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A chemical characterisation of used batteries can give useful information to implement suitable recycling techniques and to estimate the flux of the different materials recovered. This work is aimed to provide quantitative data about the composition of mixed batteries (in particular, Ni–Cd, Ni-MH and Li-ion batteries) collected in a Northern Italian town in order to evaluate the feasibility of recovery processes applied to the selected material. The higher concentration of metals in the <3 mm fraction suggested that significant quantities of valuable elements could be recovered: in particular, for a kg of the <3 mm fraction deriving from disassembled batteries, about 390 g Ni and 330 g Cd can be recovered from Ni–Cd, 630 g Ni, 80 g Co from Ni-MH and 250 g Co, 110 g Ni, 120 g Cu from Li-ion ones. Leaching tests applied to the same fractions, to assess possible contaminant releases, resulted in low metal content in aqueous solutions (except for Al and Fe, the concentrations of all metals remained below 1 mg/kg). Even so, great care is required in all handling activities due to the high pH values of leachate solutions.  相似文献   
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Toxicity tests using adult specimens of Jenynsia multidentata were carried out during 96 hours in order to determine the lethal concentration (LC50) of endosulfan. Histological alterations were determined in gills and liver. Gill damage was quantified as secondary lamellae thickness. The 96 hr LC50 values were significantly different between males (0.719 microg x L(-1)) and females (1.317 microg x L(-1)). The sex difference was attributed to the dimorphism in the lipid content in females (2.16%) and males (1.79%). Histological alterations in gills included hypertrophy and lifting of the epithelium of the secondary lamellae and aneurisms. These alterations caused a significant increase of the secondary lamellae thickness in treatment versus control fish. Finally, reversible histological alterations (such as hydropic degeneration and dilation of sinusoids) were observed in the liver of exposed fish as well as an irreversible change such as necrosis at the highest concentrations.  相似文献   
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The behavior of 28 pesticides on two tomato cultivars with a different surface/weight (S/W) ratio of the berries (S/W, Birikino vs. Tombola) was studied, in order to provide appropriate indications about their persistence on crops reaching the pre-harvest interval (PHI). Quantitative analysis was performed using a GC MS/MS method. Birikino cv. (BIR) was a “cherry type tomato” with a double S/W ratio compared with Tombola cv. (TOM). The results showed a different pesticide behavior. Azoxystrobin, Boscalid, Bupirimate, Difenoconazole, Etofenprox, Iprodione, Mepanipyrim, Myclobutanil, Tebuconazole, Zoxamide, Metalaxyl M, Pyrimethanil, Tetraconazole, Benalaxyl, Cyprodinil, Fenamidone, Famoxadone and Fludioxonil immediately after treatments showed residues on BIR higher than TOM, and this behavior is consistent with its greater exposed surface. BIR showed higher decay rates of these pesticides during the whole trial, nevertheless residue averages remained higher than TOM reaching the time of harvest. Residues at the PHI were all below their Maximum Residue Levels (MRLs), but data indicated that they could exceed their legal limits especially if the above-mentioned active ingredients were employed more than once per crop cycle on cherry type tomatoes. As regards to Chlorpyrifos, Chlorpyrifos methyl, Triadimenol, Pyridaben and Tebufenpyrad, no different residual behavior related to S/W ratio of the cultivars was observed. Even in this case, residues at the PHI were all below MRLs. As for Cyfluthrin, Deltamethrin, Lambda cyhalothrin, Etoxazole and Cyproconazole, residues were lower than the limit of quantitation (LOQ) of the analytical method just after the treatment, according to their low doses of employment.  相似文献   
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