Topphein9921

The results illustrate that this newly developed material has low cost and rapid remediation of Pb2+ as good application potential. Bisphenol A (BPA) is widely used in industrial products. Due to the toxicity of this compound, and to comply with restrictions and regulations, manufacturers have progressively replaced it by substitutes. One of the main substitutes used is bisphenol S (BPS). Despite increasing use in many products, the effects of BPS on human health have been little investigated, and studies on percutaneous BPS absorption and particularly toxicokinetic data are lacking. However, the endocrine-disrupting activity of BPA and BPS appears comparable. Dermal contact is a significant source of occupational exposure and is the main route during handling of bisphenol-containing receipts by cashiers. Here, percutaneous BPS absorption was investigated and compared to that of BPA. Experiments were performed according to OECD guidelines. Test compounds dissolved in a vehicle - acetone, artificial sebum or water - were applied in vitro to fresh human skin samples in static Franz diffusion cells. Flux, cumulative absorbed dose and distribution of dose recovered were measured. BPA absorption was vehicle-dependent ranging from 3% with sebum to 41% with water. BPS absorption was much lower than BPA absorption whatever the vehicle tested (less than 1% of applied dose). However, depending on the vehicle 20% to 47% of the applied BPS dose remained in the skin, and was consequently potentially absorbable. Both BPA and BPS were mainly absorbed without biotransformation. Taken together, these results indicate that workers may be exposed to BPS through skin when handling products containing it. This exposure is of concern as its toxicity is currently incompletely understood. Hydroponic experiments with different cadmium (Cd) concentrations were conducted to explore the impacts of nutrient allocation on the Cd enrichment of Bermuda grass. The results demonstrated with the Cd concentration increase, the accumulation of nitrogen (N), phosphorus (P) and potassium (K) in roots, stems and leaves increased first and then decreased, while the accumulation of Cd had no significant difference. The biomass and N, P and K accumulation of CD1 and CD2 were significantly different from those of CD3 and CD4, but there was no significant difference in Cd accumulation. The root N, P and K distribution ratio of CD4 increased by 47.9%, 114.3% and 64.3% compared with those of CD2 treatment, the values of stem decreased by 29.4%, 22.4% and 17.2%, and the values of leaves increased by 15.8%, 19.8% and 23.6% respectively. The K ratio of root and leaf increased and that of stem decreased. Cd reduced N and K distribution ratio of stem and increased N and K distribution ratio of root and leaf. Pearson correlation analysis showed that the accumulation of N, P and K in stems was positively correlated with the accumulation of Cd in stems, and the accumulation of N, P and K in roots, stems and leaves were positively correlated with the Cd accumulation in leaves. Bermuda grass can schedule the nutrient allocation to adapt to the Cd absorption and enrichment in different organs under different Cd concentrations. In conclusion, nutrient allocation might affect the Cd accumulation of Bermuda grass. Hydrophilic VOCs (volatile organic compounds) were applied to explore their positive influence on the elimination of the single hydrophobic VOC in biotrickling filters (BTFs). Comparison experiments were carried to evaluate the effect of 4-methyl-2-pentanone and toluene on the performance of BTFs for n-hexane removal. The results showed that the existence of 4-methyl-2-pentanone improved the removal performance of BTFs at short gas empty bed contact time (EBRT) of 15 s and low temperature of 10 °C. The degradation of n-hexane in the presence of 4-methyl-2-pentanone was slightly enhanced with a loading ratio of 61. When the mixing ratio was greater than 4, toluene significantly promoted the biodegradation of n-hexane with toluene loading rate less than 10 g m-3 h-1. click here Additionally, The promotion effect was not only reflected in the contents of proteins and polysaccharides, but also in the growth rates of microorganisms in biofilms. This work discussed the detailed effect between n-hexane and hydrophilic VOCs in BTFs, which would contribute to develop a more economical method to improve the removal performance of hydrophobic VOCs in BTFs. In this study, Electrolytic Manganese Residue (EMR) was treated by EDTA-2Na/NaOH, ultrasonic etching, and hydrothermal reaction to obtain a novel nanocomposite catalyst (called N-EMR), which then was used, together with H2O2, to treat synthetic textile wastewater containing Reactive Red X-3B, Methyl Orange, Methylene blue and Acid Orange 7. Results indicated that the N-EMR had a nano-sheet structure in sizes of 100-200 nm; new iron and manganese oxides with high activity were produced. The mixture of a small amount of N-EMR (40 mg/L) and H2O2 (0.4 × 10-3 M) could removal about 99% of azo dyes (at 100 mg/L in 100 mL) within 6-15 min, much faster than many advanced oxidation processes (AOPs) reported in the literature. The elucidation of the associated mechanism for azo dyes degradation indicates that azo dyes were attacked by superoxide radicals, hydroxyl radicals, and electron holes generated within system. N-EMR was found to be reusable and showed limited inhibition by co-existing anions and cations. Moreover, high removal efficiency of azo dyes could happen in the system with a wide range of pH (1-8.5) and temperatures (25-45 °C), indicating that the process developed in this study may have broad application potential in treatment of azo dyes contaminated wastewater. Cd and Zn pollution was observed to often occur simultaneously in soils. However, previous studies focused on single heavy metal instead of Cd and Zn combined pollution. Castor (Ricinus communis) is considered to have great potential for contaminated soil remediation. The resistance of castor seedlings to heavy metals and the mechanism behind it remain unknown. In this study, the tolerance and accumulation ability of castor seedlings to Cd and Zn were investigated, and the accumulation mechanism involving the subcellular distribution in different tissues was further explored. The results on biomass and chlorophyll revealed that castor seedlings have good tolerance to the pollution with 0-5 mg/kg Cd and 380 mg/kg Zn, while not to the heavy pollution with 25 mg/kg Cd and 380 mg/kg Zn. The maximum accumulation concentrations of Cd and Zn, 175.3 mg Cd/kg and 386.8 mg/kg Zn, appeared in castor seedling root instead of stem and leaf, indicating that root played a significant part in accumulating Zn and Cd. The relative low dosage of Cd (0-5 mg/kg) promoted the accumulation of Zn in the subcellular component, while high dosage (25 mg/kg) inhibited the accumulation of Zn.