Our analysis shows that the rise in solar wind speed, temperature
and the enhancement of pressure plays a significant role in the occurrence of the first intense
Geomagnetic storm of Solar Cycle 25.
This study identified the fluid types and boundaries present within selected reservoirs in Langbodo field, using petrophysical parameters based on estimated rock properties such as porosity, permeability, irreducible water saturation, hydrocarbon saturation and bulk water volume. This was with a view to correcting the salient reservoirs heterogeneities anomalies error inherent in building of an ideal realistic reservoir models. The quality of the data obtained were checked and despiked to eliminate null values. Petrel version 2009 and OpendTect 4.6.0. Exploration and production softwares were used for the quality interpretations of data, such as lithology identification, delineation of potential reservoirs and determination of fluids and fluids contacts. Estimation of quantitative petrophysical parameters were done by inputting the data into Microsoft excel 2015 version softwares and adopting appropriate mathematical relations, such as the Tixier, Timur and the Coates and Dumanoir models for the permeability (K). Realistic estimation of the permeability was done by comparing the average of the Tixier, Timur and the Coates and Dumanoir models with each of the models. The composite model obtained, mirrors the behavior of the Timur’s permeability which is higher than that of the Tixier and the Coates and Dumanoir. Integration of the Achie’s equation and neutron – density crossplot confirmed the presence of substantial hydrocarbon in the reservoirs, although producibility indicators revealed that the reservoirs may not be producible without enhanced oil recovery method(s). This study established that the composite model is a better representation of K in the study area because it agrees with the Timur’s estimation model.
The methyl ammonium tin iodide (Ch3Nh3SnI3) perovskite nanocrystals have attracted research interest and have become a rising star in the horizon of photovoltaics due to its narrow band gap, wide visible absorption coefficient and environmental friendliness than its lead-based counterpart (Ch3Nh3PbI3) . In this article, a tin based perovskite solar cell with Zinc oxide (ZnO) and Copper Oxide (CuO) as electron transport medium (ETM) and hole transport medium (HTM) was proposed and investigated numerically using a Solar Cell Capacitance Simulator (SCAPS) tool. With appropriate parameters, a short-circuit current density (Jsc) of 27.56 mA/cm2, open-circuit voltage (Voc) of 0.82 V, fill factor (FF) of 59.32 %, and power conversion efficiency (PCE) of 13.41 % are obtained for the initial simulation. By varying the thicknesses of the absorber and electron transport layer, the optimum thicknesses were observed at 0.6 um and 0.3 um for Ch3Nh3SnI3 and ZnO with corresponding PCEs of 14.36 % and 13.42 %. Upon simulation with optimized parameters, a Jsc of 29. 71 mA/cm2, Voc of 0.83 V, FF of 61.23 % and PCE of 15. 10 % were recorded. These values are superior to those obtained without optimization which means that solar cell performance can be improved to some extent by adjusting the perovskite and electron transport layer and also, Ch3Nh3SnI3 Perovskite solar cell (PSC) is a potential environmentally friendly solar cell with considerable efficiency.
This study aimed to estimate the depth of Nickel deposit in Bakin Kogi – Dangoma region, which lies between latitude 901''and 9027'N and longitude 8000' and 8017' E. The study area is located in Jema’a local government area of Kaduna state. The data was gridded using Oasis Montaj® to produce Total magnetic Intensity Map (TMI) of the area, and further subjected to some filtration processes in order to obtain regional and residual map of the study area. Enhancement methods such as first vertical derivative and analytic signal methods were applied to the residual map to delineate the area with potential Nickel deposit. The quantitativemethod applied were source Parameter Imaging and Euler Deconvolution to determine the various depths of Nickel deposit. From the results of the TMI map and the residual map, the magnetic intensity of the study area was between 32976.5 to 33093.3 nT and 32963.6 to 33072.9 nT respectively with Bakin kogi-Dangoma region, having the highest magnetic intensity of about 33093.3nT and 33072.9 nT respectively. The study area has a high magnetic intensity due to nickel deposit because Nickel ore environment are notable with recognizable “magnetic stratigraphy”, prospective mafic-ultramafic contact, typified by strong magnetic contrast. Abrupt changes in the magnetic intensity infer position of the outer contact of a Nickel bearing zone. The results on the superimposed analytic map on the lineament map showed regional lineaments in Bakin kogi-Dangoma region trending NE -SW, ENE – WSW and NNE – SSW directions. The fractures and faults seen around the study area were strongly associated with minerals deposit. The results of Source Parameter Imaging (SPI) gave a depth of shallower magnetic sources ranges from 92.7 to 116.0 m with an average depth value of 104.35 m while the depth of deeper magnetic sources ranges from 651.2 to 976.2 m with an average depth of 813.7 m. The results obtained from 3D Euler deconvolution which was associated with dykes (SI = 1) anomaly produced at a shallower depth range of 100 - 700 m. Results obtained, shows a correspondence between the depths results obtained from the SPI and that of the Euler Deconvolution methods, indicating correlation in the magnetic depth estimation.
The study of shear rheology and molecular architecture through molecular dynamics simulation
of starch-based and gelatin-based adhesives formulated from Eleusine coracana, and cow hide
has been successfully achieved. This research has revealed that esterification of natural dextrins
with 20 % polyvinyl acetate (PVAc) will yield adhesives product with improved gel properties suitable for applications. Method of extraction, production of the adhesives by varying the
quantity of fatty acid ester and quality assessment was performed and 20% PVAc incorporation found to be suitable for application. The physical features of the macromolecular complexes
formed by the synergistic interaction of starch/gelatin and PVAc in the presence of
tetraethylamine (TEA) has been studied from the rheological point of view. On examining the impact of the molecular structure and electronic properties of the adhesive molecules on the
adhesive efficiency, quantum chemical calculations were carried out. Rheological analysis
shows the adhesives are consistent and the computed free energy obtained from molecular dynamics simulation reveals that the adhesive molecules are spontaneous, hence efficient.