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Thermodynamic data suggest that adsorption of MTX onto NH2-MIL-101 is spontaneous and exothermic, while the adsorption mechanism is governed by electrostatic interactions, π-π stacking interactions, and H-bonding. Regeneration and recyclability of NH2-MIL-101 were also investigated by washing with ethanol to observe its decreased adsorption performance towards MTX. It was slightly decreased after seven adsorption-desorption cycles, indicating excellent regeneration and good structural stability under the chosen experimental conditions.A new self-assembled cellulose (SACS) containing multi-functional amine, carboxyl and hydroxyl groups was successfully obtained through etherification, cross-linking and grafting processes. Then, the adsorption of sulfamethoxazole (SMZ) and Cd(II) onto SACS at pH values of 3, 5.7 and 7.5 was systematically investigated by batch experiments of single, sequential and binary systems, characterization and density functional theory (DFT) calculations. The presence of Cd(II) decreased the adsorption of SMZ because of hydrophilic site competition, while SMZ inversely increased the adsorption of Cd(II), which was attributed to bridging and especially to electrostatic shielding effects; moreover, both the inhibitory and synergistic effects were more obvious in the binary system and at a pH of 7.5. There was a dynamic balance between the inhibitory and synergistic effects that depended on the system, pH value and concentration ratio. DFT results further indicated that SMZ- more easily coordinated with Cd(II) at sulfonyl oxygen and nitrogen sites, and the cationic bridge of Cd(II) with SMZ- mainly occurred in the sequential system. Moreover, a complexation-decomplexation-complexation balance of SMZ- and Cd(II) probably occurred in the binary system.The current study delineated the distribution, (hydro)geochemical behavior and health risk of arsenic (As) in shallow (depth 1.0) risks for groundwater of all areas, with the utmost risk estimated for Chenab floodplain and deep aquifers. Positive saturation index values for Fe oxide mineral phases may suggest their potential role in As mobilization/release in these aquifer environments. This study provides critically-important and baseline knowledge for a widespread groundwater As examination along these three floodplains, which is vital for launching suitable As mitigation and remediation programs to reduce the potential health risk.We introduce a green and facile method to compatibilize hydrophobic polylactide (PLA) with hydrophilic cellulose nanofibers (CNF) by using ionic liquid ([DBNH][OAc]) welding with a cosolvent system (gamma-valerolactone). Such welding affords strong (230 MPa tensile strength), flexible (13% elongation at break), transparent (>90%) and defect-free CNF/PLA films. The films are biodegradable in marine environments (70% degradation in 7 weeks), facilitating the otherwise slow PLA decomposition. Physical, chemical and structural features of the films before and after welding are compared and factored in the trends observed for degradation in seawater. The results point to the possibility of PLA-based films forming a co-continuous system with nanocellulose to achieve an improved performance. The role of film morphology, hydrophobicity, and crystallinity is discussed to add to the prospects for packaging materials that simultaneously display accelerated degradability in marine environments.Biodegradable plastics are becoming increasingly popular due to global concerns about plastic pollution. In this study, the impacts of glitter manufactured of conventional, non-biodegradable polyethylene terephthalate (PET) versus glitter of alternative materials (modified regenerated cellulose (MRC), mica or synthetic mica) on the biodiversity and ecosystem functioning of freshwater, lotic habitats were compared using a semi-natural mesocosm experiment. After 36 days, there was no effect of glitter on overall assemblage structure or diversity indices, however there was a two-fold increase in the abundance of New Zealand mud snails (Potamopyrgus antipodarum) in response to MRC glitter. In addition, the root length of common duckweed (Lemna minor) and phytoplankton biomass (based on chlorophyll content) were significantly reduced by exposure to any type of glitter. On the contrary, the chlorophyll content in the sediment (indicating microphytobenthos biomass) was significantly greater in those exposed to synthetic mica glitter. Organic matter content of sediment did not differ amongst any of the treatments. However initially, on days 8 and 15, NO32- concentration in the control treatment were significantly greater than in all glitter treatments, but this observation disappeared over time. Overall, results indicate that both conventional and alternative glitters can cause ecological impacts in aquatic ecosystems.Construction of heterojunction and nitrogen doping is an effective approach for synthesizing photocatalysts with high quantum yield and efficient electron-hole separation. 2D MXene Ti3C2 has been considered a good carbonaceous nanomaterial for designing heterojunction, while the original surface groups and stacked structure limit the electron-hole separation. Herein, a hybrid of nitrogen-doped Ti3C2 nanosheets and TiO2 nanoparticles (NPs) composed of TiO2 NPs in situ growing on isopropyl amine (iPA) modified Ti3C2 (iN-Ti3C2) was developed for the first time. The novel iN-Ti3C2/TiO2 hybrid exhibited an excellent ultraviolet-light photodegradation of methylene blue (MB), with a degradation rate (0.02642 min-1) significantly higher than that of pure TiO2 NPs, bulk-Ti3C2/TiO2, dimethyl sulfoxide modified Ti3C2/TiO2 hybrid, and hydrazine monohydrate modified Ti3C2/TiO2 hybrid. The formation of heterojunction between iN-Ti3C2 and TiO2 and its role in the photocatalysis were systematically analyzed using various characterization techniques and density functional theory calculation. The iPA modification exfoliated Ti3C2 and doped N on Ti3C2 nanosheets; the in situ grown TiO2 NPs formed efficient heterojunctions with the nanosheets; the N-doping facilitated electron migration in Ti3C2 and inhibited the recombination of photogenerated electron-hole pairs; •OH dominated the photodegradation of MB. selleck chemicals This work provides a new approach of constructing efficient photocatalysts for the treatment of organics-polluted water.