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A floating bed system vegetated with Oenanthe javanica was adopted in this study to treat two types of low-pollution wastewater (LPW): polluted river water (PRW) and treated domestic wastewater (DW). The water was treated for 111 days during the low-temperature season. The results indicated that the total nitrogen (TN) removal rates were higher in the DW groups than in the PRW groups during the initial 30 days. This difference may stem from the different C/N ratio of the influent. As the water temperature rose above 15.5 °C after March 12, the purification capability of nitrogen in the DW groups was enhanced, and the removal rates of TN were 89.8 and 76.8 % in DW and the control 2 at 111 days. Conversely, the performance of total phosphorus (TP) removal was robust during the initial stage of the experiment, despite receiving domestic wastewater with a relatively high N/P ratio (16:1). The TP removal rates in DW were as high as 91.5 % compared to 78.9 % in PRW at 30 days. At the same time, the N/P ratios of plant tissue were higher in the DW groups compared to that in the PRW groups. Plant uptake played a significant role in nutrient removal in the PRW groups (52.5 % for TN, 68.2 % for TP), followed by sedimentation. In contrast, plant uptake only accounted for 25.3 % of TN removal and 24.1 % of TP removal in DW. The results provide engineering parameters for the future design of an ecological remediation technology for LPW purification. [ABSTRACT FROM AUTHOR]

A novel LaMnO3 photocatalyst with perovskite structure was prepared by sol–gel combustion method. The combustion reaction mechanisms of nanocrystalline LaMnO3 powders were investigated by thermal analysis, infrared spectra, and X-ray diffraction technique. The results showed that the gels exhibited self-propagating behavior after ignition in air. Nanocrystalline LaMnO3 powders can be synthesized in one step by using sol–gel combustion synthesis. The photocatalytic activity of the LaMnO3 powders were evaluated by degradation of methyl orange (MO) in water under UV light irradiation. The results showed that the LaMnO3 powders exhibit good photocatalytic activities under UV light irradiation. The degradation percentage after 36 h on LaMnO3 powders was about 76%. [ABSTRACT FROM AUTHOR]

PLZST antiferroelectric ceramics were synthesized by the modified coprecipitation method. Effect of variations in the Ti4+:Sn4+ ratio on phase and properties were evaluated. The XRD patterns show that with the increasing of Ti4+ content, the structure of ceramics changes from tetragonal phase to rhombohedral phase and this was certified by the P–E hysteresis loops. The temperature dependence of dielectric constant of the ceramics was measured. Low frequency dispersion at room temperature disappeared when the temperature increased and the variation of Tm is not linear with the content of Ti4+. These unusual behaviors had been interpreted. [ABSTRACT FROM AUTHOR]