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1.
J Environ Manage ; 365: 121524, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38897082

RESUMEN

Thallium (Tl) as a prominent priority contaminant in aquatic environment necessitates rigorous regulation. However, limited horizon devotes the impact of selective oxidation on the process of thallium purification. In this study, selective active radical of singlet oxygen (1O2) was continually generated for Tl(Ⅰ) oxidation accomplished with efficient Tl(Ⅲ) immobilization using iron-driven copper oxide (CuFe)/peroxymonosulfate (PMS). Fe-doping changed the active center of electronic structure for enhancing the catalytic and adsorptive reactivities, and installed magnetism for solid-liquid separation. Rapid reaction rate (0.253 min-1) coupled with vigorous elimination efficiency (98.32%) relied on electrostatic attraction, surface complexation, and H-bond interaction. EPR and XPS analyses demonstrated that the synergistic effects of ≡ Cu(Ⅰ)/≡Cu(Ⅱ) and ≡ Fe(Ⅲ)/≡Fe(Ⅱ) redounded to the sustained generation of 1O2 through the pathway of PMS → •O2- → 1O2, and 1O2 exploited an advantage to selectively oxidize Tl(Ⅰ) to Tl(Ⅲ). 3D isosurface cubic charts revealed that the immobilizing ability of Tl(Ⅲ) hydrate for CuFe was notably superior to that of Tl(Ⅲ) hydrate for CuO and Tl(Ⅰ) hydrate for CuO/CuFe, which further attested surface reactivity promoted stable immobilization form. This work develops the continuous generation of 1O2 and stable immobilization with the goal of efficiently cleansing Tl-containing wastewater.


Asunto(s)
Hierro , Oxígeno Singlete , Talio , Talio/química , Hierro/química , Oxígeno Singlete/química , Oxidación-Reducción , Cobre/química , Catálisis
2.
J Hazard Mater ; 454: 131400, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37099908

RESUMEN

The interaction between tetracycline (TTC) and mixed metallic oxides remains unclear, and even complexation usually is ignored. This study firstly distinguished the triple functions of adsorption, transformation and complexation in presence of Fe-Mn-Cu nano-composite metallic oxide (FMC) on TTC. Rapid adsorption and faint complexation initiated the transformation that dominated the entire reactions at 180 min, which completed TTC removal (up to 99.04%) synergistically within 48 h. Environmental factors (dosage, pH and coexisting ions) had small influence on TTC removal, which primarily depended on the stable transformation characteristics of FMC. Kinetic models incorporating pseudo-second-order kinetics and transformation reaction kinetics demonstrated that the surface sites of FMC promoted electron transfer process through chemical adsorption and electrostatic attraction. ProtoFit program coupled with characterization methods concluded that Cu-OH was the main reaction site of FMC where the protonated surface favored to generate·O2-. Meanwhile, three metal ions developed simultaneous mediated transformation reactions on TTC in liquid phase, and·O2- induced the production of·OH. The transformed products were subjected to toxicity assessment, which had lost antimicrobial properties toward Escherichia coli. Insights gained from this study can refine the dual mechanisms of multipurpose FMC in solid and liquid phases underlying TTC transformation.


Asunto(s)
Óxidos , Contaminantes Químicos del Agua , Antibacterianos/toxicidad , Antibacterianos/química , Tetraciclina/toxicidad , Tetraciclina/química , Iones , Adsorción , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Cinética
3.
Aging (Albany NY) ; 14(21): 8818-8838, 2022 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-36347025

RESUMEN

BACKGROUND: N6-methyladenosine (m6A) is the most abundant epigenetic modification. Although the dysregulation of m6A regulators has been associated with cancer progression in several studies, its relationship with cancer prognosis and clinicopathology is still controversial. Therefore, we evaluated the prognostic and clinicopathological value of m6A regulators in cancers by performing a comprehensive meta-analysis. METHODS: The PubMed, Cochrane Library, Web of Science, and Embase databases were searched up to April 2022. Hazard ratios were used to analyze the association between m6A with prognosis. We also analyze the relationship between m6A and clinicopathology using odds ratios. RESULTS: METTL3 overexpression predicted poor overall survival and disease-free survival in cancer patients (p < 0.001) such as gastric cancer (p < 0.001), esophageal squamous cell carcinoma (p < 0.001), oral squamous cell carcinoma (p = 0.002) and so on. Additionally, METTL3 overexpression was associated with poor pT stage (p < 0.001), pN stage (p < 0.001), TNM stage (p < 0.001), tumor size >5 cm (p < 0.001) and vascular invasion (p = 0.024). Conversely, METTL14 overexpression was positively associated with better OS (p < 0.001), negatively with poor pT stage (p = 0.001), pM stage (p = 0.002), pN stage (p = 0.011) and TNM stage (p < 0.001). Moreover, KIAA1429 overexpression was associated with poor OS (p = 0.001). YTHDF1 overexpression was also associated with advanced pM stage (p < 0.001) and tumor size >5 cm (p < 0.001). However, ALKBH5 overexpression was negatively associated with vascular invasion (p = 0.032). CONCLUSIONS: High expression of METTL3 predicted poor outcome. In contrast, high expression of METTL14 was associated with better outcome. Thus, we suggest that among all the m6A regulators, METTL3 and METTL14 could be potential prognostic markers in cancers.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias de la Boca , Humanos , Pronóstico , Metiltransferasas/genética
4.
Chemosphere ; 263: 128066, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33297071

RESUMEN

To reduce the polymerization difficulty of hydrophobic modified copolymers, a hydrophobic modified cationic flocculant was fabricated using nano-TiO2 as initiator with acrylamide (AM) and methyl acryloxyethyl dimethyl benzyl ammonium chloride (DML) as monomers, and named it PAD. The copolymers were characterized by scanning electron microscopy (SEM), nuclear magnetic resonance (1H NMR), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TG). Results verified that PAD was synthesized successfully and nano-TiO2 was more conducive to DML grafting than traditional photo-initiators. Reaction kinetics demonstrated that the polymerization process was a typical precipitation polymerization initiated by free radicals. Flocculation performance of flocculant on simulated emulsified oil was evaluated and optimized. The simulation results indicated that the flocculation performance of PAD was superior to traditional flocculant, which was attributed to the higher content of DML in PAD. The maximum removal rate of emulsified oil could reach 92.10%, and the corresponding turbidity removal rate was 93.54%. Further, the mechanism studies suggested that the removal of emulsified oil was realized by the synergistic effects of electric neutralization, demulsification, hydrophobic association and adsorption bridging. The findings of this study showed that nano-TiO2 exhibited a promising prospect in the field of polymer-initiated polymerization.


Asunto(s)
Floculación , Cinética , Polimerizacion , Espectroscopía Infrarroja por Transformada de Fourier , Titanio
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