Activity

This comprehensive review focuses on how HMs pollute the environment and discusses the phytoremediation measures required to reduce the impact of HMs on the environment. We discuss the role of metal transporters in phytoremediation with a focus on Arabidopsis. Then draw insights into the role of genome editing tools in enhancing phytoremediation efficiency. This review is expected to initiate further research to improve phytoremediation by biotechnological approaches to conserve the environment from pollution.The current study investigated the plant growth promoting (PGP) characteristics of multi-metal-tolerant Bacillus cereus and their positive effect on the physiology, biomolecule substance, and phytoremediation ability of Chrysopogon zizanioides in metal-contaminated soil. The test soil sample was detrimentally contaminated by metals including Cd (31 mg kg-1), Zn (7696 mg kg-1), Pb (326 mg kg-1), Mn (2519 mg kg-1) and Cr (302 mg kg-1) that exceeded Indian standards. The multi-metal-tolerant B. cereus seemed to have superb PGP activities including fabrication of hydrogen cyanide, siderophore, Indole Acetic Acid, N2 fixation, as well as P solubilisation. Such multi-metal-tolerant B. cereus attributes can dramatically reduce or decontaminate metals in contaminated soils, and their PGP attributes significantly improve plant growth in contaminated soils. Hence, without (study I) and with (study II) the blending of B. cereus, this strain vastly enhances the growth and phytoremediation potency of C. zizanioides on metal contaminated soil. The results revealed that the physiological data, biomolecule components, and phytoremediation efficiency of C. zizanioides (Cr 7.74, Cd 12.15, Zn 16.72, Pb 11.47, and Mn 14.52 mg g-1) seem to have been greatly effective in study II due to the metal solubilizing and PGP characteristics of B. cereus. This is a one-of-a-kind report on the effect of B. cereus’s multi-metal tolerance and PGP characteristics on the development and phytoextraction effectiveness of C. zizanioides in metal-polluted soil.Ecological and human risks of crude oil associated heavy metals (HMs) in the contaminated agricultural lands were evaluated employing different indices. The indices that were employed includes enrichment factor (EF), contamination factor (Cf),pollution load index (PLI), geo-accumulation index (Igeo), ecological risk index (ERI), contamination degree (Cd), Nemerow’s pollution index (PN), exposure factor (ExF), hazard quotient (HQ) and hazard index (HI). Besides, the adverse effects of crude oil associated HMs on the soil biological properties were also analyzed. The results of Cf and EF were found consistent with each other showing the HMs in the decreasing order of contamination as Mn > Zn > Cr > Ni > Cu. The Igeo and ERI fall in the grade (Igeo>5) and (ERI ≥40) respectively. The results of PLI, Cd, PN and ExF values clearly indicate a high environmental risk of crude oil-associated HMs. The results of the human health risks assessment revealed the maximum level of HMs enters the body via ingestion. There were significant(p less then 0.05) decreases (5.7-15.5 folds) in the activities of cellulase (0.194 ± 0.02-0.998 ± 0.1), phosphatase (0.173 ± 0.3-0.612 ± 1.5), catalase (0.328 ± 0.3-2.036 ± 1.5), urease (0.44 ± 0.3-1.80 ± 1.2), dehydrogenase (0.321 ± 0.2-0.776 ± 0.7),polyphenol oxidase (0.21 ± 0.5-0.89 ± 2.5)and peroxidase (0.13 ± 0.4-0.53 ± 1.03)in crude oil-contaminated soil. The Pearson’s correlation confirmed the significant negative impact of HMs on the soil’s biological properties.A facile hydrothermal route was followed to obtain a ternary composite Ag@AgVO3/rGO/CeVO4 with in-situ deposition of Ag nanoparticles over the AgVO3 nano-belts. The in-situ deposition was promoted and enhanced with the introduction of GO. The as-synthesized composite demonstrated remarkable visible light harvesting efficiency greater than 75% in the visible region. The charge separation and light harvesting properties were achieved through the Z-scheme mechanism mediated through rGO and the electron trapping/Schottky barrier effect from Ag nanoparticles. The reduction in the width of space charge region (∼2.5 times) and simultaneous increase in the density of charge carriers (2.3∗1018) promoted the LED irradiated photocatalytic performance. The decay time of the charge carriers were prolonged in the order of 4.46 s implying the enhancement in the charge separation. The studies were extended to charge trapping and the band structure modelling. The later emphasized on the prominence of Z-scheme mechanism with hole mediated degradation pathway. The LED photocatalysis demonstrated a removal efficiency of 87.20% for MB and 55.51% for phenol with a average AQE of 29.28% (MB) and 13.90% (phenol) for the ternary. The mineralization efficiency determined through TOC analysis was found to be 71.72%, and 66.43% for MB and phenol system respectively.Fine particulate matter (PM2.5) has received worldwide attention due to its threat to public health. In the Sichuan Basin (SCB), PM2.5 is causing heavy health burdens due to its high concentrations and population density. Compared with other heavily polluted areas, less effort has been made to generate a full-coverage PM2.5 dataset of the SCB, in which the detailed PM2.5 spatiotemporal characteristics remain unclear. Considering commonly existing spatiotemporal autocorrelations, the top-of-atmosphere reflectance (TOAR) with a high coverage rate and other auxiliary data were employed to build commonly used random forest (RF) models to generate accurate hourly PM2.5 concentration predictions with a 0.05° × 0.05° spatial resolution in the SCB in 2016. Specifically, with historical concentrations predicted from a spatial RF (S-RF) and observed at stations, an alternative spatiotemporal RF (AST-RF) and spatiotemporal RF (ST-RF) were built in grids with stations (type 1). The predictions from the AST-RF in grids without stations (type 2) and observations in type 1 formed the PM2.5 dataset. The LOOCV R2, RMSE and MAE were 0.94/0.94, 8.71/8.62 μg∕m3 and 5.58/5.57 μg∕m3 in the AST-RF/ST-RF, respectively. Using the produced dataset, spatiotemporal analysis was conducted for a detailed understanding of the spatiotemporal characteristics of PM2.5 in the SCB. The PM2.5 concentrations gradually increased from the edge to the center of the SCB in spatial distribution. Two high-concentration areas centered on Chengdu and Zigong were observed throughout the year, while another high-concentration area centered on Dazhou was only observed in winter. The diurnal variation had double peaks and double valleys in the SCB. The concentrations were high at night and low in daytime, which suggests that characterizing the relationship between PM2.5 and adverse health outcomes by daily means might be inaccurate with most human activities conducted in daytime.Despite increasing attention to the influence of unsteady-state volatile organic compounds (VOCs) on the adsorption of activated carbon, studies in this regard are rare. Therefore, in this study, an investigation into the migration and diffusion of unsteady-state VOCs on activated carbon adsorption beds under reverse ventilation was conducted. Here, reverse clean air was introduced when the activated carbon bed reached the penetration point. 4-DMDR) HCl The influence of reverse ventilation temperature, reverse superficial gas velocity, activated carbon filling height, and different ventilation modes on the adsorption of unsteady toluene by activated carbon were studied. Our experimental results show that when the reverse ventilation temperature increased from 20 °C to 60 °C, the quasi-first-order desorption rate constant increased from 0.00356 min-1 to 0.00807 min-1, an increase in the reverse superficial gas velocity led to a higher rate constant, and at greater reverse superficial gas velocities, the stripping capacity increased. It was observed that the maximum stripping capacity was achieved at a reverse superficial gas velocity of 0.3 m/s. For different activated carbon filling heights, following reverse ventilation, the stripping capacity of a 5 cm and 30 cm activated carbon bed accounted for 41.43% and 65.85% of the original adsorption capacity, respectively. The study concludes that concentration of toluene first increased and then decreased with time under forward ventilation, whereas the concentration gradually decreased under reverse ventilation.Wastewater treatment plants (WWTPs) are key components for the capture of microplastics (MPs) before they are released into natural waterways. Removal efficiencies as high as 99% may be achieved but sub-micron MPs as well as nanoplastics have been overlooked because of analytical limitations. Furthermore, short MP fibres are of concern because of their low capture rate as well as the lack of understanding of their influence on purification system efficiency. This study has investigated the impact of poly(ethylene terephthalate) (PET) short nanofibres on the performance of polyvinylidene fluoride (PVDF) ultrafiltration membranes during cross-flow operation. Model MP fibres with an average length of 10 ± 7 μm and a diameter of 142 ± 40 nm were prepared via a combination of electrospinning and fine cutting using a cryomicrotome. The manufactured MPs were added to both pure and synthetic domestic wastewater at a concentration of 1 mg.L-1 to determine their impact on the performance of PVDF ultrafiltration membranes. The results show that PET fibres attach to the membrane in a disorganised manner with low pore coverage. The water flux was decreased by 8% for MPs in pure water and no noticeable effect in wastewater after 3 days of filtration. Additionally, the nutrient removal efficiency of the membrane was not altered by the presence of PET MPs. These findings show that MP fibres do not significantly influence the early stages of filtration for a standard concentration of MPs in wastewater treatment plant studies.Thermal transformation of carbonized materials to functional activated carbon (AC) is a simplified, economical and eco-friendly strategy, which has great potential in the practical applications of water purification. Herein, a S/Fe codoped activated carbon (S/Fe@AC) with only 0.90 wt% S and 0.76 wt% Fe was creatively fabricated by one synchronous method of physical activation, carbothermal reduction and sulfidation in the solid phase. The formed iron sulfide shell significantly enhances the antioxidation ability of nanoscale zero-valent iron (NZVI, >180 d) and dramatically improves the hydrophobicity of the composite. Meanwhile, the doped thiophenic S in AC enhances the hydrophobicity and increases the specific surface area to 1194.14 m2 g-1. Incorporating with AC in turn greatly strengthens the dispersibility and stability of sulfurized NZVI particles. Compared to NZVI@AC, AC and NZVI, the removal capacity of S/Fe@AC for the representative hydrophobic contaminant-triclosan (TCS) increases to 519.68 mg g-1 by 66.60%, 78.60% and 981.21%, respectively, outperforming most of the previously reported materials. The strong hydrophobic and π-π interactions, and weak hydrogen bonding and electrostatic repulsion are responsible for the excellent removal performance for TCS. More importantly, the improved chemical property (29.38%) of the composite caused by the doped S/Fe has a greater effect on TCS removal compared with the changed physical structure (14.56%). Furthermore, the stable S/Fe@AC shows strong anti-interference capability and exceptional regenerability. These intriguing discoveries provide new insights into the design of advanced and sustainable adsorbing materials for emerging contaminants.