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This paper aimed to investigate the influences of surfactants on the nanoparticle transport behavior in soil. The transport behaviors of TiO2 nanoparticles (nTiO2) in soil with three different surfactants, including Triton X-100 (TX-100), sodium dodecylbenzene sulfonate (SDBS) and cationic cetyl trimethylammonium bromide (CTAB) were studied. Results showed that all the three surfactants decreased the mobility of nTiO2 in soil column, which were mainly caused by the strong adsorption of surfactants on soil and nTiO2. The inhibition order was as follows: CTAB>SDBS>TX-100. Combined effect experiments showed that when solution ionic strength (IS) increased, TX-100 or CTAB inhibited the mobility of nTiO2 in soil. However, the effect of SDBS on nTiO2 transport shifted from inhibition to facilitation when IS increased from 0.1 to 5mM. This was mainly attributed to the decreasing adsorption of SDBS on soil with increased IS, whereas the adsorption of TX-100 and CTAB was independent of IS. This innovative information motivates further insight into the role of surfactants on nanoparticle transport behavior in soil., (Copyright © 2015. Published by Elsevier B.V.)

Naphthalene decomposition in O2/N2 gas mixture with different O2 concentrations has been studied in a dielectric barrier discharge reactor at atmospheric pressure. O2 played an important role in the decomposition of naphthalene, especially in the selectivities of CO and CO2. There was an optimal naphthalene decomposition rate at an O2 concentration of about 3%. The COx selectivity increased up to 83.3% gradually with the O2 concentration increasing from 1% to 20%. Nanoparticles were found in the gas samples, concentrations of which can be reduced greatly through raising the O2 concentration. The decomposition byproducts of naphthalene were obviously different under different O2 concentrations. Some nitrogenous compounds reduced but some oxygenous compounds increased with increasing O2 concentration. The mechanism of naphthalene decomposition was proposed as that naphthalene was first initiated by dehydrogenation and oxidation, and then followed by deep oxidation to CO and CO2. [ABSTRACT FROM PUBLISHER]

Decane decomposition in Ar, N2, and O2/N2 gases was investigated using a pulsed dielectric barrier discharge reactor. The mechanism of decomposition was discussed on the basis of the products detected by gas chromatograph (GC) and GC-mass spectrometer techniques. Decane decomposition in Ar was initiated by dehydrogenation to form decane radicals, which were then dehydrogenated to yield decenes, lighter hydrocarbons. When O2 was present in the discharge space, decane radicals were oxidized to decanone, CO, and CO2. The oxidation mechanism of decane radicals to CO and CO2 was suggested due to the radical oxidation by O atoms and OH radicals. Nanoparticles were found in a size range of 5.5–160 nm. The sizes of the nanoparticles were different with the gas components due to the difference in the produced radicals in the discharge space. We proposed that the oxidation and nitridation of the decane led to the formation of the nanoparticles. [ABSTRACT FROM AUTHOR]

A miniaturized biosensor was developed for in situ noninvasive detection of glucose in sweat. The biosensor was composed of a pair of interdigital Pt-poly(L-lactic acid) (Pt-PLA) microelectrode arrays operating as the working and auxiliary electrode. The size of the sensor was 3.56 × 0.72 mm, while the width of the interdigital microelectrodes was 2.4 μm. The microelectrodes with densely packed coral-like Pt-PLA nanoparticles were fabricated using a multi-potential step deposition process. We investigated the influence of the Pt-PLA electrodeposition time on the morphology and electrochemical performance of the microelectrode. The optimized biosensor exhibited high electrocatalytic activity because of the synergistic effects between the Pt nanoparticles and PLA polymer matrix, including the electrooxidation of Pt on glucose, the adsorption of glucose by the PLA polymer, and the acceleration of the glucose dehydrogenation step. For glucose detection in sweat and tears, the linear concentration ranges were observed to be 0.001–33.76 μM and 33.76–1000 μM, with a low detection limit of 0.19 nM. The miniaturized biosensor exhibited high sensitivity and signal stability, and could be suitable for use in the long-term monitoring of sweat glucose levels in patients, athletes, and other subjects in various difficult environments. Image 1 • Interdigital microelectrode array-based microsensor for in-situ glucose detection. • Pt-poly(L-lactic acid) (PLA) microelectrodes were used. • High sensitivity to glucose in sweat and tears, with 0.19 nM detection limit, is shown. • Sensor could be attached to skin for in-situ glucose detection in sweat. [ABSTRACT FROM AUTHOR]

A dielectric barrier discharge (DBD) catalyst hybrid reactor with CeO 2 /γ-Al 2 O 3 catalyst balls was investigated for benzene decomposition at atmospheric pressure and 30 °C. At an energy density of 37–40 J/L, benzene decomposition was as high as 92.5% when using the hybrid reactor with 5.0wt%CeO 2 /γ-Al 2 O 3 ; while it was 10%–20% when using a normal DBD reactor without a catalyst. Benzene decomposition using the hybrid reactor was almost the same as that using an O 3 catalyst reactor with the same CeO 2 /γ-Al 2 O 3 catalyst, indicating that O 3 plays a key role in the benzene decomposition. Fourier transform infrared spectroscopy analysis showed that O 3 adsorption on CeO 2 /γ-Al 2 O 3 promotes the production of adsorbed O 2 − and O 2 2‒ , which contribute benzene decomposition over heterogeneous catalysts. Nano particles as by-products (phenol and 1,4-benzoquinone) from benzene decomposition can be significantly reduced using the CeO 2 /γ-Al 2 O 3 catalyst. H 2 O inhibits benzene decomposition; however, it improves CO 2 selectivity. The deactivated CeO 2 /γ-Al 2 O 3 catalyst can be regenerated by performing discharges at 100 °C and 192–204 J/L. The decomposition mechanism of benzene over CeO 2 /γ-Al 2 O 3 catalyst was proposed. [ABSTRACT FROM AUTHOR]

In this study, the impacts of ZnO Nanoparticles (NPs) on the microbial community in enhanced biological phosphorus removal (EBPR) system and its recoverability were investigated. High-throughput sequencing was applied to study the microbial community shift. Results show that the species richness in the EBPR system was reduced under the condition of ZnO NPs with high concentration (above 6 mg/L). Evolution analysis suggests that higher concentration ZnO NPs induced more microbial community shift. According to the analysis on genus level, Competibacter was more impressionable than Accumulibacter after exposure to 2 mg/L ZnO NPs. Nonetheless, this phenomenon could not be found as the concentration of ZnO NPs got higher (above 6 mg/L). Accumulibacter could reach to the initial level after recover for 20 days, whereas Competibacter could not recover even when the concentration of ZnO NPs was only 2 mg/L. Interestingly, although the phosphorus removal (P-removal) process was re-achieved, the microbial community in reactors was irreversible. [ABSTRACT FROM AUTHOR]