The rational modulation of metal catalysts with tailorable valence and redox properties is a promising strategy for further improving their catalytic performance. Herein, an environment-friendly grafting and thermal strategy was adopted to immobilize copper oxides nanoparticles on carbon nanofiber (CuOx/CF). Benefiting from the defect-rich surface and valence-mixed composition of the CuOx species, the optimized sample CuOx/CF-3 exhibits superb activity for the catalytic reduction of toxic nitrophenols. The complete conversion took only 1 min and an outstanding rate constant (k) of 112.7 × 10˗3 s˗1 was achieved under mild conditions (25 °C and 1 atm). Kinetic and recycle experiments demonstrated that the whole catalytic process obeys a pseudo-order kinetic, and the catalyst could maintain high conversion even after 13 successive recycles. These results demonstrate that CuOx/CF-3 is an alternative catalyst to noble metals, providing superb catalytic efficiency and stability in the reduction of toxic nitrophenols, and it can be expanded to develop other noble-metal-free catalysts for various applications.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
The efficient carbon supports change not only the physical but also the chemical properties of iron oxide and create new active sites for the enhancement of catalytic activity in the oxidation of alcohols with air as an oxygen source.
The pore structure and adsorption sites are considered to be the performance determinants for adsorbent during removing of environmental pollutants. Herein, we designed a new Quasi-MIL-125(Ti) with hierarchical pores and adsorption sites via a temperature-controlled thermolysis strategy at an optimized temperature of 340 °C. The Quasi-MIL-125(Ti) achieved an ultra-fast and efficient adsorption for cationic dyes, especially for methylene blue (MB) and neutral red (NR), no matter in single or binary systems within 1 min. Adsorption isotherm shows that dyes adsorption on Quasi-MIL-125(Ti) follow a Langmuir adsorption isotherm model. The experimental maximum adsorption capacities were 109.3 mg g-1 for MB and 151.1 mg g-1 for NR, respectively. Adsorption mechanism reveals that the strong electrostatic attraction originated from the unsaturated Ti sites in Quasi-MIL-125(Ti) contribute to the ultra-fast adsorption behavior during cationic dyes chemisorption process. Meanwhile, the coexisting micro- and mesopores also facilitates the diffusion and co-adsorption of different dye molecules. This study not only provides a promising prospect for the synthetic strategy of super-adsorbents, but also provides reference and theoretical guidance for practical dye wastewater treatment.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Insensitivity and resistance to 5-fluorouracil (5FU) remain as major hurdles for effective and durable 5FU-based chemotherapy in colorectal cancer (CRC) patients. In this study, we identified prostaglandin E synthase (PTGES)/prostaglandin E2 (PGE2) axis as an important regulator for 5FU sensitivity in CRC cells. We found that PTGES expression and PGE2 production are elevated in CRC cells in comparison to normal colorectal epithelial cells. Depletion of PTGES significantly enhanced the inhibitory effect of 5FU on CRC cell viability that was fully reverted by exogenous supplement of PGE2. Inhibition of PTGES enzymatic function, by either inducing loss-of-function mutant or treatment with selective inhibitors, phenocopied the PTGES depletion in terms of 5FU sensitization. Mechanistically, PTGES/PGE2 axis modulates glycolysis in CRC cells, thereby regulating the 5FU sensitivity. Importantly, high PTGES expression is correlated with poor prognosis in 5FU-treated CRC patients. Thus, our study defines PTGES/PGE2 axis as a novel therapeutic target for enhancing the efficacy of 5FU-based chemotherapy in CRC.