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1.
Total concentrations of Cd, Cr, Fe, Ni, Pb and Zn were compared from October 1996 to April 1998 in Physcia biziana (Massal.) Zhalbr. v. leptophylla Vezda and in the bark of Quercus ilex L. sampled from the same trees at an urban park. Trace metal concentrations were also measured in the bark covered by the lichen thalli. The lichens showed significantly higher Cr, Fe, Ni and Zn concentrations than both uncovered and covered barks. By contrast, both types of barks had higher concentrations of Cd and Pb than lichens. Trace elements showed a wide temporal variation of concentrations both in the lichens and barks. No relationship was found between the analysed matrices as regards the time course of trace element concentrations.  相似文献   
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The yellow-legged clearwing (YLC) Synanthedon vespiformis (Lepidoptera: Sesiidae) occurs in the Mediterranean and central Europe. It is polyphagous, boring into the woody parts of broadleaf species including forest trees as well as various Rosaceae species. S. vespiformis has been reported as an economically important pest causing severe injury to stone fruit plantations. Many attractants for sesiid species were discovered by random field screening using 2,13- and 3,13-octadecadienyl alcohols, acetates and aldehydes, including one for S. vespiformis; and about 20 sex pheromones of sesiids have been identified so far. In the present study we identified the natural composition of the sex pheromone of YLC laboratory reared females as a blend of E3,Z13- and Z3,Z13-octadecadienyl acetates, at a ratio of 4:1. We developed an efficient lure for monitoring the pest. Pheromone funnel traps with rubber septa, impregnated with 1 mg pheromone blend, efficiently captured males for 10 weeks. Suspension of Shin-Etsu? ropes containing a 2:1 blend of E3,Z13-18:Ac and Z3,Z13-18:Ac at 13.74 mg/ha/h, resulted in shutdown of trap catches in the treated plots and closely situated neighboring plots indicating that mating disruption is feasible.  相似文献   
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Environmental Science and Pollution Research - The photo-Fenton process was performed with four radiation settings to treat clinical analysis laboratory wastewater (CALWW) from a hospital, with the...  相似文献   
4.
Environmental Science and Pollution Research - This work is focused on the design and preparation of polymer inclusion membranes (PIMs) for potential applications for stannous cation sequestration...  相似文献   
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Extracellular, oxidative soil enzymes like monophenol oxidases and peroxidases play an important role in transformation of xenobiotics and the formation of organic matter in soil. Additionally, these enzymes may be involved in the formation of non-extractable residues (NERs) of xenobiotics during humification processes. To examine this correlation, the fate of the fungicide 14C metalaxyl in soil samples from Ultuna (Sweden) was studied. Using different soil sterilization techniques, it was possible to differentiate between free, immobilized, and abiotic (“pseudoenzyme”-like) oxidative activities. A correlation between the formation of metalaxyl NER and soil organic matter content, biotic activities, as well as extracellular phenoloxidase and peroxidase activities in the bulk soil and its particle size fractions was determined. Extracellular soil-bound enzymes were involved in NER formation (up to 8% of applied radioactivity after 92 days) of the fungicide independently from the presence of living microbes and different distributions of the NER in the soil humic subfractions.  相似文献   
7.
Waste management procedures in developing countries are associated with occupational safety and health risks. Gastro-intestinal infections, respiratory and skin diseases as well as muscular-skeletal problems and cutting injuries are commonly found among waste workers around the globe. In order to find efficient, sustainable solutions to reduce occupational risks of waste workers, a methodological risk assessment has to be performed and counteractive measures have to be developed according to an internationally acknowledged hierarchy. From a case study in Addis Ababa, Ethiopia suggestions for the transferral of collected household waste into roadside containers are given. With construction of ramps to dump collected household waste straight into roadside containers and an adaptation of pushcarts and collection procedures, the risk is tackled at the source.  相似文献   
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An international cooperative project on distribution of ozone in the Carpathian Mountains, Central Europe was conducted from 1997 to 1999. Results of that project indicated that in large parts of the Carpathian Mountains, concentrations of ozone were elevated and potentially phytotoxic to forest vegetation. That study led to the establishment of new long-term studies on ecological changes in forests and other ecosystems caused by air pollution in the Retezat Mountains, Southern Carpathians, Romania and in the Tatra Mountains, Western Carpathians on the Polish-Slovak border. Both of these important mountain ranges have the status of national parks and are Man & the Biosphere Reserves. In the Retezat Mountains, the primary research objective was to evaluate how air pollution may affect forest health and biodiversity. The main research objective in the Tatra Mountains was to evaluate responses of natural and managed Norway spruce forests to air pollution and other stresses. Ambient concentrations of ozone (O(3)), sulfur dioxide (SO(2)), nitrogen oxides (NO(x)) as well as forest health and biodiversity changes were monitored on densely distributed research sites. Initial monitoring of pollutants indicated low levels of O(3), SO(2), and NO(x) in the Retezat Mountains, while elevated levels of O(3) and high deposition of atmospheric sulfur (S) and nitrogen (N) have characterized the Tatra Mountains. In the Retezat Mountains, air pollution seems to have little effect on forest health; however, there was concern that over a long time, even low levels of pollution may affect biodiversity of this important ecosystem. In contrast, severe decline of Norway spruce has been observed in the Tatra Mountains. Although bark beetle seems to be the immediate cause of that decline, long-term elevated levels of atmospheric N and S depositions and elevated O(3) could predispose trees to insect attacks and other stresses. European and US scientists studied pollution deposition, soil and plant chemistry, O(3)-sensitive plant species, forest insects, and genetic changes in the Retezat and Tatra Mountains. Results of these investigations are presented in a GIS format to allow for a better understanding of the changes and the recommendations for effective management in these two areas.  相似文献   
10.
The cell phone market is developing at a rapid speed. Today there are more than 1.6 billion consumers in the world, and the lifetime of a cell phone is less than 2 years. As a consequence, there is an increase in the waste associated to this product, and many alternatives to the disposal of the cell phones are being studied, such as recycling which shows to be the most important. It is crucial to know what materials constitute the cell phone in order to carry out recycling and determine environmental and economical issues. This work presents an evaluation of the cell phone components, characterizing the raw materials and some properties of the recycled materials.  相似文献   
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