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Organophosphate esters (OPEs) are widely used as flame retardants and plasticizers in industrial and commercial products. It is generally believed that OPEs in street dust mainly originate from road traffic and anthropogenic activities. The influence of atmospheric deposition is still unknown. In this study, leaves were employed as a novel passive air sampler to collect particle matters (PM) in 12 cities in the central province of Henan, China. Similar compositional profiles of OPEs were found in street dust and PM samples. The concentrations of individual OPEs in PM were 1–4 times higher than in street dust. Chlorinated OPEs concentration in PM shows a moderate correlation (r 2 = 0.538, p < 0.01) with that in street dust. The concentration of alkyl OPEs in PM has a high correlation (r 2 = 0.843, p < 0.01) with that in street dust. No significant correlation (r 2 = 0.133, p = 0.132) was found on the aryl OPEs concentrations between street dust and PM. Spearman correlation reveals that the emission sources of tricresyl phosphate (TCrP) and triethyl phosphate (TEP) may be different from other OPEs in dust and PM samples. Principle component analysis (PCA) provides an appropriate explanation that tris (2-chloroethyl) phosphate (TCEP), triphenyl phosphate (TPhP), tris (chloropropyl) phosphate (TCPP), tributyl phosphate (TnBP), and TEP in street dust and PM may be emitted from the same sources, suggesting that PM has a significant influence on the occurrence of OPEs in street dust. The estimated dry deposition fluxes of particle-bound OPEs show a significant correlation (R 2 = 0.969, p < 0.01) with OPEs concentrations in street dust, revealing that the input of atmospheric deposition could be a major source of OPEs in street dust. [Display omitted] • Spatial phytosampling was used to study the potential source of OPEs in street dust. • Leaves were used as passive sampler for comparative applications. • Most OPEs in PM had positive correlation with those in the street dust. • The input of atmospheric deposition is a major source of OPEs in street dust. [ABSTRACT FROM AUTHOR]

In this study, the gas-phase retention volume behavior of four highly volatile organophosphate esters (OPEs) on polyurethane foam (PUF) was studied using a frontal chromatogram. The breakthrough volumes (V B) of trimethyl phosphate (TMP), triethyl phosphate (TEP), tripropyl phosphate (TPrP), and tri-n-butyl phosphate (TnBP) were 0.33, 0.59, 10.5, and 32.4 m3, respectively. A significant negative correlation was found between the logarithm value of V B and the subcooled liquid vapor pressure (P L) with an r 2 of 0.905, indicating that the vapor penetration depends on both the volatility and total air volume. The enthalpy of desorption and vaporization (Δ H S −Δ H V) showed a significant difference between the tested OPEs and polycyclic aromatic hydrocarbons (PAHs), revealing that the strength of the sorption interaction of the tested OPEs vapor on PUF should be different from that of PAHs. The PUF-air partition coefficients (K PUF-air) of the tested OPEs ranged from 4.3 to 8.1, which were lower than those of three-to four-ring PAHs (7.02–10.2) and organochlorines (8.01–9.72), revealing that the partition of highly volatile OPEs on PUF is lower than that of low-volatile compounds. The PUF/XAD cartridge improved the absorption efficiency of the tested OPEs; however, its sorptive capacity was still limited. [Display omitted] • The breakthrough volumes of four high volatile OPEs on PUF column were determined by frontal chromatograms. • The breakthrough volumes of the tested OPEs are much lower than three to four ring PAHs. • There are significant differences in the sorption interaction on PUF between the tested OPEs and low volatile compounds. • XAD resins can improve the sorptive capacity for high volatile OPEs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Well-ordered layered manganese oxides were prepared using CTAB as guest molecule. • The layered structures of LMOs were dependent on the molar ratio of CTA+ to Mn. • Nanoconfinement is conducive to the interaction of pollutant with active species. • Constrained reaction environment promotes the production and enrichment of O 2 •−. Although manganese oxide is able to spontaneously oxidize organic contaminants in nature, the slow kinetics limit its application in engineered water treatment processes. Herein, we prepared well-ordered layered manganese oxides (LMOs) with adjustable interlayer distances using cetyltrimethylammonium bromine as a guest molecule, which were applied to degrade 3-chlorophenol as an example of organic pollutants. The ordering of the layered structure was found to be highly dependent on the molar ratio of cetyltrimethylammonium ion (CTA+) to Mn in the solutions (range 0–1.2). The maximum interlayer spacing (11.27 Å) was obtained at a molar ratio was 1.0 (LMO-1.0), which reduces the steric hindrance for 3-chlorophenol entering the interlayers. Additionally, the surface of the LMOs becomes more hydrophobic as their molar ratio increased, further favors adsorption of 3-chlorophenol on the LMO-1.0. The LMO-1.0 provides a constrained reaction environment, which increases the probability of 3-chlorophenol interacting with the active species as well as promotes the production and enrichment of superoxide radical (O 2 •−). Consequently, the degradation rate constant of 3-chlorophenol (0.446 min−1) is two orders of magnitude higher compared to the unconfined bulk phase (0.004 min−1). These findings provide useful insights into the development of Mn-based layered materials for water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • MATF and MRP enriched substantial heavy metals and PAHs from the environment. • MATF and MRP from actual artificial turf had significantly higher cytotoxicity. • EPFRs and ROS had limited contributions to the cytotoxicity of aged MATF and MRP. • Heavy metals and PAHs played important roles in the toxicity of MATF and MRP. Numerous micro-sized artificial turf fragments (MATF) and rubber particles (MRP) are generated and accumulated during the use of the artificial playing field. However, attention has rarely been paid to the potential toxic effects of MATF and MRP on sportsmen. In this study, the active components and chemical composition of aged MATF and MRP derived from laboratory photoaging and actual field sampling were detected, and their effects on cytotoxicity were examined correspondingly. Laboratory photoaging significantly increased environmental persistent free radicals (EPFRs), reactive oxygen species (ROS) abundances and oxidative potential (OP) levels on MATF and MRP, but they have limited cytotoxicity. Unfortunately, in the actual field, aged MATF and MRP with higher heavy metals and polycyclic aromatic hydrocarbons (PAHs) contents exhibited markedly higher cytotoxicity with the survival rate of cells of 78 % and 26 % (p < 0.05), although they had lower EPFRs and ROS yields. Correlation analysis revealed that the cell viability was closely linked to heavy metals of MATF (p < 0.05), and to organic hydroperoxide (OHP), PAHs and heavy metals of MRP (p < 0.05). By systematically considering the above results, heavy metals and PAHs enriched on MATF and MRP from the surrounding environment played the important role in the cytotoxicity, which was different from conventional perspectives. Our findings demonstrate that MATF and MRP associated with an artificial turf field contain potent mixtures of pollutants and can, therefore, be relevant yet underestimated factors contributing to the health risks. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses the problem of fault-tolerant many-to-one routing in static wireless networks with asymmetric links, which is important in both theoretical and practical aspects. The problem is to find a minimum energy subgraph for a given subset and a destination node such that there are node-disjoint paths from each node in the subset to the destination node in the subgraph. Firstly, we prove that the problem is NP-hard, and then propose two approximation algorithms: the minimum weight node-disjoint paths based (MWkNDPB) algorithm and the minimum energy node-disjoint paths based (MEkNDPB) algorithm. Extensive simulations have been conducted to show that proposed algorithms are efficient. [Copyright &y& Elsevier]