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[Display omitted] Anti-tumor therapies reliant on reactive oxygen species (ROS) as primary therapeutic agents face challenges due to a limited oxygen substrate. Photodynamic therapy (PDT) is particularly hindered by inherent hypoxia, while chemodynamic therapy (CDT) encounters obstacles from insufficient endogenous hydrogen peroxide (H 2 O 2) levels. In this study, we engineered biodegradable tumor microenvironment (TME)-activated hollow mesoporous MnO 2 -based nanotheranostic agents, designated as HAMnO 2 A. This construct entails loading artemisinin (ART) into the cavity and surface modification with a mussel-inspired polymer ligand, namely hyaluronic acid-linked poly(ethylene glycol)-diethylenetriamine-conjugated (3,4-dihydroxyphenyl) acetic acid, and the photosensitizer Chlorin e6 (mPEG-HA-Dien-(Dhpa/Ce6)), facilitating dual-modal imaging-guided PDT/CDT synergistic therapy. In vitro experimentation revealed that HAMnO 2 A exhibited ideal physiological stability and enhanced cellular uptake capability via CD44-mediated endocytosis. Additionally, it was demonstrated that accelerated endo -lysosomal escape through the pH-dependent protonation of Dien. Within the acidic and highly glutathione (GSH)-rich TME, the active component of HAMnO 2 A, MnO 2 , underwent decomposition, liberating oxygen and releasing both Mn2+ and ART. This process alleviates hypoxia within the tumor region and initiates a Fenton-like reaction through the combination of ART and Mn2+, thereby enhancing the effectiveness of PDT and CDT by generating increased singlet oxygen (1O 2) and hydroxyl radicals (•OH). Moreover, the presence of Mn2+ ions enabled the activation of T 1 -weighted magnetic resonance imaging. In vivo findings further validated that HAMnO 2 A displayed meaningful tumor-targeting capabilities, prolonged circulation time in the bloodstream, and outstanding efficacy in restraining tumor growth while inducing minimal damage to normal tissues. Hence, this nanoplatform serves as an efficient all-in-one solution by facilitating the integration of multiple functions, ultimately enhancing the effectiveness of tumor theranostics. [ABSTRACT FROM AUTHOR]

The contaminant status, spatial distribution, partitioning behavior, and ecological risks of 26 legacy and emerging perfluoroalkyl and polyfluoroalkyl substances (PFASs) in Laizhou Bay, China were investigated. The concentrations of ∑PFASs in surface and bottom seawater ranged from 37.2 to 222 ng/L and from 34.2 to 305 ng/L with an average of 116 ± 62.7 and 138 ± 93.8 ng/L, respectively. There were no significant differences in the average concentrations between the surface and bottom seawater (P > 0.05). Perfluorooctanoic acid (PFOA) and short-chain PFASs dominated the composition of PFASs in seawater. The concentrations of ∑PFASs in sediments ranged from 0.997 to 7.21 ng/g dry weight (dw), dominated by perfluorobutane sulfonate (PFBS), perfluorobutanoic acid (PFBA), and long-chain PFASs. The emerging alternatives of perfluoro-1-butane-sulfonamide (FBSA) and 6:2 fluorotelomer sulfonic acid (6:2 FTSA) were detected for the first time in Laizhou Bay. The ∑PFASs in seawater in the southwest of the bay were higher than those in the northeast of the bay. The ∑PFASs in sediments in the northeast sea area were higher than those in the inner area of the bay. Log K d and log K oc values increased with increasing carbon chain length for PFASs compounds. Ecological risk assessments indicated a low ecological risk associated with HFPO-DA but a moderate risk associated with PFOA contamination in Laizhou Bay. Positive matrix factorization (PMF) analysis revealed that fluoropolymer manufacturing, metal plating plants, and textile treatments were identified as major sources contributing to PFASs contamination. [Display omitted] • Widespread contamination of PFASs occurred in Laizhou Bay. • PFOA was the major contaminant in the environmental samples of Laizhou Bay. • HFPO-DA and FBSA as emerging alternatives were detected in all water samples. • FBSA and 6:2 FTSA were detected for the first time in Laizhou Bay. • The carbon chain length affected the distribution of PFASs in water and sediment. [ABSTRACT FROM AUTHOR]

Three morphologies of ZnO [spherical (S), rod (R) and disk (D)] were synthesized and tested as supports for Au nanoparticles for the selective oxidation of glycerol, 1,2-propanediol, 1,2-butanediol, and isopropanol at their secondary hydroxyl group to produce the corresponding ketones. The Au-ZnO(0 0 1) interface exhibits a strong electron sink effect and abundant oxygen vacancies, greatly promoting the adsorption of O 2 and the adsorption and conversion of polyols at their secondary hydroxyl moiety. Moreover, the as-formed Auδ+-OH* site resulting from O 2 activation can efficiently extract the hydrogen of the C-H bond of the key RCHO*CH 2 OH intermediate on the Zn-O v site of ZnO(0 0 1) surfaces. Therefore, the Au/ZnO-D exhibits superior catalytic activity (turnover frequency >500h−1) and ketone selectivity (>80 %) than other catalysts with different ZnO facets exposed. [Display omitted] • Three morphologies of ZnO [spherical (S), rod (R) and disk (D)] were synthesized to support Au nanoparticles. • Au/ZnO-D exhibits superior catalytic activity and ketone selectivity. • Au-ZnO(0 0 1) interface exhibits a strong electron sink effect and abundant oxygen vacancies. • Auδ+-OH* site can efficiently extract the hydrogen of the C-H bond of the key RCHO*CH 2 OH intermediate. In-depth understanding and precise tuning of the crystal facet-dependent catalytic properties of supported catalysts are critical for polyol oxidation. Herein, we report a crystal-facet-dependent study of Au-ZnO interfaces for the selective promotion of the oxidation of various polyols and alcohols (glycerol, 1,2-propanediol, 1,2-butanediol, and isopropanol) at the secondary hydroxyl position to produce the corresponding ketones. Three facets of the zinc oxide support, ZnO(1 0 1), ZnO(1 0 0) and ZnO(0 0 1), associated with nanoparticles of various morphologies (spherical (S), rod (R) and disk (D), respectively), were found to induce different electronic local environments and surface oxygen vacancy contents at the Au-ZnO interface. In particular, the ZnO(0 0 1) facet dominating in the Au/ZnO-D nanoparticles can store more electrons from Au, and such electron sink effect, together with the generation of oxygen vacancies (Zn-O v), synergistically enhances the adsorption of O 2 and polyols at the secondary hydroxyl position. Moreover, it was determined that the as-formed Auδ+-OH* site resulting from O 2 activation can efficiently extract the hydrogen of the C-H bond of the key RCHO*CH 2 OH intermediate on the Zn-O v site of ZnO(0 0 1) surfaces. Consequently, the Au/ZnO-D catalyst exhibits unprecedented catalytic activity (turnover frequency >500 h−1) and ketone selectivity (>80 %) for glycerol oxidation. [ABSTRACT FROM AUTHOR]

Iodinated contrast media (ICM), one of the pharmaceutical and personal care products (PPCPs), are frequently detected in various water bodies due to the strong biochemical stability and recalcitrance to conventional water treatment. Additionally, ICM pose a risk of forming iodinated by-products that can be detrimental to the aquatic ecosystem. Consequently, effectively removing ICM from aqueous environments is a significant concern for environmental researchers. This article provides a comprehensive review of the structural characteristics of ICM, their primary source (e.g., domestic and hospital wastewater), detected concentrations in water environments, and ecological health hazards associated with them. The current wastewater treatment technologies for ICM control are also reviewed in detail with the aim of providing a reference for future research. Prior researches have demonstrated that traditional treatment processes (such as physical adsorption, biochemical method and chemical oxidation method) have inadequate efficiencies in the removal of ICM. Currently, the application of advanced oxidation processes to remove ICM has become extensive, but there are some issues like poor deiodination efficiency and the risk of forming toxic intermediates or iodinated by-products. Conversely, reduction technologies have a high deiodination rate, enabling the targeted removal of ICM. But the subsequent treatment issues related to iodine (such as I− and OI−) are often underestimated, potentially generating iodinated by-products during the subsequent treatment processes. Hence, we proposed using combined reduction-oxidation technologies to remove ICM and achieved synchronous control of iodinated by-products. In the future, it is recommended to study the degradation efficiency of ICM and the control efficiency of iodinated by-products by combining different reduction and oxidation processes. [Display omitted] • Overview of ICM environmental pollution and fate. • Poor deiodination efficiency of ICM and the generation of iodinated by-products in AOPs. • High deiodination rate in reduction methods but removed iodide poses potential risk. • Combine reduction and oxidation processes to remove ICM and control I-DBPs. [ABSTRACT FROM AUTHOR]

Moderate WO x surface density of Ni/WO x -ZrO 2 with higher Brønsted/Lewis acid sites ratio enhances LDPE hydrocracking and obtains the maximum liquid yield. [Display omitted] • The non-noble Ni catalysts achieves the LDPE hydrocracking process under a mild condition. • The Ni/WO x -Zr catalysts achieves 100 % LDPE conversion with 76.9 % liquid yield. • The WO x surface density shows a volcanic-shape relationship with the B/L ratio of catalyst. • The LDPE hydrocracking performance has a linear relationship with the B/L ratio of catalyst. Chemical upcycling through catalytic hydrocracking to fuels has potential to mitigate the serious environmental issues caused by plastic waste. Herein, non-noble tungstate-zirconia supported nickel catalyst (Ni/WO x -ZrO 2) with tunable Brønsted/Lewis (B/L) ratio was firstly proposed for the hydrocracking of low-density polyethylene (LDPE), which achieves hydrogenation/dehydrogenation on Ni sites and cracking/isomerization on WO x -ZrO 2 , respectively. Excellent 100 % LDPE conversion with 76.9 % liquid yield was achieved, which is comparable to noble Ru-based and Pt-based catalysts. Quantitative linear relationship between B/L ratio and hydrocracking performance was established, and the key to boost performance was keenly controlling the volcanic-shape relationship between surface WO x density and B/L ratio of catalyst. Moderate WO x surface density with higher B/L ratio enhances LDPE hydrocracking, and inhibits the hydrogenation of the primary products. However, excessive WO x polymerized and formed WO 3 crystals, compensating acid sites and inhibiting LDPE hydrocracking. This work is of prime scientific and industrial significance to the rational design of catalysts for industrial plastic hydrocracking. [ABSTRACT FROM AUTHOR]

We construct defective Auδ−-O v interfacial structures by tuning the calcination temperature of ZrO 2 support to boost the oxidation of amino alcohols to amino acids. Finally, the Au/ZrO 2 -600 catalyst with rich defective Auδ−-O v interfacial sites exhibits 98.8% product yield for the oxidation of diethanolamine to iminodiacetic acid at only 30 °C. The catalyst system is further extended to the oxidation of other amino alcohols, involving monoethanolamine and triethanolamine, to their corresponding amino acids with excellent catalytic performance. [Display omitted] • Defective Au-ZrO 2 interfacial structure was constructed by tuning the calcination temperature of ZrO 2 support. • The Auδ−-O v interfacial site displays the unique synergistic adsorption effect and electron transfer ability. • O v site prioritizes the adsorption of amino groups in amino alcohols, avoiding the occupation of Auδ− main sites. • Electron-rich Auδ− nearby O v site adsorbs the hydroxyl groups and activates the C-H bond activation of NH 2 CH 2 CH 2 O* intermediates. Designing efficient active sites to facilitate the oxidation of hydroxyl group to carboxylic acid under the influence of nitrogen-containing functional groups is worth exploring, but it is rarely investigated. Herein, we construct defective Au-ZrO 2 interfacial structures by tuning the calcination temperature of ZrO 2 support to boost the oxidation of amino alcohols to amino acids. Interestingly, the modification of calcination temperature induces the escape of saturated coordination oxygen atoms in ZrO 2 support, leaving behind abundant surface oxygen vacancy (O v). The as-formed Auδ−-O v interfacial site displays the unique synergistic adsorption effect and electron transfer ability. Specifically, the O v site voluntarily adsorbs the –NH 2 group of amino alcohol, thus ensuring that the electron-rich Auδ− nearby O v site adsorbs the hydroxyl groups and activates the C-H bond activation of NH 2 CH 2 CH 2 O* intermediates. Consequently, Au/ZrO 2 -600 catalyst with more defective Auδ−-O v interfacial sites exhibits 98.8 % product yield for the oxidation of diethanolamine to iminodiacetic acid at only 30 °C. The catalyst system is further extended to the oxidation of other amino alcohols, involving monoethanolamine and triethanolamine, to their corresponding amino acids with excellent catalytic performance. [ABSTRACT FROM AUTHOR]