Environmental Science: Nano最新文献

Nano-titanium dioxide (nano-TiO₂) is a ubiquitous contaminant in the marine environment that accumulates in sediments and biological tissues. Coupled with global warming, these challenges can enhance the deleterious properties of nano-TiO₂, leading to compounded pollution effects on marine life and ecosystems. This study investigated the effects of nano-TiO₂ and increased temperatures on the Japanese swimming crab's gut microbiota and digestive system, Charybdis japonica, through different scenarios. We employed three exposure scenarios: direct exposure (DE) of the crabs to warming and nano-TiO₂, indirect exposure (IE) through consumption of mussels Mytilus coruscus subjected to the same conditions, and combined exposure (CE), where crabs were directly exposed to warming and nano-TiO₂ while consuming affected mussels. Additionally, a control group was established, comprising Japanese crab C. japonica and thick-shelled mussel M. coruscus that were reared under standard temperature (22 °C, the average annual temperature in the region where the mussels and crabs were sampled) and 0 mg L⁻¹ nano-TiO₂ concentration conditions. The findings indicated that warming and nano-TiO₂ disrupted the crabs' ATP production, digestive responses, and body chemical composition, leading to intestinal flora dysfunction. Notably, nano-TiO₂ exerted a stronger impact on the crabs' digestive enzymes and intestinal flora than warming alone; however, the concurrent presence of warming and nano-TiO₂, especially under the direct exposure (DE) conditions, generally exacerbated the negative effects of nano-TiO₂. This research provides valuable insights into the implications of nano-TiO₂ and elevated temperature on the digestive responses of marine crabs.

The essential nutrients for healthy crop growth may affect the nanotechnology-based remediation of agricultural soils contaminated with cadmium (Cd). However, this hypothesis has not been thoroughly explored. This study investigated the Cd biotransformation and accumulation in wheat growing under a hydroponic system regulated by various nitrogen (N) and phosphate (P) fertilizers, after treatment with green-synthesized nano-zero-valent iron supported by diatomite (GnZVI@DE) composites. We found that the presence of urea–N and P with GnZVI@DE respectively inhibited Cd accumulation by 67.7% and 26.2% in wheat seedlings, alleviating further oxidative damage to wheat. This was because urea–N promoted the dispersion of GnZVI@DE particles that originated from increased steric hindrance. P induced the polyphosphate production on tea polyphenols covering GnZVI@DE, increasing Cd(II) adsorption and precipitation by 47.9% for lesser uptake by root surfaces. Conversely, nitrate-N and ammonium-N promoted Cd accumulation in wheat shoots by 86.0% and 26.3%. This was mainly attributed to reduced Cd immobilization by nanocomposites due to GnZVI@DE oxidation by nitrate and competitive adsorption by ammonium. Our study provides insights for developing a sustainable strategy for the remediation of Cd-contaminated soils and the healthy growth of wheat achieved by the synergistic force of nano-amendments combined with urea and phosphate fertilizers.

Currently, the strategy of metal loading is expected to promote the nonradical catalytic activity of transition metal spinel oxide catalysts in peroxymonosulfate (PMS) systems, but the connection between the mechanism of degradation performance improvement and metal–support interaction (MSI) remains unclear. Herein, a novel CoFe₂O₄ loaded sepiolite composite (10-CFS) was prepared for PMS activation to degrade ciprofloxacin (CIP). 10-CFS exhibited outstanding PMS activation ability, and 98.7% of CIP was degraded within 30 min, which was significantly higher than that of the physical mixture of sepiolite and CoFe₂O₄ (59.8%). A series of experiments demonstrated that the presence of Co(IV)O caused the better degradation performance of 10-CFS. Notably, theoretical calculations signified that MSI not only promoted the coupled electron–proton transfer (CEPT) process and thus changed the formation pathway of Co(IV)O, but also facilitated PMS adsorption on 10-CFS and lowered the energy barrier for Co(IV)O generation. In summary, this study illustrates deeply the mechanism of catalytic performance improvement after metal loading by focusing on the MSI and bridges the gap in understanding the MSI and degradation performance.

Soil salinity threatens global food security, crippling agricultural productivity and demanding innovative solutions. On the other hand, mitigating salt stress using additives in the soil not only addresses the widespread issue of soil salinity but also opens the way for using ocean water in the cultivation process. This promising solution holds the potential to revolutionize agricultural practices and usher in a new era of sustainable and resilient food production. In this study, we explore the potential of graphene oxide (GO) as an additive to alleviate soil salinity. In a typical case study, we cultivated tomato plants in water containing 100 mM NaCl solution, with and without the presence of GO in the soil. These conditions were then compared against a control group. This study implies the feasibility of plantations in salty soil and the utilization of saltwater for the cultivation process.