Research Interests:
Research Interests:
In coastal regions of Bangladesh, sources of irrigation are rain, surface and groundwater. Due to rainfall anomaly and saline contamination, it is important to identify deep groundwater that is eligible for irrigation. The main goal of... more
In coastal regions of Bangladesh, sources of irrigation are rain, surface and groundwater. Due to rainfall anomaly and saline contamination, it is important to identify deep groundwater that is eligible for irrigation. The main goal of the study was to identify deep groundwater which is suitable for irrigation. Satkhira Sadar Upazila, at the southwestern coastal zone of Bangladesh, was the study area, which was divided into North, Center and South zones. Twenty samples of groundwater were analyzed for salinity (0.65- ...
Research Interests:
Research Interests: Geology and Geosciences
Low and Intermediate level wastes (LILW) in Bangladesh are being generated from operation, repair and maintenance of 3MW TRIGA MARK-II research reactor (RR), 14 MeV Neutron Generator and research & commercial irradiators such as Co-60 and... more
Low and Intermediate level wastes (LILW) in Bangladesh are being generated from operation, repair and maintenance of 3MW TRIGA MARK-II research reactor (RR), 14 MeV Neutron Generator and research & commercial irradiators such as Co-60 and isotope production for medical purposes. The wastes arising from these sources are generally spent ion exchange resins, graphite, lead and polythene plugs, contaminated vials, hand gloves, plastic syringes, tissue papers, shoe-covers, protective cloths, plastic and metallic wares, spent and disused sources (SRS), activated carbon, gaseous discharges, etc. The radionuclides involved with these wastes areCo-60, Cs134 & 137, Sr-90, Ir-192, Tc-99m, I-131, I-125, C-14, H-3, Ra-226, Am-Be neutron sources, Cm-244, Am-241, Cr-51, Mn-54, Zn-65, P-32, Sc-46, etc. Solid radioactive wastes are collected, segregated at the place of generation and stored in interim-storage rooms of the Central Radioactive Waste Processing and Storage Facility (CWPSF), developed ...
Research Interests:
The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first of its kind in Bangladesh. The range of radon concentration was measured as 8–4360 Bq/m3 with... more
The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first of its kind in Bangladesh. The range of radon concentration was measured as 8–4360 Bq/m3 with an average of 851.41 Bq/m3. Among the measured values, 2120–4360 Bq/m3 was observed in the Tertiary sediments whereas 8–584 Bq/m3 was found in the Recent alluvial soil of different bils and haors. These high radon concentrations are explained by geogenic factors such as mineral content in rocks, alluvium cover, sufficient porosity, probable subsurface fault, and flooding by water streamed through adjacent uranium-rich areas in India. The radon values indicate that the rock formations are promising for uranium mineralization. The radon concentration in rocks and soils are well comparable to the similar studies of the other parts of the world. The results are in good agreement with the previous radiometric survey results, suggestive to extensive exploration activities to confirm uranium mineralization in the area. Moreover, the average annual effective dose of 0.008092 mSv/y in the region calculated from the radon values is within the WHO and ICRP safety limits.
Research Interests:
Vertical electrical sounding has been carried out in a coastal area in the southern part of Bangladesh to locate the groundwater aquifers containing fresh water. The Interpex1X1Dv3 computer program was used to process the field apparent... more
Vertical electrical sounding has been carried out in a coastal area in the southern part of Bangladesh to locate the groundwater aquifers containing fresh water. The Interpex1X1Dv3 computer program was used to process the field apparent resistivity data sets obtained from the vertical electrical sounding. Geoelectric layers were identified in the context of resistivity and thickness from the vertical electrical sounding data. From the initial parameters layered model was achieved using the inversion technique. Correlation of the obtained layer model with a nearby lithologic log concludes the groundwater aquifer system of the area. From the electrical properties of the subsurface layers, water bearing layers were detected and characterized. Very fine sand geoelectric layer with a thickness varying from 20 to 143 meters is an upper aquifer and has 0.66–14.02 Ωm apparent resistivity value. Fine sand geoelectric layer with 0.21-5.99 Ωm apparent resistivity value is lower aquifer with m...
Research Interests:
To understand the groundwater flow systems of Bengal Delta, Bangladesh, shallow, intermediate and deep groundwater; major river water and monthly weighted rainfall samples were collected from the study area for major ions and... more
To understand the groundwater flow systems of Bengal Delta, Bangladesh, shallow, intermediate and deep groundwater; major river water and monthly weighted rainfall samples were collected from the study area for major ions and environmental isotope analyses. The shallow and intermediate depth groundwaters are dominantly Ca-Mg-HCO 3 and/or Na-Ca-Mg-HCO 3 types, and the deep groundwaters are mainly of Na-Cl-HCO 3 , Na-Cl and Na-Ca-Mg-Cl types. In deep groundwater, the loss of Ca 2+ are ion exchanged for Na + along the flow paths, which are initially enriched in Ca 2+. A plot of δ 18 O versus δ 2 H of monthly weighted rainfall data collected in Savar area is considered as the Local Meteoric Water Line (δD = 7.7δ 18 O + 10.7) for the study area. Most of the groundwater falls on the meteoric water line, indicating an origin from monsoon rain and floodwater with some evaporation effects for shallow groundwater. The shallow groundwater tritium content varies from 0 to 4.6 TU that are within...
Research Interests: Geology and Geosciences
The shallow aquifers (depths <70m) in Meghna basin in eastern Bangladesh contain unacceptably high arsenic concentration (> permissible limit 50 g/L). A comprehensive isotope geochemical study was conducted in four high-arsenic... more
The shallow aquifers (depths <70m) in Meghna basin in eastern Bangladesh contain unacceptably high arsenic concentration (> permissible limit 50 g/L). A comprehensive isotope geochemical study was conducted in four high-arsenic upazilas - Laksham, Chandpur Sadar, Kachua and Lakshmipur to understand the potential of deep aquifer. Two major hydrochemical problems were identified in the deep aquifer, specifically high salinity and unacceptable concentrations of trace elements like iron and manganese. The range of arsenic concentration in all shallow wells is 244–733 g/L. Except for two deep wells in Kachua, which are at intermediate depths ranging from 128 to 137m, contain high arsenic concentrations (range 115–200 g/L). These two samples have heavier stable isotope compositions of oxygen-18 (–2.23 & –3.11 ‰) and deuterium (–16.3 & –17.6 ‰) compared with water samples from similar depths. The compositions also appear to have been affected by evaporation. The isotopic compositi...
Low and Intermediate level wastes (LILW) in Bangladesh are being generated from operation, repair and maintenance of 3MW TRIGA MARK-II research reactor (RR), 14 MeV Neutron Generator and research & commercial irradiators such as Co-60 and... more
Low and Intermediate level wastes (LILW) in Bangladesh are being generated from operation, repair and maintenance of 3MW TRIGA MARK-II research reactor (RR), 14 MeV Neutron Generator and research & commercial irradiators such as Co-60 and isotope production for medical purposes. The wastes arising from these sources are generally spent ion exchange resins, graphite, lead and polythene plugs, contaminated vials, hand gloves, plastic syringes, tissue papers, shoe-covers, protective cloths, plastic and metallic wares, spent and disused sources (SRS), activated carbon, gaseous discharges, etc. The radionuclides involved with these wastes areCo-60, Cs134 & 137, Sr-90, Ir-192, Tc-99m, I-131, I-125, C-14, H-3, Ra-226, Am-Be neutron sources, Cm-244, Am-241, Cr-51, Mn-54, Zn-65, P-32, Sc-46, etc. Solid radioactive wastes are collected, segregated at the place of generation and stored in interim-storage rooms of the Central Radioactive Waste Processing and Storage Facility (CWPSF), developed ...
Research Interests:
A total number of twenty topsoil samples were analyzed for heavy metals using X-ray Fluorescence System where as radioactivity levels of seven samples were determined by High Purity Germanium (HPGe) detector. The average concentrations of... more
A total number of twenty topsoil samples were analyzed for heavy metals using X-ray Fluorescence System where as radioactivity levels of seven samples were determined by High Purity Germanium (HPGe) detector. The average concentrations of Mn, Zn, Cr, Co and Cu were 584.68, 213.04, 190.33, 164.63 and 100.18 mg/kg respectively in topsoil, which were much above the recommended level as well as higher than their corresponding background values thus indicating environmental pollution. The order of average heavy metal contents was Mn>Zn>Cr>Co>Cu>As>Pb in topsoil. Soil pollution assessment was carried out by using enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (CF), degree of contamination (Cd) and pollution load index (PLI). The soil shows moderate enrichment of Cu and minimal enrichment with Zn, Pb, Cr, As, and Co. Whereas Igeo and CF exhibit moderate to high contamination for Mn, Zn, Cu, Cr and Co. The results of PLI of analyzed heavy metals...
Research Interests:
The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first of its kind in Bangladesh. The range of radon concentration was measured as 8–4360 Bq/m3 with... more
The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first of its kind in Bangladesh. The range of radon concentration was measured as 8–4360 Bq/m3 with an average of 851.41 Bq/m3. Among the measured values, 2120–4360 Bq/m3 was observed in the Tertiary sediments whereas 8–584 Bq/m3 was found in the Recent alluvial soil of different bils and haors. These high radon concentrations are explained by geogenic factors such as mineral content in rocks, alluvium cover, sufficient porosity, probable subsurface fault, and flooding by water streamed through adjacent uranium-rich areas in India. The radon values indicate that the rock formations are promising for uranium mineralization. The radon concentration in rocks and soils are well comparable to the similar studies of the other parts of the world. The results are in good agreement with the previous radiometric survey results, suggestive to extensive exploration activities to confirm uranium mineralization in the area. Moreover, the average annual effective dose of 0.008092 mSv/y in the region calculated from the radon values is within the WHO and ICRP safety limits.
Research Interests:
Heavy metals (Pb, As, Zn, Cu, Ni, Co and Cd) concentrations are determined from the Buriganga riverbed sediments to evaluate their levels and the distribution by using X-ray fluorescence spectroscopy (XRF). The average concentrations of... more
Heavy metals (Pb, As, Zn, Cu, Ni, Co and Cd) concentrations are determined from the Buriganga riverbed sediments to evaluate their levels and the distribution by using X-ray fluorescence spectroscopy (XRF). The average concentrations of heavy metals Pb, As, Zn, Cu, Ni, Co and Cd are 4.00, 34.90, 50.70, 49.80, 64.50, 8.90 and 1.17 mg/kg, respectively in river sediments. The average concentration of As, Cu, Ni, Co and Cd exceeds the threshold effect level of Canadian sediment quality guideline in relation to river sediment. Hence, the high concentration of these heavy metals in river sediments may cause serious threat to the aquatic environment and the public health of adjacent people. The order of heavy metal abundances is Ni > Zn > Cu > As > Co> Pb > Cd in present study. Multivariate statistical analyses such as principal component analysis, cluster analysis and correlation matrix shows significant anthropogenic and geogenic intrusions of Pb, As, Zn, Cu, Ni, Co and...
Research Interests:
The radioactivity levels of naturally occurring radionuclides 226 Ra, 232 Th and 40 K in thirteen topsoil samples, collected from Savar industrial area of Bangladesh, were measured by gamma ray spectrometry system using a High Purity... more
The radioactivity levels of naturally occurring radionuclides 226 Ra, 232 Th and 40 K in thirteen topsoil samples, collected from Savar industrial area of Bangladesh, were measured by gamma ray spectrometry system using a High Purity Germanium (HPGe) detector of 40% relative efficiency. The calculated average activity concentrations of 226 Ra, 232 Th and 40 K in the collected samples were 23.31 Bq.kg-1 , 42.24 Bq.kg-1 and 733.19 Bq.kg-1 , respectively. The average activity concentration of 232 Th and 226 Ra in the present study is lower than that of the worldwide average value but the concentration for 40 K is much higher than the world average of 420 Bq.kg-1. The estimated average absorbed dose rate (D), the outdoor annual effective dose (E) and the external hazard index (H ex) were found as 67.08 nGyh-1 , 0.08 mSvy-1 and 0.38 Bq.Kg-1 , respectively. The absorbed dose rate and outdoor annual effective dose are slightly higher than the world average value but the external hazard ind...
Research Interests:
Vertical electrical sounding has been carried out in a coastal area in the southern part of Bangladesh to locate the groundwater aquifers containing fresh water. The Interpex1X1Dv3 computer program was used to process the field apparent... more
Vertical electrical sounding has been carried out in a coastal area in the southern part of Bangladesh to locate the groundwater aquifers containing fresh water. The Interpex1X1Dv3 computer program was used to process the field apparent resistivity data sets obtained from the vertical electrical sounding. Geoelectric layers were identified in the context of resistivity and thickness from the vertical electrical sounding data. From the initial parameters layered model was achieved using the inversion technique. Correlation of the obtained layer model with a nearby lithologic log concludes the groundwater aquifer system of the area. From the electrical properties of the subsurface layers, water bearing layers were detected and characterized. Very fine sand geoelectric layer with a thickness varying from 20 to 143 meters is an upper aquifer and has 0.66–14.02 Ωm apparent resistivity value. Fine sand geoelectric layer with 0.21-5.99 Ωm apparent resistivity value is lower aquifer with m...
Research Interests:
A total number of twenty water samples of which seven groundwater, six river water and seven effluent samples were collected from Savar industrial area in Bangladesh for heavy metals analysis using ICP-MS system. The average concentration... more
A total number of twenty water samples of which seven groundwater, six river water and seven effluent samples were collected from Savar industrial area in Bangladesh for heavy metals analysis using ICP-MS system. The average concentration of Fe, Mn, Cr, Zn, As, Ni and Pb were 929.97, 101.01, 6.08, 33.36, 9.18, 2.03 and 3.99 mg/L in groundwater; 286.48, 37.65, 0.13, 9.18, 1.39, 1.53 and 1.26 mg/L in river water and 606.64, 72.71, 5.04, 25.05, 1.72, 2.37 and 1.56 mg/L in effluent, respectively. The average concentration of Cr, Mn, Ni, Fe, Pb, Zn and As exceed WHO and DoE, Bangladesh limits in relation to river water and groundwater. The order of average heavy metal content was Fe>Mn>Zn>Cr>Ni>As>Pb in effluent water, Fe>Mn>Zn>Cr>Pb>Ni>As in groundwater and Fe>Mn>Zn>Ni>As>Pb>Cr in river water. Multivariate statistical analyses such as principal component, cluster analysis and correlation matrix shows significant anthropogenic and geo...
Research Interests:
A total number of twenty topsoil samples were analyzed for heavy metals using X-ray Fluorescence System where as radioactivity levels of seven samples were determined by High Purity Germanium (HPGe) detector. The average concentrations of... more
A total number of twenty topsoil samples were analyzed for heavy metals using X-ray Fluorescence System where as radioactivity levels of seven samples were determined by High Purity Germanium (HPGe) detector. The average concentrations of Mn, Zn, Cr, Co and Cu were 584.68, 213.04, 190.33, 164.63 and 100.18 mg/kg respectively in topsoil, which were much above the recommended level as well as higher than their corresponding background values thus indicating environmental pollution. The order of average heavy metal contents was Mn>Zn>Cr>Co>Cu>As>Pb in topsoil. Soil pollution assessment was carried out by using enrichment factor (EF), geoaccumulation index (Igeo), contamination factor (CF), degree of contamination (Cd) and pollution load index (PLI). The soil shows moderate enrichment of Cu and minimal enrichment with Zn, Pb, Cr, As, and Co. Whereas Igeo and CF exhibit moderate to high contamination for Mn, Zn, Cu, Cr and Co. The results of PLI of analyzed heavy metals...
Research Interests:
The radioactivity levels of naturally occurring radionuclides 226 Ra, 232 Th and 40 K in thirteen topsoil samples, collected from Savar industrial area of Bangladesh, were measured by gamma ray spectrometry system using a High Purity... more
The radioactivity levels of naturally occurring radionuclides 226 Ra, 232 Th and 40 K in thirteen topsoil samples, collected from Savar industrial area of Bangladesh, were measured by gamma ray spectrometry system using a High Purity Germanium (HPGe) detector of 40% relative efficiency. The calculated average activity concentrations of 226 Ra, 232 Th and 40 K in the collected samples were 23.31 Bq.kg-1 , 42.24 Bq.kg-1 and 733.19 Bq.kg-1 , respectively. The average activity concentration of 232 Th and 226 Ra in the present study is lower than that of the worldwide average value but the concentration for 40 K is much higher than the world average of 420 Bq.kg-1. The estimated average absorbed dose rate (D), the outdoor annual effective dose (E) and the external hazard index (H ex) were found as 67.08 nGyh-1 , 0.08 mSvy-1 and 0.38 Bq.Kg-1 , respectively. The absorbed dose rate and outdoor annual effective dose are slightly higher than the world average value but the external hazard ind...
Research Interests:
Research Interests:
A total number of twenty water samples of which seven groundwater, six river water and seven effluent samples were collected from Savar industrial area in Bangladesh for heavy metals analysis using ICP-MS system. The average concentration... more
A total number of twenty water samples of which seven groundwater, six river water and seven effluent samples were collected from Savar industrial area in Bangladesh for heavy metals analysis using ICP-MS system. The average concentration of Fe, Mn, Cr, Zn, As, Ni and Pb were 929.97, 101.01, 6.08, 33.36, 9.18, 2.03 and 3.99 mg/L in groundwater; 286.48, 37.65, 0.13, 9.18, 1.39, 1.53 and 1.26 mg/L in river water and 606.64, 72.71, 5.04, 25.05, 1.72, 2.37 and 1.56 mg/L in effluent, respectively. The average concentration of Cr, Mn, Ni, Fe, Pb, Zn and As exceed WHO and DoE, Bangladesh limits in relation to river water and groundwater. The order of average heavy metal content was Fe>Mn>Zn>Cr>Ni>As>Pb in effluent water, Fe>Mn>Zn>Cr>Pb>Ni>As in groundwater and Fe>Mn>Zn>Ni>As>Pb>Cr in river water. Multivariate statistical analyses such as principal component, cluster analysis and correlation matrix shows significant anthropogenic and geo...
Research Interests:
... groundwater flow systems within the Bengal delta aquifers discharging along the coastal region. ... In these aquifers, as the thickness of the confining clay layers increase with depth ... Finally, deep groundwater discharges into the... more
... groundwater flow systems within the Bengal delta aquifers discharging along the coastal region. ... In these aquifers, as the thickness of the confining clay layers increase with depth ... Finally, deep groundwater discharges into the Bay of Bengal as submarine groundwater discharge ...
Research Interests:
Twenty three groundwater samples, three riverwater samples and a tannery effluent were collected from Hazaribagh area in Bangladesh; in order to evaluate their geochemical composition and quality. The physicochemical parameters pH, EC,... more
Twenty three groundwater samples, three riverwater samples and a tannery effluent were collected from Hazaribagh area in Bangladesh; in order to evaluate their geochemical composition and quality. The physicochemical parameters pH, EC, DO, hardness, HCO3 –, Cl–, SO4 2+, NO3 –, P, Na+, K+, Ca2+, Mg2+, Fe, Mn, Cu, Zn, Pb, Cd and Cr were measured in these samples. Groundwater was dominantly of Ca-Mg-HCO3 type with Ca2+ and HCO3 – being the dominant cation and anion, respectively. Na+ -normalized Ca2+ versus HCO3 – and Na+ -normalized Ca2+ versus Mg2+ plots showed that the groundwater samples were influenced by carbonate dissolution. Average concentration of Fe, Pb and Cd exceeded World Health Organization (WHO) limits in relation to groundwater and riverwater. DO saturation in river water was 200 times lower than the standard limit, making it unable to sustain aquatic life. Principal Component Analysis (PCA) extracted five PCs using the correlation matrix to reflect the processes influ...
Twenty three groundwater samples, three riverwater samples and a tannery effluent were collected from Hazaribagh area in Bangladesh; in order to evaluate their geochemical composition and quality. The physicochemical parameters pH, EC,... more
Twenty three groundwater samples, three riverwater samples and a tannery effluent were collected from Hazaribagh area in Bangladesh; in order to evaluate their geochemical composition and quality. The physicochemical parameters pH, EC, DO, hardness, HCO3 –, Cl–, SO4 2+, NO3 –, P, Na+, K+, Ca2+, Mg2+, Fe, Mn, Cu, Zn, Pb, Cd and Cr were measured in these samples. Groundwater was dominantly of Ca-Mg-HCO3 type with Ca2+ and HCO3 – being the dominant cation and anion, respectively. Na+ -normalized Ca2+ versus HCO3 – and Na+ -normalized Ca2+ versus Mg2+ plots showed that the groundwater samples were influenced by carbonate dissolution. Average concentration of Fe, Pb and Cd exceeded World Health Organization (WHO) limits in relation to groundwater and riverwater. DO saturation in river water was 200 times lower than the standard limit, making it unable to sustain aquatic life. Principal Component Analysis (PCA) extracted five PCs using the correlation matrix to reflect the processes influ...
ABSTRACT The geochemical compositions of topsoil and subsoil samples collected from proposed Rooppur nuclear power plant site were analyzed in order to generate baseline data for assessing future contamination. The examined soils are... more
ABSTRACT The geochemical compositions of topsoil and subsoil samples collected from proposed Rooppur nuclear power plant site were analyzed in order to generate baseline data for assessing future contamination. The examined soils are mainly silty clay type; and quartz, K-feldspar, albite, muscovite, vermiculite and calcite are major minerals constituting the soil compositions. Silicon is the dominant element in all assorted samples followed by Al, Fe, K, Ca, Na, Mg and Ti. On contrary, the order of trace element abundances in the soils is Mn&gt;S&gt;Zr&gt;Zn&gt;Cr&gt;Sr&gt;Rb&gt;V&gt;Ce&gt;Pb&gt;Y&gt;As&gt;Cu&gt;Co&gt;Th. The calculated enrichment factors, geoaccumulation index and contamination factors suggest that the soils are none to very lightly polluted with respect to most metals and only sample #9 is moderately to highly polluted by As, Pb, S and Zn. The calculated pollution load index (PLI) varied between 0.98 and 1.24 with a mean of 1.08. Correlation, hierarchical cluster and principal component analyses suggest that the enrichment of As, Pb, S and Z are probably caused by human activities, mainly due to agricultural production, which has directly affected the chemical compositions of topsoils. The very low correlation of total organic carbon with As, Co, Cr, Cu, Pb and Cu, and negative relationship with Rb, S, Sr, Th, Y, Zn and Zr indicates organic carbon is irrelevant to the accumulation of these elements in soils.
Kenneth G. Stollenwerk ⁎, George N. Breit, Alan H. Welch, James C. Yount, John W. Whitney, Andrea L. Foster, M. Nehal Uddin, Ratan K. Majumder, Nasir Ahmed US Geological Survey, MS 413, Box 25046, Federal Center, Denver, CO 80225, USA US... more
Kenneth G. Stollenwerk ⁎, George N. Breit, Alan H. Welch, James C. Yount, John W. Whitney, Andrea L. Foster, M. Nehal Uddin, Ratan K. Majumder, Nasir Ahmed US Geological Survey, MS 413, Box 25046, Federal Center, Denver, CO 80225, USA US Geological Survey, MS 973, Box 25046, Federal Center, Denver, CO 80225, USA US Geological Survey, 2730 N. Deer Run Road, Carson City, NV 89701, USA US Geological Survey, MS 980, Box 25046, Federal Center, Denver, CO 80225, USA US Geological Survey, 345 Middlefield Rd., MS 901, Menlo Park, CA 94025, USA Geological Survey Bangladesh, Dhaka, Bangladesh Bangladesh Atomic Energy Commission, Dhaka, Bangladesh
Research Interests:
ABSTRACT Cathodic reduction of nitrate ions has been carried out using a sandwich type membrane reactor having a configuration of Pt|Nafion|Pt–Cu in absence of any supporting electrolyte. Both Pt and Cu metals are in polycrystalline form... more
ABSTRACT Cathodic reduction of nitrate ions has been carried out using a sandwich type membrane reactor having a configuration of Pt|Nafion|Pt–Cu in absence of any supporting electrolyte. Both Pt and Cu metals are in polycrystalline form on the cathodic surface immobilized on Nafion membrane. The globular Cu particles have a wide range of sizes (70–120 nm). During the course of electrolysis in the reactor, the bimetallic Pt–Cu surface reduces NO3–into NH3 and N2 by means of electrochemical and catalytic hydrogenation reactions, respectively. The electrochemical contribution of nitrate reduction has been investigated in details by using voltammetric and electrolysis techniques. The NO3–ions are electrochemically reduced using a consecutive reaction. On the consecutive way of reduction, the intermediate NO2–and final product NH3 are generated at–0.74 V and–1.1 V versus Ag/AgCl (std. KCl), respectively. The molecular N2 is generated by means of catalytic reactions followed by electrochemical hydrogen evolution.
Research Interests:
Probable sources and mechanisms of arsenic (As) release in shallow aquifer in eastern Bangladesh are evaluated using statistical analysis of groundwater compositions. Dissolved As in 39 samples ranged from 8.05 to 341.5 microg/L with an... more
Probable sources and mechanisms of arsenic (As) release in shallow aquifer in eastern Bangladesh are evaluated using statistical analysis of groundwater compositions. Dissolved As in 39 samples ranged from 8.05 to 341.5 microg/L with an average of 95.14 microg/L. Ninety seven percent of wells exceed the WHO limit (10 microg/L) for safe drinking water. Principal component analysis is applied to reduce 16 measured compositional variables to five significant components (principal components--PCs) that explain 86.63% of the geochemical variance. Two component loadings, namely PC 1 and PC 2 (45.31% and 23.05%) indicate the natural processes within the aquifers in which organic matter is a key reactant in the weathering reactions. Four groups of wells are defined by the PCA and each group of wells represents distinct physicochemical characteristics. Among them, group III groundwater shows higher As concentration together with high concentrations of Fe, Mn, dissolved organic carbon, PO4(3-) and HCO3(-) than groups I and II. Speciation calculations suggest that only wells of group III are saturated with respect to siderite, and all groups of samples are supersaturated with respect of rhodochrosite. The relationship of As with these parameters in the different groups of wells of the study area suggests that reductive dissolution of Fe-Mn oxyhydroxides with microbially mediated degradation of organic matter is considered to be the dominant processes to release As in groundwater.
Research Interests: Geography, Chemistry, Carbon, Arsenic, Groundwater, and 15 moreEnvironmental Monitoring, Bangladesh, Medicine, Multidisciplinary, Manganese, Ground Water, Drinking Water, Iron, Dissolution, Aquifers, Environmental monitoring and assessment, AQUIFER, Dissolved Organic Carbon, Organic Matter, and Environmental
Research Interests: Civil Engineering, Chemistry, Environmental Geology, Principal Component Analysis, Arsenic, and 10 moreGroundwater, Groundwater Contamination, Environmental Chemistry, Earth and Environmental Sciences, Drinking Water, Dissolution, AQUIFER, Interdisciplinary Engineering, Organic Matter, and Environmental
Research Interests:
Research Interests:
ABSTRACT Geochemical characteristics of shallow groundwaters and core sediments are studied to better understand the sources and transportation process responsible for As and Mn enrichment in Singair Upazila of Manikgonj District in... more
ABSTRACT Geochemical characteristics of shallow groundwaters and core sediments are studied to better understand the sources and transportation process responsible for As and Mn enrichment in Singair Upazila of Manikgonj District in Bangladesh. Results demonstrate that the groundwater is mostly of Ca-HCO3 and Ca-Mg-HCO3 types. Concentrations of As in groundwater ranged from 1 to 159 μg/L, with about 59% of these exceeded the WHO drinking water guideline of 10 mg/L. In addition, all groundwater samples had higher concentrations of Mn (0.6–5.7 mg/L) and Fe (0.9–16.5 mg/L) than the WHO drinking water guidelines (0.4 and 0.3 μg/L, respectively). Most groundwaters contained both As(III) and As(V) species in which the concentration of As(III) was generally higher than that of As(V). High concentration of As (23 mg/kg) with elevated levels of FeO, MnO and TOC were found within the upper 15 m of silty clay sediments. Multivariate geostatistical analysis showed that dissolution of the Fe–Mn oxides was the dominant process of As and Mn release in groundwater. Geochemical modeling suggested that the concentrations of As, Mn, Fe and \({{\rm PO}_{4}^{3-}}\) in groundwaters were also influenced by secondary minerals phases in addition to redox processes.
Research Interests:
Borehole temperatures were measured in observation wells to determine the temperature-depth profile, magnitude of temperature and thermal gradient. The observed temperature profiles are classified into recharge and discharge types. The... more
Borehole temperatures were measured in observation wells to determine the temperature-depth profile, magnitude of temperature and thermal gradient. The observed temperature profiles are classified into recharge and discharge types. The recharge-type wells are located in the northern site of the study area. Meanwhile, discharge-type wells are found in the southern site of the study area. The 2-D cross-section of subsurface temperature shows that the shallow groundwater temperature in the southern discharge area is higher than that of the northern recharge area. The calculated temperature-depth profiles for shallow wells show the recharge rate ranging from 0.04 to 1.35 m/year and discharge rate within the range of -0.2 to -0.79 m/year. On the contrary, the recharge rate is 0.05 to 0.16 m/year and discharge rate -0.15 m/year for the deep well sites. The present study has revealed the existence of shallow and deep groundwater flow systems in Bengal Delta aquifers.
Research Interests:
Research Interests: Environmental Science, Geology, Radiation, Construction Materials, Risk assessment, and 15 moreIran, Radiation Measurements, Dose rate, Radiometry, Public health systems and services research, Building Material, Background Radiation, Risk Assessment, Indexation, Natural Radioactivity, Materials Testing, Radioisotopes, Radium, Effective Dose, and Organization for Economic Cooperation and Development
Research Interests:
Research Interests:
Research Interests: Geology, Bangladesh, River, Geosciences, Heavy Minerals, and 3 moreSAND, Brahmaputra River, and Jamuna River
Groundwater of Chapai Nawabganj town has been studied using hydrogeological, hydrochemical and environmental isotope (?18O, ?2H, ?13C, 3H and 14C) data. Aquifer underneath the study area is divided into unconfined to semi-confined... more
Groundwater of Chapai Nawabganj town has been studied using hydrogeological, hydrochemical and environmental isotope (?18O, ?2H, ?13C, 3H and 14C) data. Aquifer underneath the study area is divided into unconfined to semi-confined Holocene alluvial floodplain aquifer and confined Plio-Pleistocene Dupi Tila sandstone aquifer. Chemical composition of groundwater is characterized by high concentrations of Mg2+, Na+, Ca2+, HCO3-, FeTotal, and low concentrations of Mn2+, NO3 - and PO4 3-. Groundwater samples are mainly Mg-Ca-HCO3 and Na-Mg-Ca-HCO3 types and Na-Mg-Ca-Cl-HCO3 type of water is also found at some places. Based on Cl- and SO42- concentrations groundwater is normal chloride and normal sulphate water, respectively. In terms of SAR and EC values water is excellent for irrigation purpose. The isotopic composition also suggests some segregation of groundwater from the different aquifers and indicates different ages of recharge. DOI: http://dx.doi.org/10.3329/jbas.v38i2.21338 Journ...
Research Interests:
Research Interests:
The cement industry is considered as one of the basic industries that plays an important role in the national economy of developing countries. Activity concentrations of (226)Ra, (232)Th and (40)K in Assiut cement and other local cement... more
The cement industry is considered as one of the basic industries that plays an important role in the national economy of developing countries. Activity concentrations of (226)Ra, (232)Th and (40)K in Assiut cement and other local cement types from different Egyptian factories has been measured by using gamma-ray spectrometry. From the measured gamma-ray spectra, specific activities were determined. The measured activity concentrations for these natural radionuclides were compared with the reported data for other countries. The average values obtained for (226)Ra, (232)Th and (40)K activity concentration in different types of cement are lower than the corresponding global values reported in UNSCEAR publications. The obtained results show that the averages of radiation hazard parameters for Assiut cement factory are lower than the acceptable level of 370Bqkg(-1) for radium equivalent Ra(eq), 1 for level index Igammar, the external hazard index Hex &amp;lt;/=1 and 59 (nGyh(-1)) for absorbe...
Research Interests:
Research Interests:
Recognition of arsenic (As) contamination of shallow fluvio-deltaic aquifers in the Bengal Basin has resulted in increasing exploitation of groundwater from deeper aquifers that generally contain low concentrations of dissolved As.... more
Recognition of arsenic (As) contamination of shallow fluvio-deltaic aquifers in the Bengal Basin has resulted in increasing exploitation of groundwater from deeper aquifers that generally contain low concentrations of dissolved As. Pumping-induced infiltration of high-As groundwater ...
Research Interests:
Research Interests:
Groundwater and river water samples were collected from the study area to investigate the spatial distribution of nitrate (NO 3 − ) in the central-west region of Bangladesh. The shallow and deep groundwater nitrate concentrations ranged... more
Groundwater and river water samples were collected from the study area to investigate the spatial distribution of nitrate (NO 3 − ) in the central-west region of Bangladesh. The shallow and deep groundwater nitrate concentrations ranged from <0.10 to 75.12 and <0.10 to 40.78 mg/L, ...
Research Interests:
In this study, the hydrochemical characteristics of shallow groundwater in a coastal region (Khulna) of southwest Bangladesh have been evaluated based on different indices for drinking and irrigation uses. Water samples were collected... more
In this study, the hydrochemical characteristics of shallow groundwater in a coastal region (Khulna) of southwest Bangladesh have been evaluated based on different indices for drinking and irrigation uses. Water samples were collected from 26 boreholes and analyzed for major cations and anions. Other physico-chemical parameters like pH, electrical conductivity (EC), and total dissolved solids were also measured. Most groundwater is slightly alkaline and largely varies in chemical composition, e.g. EC ranges from 962 to 9,370 μs/cm. The abundance of the major ions is as follows: Na+ > Ca2+ > Mg2+ > K+ = Cl− > HCO3− > SO42− > NO3−. Interpretation of analytical data shows two major hydrochemical facies (Na+–K+–Cl−–SO42− and Na+–K+–HCO3−) in the study area. Salinity, total hardness, and sodium percentage (Na%) indicate that most of the groundwater samples are not suitable for irrigation as well as for domestic purposes and far from drinking water standard. Results sugg...
Research Interests:
Research Interests:
Twenty groundwater samples were collected from two different areas in Satkhira Sadar Upazila to identify the source of salinity in deep groundwater aquifer. Most of the analyzed groundwater is of Na–Cl–HCO 3 type water. The trends of... more
Twenty groundwater samples were collected from two different areas in Satkhira Sadar Upazila to identify the source of salinity in deep groundwater aquifer. Most of the analyzed groundwater is of Na–Cl–HCO 3 type water. The trends of anion and cation are Cl−> HCO 3−> NO 3−> SO 4 2− and Na+> Ca 2+> Mg 2+> K+, respectively. Groundwater chemistry in the study area is mainly governed by rock dissolution and ion exchange. The dissolved minerals in groundwater mainly come from silicate weathering. The salinity of ...