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• Magnetite nanoparticle supported on sepiolite (Fe 3 O 4 -Sep) was fabricated. • Fe 3 O 4 -Sep showed high adsorption ability toward BPA. • Adsorbed BPA can be degraded in-situ via Fenton-like process. • Columnar Fe 3 O 4 -Sep remained stable in the fixed-bed reactor under continuous-flow. • Influence of real water matrix on the combined processes was negligible. In this work, a magnetic sepiolite composite was prepared by chemical co-precipitation method and firstly applied as both adsorbent and catalyst for the removal of bisphenol A (BPA) through a heterogeneous Fenton process. The composite was characterized by XPS, XRD, SEM and TEM techniques. The results of the kinetics study indicate that BPA (50 mg·L−1) can be adsorbed onto the composite via electrons transfer as well as π-π interaction, and then be completely degraded at pH 6.0 within 30 min after the addition of H 2 O 2 (1000 mg·L−1). The analysis of FTIR confirms that the degradation occurred through a combined process of adsorption and oxidation. BPA was pre-concentrated and fixed onto the composite surface and then degraded in-situ by hydroxyl radicals, which were generated through the interaction between H 2 O 2 and surface active sites. To investigate the stability and regeneration properties of the catalyst, the powder composite was extruded into a small cylindrical sample and loaded in a fixed-bed reactor, which was operated under continuous-flow condition. The BPA removal efficiency after 4 h remained at 87%, while the leaching of Fe ions gradually increased. Further, degradation tests in different real waters including tap water and municipal wastewater spiked with BPA (50 μg·L−1) reveal that the influence of real matrix on the oxidation ability was very little. The findings of this study confirm the composite as a promising material for the catalytic removal of organics via the coupled adsorption-oxidation process. [ABSTRACT FROM AUTHOR]

Highlights • The MW-Fe0/H 2 O 2 process was used to treat concentrated landfill leachate. • Reaction parameters and the degradation mechanism were systematically studied. • Refractory organics were degraded by the synergistic effects of MW, Fe0 and H 2 O 2. • Various analyses proved that refractory organics were efficiently degraded. • The reaction mechanism of the MW-Fe0/H 2 O 2 process has wide applicability. Abstract To study the treatment effect and mechanism of a combined microwave (MW)-Fe0/H 2 O 2 Fenton-like process on concentrated landfill leachate, the effects of initial pH, Fe0 dosage, H 2 O 2 dosage, MW power and reaction time on the removal of organic substances were investigated. The phase change of Fe0 before and after reaction and its catalytic mechanism were investigated using multiple analytical techniques. Results showed that the removal efficiencies of chemical oxygen demand, UV 254 and color number were 58.70%, 85.69% and 88.30%, respectively, at initial pH of 2.0, Fe0 dosage of 0.5 g/L, H 2 O 2 dosage of 20 mL/L, MW power of 400 W and reaction time of 14 min. Comparison of different Fenton-like processes indicated that the MW-Fe0/H 2 O 2 Fenton-like process was the most efficient and significantly decreased the aromaticity degree, molecular weight and condensation degree of organic substances in the leachate. The fluorescence peak of concentrated leachate exhibited a blue-shift in the MW-Fe0/H 2 O 2 process, further indicating that the condensation degree of humic substances declined and molecular weight remarkably decreased. The mechanism exhibited an advanced oxidation effect of a heterogeneous Fenton reaction between iron oxide and H 2 O 2 , as well as of adsorption and precipitation effects of iron-based colloids, on organic substances. Moreover, thermal and non-thermal effects of MW accelerated these reactions, achieving fast removal of organic pollutants in the concentrated landfill leachate. Overall, the results of this study showe that the MW-Fe0/H 2 O 2 process is an effective and promising method to handle concentrated landfill leachate. [ABSTRACT FROM AUTHOR]

• DOM composition in landfill and incineration leachate was systematically compared. • Transformations of the DOM molecular compositions by MBR/NF were investigated. • Phenolic compounds, polyphenols and polycyclic aromatics enriched in MBR leachate. • NF lowered the DOM abundances but with more complex DOM in the NF concentrate. • Coagulation in conjunction with an advanced O 3 /H 2 O 2 process was used to treat NF concentrate. Transformations of the molecular compositions of dissolved organic matter (DOM) in incineration leachate (IL) were investigated. Results revealed that DOM in IL had a lower oxidation degree than that in mature MSW landfill leachate (LL). Moreover, aliphatic compounds (2.0 ≥ H/C ≥ 1.5) having the highest bioavailability were the most abundant type of DOM in IL, making IL significantly more biodegradable than LL. Under microbial actions, etc., DOM composed of phenolic compounds (aromaticity index (AI) ≤ 0.50 and H/C < 1.5), polyphenols (0.66 ≥ AI > 0.50) and polycyclic aromatics (AI > 0.66) in MBR-treated effluents were enriched and more diverse than in the untreated leachates. Nanofiltration (NF) dramatically lowered the relative abundances of phenolic compounds, polyphenols and polycyclic aromatics in effluent generated by treatment of IL in a MBR. Although the concentration of DOM in NF effluent was comparatively low, the DOM compositions in the resulting NF concentrate were nearly identical to those in MBR effluent, but were more complex than those in an international standard DOM due to a higher content of CHOS and CHONS heteroatomic compounds. Particularly, coagulation in conjunction with ozone/hydrogen peroxide oxidation process were dramatically reduced most polyphenols and polycyclic aromatics from the NF concentrate. [ABSTRACT FROM AUTHOR]

• Cartilage decellularized matrix (CDM) is processed into inks for 3D printing. • CDM-based scaffolds with controlled 3D shape and pore structure are obtained. • Fibers can improve the mechanical property of 3D-printed CDM scaffolds. • 3D-printed fiber-reinforced CDM scaffolds exhibit elasticity in wet condition. • Fiber-reinforced CDM scaffolds can repair articular cartilage defects in rabbits. Cartilage decellularized matrix (CDM) is considered a promising biomaterial for fabricating cartilage tissue engineering scaffolds. An ideal CDM-based scaffold should possess customizable 3D shape for complex tissue regeneration and proper pore size for cell infiltration, as well as provide mechanical support for cell growth. 3D printing is an efficiently technique for preparing customizable 3D scaffolds, however, fabricating CDM-based 3D-printed scaffolds with customizable shapes, proper pore structure and satisfactory mechanical properties remains a challenge. In the current study, to achieve customizable CDM-based 3D scaffolds, CDM was successfully processed into inks suitable for 3D printing. Further, the poor mechanics of CDM-based scaffolds were significantly improved by adding electrospinning fiber into the CDM-based inks for 3D printing. Importantly, the 3D-printed electrospinning fiber-reinforced CDM-based scaffold presented good biocompatibility and can enhance repair articular cartilage defects in rabbits. The current study provides a novel strategy for printing electrospinning fiber-reinforced CDM-based scaffolds for tissue regeneration. [ABSTRACT FROM AUTHOR]

• MW-PS-H 2 O 2 binary-oxidant process was firstly used to treat DDNP wastewater. • The oxidant utilization rate considerably increased with the binary oxidant process. • Both S O 4 · - and · O H were major contributions to organics degradation. Microwave (MW) irradiation is a superior approach to a warm-up system than conventional heating, and persulfate (PS) and hydrogen peroxide (H 2 O 2) can be efficiently activated to produce a reactive oxygen species for organic degradation. However, shortcomings remain regarding whether to use a low oxidant or the low treatment efficiency of a single oxidant process. In this study, a PS-H 2 O 2 binary oxidant process induced by MW was developed to treat dinitrodiazophenol industrial wastewater. The best chemical oxygen demand (COD) (73.5%) and color number (CN) (98.1%) removal efficiencies were obtained for the MW-PS-H 2 O 2 process under conditions of a total oxidant dose = 7.4 mM and n(PS)/n(H 2 O 2) = 3.7/3.7. In the MW-PS-H 2 O 2 process, the combination of ·OH and SO 4 − better degrades organics in DDNP industrial wastewater with the advantages of lower residual salinity (sulfate ions) and less invalid decomposition of excessive H 2 O 2. In addition, benzene ring substances and functional group substances were greatly degraded, and the molecular weight of the organics considerably decreased as a result of the MW-PS-H 2 O 2 process. Overall, the results demonstrate that the MW-PS-H 2 O 2 process is a promising treatment method for dinitrodiazophenol industrial wastewater with high treatment efficacy and high oxidant utilization. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Degradation of BPA was investigated by · OH - and SO 4 · - - AOPs. • The TOC removal rate achieved 36% and 24% for the catalyzed H 2 O 2 and persulfate. • BPA followed different transformation pathways in two systems. • The less radical scavenging may led to the higher removal of BPA by catalyzed H 2 O 2. • The magnetic fly ash presented good structural stability during the recycle runs. Abstract In this study, H 2 O 2 and persulfate (PS) were both proved to be heterogeneously catalyzed by the Fe 3 O 4 nanoparticle supported on coal fly ash for reactive oxidation species (ROS). The two heterogeneous advanced oxidation processes (AOPs) were systematically investigated, and the system with H 2 O 2 exhibited higher reactivity for Bisphenol A (BPA) elimination and total organic carbon (TOC) reduction. The two systems were comprehensively compared in terms of degradation kinetics, transformation way, water matrix species and catalyst stability. Systems with H 2 O 2 and PS can remove 100% and 80.2% of the BPA after 120 min (0.22 mmol/L), respectively([H 2 O 2 ] = 22 mmol/L, [PS] = 22 mmol/L). The oxidant efficiency in system with H 2 O 2 was obviously higher probably due to the less radical scavenging. A mechanism was proposed that the interface interactions between solid and liquid phase will affect the collision among molecular of oxidants and catalyst, as well as the lifetime of radicals during the their diffusion process. The quenching experiments demonstrated that the primary radical species in two systems were · OH and SO 4 · - / · OH , respectively, thus causing the different BPA degradation pathways and by-products. The catalyst presented good structural stability and relatively low Fe leaching in both systems during the recycle. The valence state transformation from Fe2+ to Fe3+ after the reaction explained the gradual catalytic activity loss. In the tap water and municipal wastewater, the system with PS was less influenced by the real water matrix due to the lower university of SO 4 · - toward organics. [ABSTRACT FROM AUTHOR]

Highlights • A heterogeneously catalyzed H 2 O 2 /persulfate system was investigated. • Bisphenol A can be effectively degraded in the binary oxidants system. • The oxidants ratios and solution pH affected the system efficiency and radicals. Abstract Bisphenol A is one of the typical endocrine chemicals that can be found in many different kinds of water bodies. A heterogeneously catalyzed H 2 O 2 /peroxydisulfate system coupled with magnetite supported on coal fly ash was investigated for the degradation of bisphenol A. The activity tests results showed that the bisphenol A (50 mg/L) degradation efficiency of 60 min in the binary oxidants system can be significantly enhanced from 16.7% to 100% after the addition of catalyst ([oxidants] 0 = 20 mM, [H 2 O 2 ] 0 /[PDS] 0 = 4, [Catalyst] = 2 g/L, pH = 5, T = 25 °C), while the oxidation process can be affected by solution pH, catalyst surface properties and oxidant ratios. Based on the results of quenching experiments, it was proposed that in a binary system, there were 3 radicals including hydroxyl radical, sulfate radical and superoxide radical possibly responsible for the bisphenol A degradation, and either radical may predominate over the other two depending on the adsorption behaviors on the catalyst surface as well as the radicals' inter-conversions. The stability and reusability analysis of catalyst were carried out in 7 sequential batch studies. The negligible concentration of dissolved Fe ion in first 4 runs illustrated the dominant role of heterogeneous process, while the gradually leached Fe ion in following runs demonstrated the involvement of homogeneous process. The findings of this study strongly suggest that the heterogeneous binary oxidant system is a promising treatment technology for the abatement of bisphenol A, while the suitable oxidant ratio and solution pH are essential for making the most of the radicals. [ABSTRACT FROM AUTHOR]

By fully utilizing the abundant surface functional groups of the fungus to coordinate with metal cobalt ions and the phosphorus and nitrogen elements of the organism itself to regulate the coordination environment of the central metal atoms, a cobalt-based single-atom catalyst TAHCF/Co-N was successfully constructed for selective hydrogenation of nitroaromatic compounds with good performance. [Display omitted] • Hyphae could be biocultured into macroscopic 3D structure. • Hyphae have natural functional groups for anchoring metal ions. • Fungal phosphorus sources could tailor the coordination of single metal sites. • The catalyst exhibits impressive performance for nitroarene hydrogenation. Utilizing biomass as a versatile catalyst building platform holds tremendous promise for catalyst design. In this study, we demonstrate a facile and effective method to fabricate high-performance catalysts using Trichoderma afroharzianum hyphae derived carbon fiber (TAHCF) embedded with Co 1 -N 3 P 1 active sites for nitroaromatic hydrogenation. This strategy leverages the intrinsic self-assembly and metal ion adsorption capabilities of Trichoderma afroharzianum (TA). During the carbonization process, amino acid-rich fungi undergo transformation into biochar substrates co-doped with functional heteroatoms, facilitating the creation of TAHCF single-atom catalyst. Moreover, the catalytic performance can be further enhanced by tailoring the coordination structure of metal atoms on the carbon substrates. Remarkably, we achieve a high turnover frequency of 1553 h−1 for the hydrogenation of nitrobenzene, along with exceptional conversion and selectivity for various nitro compounds with the metal loading as low as 0.02 wt%. Our study presents a characteristic synthetic method that advances the design of single-atom catalysts by leveraging the inherent structure characteristics of biomass in the pursuit of energy sustainability. [ABSTRACT FROM AUTHOR]

The development of a biomimetic surface which is able to promote endothelialization is fundamental in the research for blood vessel substitutes to overcome the formation of thrombi or hyperplasia. In the present work, the fabrication of acrylamide-terminated glycine-arginine-glycine-aspartic peptides (Ac-GRGD) modified poly(ester-urethane) urea (PEUU) nanofibrous mats via electrospinning technique followed by covalent immobilizing method for improving its endothelialization was successfully achieved. Series of PEUU based polymers including PEUU, PEUU with t-butoxycarbonyl group (PEUU-Boc), and PEUU-amino group (PEUU-NH 2 ) were synthesized by a two-step solution polymerization and a de-protection process. The PEUU-RGD as-prepared nanofibrous mat was characterized using different techniques, such as, scanning electron microscopy, solide-state 13 C CP-MAS nuclear magnetic resonance, and stress-strain test. In addition, to motivate cell adhesion and proliferation, PEUU nanofibers mat was immobilized by coupling of Ac-GRGD. The results present that incorporation of Ac-GRGD peptide improved the mechanical properties and does not have negative effect on the morphology and the structure of PEUU nanofibers. From cell viability and cell morphology results, the prepared PEUU-RGD nanofiber mats are cytocompatible. Interestingly, the immobilized PEUU-RGD nanofibers possess lower hemolysis rate and an improved inhibition of platelet adhesion. Overall, Ac-GRGD peptides immobilized PEUU nanofibrous mats may have a potential application for vascular tissue engineering. [ABSTRACT FROM AUTHOR]