29 research outputs found

    Three-Dimensional Homogeneous Ferrite-Carbon Aerogel: One Pot Fabrication and Enhanced Electro-Fenton Reactivity

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    This work focuses on constructing a high catalytic activity cathode of an electro-Fenton system, to overcome the defects of low activity, poor stability, and intricate fabrication of supported catalysts. A series of ferrite-carbon aerogel (FCA) monoliths with different iron/carbon ratios was synthesized directly from metal–resin precursors accompanied by phase transformation. Self-doped ferrite nanocrystals and carbon matrix were formed synchronously via moderate condensation and sol-gel processes, leading to homogeneous texture. An optimal 5% ferric content FCA was composed of coin-like carbon nano-plate with continuous porous structure, and the ferric particles with diameters of dozens of nanometers were uniformly embedded into the carbon framework. The FCA exhibited good conductivity, high catalytic efficiency, and distinguished stability. When it was used as an electro-Fenton cathode, metalaxyl degradation results demonstrated that 98% TOC elimination was realized after 4 h, which was 1.5 times higher than that of the iron oxide supported electrode. It was attributed to self-doped Fe@Fe<sub>2</sub>O<sub>3</sub> ensuring Fe­(II) as the mediator, maintaining high activity via reversibe oxidation and reduction by electron transfer among iron species with different valences. Meanwhile, an abundance of independent reaction microspaces were provided for every ferric crystal to in situ decompose electrogenerated H<sub>2</sub>O<sub>2</sub>. Moreover, the possible catalytic mechanism was also proposed. The FCA was a promising candidate as potential cathode materials for high-performance electro-Fenton oxidation

    Continuous Bulk FeCuC Aerogel with Ultradispersed Metal Nanoparticles: An Efficient 3D Heterogeneous Electro-Fenton Cathode over a Wide Range of pH 3–9

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    Novel iron–copper–carbon (FeCuC) aerogel was fabricated through a one-step process from metal-resin precursors and then activated with CO<sub>2</sub> and N<sub>2</sub> in environmentally friendly way. The activated FeCuC aerogel was applied in a heterogeneous electro-Fenton (EF) process and exhibited higher mineralization efficiency than homogeneous EF technology. High total organic carbon (TOC) removal of organic pollutants with activated FeCuC aerogel was achieved at a wide range of pH values (3–9). The chemical oxygen demand (COD) of real dyeing wastewater was below China’s discharge standard after 30 min of treatment, and the specific energy consumption was low (9.2 kW·h·kg<sup>–1</sup>COD<sup>–1</sup>), corresponding to a power consumption of only ∼0.34 kW·h per ton of wastewater. The enhanced mineralization efficiency of FeCuC aerogel was mostly attributable to ultradispersed metallic Fe–Cu nanoparticles embedded in 3D carbon matrix and the CO<sub>2</sub>–N<sub>2</sub> treatment. The CO<sub>2</sub> activation enhanced the accessibility of the aerogel’s pores, and the secondary N<sub>2</sub> activation enlarged the porosity and regenerated the ultradispersed zerovalent iron (Fe<sup>0</sup>) with reductive carbon. Cu<sup>0</sup> acted as a reduction promoter for interfacial electron transfer. Moreover, activated FeCuC aerogel presented low iron leaching (<0.1 ppm) in acidic solution and can be molded into different sizes with high flexibility. Thus, this material could be used as a low-cost cathode and efficient heterogeneous EF technology for actual wastewater treatment

    Electronic Control of Traditional Iron–Carbon Electrodes to Regulate the Oxygen Reduction Route to Scale Up Water Purification

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    Shifting four-electron (4e–) oxygen reduction in fuel cell technology to a two-electron (2e–) pathway with traditional iron–carbon electrodes is a critical step for hydroxyl radical (HO•) generation. Here, we fabricated iron–carbon aerogels with desired dimensions (e.g., 40 cm × 40 cm) as working electrodes containing atomic Fe sites and Fe3C subnanoclusters. Electron-donating Fe3C provides electrons to FeN4 through long-range activation for achieving the ideal electronic configuration, thereby optimizing the binding energy of the *OOH intermediate. With an iron–carbon aerogel benefiting from finely tuned electronic density, the selectivity of 2e– oxygen reduction increased from 10 to 90%. The resultant electrode exhibited unexpectedly efficient HO• production and fast elimination of organics. Notably, the kinetic constant kM for sulfamethoxazole (SMX) removal is 60 times higher than that in a traditional iron–carbon electrode. A flow-through pilot device with the iron–carbon aerogel (SA-Fe0.4NCA) was built to scale up micropolluted water decontamination. The initial total organic carbon (TOC) value of micropolluted water was 4.02 mg L–1, and it declined and maintained at 2.14 mg L–1, meeting the standards for drinking water quality in China. Meanwhile, the generation of emerging aromatic nitrogenous disinfection byproducts (chlorophenylacetonitriles) declined by 99.2%, satisfying the public safety of domestic water. This work provides guidance for developing electrochemical technologies to satisfy the flexible and economic demand for water purification, especially in water-scarce areas

    Clinicopathological characteristics of correlation of patients in pT3 EL (-),pT3 ELI (+) and pT3 ELI (-).

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    <p>Clinicopathological characteristics of correlation of patients in pT3 EL (-),pT3 ELI (+) and pT3 ELI (-).</p

    Clinicopathological characteristics of correlation of patients in pT3 ELI (+),pT3 ELI (-) and pT4a.

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    <p>Clinicopathological characteristics of correlation of patients in pT3 ELI (+),pT3 ELI (-) and pT4a.</p

    Dysfunction of multiple co-expressed microRNAs in a common disease.

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    <p>(A) The distribution of the number of miRNA pairs sharing a common disease from random selections of miRNA pairs. The number observed in the real conserved co-expression pairs (located by the blue arrow) is significantly higher than those in the randomly selected miRNA pairs (<i>p-value</i><0.001). (B) The distribution of the number of miRNA pairs sharing a common disease from random selections of disease miRNAs. The number observed in the real conserved co-expression pairs (located by the blue arrow) is significantly higher than those from the randomly selected disease miRNAs (<i>p-value</i><0.001). (C) The numbers of miRNAs associated with different human diseases in each sub-network.</p

    Enhanced Oxidative and Adsorptive Removal of Diclofenac in Heterogeneous Fenton-like Reaction with Sulfide Modified Nanoscale Zerovalent Iron

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    Sulfidation of nanoscale zerovalent iron (nZVI) has shown some fundamental improvements on reactivity and selectivity toward pollutants in dissolved-oxygen (DO)-stimulated Fenton-like reaction systems (DO/S-nZVI system). However, the pristine microstructure of sulfide-modified nanoscale zerovalent iron (S-nZVI) remains uncovered. In addition, the relationship between pollutant removal and the oxidation of the S-nZVI is largely unknown. The present study confirms that sulfidation not only imparts sulfide and sulfate groups onto the surface of the nanoparticle (both on the oxide shell and on flake-like structures) but also introduces sulfur into the Fe(0) core region. Sulfidation greatly inhibits the four-electron transfer pathway between Fe(0) and oxygen but facilitates the electron transfer from Fe(0) to surface-bound Fe­(III) and consecutive single-electron transfer for the generation of H<sub>2</sub>O<sub>2</sub> and hydroxyl radical. In the DO/S-nZVI system, slight sulfidation (S/Fe molar ratio = 0.1) is able to nearly double the oxidative removal efficacy of diclofenac (DCF) (from 17.8 to 34.2%), whereas moderate degree of sulfidation (S/Fe molar ratio = 0.3) significantly enhances both oxidation and adsorption of DCF. Furthermore, on the basis of the oxidation model of S-nZVI, the DCF removal process can be divided into two steps, which are well modeled by parabolic and logarithmic law separately. This study bridges the knowledge gap between pollutant removal and the oxidation process of chemically modified iron-based nanomaterials

    Functional relationships of 182 conserved co-expressed miRNA pairs.

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    <p>(A) Genomic distances of the observed miRNA pairs, which are significantly shorter than the distances of non co-expressed miRNA pairs (Wilcoxon rank sum test, <i>p-value</i><2.2e-16). (B) Probability density of the number of miRNA pairs that belong to the same cluster from randomly selected miRNA pairs. The count observed in the real co-expressed miRNA pairs (50, located by the blue arrow) is significantly higher than those in the random pairs (<i>p-value</i><0.001). (C) Probability density of the number of miRNA pairs that share common TFs from randomly selected miRNA pairs. The count observed in the real co-expressed miRNA pairs (47, located by the blue arrow) is significantly higher than those in the random pairs (<i>p-value</i><0.001). (D) Probability density of the number of miRNA pairs belonging to the same family from randomly selected miRNA pairs. The count observed in the real co-expressed miRNA pairs (44, located by the blue arrow) is significantly higher than those in the random pairs (<i>p-value</i><0.001). (E) The number of miRNA pairs with significantly overlapping targets in the real conserved co-expression pairs (132, located by the blue arrow) is significantly higher than those in the randomly selected miRNA pairs (<i>p-value</i> = 0.001). (F) The number of miRNA pairs with common targets significantly involved in at least one biological process in the real conserved co-expression pairs (88, located by the blue arrow) is significantly higher than those in the randomly selected miRNA pairs (<i>p-value</i> = 0.022). (G) The number of miRNA pairs with significantly overlapping expression-related genes in the real conserved co-expression pairs (81, located by the blue arrow) is significantly higher than those in the randomly selected miRNA pairs (<i>p-value</i> = 0.034).</p
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