A novel ZnO/Chitosan composite matrix was developed to fabricate the H2O2 biosensor. This material combined the advantages of inorganic species, ZnO, and organic polymer, chitosan. Horseradish peroxidase immobilized i...A novel ZnO/Chitosan composite matrix was developed to fabricate the H2O2 biosensor. This material combined the advantages of inorganic species, ZnO, and organic polymer, chitosan. Horseradish peroxidase immobilized in the material maintained its activity well as the usage of glutaraldehyde was avoided. The activity of enzyme was 7.9 times greater than the cross-linked enzyme. The parameters affecting the fabrication and experimental conditions of biosensors were optimized. With the aid of hydroquinone mediator, the biosensor had a fast response of less than 10 s. The linear range was 5.0×10-6 to 2.0× 10-3 mol/L with a sensitivity of 43.8 μA L/mmol. This matrix can also be used to immobilize other biomolecule.展开更多
New powder metallurgy processing routes were designed to manufacture Ag ZnO electrical contact composites. Their physical properties, electrical contact properties and microstructures were investigated. By modelling ...New powder metallurgy processing routes were designed to manufacture Ag ZnO electrical contact composites. Their physical properties, electrical contact properties and microstructures were investigated. By modelling tests, it is shown that the requirements of commercial use were met. It is proved that Ag ZnO composites could be used to substitute toxic Ag CdO on large load electrical contactors.展开更多
Mesoporous silica films embedded with Ag nanoparticles were directly synthesized by a solgel dip-coating process, combining alkyl (ethylene oxide) surfactant as temple and tetraethoxysilane as inorganic precursor. T...Mesoporous silica films embedded with Ag nanoparticles were directly synthesized by a solgel dip-coating process, combining alkyl (ethylene oxide) surfactant as temple and tetraethoxysilane as inorganic precursor. The addition of Ag^+ ion to the reaction sol was prior to the formation of films, followed by the heat treatment at 150℃ led to the creation ofAg nanoparticies. The formation ofAg nanoparticles and the change of its surface plasma resonance absorption were characterized by Uv-vis. The small angle XRD test indicated that the films had an ordered hexagonal mesoporous structure, of which the unit cell parameter was about 4.26 nm. The TEM images and EDS spectra of the samples have directly verified the presence of mono-dispersed Ag nanoparticles within the films, due to the confine effects of mesopores.展开更多
We present a new and practical approach for preparing submicro-textured silver and aluminum (Ag/Al) double-structured layers at low substrate temperatures. The surface texturing of silver and aluminum double-structu...We present a new and practical approach for preparing submicro-textured silver and aluminum (Ag/Al) double-structured layers at low substrate temperatures. The surface texturing of silver and aluminum double-structured layers was performed by increasing the deposition temperature of the Al layers to 270℃. The highly submicro-textured silver and aluminum double-structured layers were prepared by thermal evaporation on quartz glasses and their surface microstructure, light scattering properties, and thermal stability were investigated. Results showed that the highly submicro-textured Ag/Al composite films prepared at low substrate temperatures used as back reflectors not only can enhance the light scattering and have good thermal stability, but also have good adhesion properties. In addition, their fabrication is low cost and readily carried out.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grants No.20075006,29975006,20375012)the Foundation for Ph.D.Thesis Research(No.20010532008)the Foundation of Science Commission of Yunnan Province(No.2002B0033M).
文摘A novel ZnO/Chitosan composite matrix was developed to fabricate the H2O2 biosensor. This material combined the advantages of inorganic species, ZnO, and organic polymer, chitosan. Horseradish peroxidase immobilized in the material maintained its activity well as the usage of glutaraldehyde was avoided. The activity of enzyme was 7.9 times greater than the cross-linked enzyme. The parameters affecting the fabrication and experimental conditions of biosensors were optimized. With the aid of hydroquinone mediator, the biosensor had a fast response of less than 10 s. The linear range was 5.0×10-6 to 2.0× 10-3 mol/L with a sensitivity of 43.8 μA L/mmol. This matrix can also be used to immobilize other biomolecule.
文摘New powder metallurgy processing routes were designed to manufacture Ag ZnO electrical contact composites. Their physical properties, electrical contact properties and microstructures were investigated. By modelling tests, it is shown that the requirements of commercial use were met. It is proved that Ag ZnO composites could be used to substitute toxic Ag CdO on large load electrical contactors.
基金the National Natural Science Foundation of China(No.50272048)
文摘Mesoporous silica films embedded with Ag nanoparticles were directly synthesized by a solgel dip-coating process, combining alkyl (ethylene oxide) surfactant as temple and tetraethoxysilane as inorganic precursor. The addition of Ag^+ ion to the reaction sol was prior to the formation of films, followed by the heat treatment at 150℃ led to the creation ofAg nanoparticies. The formation ofAg nanoparticles and the change of its surface plasma resonance absorption were characterized by Uv-vis. The small angle XRD test indicated that the films had an ordered hexagonal mesoporous structure, of which the unit cell parameter was about 4.26 nm. The TEM images and EDS spectra of the samples have directly verified the presence of mono-dispersed Ag nanoparticles within the films, due to the confine effects of mesopores.
基金the National Natural Science Foundation of China(Grant No.60977028)the Key Project Foundation of Shanghai,China(Grant No.09JC1413800)
文摘We present a new and practical approach for preparing submicro-textured silver and aluminum (Ag/Al) double-structured layers at low substrate temperatures. The surface texturing of silver and aluminum double-structured layers was performed by increasing the deposition temperature of the Al layers to 270℃. The highly submicro-textured silver and aluminum double-structured layers were prepared by thermal evaporation on quartz glasses and their surface microstructure, light scattering properties, and thermal stability were investigated. Results showed that the highly submicro-textured Ag/Al composite films prepared at low substrate temperatures used as back reflectors not only can enhance the light scattering and have good thermal stability, but also have good adhesion properties. In addition, their fabrication is low cost and readily carried out.