This study investigated several approaches for silane-removal from the surface of short carbon fiber bundles, and short carbon fibers uniformly dispersed in cement to produce a novel compound of carbon-fiber-reinforced cement. In order to facilitate the uniform distribution of short carbon fibers in the carbon-fiber-reinforced cement, it is necessary to remove the silane from the carbon fiber’s surface. Short carbon fiber bundles were submerged into a pure water, sodium hydroxide solution, and acetic acid solution, and placed in high-temperature furnace used to remove silane from the carbon fiber surface. The results were observed under a scanning electron microscope to determine the level of silane removal from the surface, and an effective method for removing the silane was developed from among the several approaches. This method employed a pneumatic dispersion device to disperse carbon fibers then mixed in a high-early-strength cement which led to an excellent compressive and impact-resistance performance of carbon-fiber-reinforced cement. Final testing showed that the compressive strength and impact energy increased by 14.1% and 145%, respectively.
A porous-Al0.47GaN/n-Al0.47GaN stack structure
with a large refractive index contrast has been fabricated through
a homoepitaxial growth process on a Si-doped n+-Al0.47GaN/n-Al0.47GaN stack structure with a simple
electrochemical wet etching process. A 20-pairs porous-Al0.47GaN distributed Bragg reflector structure (DBR) with a high aluminum
content was fabricated at the deep-ultraviolet wavelength region of
light emitting diodes. Low compressive strain and high reflectance
has been observed in a porous-AlGaN/n-AlGaN DBR structure with 93%
reflectivity at 276 nm. The high reflectance spectrum was measured
at the 265 to 287 nm wavelength region in the porous AlGaN DBR structure.
The absorption wavelength of the AlGaN layer was observed at about
250 nm, which is shorter than the high reflectance wavelength region
of the porous DBR. Light extraction efficiency of the deep-UV optoelectronic
devices can be improved by integrating the embedded porous AlGaN reflectors
during the epitaxial growth process.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.