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41.
Different sources of pollution in Karasu Creek were investigated to obtain the water quality and ratio of contamination in this region. To achieve the main objectives of the present study, water samples were collected from Karasu Creek, starting from flow pattern at the upstream site of Akkaya Dam to the end of the dam, crossing the place where the Creek drains into. Dissolved oxygen, electrical conductivity, temperature and maximum/minimum pH were measured systematically for 12 months in the stations, where the water samples were collected. Chemical analyses of the water samples were carried out by using Cadas 50 S brand UV spectrometer to find out the Pb, Fe, Cu, Zn, Ni, Cr, Cd, S, F and Cn concentrations. These concentration were determined in μg/lt as 80–850; 180–4,920; 10–6,100; 440–25,530; 130–2,400; 120–280; 20–150; 214,250–1,113,580; 1,560–4,270 and 40–690, respectively. To determine metal levels of the water samples, multivariate analyses (element coefficient correlation, coefficient correlation dendrogram, hierarchical cluster analysis dendrogram, model summary and ANOVA) were used. The analyses yielded highly accurate results. There were positive correlations between some elements and their possible sources were the same. The stations which resembled each other along the creek were divided into three groups. The water quality of the creek was low and had toxic qualities. Eutrophication developed in Akkaya Dam along the creek. The source of pollution was thought to be industrial and residential wastes. Absolute (0–100 m), short distance (100–500 m) and medium distance (500–2,000 m) conservation areas should be determined in pollution areas along Karasu Creek and they should be improved.  相似文献   
42.
A three-step sequencing batch reactor (SBR) was used for nutrient removal from synthetic wastewater with different glucose-organic acid mixtures (1/1). Acetic, butyric, propionic and citric acids were used as organic acids along with glucose. The operation consisted of anaerobic, anoxic and oxic (An/Ax/Ox) phases with durations of 2/1/4.5h. Sludge age was kept constant for 10 days. Phosphate release and uptake rates were determined for different glucose-organic acid mixtures in the feed wastewater. Maximum phosphate uptake (8.1mgPl(-1)h(-1)) and release rates (2.23mgPl(-1)h(-1)) were obtained with the glucose-citric acid mixture. The highest (96%) percent phosphate removal at the end of the nutrient removal cycle (7.5h) was also obtained with the glucose-citric acid mixture while the glucose-acetic acid mixture resulted in comparable percent phosphate removal (95%).  相似文献   
43.
44.
The aim of this study is the treatment of Basic Red 29 (BR29) dye solution using hybrid iron-aluminum electrodes by electrocoagulation and electro-Fenton methods. The effect of current density, initial pH, supporting electrolyte, H2O2, and initial dye concentration on dye removal efficiency was investigated, and the best experimental conditions were obtained. Time-coarse variation of UV-Vis spectra and toxicity and chemical oxygen demand (COD) removal were also examined at the best experimental conditions. Both systems were found very successful for the removal of BR29 dye. The removal efficiency of >95 % for BR29 dye solution was reached easily in a short time. At the best experimental conditions, for the initial BR29 concentration of 100 mg/L, >95 % BR29 dye and 71.43 % COD removal were obtained after 20 and 40 min of electrolysis, respectively. Additionally, toxicity results for electro-Fenton treatment of 100 mg/L BR29 were also very promising. According to the results obtained, although electro-Fenton is more effective, both systems can be used successfully to treat textile wastewater including dyes.  相似文献   
45.
The temporal turbidity and surface temperature changes and effects of the 17 August 1999 earthquake in the İzmit Gulf, Turkey have been investigated using Landsat TM/ETM data. The gulf is in the Mediterranean–Black Sea transition climatic zone and is partially surrounded by green vegetation cover and degraded and densely urbanized-industrialized areas. Landsat TM/ETM data acquired in 1990–1999 confirms increase in turbidity. Turbidity is always low in the southern part and high in the northern part of the gulf, because the more urbanized and industrialized areas are located in the northern part. The Landsat-7 ETM data acquired in the same year (1999) shows seasonal changes in turbidity. Moreover, the two high turbidity and surface temperature anomalies, one of which is parallel to the 17 August 1999 earthquake surface rupture (east–west) and the other which is in the northwest–southeast direction were mapped from Landsat-5 TM data acquired the day (18.08.1999) following the earthquake in the east end of the gulf. On the basis of turbidity implying the sea bottom movement, it is possible to state that a second rupture in the northwest and southeast direction could have occurred at the sea bottom during the earthquake. The distribution of the seismicity centers and the orientation of the lineaments in the area support this finding.  相似文献   
46.
Journal of Material Cycles and Waste Management - The present study investigated the potential of utilizing the cutting dust waste generated in the sizing process of volcanic tuff stones as an...  相似文献   
47.
Environmental Science and Pollution Research - Various systems are increasing gradually to reduce environmental concerns carbon capture, use, and storage (CCUS) systems are one of the most...  相似文献   
48.
Spatial variability of salinity and alkalinity is important for site-specific management since they are the most important factors influencing soil quality and agricultural production. The objectives of this study were to analyze spatial variability in salinity and alkalinity and some soil properties affecting salinity and alkalinity, using classical statistics and geostatistical methods, in an irrigated field with low-quality irrigation water diverted from drainage canals. A field of 5 da was divided into 10 m x 10 m grids (5 lines in the east-west direction and 10 lines in the north-south direction). The soil samples were collected from three depths (0-30, 30-60 and 60-90 cm) at each grid corner. The variation coefficients of OM and sand contents were higher than other soil properties. OM had the maximum variability, with a mean of 1.63% at 0-30 cm depth and 0.71% at 30-60 cm depth. Significant correlations occurred between ESP, EC and each of Ca, Mg, K and CaCO(3) contents of the soils (p<0.01). Experimental semivariograms were fitted to spherical and gaussian models. All geostatistical range values were greater than 36 m. The soil properties had spatial variability at small distances at 60-90 cm depth. EC was variable within short distances at 30-60 cm depth. The nugget effect of ESP increased with soil depth. Kriged contour maps revealed that soils had a salinisation and alkalisation tendency at 60-90 cm depth based on spatial variance structure of the EC and ESP values. Spatial variability in EC and ESP can depend on ground water level, quality of irrigation water, and textural differences.  相似文献   
49.
The effects of tobacco waste (TW) application to the soil surface on the accumulation of Tobacco mosaic virus (TMV) in clay and loamy sand textural soils at various depths were investigated in two different fields. The tobacco waste had been found to be infected with TMV. Eighteen months after TW application to the soil surface, soils were sampled at 20 cm intervals through to 80 cm depth. The DAS-ELISA method was performed to determine infection of soil with TMV. The viruses persisted in clay soil for a long period compared with loamy sand soil. There was no accumulation of TMV at any depth of loamy sand soil in Experimental Field 2. TMV adsorption to soil particles in 0-60 cm depth of clay soil was determined in all TW treatments in Experimental Field 1. The highest ELISA Absorbance (A405) values in all treatments were determined in the 20-40 cm soil depth that had the highest clay content. ELISA A405 values of TMV at different depths of clay soil gave significant correlations with clay content (r = 0.793**), EC values (r = 0.421**) and soil pH (r = -0.405**). Adsorption of TMV to net negatively charged clay particle surfaces increased with increasing EC values of soil solution. Decreasing soil pH and infiltration rate increased adsorption of TMV to clay particles. Higher infiltration rate and lower clay content in loamy sand soil caused leaching of TMV from the soil profile.  相似文献   
50.
Environmental conditions affect human life in various ways. One of the domains of environmental conditions is buildings, and amongst them, a major and important group is the historical buildings. To keep this inheritance alive, one needs to determine the effects of environmental conditions. In this work, effects of lichens and NOx on 7 historical buildings in Erzurum were investigated. Historical buildings are readily available for lichen growth, which takes a long time, and this growth was investigated as a sample of environmental effect that occurs through long periods of time. NOx, main source of which is traffic in Erzurum, were considered as the environmental effect of daily life.  相似文献   
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