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861.
In this presentation the results of an environmental study of New Karvali bay, in Kavala Gulf, North Greece, are announced. In the studied bay the main industrial activity is a Factory of Chemical Fertilizers (FCF) and its wastes have been discharged, practically without any treatment, to the sea. The study has shown that the concentrations of phosphates and nitrates in the area around the place of the waste ejection from the factory are relatively high. Other remarkable points of the study are the presence of fluoride anions in higher level than normal and the low concentration of heavy metals (Cu, Pb and Zn).  相似文献   
862.
During the years 1983–1986, a program aiming at monitoring water quality of the most crowded beaches, as well as assessing and minimizing pollution from certain land based sources was carried out in Rhodes and Cos. The program was directed towards inspections of treatment plants as well as laboratory analyses of treated effluents from large hotels. As a result, almost one in four hotels was obliged to construct a new treatment plant. In order to help personnel to improve plant efficiency through day‐to‐day maintenance a three day seminar was held in June 1985. Sea water quality parameters (total coliforms and E. coli) were found to be well below the limits set by E.E.C. directives.  相似文献   
863.
Complex formation of Cd2+ and Zn2+ with thiol derivatives has been investigated by differential pulse polarography. The binding of Cd2+ and Zn2+ with cysteine (CySH), glutathione (GSH) and the model peptide N‐acetyl‐cysteine‐methylamide (ASH) reveals different stoichiometry. Thus, Cd2+ forms 1:1 and 1:2 complexes with CySH while 1:2 and 1:4 complexes have been observed with GSH and ASH, respectively. Overall formation constants of Cd2+ with CySH (Iogβ 2 15.3) and with GSH (Iogβ52 14.4) have been estimated using competitive complexation with nitrilotriacetic acid (NTA). Investigation of competition between Zn2+ and Cd2+ for the thiol complexation has underlined the role played by the amino group in CySH for the stabilization of Zn complexes in contrary to Cd complexes.  相似文献   
864.
There exist a vast variety of data sources, either manual sources or computerized databases in the field of environmental chemicals. To facilitate the access and to retrieve the information wanted efficiently, we built up two “databanks of data sources”, one called “Databank of Manual Sources (DMAS)” and the other named “Databank of Databases (DADB)”. The set‐up of these databanks is explained and the load status statistics are shown. DMAS has 164 and DADB 106 hits.  相似文献   
865.
Simplified models provided information on the binding ability of organic acids with trace elements, the distribution of the formed organo‐heavy metal complexes at different pH, and the biological stability (biodegradation ability) of these complexes.  相似文献   
866.
The photodecomposition of diluted aqueous solutions of acridine and aminacrine in the presence of hydrogen peroxide was studied. Irradiation was carried out with a low pressure mercury vapour lamp. The kinetic model describes the photodegradation rate of the organic compound with respect to the technological parameters of the reactor and provides the reaction rate constants of hydroxyl radicals towards these two molecules. This model was extented to high hydrogen peroxide concentrations ([H2O2] > 200 μmol/l) by considering the reactivity of hydroxyl radicals towards hydrogen peroxide. This assumption allows us to define an optimal hydrogen peroxide concentration.  相似文献   
867.
The anticancer drugs: adriamycin, farmorubicin and mitomycin C greatly enhance the generation of hydroxyl radicals (HO.) from H2O2 in the presence of Co(II) ions (CoCl2) at pH 7.4 and 8, as measured by the deoxyribose assay. Catalase, hydroxyl radical scavengers (mannitol, cysteine, glutathione, thiourea, lactic dehydrogenase) inhibited the degradation of deoxyribose confirming that HO‐radicals are responsible for the degradation of the carbohydrate.  相似文献   
868.
The water leaching of diazinon (O,O‐diethyl‐O‐2‐isopropyl‐6‐methylpyrirnidin‐4‐yl phosphoroth‐ioate) through soil columns, was studied after column amendments with two well characterized humic acids (HA), in both liquid and solid state, and with the original raw organic materials, an oxidized coal and a leonardite, from which the HA were extracted. The percolation curves and the pesticide distribution over the soil columns showed that the addition of the raw organic materials and the solid HAs reduced significantly the mobility of the pesticide along the soil column. The oxidized coal was more effective than the leonardite original material; the different origin of the two carbon‐rich materials had an influence on the diazinon movement along the soil columns and such difference was enhanced with increasing addition rates. Moreover, incubation at field capacity for two months of the soil columns treated with raw oxidized coal and leonardite, largely enhanced the described effects on pesticide behaviour. A complete adsorption of diazinon on columns and a practical absence of leaching was observed when the HA from both materials were added in dissolved form. These results were explained with the swelling of the humic micelles in water and the enhanced availability of inner hydrophobic surfaces for the strong adsorption of diazinon. The water diffusion into the solid humic materials after two months incubation, also explains their high pesticide retention capacity. This work indicates the usefulness of either solid o dissolved humic substances, with the proper hydrophobic character, in preventing the vertical leaching of non‐polar organic pesticides in soils.  相似文献   
869.
The European INventory of Existing commercial Chemical Substances (EINECS) lists all substances which were on the European Community Market between 1 January 1971 and 18 September 1981. Substances on EINECS are known as ‘existing’ substances. The EINECS inventory was drawn up by the European Commission to meet the requirements of article 13 of Directive 79/831/EEC [1]. EINECS was published in the Official Journal of the European Communities in 1990 [2]. This paper describes how individual substances, impurities and mixtures were defined and dealt with when registered for the EINECS inventory. It is the first in a series of such papers.  相似文献   
870.
The movement of Lindane from application points at the surface soil towards the underground water and further transport within this compartment at the watershed‐soil catena scale, was inspected by measurements of the pesticide concentration in soil water at a controlled experiment where it was applied at a usual label dose. The concentrations of Lindane in soil water and the upper phreatic level were also measured at successive dates in samples obtained from a net of phreatimeter probes distributed over the area (1,500 km2) of the lower Colorado River basin (Bs. Aires, Argentina). The location of cultivated‐irrigated areas within the watershed was inferred from NDVI (Normalized Difference Vegetation Index)‐1 km‐10 day AVHRR images obtained at successive dates during the irrigation season. Feasible paths of underground gravitational water flows were computed by means of a GIS‐simulation model on the basis of local terrain slopes and aspects. The pattern of Lindane distribution over the basin was explained on the basis of the distribution of diffuse sources, the patterns of percolation and groundwater flows and the thermodynamic characteristics of the pesticide.  相似文献   
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