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Packaging materials are one of the largest contributors to municipal solid waste production. This paper evaluates the material impacts packaging policy in The Netherlands in the period 1986-2007. Five different voluntary agreements were implemented over this period to reduce the environmental impact of packaging. The analysis shows that among the investigated indicators, population statistically is the most robust indicator to estimate the packaging demand. A baseline is developed on the basis of population growth in The Netherlands, and is used as reference to evaluate policy impacts. The policy periods are evaluated on the basis of overall effectiveness compared to the baseline and target achievement. Dutch packaging policies have been effective to reduce the total packaging volume until 1999. After 2000, packaging consumption increased more rapidly than the baseline, suggesting that policy measures have not been effective. The largest increase in packaging recycling rates was achieved during the first policy period. More clear and consistent packaging policy measures and targets could improve the effectiveness of policies.  相似文献   
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Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation.  相似文献   
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Microwave and Fenton's reagent oxidation of wastewater   总被引:16,自引:0,他引:16  
We compared two H2O2 oxidation methods for the treatment of industrial wastewater: oxidation using Fenton's reagent [H2O2/Fe(II)] and microwave irradiation. Both methods were applied to the treatment of synthetic phenol solutions (100 mg L−1) and of an industrial effluent containing a mixture of ionic and non-ionic surfactants at high load (20 g L−1 of COD). The effects of initial pH, initial H2O2 concentration, Fenton catalyst amount and irradiation time were assessed. According to the oxidation of phenol, it has been found that the oxidation by Fenton's reagent is dependent on the pH, contrary to the microwave system, which is not influenced by this parameter. For both systems, a limiting amount of oxidant has been found; above this point the oxidation of phenol is not improved by a further addition of peroxide. The oxidation of the industrial surfactant effluent has only been successful with the Fenton's reagent. In this case, large amounts of ferrous ions are necessary for the precipitation of the ionic surfactants of the effluent, followed by the oxidation of the non-ionic constituents of the solution. Electronic Publication  相似文献   
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