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21.
The results of a survey aimed at testing the hypothesis that the lichen Evernia prunastri, when transplanted in an agricultural area with high atmospheric NH3 concentrations, would respond to NH3 air pollution accumulating nitrogen in its thalli and showing changes in the concentration of assimilation pigments are presented. The results confirmed the hypothesis and showed that all lichen transplants accumulated nitrogen, suggesting that besides the release of atmospheric ammonia by animal stockfarms, the use of N-based fertilizers and the deposition of N-rich dust also may contribute to the high nitrogen availability to lichens in the study area. The result indicated that in the study area both the critical level of NH3 and the critical load of N for lichens are exceeded and physiological damage is to be expected in sensitive species. The results of assimilation pigments in E. prunastri, with a decrease in the concentration of chlorophylls a and b and carotenoids, as well as chlorophyll degradation to phaeophytin, confirmed this hypothesis. However, owing to the limited data set and pending further studies, these conclusions should be considered as limited to the study area.  相似文献   
22.
A phylogenetic analysis based on rDNA internal transcribed spacers (ITS) sequences was performed on 15 species of black corals assigned to the genera Antipathes, Stichopathes, Cirrhipathes, Rhipidipathes, Antipathella, Myriopathes and Cupressopathes recorded from the Messina Strait (Mediterranean Sea) and the Bunaken Marine Park (Celebes Sea, Indonesia). The phylogenetic analysis shows that the examined species are grouped in two main branches corresponding to the families Antipathidae-Aphanipathidae and Myriopathidae. While among the Myriopathidae species there is a very small genetic distance, the Antipathidae-Aphanipathidae clade shows a high degree of divergence between different genera. According to this study, the taxon Antipathes? sp. 3 characterised by a bush-like corallum without a well-defined axis, probably belongs to a new undescribed genus of the family Antipathidae.  相似文献   
23.
The present paper presents results from the analysis of 29 individual C2–C9 hydrocarbons (HCs) specified in the European Commission Ozone Directive. The 29 HCs are measured in exhaust from common, contemporary vehicle/engine/fuel technologies for which very little or no data is available in the literature. The obtained HC emission fingerprints are compared with fingerprints deriving from technologies that are being phased out in Europe. Based on the total of 138 emission tests, thirteen type-specific fingerprints are extracted (Mean ± SD percentage contributions from individual HCs to the total mass of the 29 HCs), essential for receptor modelling source apportionment. The different types represent exhaust from Euro3 and Euro4 light-duty (LD) diesel and petrol-vehicles, Euro3 heavy-duty (HD) diesel exhaust, and exhaust from 2-stroke preEuro, Euro1 and Euro2 mopeds. The fuels comprise liquefied petroleum gas, petrol/ethanol blends (0–85% ethanol), and mineral diesel in various blends (0–100%) with fatty acid methyl esters, rapeseed methyl esters palm oil methyl esters, soybean oil methyl or sunflower oil methyl esters. Type-specific tracer compounds (markers) are identified for the various vehicle/engine/fuel technologies.An important finding is an insignificant effect on the HC fingerprints of varying the test driving cycle, indicating that combining HC fingerprints from different emission studies for receptor modelling purposes would be a robust approach.The obtained results are discussed in the context of atmospheric ozone formation and health implications from emissions (mg km?1 for LD and mopeds and mg kW h?1 for HD, all normalised to fuel consumption: mg dm?3 fuel) of the harmful HCs, benzene and 1,3-butadiene.Another important finding is a strong linear correlation of the regulated “total” hydrocarbon emissions (tot-HC) with the ozone formation potential of the 29 HCs (ΣPO3 = (1.66 ± 0.04) × tot-RH; r2 = 0.93). Tot-HC is routinely monitored in emission control laboratories, whereas C2–C9 are not. The revealed strong correlations broadens the usability of data from vehicle emission control laboratories and facilitates the comparison of the ozone formation potential of HCs in exhaust from of old and new vehicle/engine/fuel technologies.  相似文献   
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Naphthalenesulfonates were found in water samples of the Italian river Bormida. Samples were collected at increasing distances from the point of emission of pollutants, and their analyses showed that these compounds can persist in river water and that they can propagate for considerable distances.  相似文献   
26.
Bivalve mollusks as filter-feeders concentrate in their digestive tissue microorganisms likely present in the harvesting water, thus becoming risky food especially if consumed raw or poorly cooked. To eliminate bacteria and viruses eventually accumulated, they must undergo a depuration process which efficacy on viruses is on debate. To better clarify the worth of the depuration process on virus elimination from mussels, in this study we investigated rotavirus kinetics of accumulation and depuration in Mytilus galloprovincialis experimentally contaminated. Depuration process was monitored for 9 days and virus residual presence and infectivity were evaluated by real time quantitative polymerase chain reaction, cell culture and electron microscopy at days 1, 2, 3, 5, 7, 9 of depuration. Variables like presence of ozone and of microalgae feeding were also analyzed as possible depuration enhancers. Results showed a two-phase virus removal kinetic with a high decrease in the first 24 h of depuration and 5 days necessary to completely remove rotavirus.  相似文献   
27.
The main characteristics of the electrostatic collection of fuel oil ash has been investigated at a pilot precipitator installed in a laboratory rig. The relationship between collection efficiency, dust concentration and air velocity is studied and the influence of the spacing between the collection plates on both efficiency and effective migration velocity is discussed. Emphasis is put on the high degrees of efficiency attainable under suitable operating conditions.  相似文献   
28.
Journal of Material Cycles and Waste Management - Palladium finds a remarkable use in electronic devices and catalysts; therefore, an efficient and complete recovery from the containing secondary...  相似文献   
29.
Among the compounds discussed for anti-microbial and anti-fungal use allicin (allylthiosulfinate, diallyl disulfide-S-monoxide), an active ingredient of garlic, has attracted considerable attention. The objective of this study is to determine the antifungal activity of a local garlic ecotype (Voghiera) extracts against different pathogens. Primary screening was carried out by the agar plates technique using ethanol garlic extract at four final concentrations against the following organisms: Alternaria alternata, Aspergillus spp., Colletotrichum acutatum, Didymella bryoniae, Fusarium culmorum, Fusarium avenaceum, Fusarium gramineareum, Gliocladium roseum 47, Pythium splendens, Rhizoctonia solani, Sclerotium rolfsii, Stemphylium vesicarium, Trichoderma longibranchiatum, and Botrytis cinerea. Secondary screening was carried out using a lyophilized and a spray-dried preparation at different concentrations against the organisms selected for the high inhibition garlic effect in the primary screening and compared with the commercial fungicides mancozeb and iprodione. The best results were observed for the spray-dried garlic compound that showed a good fungicidal activity at the concentration of 1.5 g/10 mL while lyophilized garlic at the same concentration exhibithed less inhibition activity against the four fungi analyzed in the second screening.  相似文献   
30.
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