خيارات البحث
النتائج 3241 - 3250 من 62,578
Effects of management of nitrogen fertilizers and conversion of cropping soils in fallow on nitrate pollution studie of the springs of roodt (Nospelt, Luxembourg). النص الكامل
1998
Weinzaepflen, Emmanuelle | Vander Borght, Paul | Tychon, Bernard
peer reviewed | A management of nitrogen fertilizers and a conversion of cropping soil into fallow were developed to reduce the nitrate pollution of spring exploit to supply with drinking water the southwestern Luxembourg. The methodological approach was based on in situ observations and includes a study of nitrates lost by leaching (measure of nitrogen profiles in experimental fields, use of vertical soil water cup ceramics) and study of the water quality of springs (measurements of nitrate concentrations). Since October 1995, the nitrate concentrations of polluted springs have been reduced by 25 mg l-1 due to the fallow and the reduction of nitrogen fertilizers.
اظهر المزيد [+] اقل [-]Deposition of aero-pollutants as a source for pollution of surface storages for water supply
1997
Ristic, R. | Kadovic, R. (Sumarski fakultet, Beograd (Yugoslavia))
Products of wet and dry deposition of aero-pollutants, reached by over-boundary or internal-boundary transport, are significant source of pollution, almost, whole territory of Serbia (Yugoslavia). Products of wet and dry deposition endangere surface storages in two ways: (1) directly, by deposition on surface storages; (2) indirectly, by deposition on surface of catchment areas, and further transporting through hydrographic system. In the period 1992-1996 investigations were carried out at some localities in Serbia (Yugoslavia). Their results show that recorded quantities significantly over pass MDK (maximal permitted quantity). Investigations included analysis of samples of precipitation (rain and snow), soil and sediment from hydrographic system.
اظهر المزيد [+] اقل [-][The recent flora of vascular macrophyta in the "Vrbas-Bezdan" and "Banatska Palanka-Novi Becej" canals [Serbia, Yugoslavia] as indicator of ecological characteristics and water quality]
1997
Stojanovic, S. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Vuckovic, M. | Zderic, M. | Stankovic, Z. | Kilibarda, P. | Lazic, D.
Inactivation of electoplanting sludge by vitrification
1997
Karlovic, E. | Dalmacija, B. | Kovacevic, S. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za hemiju)
The work is concerned with the possibility of inactivation of galvanic sludge formed in treatment of wastewaters of electroplanting plants by imbedding the waste in a glass material. Glass can be synthesized in contact with the waste by mixing and heating with glass constituents. The efficiency of inactivation was monitored by leaching the obtained materials. The results of leaching tests showed that the highest amount of electroplanting sludge (about 30%) can be inactivated by vitrification of the following mixtures: 26.3% of electoplanting sludge, 43.7% of sand, and 30.0% of Na2CO3 at 1000 deg C; 30% of galvanic sludge, 49% of sand and 21% of Na2CO3 at 1100 deg C.
اظهر المزيد [+] اقل [-]Microbiological and chemical characterization of waste mud from the waste water purification plants of the plant oil refinery
1997
Trivunovic, V. (Prirodno-matematicki fakultet, Novi Sad (Yugoslavia). Institut za biologiju) | Petrovic, O. | Jarak, M. | Galonja, T. | Petkovic, K.
This paper deals with microbiological and chemical analysis of waste mud, produced in wastewater purification plants of the oil refinery. After digest, mud is removed to the filter press. Compressed mud is placed and stored on the storage yard. Content of organic, anorganic and oil matters and also heavy metals contents were determined. Microbiological analysis comprised determination of total count of aerobic organotrophic organisms and many physiological groups of bacteria. As the indicator of the general biochemical activity, enzymatic (dehydrogenase and phosphatase) activities were determined. Waste mud was mixed with soil (chernozem) in 20%, 40% and 60% amount relations. Changes of activities and quantitative fluctuations of the present microflora were observed after 15 and 30 days. Gained results should enable assessing of using-ability of waste mud in soil-quality improvement, in the sense of its utilization as the fertilizer.
اظهر المزيد [+] اقل [-]Membrane enzymes as possible biosenzor for lead monitoring in water
1997
Nikezic, G. (Institut za nuklearne nauke Vinca, Beograd (Yugoslavia). Laboratorija za molekularnu biologiju i endokrinologiju) | Horvat, A. | Todorovic, S. | Vasic, V. | Vujisic, Lj.
In our earlier work, we have shown that enzymes from rat brain synaptosomal membranes, Na(+)/K(+)-ATPase and Mg(2+)-ATPase, are promising biological components of a biosensor for lead detection. In this work, we represent our results of investigation with the same enzymes as biological components for the biosensor in presence of Hg(2+) ions in water. It was established that IC50 for Na(+)/K(+)-ATPase and Mg(2+)-ATPase is 6.9 and 5.5 x 10E-6 M, and the percentages of inhibition are 96% and 77% respectively. We concluded that these enzymes could be the base for developing biosensors for the presence of Hg(2+) ion in water. Since these enzymes maintain a stable activity for a longer period of time, they could be appropriate as components of biosensors for monitoring water quality.
اظهر المزيد [+] اقل [-]Algological and saprobiological analysis of the river Dulenska [Serbia, Yugoslavia]
1997
Rankovic, B. | Simic, S. (Prirodno-matematicki fakultet, Kragujevac (Yugoslavia). Institut za biologiju)
During hydrobiological investigations of the river Dulenska (Serbia, Yugoslavia) in June 1996, algological samples were taken at this river. In the algae community are found 34 taxa from two divisio: Bacillariophyta (28) and Chlorophyta (6). While qualitative composition of the algae colony was relativelly uniformed quantitative one was changeable along the course of the Dulenska river. By saprobiological analysis, it was found that the quality of water was changing along the course of the river. At the upper and middle course of river the water belonging to the second class. At lower course of the river (below Rekovac) water quality was getfing worse and it belonging to the third class.
اظهر المزيد [+] اقل [-]Determination of the residues of organochlorine insecticides and polychlorinated biphenyls in heterogeneous system water-sediment
1997
Buzarov, D. (Univerzitet u Novom Sadu, Novi Sad (Yugoslavia). Prirodno-matematicki fakultet, Institut za hemiju) | Vojinovic-Miloradov, M. | Pavkov, S. | Macvanin, N.
The monitoring the content of organochlorine insecticides and polychlorinated biphenyls in heterogeneous system of water-sediment is of a primary interest for the researching of contamination of the aquatic ecosystem because of high bioconcentration factors of these compounds and their bioaccumulation in flora and fauna of the aquatic basin. The sampling of water and sediment were done in the Boka Kotorska Bay (south Adriatic Montenegro Seaside), and estuary Bojana - Ulcinj, Montenegro (Yugoslavia), in AuTumn of 1995. The residues of organochlorine insecticides and polychlorinated biphenyls were determined by gas chromatography, Varian 3400 with capillary columns OV-101, length 25 m, with ECD. The residues of isomers of HCH (hexachlorocyclohexane), DDT and PCB (polychlorinated biphenyls) were identified in all investigated samples.
اظهر المزيد [+] اقل [-]Analysis of drought characteristics using renewal processes
1997
Vukmirovic, V. | Petrovic, J. | Lazic, R. (Univerzitet u Beogradu, Beograd (Yugoslavia). Gradjevinski fakultet)
Drought characteristics (minimum flows, drought duration and volume deficit) of the Moraca river near Podgorica, Montenegro (Yugoslavia) are analyzed using the peaks over threshold method based on renewal processes. It is also shown that volume deficit and drought duration are highly correlated.
اظهر المزيد [+] اقل [-]Quality changes of aquifer a relating to plant production
1997
Belic, S. (Poljoprivredni fakultet, Novi Sad (Yugoslavia). Institut za uredjenje voda) | Belic, A. | Bugarski, R.
Neither soil nor water has very distinct function when seen in isolation. Therefore, analyses of water and soil can get real value only by their linkages. Taking into consideration irrigated land, water and soil interaction degree can cause different changes of soil, plants and aquifer A. All negative changes which are occur in the soil (in case of using unsuitable water quality for irrigation or applying of not rational fertilizers amount) have influence to the changes aquifer A quality. Interaction between soil and aquifer A are require investigation of groundwater quality changes relating to plant production, especially in irrigation. Intensity and type of aquifer A properties change, in case of different soil use in agricultural production, have been studying since 1991 at the Lysimetric Station Rimski Sancevi (Serbia, Yugoslavia). The results are point out satisfactory quality of aquifer A after irrigation with wastewater and well water, and applying of different mineral fertilizers amount. The soil capability to receive water with unsuitable quality, to influence their change and change of aquifer A quality as the final recipient, are showed by received results.
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