Indigenous mixotrophic aerobic denitrifiers stimulated by oxygen micro/nanobubble-loaded microporous biochar.

The prevalence of hypoxia in surface sediment inhibits the growth of aerobic denitrifiers in natural waters. A novel oxygen micro/nanobubble-loaded microporous biochar (OMB) was developed to activate indigenous aerobic denitrifiers in this study. The results indicate a thin-layer OMB capping mitigates hypoxia effectively.

Controlling internal nutrients loading at low temperature using oxygen-loading zeolite and submerged macrophytes enhances environmental resilience to subsequent high temperature.

Nutrients releasing from anoxic sediment can be enhanced in summer because the dissolved oxygen (DO) consumption, nitrogen (N) and phosphorus (P) migration are susceptible to temperature. Herein, we proposed a method to hinder the aquatic environmental deterioration in warm seasons through consecutive application of oxygen- and lanthanum-modified zeolite (LOZ) and submerged macrophytes (V. natans) at low temperature scenario (5 °C, with depleted DO in water), and the effect was examined with drastic increasing the ambient temperature to 30 °C.

Potential disintegration and transport of biochar in the soil-water environment: A case study towards purple soil.

Biochar has been widely applied in soil and water. However, the fate and transport of biochar are not yet fully understood. Here, biochar's disintegration, transport, and the effect of temperature on biochar transport in soil (purple soil)-water systems were investigated.

Fate of dissolved inorganic nitrogen in turbulent rivers: The critical role of dissolved oxygen levels.

Dissolved inorganic nitrogen (DIN) is considered the main factor that induces eutrophication in water, and is readily influenced by hydrodynamic activities. In this study, a 4-year field investigation of nitrogen dynamics in a turbulent river was conducted, and a laboratory study was performed in the approximately homogeneous turbulence simulation system to investigate potential mechanisms involved in DIN transformation under turbulence. The field investigation revealed that, contrary to NO dynamics, the NH concentrations in water were lower in flood seasons than in drought seasons.

Cytotoxic effects of polystyrene nanoplastics with different surface functionalization on human HepG2 cells.

Nanoplastics in the environment lead to the human exposure to these particles. However, the consequences of this exposure are not yet fully understood. Here, the cytotoxicity of polystyrene nanoparticles (PS-NPs) with a uniform size (50 nm) but distinct surface functionalization (pristine polystyrene, PS; carboxy and amino functionalized, PS-COOH and PS-NH, respectively), and at an exposure dosage of 10, 50 and 100 μg/mL, were assessed in the human hepatocellular carcinoma (HepG2) cell line.

Quantification of Oxygen Nanobubbles in Particulate Matters and Potential Applications in Remediation of Anaerobic Environment.

Interfacial nanobubbles can exist on various hydrophobic and hydrophilic material interfaces. There are diverse applications for oxygen nanobubbles, which are closely related to their content and long-term stability. However, it remains challenging to determine the amount of nanobubbles loaded in a porous material.

Microwave-Induced Interfacial Nanobubbles.

A new method for generating nanobubbles via microwave irradiation was verified and quantified. AFM measurement showed that nanobubbles with diameters ranging from 200 to 600 nm were generated at a water-HOPG surface by applying microwave radiation to aqueous solutions with 9.0-30.