71 research outputs found

    Turbulent natural and forced convection in plumes and cavities

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    Nitrogen Mineralization in Selected Solid Waste Dumpsites in Port Harcourt, Nigeria.

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    Organic wastes in selected waste dumpsites in Port Harcourt were successively incubated with sandy-loam soils for days at 27ºC, under aerobic conditions. The results showed marked decrease in total nitrogen in the organic wastes which was observed as loss of nitrogen. The process of nitrification and incorporation of (NH4)2SO4 affected the pH which ranged from 5.9 to 7.9. The cumulative mineral nitrogen released increased with incubation periods and the rate of organic application up to 28th day, with a maximum release of 456.40ppm at a rate of 61MT/ha organic application. The release of mineral N decreased on the 56th day with a minimum of 177.80ppm ata rate of 60MT/ha of organic fertilizer only. An enriched organic. Waste soil and organic waste treated soil had a boosting effect on the release of mineral nitrogen. The amount of mineral nitrogen released was higher for (NH4)2SO4 fertilizer treated soil than for organic waste treated soil. The mineralization rate was found to decrease with increasing age of the waste dumps. It was therefore recommended that organic wastes should be sorted and composted for use as organic fertilizers to augment inorganic fertilizer

    Distribution of Lead and total Hydrocarbon in Tissues of Periwinkles (Tympanotonus fuscatus and Pachymelania aurita) in the upper Bonny River, Nigeria

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    The concentrations of lead and total hydrocarbons in the tissues of the periwinkles Tympanotonus fuscatus and Pachymelania aurita from the upper Bonny River were determined. The highest mean values of leadand total hydrocarbons were 9.45ìg/g and 1242.19ìg/g respectively. The results showed higher concentrations of lead and hydrocarbons in the creeks than in the open river. The concentrations of lead and total hydrocarbons measured at the control site were lower than the concentrations measured at the study sites. The concentrations of Pband THC were generally higher in the shells than in the tissues of periwinkles in the study areas. T – tests showed no significant difference in concentration between tissues and shells of the organism with high correlations (P 0.05, r = 0.9611 for THC). The relationships between the concentrations of Pb and THC in thetissues and shells were observed to follow linear and polynomial regression equations. The levels of Pb and THC were higher along the main river than the creeks as a result of dilution and flushing effects of current and volume of water. The levels of lead and total hydrocarbons in the periwinkles were attributed to emissions from automobiles using leaded gasoline for both land and sea transportation in addition to effluents, oil spills and surface coatings from moving and abandoned engine boats as well as industrial and domestic wastes containing metal parts andhydrocarbons. @JASE

    Assessment of Air Quality and Noise around Okrika Communities, Rivers State, Nigeria

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    The quality of air and noise levels around Okirika communities in River State were determined using portable hand held air monitors for air pollutants and anemometer for meteorological parameters. The parameters measured were suspended particulate matter, nitrogen dioxide, sulphur dioxide, hydrogen sulphide, ammonia, carbon monoxide, methane and volatile organic carbon, temperature, wind speed, wind direction and relative humidity. The results showed the highest concentrations of 0.007mg/m3 (PM1, dry), 0.036mg/m3 (PM2.5, dry), 0.286mg/m3 (PM7, dry), 0.378mg/m3 (PM10, dry), 0.503mg/m3 (TSP, dry), 1.7ppm (NO2, dry), 3.0ppm (CH4, dry), 0.2ppm (H2S, dry), 12.7ppm (CO, dry), 2.7ppm (NH3, dry), and 7.0ppm (VOC, rainy). The dry season concentrations of air pollutants were higher than the rainy season concentrations. The observed differences in mean concentrations of the air pollutants between the two seasons were not significant in case of TSP (P<0.05) but were significant (P<0.05) in other pollutants. The highest mean concentrations of the gaseous pollutants exceeded permissible limits and therefore pose environmental and health concern for the inhabitants of the area. The quality of air in the area is poor and need to be regularly monitored. @JASEMKeywords: Air quality, Okrika, Digital monitors, meteorology, Nois

    Heavy Metal Contamination of Soils and Vegetation around Solid Waste Dumps in Port Harcourt, Nigeria

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    Assessment of the levels of copper, zinc and lead in soils and vegetation around solid waste dumpsites in Port Harcourt and environs were carried out in 2005 using Atomic Absorption spectrophotometric technique. Physical parameters such as pH and particle size were also determined. The results show that the mean concentrations of copper in transect and profile soils and vegetation were 1.20 \ub1 0.83ppm, 2.57 \ub1 1.87ppm, 1.48 \ub1 1.61ppm respectively at the East \u2013 West road dumpsite and 2.42 \ub1 1.87ppm, 1.40 \ub1 0.61ppm, 1.39 \ub1 0.67ppm respectively at the Kaduna/Afam street dumpsite. The mean concentrations of zinc in soil and vegetations along the transect were 12.83 \ub1 4.65ppm, 2.68 \ub1 1.82ppm, 1.33 \ub1 0.64ppm, 0.80 \ub1 0.60ppm respectively at the Kaduna/Afam street dumpsite. The mean concentrations of lead in soils and vegetation were 0.26 \ub1 0.21ppm, 0.28 \ub1 0.24ppm, 1.48 \ub1 0.12ppm respectively at the East \u2013 West road dumpsite and 0.45 \ub1 0.37ppm, 0.20 \ub1 0.08ppm, 0.39 \ub1 0.17ppm respectively at the Kaduna/Afam street dumpsite. The order of occurrence of the heavy metals in the topsoils of the study areas was Zn > Cu > Pb. The levels of copper and zinc in soils from the waste dumpsite were significantly different (P <0.05) from soil sample elsewhere. The differences in the levels of copper, zinc and lead in soils and vegetations as well as dumpsite and outside dumpsite were not significant (P <0.05). The results indicate that solid wastes contributed to the levels of heavy metals in soils and vegetation. Also the concentrations of the metals in soils do not depend on the age of the waste dump rather, on the source, composition and the topography of the dumpsite. @ JASE

    QUALITY ASSESSMENT OF SOME SURFACE WATER IN ISRAEL AND NIGERIA FOR MULTIPURPOSE USAGE

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    Abstract: The quality and suitability of some surface water from Dead sea, Jordan and Galilee in Israel and Opobo, Asarama and Otamiri in Nigeria were assessed for potability and irrigation purposes by analyzing the water for physico-chemical parameters, Mg, Mn, Fe and Pb and irrigation indices using standard methods. The results obtained were compared with standard limits provided by World Health Organization and Standard Organization of Nigeria. The results were pH 5.70 -8.24; Electrical Conductivity 386.1µS/cm ->100,000 µS/cm ; Turbidity 0 -58.6 NTU; Salinity 0.9 ->40mg/l; TDS Mg 2+ exceeded permissible limits. The Total Alkalinity of Dead Sea, Jordan and Galilee exceeded permissible limit. The Turbidity of all the rivers except Opobo river were below permissible limit. The water in Israel had higher concentrations of Mn, Fe and Pb and exceeded permissible limits. The number of parameters that exceeded limits followed the decreasing order: Dead Sea > Galilee. > Jordan > Asarama > Opobo > Otamiri. Irrigation indices showed Soluble Sodium Percent values >50% and Kelly's ratio >1meq/l at Opobo and Otamiri rivers Also Sodium Adsorption Ratio of Opobo river was > 26. Thus Opobo and Otamiri rivers were considered unsuitable for irrigation. The surface water in the study areas especially in Nigeria should be regularly monitored to avoid serious pollution problems

    Nitrogen Mineralization in Selected Solid Waste Dumpsites in Port Harcourt, Nigeria.

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    Organic wastes in selected waste dumpsites in Port Harcourt were successively incubated with sandy-loam soils for days at 27\ub0C, under aerobic conditions. The results showed marked decrease in total nitrogen in the organic wastes which was observed as loss of nitrogen. The process of nitrification and incorporation of (NH4)2SO4 affected the pH which ranged from 5.9 to 7.9. The cumulative mineral nitrogen released increased with incubation periods and the rate of organic application up to 28th day, with a maximum release of 456.40ppm at a rate of 61MT/ha organic application. The release of mineral N decreased on the 56th day with a minimum of 177.80ppm at a rate of 60MT/ha of organic fertilizer only. An enriched organic. Waste soil and organic waste treated soil had a boosting effect on the release of mineral nitrogen. The amount of mineral nitrogen released was higher for (NH4)2SO4 fertilizer treated soil than for organic waste treated soil. The mineralization rate was found to decrease with increasing age of the waste dumps. It was therefore recommended that organic wastes should be sorted and composted for use as organic fertilizers to augment inorganic fertilizer

    Elemental Composition Analysis of Soil Samples from Bayelsa State in the Niger Delta Region of Nigeria

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    This study analysis the elemental composition and concentration of elements in the soils of the study area to ascertain degree of elemental enhancement in the soil resulting from anthropogenic activities with possible soil contamination, human health and environmental detriment. The study area was divided into eight grids and two soil samples per grid from over burden to a depth of 900mm was collected randomly in each grid. The samples were prepared using standard methods and analyzed with a linear accelerator. The number of detectable elements and their quantitative information was extracted from the elemental spectral signatures. . The result showed a high concentration value in some elements in the soil samples above values of elemental concentrations in soils from other reported studied region. In addition, Aluminium, Strontium, Barium, Gallium etc also showed an extremely high value in their concentration that exceeds the world wide mean range upper limit values in crustal soil study published. The study indicates some degree of potential contamination and therefore necessitate a regular periodic monitoring study to reduce potential health detriment to humans and the environment to as low as reasonably possible

    Assessment of Air Quality and Noise around Okrika Communities, Rivers State, Nigeria

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    The quality of air and noise levels around Okirika communities in River State were determined using portable hand held air monitors for air pollutants and anemometer for meteorological parameters. The parameters measured were suspended particulate matter, nitrogen dioxide, sulphur dioxide, hydrogen sulphide, ammonia, carbon monoxide, methane and volatile organic carbon, temperature, wind speed, wind direction and relative humidity. The results showed the highest concentrations of 0.007mg/m3 (PM1, dry), 0.036mg/m3 (PM2.5, dry), 0.286mg/m3 (PM7, dry), 0.378mg/m3 (PM10, dry), 0.503mg/m3 (TSP, dry), 1.7ppm (NO2, dry), 3.0ppm (CH4, dry), 0.2ppm (H2S, dry), 12.7ppm (CO, dry), 2.7ppm (NH3, dry), and 7.0ppm (VOC, rainy). The dry season concentrations of air pollutants were higher than the rainy season concentrations. The observed differences in mean concentrations of the air pollutants between the two seasons were not significant in case of TSP (P <0.05) but were significant (P <0.05) in other pollutants. The highest mean concentrations of the gaseous pollutants exceeded permissible limits and therefore pose environmental and health concern for the inhabitants of the area. The quality of air in the area is poor and need to be regularly monitored

    Distribution of Lead and total Hydrocarbon in Tissues of Periwinkles ( Tympanotonus fuscatus and Pachymelania aurita) in the upper Bonny River, Nigeria

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    The concentrations of lead and total hydrocarbons in the tissues of the periwinkles Tympanotonus fuscatus and Pachymelania aurita from the upper Bonny River were determined. The highest mean values of lead and total hydrocarbons were 9.45mg/g and 1242.19mg/g respectively. The results showed higher concentrations of lead and hydrocarbons in the creeks than in the open river. The concentrations of lead and total hydrocarbons measured at the control site were lower than the concentrations measured at the study sites. The concentrations of Pb and THC were generally higher in the shells than in the tissues of periwinkles in the study areas. T - tests showed no significant difference in concentration between tissues and shells of the organism with high correlations (P < 0.05, r = 0.9947 for Pb and P > 0.05, r = 0.9611 for THC). The relationships between the concentrations of Pb and THC in the tissues and shells were observed to follow linear and polynomial regression equations. The levels of Pb and THC were higher along the main river than the creeks as a result of dilution and flushing effects of current and volume of water. The levels of lead and total hydrocarbons in the periwinkles were attributed to emissions from automobiles using leaded gasoline for both land and sea transportation in addition to effluents, oil spills and surface coatings from moving and abandoned engine boats as well as industrial and domestic wastes containing metal parts and hydrocarbons. @JASE
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