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Püspökszilágy Radioactive Waste Treatment and Disposal Facility (RWTDF) is a typical near-surface engineered repository designated to store low- and intermediate-level wastes from various institutes, research facilities and hospitals in Hungary. Two automatic combined 14C–tritium sampling units installed at the facility sample the air 2 m above surface. The one installed near the vaults detects tritium (T) activities two orders of magnitude higher than the far reference sampling unit. To localize the T emissions, 19 small absorption vapour samplers filled with silica gel were settled onto the ground surface. After the saturation of the silica gel, the water was recovered and its T concentration was measured with a low-background liquid scintillation counter. The absorption vapour samplers are cheap, simple and easy-to-use. We present the samplers and the T distribution map constructed from the data, which helps to localize the T emission.  相似文献   
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Regional Environmental Change - Historical land use may shape landscapes for centuries into the future, but it remains unclear how much land-use legacies affect contemporary land use. Knowing for...  相似文献   
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Environmental Chemistry Letters - Steroids are abundant in living organisms and are responsible for various biological functions. They are good candidates for inclusion complexes formation with...  相似文献   
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The presence of geranyl octanoate, previously found in pheromone gland extracts of Agriotes lineatus females, was also demonstrated in gland extracts of A. proximus females. Similar to A. lineatus, geranyl butanoate was present only in trace amounts in A. proximus female gland extracts. In air entrainment samples of female A. lineatus and A. proximus beetles, the relative ratio of geranyl butanoate and geranyl octanoate was higher than that in gland extracts. In addition, comparison of a segment of the mitochondrial cytochrome c oxidase subunit I gene of feral specimens of A. lineatus and A. proximus showed >99% similarity. Both pheromone profile and nucleotide sequence analysis delineate close relationship between the investigated taxa and postulate taxonomic revision. Further studies on sympatric populations of A. lineatus and A. proximus are underway to investigate and better understand possible processes of species diversification.  相似文献   
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Summary Blackbirds are usually multiple-prey loaders and forage mainly on the ground. We analysed the foraging behaviour of ten males in an urban park in Budapest during the breeding season from 1984 to 1986. At the end of April and in May blackbirds fed their nestlings mainly on earthworms (load type I). In this period the average scarching time and route were shorter, and the territories of the pairs tended to be smaller, than in June, when males in addition brought a great variety of invertebrates per load (load type II) to the young. The average dry weight and energy content of the two load types did not differ significantly. However, the average energy delivery rate (energy content/intervisiting time) and rate of energy gain (energy content/searching time) were higher when males collected earthworms, because intervisiting and searching times were shorter. The frequency distribution of searching times for load type I suggests that the encounter with earthworms was random. For load type II birds seemed to employ a fixed-mass foraging strategy. In June, the drier conditions reduced the availability of earthworms, and blackbirds extended their foraging areas.  相似文献   
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Environmental Science and Pollution Research - The aims of this work are to develop suitable analytical methods to determine the widely used anticonvulsant carbamazepine and 12 of its...  相似文献   
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