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61.
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   
62.
Objectives The purpose of this study was to determine electromagnetic fields, electric fields, humidity, temperature, and illumination levels in hairdresser salons located in the downtown area of Aydin, Turkey. Also some health problems which could be related with the occupational factors are evaluated. Materials and methods The study was carried out in 30 hairdresser salons, all of which had been registered within the past 5 years. Electric and electromagnetic fields, illumination, temperature and humidity measurements were determined for hairdryers, hood hairdryers and depilatory heaters in the participating salons. A brief questionnaire about characteristics and the health status of hairdressers and workplace conditions was prepared and administered to the hairdressers at the salons. Results The mean electric fields of hairdryers, hood hairdryers and depilatory heaters were determined as 518 ± 74, 1,123 ± 199, and 648 ± 146 in V/m, respectively, at 5 cm from the surface of each device. These appliances generate mean electromagnetic fields in excess of 0.25 μT at 5 cm: hand-held hairdryers, 5.0 ± 0.7 μT; hood hairdryers, 1.6 ± 0.3 μT; and depilatory heaters 1.9 ± 0.6 μT. Total average of cumulative electric and electromagnetic fields, measured at a distance of 90 cm from the surface of these three devices was calculated to be 98.8 V/m and 0.5 μT, in the participating salons. Conclusions This preliminary study suggests that physical environmental factors in the salons may be contributing to the health problems of the hairdressers, and the electrical equipments in the workplaces may have cumulative electric and electromagnetic effects.  相似文献   
63.
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   
64.
This paper explains briefly the conceptual framework of an ecosystem-based multiple-use forest management planning focusing on biodiversity conservation and participation. Some results from a case study were documented to realize the implementation of the concept. A strong liaison between the related institutions and major stakeholders and the effective use of Geographic Information System (GIS) and Remote Sensing (RS) are necessary. Effective participation is evident only with the involvement of enthusiastic and skillful stakeholders. A case study of ??neada, Turkey, supported the idea that participation as communication has better possibilities to promote multiple-use forest management than participation as information gathering. Primary challenges relate to the effectiveness of conservation program, availability of coherent biodiversity data, capacity building; awareness, training, and common understanding of biodiversity and protected area concept; coordination among the related institutions and stakeholders; and willingness and enthusiasm of authorities to accept and implement the concept.  相似文献   
65.
Specimen of freshwater fish (Cyprinidae) was collected from polluted and clean areas in dam Lake of Seyhan. Ten (n=10) fish were taken from each site. Liver preparations of fish from the two sources were comparatively assayed for glutathione-S-transferase (GST), lactic dehydrogenase (LDH), catalase (CAT), glucose-6-phosphate dehydrogenase (G6PDH), superoxide dismutase (SOD) and malondialdehyde (MDA). All systems were significantly (p<0.1) affected at the polluted site. The microscopic examination of the liver tissues of the fish living in the polluted area showed mononuclear inflammatory cell infiltration, cloudy degenerations, congestions and also micro- and macrovesicular fatty degenerations. These results provide evidence that both biochemical parameters and histopathological observations can be assumed as sensitive indicators of fish liver metabolism for polluted areas.  相似文献   
66.
The aim of this study was to determine the genotoxic risk of professional hairdressers in Ayd?n City, Turkey, through investigating the micronucleus frequencies in buccal mucosa epithelial cells. All the hairdresser working hairdresser area were included in the genotoxic risk group (GRG = 20) in Ayd?n City, Turkey. The control group (CG = 20) comprised healthy individuals matching the gender and age of the GRG. Buccal mucosal scraping from all the 40 subjects of GRG (10 women and 10 men) and CG (10 women and 10 men) was stained with Giemsa stain and observed under light microscope (×40) for the presence of micronuclei (M 10 N) and karyolysis, pyknosis, condensed chromatin, karyorrhexis, nuclear bud, and binucleates in the exfoliated epithelial cells. There are significance between the incidence of MN in GRG and CG (P = <0.005) using one-way ANOVA, Kolmogorov-Smirnov Z test, and Spearman Rank Correlation Tests.  相似文献   
67.
Environmental Science and Pollution Research - Cold chain, which affects human health and quality of life, is applied for temperature-sensitive and perishable products. Any problems occurring in...  相似文献   
68.
A food industry waste, almond shell, was pyrolyzed under three different environment static, nitrogen, and steam to produce bio-oil and its derivatives. The oil yield obtained at pyrolysis temperature of 600°C was 24.23% in a static atmosphere, whereas it increased to 27.25% and 33.05% in nitrogen and steam atmospheres, respectively. The bio-oil obtained under steam atmosphere is very efficient due to the production of high liquid and gas yields. Moreover, co-feeding steam during the pyrolysis altered the bio-oil structure by increasing the aliphatics and reducing the asphaltenes. Moreover, steam treatment also increases H/C and heating value of bio-oils. According to the obtained results, steam pyrolysis is an alternative option for future applications in refineries.  相似文献   
69.
Environmental Science and Pollution Research - Trihalomethanes (THMs), which is one of the major classes of DBP known to be highly cytotoxic and genotoxic, were formed and modeled under controlled...  相似文献   
70.
Environmental Science and Pollution Research - Rapid migration to cities and the increasing demand for housing negatively affect living areas. Furthermore, uncontrolled population growth,...  相似文献   
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