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Catalytic performance decline is a general issue when shaping fine powder into macroscale catalysts (e.g., beads, fiber, pellets). To address this challenge, a phenolic resin-assisted strategy was proposed to prepare porous Co/N carbon beads (ZACBs) at millimeter scale via the phase inversion method followed by confined pyrolysis. Specially, p-aminophenol–formaldehyde (AF) resin-coated zeolitic imidazolate framework (ZIF-67) nanoparticles were introduced to polyacrylonitrile (PAN) solution before pyrolysis. The thermosetting of the coated AF improved the interface compatibility between the ZIF-67 and PAN matrix, inhibiting the shrinkage of ZIF-67 particles, thus significantly improving the void structure of ZIF-67 and the dispersion of active species. The obtained ZACBs exhibited a 99.9% removal rate of tetracycline (TC) within 120 min, with a rate constant of 0.069 min−1 (2.3 times of ZIF-67/PAN carbon beads). The quenching experiments and electron paramagnetic resonance (EPR) tests showed that radicals dominated the reaction. This work provides new insight into the fabrication of high-performance MOF catalysts with outstanding recycling properties, which may promote the use of MOF powder in more practical applications. [ABSTRACT FROM AUTHOR]

The mechanical response characteristics of large stone asphalt mixtures (LSAMs) are key factors in studying its fatigue characteristics during cyclic loading tests. Based on disturbed state concept (DSC) and viscoelastic continuum damage model (VECD), a series of tests using an overlay test (OT) were carried out to investigate the fatigue characteristics of LSAM. The results showed that disturbance and damage increased with decreasing frequency and increasing loading displacement and aging degree, while the asphalt content had no obvious adverse effect on the increase in damage. In addition, the disturbance and damage grew rapidly in the early stage of loading and reduced in the later stage of loading. On the contrary, based on DSC, the constitutive model modified with disturbance function (D) defined by external work could describe the mechanical properties, and the evolution process of disturbance function (D) could reflect the damage change in cyclic loading tests. The research conclusion can enrich the theoretical research on the fatigue failure response and mechanism of LSAM under cyclic loading and expand the application scope of DSC in the field of pavement. [ABSTRACT FROM AUTHOR]

A polydopamine (PDA)-assisted interface-induction strategy is proposed to transform Zn, Co-zeolitic imidazolate frameworks (ZIFs) into hollow cactus-like carbon sheet/carbon nanotubes (CS/CNTs) for electrocatalysis for the first time. The precursor Zn, Co-ZIFs@PDA was obtained by the coordination between Co2+ (from ZIFs) and N atoms (from PDA). The introduction of PDA achieves simultaneous rational optimization of the composition (N-doping) and structure (2D/1D) by the interface-induction and confinement effect. The advantageous structure and composition endow CS/CNTs with outstanding oxygen reduction reaction activity and durability in alkaline solution. [ABSTRACT FROM AUTHOR]

The performance of mixed matrix membranes (MMMs) substantively depends on the intrinsic structure and composition of the introduced nanofillers. In this work, pyrazole-based metal-organic frameworks (termed as MOF-303) were introduced into polymer of intrinsic microporosity (PIM-1) through a physical blending approach. Thanks to the well CO 2 -philic capability, high porosity, and appropriate pore structure of the incorporated MOF-303, the obtained MMMs exhibited remarkable separation performance. The improved CO 2 permeability and well-maintained CO 2 /CH 4 selectivity were achieved. Specifically, MMMs introducing 30 wt% MOF-303 loading exhibited a CO 2 /CH 4 selectivity of 27.6 and a high-CO 2 permeability of 7528.2 Barrer, which were 2.2 and 1.9 times greater than those of the unfilled PIM-1 membranes, respectively. Furthermore, a 33-h continuous separation test verified the excellent stability of the manufactured MMMs. More importantly, the MMMs showed significant resistance against physical aging, retaining up to 92.8% of their original CO 2 permeability after 150 days, compared to just 33.0% for control PIM-1 over the same period. Meanwhile, the plasticization resistance of the MMMs was reinforced compared to the unfilled PIM-1 membrane. This study potentially provides a novel approach for the rational design of MMMs in CO 2 separation applications. [Display omitted] • The CO 2 -philic MOF-303 nanofillers provided fast and selective transport channels for CO 2. • The prepared MMMs exhibit increased CO 2 permeability and CO 2 /CH 4 selectivity by 90.8% and 120.8%, respectively. • Long-term stable CO 2 /CH 4 separation and good antiaging performance were achieved. • MOF-303 improves CO 2 permeability by simultaneously enhancing solution and diffusion transport. [ABSTRACT FROM AUTHOR]

Rational design of fillers and polymers is of great importance to fabricate mixed matrix membranes (MMMs) with high performance. In this work, fluorinated metal-organic frameworks (KAUST-7 (also referred as NbOFFIVE-1-Ni)) were adopted as nanofillers to prepare MMMs through physically blending into the polymer of intrinsic microporosity (PIM-1). Benefiting from the features of porous KAUST-7, including well CO 2 affinity, distinctive pore characteristics (size, shape, and functionality) and strong intermolecular interactions with PIM-1, the achieved MMMs demonstrated increased CO 2 /CH 4 separation performance and improved anti-physical aging property. Specifically, with the assistance of KAUST-7, the CO 2 permeability and CO 2 /CH 4 (30:70 vol%) selectivity of the optimized MMMs increased up to 5928 Barrer and 23.5, corresponding to improvements of 50% of and 88% of the permeability and selectivity compared with the pristine membranes, respectively. Importantly, 100-h continuous separation test results confirmed the satisfying long-term stability of the prepared MMMs. Notably, the MMMs maintained 91% of the initial CO 2 permeability after 150 days (decreased only 539 Barrer), implying that the CO 2 permeability decrement is about 5-fold lower than that of the control PIM-1 membrane. These results suggest that the fabricated MMMs are promising candidates for CO 2 separation in practical applications. [Display omitted] • The CO 2 -philic KAUST-7 fillers were incorporated to PIM-1 for fabrication of MMMs. • The resultant MMMs exhibit enhanced CO 2 permeability and selectivity. • Long-term stable CO 2 /CH 4 separation and good antiaging performance were achieved. • Good interfacial compatibility between fillers and polymers results in the enhanced performance. [ABSTRACT FROM AUTHOR]

Persulfate-based advanced oxidation processes (PS-AOPs) have gained significant attention as an effective approach for the elimination of emerging organic contaminants (EOCs) in water treatment. Metal-organic frameworks (MOFs) and their derivatives are regarded as promising catalysts for activating peroxydisulfate (PDS) and peroxymonosulfate (PMS) due to their tunable and diverse structure and composition. By the rational nanoarchitectured design of MOF-derived nanomaterials, the excellent performance and customized functions can be achieved. However, the intrinsic fine powder form and agglomeration ability of MOF-derived nanomaterials have limited their practical engineering application. Recently, a great deal of effort has been put into shaping MOFs into macroscopic objects without sacrificing the performance. This review presents recent advances in the design and synthetic strategies of MOF-derived nano- and macroarchitectures for PS-AOPs to degrade EOCs. Firstly, the strategies of preparing MOF-derived diverse nanoarchitectures including hierarchically porous, hollow, yolk-shell, and multi-shell structures are comprehensively summarized. Subsequently, the approaches of manufacturing MOF-based macroarchitectures are introduced in detail. Moreover, the PS-AOP application and mechanisms of MOF-derived nano- and macromaterials as catalysts to eliminate EOCs are discussed. Finally, the prospects and challenges of MOF-derived materials in PS-AOPs are discussed. This work will hopefully guide the design and development of MOF-derived porous materials in SR-AOPs.

Single oxygen-based advanced oxidation processes ( 1 O 2 -AOPs) exhibit great prospects in selective degradation of organic pollutants. However, efficient production of 1 O 2 via tailored design of catalysts to achieve selective oxidation of contaminants remains challenging. Herein, we develop a simple strategy to regulate the components and coordination of Co-N-C catalysts at the atomic level by adjusting the Zn/Co ratio of bimetallic zeolitic imidazolate frameworks (Zn x Co 1 -ZIFs). Zn 4 Co 1 -C demonstrates 98% selective removal of phenol in the mixed phenol/benzoic acid (phenol/BA) solutions. Density functional theory calculations and experiments reveal that more active CoN 4 sites are generated in Zn 4 Co 1 -C, which are beneficial to peroxymonosulfate activation to generate 1 O 2 . Furthermore, the correlation between the origin of selectivity and well-defined catalysts is systematically investigated by the electron paramagnetic resonance test and quenching experiments. This work may provide novel insights into selective removal of target pollutants in a complicated water matrix.

Aidi injection (ADI), a traditional Chinese biomedical preparation, is a promising adjuvant therapy for gynecologic tumors (GTs), including cervical cancer (CC), endometrial cancer (EC), and ovarian cancer (OC). Although studies have reported positively on ADI therapy, its exact effects and safety in GT patients remain controversial. Therefore, a wide-ranging systematic search of electronic databases was performed for this meta-analysis. Data from 38 trials including 3309 GT patients were analyzed. The results indicated that the combination of conventional treatment and ADI markedly improved the patients' overall response rate (P<0.00001), disease control rate (P<0.00001), and quality of life (P<0.05) compared with conventional treatment alone. Furthermore, patient immunity was enhanced with combined treatment, as indicated by significantly increased percentages of CD3+ (P=0.005) and CD4+ (P<0.00001) and increased CD4+/CD8+ ratio (P=0.001). Most of the adverse events caused by radiochemotherapy such as gastrointestinal issues, leukopenia, thrombocytopenia, and hepatotoxicity, (P<0.05 for all) were significantly alleviated when ADI was used in the GT patients. However, other adverse events such as nephrotoxicity, diarrhea, alopecia, and neurotoxicity did not significantly differ between the two groups. Overall, these results suggest that the combination of conventional and ADI treatment is more effective than conventional treatment alone., (© 2021 The Author(s).)