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1.
Water Res ; 250: 121055, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38159544

RESUMEN

Low-pressure catalytic membranes allow efficient rejection of particulates and simultaneously removing organics pollutant in water, but the accumulation of dissolved organic matters (DOM) on membrane surface, which cover the catalytic sites and cause membrane fouling, challenges their stable operation in practical wastewater treatment. Here we propose a ferric salt-based coagulation/co-catalytic membrane integrated system that can effectively mitigate the detrimental effects of DOM. Ferric salt (Fe3+) serving both as a DOM coagulant to lower the membrane fouling and as a co-catalyst with the membrane-embedded MoS2 nanosheets to drive perxymonosulfate (PMS) activation and pollutant degradation. The membrane functionalized with 2H-phased MoS2 nanosheets showed improved hydrophilicity and fouling resistance relative to the blank polysulfone membrane. Attributed to the DOM coagulation and co-catalytic generation of surface-bound radicals for decontamination at membrane surface, the catalytic membrane/PMS/ Fe3+ system showed much less membrane fouling and 2.6 times higher pollutant degradation rate in wastewater treatment than the catalytic membrane alone. Our work imply a great potential of coagulation/co-catalytic membrane integrated system for water purification application.


Asunto(s)
Contaminantes Ambientales , Purificación del Agua , Molibdeno , Membranas Artificiales , Hierro , Materia Orgánica Disuelta
2.
Proc Natl Acad Sci U S A ; 119(31): e2201607119, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35878043

RESUMEN

Nonradical Fenton-like catalysis offers opportunities to overcome the low efficiency and secondary pollution limitations of existing advanced oxidation decontamination technologies, but realizing this on transition metal spinel oxide catalysts remains challenging due to insufficient understanding of their catalytic mechanisms. Here, we explore the origins of catalytic selectivity of Fe-Mn spinel oxide and identify electron delocalization of the surface metal active site as the key driver of its nonradical catalysis. Through fine-tuning the crystal geometry to trigger Fe-Mn superexchange interaction at the spinel octahedra, ZnFeMnO4 with high-degree electron delocalization of the Mn-O unit was created to enable near 100% nonradical activation of peroxymonosulfate (PMS) at unprecedented utilization efficiency. The resulting surface-bound PMS* complex can efficiently oxidize electron-rich pollutants with extraordinary degradation activity, selectivity, and good environmental robustness to favor water decontamination applications. Our work provides a molecule-level understanding of the catalytic selectivity and bimetallic interactions of Fe-Mn spinel oxides, which may guide the design of low-cost spinel oxides for more selective and efficient decontamination applications.


Asunto(s)
Electrones , Óxidos , Catálisis , Óxido de Magnesio/química , Óxidos/química , Peróxidos/química
3.
World J Pediatr ; 18(3): 176-185, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35089538

RESUMEN

BACKGROUND: Maternal smoking during pregnancy may be associated with low birth weight (LBW) in offspring and global risk estimates have not been summarized previously. We aimed to systematically explore evidence regarding maternal smoking and the LBW risk in offspring globally and examine possible causes of heterogeneity across relevant studies. METHODS: Comprehensive search of PubMed, Ovid Embase, Ovid Medline (R), and Web of science from inception until October 2021 was carried out. A random-effects meta-analysis was used to estimate the pooled odds ratio (OR) and corresponding 95% confidence interval (CI). Restricted cubic spline analysis with three knots was used to further examine the dose-response relationship. RESULTS: Literature searches yielded 4940 articles, of which 53 met inclusion criteria (comprising 55 independent studies). Maternal smoking during pregnancy was significantly associated with the risk of LBW in offspring (OR = 1.89, 95% CI = 1.80-1.98). Furthermore, an obvious dose-response relationship between the amount of cigarettes daily smoked in pregnancy and the risk of LBW in offspring was observed. The results of subgroup analyses indicated that the risk of maternal smoking on LBW was larger in more recently conducted studies (P = 0.020) and longer period of active smoking during pregnancy (P = 0.002). No evidence of publication bias was found. CONCLUSIONS: In summary, maternal smoking in pregnancy was significantly associated with a higher risk of LBW in offspring on a global scale. The risk of maternal smoking on infant LBW seems to be increasing over time, and was higher with longer smoking duration throughout pregnancy and more cigarettes smoked daily.


Asunto(s)
Recién Nacido de Bajo Peso , Fumar , Peso al Nacer , Estudios de Cohortes , Familia , Femenino , Humanos , Recién Nacido , Oportunidad Relativa , Embarazo , Fumar/efectos adversos , Fumar/epidemiología
4.
Fitoterapia ; 131: 134-140, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30292838

RESUMEN

Eight new triterpenoid saponins, including four ursane-type saponins, ilexchinenosides J-M (1-4), and four oleanane-type saponins, ilexchinenosides N-Q (5-8), along with three known triterpenoid saponins (9-11) were isolated from the leaves of Ilex chinensis Sims. Their structures were established by 1D, 2D NMR and MS spectroscopic analyses and through comparisons with known compounds. Moreover, compounds 1, 3, 5, 7-9 and 11 exhibited significant levels of hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in in vitro assays while compound 10 had moderately inhibitory effects on the NO production of lipopolysaccharide (LPS)-induced murine macrophages.


Asunto(s)
Ilex/química , Hojas de la Planta/química , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Animales , Células Hep G2 , Humanos , Macrófagos/efectos de los fármacos , Ratones , Estructura Molecular , Óxido Nítrico/metabolismo , Ácido Oleanólico/análogos & derivados , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/farmacología , Saponinas/farmacología , Triterpenos/farmacología
5.
Phytochemistry ; 148: 113-121, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29421508

RESUMEN

Eleven previously undescribed compounds including two triterpenes, ilexchinenin A and ilexchinenin B, and nine triterpenoid saponins, ilexchinenosides A-I, along with twelve known triterpenoids were isolated from the leaves of Ilex chinensis Sims (Aquifoliaceae). Their structures were elucidated by spectroscopic analysis and comparison with known compounds. Furthermore, eight compounds exhibited significant inhibitory effects on NO production of lipopolysaccharide (LPS)-induced murine macrophages, while nine compounds exhibited potent hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in in vitro assays.


Asunto(s)
Ilex/química , Triterpenos/aislamiento & purificación , Animales , Ilex/genética , Ilex/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Estructura Molecular , Hojas de la Planta/química , Raíces de Plantas/química , Saponinas/química , Triterpenos/química
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