Aerogels are highly porous structures prepared via a sol-gel process and supercritical drying technology. Among the classes of aerogels, silica aerogel exhibits the most remarkable physical properties, possessing lower density, thermal conductivity, refractive index, and dielectric constant than any solids. Its acoustical property is such that it can absorb the sound waves reducing speed to 100 m/s compared to 332 m/s for air. However, when it comes to commercialization, the result is not as expected. It seems that mass production, particularly in the aerospace industry, has dawdled behind. This paper highlights the evolution of aerogels in general and discusses the functions and significances of silica aerogel in previous astronautical applications. Future outer-space applications have been proposed as per the current research trend. Finally, the implementation of conventional silica aerogel in aeronautics is argued with an alternative known as Maerogel.

No abstract

We synthesize porous polyHIPE networks with silanol functionalities in the polyHIPE backbone. These silanol functionalities are used for covalent bonding with silica aerogels embedded in the polyHIPE. Covalent bonding between silica and polyHIPE networks are confirmed using Fourier-transform infrared spectroscopy and scanning electron microscopy. Silica aerogels covalently bonded with polyHIPE network show macroporous and mesoporous morphologies and possess excellent properties like high bendability, high elasticity, superhydrophobicity (~160°), low density (~0.128 g/cm3), and low thermal conductivity (~0.045 W/m·K). Oil absorption from water/oil mixtures and recovery of the absorbed oil (by squeezing) from flexible silica-polyHIPE networks is studied. The silica-polyHIPE is shown to absorb crude oil ~16-times its own weight and can be reused multiple times after recovery. Hence, such materials are very important for oil spill cleanup applications from aqueous systems.

Despite the trend of leaving Facebook (#DeleteFacebook campaign), investigation on both the social and psychological factors affecting Facebook fatigue is limited. This study aims to explore the social and psychological antecedents of Facebook fatigue and identify the effects of the antecedents on overall Facebook fatigue. A total of 327 Facebook users participated in an online survey. Respondents were recruited from a major online panel in Korea. The results from the principal component analysis suggest that there are six social and psychological antecedents: impression management, unwanted posts, reputation concern, personal relative deprivation, privacy concern, and relationship concern. In addition, the results show that personal relative deprivation, privacy concern, impression management, and relationship concern positively predicted overall Facebook fatigue. This research not only sheds light on the antecedents of social networking services (SNS) fatigue that influence overall Facebook fatigue but also suggests practical implications for the everexpanding SNS market.

No abstract

No abstract

No abstract

No abstract