Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Nanomaterials (Basel) ; 13(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37999298

RESUMO

Photocatalysis plays a pivotal role in environmental remediation and energy production and improving the efficiency of photocatalysts, yet enhancing its efficiency remains a challenge. Titanate has been claimed to be a very promising material amongst various photocatalysts in recent years. In this work, a novel composite photocatalyst of sodium titanate and potassium titanate was synthesized via a simple hydrothermal and molten salt calcination method. Low melting point nitrate was added in the calcination process, which helps reduce the calcination temperature. The as-prepared composite sample showed excellent photocatalytic performance compared with commercial P25 in the visible light range. According to the characterization of XRD, SEM, TEM, BET, UV-Vis, and photocatalytic property testing, the composite's photocatalytic performance results are due to the dual optimization brought about by the layered structure and composite of titanium salts forming a heterojunction. We believe that the composite has significant application potential for the use of titanate in the field of photocatalysis. Notably, this study employed well-documented synthesis methods and adhered to established protocols for experimental procedures.

2.
PLoS One ; 18(11): e0294858, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38032946

RESUMO

To better study the chloride ion migration in concrete with fly ash or ground granulated blast furnace slag under low fatigue load, a Caputo time fractional-order chloride diffusion model is developed in this paper. The model, grounded in Fick's second law with a fractional-order derivative, employs an implicit numerical method for discretization, resulting in a fractional-order numerical scheme. The stability and convergence of the scheme are rigorously proven within the paper. The model's unknown parameters are estimated using genetic algorithm with a grid method. To validate the model's effectiveness, its numerical solution is juxtaposed with experimental results from chloride erosion studies. Furthermore, the fitting efficacy of the Caputo time fractional-order numerical scheme is compared with that of the classical Fick's second law numerical scheme and analytical solution. The research findings demonstrate that the fractional-order numerical scheme can more accurately simulate the chloride concentration in concrete containing fly ash or slag. Additionally, the model shows promise in predicting the service life of fly ash or slag concrete.


Assuntos
Cloretos , Cinza de Carvão , Transporte de Íons , Sistemas Computacionais , Difusão , Halogênios
3.
Nanomaterials (Basel) ; 13(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37630957

RESUMO

All-inorganic perovskite quantum dots (CsPbX3 QDs) (X = Cl, Br, I) have the advantages of adjustable emission position, narrow emission spectrum, high fluorescence quantum efficiency (PLQY), easy preparation, and elevated defect tolerance; therefore, they are widely used in optoelectronic devices, such as solar cells, light-emitting diodes, and lasers. However, their stability still constrains their development due to their intrinsic crystal structure, ionic exchange of surface ligands, and exceptional sensitivity to environmental factors, such as light, water, oxygen, and heat. Therefore, in this paper, we investigate the stability improvement of CsPbX3 QDs and apply fabricated high-efficiency, stable perovskite QDs to solar cells to improve the performance of the cells further. In this paper, we focus on CsPbBr3 QDs with intrinsic extreme stability and optimize CsPbBr3 QDs using strategies, such as Mn+ doping, ligand regulation, and polymer encapsulation, which can improve optical properties while ensuring their stability. The test results show that the above five methods can improve the strength and luminescence performance of QDs, with the best stability achieved when PMMA encapsulates QDs with a ratio of PMMA = 2:1 and PLQY increases from 60.2% to 90.1%.

4.
Adv Healthc Mater ; 10(9): e2002143, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33694329

RESUMO

Nanoparticles, that can be enriched in the tumor microenvironment and deliver the payloads into cancer cells, are desirable carriers for theranostic agents in cancer diagnosis and treatment. However, efficient targeted delivery and enhanced endocytosis for probes and drugs in theranostics are still major challenges. Here, a nanoparticle, which is capable of charge reversal from negative to positive in response to matrix metalloproteinase 9 (MMP9) in tumor microenvironment is reported. This nanoparticle is based on a novel charge reversible amphiphilic molecule consisting of hydrophobic oleic acid, MMP9-cleavable peptide, and glutamate-rich segment (named as OMPE). The OMPE-modified cationic liposome forms an intelligent anionic nanohybrid (O-NP) with enhanced endocytosis through surface charge reversal in response to MMP9 in vitro. Successfully, O-NP nanohybrid performs preferential accumulation and enhances the endocytosis in MMP9-expressing xenografted tumors in mouse models, which improve the sensitivity of diagnosis agents and the antitumor effects of drugs in vivo by overcoming their low solubility and/or nonspecific enrichment. These results indicate that O-NP can be a promising delivery platform for cancer diagnosis and therapy.


Assuntos
Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Endocitose , Lipossomos , Metaloproteinase 9 da Matriz , Camundongos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Microambiente Tumoral
5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 2): o355, 2009 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-21581954

RESUMO

The title compound, C(14)H(13)Cl(2)NO(3), was obtained as the product of an attempted synthesis of herbicidally active compounds containing oxime ether and cyclo-hexenone groups. In the crystal structure, the mol-ecule adopts an endocyclic enol tautomeric form and the cyclo-hexene ring adopts a distorted envelope form. The oxime ether group has an E configuration, with the meth-oxy group anti to the ortho-chloro substitutent. Intra-molecular O-H⋯O and inter-molecular C-H⋯O hydrogen bonds are found in the crystal structure.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...