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1.
Environ Res ; 228: 115854, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37037313

RESUMO

Bismuth oxide (BiO2-x) with oxygen vacancies was created using a hydrothermal process and was found to exhibit good catalytic oxidation performance under low-temperature heating without the addition of external oxidants. The catalytic activity of BiO2-x was tested using 4-chlorophenol (4-CP) as the target aqueous pollutant. We observed that 10 ppm of 4-CP was completely degraded within 40 min at a reaction temperature of 65 °C. The effective elimination of 4-CP was attributed to active oxygen species produced by the release of lattice oxygen. Furthermore, the low-temperature thermal catalytic activity of BiO2-x was affected by the electron transfer characteristics of pollutants, leading to the rapid degradation of electron-rich pollutants. This study reveals the unique application of BiO2-x as a catalyst for removing phenolic pollutants under low-temperature thermal catalysis, thereby expanding its catalytic application scenarios and offering a new approach for the degradation of phenolic pollutants.


Assuntos
Poluentes Ambientais , Temperatura , Óxidos , Oxirredução , Oxigênio , Catálise
2.
ChemSusChem ; 16(17): e202300468, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37161696

RESUMO

The surface reconstruction of transition metal-based catalysts has been demonstrated to be beneficial for oxygen evolution reaction (OER). However, regulating the activity and stability of the components derived from reconstruction is challenging. Here, a strategy of Fe3+ ion modulating the reconstruction components of CoN0.4 on a nitrogen-doped carbon carrier(CoN0.4 /NC) electrocatalyst for promoted OER activity and stability is reported. During the OER process, the cobalt nitride components on the surface of CoN0.4 /NC catalyst were converted into CoOOH and Co4+ species. The addition of Fe3+ stabilized the CoOOH phase and facilitated the formation of Fe-CoOOH active phase, enhancing the activity and stability of CoN0.4 /NC. The Fe10 -CoN0.4 /NC catalyst achieved a current density of 10 mA cm-2 at a low overpotential of 300 mV (vs. RHE) with a Tafel slope of 68.12 mV dec-1 . The overpotential of Fe10 -CoN0.4 /NC was 122 mV lower than that of the CoN0.4 /NC catalyst and was comparable to commercial RuO2 catalyst. This study develops a novel technology for regulating the production of reconstructed species using Fe3+ ions.

3.
Front Surg ; 9: 1037310, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36873806

RESUMO

Background: Cholangiocarcinoma (CCA) is primary liver cancer originating from the biliary tract. The epidemiology of CCA is diverse across the globe. There are no reliably effective options for systemic therapy and CCA outcomes are poor. Herein, we examined the association between overall survival and clinical characteristics of CCA patients in our region. Methods: We included 62 CCA cases diagnosed between 2015 and 2019. Demographics, clinical history, therapeutic procedures, and concomitant diseases were abstracted. Patient survival was obtained from a household registration system. Results: The cohort was 69% male and 31% female, with 26 (42%) iCCA, 27 (44%) pCCA, and 9 (15%) dCCA. No age differences were observed between the three subtypes. Bile duct and metabolic disorders were the major concomitant diseases and showed varying associations with CCA subgroups. Serum triglycerides (TG) were higher in pCCA and dCCA than iCCA patients (p < 0.05), and TG and total cholesterol (TC) were highest among pCCA patients with cholelithiasis. Liver function appeared significant difference between iCCA, pCCA and dCCA subtypes (p < 0.01), and also in the subgroups without cholelithiasis (p < 0.01). The obstructive jaundice in pCCA patients was associated with survival time after surgery, and the presence of cholelithiasis was also another influential factor. Conclusion: We found that pCCA was more frequently associated with metabolic disorders compared to iCCA and dCCA. Postoperative survival was also associated with the degree of jaundice in pCCA compared to iCCA or dCCA. And biliary drainage is an important predictor of outcome of pCCA.

4.
J Hazard Mater ; 436: 129123, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35596988

RESUMO

The efficient deployment of visible and near-infrared (NIR) light for photocatalytic disinfection is of great concern a matter. Herein, we report a specific bifunctional 2D/2D g-C3N4/BiO2-x nanosheets heterojunction, prepared through a self-assembly approach. Delightfully, the obtained 2D/2D heterojunctions exhibited satisfactory photocatalytic disinfection performance towards Escherichia coli K-12 (E. coli K-12) under visible light irradiation, which was credited to the Z-scheme interfacial heterojunction facilitating the migration of photogenerated carries. The photoactivity enhancement driven by NIR light illumination was ascribed to the cooperative synergy effect of photothermal effect and "hot electrons", engineering efficient charge transfer. Intriguingly, the carboxyl groups emerged on g-C3N4 nanosheets contributed a vital role in establishing the enhanced photocatalytic reaction. Moreover, the disinfection mechanism was systematically described. The cell membrane was destroyed, evidenced by the generation of lipid peroxidation reaction and loss of energy metabolism. Subsequently, the damage of defense enzymes and release of intracellular constituents announced the irreversible death of E. coli K-12. Interestingly enough, considerable microbial community shifts of surface water were observed after visible and NIR light exposure, highlighting the critical feature of disinfection process in shaping microbial communities. The authors believe that this work gives a fresh light on the feasibility of heterostructures-enabled disinfection processes.


Assuntos
Desinfecção , Escherichia coli K12 , Bactérias , Catálise , Escherichia coli , Luz
5.
J Hazard Mater ; 411: 125050, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33445050

RESUMO

The limited production of Cu+ in the Cu2+/PMS processes constrained its large-scan application for the elimination of organic pollutants. In this study, molybdenum powder (Mo) was applied as the co-catalyst to improve the degradation of 2,4-dichlorophenol (2,4-DCP) in Cu2+/PMS system at pH 5.6. By the assistance of Mo, Cu2+ was rapidly reduced to Cu+ which exhibited super activity for the peroxymonosulfate (PMS) activation. Compared with Cu2+/PMS processes, the PMS decomposition rate and 2,4-DCP degradation efficiency respectively increased by 62.1% and 83.6% in the Mo co-catalytic Cu2+/PMS system after reaction for 20 min. The degradation of 2,4-DCP was completed via both the free radical and non-radical pathways and the free radicals rather than Cu3+ contributed most to the reaction. In contrast to fresh Mo, the ratio of Mo4+ increased and Mo6+ decreased in the used Mo powder, due to the oxidation of Mo0 by Cu2+ and/or ∙OH and the reduction of Mo6+ by O2∙-. Additionally, the coexistence of Cl- and humic acid with low concentrations showed little effects on the Mo/Cu2+/PMS system while HCO3- presented an obvious depression for 2,4-DCP degradation. During five cycling runs, all the degradation rates were higher than 92.8%, indicating the good stability of Mo/Cu2+/PMS system.

6.
Chemosphere ; 262: 128067, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182131

RESUMO

The greatest constraint in the advanced oxidation processes involved Fe(II)/PMS was the low utilization of Fe(II) and PMS. In the present study, the co-catalytic effect of WS2 on the Fe(II)/PMS system for the degradation of organics was investigated. In the presence of WS2, Fe(III) was reduced to Fe(II) during the reaction and resulted in improved decomposition of PMS as well as the degradation of 4-chloriphenol (4-CP). The decomposition rate of PMS and degradation efficiency of 4-CP were 10% and 25% in the Fe(II)/PMS process, while the efficiencies respectively increased to 99% and 100% in the WS2 assisted Fe(II)/PMS system. The degradation of 4-CP was completed via the free radical pathway and SO4•- played a more important role than other active species. Low concentration of inorganic ions such as Cl- and HCO3- exhibited irrelevant effect while humic acid showed significant suppression on the WS2/Fe(II)/PMS system. Additionally, characterization and recycle results implied that WS2 maintained a good stability during the co-catalytic processes.


Assuntos
Compostos Férricos/química , Compostos Ferrosos/química , Sulfetos/química , Compostos de Tungstênio/química , Catálise , Clorofenóis/química , Poluentes Ambientais/química , Modelos Teóricos , Oxirredução , Peróxidos/química
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