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Concentrations of PBDE and BDE congeners in adipose tissue of East Greenland polar bears (Ursus maritimus) Texto completo
2007
Dietz, Rune | Rigét, Frank F | Sonne, Christian | Letcher, Robert J | Backus, S | Born, Erik W | Kirkegaard, Maja | Muir, Derek C G
Polybrominated diphenyl ethers (PBDEs) were analysed in adipose tissue from 92 East Greenland polar bears (Ursus maritimus) sampled during 1999-2001. Mean SumPBDE concentrations were 70 ng/g lipid weight (lw) (range: 22-192 ng/g lw) and showed no relationship with age or sex. Of the 32 analysed PBDE congeners; BDE47, BDE153, BDE99 and BDE100 dominated, and comprised 99.6% of the SumPBDE concentration. The SumPBDE concentration had a highly significant correlation with SumPCB, SumCHL, dieldrin, HCB and SumHCH concentrations. We found a seasonal pattern of median SumPBDE concentration with 1.2 to 1.8 times higher concentrations in March to July than the rest of the year. The seasonal variation also provides a clue to the seasonal exposure, bio-availability, toxic exposure and degradation. We suggest that future geographical PBDE data comparisons may not need corrections for sex or age, but such data sets should be corrected for seasonal variability, using the presented correctional trigonometric regression.
Mostrar más [+] Menos [-]Artificial neural networks in vehicular pollution modelling
2007
Khare, Mukesh | Nagendra, S. M. Shiva
"Artificial neural networks (ANNs), which are parallel computational models, comprising of interconnected adaptive processing units (neurons) have the capability to predict accurately the dispersive behavior of vehicular pollutants under complex environmental conditions. This book aims at describing step-by-step procedure for formulation and development of ANN based VP models considering meteorological and traffic parameters. The model predictions are compared with existing line source deterministic/statistical based models to establish the efficacy of the ANN technique in explaining frequent dispersion complexities in urban areas. The book is very useful for hardcore professionals and researchers working in problems associated with urban air pollution management and control."--Jacket.
Mostrar más [+] Menos [-]Color removal from raw water in drinking water treatment by coagulation with aluminium sulphate
2007
Ljubisavljevic, D.,Univerzitet u Beogradu, Beograd (Serbia). Gradjevinski fakultet
Removal of colour by coagulation in the drinking water treatment is described. Optimal results are obtained by pH correction. Buffer capacity of raw water is dominant on efficiency and rentability of the process.
Mostrar más [+] Menos [-]Enhanced coagulation and flocculation effects in drinking water treatment by flocculation sludge recirculation
2007
Agbaba, J.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Dalmacija, B.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Tubic, A.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Djurin, Z.,JKP Vodovod i kanalizacija, Zrenjanin (Serbia) | Pusic, I.,JKP Vodovod i kanalizacija, Zrenjanin (Serbia) | Ugarcina, S.,Prirodno-matematicki fakultet, Novi Sad (Serbia) | Roncevic, S.,Prirodno-matematicki fakultet, Novi Sad (Serbia)
This work considers the possibility of enhancing the iron (III) chloride coagulation process in natural organic matter removal by flocculation sludge recirculation. The results show that flocculation sludge has the potential to coagulate organic matter, and shows a dependence on the depth in the precipitator (0, 30 or 70 cm). Recirculation of flocculation sludge at a dose of 1.6 g/l (from a depth of 30 cm), results in a reduction of required coagulant by 25%.
Mostrar más [+] Menos [-]Industrial waste water refinement by precipitation treatment using dithiocarbamate: Changing process duration and pH effect on refinement efficiency
2007
Milenkov, Lj.,JKP Vodovod, Bor (Serbia) | Gardic, V.,Institut za bakar, Bor (Serbia) | Stankovic, S.,Institut za bakar, Bor (Serbia)
Stable complexes formation caused by usage of complexing agents as additive in plating solutions, made waste water treatment aggravated and expensive. The investigation results of samples that contain some cations expected in waste waters from this type of facilities, are presented in this paper. The precipitation of disolved heavy metals by neutralization, in the presence of strong chelators, do not give requested results. The dithiocarbamates are effective in complexing heavy metal ions forming insoluble compounds, with solubility far below that of the corresponding hydroxides. Inductively Coupled Plasma Optical Emission Spectroscopy is used for wastewater samples analysis. After the reduction of Cr6+ into Cr3+ ions and homogenization, dithiocarbamate is added. Modified neutralization process with unchanged retention time and pH 9.0 +/- 0.2 results the Law permitted wastewater quality.
Mostrar más [+] Menos [-]The utilization of the waste sludge produced during the process of waste water purification in Kolubara - Prerada as mineral-organic fertilizer in the process of biological reclamation of deposol in RB Kolubara DOO, Lazarevac [Serbia]
2007
Djikic, G.,Kolubara-Usluge doo, Lazarevac (Serbia) | Mandic, S.,Kolubara-Usluge doo, Lazarevac (Serbia) | Todorovic, N.,RB Kolubara doo, Lazarevac (Serbia) | Radisic, Z.,RB Kolubara doo, Lazarevac (Serbia)
During technological process of coal treatment and coal improvement in RB Kolubara waste water is produced in the waste water cleansing installation and waste mud is separated. The examination have been executed concerning agrochemical and mechanical properties of this material as well as the presence of heavy metals and phenol. Based on the results which appeard during examination, this materail can be included in the biological reclamation process as bonifactor and deposol fertilizer. Inserting such organic materials, the requared organogenic features are increased and the physical and mechanical characteristics of deposol substrate are improved. The economical effects are important for RB Kolubara as well as for Kolubara-Prerada. The most important contribution is to environmental protection and fulfilling the legal regulations for bringing back of degraded soil to the primary purpose.
Mostrar más [+] Menos [-]Environmental assessment within Boka Kotorska bay according to presence of sea urchin Paracentrotus lividus (Lamarck, 1816)
2007
Kascelan, S.,Institut za biologiju mora, Kotor (Montenegro)
Sea urchin, Paracentrotus lividus belongs to Echinoderms and has wide distribution as well in Meditarranean Sea as in the Adriatic Sea. It is very appreciated as object for testing negative impact of pollution, so can be used as bio indicator of sea water and sediments quality. Identification of the presence of this animal is done at 11 locations inside the Bay of Boka Kotorska (Montenegro), during 2005/2006. Obtained results show that the sea-urchin inhabit only outer part of Boka Kotorska Bay, where is open sea impact very strong, while inner part of the Bay is characterized by absence of Paracentrotus lividus, what can be caused by potential low quality of the sea water in the Bay.
Mostrar más [+] Menos [-]Monitoring of demersal resources in the Montenegrin coast and influence [of] hydrographic parameters on their distribution
2007
Joksimovic, A.,Institut za biologiju mora, Kotor (Montenegro) | Kasalica, O.,Institut za biologiju mora, Kotor (Montenegro) | Mandic, S.,Institut za biologiju mora, Kotor (Montenegro)
Monitoring of demersal resources in the Montenegrin coast start at 1997. We used commercial trawl vessels by monthly dynamic trawling. Processed total catch, estimated percentage part in total catch and CPUE (Catch per Unit Effort). We used standard fishery biology methods, estimation of population dynamic parameters, economical important fish, Red Pandora, Pagellus erythrinus, Red Mullet, Mullus barbatus, and crustaceans species, Pink shrimp, Parapenaeus longirostris. Also, we estimated relative and absolute biomass and MSY (Maximum Sustainable Yield) of this important demersal resources. This data give support to Ministry of Agriculture, Forestry and Water Management (of the Republic of Montenegro) to organize responsible exploitation of this resources. We finded center of higher biomass and relation to hydrographic factors, influence of income freshwater in the sea and increase of trophic level in this areas.
Mostrar más [+] Menos [-]Saprobiological characteristics of Skadar lake and Bojana river [Montenegro]
2007
Radonjic, D.,Institut za javno zdravlje, Podgorica (Montenegro) | Ceprnic, D.,Vodovod i kanalizacija, Herceg Novi (Montenegro)
Research of phytoplankton is conducted in different seasons during 2004 and 2005. River Bojana and Ada Bojana are analyzed on several locations. The objective of research is based on algae as reliable indicator of water quality and ecological condition of water. We would like to show the need for protection of these water ecosystems from permanent contamination, basically sewage waste. Saprobiotic index is determined by Gulyas Pal method. Pantle Buck method is used to calculate saprobiotic level. Chlorophyll A is analyzed by spectrophotometer. Presence of Cyanophytae was established.
Mostrar más [+] Menos [-]Concentration of metals (Fe, Mn, Cu and Pb) in aquatic macrophytes in the [water] reservoir Gruza [Serbia]
2007
Brankovic, S.,Prirodno-matematicki fakultet, Kragujevac (Serbia) | Pavlovic, D.,Prirodno-matematicki fakultet, Kragujevac (Serbia) | Topuzovic, M.,Prirodno-matematicki fakultet, Kragujevac (Serbia) | Milivojevic, J.,Institut za strna zita, Kragujevac (Serbia)
Investigation in this study should indicate to importance of aquatic macrophytes in accumulation of toxic metals in aquatic ecosystems and control of their pollution, as well as to indicate which plants are well hyperaccumulators and test species for remediation, in order of protection, regeneration and conservation of the Gruza lake as reservoir that is important for water supply and as particular natural ecosystem.
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