Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Soft Matter ; 18(13): 2517-2521, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35302152

RESUMO

In this paper, we have proposed a novel strategy to combine electrochemical anodization and electropolymerization for the in situ preparation of metal oxide/conductive polymer hybrid electrodes in supercapacitors. The feasibility of such a strategy was further verified by applying it to the iron oxide/polyaniline (Fe3O4/PANI) hybrid electrode material system.

2.
Langmuir ; 38(1): 164-173, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-34931850

RESUMO

In this study, electrodeposition combined with anodization was employed to prepare a nanoporous tin oxide film on a pure copper substrate. It was found that annealing temperature played a critically significant role in regulating the crystallinity, pore size, and contents of different oxidation states of the anodized tin oxide film to affect the electrochemical performance. The study verified that SnOx films treated by optimized annealing at 500 °C with precisely controlling the nanoporous morphology and crystallinity displayed competitive specific capacitance at an appropriate ratio of Sn4+ to Sn2+. A maximum specific capacitance of 86.2 mF/cm2 could be achieved at this temperature, and the capacitance retention rate still exceeded 90% even after 8000 charge-discharge cycles. With properly designed annealing treatment, we implemented tin film anodization to obtain an optimized electrode with significantly enhanced electrochemical performance, which shows a promising application in the electrochemical field to prepare electrodes.

3.
Polymers (Basel) ; 13(23)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34883723

RESUMO

This study prepared 4,4-diaminodiphenylmethane (DDM)-functionalized graphene oxide (GO)@silica dioxide (SiO2) nano-composites through amidation reaction and low-temperature precipitation. The resulting modified GO, that was DDM-GO@SiO2. The study found that DDM-GO@SiO2 showed good dispersion and compatibility with thermoplastic polyurethane (TPU) substrates. Compared with pure TPU, the tensile strength of the TPU composites increased by 41% to 94.6 MPa at only 0.5 wt% DDM-GO@SiO2. In addition, even when a small amount of DDM-GO@SiO2 was added, the UV absorption of TPU composites increased significantly, TPU composites can achieve a UV shielding efficiency of 95.21% in the UV-A region. These results show that this type of material holds great promise for the preparation of functional coatings and film materials with high strength and weather resistance.

4.
R Soc Open Sci ; 5(7): 171031, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30109033

RESUMO

Rosin esters are widely applied as masticatory substances and beverage stabilizers, while classical acid-catalysed processes will lead to metal residue or environmental issues. Super/subcritical CO2-enriched high temperature liquid water (HTLW) as a green acid catalyst in the esterification reaction of rosin with glycerol was investigated. The pH of CO2-H2O binary system, as calculated based on gas-liquid equilibrium, charge balance and chemical equilibrium equations, ranged from 3.49 to 3.70 depending on the reaction conditions, indicating effective acid catalysis. Response surface methodology experiments showed the optimum conditions were 3.5 h, 3.9 MPa CO2 pressure, a rosin-to-glycerol molar ratio of 1.32 and 269°C, and an enhanced esterification yield of 94.74% was achieved, which was superior to that obtained using a ZnO catalyst. It was found that the esterification kinetics was a pseudo first-order reaction, and the enthalpy and entropy of activation were calculated using the Arrhenius-Polanyi equation. The presence of super/subcritical CO2-enriched HTLW catalyst can decrease the activation energy and significantly accelerate the reaction rate.

5.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 30(2): 432-7, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23858775

RESUMO

Articular cartilage damage is very common in clinical practices. Due to the low self healing abilities of articular cartilage, it must be repaired or substituted by implants once natural articular cartilage is damaged. On the other hand, the various technologies currently used for healing damaged articular cartilage are little satisfactory, and rarely restore full function or return the tissue to its natively normal state. Tissue engineering technology holds great promise for the healing of damage or defects of articular cartilage. Tissue engineered articular cartilage is one of the most promising methods for repairing articular cartilage trauma and defects. In this paper, the authors review the research progress of three elements such as seed cells, growth factors and scaffolds which constitute tissue engineered articular cartilage.


Assuntos
Cartilagem Articular/lesões , Cartilagem Articular/cirurgia , Condrócitos/transplante , Engenharia Tecidual/métodos , Animais , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Osteoblastos/citologia , Alicerces Teciduais
6.
Zhongguo Gu Shang ; 26(2): 175-8, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23678772

RESUMO

Articular cartilage damage is very common in clinical practices. Due to the low self-healing abilities of articular cartilage, the repair strategies for articular cartilage such as arthroscopic lavage and debridement,osteaochondral or chondrocytes transplantation, tissue engineering and hydrogel based artificial cartilage materials are the primary technologies of repairing articular cartilage defect. In this paper,the main repair strategies for the articular cartilage damage and the advantages or disadvantages of each repair technology are summarized. The arthroscopic lavage and debridement is successful in treating the early stage of osteoarthritis. Osteochondral and chondrocytes transplantation are beneficial to treat small full thickness defects. The technology of tissue engineering becomes a new method to heal articular cartilage damage, but the major problem is the absence of bonding strength between the implants and natural defect surfaces. Hydrogel based artificial cartilage possesses similar bio-mechanical and bio-tribological performances to that of natural articular cartilage. However, both bioactivity and interfacial bonding strength between the implant and natural cartilage could be further improved. How to simultaneously optimize the mechanical and bioactive as well as biotribological properties of hydrogel based materials is a focus problem concerned.


Assuntos
Cartilagem Articular/cirurgia , Artroscopia , Fenômenos Biomecânicos , Cartilagem/transplante , Condrócitos/transplante , Desbridamento , Humanos , Engenharia Tecidual
7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 37(6): 642-8, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22772408

RESUMO

The bio-tribological properties of an artificial joint can be obviously improved by surface modification technologies. In this paper, the benefits and disadvantages of various surface modification methods-such as surface coating, plasma treatment, surface texture and surface grafting modification-are discussed. The aim of surface coating and/or plasma treatment is to improve the surface hardness of the materials, thus enhancing the wear resistance of artificial joints. However, these technologies do not effectively alleviate stress concentration of material in the short times in which artificial joints bear physiological impact load, resulting in easy fracture. Surface texture serves mainly to improve the lubrication properties through micro-concavities on the material surface for storage lubricant. Surface texturing can realize improvements in bio-tribological properties, but it does not enhance the impact resistance of the joint. Surface grafting modification is implemented mainly by grafting hydrophilic or other specific functional groups to improve the surface hydrophilicity and wetability, thus enhancing lubricating performance and reducing the coefficient of friction.


Assuntos
Artroplastia de Substituição/instrumentação , Prótese Articular , Lubrificação , Falha de Prótese , Materiais Biocompatíveis/química , Humanos , Polietilenos , Estresse Mecânico , Propriedades de Superfície , Suporte de Carga/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA