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61.
An increasing percentage of agricultural land in Germany is used for oil seed plants. Hence, rape has become an important agricultural plant (in Saxony 1998: 12% of the farmland) in the recent years. During flowering of rape along with intensive radiation and high temperatures, a higher production and emission of biogenic VOC was observed. The emissions of terpenes were determined and more importantly, high concentrations of organic carbonyl compounds were observed during this field experiment. All measurements of interest have been carried out during two selected days with optimal weather conditions. It is found that the origin or the mechanism of formation of different group of compounds had strong influence on the day to day variation of their concentrations. The emission flux of terpenes from flowering rape plants was determined to be 16–32 μg h−1 m−2 (30–60 ng h−1 per g dry plant––540–1080 ng h−1 per plant), in total. Limonene, α-thujene and sabinene were the most important compounds (about 60% of total terpenes). For limonene and sabinene reference emission rates (MS) and temperature coefficients were determined: βlimonene=0.108 K−1 and MS=14.57 μg h−1 m−2; βsabinene=0.095 K−1 and MS=5.39 μg h−1 m−2.The detected carbonyl compound concentrations were unexpectedly high (maximum formaldehyde concentration was 18.1 ppbv and 3.4 ppbv for butyraldehyde) for an open field. Possible reasons for these concentrations are the combination of primary emission from the plants induced by high temperature and high ozone stress, the secondary formation from biogenically and advected anthropogenically emitted VOC at high radiation intensities and furthered by the low wind speeds at this time.  相似文献   
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On the area of a former ordnance plant (‘Werk Tanne’, Clausthal-Zellerfeld, Germany), a field experiment for phytoremediation of TNT-contaminated soils has been carried out since May 1999. The concept is based on a stepwise degradation of TNT by white-rot fungi and mycorrhiza within the rhizosphere of site-specific seedlings. An appropiate site with contaminants in the surface-soil was prepared with a large-scale soil grader and subsequently divided into different experimental plots, including an uncontaminated control as well as a contaminated plot without treatment. Planting of the selected trees and shrubs (infected with mycorrhiza during nursery) and inoculation with wood chips (inoculated with white-rot fungi) is followed by a detailed monitoring of the experimental plots (chemical analyses, biotest-battery, ecological field indicators). For the evaluation of the results, multivariate methods are applied.  相似文献   
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Foreign companies and personnel are increasingly being employed for risky activities in process industry (Agro, Gas and Chemicals) in the north of the Netherlands. Against the backdrop of these developments, the need arose within the ‘VGM Noord-Nederland’ cooperation (health, safety and the environment in the Northern Netherlands) to further investigate experienced and detected problems, possible explanations, solutions and directions for preventing unsafe situations when working with foreign contractors and personnel. Because of little scientific information available on the topic, in autumn of 2004 an exploratory study was conducted into ‘working with foreign contractors and personnel’ in the process industry in the northern Netherlands under the auspices of VGM Noord-Nederland. In the course of the study, ten qualitative interviews were held with safety experts working at multinational companies in the agro, gas and chemical industry in the Northern Netherlands. The objective of the study was to gain sharper insight into the common problems and best practices experienced by these companies when working with foreign contractors and personnel in order to focus future joint activities towards these problematic areas. The study resulted in the identification of five problematic areas: communication, level of education, cultural differences, specific employment situations and cooperation between principal and contractor. All of these factors can be located within the ‘latent failure types’ or ‘basic risk factors’ described by the well known Tripod Model (i.e. Groeneweg, J., Lancioni, G.E., Metaal, N., 2002. Motivating for Safety, Leading by Example: moving from Compliance to Competence, Profshore Management Motivation Module, Stavanger) of accident causation. The results of the interviews are described for each problem area individually and are linked to state of the art scientific theory and models. Directions for ‘best practice’ examples are given and an indication for follow-up action is made.  相似文献   
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Environmental Science and Pollution Research - Although the development and application of nanomaterials is a growing industry, little data is available on the ecotoxicological effects on aquatic...  相似文献   
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In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC) data. The resulting disaggregated assets are validated and compared using census data of the residential building number on the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must, however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling aspects.  相似文献   
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Summary Gas chromatographic analyses of volatizable material from gaster intersegmental complex glands ofP. tridentata revealed the presence of linoleic acid, palmitic acid, methyl oleate, and several long-chain hydrocarbons as major constituents, which form an oily fluid mixture. The nest relocation communication ofP. tridentata is tandem running. Tandem following is mediated by pheromones as demonstrated by dummy experiments with isolated gasters and thoraces and with glass balls. The secretions of all gaster complex glands, as well as hind gut contents and metapleural gland secretions, were unable to evoke tandem following. Morphology and position of the glands, lack of pheromonal function, oily properties, low volatility, and lack of antibiotic effects of these secretions strongly suggest a function as lubricants for the ants' gastral segments.  相似文献   
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