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Advanced oxidation processes based on persulfate activation can produce strong reactive oxygen species, which can effectively degrade a variety of organic pollutants. However, finding cost-effective activation methods and materials have become the key in the research process of this oxidation technology. With the discovery of the catalytic activity of biochar, the application of carbonaceous materials in persulfate activation has recently emerged. In this study, recyclable magnetic biochar was prepared from dewatered piggery sludge, and was used to activate peroxymonosulfate to degrade antibiotic tetracycline. Results showed that the catalytic activity of magnetic biochar was stronger than that of unmagnetized sludge biochar, and magnetic biochar showed better separation and sustainability in recovery and reuse. Neutral pH condition was also favorable for biochar and magnetic biochar to activate peroxymonosulfate. Peroxymonosulfate activation using magnetic biochar is an economical, efficient and environmentally friendly method for organic pollutants degradation. [Display omitted] • The catalyst with high efficiency and low cost was prepared by Fe 3 O 4 modification. • Magnetic biochar showed a high activity for the activation of peroxymonosulfate. • Reveal the mechanism of tetracycline degradation catalyzed by magnetic biochar. • Valuable utilization of agricultural waste piggery sludge was proposed. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization is a novel technology for dewatering of sewage sludge. Layered double hydroxides (LDHs) are a widely used functional material, which can be prepared by hydrothermal method. In this study, we proposed a new process combining hydrothermal carbonization of sludge and in-situ preparation of LDHs. The addition of Mg and Al salts (as LDHs precursor) to the slurry before hydrothermal treatment can act as a sludge conditioner to effectively accelerate the sludge sedimentation. The obtained products hydrochar/LDHs (HL) composites with various mass ratios were analyzed by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that the well-crystallized LDHs slice is thinner after combining with hydrochar. The HL products can be used as a highly effective adsorbent for removal of Pb2+ from water. The adsorption experiment results showed that the adsorption behavior of Pb2+ onto HL composites can be well expressed by a pseudo-second-order kinetic model and Langmuir isotherm with the maximum adsorption capacity of 62.441 mg/g. Ionic strength had no significant effect on the adsorption capacity. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectra indicated that the adsorption mechanisms of Pb2+ by HL composites mainly included electrostatic interaction and surface coprecipitation. Therefore, this is a cost-effective method to obtain a high efficiency adsorbent. • Hydrothermal treatment of sludge and in-situ preparing layered double hydroxides. • Layered double hydroxides precursor solution can act as sludge conditioner. • The composites has a higher adsorption capacity of Pb(II) than other adsorbents. • The microstructure of the composites and their adsorption mechanism are deciphered. • This is a cost-effective method to obtain a high efficiency adsorbent. [ABSTRACT FROM AUTHOR]

Aberrant expression of microRNAs (miRNAs) has been widely recognized to play critical roles in the pathogenic processes of colon cancer. However, the expression and functions of miR-3653 in colon cancer remain uncovered. This study revealed for the first time that miR-3653 expression was significantly decreased in colon cancer tissues and cell lines. MiR-3653 overexpression led to decreased migration and invasion of HCT116 cells while miR-3653 knockdown resulted in opposite influence of the metastatic behaviors of HT29 cells. qRT-PCR and western blot demonstrated that miR-3653 suppressed the epithelial-mesenchymal transition (EMT) of colon cancer cells using both gain- and loss- of function assay. Mechanically, miR-3653 was found to interact with the 3′-UTR of Zeb2 through the complementary sequences and inhibited the expression of Zeb2 in colon cancer cells. Rescue experiments demonstrated that the inhibitory effect of miR-3653 overexpression on cell metastasis and EMT was abrogated by forced expression of Zeb2. This study demonstrates that miR-3653 suppresses the metastasis and EMT of colon cells by targeting Zeb2, and serves as a promising biomarker and therapeutic target in colon cancer. [ABSTRACT FROM AUTHOR]

Nanoplastics (NPs) nano-scale effects and have strong mobility, posing potential risks to ecosystems and human health. Therefore, it is of great significance to study the interactions of minerals and NPs in water to understand the migration, transformation, and fate of NPs in the environment. This study investigated the flocculation of NPs on layered double hydroxides (LDHs) in water via heteroaggregation under various conditions such as different Mg/Al ratios of LDHs, calcination temperatures, coexisting ions, solution pH, and contact time. We found that the overall reaction achieved high efficiency that almost surpassed 70% and varied with solution pH. The highest flocculation performance (85.87%) was achieved at a Mg:Al ratio of 3:1, followed by 4:1 and 2:1. Moreover, the highest removal rate (80.85%) of NPs on cLDHs was achieved at calcination temperature of 300 °C. The heteroaggregation mechanism, bonding type, and interface reaction of the NPs–LDHs system were analyzed using the Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, spectroscopy, and microscopy. At short separation distance within 5 nm, the total interaction energy was governed by electrostatic repulsion. However, at longer distance, the interparticle forces became dominated by van der Waals and electrostatic attractions, leading to attachment of two types of particles. The NPs could be removed by attachment onto the surface of LDHs without forming other functional groups. However, the calcined LDHs and those prepared by hydrothermal reactions showed different attachment morphologies under scanning electron microscopy, which revealed the mechanisms of surface attachment and encased precipitation. These results provided new insights and theoretical support for controlling NPs pollution in surface water, which could reduce the risks of NPs to ecosystems and human health. [Display omitted] • The settling efficiency of NPs with Mg/Al LDHs surpassed 80%. • NPs tended to attach to the surface of Mg/Al LDHs and settled down. • The maximum removal rate was achieved for 10 mg/L NPs on 0.5 g/L Mg/Al LDHs. • Electrostatic and van der Waals forces are the main interaction mechanisms. • This study provided a new insight for controlling NPs pollution in surface water. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Adsorption functional groups were successfully grafted on cellulose. • Adsorption capacity on the cellulose was markedly increased by modification. • pH has little effect on the zeta potential of cellulose after modification. • Adsorption mechanisms of Cu(II) include complexation & electrostatic attraction. Abstract In order to synthesize adsorbent that can effectively absorb heavy metals in a simple and economical way, this study described the fabrication of adsorbents based on cellulose acetate (CA). CA modified first by polyethyleneimine grafting (CAP) and then by ethylenediamine (CAPE) for enhancing Cu(II) and Pb(II) removal from water. The physico-chemical properties of the modified celluloses were analyzed. It was found that the adsorption functional groups (amino groups) were successfully grafted on cellulose and CAP converted from semi-crystalline to cellulose II after enhancement of ethylenediamine (EDA). Adsorption isotherm results showed that the Cu(II) and Pb(II) removal efficiency by CAPE was significantly higher than that by CAP, and CAP showed a higher adsorption capacity of Cu(II) and Pb(II) than CA, of which the adsorption isotherm modeled with Langmuir isotherms well. The adsorption capacity can significantly be affected by ionic strength and humic acid. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) results demonstrated the complexation between amino groups and Cu(II)/Pb(II) played an important role for adsorption onto CAPE. [ABSTRACT FROM AUTHOR]