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Abstract: In recent years, wetland restoration measures have created extensive concerns globally. The theory and practice of restoring wetland vegetation diversity in wetlands through soil seed banks is discussed in this paper. A comparative study on soil seed bank and species composition in Yeyahu Wetland, Beijing, was conducted in 2007. Species and quantities of seeds from 12 sample sites were counted and measured by the seed-germinating method. After germination, 27 species belonging to 16 families and 23 genera were recorded, with an average of 11.75 species per sample site, and total average density of 24831.0individuals/m2. There were significant differences between the soil seed bank and vegetation in spring, summer and autumn, with similarity coefficients of 0.2620±0.0868, 0.2580±0.0778 and 0.1953±0.0452, respectively. Also in 2008, by using the seed bank technique, vegetation diversity was restored in a degraded wetland near Maying River of Yeyahu Wetland through the processes of spot selection, topographic surveying, water level monitoring, and vegetation management. The results showed that in the restored regions, both species and diversity coefficients of vegetation observably increased: 73.68% of the hydrophytic species we discovered were transplanted from provenance regions; germination of seeds in the soil lasted until late September; and many species completed their life history and produced new seeds to renew the seed bank. In addition, the results suggested that seed bank technique not only increased richness and multiplicity of vegetation, but also provided food chains with animal diversity in wetlands. [Copyright &y& Elsevier]

Abstract: The perovskite single-crystalline LaMnO3 nanocubes have been fabricated through a facile salt-assisted solution combustion process, using ethylene glycol as a fuel and corresponding nitrates as oxidants. The effects of the fuel-to-oxidant molar ratio and the fraction of added NaCl on the phase and microstructure of the products were investigated by X-ray diffraction, transmission electron microscopy and selected area electron diffraction. The possible mechanism about the effect of molten salt on morphological evolution of the as-prepared LaMnO3 particles in salt-assisted solution combustion synthesis was also discussed. [Copyright &y& Elsevier]

Abstract: Urchin-like CuO microspheres have been successfully synthesized via a simple water–ethyleneglycol (water–EG) mixed-solvothermal route at 100°C for 12h, employing cupric chloride (CuCl2) and potassium hydroxide (KOH) as starting reactants in the absence of any surfactant or template. The as-obtained product was characterized by means of powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and field-emission scanning electron microscopy (FESEM). It was found that the volume ratio of water and EG played an important role in the formation of urchin-like CuO microspheres. The UV–vis absorption and the photocatalytic degradation for organic dyes of the final product were also studied. [Copyright &y& Elsevier]

Abstract: The saturation magnetostriction of α″-Fe16N2 phase was evaluated by measuring the magnetostriction curve of Fe84.8N7.8B7.4 ribbon with α″-Fe16N2 nanocrystallites embedded in an amorphous matrix. The magnetostriction measurement was carried out at room temperature by means of the three terminal capacitance method. The prepared sample exhibits a saturation magnetostriction of 2.52×10−6. The saturation magnetostriction of α″-Fe16N2 phase is evaluated to be −19.1×10−6 according to a simple rule of mixtures. [Copyright &y& Elsevier]

External inputs and internal cycling are two pathways of nutrients to the aquatic macrophytes in the wetland ecosystem. Internal sources of nutrients include plant die-off and the decomposition of organic matter. In this study, we used a stable nitrogen isotope ( 15 N) enrichment experiment to track the timing and magnitude of cattail ( Typha angustifolia ) use of coontail ( Ceratophyllum demersum ) – derived nitrogen (CDN) in a freshwater wetland. Dry coontail powder enriched in 15 N (δ 15 N = 1259 ± 15‰) was buried in the soil close to the roots of cattail plants in field mesocosms at the Yeyahu National Preserve, Beijing, China, from July 22 to September 30, 2014. Different parts (roots, rhizomes, stems, leaves and leaf apexes) of the cattail plants were collected at day 0, 14, 28, 42, 49, 56, 63 and 70 for stable isotope analysis. Results reveal uptake of the nitrogenous nutrient from coontail detritus by cattail four weeks after being exposed to CDN. The maximum uptake rate for excess 15 N in roots, leaves, stems, rhizomes and leaf apexes were 1.55 ± 0.84, 0.69 ± 0.11, 0.33 ± 0.08, 0.14 ± 0.11, 0.06 ± 0.02 mg 15 N m −2 . The root system is the largest pool of nitrogen in cattails, which serves as the source of nitrogen for other plant parts. The uptake rate per unit biomass was highest in the leaf apexes. [ABSTRACT FROM AUTHOR]

• Wetland Degradation Index (WDI) was constructed on a pixel-by-pixel basis. • WDI incorporates lake shrinkage index (LSI), vegetation/soil degradation index. • LSI considers long-term continuous variations of water extent with Landsat images. • First assessment on lake wetland degradation in Bashang Plateau, China. Continuous monitoring of wetland dynamics and regional-scale assessment of wetland degradation are important to understand wetland ecosystem processes and to formulate restoration measures. The lake wetlands in Bashang Plateau play vital roles in providing essential resources and maintaining biodiversity in North China, while they were not fully investigated in previous studies. In addition, previous studies on wetland degradation assessment mostly relied on wetland area change every five or ten years. Continuous dynamics of wetlands was rarely considered. In this study, we developed a new wetland degradation index (WDI) to assess lake wetland degradation in Bashang Plateau based on time series Landsat imagery from 1985 to 2020 on Google Earth Engine platform. WDI integrates three indicators, namely lake shrinkage index (LSI), vegetation degradation index (VDI) and soil degradation index (SDI), which represents hydrodynamics of wetland inundation, vegetation, and soil conditions of wetlands, respectively. Different from previous research that utilized remotely sensed image to extract wetland every five or ten years, the LSI considers time-series continuous dynamics of lake water inundations and the transitions between water and non-water on a pixel-by-pixel basis. Our results showed that small lake wetlands with area less than 8 ha are dominant in Bashang Plateau. Both the number and the area of lake wetlands showed large interannual variations. The number (area) of lake wetlands reached 1715 (31,419 ha) in 1995–1996 and were only 493 (7,717 ha) in 2009–2010. The total area of the lake wetlands in 2019–2020 was only around 1/3 of that in 1995–1996. The LSI, VDI, SDI, as well as WDI demonstrate large spatial variations among the lake wetlands and within the lake wetlands. Wetlands in the western and central subregions experienced more severe degradation than those in the eastern subregion, and the edge of the wetlands normally showed more severe degradation. The resulted degradation grades are consistent with our field investigations. Among the 11 counties in Bashang Plateau, Zhangbei (ZB) county in the western subregion has the largest area with severe and very severe degradation grades. Degradation of lake wetlands was mainly associated with groundwater level declination which was induced by anthropogenic activities and economic development. The proposed WDI in this study can be widely applicable for regional-scale wetland degradation assessment using remote sensing techniques and thus further help decision making in lake wetland conservation and restoration. [ABSTRACT FROM AUTHOR]

Abstract: An integrated wetland system (IWS) including constructed wetlands (CWs) and modified natural wetlands (NWs) for wastewater treatment to replenish water to wetlands located at the Beijing Wetland School (BWS) in Beijing, China, is presented in this paper. The synergistic effects of CWs and NWs on treated water quality are investigated. The IWS is proved to be an effective wastewater treatment technique and a better alternative to alleviate the water shortage for conservation of wetlands based on the monitoring data obtained from October 2007 to 2008. The results show that CWs and NWs play different roles in removing contaminants from wastewater. The COD removal efficiency in CWs is higher than that in modified NWs, whereas the modified NWs can compensate for the deficiency of CWs where a stable and sufficient rhizosphere is not fully formed in the start-up period. All removal rates of COD, TN, and TP in CWs and modified NWs vary from 50 to 70%, while the total removal rate of COD, TN, and TP in IWS is about 85–90%. The operational results show that the maximum area loading of organic pollutants in modified NWs (65kg/had) is slightly higher than the empirical one (60kg/had) recommended by for free water surface wetlands. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pure monoclinic LaPO4 form was rapidly obtained by a simple oil-bath route at 120°C for 30min. [•] The integration of Eu3+ ions into LaPO4 matrix did not vary the phase of the final La1 − x Eu x PO4. [•] The shape and size of the La1 − x Eu x PO4 were markedly affected by the content of Eu3+ ions in LaPO4 host. [•] The as-prepared La1 − x Eu x PO4 microstructures exhibited good photoluminescence properties. [ABSTRACT FROM AUTHOR]

Abstract: Sn1−x RE x O2−x/2 (RE=Y, La, Gd and Nd) nanorods have been prepared by annealing the as-obtained products from microwave-induced KCl-assisted solution combustion reaction. The phase evolution in the synthesis process was investigated by an X-ray diffractometer. Accordingly, the possible growth mechanism of Sn1−x RE x O2−x/2 nanorods was discussed based on oriented attachment by polar forces. The results showed that the Sn0.8Y0.2O1.9 nanorods were rutile-structured single crystals with 8–12nm diameter and 100–200nm length. Proper addition of KCl into the redox mixture solution is critical to the formation of Sn1−x RE x O2−x/2 nanorods. The approach is convenient, inexpensive and efficient for the high yield preparation of Sn1−x RE x O2−x/2 nanorods. [Copyright &y& Elsevier]

Abstract: The transport of dissolved inorganic nitrogen in wetlands was investigated in the Yeyahu National Preserve of Beijing, China, from July to December 2011. Stable isotope of nitrogen (15N) as NH4 + was added to experimental mesocosms vegetated by seven common wetland plants. The 15N abundance in soil and various plant parts were measured at prescribed time intervals during the 49-day experimental period. Rapid 15N enrichments were found in soil and aquatic plants during the first sampling event at day 3 and typically increased linearly during the experimental period. Highest 15N enrichment was found in submerged plants, followed by emergent plants and soil. No differences in δ 15N values were found among leaves and stems of all submerged plants (Potamogeton pusillus, Potamogeton perfoliatus, Najas marina, Ceratophyllum demersum), suggesting that these plant structures are equally effective in nitrogen assimilation. The roots of P. perfoliatus displayed the lowest enrichment compared to the stems and leaves. Such results indicate that submerged plant roots may have a relatively weak role in nitrogen assimilation. The two emergent plants (Phragmites australis and Typha orientalis) showed no differences in δ 15N values among all plant parts, suggesting rapid translocation of nitrogen from roots to other portions. This experiment demonstrates that wetland soil and plant stems and leaves are major sinks for dissolved nitrogen from the surface water and provides valuable insight into nitrogen retention and transport pathways in various wetland plants. [Copyright &y& Elsevier]

Abstract: In this paper, LaPO4 nanorods have been successfully synthesized via a simple water–ethyleneglycol (H2O–EG) mixed-solvothermal route, employing lanthanum nitrate (La(NO3)3·xH2O) as a La3+ ion source and monobasic sodium phosphate (NaH2PO4·2H2O) as a ion source. The as-obtained products were characterized by means of X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS), (high resolution) transmission electron microscopy (HR/TEM), selected area electron diffraction (SAED) and field emission scanning electron microscopy (FESEM). Some factors influencing the formation of LaPO4 nanorods, including the reaction temperature, the volume ratio of water/EG and the original amount of ions, were investigated. Experiments showed that the volume ratio of water/EG and the original amount of ions could markedly affect the morphology of the final product. [Copyright &y& Elsevier]

Abstract: In this paper, we report the successful synthesis of Ni12P5 hollow spheres via a facile hydrothermal route, employing white phosphorus (WP) and nickel nitrate as the reactants in the presence of hexamethylenetetramine (HMT) and polyethylene glycol 10000 (PEG-10000). The phase and morphology of the product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). HMT and surfactant (PEG-10000) played important roles in the formation of Ni12P5 hollow microspheres. Furthermore, research also showed that the as-prepared Ni12P5 hollow spheres could photocatalytically degrade some organic dyes such as Safranine T and Pyronine B under irradiation of 365 nm UV light. [Copyright &y& Elsevier]

Abstract: X-ray diffraction (XRD), temperature-programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS) were employed to investigate the dispersion of copper oxide in CuO/TiO2 samples prepared by one and double-step impregnations and the NO+CO activities of CuO/TiO2 samples were also tested. The results indicate that the dispersion capacity of copper oxide in CuO/TiO2 samples with one-step impregnation and double impregnations are about 0.52 and 0.98mmol/100m2 TiO2, respectively, which should be related to the shielding effect of accompanying NO3 − anions during the impregnations. Therefore, the dispersion capacity of copper oxide on anatase with double impregnations could approach to 1.16mmol/100m2 TiO2, i.e. a value corresponding to the density of vacant sites on the (001) surface of TiO2. The NO+CO activities of CuO/TiO2 samples suggest that dispersed copper oxide species in these catalysts is the mainly active species and the increasing amount of dispersed copper oxide would enhance their activities. It seems to suggest that, for the supported catalysts, double or multiple impregnations would result in better activity than those prepared by one-step impregnation. In addition, the coordination environment of the dispersed copper oxide species existed on the anatase surface has been discussed by the incorporation model [Y. Chen, L.F. Zhang, Catal. Lett. 12 (1992) 51]. [Copyright &y& Elsevier]

In the current paper, the submicron Cu2O hollow spheres composed of small Cu2O nanoparticles of 22 nm in size were successfully prepared via using a multiple emulsion (O/W/O) system as the template. In this system, the interior oil phase was used as the core and exterior oil phase as the dispersion medium to prevent the product from aggregating; the reactants are dissolved in interim water layer. The liquid-droplet of the multiple emulsions plays a template and space-limiting role in addition to preventing the product from aggregation. [Copyright &y& Elsevier]

Human derived composite amnion-chorion membrane (ACM) has been used to facilitate wound healing due to reported anti-inflammatory properties and promotion of cell proliferation. This study aimed to assess the antimicrobial properties of the ACM using novel methods to visualize the antimicrobial efficacy of membranes in situ at different time points. Porcine Pericardium Collagen Membranes (PPCM) served as membrane controls. Circular pieces of the membranes were used in three different assays: insert, agar contact and glass-bottom well assays. Streptococcus gordonii were spotted onto the membranes and the plates were subsequently centrifuged to ensure direct bacterial contact with the membranes in the insert and agar contact assays, thus better mimicking bacterial adherence in the oral cavity. After incubation at 37 °C for 8, 24, and 48 hours, the membranes were dyed with the Live/Dead BacLight Bacterial Viability fluorescence stain and analyzed via confocal microscopy. The results demonstrated that the ACM completely inhibited bacterial growth at all time points, whereas the PPCM did not demonstrate any antimicrobial properties. Within the limits of this study, the ACM showed extremely high antimicrobial efficacy against oral streptococci. In addition, our methods may be useful in assessing antimicrobial properties for biomaterials with minimum diffusion ability, when traditional assessment methods are not applicable. [ABSTRACT FROM AUTHOR]