Search

The existence of toxic and carcinogenic pentavalent antimony in water is a great safety problem. In order to remove antimony(V) from water, the purpose of this study was to prepare a novel graphene nano iron zinc (rGO/NZV-FeZn) photocatalyst via hydrothermal method followed by ultrasonication. Herein, weakly magnetic nano-Fe–Zn materials (NZV-FeZn, GACSP/NZV-FeZn, and rGO/NZV-FeZn) capable of rapid and efficient Sb(V) adsorption from water were prepared and characterised. In particular, rGO/NZV-FeZn was shown to comprise franklinite, Fe0, and graphite. Adsorption data were fitted by a quasi-second-order kinetic equation and Langmuir model, revealing that among these materials, NZV-FeZn exhibited the best Sb removal performance (543.9 mgSb gNZV-FeZn−1, R2 = 0.951). In a practical decontamination test, Sb removal efficiency of 99.38% was obtained for a reaction column filled with 3.5 g of rGO/NZV-FeZn. Column regenerability was tested at an initial concentration of 0.8111 mgSb L−1, and the treated water obtained after five consecutive runs complied with the GB5749-2006 requirement for Sb. rGO/NZV-FeZn was suggested to remove Sb(V) through adsorption-photocatalytic reduction and flocculation sedimentation mechanisms and, in view of its high cost performance, stability, and upscalable synthesis, was concluded to hold great promise for source water and wastewater treatment. [ABSTRACT FROM AUTHOR]

Norovirus diarrhea is a great threat to public health worldwide. To characterize the prevalence of circulating noroviruses associated with sporadic gastroenteritis cases in Guangzhou, 215 stool specimens were collected during two consecutive cold seasons in 2013-2015. Noroviruses were detected in 25 (11.63 %) samples, and GII.4 (6/9) and GII.17 (10/16) were identified as the most predominant variants of each of those seasons. The remaining strains belonged to the genotypes GII.P12/GII.3, GII.2, and GI.Pb/GI.6. The phylogenetic relationships of the GII.17 strains were analyzed based on their capsid protein sequences. This study suggests a significant shift of predominant variants associated with sporadic gastroenteritis in Guangzhou. [ABSTRACT FROM AUTHOR]

In this study, nanoiron active carbon composites (NZVI/GAC) were used to remove chromium ions from raw water. The composites were synthesized from a novel formula of biological activated carbon and characterized by various techniques. The adsorption test data were fit by a pseudo-second-order kinetic model and Langmuir model. The qe and R2 values were 187 mg Cr/g and 0.9960, respectively, with 0.2 g/L NZVI/GAC at an initial concentration of 118 mg/L Cr according to the Langmuir isotherm model. Moreover, a Cr6+ detoxification reactor was constructed with the magnetic iron composite. The results indicated that the synthesized magnetic iron composite was a significant adsorbent for Cr6+ removal from aqueous solutions. The detoxification reactor was able to remove Cr6+ from raw water at an initial concentration of 26.5 mg/L within a short time period (3–5 min), with a removal efficiency of up to 99.90% and a treatment capacity of 45.0 mg Cr6+/g of adsorbent; the Cr6+ concentrations in the outflow met the GB5749–2006 requirements for drinking water. A synergistic effect between NZVI/GAC and a suspension of the bacterium Shewanella oneidensis MR-1 was found, showing that this bacterium can be used as a regeneration agent for iron-depleted activated carbon materials. [ABSTRACT FROM AUTHOR]