Silica aerogels applications

Passive heat-transfer enhancement techniques, retrofitted, 13 267 Passive mixers, in microfluidics, 26 966, 967 Passive noise detectors, 11 673 Passive nondestructive tests, 17 416, 425 Passive reactors, 17 555 Passive sensing materials, 22 706-707 Passive smart textiles, 24 625 Passive solar collection, silica aerogel application, 1 761-762 Pasta products, 26 278 Paste-extrusion process, 18 301-302 Paste forming, ceramics, 5 651 Paste inks, 14 315-316... 

Figure 4-11. Silica aerogel application as a Cherenkov counter installed in the BELLE detector as part of the B-Factory project.

The use of doped and undoped silica aerogels as multifunctional host materials for fluorescent dyes and other luminescent materials for display and imaging applications has been reported.278 Results have been presented on the PL spectra of undoped silica aerogels and aerogels doped with Er3+, rhodamine, and fluorescein.278... 

Silica aerogels, 1 753 applications, 1 760-767 physical properties of, 1 758, 761t versus xerogels, 1 758 Silica-alumina, 72.190-191 coke formation on, 5 268 poisons in representative reactions,... 

Since 1905, when Coblentz obtained the first IR spectrum, vibrational spectroscopy has become an important analytical research tool. This technique was then applied to the analysis of adsorbates on well-defined surfaces, subsequently moving towards heterogeneous reaction studies. Terenin and Kasparov (1940) made the first attempt to employ IR in adsorption studies using ammonia adsorbed on a silica aerogel containing dispersed iron. This led to a prediction by Eischens et al. from Beacon Laboratories in 1956 that the IR technique would prove to be extremely important in the study of adsorption and catalysis. For an excellent review article in IR spectroscopy, see Ryczkowski and references therein and for a more recent review with applications, see Topsoe. ... 

A detailed discussion of the properties of aerogels can be found in several recent review articles (51—55) and the references therein. This section provides a physical basis for these properties by focusing on the microstructure of an aerogel. The intent is to provide a bridge between the two previous sections, which discuss the preparative and drying parameters that affect microstructure, and the next one, which outlines the potential applications made possible by unique structural features. The emphasis is on silica aerogels because they have been the most extensively characterized. 

Typical applications of gas-coupled ultrasonic spectroscopy include the characterization of other porous materials such as rocks [120], paper [127], wood [128] and silica aerogels [129]. 

Thin film super-low dielectric constant silica aerogel is investigated for application in ultra-large-scale integrated circuits. It is believed that aerogels could more than double the computer speed [ 11J. Such thin films can be made by using TMOS based solution mixed with dimethyl sulfoxide, and dried with supercritical carbon dioxide after coating. A relative dielectric constant as low as 1.1 can be obtained. 

The extent to which silica aerogels have been modified is impressive. Here we will give a few selected examples of silica composite aerogels that have not been alluded to previously and describe how the incorporation of different components radically changes the properties (and hence applications) of silica aerogels. 

Houssam ER, Perrard A, Pierre AC (2004) Application of lipase encapsulated in silica aerogels to a transesterification reaction in hydrophobic and hydrophilic solvents bi-bi ping-pong kinetics. J Mol Catal B Enzym 30(3 ) 137-150... 

The application of PulseTA allows not only the amount of strongly adsorbed adsorbate to be determined, but also quantification of the desorption process and characterization of the adsorption strength and kind of active sites. Such an example is presented in Figure 24, depicting the adsorption of ammonia on titania-silica aerogels. 

---