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Marine sediment is considered a vast sink for organic pollutants including polycyclic aromatic hydrocarbons (PAHs). However, little is known about the relationship between subcritical PAH allocation and benthic microbial patterns. Thus, we carried out a field investigation at the abandoned Yellow River Delta (AYRD) to deepen the understanding of PAHs' horizontal distribution and ecological roles on the continental shelf. The PAH level in the AYRD is relatively low and distance-independent, indicating it resulted from long-term, chronic, anthropogenic input. The combined application of diagnostic molecular ratios reported inconsistent PAH sources, which might be due to the low PAH concentrations and the complexity of contributing sources. Positive Matrix Factorization provided a more robust source classification and identified three main PAH sources-coal combustion and vehicle emissions, petrogenic process, and fossil fuels. The benthic microbiome did not show a significant response to PAHs in terms of microbial assemblage or alpha-diversity. However, Operational Taxonomic Units in some specific phyla, like Thaumarchaeota, Proteobacteria, Acidobacteria, and Chytridiomycota, correlated with the PAH source indicators, supporting the notion that PAH source indicators can act as a novel environmental indicator for microbial adaption. What's more, Microbial Ecological Networks show more connection at sites identified as biomass combustion by both Fluoranthene/(Fluoranthene + Pyrene) and Indeno(1,2,3-cd)pyrene/(Indeno(1,2,3-cd)pyrene + Benzo(ghi)perylene) compared to the ones identified as biomass combustion by Fluoranthene/(Fluoranthene + Pyrene) and petroleum combustion by Indeno(1,2,3-cd)pyrene/(Indeno(1,2,3-cd)pyrene + Benzo(ghi)perylene). Herein, we demonstrate that the PAHs' source indicator can serve as a novel indicator of the interactions between microorganisms, and thus, should be applied to the sustainable management effort in the offshore area.

Terrestrial fungi, especially arbuscular mycorrhizal (AM) fungi, enhance heavy metal sequestration and promote ecosystem restoration. However, their ecological functions were historically overlooked in discussions regarding water quality. As an AM fungi-derived stable soil protein fraction, glomalin-related soil protein (GRSP) may provide insights into the ecological functions of AM fungi associated with water quality in coastal ecosystems. Here, we first assessed the metal-loading dynamics and ecological functions of GRSP transported into aquatic ecosystems, characterized the composition characteristics, and revealed the mechanisms underlying Cu and Cd sequestration. Combining in situ sampling and in vitro cultures, we found that the composition characteristics of GRSP were significantly affected by the element and mineral composition of sediments. In situ, GRSP-bound Cu and Cd contributed 18.91–22.03% of the total Cu and 2.27–6.37% of the total Cd. Functional group ligands and ion exchange were the principal mechanisms of Cu binding by GRSP, while Cd binding was dominated by functional group ligands. During the in vitro experiment, GRSP sequestered large amounts of Cu and Cd and formed stable complexes, while further dialysis only released 25.74 ± 3.85% and 33.53 ± 3.62% of GRSP-bound Cu and Cd, respectively.

To better understand the uptake, biotransformation and physiological response to tetrabromobisphenol A (TBBPA) in mangrove plants, a short term 14-day hydroponic assay with two mangrove species, Avicennia marina (A. marina) and Kandelia obovata (K. obovata), was conducted. Results showed that two mangrove species could uptake, translocate and accumulate TBBPA from solution. The hydroxylation and debromination metabolites of TBBPA, including OH-TBBPA, TriBBPA, MonoBBPA, and BPA, were found in both mangroves for the first time. The high-level TBBPA suppressed the growth and increased malondialdehyde (MDA) content of K. obovata, did not pose any negative affect on A. marina. The activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) of K. obovata significantly increased in the 7th day, whereas, SOD and POD activities at high-levels of TBBPA became comparable to the control in the 14th day. Contrastingly, the antioxidant enzymes activities of A. marina were positively stimulated by TBBPA during the 14-day of observation, indicating that A. marina was more tolerant of TBBPA.

Mesoporous ZnO/TiO 2 hollow microspheres have been successfully synthesized by a facile one-step hydrothermal route without any template. The effect of reactants, temperature and hydrothermal time on the morphology and photocatalytic degradation activity has been investigated in details. The hollow microspheres with average diameter of 0.5–2 μm showed time-dependent growth process and consisted of nanoparticles with a diameter of 10–20 nm. The photocatalytic activity of ZnO/TiO 2 hollow microspheres was evaluated via the photocatalytic degradation of methyl orange (MO). Compared with the pristine TiO 2 hollow microspheres or ZnO nanosheets, the ZnO/TiO 2 hollow microspheres produced significantly positive effect on the band-gap energy shift (from 3.16 eV (TiO 2 ) to 2.80 eV (ZnO/TiO 2 )) and photocatalytic degradation (with a high apparent reaction rate of 10.19 × 10 −2 min −1 ) probably owing to the hybrid hollow microsphere morphology and their synergistic catalytic effect.

Mg2Ni alloy prepared by vacuum induction melting is rapidly quenched in the presence of an external magnetic field. The effects of magnetic field on the microstructure and electrochemical hydrogen storage behavior of Mg2Ni alloy are well investigated for the first time. X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) studies show that the applied magnetic field results in a preferred orientation growth during the rapid solidification of alloy melt, which induces the generation of columnar crystals. Meanwhile, decreased grain size and increased internal strain are noted for this alloy, as well as the eliminated composition segregation. It is found on the charge–discharge experiments that the as-prepared alloy displays an increased capacity and improved cycle stability compared to the alloys without magnetic field treatment. The potentiodynamic polarization results indicate that the Mg2Ni alloy exhibits relatively high corrosion resistance against the alkaline solution. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) results demonstrate enhanced electrochemical kinetics for the treated Mg2Ni alloy, consistent with the enhanced electrochemical properties.