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971.
972.
973.
The methodology for estimating radiocaesium distribution between solid and liquid phases in lakes is applied for three prealpine lakes: Lake Constance (Germany), Lake Lugano (Switzerland) and Lake Vorsee (Germany). It is based on use of the exchangeable distribution coefficient and application of the exchangeable radiocaesium interception potential (RIPex). The methodology was tested against experimental data. Good agreement was found between estimated and measured 137Cs concentrations in Lake Constance and Lake Lugano, whereas for Lake Vorsee a discrepancy was found. Bottom sediments in Lake Vorsee are composed mainly of organic material and probably cannot be described in terms of the specific sorption characteristics attributed to illitic clay minerals.  相似文献   
974.
975.
976.
Water quality for 13 wells in El-Salaam, in a new city near Cairo, has been investigated. Those wells were dug specifically to provide water for a company specializing in broiler poultry production. The water was analyzed for the following bacteriological parameters: total bacterial counts (102–104), total coliforms (<1?102), fecal coliforms (<1?102) fecal streptococci (<1?103), aerobic spore formers (102–104) and total counts for Clostridia (<1?103) per 100 mL. Chemical parameters such as pH, sulphate, alkalinity, hardness, and pesticides indicate that the water is unacceptable for poultry production. This study illustrates the need for monitoring and maintaining the integrity of groundwater sources at El-Salaam.  相似文献   
977.
Physico-chemical, microbiological, ichthyotoxicological conditions and microalgae of Varenna stream were studied in samples taken in 12 collecting stations. The data reported indicate a marked deterioration proceeding downstream e.g. an increase of bacterial population, concentration of suspended solids, COD and variations in the composition and abundance of phytoplankton and periphyton.  相似文献   
978.
979.
I. Onofri 《Marine Biology》1987,95(1):153-155
In 1983 curred horns were detected in the rare Adriatic Sea fish Xyrichtys novacula (Linnaeus, 1758). Their dimensions and histological structures have been investigated. This observation, compared with previous occurrences, suggested the existence of heteromorphism within this species.  相似文献   
980.
The aim of the present study is to determine optimal adhesive interaction of phenolic compounds utilizing Candida maltosa and Rhodococcus erythropolis when adhering to kaolin, silicone, synthetic foil (Steriking R40) and fluorinated silicones, comparing cell and support surface hydrophobicity. In parallel, the interfering effect of detergents was investigated. Data obtained show that the less hydrophobic supports display high initial cell adhesion when contacted with the cell type with a lower surface hydrophobicity (yeast cell) but most stable yeast biofilms are those formed on highly hydrophobic fluorinated silicones. On the other hand, support hydrophobicity has no effect on bacterial cell detachment; however, bacterial biofilms are denser when growing on more hydrophobic supports. Both detergents interfere (independently on the cell type) with the early and late phases of biofilm development.  相似文献   
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