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Evaluating the geochemistry of Bam salt dome in Hormozgan Province, Iran
2015
Asadpour, Gholamabbas
Evaluation of the geochemistry and hydrochemical quality of Bam salt dome located in southern Iran, was conducted in this study. Two composite samples from salt units were collected and analysed by XRD and XRF to determine their mineral and elemental compositions. Water samples were also collected from the only spring in the area and analysed for major anions, cations and some toxic elements. The results indicated halite as the major mineral present, while quartz, anhydrite and dolomite were present at minor levels. The presence of anhydrite and dolomite together with quartz had negative effects on edible salt quality. The dominant water type in the area was sodium-chloride. Negligible sulphate and calcium contents may be attributed to anhydrites detected in the geological texture of the study area. According to a Schoeller diagram, the water is not suitable for drinking. Concentrations of toxic metals in the salt sample were significantly higher than those in water samples. Such a result can be viewed as an opportunity to produce edible salts from the evaporation of spring water.
显示更多 [+] 显示较少 [-]Speciation of four heavy metals in agricultural soils around DraaLasfarmine area in Marrakech (Morocco)
2015
Yassir, Barkouch | Alain, Pineau
This study was carried out to 1. determine spatial variations of heavy metal deposition in agricultural soils of two rural communities (OuledBouAicha and Tazakourte) of about 5790 ha in a mining area near Marrakech city in Morocco; 2. to assess the extent of metallic pollution generated by the mining activity and; 3. to identify the key mechanism responsible for this contamination and its relation to mining activity. Soil pollution assessment was carried out on one hand by measurement of the total metal concentration and on the other hand by studying four heavy metals speciation of the studied soils. The chemical forms of four heavy metals in soils around DraaLasfar mine were studied by determining soil Cd, Cu, Pb and Zn species using standard solvent extraction and Atomic Absorption Spectrophotometric techniques. The chemical pools of the metals indicated that the metals were distributed into six fractions with most of them residing in the non-residual fractions thus suggesting how readily the metals are released into the environment. Considering that the metals occur in the most available forms, we suggested that it is most likely that the metals must have been derived from anthropogenic sources especially from the mining activity in the studied region.
显示更多 [+] 显示较少 [-]Radioactivity analysis in underground drinking water sources in Niger State University of Nigeria
2015
Njinga, Raymond | Ibrahim, Viva | Ishoryiyi, Ibiale
The activity concentration of gross alpha and gross beta particles in four samples of borehole drinking water consumed in Ibrahim Badamasi Babangida University (IBBU), Lapai, Niger State-Nigeria was measured, using a portable single channel gas free proportional counter (MPC2000B-DP) detector. This study focused on cancer related problems and the bio-data of the environment was discussed as well as the radiological effect of the water on consumers. Higher concentration of alpha and beta were observed in Hostel block A (DD) with values of 0.085 0.024 and 11.229 0.901 BqL-1, respectively. However, lower concentration of alpha and beta particles were observed in the Faculty of Management Science (AA) with values of 0.006 0.005 and 0.001 0.276 BqL-1, respectively. Out of the four sampling sites studied, only the Faculty of Management Science fall below the guideline levels of gross alpha (0.5 BqL-1) and gross beta (1.0 BqL-1) in drinking water, established by the World Health Organization. These results show that, consumption of groundwater from the other three major borehole sources, may pose significant radiological health hazards to the population.
显示更多 [+] 显示较少 [-]Assessment of indoor cancer linked to accumulated radiation dose from different types of television sets in dwellings
2015
Njinga, Raymond | Mamman, Sameul
Exposure to radiation from different types of television sets was measured to ascertain the levels of hazards posed to the human biological system. Measurement of the annual radiation dose hazards was performed using a halogen-quenched GM tube with thin mica end window having a density of 1.5 mg/cm2, effective window diameter of 0.360 inch and side wall of 0.012 inch thick. The GM tube was placed for 180 minutes and the sensor faced the screens of the various TV sets, one meter apart. The annual radiation dose ranged from 0.012 ± 0.006 mSv/yr for plasma-SONY to 0.13 ± 0.012 mSv/yr for SHARP and SAMSUNG 24 inch TV sets, containing cathode ray tubes. The annual doses from the 15 and 24 inch-LG TVs (manufactured with cathode ray tubes) were relatively low, with values of 0.031 ± 0.017 and 0.035 ± 0.005 mSv/yr, respectively. The 21 inch THERMOCOOL and PROTECH (with cathode ray tubes), produced annual doses of 0.110 ± 0.052 Sv/yr and 0.063 ± 0.002 mSv/yr, respectively. This provides an insight into the amount of radiation generated by different TV sets in households, on an annual basis. After some years of exposure to TV radiation, health complications such as carcinogenesis or other adverse cellular events may occur, due to cumulated (but does not always) doses which may result in DNA damage, to the human biological system.
显示更多 [+] 显示较少 [-]Vulnerability assessment of surface water quality with an innovative integrated multi-parameter water quality index (IMWQI)
2015
Sikder, Md. | Tanaka, Shunitz | Saito, Takeshi | Hosokawa, Toshiyuki | Gumiri, Sulmin | Ardianor, Ardianor | Uddin, Md. | Tareq, Shafi | Shammi, Mashura | Kamal, AK | Kurasaki, Masaaki
The development of a surface water evaluation index is a critical factor in the assessment, restoration and protection of stream water quality. Quantifying water pollution in specific grade using dominant parameters is important, as this can explain the current state of water pollution with accuracy. As a result, an integrated multi-parameter water quality index has been developed. It is based on the 10 most prevailing parameters (pH, conductivity, nitrate ions, phosphate ions, Escherichia coli number, cadmium, chromium, lead, copper and manganese) with a scale of 1 to 4, wherein the grades are classified into 1: good; 1.1-1.5: slightly polluted; 1.6-2.0: moderately polluted; 2.1-2.9: heavily polluted and 3.0-4.0: gravely polluted. The measuring stick used was according to the 2011 background values of the World Health Organization (WHO) in which a value of 0.1 was attributed for each, so that the final grade can be calculated. Water quality data were successfully fitted in an integrated multi-parameter water quality index to measure the river water level of pollution, and effectively represented every water bodies. This innovative index is able to quantify pollution with respect to seasons, geography and geomorphology of the respective rivers. Although operative, this index still lacks scientific integrity and as such, more synoptic experiments in the rivers of developing countries are recommended to attain a pragmatic feature.
显示更多 [+] 显示较少 [-]Evaluation of kinetics and adsorption isotherms for the Elimination of Pb(II) from aqueous solutions using Aloe barbadensis Miller Leaf Powder
2015
Malik, R | Lata, Suman | Singhal, Sushila
An adsorbent was developed from matured leaves of the Aloe barbadensis miller plant for removing Pb(II) from aqueous solutions. Adsorption was carried out in a batch process with several different concentrations of Pb(II) by varying amount of adsorbent, pH, agitation time and temperature. The uptake of the metal was initially very fast, but gradually slowed down indicating penetration into the interior of the adsorbent particles. The experimental data closely followed both Langmuir and Freundlich isotherms. A small amount of the adsorbent (1 g/50ml) could remove as much as 86% of Pb(II) in 35 min from a solution of concentration 0.3 mg/50ml at 25°C. The adsorption continuously increased in the pH range of 2.0–5.0, beyond which the adsorption could decrease up to pH 7.0 when the adsorption could not be carried out due to precipitation of the metal. The adsorption was exothermic at ambient temperature and computation of the parameters, ΔH, ΔS and ΔG, which indicated the interactions to be thermodynamically favorable.
显示更多 [+] 显示较少 [-]Cost Appraisal of Municipal Solid Waste Transfer to Disposal Site Using Visual Basic Program
2015
Olukanni, David | Iroko, Samuel | Aremu, Adeniyi
Collection of Municipal Solid Waste (MSW) accounts for a significant proportion of most municipal budgets, and has drawn some degree of researchers‟ interest. This study was conducted in Ota, Southwest Nigeria, to explore the use of Visual basic program as an innovative tool to select the most economic haulage system among three systems found in literature (conventional-, modified- and Stationary- hauled system) for collection and transfer of MSW to disposal sites. Factors that affect the costs of collection and transportation of waste such as: vehicle cost, total time spent on waste collection, and gross travel cost, were considered in the analysis. The result of the study shows that the stationary hauled method of waste collection is the optimal and economical method of collection. This method recorded a 56% and 43% reduction in total cost of daily travel per waste collection, as compared to the conventional and the modified systems, respectively. The application of visual basic program proffers implementable solutions to reduce the cost of MSW transportation to disposal sites. This would reduce travel time and costs of vehicle fueling, and increase the prompt collection of waste which would in turn facilitate the development of an aesthetically balanced and environmentally friendly municipality that would perhaps boost economic development.
显示更多 [+] 显示较少 [-]Driving patterns as a contributing factor to light-duty vehicular emission in the Kumasi metropolis
2015
Owusu- Boateng, Godfred | Nabena, Francis
Exhaust emissions contribute greatly to air pollution, the social cost of which may occur as danger to human health, attracting huge medical expenses, causing absenteeism and hence loss of productivity. These are incentives to reduce exhaust emissions to the barest minimum. Two major cities in Ghana, Accra and Kumasi, are struck by vehicular traffic jams especially during rush-hours and are grappling with the situation perceived to be worsened by driving pattern, a travel-related characteristic with a tendency to increase vehicular emission and hence, atmospheric pollution. Driving patterns were studied in the Kumasi Metropolis using questionnaires purposively administered to drivers who visited the Driver and Vehicles Licensing Authority. Parameters were analyzed with SPSS. Results indicate that drivers plied highway (90.0%), feeder (6.7%) and urban (3.3%) roads. Drivers (90%) had no knowledge of how driving patterns contribute to emissions, effect of idle and hot emissions and hot-and-cold starts dynamics. This could explain the failure of drivers to allow vehicle engines to stabilize for over 5 min and also to put off engines when stuck in traffic. Drivers changed speed as often as 4 times/km due to vehicle congestion and intermittent traffic lights, intersections and roundabouts. This may explain the difficulty in maintaining constant speed; thereby compelling drivers to exhibit frequent gear-changing behaviours as well as unstable and inconsistent speed profiles, as the commonest driving patterns. Such characteristics potentially increase energy consumption, emission level and abatement cost significantly and therefore, call for intensified educational programmes aimed at curbing this environmental peril.
显示更多 [+] 显示较少 [-]Purification of Heavy Metals Contaminated Groundwater by Electro-Coagulation Process Using Graphite Electrodes
2024
Muhibbu-Din, Eniola Ismail | Jimoh, Heekmah Oiza | Kehinde, David Pelumi | Tinuoye, Ifeoluwa Agnes
The application of the electro-coagulation process to the identified contaminated groundwater at Abala community, a suburb of Ilorin metropolis in Kwara state, Nigeria, is the subject of this study. The groundwater samples were electro-coagulated in a batch reactor of 2.5L containing 1 litre volume of contaminated groundwater for 1 hour per run using a DC power supply ranging from 10v to 20v at constant current 5amp and 2amp to 6amp at constant voltage 10v using graphite electrodes. The results revealed that electro-coagulation process can reduce turbidity, TDS, Electrical Conductivity, BOD, TOC, COD, and color by 97.3 %, 91.2 %, 91.1 %, 96 %, 99.7%, 99.7%, 79.9%, and 82.96 %, respectively. Through Atomic Absorption spectroscopy analytical study, the process also shows removal efficiency of Manganese, Iron, and Zinc of 82.96 percent, 70.0 percent, and 95.30 percent, respectively. The outcome of the electro-coagulation process met the World Health Organization (WHO), the United States Environmental Protection Agency (USEPA), and the Water Environment Partnership In Asia (WEPA) criteria for both drinking water and general industrial wastewater discharge guidelines. The electro-coagulation treatment for contaminated groundwater was efficient and effective, therefore it is recommended in this study for Nigerians.
显示更多 [+] 显示较少 [-]Various Elements Levels in Four Freshwater Mussels Shells Obtained from Gölbaşı Lake, Turkey
2024
Uğurlu, Erkan | Kumruoğlu, Levent Cenk
The aim of this study was to determine by SEM-EDS analysis of the surface morphologies of the periostracum and nacreous layer and to determine the sodium (Na), Strontium (Sr), manganese (Mn), potassium (K), titanium (Ti), iron (Fe), magnesium (Mg), cobalt (Co), copper (Cu), chromium (Cr), zinc (Zn) and nickel (Ni) metals levels in the shells of the mussel (Potomida semirugata, Unio terminalis, Anodonta pseudodopsis and Leguminaia wheatleyi) obtained from Gölbaşı Lake, Turkey. The results of the study, the representative SEM analysis and corresponding EDS spectra of the periostracum and nacreous layer of the shells of freshwater mussels confirmed the presence of elemental compositions, including CaCO3. P. semirugata and U. terminalis have the aragonite prismatic layer that shows typical polygonal organizing, regular and polygonal crystal forms, with hexagonal and coexisting rhombic shapes. However, while A. pseudodopsis has round aragonite crystals (Rc), L. wheatleyi has irregular crystal plate layers (Irc). CaCO3, detected strong Ca peaks as well as C and O peaks with Mg and Si peaks. On the other hand, sodium (Na) was found in the highest concentrations ranging from 82.30±0.040 to 155.37±0.050 μg/g, and its concentrations were also higher than those of other metals in all species. The most abundant elements in shells of four freshwater mussel’s species were Sr, Na, and Mn which ranged from 26.07±0.44-58.023±0.52 μg/g, 82.30±0.040-155.37±0.050 μg/g, and 6.06±0.044-9.66±0.053 μg/g respectively. To our knowledge, this is the first study in Turkey that is researched the different four freshwater mussel species in the Gölbaşı Lake, Turkey.
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