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Polyamide (PA) and bisphenol A (BPA) are selected as typical microplastic and endocrine-disrupting chemicals in this study. The adsorption of BPA on the surface of PA and the effect of PA on the transport behavior of BPA in groundwater are systematically investigated using a combination of batch experiments, column experiments and numerical models. The results of scanning electron microscope (SEM) and Fourier transform infrared spectra (FTIR) show that the surface of PA particles is changed significantly after adsorption of BPA. The isothermal adsorption process of BPA can be simulated by the Langmuir model and the Freundlich model. Kinetic adsorption, on the other hand, can be fitted by a quasi-first-order adsorption model, and the adsorption results indicate that the maximum adsorption of BPA on PA reaches 13 mg·g−1. The results of the column experiments suggest that the mass recovery rate of BPA decreases with PA content, and increases with flow velocity, while initial concentration has no apparent influence on BPA transport. In addition, due to the hydrolysis of BPA, the mass recovery rate of BPA does not change with pH under conditions of pH < 10.2 and increases substantially to 94% when pH > 10.2. Moreover, Ca2+ has a significant inhibitory effect on the transport of BPA, while Na+ has no apparent influence on the transport of BPA. The transport process of BPA in porous media is simulated using a single-point kinetic model, and the fitted mathematical relationships for the variation of kinetic parameters with environmental factors are obtained by regression analysis. [ABSTRACT FROM AUTHOR]

The Machangqing complex is composed of early syenitic-monzonitic porphyry and late granite-porphyry. Geochemically, they are similar in major and trace element characteristics, and are characterized by relatively low TiO2 (< 0.5) and P2O5 (< 0.4) and high alkali contents (K2O + Na2O > 8%), with K2O/Na2O > l, the absence of significant Eu anomaly and pronounced negative anomalies in Nb, Ta, Ti, and enrichment in large-ion lithophile elements and light rare-earth elements. Zircon U-Th-Pb ELA-ICP-MS age determination of the Machangqing complex has revealed two discrete igneous events. The syenitic-monzonitic porphyry has an age of 35.6 ± 3 Ma, MSWD = 2.80; the granite-porphyry, 35.0 ± 0.2 Ma, MSWD = 2.91. The lifespan of magmatic activities of the Machangqing complex associated with Cu + Mo mineralization is about 0.6 Ma. The late-stage ore-bearing granite-porphyry has higher Ce4+/Ce3+ ratios (264) than the early-stage barren syenitic-monzonitic porphyry (102). The increase of zircon Ce4+/Ce4+ ratios from the early- to late-stage porphyries indicates that the oxidation state of the magmas associated with copper mineralization increases with time. [ABSTRACT FROM AUTHOR]

Abstract: Nitrogen and cerium codoped TiO2 photocatalysts were prepared by a modified sol–gel process with doping precursors of cerium nitrate and urea, and characterized by X-ray diffraction (XRD), thermogravimetry–differential scanning calorimetry (TG–DSC), X-ray photoelectron spectra (XPS) and ultraviolet–visible light diffuse reflectance spectra (UV–vis DRS). Results indicate that anatase TiO2 is the dominant crystalline type in as-prepared samples, and CeO2 crystallites appear as the doping ratio of Ce/Ti reaches to 3.0at%. The TiO2 starts to transform from amorphous phase to anatase at 987.1K during calcination, according to the TG–DSC curves. The XPS show that three major metal ions of Ce3+, Ce4+, Ti4+ and one minor metal ion of Ti3+ coexist on the surface. The codoped TiO2 exhibits significant absorption within the range of 400–500nm compared to the non-doped and only nitrogen-doped TiO2. The enhanced photocatalytic activity of the codoped TiO2 is demonstrated through degradation of methyl orange under visible light irradiation. [Copyright &y& Elsevier]

Due to the extensive use of plastic products and unreasonable disposal, nanoplastics contamination has become one of the important environmental problems that mankind must face. The composition and structure of porous media can determine the complexity and diversity of the transport behavior of nanoplastics. In this study, the influence of diatomite (DIA) on the nanoplastics transport in porous media is investigated by column experiments combined with XDLVO interaction energy and transport model. Results suggest that the recovery rates of unmodified polystyrene nanoparticles (PSNPs) and carboxyl-modified polystyrene nanoparticles (PSNPs-COOH) in the porous media containing DIA decreases compared with that in the pure quartz sand (QS), and the BTCs showed a "blocking" pattern. The presence of DIA inhibits the transport of both PSNPs and PSNPs-COOH, but the inhibition is not significant. This may be because the presence of DIA provides more favorable deposition sites for PSNPs and PSNPs-COOH to some extent. However, since DIA itself carries a certain negative charge, this can only play a role in compressing the double electric layer for PSNPs and PSNPs-COOH with the same negative charge, and cannot destabilize them. The migration capacity of PSNPs and PSNPs-COOH is strongest in the DIA-QS porous media at pH = 7, and is weak at pH = 9 and pH = 5. The inhibition of migration at pH = 9 can be attributed to the dissolution of the DIA surface under alkaline conditions and the formation of pore and defect structures, which provide more deposition sites for PSNPs and PSNPs-COOH. The presence of humic acid (HA) leads to an increase in the mobility of PSNPs and PSNPs-COOH, and the mobility is enhanced with HA concentration. The mobility of PSNPs and PSNPs-COOH in DIA-QS decreases with ionic valence and ionic strength, and PSNPs-COOH is more significantly inhibited compared to PSNPs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Herein we report the electrochemical synthesis of porous Pr(OH)(3) nanobelt arrays (NBAs), nanowire arrays (NWAs), nanowire bundles (NWBs), and nanowires (NWs) and their applications as dye absorbents in water treatment. These Pr(OH)(3) nanostructures exhibit high efficient and selective adsorption of the dyes with amine (-NH(2)) functional groups such as Congo red, reactive yellow, and reactive blue. The high efficiency and selectivity is attributed to the large effective surface area of the porous structure, plentiful hydroxyl groups, and basic sites on the Pr(OH)(3) surface. Furthermore, the toxicity studies of these porous Pr(OH)(3) nanostructure show a negligible effect on seed germination, indicating that they hold great potential as environmentally friendly absorbents in water treatment.

Various genotypes of Ipomoea aquatica were pot-cultured on paddy soils with different pollution level of di-(2-ethylhexyl) phthalate (DEHP), and the concentrations of DEHP in plant and soil were determined by GC/MS. The results showed that the concentration of DEHP in plant varied directly with soil pollution level, and different genotypes of Ipomoea aquatica had significantly different concentrations of DEHP, which varied directly with leaf area. Soils grown with various genotypes of Ipomoea aquatica also had significantly different DEHP concentrations. The soil DEHP bioaccumulation factors (BCFs) of various Ipomoea aquatica genotypes were all under 1.0 and in inverse proportion to soil pollution level. The BCFs varied significantly among the genotypes of Ipomoea aquatica, with a relatively higher value for those genotypes with middle size leaves.

Four composting treatments for municipal sludge and rice straw were carried out, which included turning composting, inoculation-turning composting, continuous aeration, and intermittent aeration. GC/MS determination of phthalic acid esters (PAEs) in different composted composts showed that the total contents of six PAE compounds (sigma PAEs) ranged from 0.980-17.832 mg.kg-1, decreasing in the order of turning composting (17.832 mg.kg-1) > inoculation-turning composting (13.927 mg.kg-1) > intermittent aeration (10.765 mg.kg-1) > continuous aeration (9.815 mg.kg-1). DnOP was dominated in the composts. The degradation rate of sigma PAEs after composting was 1.37-45.71% (mean 27.63%), and that of diethyl phthalate (DEP), di-n-butyl phthalate (DnBP) and butylbenzyl phthalate (BBP) was 95.76-98.68%, 79.56-99.46% and 87.42-98.42%, respectively. The concentration of di-n-octyl phthalate (DnOP) was increased in the composts. Aeration-composting, and continuous aeration composting in particular, was more efficient than other treatments to degrade PAEs in municipal sludge.