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141.
The phthalat concentrations in soil samples from the Solling (Ecological Research Project Solling) were measured. The samples were collected from a beech and a spruce forest and aTrisetum flavescens meadow. The distance from the tree trunks and the different horizons were taken into consideration as well. Dimethylphthalat, diethylphthalat, dibutylphthalat, butylbenzylphthalat, di-(2-ethylhexyl) phthalat and dioctylphthalat were determinated using GC/MS. From the six phthalates investigated, four were detected in the samples. Dimethyl and diethylphthalat were found at very low concentrations in only one sample. Dibutyl- and di-(2-ethylhexyl)phthalat were detected in eight of 21 samples. No phthalates were found in the samples from theTrisetum flavescens meadow. Two of the nine samples from the beech forest showed phthalates. In six of the nine samples from the spruce forest phthalates were detected. Phthalate concentrations in the spruce forest were always higher than those found in the beech forest.  相似文献   
142.
The ranges of total polybrominated diphenyl ethers (PBDEs) in fish from four Swiss rivers were 0.8-240 ng/g in the bile and 16-7400 ng/g lipid in the liver. PBDE concentrations varied within each river and among the various rivers. Female fish tended to have higher concentrations in the liver, while the male fish had higher concentrations in the bile. From the resulting PBDE concentrations in fish it could not be infered that these contaminants contribute to the causes of the observed fish catch decline in Swiss rivers.  相似文献   
143.
Environmental Science and Pollution Research - It is important to establish the toxicity pesticides against non-target species, especially those pesticides used in commercial formulations....  相似文献   
144.
Environment Systems and Decisions - This paper proposes a framework to systematically evaluate and select attributes of decision models used in disaster risk management. In doing so, we formalized...  相似文献   
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The ceramiaceaen Polysiphonia urceolata rapidly degrades 14C(U)-L-leucine, added to sea water at a final concentration of 2.5x10-5 M/l, to isoamylamine. Under experimental conditions, 22% of the total radioactivity is found in the amine within 160 min. The amino acid decarboxylase responsible for this reaction has been characterized by Hartmann (1972a). No other mechanisms of leucine degradation could be detected, and the rate of 14C-incorporation into algal proteins is considerably lower than that of decarboxylation. The rate of decarboxylation is optimal at a leucine concentration of about 5x10-5 M/l. The amine formed is found in almost equal amounts in algal extract and environment. No further degradation of isoamylamine could be detected. The amine is a metabolic end product in P. urceolata. When 14C-isoamylamine is used as a tracer, relatively high amounts of amine are found in the algal extracts. It is supposed that the amine does not accumulate within the algal cells, but rather is bound to the acid polysaccharides of the cell walls by means of ionic exchange. The results strongly suggest that decarboxylation is the main route by which P. ureolata metabolizes amino acids from the environment which are substrates of the decarboxylase. The endogenous amino acid pool does not seem to be available to the enzyme as a substrate source. A possible ecological significance of amino acid decarboxylations is discussed.  相似文献   
150.
This report is based on several years of co-operation between our research groups and Danish biogas plants. Throughout the years, there has been a fruitful exchange of know-how and experiences in laboratory scale on the one hand and large scale on the other, leading to a better understanding of the principles of the anaerobic digestion process and to an optimization of its large-scale implementation. In order to get an overview of the current situation concerning the treatment of the organic fraction of municipal solid waste (OFMSW) in Denmark, interviews were carried out with operators of the biogas plants where OFMSW is treated and the municipality staff responsible for waste management. With the aim of fulfilling the governmental goal to treat 150,000 tons of OFMSW by the year 2004 mainly by anaerobic digestion, the different municipalities are investigating different concepts of waste collection and treatment. The quality of the OFMSW treated is the key to smooth operation of the biogas process including a high biogas yield and production of an effluent that is feasible for use as fertilizer on agricultural land. Comparison of the different concepts leads to the conclusion that source-sorting of OFMSW in paper bags is preferable to collection in plastic bags and successive separation of plastics in a waste processing treatment plant.  相似文献   
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