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1.
Dalton Trans ; 52(46): 17524-17537, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37961750

RESUMO

Highly active Keggin-type silicotungstic acid (SiW12) with oxygen vacancy (Ov) defects was encapsulated into the magnetic floral N-doped carbon microspheres (γ-Fe2O3@NC-300) through the facile one-step air pyrolysis of the precursor comprising core-shell Fe3O4@polydopamine (Fe3O4@PDA) and SiW12 to prepare γ-Fe2O3@NC@SiW12-300. The fabricated catalysts were systematically characterized and subsequently employed for the oxidation desulfurization (ODS) of the model fuel. The magnetic floral γ-Fe2O3@NC@SiW12-300 catalyst exhibited nearly perfect catalytic activity, which under mild conditions could remove 100% amount of 4000 ppm DBT in model fuel within 20 min (0.03 g catalysts and n(H2O2)/n(S) of 2). The catalyst activity is mainly attributed to the high activity SiW12 with the Ov defect and its outstanding dispersibility in γ-Fe2O3@NC, along with the high number of exposed active sites. A selected catalyst, γ-Fe2O3@NC@SiW12-300, showed a noticeable turnover frequency (TOF) (110.07 h-1) and lower activation energy (38.79 kJ mol-1) in oxidative desulfurization (ODS) with good recyclability. HO˙ radical was found to be the active species involved in ODS as confirmed by the EPR and scavenger experiments. Additionally, the fabricated catalyst can be conveniently separated and recycled within an externally applied magnetic field.

2.
Ecotoxicol Environ Saf ; 263: 115240, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37441945

RESUMO

To reduce the consumption of oxidant and catalyst in Fenton-like reaction and to realize the reuse of catalyst, yeast supported iron nanoparticles (nZVI@SCM) was synthesized by tobacco leaf extract and applied in the heterogeneous Fenton-like degradation of aqueous methylene blue (MB) at ambient conditions. The performance of the composite was exploited in terms of catalytic activity and factors influencing MB degradation. The surface changes of nZVI@SCM before and after reaction were characterized by XPS, SEM, FT-IR and XRD. Iron leaching, primary reactive oxidizing species, and the storage stability and reusability of catalyst were also investigated. Typically, 99.7% removal of 50 mg/L MB, with a TOC removal of 97.2%, could be achieved within 10 h by 0.1 g/L nZVI@SCM coupled with 1.0 mM H2O2. The MB degradation is in good agreement with the pseudo-first-order model, and hydroxyl radicals in the bulk solution is the main reactive oxidizing species responsible for MB degradation. Based on the identified intermediates by liquid chromatography/mass spectrometry, the possible MB degradation mechanism in the nZVI@SCM/H2O2 system is discussed. The developed high-performance nZVI@SCM catalyst strategy can provide a new route in enhancing the Fenton-like degradation of organic contaminants with less consumption of catalyst and oxidant.


Assuntos
Ferro , Nanopartículas , Ferro/química , Saccharomyces cerevisiae , Peróxido de Hidrogênio/química , Azul de Metileno/química , Espectroscopia de Infravermelho com Transformada de Fourier , Oxidantes , Catálise
3.
J Funct Biomater ; 13(4)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36412884

RESUMO

The tendon-to-bone interface is a special structure connecting the tendon and bone and is crucial for mechanical load transfer between dissimilar tissues. After an injury, fibrous scar tissues replace the native tendon-to-bone interface, creating a weak spot that needs to endure extra loading, significantly decreasing the mechanical properties of the motor system. Macrophages play a critical role in tendon-bone healing and can be divided into various phenotypes, according to their inducing stimuli and function. During the early stages of tendon-bone healing, M1 macrophages are predominant, while during the later stages, M2 macrophages replace the M1 macrophages. The two macrophage phenotypes play a significant, yet distinct, role in tendon-bone healing. Growing evidence shows that regulating the macrophage phenotypes is able to promote tendon-bone healing. This review aims to summarize the impact of different macrophages on tendon-bone healing and the current immunomodulatory biomaterials for regulating macrophages, which are used to promote tendon-bone healing. Although macrophages are a promising target for tendon-bone healing, the challenges and limitations of macrophages in tendon-bone healing research are discussed, along with directions for further research.

4.
Food Res Int ; 157: 111258, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761570

RESUMO

In recent years, the increase in public awareness of sports has greatly promoted the development of the sports food industry. Sports food provides nutrition to meet the metabolic and energy needs of sports people. The nutritional components of sports food can be divided into basic nutrients and functional factors. Basic nutrients refer to the nutrients or metabolites required by the human body. Functional factors are bioactive ingredients that have potential effects in improving functions of the human body, such as protection of articular cartilage and improving muscle quality. Currently, there are various forms of sports foods in the market, including sports drinks, solid sports foods, semi-solid sports foods, and sports nutrition supplements. The sports food industry has seen many opportunities such as the expanding market, manufacturing technology development, and increasing funds investment. However, it also faces many challenges, such as lack of innovation, insufficient in-depth research, risks, and safety issues. This review would provide theoretical guidance for current sports food manufacture to meet the needs of increasing sports people worldwide.


Assuntos
Esportes , Suplementos Nutricionais , Indústria Alimentícia , Humanos , Estado Nutricional , Esportes/fisiologia
5.
Front Nutr ; 8: 765589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796195

RESUMO

Oil-in-water emulsions are widely encountered in the food and health product industries. However, the unsaturated fatty acids in emulsions are easily affected by light, oxygen, and heat, which leads to oxidation, bringing forward difficulties in controlling emulsion quality during transportation, storage, and retail. Proteins are commonly used as emulsifiers that can enhance the shelf, thermal and oxidation stability of emulsions. Polyphenols are commonly found in plants and members of the family have been reported to possess antioxidant, anticancer, and antimicrobial activities. Numerous studies have shown that binding of polyphenols to proteins can change the structure and function of the latter. In this paper, the formation of protein-polyphenol complexes (PPCs) is reviewed in relation to the latters' use as emulsifiers, using the (covalent or non-covalent) interactions between the two as a starting point. In addition, the effects polyphenol binding on the structure and function of proteins are discussed. The effects of proteins from different sources interacting with polyphenols on the emulsification, antioxidation, nutrient delivery and digestibility of oil-in-water emulsion are also summarized. In conclusion, the interaction between proteins and polyphenols in emulsions is complicated and still understudied, thereby requiring further investigation. The present review results in a critical appraisal of the relevant state-of-the-art with a focus on complexes' application potential in the food industry, including digestion and bioavailability studies.

6.
Environ Sci Pollut Res Int ; 27(15): 18831-18842, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32207021

RESUMO

In this study, 2 (3), 9 (10), 16 (17), 23 (24)-tetrakis-(8-quinoline-oxy) phthalocyanine zinc(II) (ZnQPc) was prepared and then quaternized to obtain water soluble zinc phthalocyanine (ZnQPc4+). Then, ZnQPc4+ was used as a photosensitizer for a series of POM catalysts, including Dawson type K6[α-P2W18O62]·14H2O (P2W18) and K10[α-P2W17O61]·20H2O (P2W17) and Keggine type H3PW12O40·xH2O (PW12). The Keggin type PW12 showed higher efficiency with 18.2 µmol of H2 evolution (turnover number (TON) = 14,550) for 6 h upon ZnQPc4+ sensitization in relation to two Dawson P2W17 and P2W18 in a visible light-driven water-soluble system with isopropanol and H2PtCl6·6H2O. In addition, the complexes of ZnQPc4+ with a series of POM catalysts (P2W17, P2W18, and PW12) were also used as photocatalysts for the degradation of methylene blue (MB) in water, and it was found that the complexes of ZnQPc4+ with P2W17 and PW12 showed improved photocatalytic activity, and the degradation rates of MB reached 100% at a small dosage under natural pH and visible light. The high efficacy of POM catalysts for H2 evolution and the degradation of MB were attributed to the sensitization of POMs by ZnQPc4+, which was enabled by the transfer of photogenerated electrons of ZnQPc4+ to the lowest unoccupied molecular orbital (LUMO) of POM.


Assuntos
Poluentes Ambientais , Compostos de Tungstênio , Hidrogênio , Indóis , Isoindóis
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