New magnetic air-stable nanogranular Fe thin films of 10 ± 1.2 nm thickness were prepared onto silicon wafers at 150℃ under inert atmosphere by controlled Chemical Vapor Deposition (CVD) of triiron dodecacarbony...New magnetic air-stable nanogranular Fe thin films of 10 ± 1.2 nm thickness were prepared onto silicon wafers at 150℃ under inert atmosphere by controlled Chemical Vapor Deposition (CVD) of triiron dodecacarbonyl (Fe3(CO)12). These thin films, composed of sintered elemental Fe nanoparticles of 4.1 ± 0.7 nm diameter, are protected from air oxidation by a very thin carbon layer. The saturation magnetization of these thin Fe coatings was found to be close to that of bulk iron. The electrical resistivity behavior of the ferromagnetic thin films is similar to that of a semiconductor. In the present manuscript, these Fe thin coatings on Si wafers have been used as a catalyst for synthesizing crystalline carbon nanotubes (CNTs), by CVD using ethylene as a carbon precursor.展开更多
Based on Darcy-Brinkman Model, a theoretical study of laminar film condensation on a vertical tube surface with thin porous coatings was carried on. The results show the parameters of porous coatings (including conduc...Based on Darcy-Brinkman Model, a theoretical study of laminar film condensation on a vertical tube surface with thin porous coatings was carried on. The results show the parameters of porous coatings (including conductivity, porosity, permeability and coating thickness) and the surface subcooling have influence on condensation. Especially, the coating thickness is a key factor. Condensation will be considerably enhanced if the thickness is properly evaluated.展开更多
文摘New magnetic air-stable nanogranular Fe thin films of 10 ± 1.2 nm thickness were prepared onto silicon wafers at 150℃ under inert atmosphere by controlled Chemical Vapor Deposition (CVD) of triiron dodecacarbonyl (Fe3(CO)12). These thin films, composed of sintered elemental Fe nanoparticles of 4.1 ± 0.7 nm diameter, are protected from air oxidation by a very thin carbon layer. The saturation magnetization of these thin Fe coatings was found to be close to that of bulk iron. The electrical resistivity behavior of the ferromagnetic thin films is similar to that of a semiconductor. In the present manuscript, these Fe thin coatings on Si wafers have been used as a catalyst for synthesizing crystalline carbon nanotubes (CNTs), by CVD using ethylene as a carbon precursor.
文摘Based on Darcy-Brinkman Model, a theoretical study of laminar film condensation on a vertical tube surface with thin porous coatings was carried on. The results show the parameters of porous coatings (including conductivity, porosity, permeability and coating thickness) and the surface subcooling have influence on condensation. Especially, the coating thickness is a key factor. Condensation will be considerably enhanced if the thickness is properly evaluated.
