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1.
Heliyon ; 10(10): e31308, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38826710

RESUMO

Engineering geological characterizations, and geophysical mapping of subsurface structures to monitor some susceptible infrastructural facilities to hazardous slopes for effectiveness, safety to lives and properties, in addition to policy management for sustainable development. Novel integrated engineering geology, geoelectrical resistivity (ER), and borehole data analysis, to characterize subsurface for slope instability, determining critical zones prone to hazardous slopes in Peninsular Malaysian (PM), east coast areas was focused on. Engineering Laboratory soil investigations using disturbed and undisturbed samples collected to obtain firsthand information on the subsurface soils, and rocks physical properties, integrated with ER data to obtain subsurface geoelectric profiles. Regions delineated as loose and marked as water saturated residual soils prone to slopes corresponds to ER values < 100 Ω-m. ER values between 100 ≥ 500 Ω-m, were delineated as residual soils zones devoid of water contents. Subsurface geoelectric profiles related to hard materials were delineated as weathered and fractured bedrock zones corresponding to ER values between 500 ≥ 2000 Ω-m. Granitic bedrock units delineated as subsurface lithological zones with ER values > 4000 Ω-m. Slope Mass Ratings (SMR), was carried out to construct suitability, and slope assessment system (SAS) model ratings map for the four classes obtained.

2.
Heliyon ; 10(2): e24658, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38304827

RESUMO

The 3-D Bohr-Mottelson Hamiltonian for γ-rigid prolate isotopes is solved via inverse square potential having only one free parameter, ß0. The exact form of the wave functions and the energy spectra are obtained as a function of the free parameter that determines the changes in the spectra ratios and the B(E2). The solutions are compared with the X(5) model and some new set of equations that show the relationships between the two models are stated. The entire solutions from ß0=0 to ∞ are compared with U(5), X(5) and SU(3). The solutions spread from the region around U(5) over X(5) and approach SU(3) at ß0=∞. The exact solutions obtained via variational procedure are compared with some existing X(3) models in the literature. The strong agreement between the present model and X(3) via infinite square well potential is discussed. Twelve best critical point isotopes, 102Mo, 104-108Ru, 120-126Xe, 148Nd, 184-188Pt are chosen for experimental realization of the model and moderate agreements are recorded. An excellent agreement which appears in the first ß-excited state in the comparison of the present model with three N=90 isotones: 150Nd, 154Gd, and 156Dy, known to be X(5) candidates, suggests that the present model compensates the X(5) models whose predictions are excellent in the ground states but moderately bad in the first ß-excited states.

3.
MethodsX ; 10: 102201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37181849

RESUMO

This study evaluates the causes, concentration and the associated health risks of selected heavy metals (HMs) in soil samples collected from beryllium and gold mining fields in Nigeria. The samples of soil were collected manually and analysed by means of Atomic Absorption Spectrophotometry (AAS). Seventy-two (72) samples were analysed which presented varying degrees of concentration of the selected HMs. The analysed HMs are Chromium (Cr), Arsenic (As), Iron (Fe), Cadmium (Cd), Nickel (Ni), Manganese (Mn), Magnesium (Mg), Zinc (Zn), Copper (Cu) and Lead (Pb). Deterministic and stochastic approaches were explore to examine the human health risks. The evaluated Hazard Indices (HI) for the investigated mining locations are < 1, the recommended threshold provided by United State Environmental Protection Agency (USEPA) for acceptable non-cancer risk. The estimated cancer risk levels for the mining locations exceeds the acceptable range of 1.00E-6 and 1.00E-4.•Thus, the mining is making significant contribution to HMs pollution, which is dangerous human health.•However, the Monte Carlo simulation (MCS) reveals that the 95th, 50th and 5th percentiles of the cumulative probability of the cancer risks are within the acceptable range.•This work will be useful for decision makers in mitigating heavy metals contamination due to mining activities.

4.
Heliyon ; 9(3): e13710, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36851956

RESUMO

Understanding of the climate-water nexus for sustainability, required good knowledge of the climate effects on groundwater aquifer units, particularly in rural communities. The studies were achieved using RES2-D modelling of the subsurface structures at the study site. Geophysical exploration with the application of 2-D Electrical Resistivity Imaging (ERI), combined with Induced Polarization (IP) method, were carried out to identify groundwater aquifers during extreme weather at Kampung Kuala Pajam, Beranang, Selangor, Peninsular Malaysia. The signatures obtained from geophysical explorations were used to better understand the phenomena that are responsible for groundwater depletion in the area. In recent times, there had been seasonal fluctuations in the water supply from boreholes serving the community. During the drought season, subsurface underlain this area experienced perennial acute shortages of groundwater supplies due to annual climatic variations that call for immediate solution by meeting the agricultural, domestic, and industrial water usage of the State of Selangor. A Pole-dipole techniques, using seven parallel lines of 400 m each at 5 m inter electrode spacing deployed to study the groundwater accumulation/aquifers within the area. Saturated groundwater occurrences zones were delineated as areas with average resistivity values of about 125 Ω-m, with corresponding chargeability of 30 ms. The methods used identified major faults along the northeast-southwest (NE-SW) directions, suitable for groundwater occurrences with approximate volume of about 2.86 Mega cubic metre (CBM), to proffer lasting solutions to the challenges being experienced by the community using a climate-water nexus sustainability.

5.
Heliyon ; 8(11): e11534, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36411904

RESUMO

One of the major route through which humans are exposed to ionizing radiation is via food chain, which is consequent of soil-to-plant transfer of radionuclides. This work reported the activity concentrations of 40K, 238U and 232Th in samples of water, soil and guinea corn grains collected from Beryllium and Gold mining sites in Kwara, Nigeria. In-situ measurements at approximately 1 m in the air was carried out using a well-calibrated portable Gamma Spectrometer (Super Spec RS-125), while the soil, water and the guinea corn samples were analyzed using a '3 × 3' inch lead-shielded NaI (Tl) detector. The measured activity concentrations of the natural radionuclides in the soil from both mines are lower than the in-situ measurements. This was attributed to the contribution from other terrestrial materials on-site. The estimated mean transfer factors (TFs) for 40K, 238U and 232Th are 0.21, 0.17 and 0.31, and 0.46, 0.19 and 0.28 respectively for the Beryllium and Gold mining sites. While the TFs for 238U and 232Th exceeded the mean value of 0.0062 and 0.0021 for 238U and 232Th respectively, the TFs for 40K are well below the 0.74 for cereals grains provided by International Atomic Energy Agency (IAEA). The radiation impact assessment using the Monte Carlo simulations reveals values that were generally less than the global average values provided by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Hence, the risk of cancer inducement due to radiation exposure is within the acceptable limits for both mining sites.

6.
MethodsX ; 8: 101182, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33365262

RESUMO

A novel methodological approach was developed to quantified the volume of industrial waste desposal (IWD) site, combined with municipal waste materials (MWM), through the integration of a non-invasive, fast, and less expenssive RES2-D Electrical Resistivity Technique (ERT), using Wenner-Schlumberger electrode array geophysical method with Oasis Montaj software. Underground water bearing structures, and the eco-system are being contaminated through seepage of the plumes emanating from the mixtures of the industrial waste materials (IWM), made of moist cemented soil with municipal solid wastes (MSW) dumped at the site. The distribution of the contiminant hazardous plumes emanating from the waste materials' mixtures within the subsurface structural lithological layers was clearly map and delineated within the near-surface structures, using the triplicate technique to collect samples of the soil with the waste mixtures, and the water analysis for the presence of dissolved ions. The deployed method helped to monitor the seepage of the contaminant leachate plumes to the groundwater aquifer units via the ground surface, through the subsurface stratum lithological layers, and hence, estimation of the waste materials' volume was possibly approximated to be 312,000 m3. In summary, the novel method adopted are as presented below:•The novel method is transferable, reproduce-able, and most importantly, it is unambiguous technique for the quantification of environmental, industrial and municipal waste materials.•It helps to map the distribution of the plumes emanating from the waste materials' mixtures within the subsurface structural lithological layers that was clearly delineated within the near-surface structures underlain the study site.•The procedure helped in the monitoring of leachate contaminants plumes seepages into the surface water bodies and the groundwater aquifer units, via the ground surface, through to the porous subsurface stratum lithological layers.

7.
J Hazard Mater ; 406: 124282, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33199149

RESUMO

Environmental hazards, industrial, and municipal wastes geochemical and geophysical assessments were carried out at an industrial waste disposal (IWD) site at Bukit Kepong, Kuala Lumpur, Malaysia. RES2-D geophysical method was applied, capable of identification and quantification of the industrial wastes; buried hazardous materials (BHM) and their effects on the subsurface stratum, from the moderately saturated zones, to fully saturated zones housing the aquifer units underneath the water table. Six RES2-D survey profiles were respectively acquired along E-W, and N-S directions. The perpendicular arrangement of the RES2-D survey lines, was tenaciously designed to make possible, the industrial waste materials (IWM)and municipal solid waste (MSW) quantification, with sufficient length of survey lines set at 200 m, and electrode spacing of 5 m, to cover as much details segments of the IWM and MSW as possible. The six RES2-D inversion results, helped in the subsurface stratum classification into three layers, namely; soft layers, which encompasses the waste materials, with varied resistivity values i.e., 0-100 Ω-m, at 10-15 m depths. The consolidated layers produced varied resistivity values i.e., 101-400 Ω-m, at 15-20 m depths. The bedrock has the highest resistivity values i.e., 401-2000 Ω-m, at depths > 20 m. The estimated volume of the waste materials was 312,000 m 3, using 3-D Oasis Montaj modeling via rectangular prism model generated from the inverted RES2-D. Results from the geochemical analysis helped in the validation of the site as a potential contaminated zone with severe health effects.

8.
Data Brief ; 33: 106595, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33318980

RESUMO

Industrial, and municipal wastes are part of the main sources of environmental hazards as well as groundwater and surface water pollutions. If not well composed, treated, and safely disposed, it could permeate through the subsurface lithologies by reaching down to the underground water aquifers, particularly in zones of unprotected aquifer units. Pollutants, most especially the landfills leachates that encompassed organic contaminants, ammonia, nitrates, total nitrogen, suspended solids, heavy metals and soluble inorganic salts, i.e., soluble nitrogen, sulphur compound, sulphate and chlorides, could posed undesirable environmental impacts due to inappropriate disposals that may give rise to gaseous fumes and leachate formations. An electrical resistivity geophysical technique utilizing the RES2D no-invasive, cost-effective and rapid method of data collection was integrated with the 3D Oasis Montaj software to approximate the volume of the generated rectangular prism model of the contaminants delineated from mixtures of the industrial, and municipal wastes plumes to be 312,000 m 3.

9.
Data Brief ; 31: 105888, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32637495

RESUMO

This work contains dataset of measured activity concentrations of 40K, 238U, 232Th and gamma doses at 1 m above the ground level over Beryllium and Gold mining fields in Ifelodun and Moro respectively, Kwara State, North-central Nigeria. A well calibrated Super-Spec (RS-125) gamma spectrometer was used to carry out these measurements. Measurements were carried out manually in 72 randomly selected sample points. Statistical analyses of the data were explored to infer potential statistical relationships. The obtained dataset is presented for further assessment that can offer insights into the safety state of Ifelodu, Moro and their environs from radiation protection point of view. The data in this study could serve as a substantial baseline radiological data of the region for future monitoring and epidemiology researches.

10.
Heliyon ; 6(6): e04240, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32637683

RESUMO

Natural radioactivity measurement and dose assessment are important aspects of radiation protection. The goal of this study is to validate the previous results obtained from the in-situ measurements in the study area in order to ascertain the level of radiation hazards to the populaces living around the mining site.A3 × 3-inch lead-shielded NaI(Tl) detector was used to measure the activity concentrations of 40 K, 238 U and 232 Thin soil, water and guinea corn grain samples collected from a granite mining field in Asa, Kwara State, North-central Nigeria. The overall mean activity concentrations of 40 K, 238 U and 232 Th are 441.06, 11.51 and 15.42 Bqkg-1for the soil samples, 20.67, 0.66, and 0.88 BqL-1 for the water samples and 214.31, 5.25 and 8.86 Bqkg-,1respectively for the grain samples. The bioaccumulation/transfer factors are 0.49, 0.46 and 0.58 for 40 K, 238 U and 232 Th respectively. The mean values of all the radiological hazard parameters are within the permissible limit recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation. Consequently, the risk of indoor and outdoor gamma radiation exposure is comparatively less for these Granite soils. Hence, the results in this study will reference future studies in terms of basic radiological data.

11.
Data Brief ; 30: 105491, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32373680

RESUMO

The Transient Electro-Magnetic (TEM) geophysical technique was deployed to map and characterized the subsurface of Pahang River Basin along the East Coast Peninsula Malaysia. The data aimed at differentiating between the massive zones and the weak zones within the region, to also assess and differentiate the subsurface structures and comes up with recommendations for policy decision, formulation and plans on the flooding impact, surface water and groundwater managements, in addition to other environmental related issues ravaging the area. The data presented in this paper, showed the properties of the subsurface rocks underlain the region as beneficial to the Agriculturists; Climatologists; Engineers; Environmentalists; Geoscientists, Hydrologists and Policy formulation officers. The TEM data collection utilized a 100 m x 100 m single loop coil for both the Transmitter (Tx) loop and the Receiver (Rx) loop to produce a total surface area coverage of 10,000 m2 per survey line along a single profile. The total area covered in the data extended across an average area of 30 km x 40 km in parts of Maran, Temerloh and Jerantut districts, within the State of Pahang, East Coast, Peninsula Malaysia. The conductivity data recorded varied from -20 mS/m to about 440 mS/m at a maximum depth of about 375 m. On the other hand, the resistivity data recorded varied from 0 Oh-m to about 1000 Oh-m. The information derived from the data are intended for potential abstraction by the Malaysian Groundwater Management Board; the Department of Mineral and Geoscience; Department of Irrigation and Drainage; the Pahang State Water Board, and the Department of Agriculture.

12.
Data Brief ; 22: 830-835, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30766903

RESUMO

To identify the potential zones for gold mineralization at the Felda Chiku 3, Gua Musang, Kelantan, East coast Malaysia, twenty-one (21) geophysical survey lines were conducted at the proposed mineral exploration site using the pole - dipole of the electrical resistivity and induced polarization arrays to get the maximum depth of 150 m with 400 m survey length. From the resistivity and chargeability concentration maps, the potential mineralized zones as delineated, was observed to be dominantly concentrated towards the southwest and northern part of the area. The 3D resistivity and chargeability slice model present low resistivity values and high chargeability values that are well correlated which is palpable especially at the depths of 25 m and 50 m respectively. The data showed that the potential mineralized zones are trending approximately north-south directions. Forty (40) drilling locations were proposed for follow-up drilling based on the resistivity and chargeability models.

13.
MethodsX ; 6: 2504-2514, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31908980

RESUMO

In this study, a well calibrated Super-Spec (RS-125) gamma spectrometer was used to measure the activity concentrations of 40K, 238U, 232Th and gamma doses rate at 1 m above the ground level over a granite mining field in Asa, Kwara State, North-central Nigeria. Measurements were carried out in 50 randomly selected sample points. The overall mean activity concentrations of 40K, 238U, 232Th and gamma dose are 570.91, 42.86, 18.15 Bqkg-1 , and 60.11 nGyh-1 respectively. The results of the activity concentrations were used to estimate the corresponding radiation hazard parameters to assess the suitability of the granite for building and construction purposes. The data in this study could serve as the baseline radiological data of the region for future references. •Activity concentrations of 40K,238U,232Th and gamma doses were measured over a granite mining field in Asa.•The total mean activity concentrations of the radioisotopes and gamma dose are 570.91, 42.86, 18.15 Bqkg-1 , and 60.11 nGyh-1 respectively.•The radiological hazards are higher than the recommended permissible limits.

14.
Data Brief ; 21: 13-17, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30310834

RESUMO

Data on the micrometeorological parameters and Energy Fluxes at an intertidal zone of a Tropical Coastal Ocean was carried out on an installed eddy covariance instruments at a Muka head station in the north-western end of the Pinang Island (5°28'06''N, 100°12'01''E), Peninsula Malaysia. The vast source of the supply of energy and heat to the hydrologic and earth׳s energy cycles principally come from the oceans. The exchange of energies via air-sea interactions is crucial to the understanding of climate variability, energy, and water budget. The turbulent energy fluxes are primary mechanisms through which the ocean releases the heat absorbed from the solar radiations to the environment. The eddy covariance (EC) system is the direct technique of measuring the micrometeorological parameters which allow the measurement of these turbulent fluxes in the time scale of half-hourly basis at 20 Hz over a long period. The data being presented is the comparison of the two-year seasonality patterns of monsoons variability on the measured microclimate variables in the southern South China Sea coastal area.

15.
Data Brief ; 19: 1477-1481, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30229020

RESUMO

Air-sea flux exchanges influence the climate condition and the global carbon-moisture cycle. It is imperative to understand the fundamentals of the natural systems at the tropical coastal ocean and how the transformation takes place over the time. Hence, latent and sensible heat fluxes, microclimate variables, and surface water temperature data were collected using eddy covariance instruments mounted on a platform at a tropical coastal ocean station from November 2015 to October 2017. The research data is to gain the needful knowledge of the energy exchanges in the tropical climatic environment to further improve predictive algorithms or models. Therefore, it is intended that this data report will offer appropriate information for the Monsoonal, and diurnal patterns of latent (LE) and sensible (H) heats and hence, establish the relationship between microclimate variables on the energy fluxes at the peninsular Malaysian tropical coastal ocean.

16.
MethodsX ; 5: 448-453, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30090703

RESUMO

The southern South China coastal oceans within the South East Asian region are much lacking in the perception of the surface energy budget and evaporation over the ocean waters in response to climatic changes. The eddy covariance method was used to measure the energy fluxes, microclimate variables, and surface water temperature from November 2015 to October 2017 at the Straits of Malacca, South China Sea; Pulau Pinang, Malaysia, situated at latitude 5°28'06″N, and longitude 100°12'01″E. This work focused on the methodological approach to the air-sea energy fluxes data collection and analysis. In this regard, the method applied for the direct measurements and analysis of energy fluxes and other meteorological parameters in the site is considered and reported. •The paper summarizes the analysis of energy fluxes, microclimate variables, and surface water temperature data in a tropical coastal ocean station using the eddy covariance method.•The methodological approach illustrates the method of analysis applied in this study which can be compared and used for similar studies in other places.•The reproducible data analysis technique matches similar comparative methods such as Matlab and Python.

17.
Data Brief ; 18: 1864-1868, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29904689

RESUMO

The paper presents the data from the surface and subsurface mapping of this area for the purpose of siting industrial city in the area. The field data collected combine with the borehole data was to successfully apply these to solving geological, environmental and engineering complications posed by the complexity of the subsurface geological structures underlain this area. The Electrical Resistivity, (ER) and Induced Polarization, (IP) data were initially processed using RES2DINV software model to generate the depth to the lithological units together with topographic correction. The 2-D ER and IP data were collected from 23rd April 2017 up until 7th May 2017 covering a total of about 17.6 km along 44 survey lines using ABEM Terrameter SAS4000 for the field measurement. A total of 20 Borehole logs data were recorded to better characterized in-situ, the subsurface geological formations emplaced in the study area. The study area is located at Bagan Datuk, Perak Darul Ridzuan situated on Latitude 2° 44.653'N and Longitudes 104° 28.79' E along the west coast Peninsula Malaysia. The topography of the area is generally flat low-laying and elevation range from about 0 m to 32 m above mean sea level (MSL).

18.
Data Brief ; 19: 798-803, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29900375

RESUMO

A secondary dataset was generated from the Euldph-λ semi-automatic Algorithm, (ESA) developed to automatically computes various depths to the magnetic anomalies using a primary data set from gridded aeromagnetic data obtained in the study area. Euler Deconvolution techniques, (EDT), was adopted in the identification and definition of the magnetic anomaly source rocks in the study area. The aim is to use the straightforward technique to pinpoint magnetic anomalies at a depth which substantiate mineralization potential of the area. The ESA was integrated with the imaging function of Oasis Montaj 2014 source parameter from Geosoft® Inc. From the data, it could be summarized that similar tectonic processes during the deformation and metamorphic activities, the subsurface structures of the study area produce corresponding trending form.

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