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1.
Small ; 20(27): e2309600, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38403846

RESUMO

Constructing a stable and robust solid electrolyte interphase (SEI) has a decisive influence on the charge/discharge kinetics of lithium-ion batteries (LIBs), especially for silicon-based anodes which generate repeated destruction and regeneration of unstable SEI films. Herein, a facile way is proposed to fabricate an artificial SEI layer composed of lithiophilic chitosan on the surface of two-dimensional siloxene, which has aroused wide attention as an advanced anode for LIBs due to its special characteristics. The optimized chitosan-modified siloxene anode exhibits an excellent reversible cyclic stability of about 672.6 mAh g-1 at a current density of 1000 mA g-1 after 200 cycles and 139.9 mAh g-1 at 6000 mA g-1 for 1200 cycles. Further investigation shows that a stable and LiF-rich SEI film is formed and can effectively adhere to the surface during cycling, redistribute lithium-ion flux, and enable a relatively homogenous lithium-ion diffusion. This work provides constructive guidance for interface engineering strategy of nano-structured silicon anodes.

2.
ACS Appl Mater Interfaces ; 16(20): 26079-26087, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38742759

RESUMO

Vanadium-based oxides, known for their high capacity and low cost, have garnered significant attention as promising cathode candidates in aqueous zinc-ion batteries. Nonetheless, their poor rate performance and limited durability in aqueous electrolytes present a challenge to the realistic implementation of vanadium-based aqueous zinc-ion batteries. Here, we synthesized nitrogen-doped V2O3@C (N-V2O3@N-C) via ammonia treatment of V2O3@C derived from vanadium-based metal-organic framework (V-MOF), aiming to achieve outstanding rate and cycling performance. The N-V2O3@N-C electrode exhibits notable in situ self-transformation into an amorphous state. Density functional theory calculations reveal that the distorted N-V2O3 structure and uneven charge distribution result in the creation of an amorphous state. As expected, Zn/N-V2O3@N-C aqueous zinc-ion batteries can achieve remarkable specific capacity (349.0 mAh g-1 at 0.1 A g-1), along with impressive rate performance, showcasing a capacity of 253.5 mAh g-1 at 5 A g-1 and exceptional durability at 5 A g-1 (96.4% after 1350 cycles). The employed induced amorphization approach offers novel perspectives for designing high-performance cathodes that exhibit both sturdy structures and extended cycling lifespans.

3.
J Colloid Interface Sci ; 676: 238-248, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39029250

RESUMO

CoFe bimetallic organic frameworks (CoFe-MOFs) with tunable morphology and electronic structure are synthesized in situ utilizing cobalt hydroxide (Co(OH)2) as a semi-sacrificial template and different anionic iron salts as modifying factors in a non-calcined synthesis method. This work defines the impact of three different anionic metallic iron salts (FeCl3, Fe(NO3)3, and Fe2(SO4)3) on the morphology of MOF materials and their resulting oxygen evolution reaction (OER) catalytic activity. Employing ferric chloride (FeCl3) as the metallic iron source, heterostructured electrocatalysts (BN-CoFe-MOF) with nanoparticles decorated nanoneedle tips are obtained, exhibiting a low overpotential (230 mV at 10 mA cm-2) and a Tafel slope of 105.6 mV dec-1 in 1.0 M KOH. It also demonstrates long time stability for at least 50 h at a current density of 10 mA cm-2. The investigation uncovers that the splendid OER activity and stability of the BN-CoFe-MOF heterojunction can be attributed to its large specific surface area, desirable mesoporous structure, superaerophobic characteristic, and high exposure of active centers. This work not only provides an efficient and cost-effective MOF based OER electrocatalyst but also serves as a valuable reference for future research on morphology control and strategies to enhance the OER activity of MOF catalysts.

4.
Int J Womens Health ; 16: 1093-1101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887592

RESUMO

Objective: To evaluate factors predictive of the success of a slow-release dinoprostone vaginal insert for cervical ripening. Methods: This retrospective study included 187 women who received dinoprostone vaginal inserts for cervical ripening. The participants were divided into two groups: the transvaginal delivery group (n = 87) and cesarean section termination group (n = 100). The correlation between the parameters present before cervical ripening with dinoprostone slow release and its success, as well as complications and adverse outcomes, was analyzed. Cesarean section predictors and area under the curve (AUC) were compared between the two Groups. Results: There were statistical differences between the two groups in body mass index (BMI), height, cervical Bishop score, cephalic position, time of medication use, and fetal head position at the time of medication use (P<0.05). The optimal thresholds for identifying cesarean section in dinoprostone vaginal insert for cervical ripening were 162.5 for height (AUC = 0.61), 10.65 cm for amniotic fluid index (AUC = 0.6), S-2.5 for cephalic position (AUC = 0.61), 5.5 for bishop score of cervix (AUC = 0.65). The height, amniotic fluid index, cephalic position, and Bishop score of the cervix were included in the same model. The AUC value of the combined model was higher than the AUC value of the single factor. Conclusion: The combined model was a better predictor of cesarean section in dinoprostone vaginal inserts for cervical ripening and labor induction. The success of cervical ripening with a dinoprostone slow-release vaginal insert can be predicted by the factors that can be recognized at admission.

5.
Chemosphere ; 355: 141799, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554876

RESUMO

Designing iron-based catalysts for Fenton-like reactions with peroxymonosulfate (PMS) as oxidants have attracted growing attentions. Herein, pyrite FeS2 supported on carbon spheres (FeS2@C) is synthesized by a facile low-temperature method. The FeS2@C/PMS system can degrade carbamazepine (CBZ) effectively in a wide pH range. Sulfate radicals (SO4·-), hydroxyl radicals (·OH), superoxide radical (O2·-), and singlet oxygen (1O2) are the responsible reactive oxygen species (ROSs) for CBZ degradation. Moreover, in the simulated fixed-bed reactor, the FeS2@C/PMS system can maintain a high CBZ removal ratio of >95% for than 8 h, exhibiting its excellent stability. The outstanding performance of FeS2@C/PMS system is attributed to the presence of carbon spheres and lattice S2-, which together promote the Fe(III)/Fe(II) redox cycle. The FeS2@C is a promising catalyst due to its facile synthesis, low cost, high efficiency, and excellent stability to activate PMS for organics degradation.


Assuntos
Carbono , Compostos Férricos , Sulfetos , Ferro , Peróxidos
6.
J Colloid Interface Sci ; 672: 688-699, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38865882

RESUMO

In this study, a series of Fe-based materials are facilely synthesized using MIL-88A and melamine as precursors. Changing the mass ratio of melamine and MIL-88A could tune the coating layers of generated zero-valent iron (Fe0) particles from Fe3C to Fe3N facilely. Compared to Fe/Fe3N@NC sample, Fe/Fe3C@NC exhibits better catalytic activity and stability to degrade carbamazepine (CBZ) with peroxymonosulfate (PMS) as oxidant. Free radical quenching tests, open-circuit potential (OCP) test and electron paramagnetic resonance spectra (EPR) prove that hydroxyl radicals (OH) and superoxide radical (O2-) are dominant reactive oxygen species (ROSs) with Fe/Fe3C@NC sample. For Fe/Fe3N@NC sample, the main ROSs are changed into sulfate radicals (SO4-) and high valent iron-oxo (Fe (IV)=O) species. In addition, the better conductivity of Fe3C is beneficial for the electron transfer from Fe0 to the Fe3C, thus could keep the activity of the surface sites and obtain better stability. DFT calculation reveals the better adsorption and activation ability of Fe3C than Fe3N. Moreover, PMS can also be adsorbed on the Fe sites of Fe3N with shorter FeO bonds and longer SO bonds than on Fe3C, the Fe (IV)=O is thus present in the Fe/Fe3N@NC/PMS system. This study provides a novel strategy for the development of highly active Fe-based materials for Fenton-like reactions and thus could promote their real application.

7.
Sci Total Environ ; 936: 173472, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38788947

RESUMO

Cadmium (Cd) is detrimental to grape growth, development, and fruit quality. Grafting is considered to be a useful method to improve plant adaptability to Cd stress in grape production. However, little information is available on how Cd stress affects grafted grapes. In this study, the effects of Cd on Shine Muscat grapes (Vitis vinifera L. cv. 'Shine Muscat') were studied under different "Cd treatments" concentrations (0, 0.2, 0.4, 0.8, 1.6, 3.2 mg kg-1) and "rootstock treatments" (SO4, 5BB, and 3309C). The results showed that low levels of Cd had hormesis effect and activated the grape antioxidant system to eliminate the ROS induced by Cd stress. The antioxidant capacity of the SM/3309C rootstock combination was stronger than that of the other two groups under low-concentration Cd stress. Moreover, the rootstock effectively sequestered a substantial amount of Cd, consequently mitigating the upward translocation of Cd to the aboveground portions. Transcriptomic and metabolomic analysis revealed several important pathways enriched in ABC transporters, flavonoid biosynthesis, Plant hormone signal transduction, phenylpropanoid biosynthesis, and glutathione metabolism under Cd stress. WGCNA analysis identified a hub gene, R2R3-MYB15, which could promote the expression of several genes (PAL, 4CL, CYP73A, ST, CHS, and COMT), and alleviate the damage caused by Cd toxicity. These findings might shed light on the mechanism of hormesis triggered by low Cd stress in grapes at the transcriptional and metabolic levels.


Assuntos
Cádmio , Vitis , Vitis/efeitos dos fármacos , Vitis/fisiologia , Vitis/genética , Cádmio/toxicidade , Poluentes do Solo/toxicidade , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Estresse Fisiológico , Transcriptoma
8.
J Colloid Interface Sci ; 677(Pt A): 800-811, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39121664

RESUMO

Zinc-air batteries, as one of the emerging areas of interest in the quest for sustainable energy solutions, are hampered by the intrinsically sluggish kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), and still suffer from the issues of low energy density. Herein, we report a MOF-on-MOF-derived electrocatalyst, FeCo@NC-II, designed to efficiently catalyze both ORR (Ehalf = 0.907 V) and OER (Ej=10 = 1.551 V) within alkaline environments, surpassing esteemed noble metal benchmarks (Pt/C and RuO2). Systematically characterizations and density functional theory (DFT) calculations reveal that the synergistic effect of iron and cobalt bimetallic and the optimized distribution of nitrogen configuration improved the charge distribution of the catalysts, which in turn optimized the adsorption / desorption of oxygenated intermediates accelerating the reaction kinetics. While the unique leaf-like core-shell morphology and excellent pore structure of the FeCo@NC-II catalyst caused the improvement of mass transfer efficiency, electrical conductivity and stability. The core and shell of the precursor constructed through the MOF-on-MOF strategy achieved the effect of 1 + 1 > 2 in mutual cooperation. Further application to zinc-air batteries (ZABs) yielded remarkable power density (212.4 mW/cm2), long cycle (more than 150 h) stability and superior energy density (∼1060 Wh/kg Zn). This work provides a methodology and an idea for the design, synthesis and optimization of advanced bifunctional electrocatalysts.

9.
J Colloid Interface Sci ; 665: 219-231, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38522161

RESUMO

Herein, a new heterogeneous CoSe2-x@NC material with abundant selenium vacancies is synthesized via an in-situ carbonization-selenization process from cobaltic metal organic framework (Co-MOF). The obtained CoSe2-x@NC has a unique electronic structure and rich active sites, which can activate peroxymonosulfate (PMS) to degrade carbamazepine (CBZ) with superior catalytic performance and stability. The quenchingexperiments and EPR test show that SO4•- is the dominant reactive oxidation species (ROSs) for CBZ degradation. Significantly, systemic electrochemical tests and theoretical calculations illustrated that the dominant role of SO4•- is attributed to the existence of abundant selenium vacancies in CoSe2-x@NC, which can adjust the density of electron cloud of the Co atoms in CoSe2-x@NC to improve the PMS adsorption and promoting the conversion of transition metallic redox pairs (Co3+/Co2+). This work provides a facile way to improve the activity and stability of CoSe2 by defect engineering in the PMS based advanced oxidation process (AOPs).

10.
Biochim Biophys Acta Mol Cell Res ; 1871(7): 119822, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39159685

RESUMO

Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by chronic ovulation dysfunction and overproduction of androgens. Women with PCOS are commonly accompanied by insulin resistance (IR), which can impair insulin sensitivity and elevate blood glucose levels. IR promotes ovarian cysts, ovulatory dysfunction, and menstrual irregularities in women patients, leading to the pathogenesis of PCOS. Secreted frizzled-related protein 4 (SFRP4), a secreted glycoprotein, exhibits significantly elevated expression levels in obese individuals with IR and PCOS. Whereas, whether it plays a role in regulating IR-induced PCOS still has yet to be understood. In this study, we respectively established in vitro IR-induced hyperandrogenism in human ovarian granular cells and in vivo IR-induced PCOS models in mice to investigate the action mechanisms of SFRP4 in modulating IR-induced PCOS. Here, we revealed that SFRP4 expression levels in both mRNA and protein were remarkably upregulated in the IR-induced hyperandrogenism with elevated testosterone in the human ovarian granulosa cell line KGN. Under normal conditions without hyperandrogenism, overexpressing SFRP4 triggered the remarkable elevation of testosterone along with the increased nuclear translocation of ß-catenin, cell apoptosis and proinflammatory cytokine IL-6. Furthermore, we found that phytopharmaceutical disruption of SFRP4 by genistein ameliorated IR-induced increase in testosterone in ovarian granular cells, and IR-induced PCOS in high-fat diet obese mice. Our study reveals that SFRP4 contributes to IR-induced PCOS by triggering ovarian granulosa cell hyperandrogenism and apoptosis through the nuclear ß-catenin/IL-6 signaling axis. Elucidating the role of SFRP4 in PCOS may provide a novel therapeutic strategy for IR-related PCOS therapy.

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