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The aim of this study is to determine the quality of drinking water in the city of Pogradec, Albania. Daily samples were taken from six fixed points in the city. They were analyzed based on the standard methods for the following parameters: taste, odor, temperature, pH, conductivity (EC), turbidity, NO-3, NO-2, NH+4, chloride, and microbial load. The assessment of water quality was made using the water quality index (WQI) of the Canadian Council of Ministries of the Environment (CCME). The calculated value of CCME WQI by 87.81 indicates that the drinking water quality in the city of Pogradec is “good,” and that turbidity is the main problem in quality.
Fossil fuel resources are decreasing daily while biodiesel fuels are attracting increasing attention worldwide as blending components or direct replacements for diesel fuel in vehicle engines. In this experiment the seed oils of 30 Neem (Azadirachta indica. A. juss) biotypes were screened and evaluated for their physio-chemical parameters for oil content, biodiesel yield, density, viscosity, iodine value , free fatty acid and saponification value. Hence the neem seed oil tested in this current study could be the potential sources of raw material for biodiesel production.
Twenty two multifloral honey samples representing central western parts of Nepal were examined spectrophotometrically for their antioxidant properties and total phenol content. The modified Folin-Ciocalteu method was used to determine total phenol content and 2,2-diphenyl-1-picrylhy-drazyl radicals (DPPHO assay for antiradical activity. In all samples, physicochemical parameters like moisture, reducing sugar, sucrose, ash, free acidity and water insoluble matter were also measured according to harmonized methods of the International Honey Commission (IHC). The results of physicochemical analysis showed that all the values, except for moisture of a small number of high altitude honey samples, are in good agreement with the current Nepalese standard. The total phenolic contents of honey, collected from high and low altitude, ranged from 154.87 to 41.90 mg gallic acid equivalent (GAE/100 g) respectively, at corresponding antiradical activity using DPPH expressed as percent inhibition of 76.66% and 25.69%. The IC50 values of selected high altitude honey samples ranged from 56 to 72 mg/mL. The total antioxidant properties were correlated (P<0.01) between total phenol content and antiradical activity (r=0.992). The obtained results demonstrate that the Nepalese honey collected from high altitude region contained more antioxidants than honey of low altitude region.
This paper presents data on conductivity, pH, hardness, NH4-N, N03-N and Mn content in water of 49 selected wells, counts of TVC 20°C, TVC 37°C, TC, FC, FS and CP in water of 302 wells (0.3 - 31.5 m) in 30 localities, and from 8 natural springs in Wigry National Park in northeast Poland. Surveys were carried out twice: in spring and autumn 1995. Conductivity of well water was 360-1430 mS/cm3, pH 7.2-8.6, water hardness 172-544 mval/cm3, content of NH4-N 0-0.21 mg/dm3, N03-N 0-30.00 mg/dm3, Mn 0-1.00 mg/dm3. The majority of the surveyed wells had TVC 20°C. TVC 37°C, TC and FC counts exceeding permissible levels, and very high numbers of FC. Single wells had water containing CP. High numbers of these micro-organisms were present in shallow waters (less than 10 m) as well as in deep wells (more than 10 m). The degree of bacteriological contamination of well waters was usually lower in spring and higher in autumn. Higher bacteriological pollution of well water was often accompanied by higher N03-N concentrations. Natural springs were usually characterised by lower bacteriological contamination than well water.
The applied disinfectants affected the improvement of physicochemical parameters of litter by decreasing its moisture and pH. It was demonstrated that the addition of decontaminating agents to litter resulted in a beneficial decline in the microflora of poultry house air. The total count of mesophilic bacterium was reduced most effectively by means of a disinfectant, whereas the total number of fungi and moulds – by calcium oxide (CaO). But no differences were observed in ammonia concentration in the air of the hen houses examined. In poultry houses in which disinfectants were added to litter, the reported death rate and culling percentage were lower as compared to a control broiler house. Birds reared in a broiler house in which litter was disinfected with CaO achieved the highest European Index of Productivity (EIP).
The aim of this study has been to determine the response of cyanobacteria to the lake protection and restoration measures implemented in the littoral zone of an urban lake called Jeziorak Mały. The first investigations were conducted in 1996 and were resumed in 1997-2003, 2005 and 2013, following the installation of a separator and the creation of stone accumulation sites. Long-term changes in phytoplankton cyanobacterial proportions, abundance and biomass were analyzed in relation to environmental conditions at the sites in the littoral zone (S – separator pipes, K – sites with stones and R – sites with macrophytes). Relationships between cyanobacteria and water chemistry variables were analyzed by calculating the Spearman’s rank correlation coefficient, and then with canonical correspondence analysis (RDA). The results provided evidence that water temperature, total nitrogen and iron concentration (S, R), but also PO43- in spring (S,K) were the principal factors affecting cyanobacterial development. There was a significant decrease in the share, abundance and biomass of cyanobacteria coinciding with a decrease in conductivity and PO43- following the onset of lake restoration efforts. Changes in dominant species from the ones typical in hypertrophic lakes to those typically found in eutrophic lakes took place during the research. The modifications indicated a strong initial response of cynaobacteria to the restoration measures, but the situation stabilized in 2013, when cyanobacteria returned to their previous average levels. This suggests that the introduction of lake restortation measures contributed to the lake’s improved water quality and they should be retained for efficient lake management in the future.
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