PFRs were the major analytes in all four microenvironments, followed by PBDEs > NBFRs this website > OCPs > PCBs. For all classes of analytes, relatively lower levels were observed in car and house dust from Pakistan than Kuwait. Levels of Sigma PBDEs, Sigma NBFRs and Sigma PFRs were higher in car dust, while Sigma OCPs and Sigma PCBs were higher in house dust from both countries. Sigma PFRs occurred at average concentrations of 16,900, 87,900, 475, and 2500 ng/g in Kuwaiti house
and car, and Pakistani house and car dust, respectively. For both countries, the profiles of analytes in car dust were different from those in the house dust. Different exposure scenarios using 5th percentile, median, mean, and 95th percentile levels were estimated for adult, taxi drivers and toddlers. For Kuwaiti toddlers, assuming high dust intake and mean and 95th percentile concentrations, the values computed for Sigma OCPs (1500 ng/kg bw/day) were higher than RfD values, while for Sigma PCBs (14.5 ng/kg bw/day) it was only two-fold lower than the corresponding RfDs. (C) 2013 Elsevier Ltd. All rights reserved.”
“We studied the electrical conductivity of nanocomposite layers of p-type conductive polymer poly(3,4-ethylenedioxythiophen)-poly(styrene sulfonate) (PEDT/PSS) and the n-type conductive
indium tin oxide (ITO) nanoparticles. A decrease in electrical conductivity of PEDT
with increasing ITO content up to a volume Selleckchem IACS-10759 fraction of about 16 vol % is observed. Above the volume fraction see more of 16 vol % the conductivity increases very steeply, most probably due to percolation between the ITO-nanoparticles. The analysis of characteristic PEDT infrared absorption bands yields a decrease in the bipolaron absorption and an increase in polaron absorption with increasing ITO content. The shift from bipolaron to polaron absorption is interpreted as “”undoping”" of PEDT due to a charge transfer between the p-type PEDT/PSS and the n-type conductive ITO nanoparticles. However, an estimation of the depletion length leads to the conclusion that depleted charge carriers only cannot explain the decrease in conductivity. Morphological changes of the system PEDT/PSS by incorporating of the ITO nanoparticles are considered as additional origin for the decrease in conductivity.”
“Sediment contamination remains a global problem, particularly in transitional waters such as estuaries and coastal lagoons, which are the recipients of chemicals from multiple near- and far-field sources. Although transitional waters are highly productive ecosystems, approaches for assessing and managing their sediment contamination are not as well developed as in marine and fresh waters.