[BMI][PF(6)] has been supported on silica and alumina in order to study the effect of these classical oxide supports on the structure of the ionic liquid. A widespread characterization by TGA, DSC, XRD and solid NMR of thin films of [BMI][PF(6)] immobilized on these amorphous supports has evidenced a dramatic effect on the ionic liquid structure depending on the nature of the support. For the a...

An experimentally motivated model is proposed for the formation of fluid-phase templates corresponding to the porous silica skeletons of diatoms, single-cell organisms found in marine and freshwater environments. It is shown that phase-separation processes on a planar surface may give rise to a quasi-static mold that could direct the deposition of condensing silica to form complex arrays of por...

A new route was recently proposed to modify some spectroscopic properties of rare-earth ions in silica-based fibers. We had shown the incorporation of erbium ions in amorphous dielectric nanoparticles, grown in fiber preforms. Here we present the achieved stabilization of nanometric erbium-doped dielectric nanoparticles within the core of silica fibers. We present the nanoparticle dimensional c...

Silicone fluids have been extensively used in certain heart-lung machines in order to remove bubbles produced by the mechanical oxygenation of the blood. The antifoaming technique involves the passing of oxygenated blood over a filmed surface or through a mesh or sponge treated with antifoam material. This is done to prevent air emboli which might occur if bubbles were allowed to enter the circ...

A smart window is fabricated from a composite consisting of elastomeric poly(dimethylsiloxane) embedded with a thin layer of quasi-amorphous silica nanoparticles. The smart window can be switched from the initial highly transparent state to opaqueness and displays angle-independent structural color via mechanical stretching. The switchable optical property can be fully recovered after 1000 stre...

spectra. THERMAL INFRARED AND VISIBLE TO NEAR-INFRARED SPECTRAL ANALYSIS OF CHERT AND AMORPHOUS SILICA. M. L. McDowell, V. E. Hamilton, S. L. Cady, and P. Knauth. Hawai’i Institute of Geophysics and Planetology, University of Hawai’i, 1680 East-West Rd, Honolulu, HI 96822 ([email protected]), Southwest Research Institute, Boulder, CO, Portland State University, Portland, OR, Arizona State Uni...

[1] The global-scale surface type 2 unit first identified with the Mars Global Surveyor Thermal Emission Spectrometer (TES) remains enigmatic. Competing hypotheses suggest that it represents either basaltic andesite or some form of altered basalt rich in dioctahedral smectite clay minerals and/or spectrally similar amorphous silica phases. Common dioctahedral smectites contain a diagnostic feat...

A comparative study of amorphous and crystalline forms of commercial aluminum hydroxides as inhibitors of alkalisilica reactions in Portland cement mortars has been performed. It was found that at dosages of 1% to 3%, amorphous aluminum hydroxide can efficiently inhibit alkali-silica expansion of Portland cement compositions. High inhibiting activity of amorphous Al(OH)3 additives may be explai...

Amorphous silica and crystalline silicalite (MFI structure) are demonstrated to be active and environmentally benign catalysts for propionic acid ketonisation at 450-500 °C to form 3-pentanone. The silicalite is particularly efficient, and its ketonisation selectivity is increased by base modification probably through generation of silanol nests.

Diatoms are microscopic, single-celled algae that possess rigid cell walls (frustules) composed of amorphous silica. Depending on the species of diatom and the growth conditions, these frustules can display a wide range of different morphologies. It is possible to design and produce specific frustule morphologies that have potential applications in nanotechnology.