Κυριακή, 30 Ιουνίου 2019

Environmental Science and Pollution Research

Correction to: Ecological risk assessment of metals in sediments and selective plants of Uchalli Wetland Complex (UWC)—a Ramsar site

The correct image of Figure 4 is shown in this paper. The original article has been corrected. Fig. 4: Scree plot of heavy metals in sediments. The graph shown in upper right corner shows the concentration of principle components variables in a loading plot.



Recent advances on advanced oxidation process for sustainable water management


Environment-health link in a context of urban agricultures: studies of oral exposure to pollutants in order promote the human health


Photocatalytic oxidation of toluene and isopropanol by LaFeO 3 /black-TiO 2

Abstract

Large amount of volatile organic compounds (VOCs) are emitted from industrial, mobile, and domestic sources, causing adverse effects on human health and environment. Among VOCs, toluene and isopropanol (IPA) are commonly used as solvent, soldering flux, and spray paint and their emissions need to be reduced. Several VOCs abatement technologies are available to reduce VOC emission and photocatalytic oxidation of VOC is regarded as a viable technique due to its advantage of utilizing solar energy. TiO2 has been investigated for its oxidation capability toward VOCs because of its good photocatalytic activity. However the utilization is limited to UV due to its wider bandgap; furthermore, its fast recombination rate of electron-hole pair reduces the oxidation rate of VOCs. Black-TiO2 and perovskite-type photocatalyst such as LaFeO3 can be applied to enhance photocatalytic activity due to narrower bandgap and longer electron-hole pair lifetime. In this study, black-TiO2 and LaFeO3 are prepared and investigated for their photocatalytic oxidation rates toward toluene and IPA. Results show that toluene removals achieved with black-TiO2 and LaFeO3 are 89% and 98% while IPA removals are 90% and 94%, respectively. Both photocatalysts show better photocatalytic activity than TiO2 and good absorption capability toward visible light.

Graphical abstract



Regulating nitrate excess in lettuce-planted greenhouse soil with available carbon addition through irrigation

Abstract

Nitrate excess is common in greenhouse soils, imposing environmental risks and degrading vegetable quality. In this study, the effectiveness of adding sucrose as available carbon through irrigation to cut nitrate excess in lettuce-planted soil was investigated under impacts of soil texture and irrigation type. In the pot experiment using two loam soils of same origin with different clay to sand ratios (50.2% and 39.8%) and nitrate excess (116.1 and 417.7 mg/kg N), three-time sucrose addition through flood irrigation was more effective in lowering net formation of nitrate-based inorganic N and increasing lettuce yield in the soil with the higher clay to sand ratio, and sucrose addition at 150–450 mg/kg reduced nitrate accumulation and leaching, and nitrate content of lettuce at harvest by 62.5–89.6%, 19.3–36.1%, and 11.4–76.0%, respectively. In the micro-plot field experiment with two-time sucrose addition at 0.6–1.2 g/L through furrow irrigation (42 mm) into two other soils of same origin with different clay to sand ratios (56.9%, 48.4%), nitrate accumulation at 0–30-cm depth at the prone-leaching furrow location at harvest decreased by 30.9–36.0% under the higher clay to sand ratio but increased by about 35% under the lower clay to sand ratio. The nitrate content and yield of ridge-planted lettuce was less affected in either soil. Hence, carbon addition rate, irrigation type, and clay to sand ratio all affected the effect of available carbon addition on nitrate accumulation in vegetable-planted soil, and their joint impacts need better quantification for cutting nitrate excess in soil and improving vegetable quality and even yield.



Effects of vermicomposting on the main chemical properties and bioavailability of Cd/Zn in pure sludge

Abstract

To study the effects of vermicomposting on the chemical properties and bioavailability of Cd/Zn in sludge, earthworms (Eisenia foetida) at different densities were inoculated into pure sludge, and sludge and earthworms were collected regularly to determine the earthworm biomass, the main chemical indexes, the structure of the functional groups, and the Cd/Zn content in the sludge. The results showed that the growth curve of earthworms in pure sludge could be well fitted by the logistic model. Earthworm activity eventually reduced the total organic carbon (TOC), fulvic acid (FA), and C/N ratio and increased the electrical conductivity (EC), total nitrogen (TN), humic acid (HA), and HA/FA ratio in the sludge. TOC, TN, and pH inhibited the bioavailability of Cd/Zn, while HA and EC promoted the bioavailability of Cd/Zn. Earthworm activity ultimately increased the content of Cd/Zn in the sludge. The bioavailability of Cd/Zn was reduced during the rapid growth period of the earthworms but increased during the stable growth period of the earthworms. A suitable vermicomposting time should be determined to ensure the activation or passivation of Cd/Zn.



Metal content in the liver, kidney, and feathers of Northern gannets, Morus bassanus , sampled on the Spanish coast

Abstract

The value of birds as bioindicators for monitoring the environmental inorganic elements has been globally recognized. In this context, due to its well-known ecology and population stability, the Northern gannet (Morus bassanus) could be particularly useful. Dead Northern gannets (n = 30) were collected and samples from the liver, kidney, and feathers were taken, dried, mineralized, and finally analyzed via ICP-MS. Metals and metalloids, namely As, Cd, Hg, Pb, and Zn, associated with environmental pollution and toxicity on living organisms, were evaluated. The mean highest concentrations of As, Hg, and Zn were found in the liver (0.916, 7.026, and 89.81 mg/kg dry weight, respectively). For Cd, the kidney showed the highest mean concentration (17.51 mg/kg dry weight), whereas for Pb, this value corresponded to the feathers (0.399 mg/kg dry weight). Significant differences were found between the age classes in terms of contaminant concentrations, with the adults exhibiting higher metal levels. This difference was significantly relevant for Pb and Hg, where the effect of age was observed for all the considered tissues. When considering the effect of gender, no significant differences were observed, in agreement with similar studies performed in other geographical regions. Finally, positive correlations between the concentrations of Hg and Pb in the feathers and in the liver (r = 0.688, p < 0.001 and r = 0.566, p < 0.001, respectively) were observed, as well as between the feather and kidney concentrations (r= 0.685, p < 0.001) indicating the possibility to use feathers, a non-invasive biomonitoring tissue, for better understanding Hg and Pb exposure in seabirds.



Evaluation of the association between urinary cadmium levels below threshold limits and the risk of diabetes mellitus: a dose-response meta-analysis

Abstract

As cadmium levels are increasing in the environment, the adverse effects of cadmium exposure specifically associated with chronic diseases are receiving increasing attention. Several population–based studies have been conducted on the association between cadmium and diabetes mellitus (DM) but have reported controversial results. Here, we aimed to evaluate the association between cadmium exposure and DM. In this meta-analysis, a random effects model was used because there was evidence of heterogeneity among studies. A dose-response relationship was assessed through a restricted cubic spline model with three knots. The results showed a positive association between cadmium levels in the body and DM (OR = 1.27; 95% CI, 1.07–1.52). The cadmium levels in the body were defined on the basis of combined urinary and blood cadmium. Subgroup analysis further indicated a positive association between urinary cadmium levels and DM (OR = 1.31; 95% CI, 1.02–1.69). The dose-response analysis results showed a positive association between levels of urinary cadmium above 2.43 μg/g creatinine and DM, and the risk of DM increased by 16% for each l μg/g creatinine increase in urinary cadmium levels. The results from our meta-analysis indicate that cadmium levels in the body are positively associated with DM, and urinary cadmium levels above 2.43 μg/g creatinine are associated with an increased risk of DM.



Performance of desulfurization ash for the preparation of grouting fire prevention material

Abstract

The accumulation of desulfurization ash from coal-fired power plants can lead to serious waste of land resources and environmental safety problems. This work presents an experimental study on the feasibility of recycling original desulfurization ash as the main raw materials, and a new green grouting material was prepared. The results indicate that a desulfurization ash–based grouting fire prevention material which was prepared according to the following ingredient design (a water-to-solid ratio of 1.0:1 and a hydroxyethyl cellulose content of 0.09% desulfurization ash, 12% quicklime, 0.6% Na2SO4, and 0.05% triethanolamine, 80 °C curing). The slurry's viscosity meets requirements, and its suspension, liquidity, and consolidation strength are better than those of clay under the same conditions. In addition, the grouting material's inhibitor ratio is increased with temperature increase, which means it has good flame retardancy. Environmental performance tests concluded that when desulfurization ash as-recycled admixture is used for the preparation of grouting fire prevention material, from the technique point of view, the environmental safety of them is very good.



Adsorption mechanism of Pb 2+ ions by Fe 3 O 4 , SnO 2 , and TiO 2 nanoparticles

Abstract

Nanosized sorbents for the removal of heavy metal ions are preferred due to high surface area, smaller size, and enhanced reactivity during adsorbate/adsorbent interactions. In the present study, Fe3O4, SnO2, and TiO2nanoparticles were prepared by microemulsion-assisted precipitation method. The particles were characterized by BET surface area, X-rays diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, transmittance electron microscopy (TEM), and X-ray photoelectron (XPS) spectroscopy. The respective particle sizes calculated from TEM were 7 nm (± 2), 10 nm (± 2), and 20 nm (± 3) for Fe3O4, SnO2, and TiO2. The adsorbents were employed for the adsorption of Pb2+ ions from the aqueous solutions. The respective maximum adsorption capacity for Fe3O4, SnO2, and TiO2 nanoparticles was 53.33, 47.21, and 65.65 mg/g at 313 K. Based on the exchange reaction taking place on the surfaces of Fe3O4, SnO2, and TiO2, it is concluded that Pb2+ ions are adsorbed in hydrated form. The X-ray photoelectron spectroscopy (XPS) studies also support the exchange mechanism and confirmed the presence of elements like Fe, Sn, Ti, Pb, and O and their oxidation states. Both Langmuir and Freundlich models in non-linear form were applied, however, based on RL values, the Langmuir model fits well to the sorption data. Moreover, adsorption parameters were also determined by using non-linear form of the Langmuir model along with statistical approaches to remove error. The qm and Kb values confirm better adsorption capacity and binding strength for Pb2+ ions as compared to the values reported in the literature.



Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

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