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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Preparation of flower-like TiO{sub 2} sphere/reduced graphene oxide composites for photocatalytic degradation of organic pollutants
In this study, novel flower-like TiO{sub 2} sphere (FTS)/reduced graphene oxide (rGO) composites (FTS-G) were synthesized via a hydrothermal method. The photocatalytic performance of the FTS-G composites was evaluated through the photodegradation of rhodamine B (Rh B) and trichloroethylene (TCE) under simulated solar light irradiation. The rGO to FTS ratio in the composites significantly affected photocatalytic activity. The photocatalytic activities of FTS-Gs in the degradation of Rh B and TCE were superior to that of pure FTS. Of all the FTS-G composites tested, FTS-G with 1 wt% rGO (FTS-G-1) had the greatest photocatalytic activity, while FTS-G composites with rGO contents over 1 wt% had lower photocatalytic activities. Additionally, it is expected that the synthesis of FTS with a high specific surface area and well-developed pore structure and simultaneous conversion of GO to graphene-like rGO without the use of strong reducing agents could be a promising strategy to prepare other carbon-based flower-like TiO{sub 2} sphere composite photocatalysts. - Graphical abstract: Schematic illustration of high photocatalytic activity for FTS-G composites. Display Omitted.
Remarkable improvement of visible light photocatalytic activity of TiO{sub 2} nanotubes doped sequentially with noble metals for removing of organic and microbial pollutants
Highlights: • Ordered TiO{sub 2} nanotubes (NTs) were synthesized using anodic oxidation. • TiO{sub 2} NTs were modified with Ag and Au NPs that settled separately to widen visible absorption. • TiO{sub 2} NTs modified with Ag and Au NPs is superior visible light photocatalyst. • TiO{sub 2} NTs modified with Ag and Au NPs shows superior antibacterial activity. • Annealing temperature played important role in photocatalytic activity of TiO{sub 2} NTs. - Abstract: The aim of this study was to show that Ag and Au nanoparticles (NPs) can have a synergistic effect on the photocatalytic and antibacterial activity of TiO{sub 2} nanotubes (NTs) under visible irradiation. TiO{sub 2} NTs were grown on Ti substrate by anodic oxidation and modified with Ag and Au NPs by dip coating and sputtering methods, respectively. The spherical 5–20 nm Ag and Au NPs were deposited on TiO{sub 2} NTs with diameter of 50–80 nm. In contrast to obtained results under UV irradiation, visible-light absorption range and visible photocatalytic activity of Ag and Au co-modified TiO{sub 2} NTs were much higher than TiO{sub 2} NTs without modification and TiO{sub 2} NTs modified with monometallic NPs. Photocatalytic activity of modified TiO{sub 2} NTs increased with increasing annealing temperature and appearing rutile phase. Antibacterial activity of Ag and Au-comodified TiO{sub 2} NTs against E. coli was noticeably more than that of TiO{sub 2} NTs modified with monometallic NPs.
Mitigating land pollution through pesticide packages – The case of a collection scheme in Rural China
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Maize cultivars relieve health risks of Cd-Polluted Soils: In vitro Cd bioaccessibility and bioavailability
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Summer ozone pollution in China affected by the intensity of Asian monsoon systems
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Short-term exposure to air pollution and infant mortality: A systematic review and meta-analysis
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Bioaccumulation of contaminants in Scarabaeidae and Silphidae beetles at sites polluted by coal combustion residuals and radiocesium
Anthropogenic contamination from coal-fired power plants and nuclear reactors is a pervasive issue impacting ecosystems across the globe. As a result, it is critical that studies continue to assess the accumulation and effects of trace elements and radionuclides in a diversity of biota. In particular, bioindicator species are a powerful tool for risk assessment of chemically contaminated habitats. Using inductively coupled plasma mass spectrometry (ICP-MS) and auto-gamma counting, we analyzed trace element and radiocesium contaminant concentrations in Scarabaeidae and Silphidae beetles (Order: Coleoptera), important taxa in decomposition and nutrient cycling, at contaminated and reference sites on the Savannah River Site, South Carolina, U.S. Our results revealed variability in trace element concentrations between Scarabaeidae and Silphidae beetles at uncontaminated and contaminated sites. Compared to Scarabaeidae, Silphidae had higher levels of chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn). Unexpectedly, concentrations of Cr, Cu, and Ni were higher in both taxa at the uncontaminated sites. Scarabaeidae and Silphidae beetles at the coal combustion waste site consistently had high concentrations of arsenic (As), and Scarabaeidae had high concentrations of selenium (Se). Of the 50 beetles analyzed for radiocesium levels, two had elevated radioactivity concentrations, both of which were from a site contaminated with radionuclides. Furthermore, our results suggest carrion beetles may be particularly sensitive to bioaccumulation of contaminants due to their trophic position and role in decomposition, and thus are useful sentinels of trace element and radionuclide contamination.
Progress in plasma doping semiconductor photocatalysts for efficient pollutant remediation and hydrogen generation
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