We have found a new stable spin state in the A-like phase of superfluid He confined to intrinsically anisotropic aerogel. The state can be formed by radiofrequency excitation applied while cooling through the superfluid transition temperature and its NMR properties are different from the standard A-like phase obtained in the limit of very small excitation. It is possible that this new state is ...

Titanium dioxide nano-particles were synthesized via the sol-gel method using titanium butoxide as the precursor. Acid catalyzed and aged gels were dried under air to produce xerogels and under supercritical conditions to produce aerogels. Porous particles obtained were characterized using X-ray diffraction, SEM and BET analysis. Aerogel powder was found to have more favorable properties compar...

Pore structure and connectivity determine how microstructured materials perform in applications such as catalysis, fluid storage and transport, filtering or as reactors. We report a model study on silica aerogel using a time-of-flight magnetic resonance imaging technique to characterize the flow field and explain the effects of heterogeneities in the pore structure on gas flow and dispersion wi...

Motivated by the recent prediction that uniaxially compressed aerogel can stabilize the anisotropic A phase over the isotropic B phase, we measure the pressure dependent superfluid fraction of (3)He entrained in 10% axially compressed, 98% porous aerogel. We observe that a broad region of the temperature-pressure phase diagram is occupied by the metastable A phase. The reappearance of the A pha...

Hierarchically structured carbon-silica aerogel (CSA) composites were synthesized from cheap water glass precursors and granulated activated carbon via a post-synthesis surface modification with trimethylchlorosilane (TMCS) and a low-cost ambient pressure drying procedure. The resultant CSA composites possess micro/mesoporous structure and hydrophobic surface. The adsorption and desorption perf...

0168-583X/$ see front matter 2010 Elsevier B.V. doi:10.1016/j.nimb.2010.12.035 ⇑ Corresponding author. E-mail address: [email protected] (H. Yan). We report measurements of the energy dependence of the total neutron scattering cross-section of CH4 both in bulk and confined in aerogel glass for neutron energies between 0:3 and 200 meV. Solid CH4 in phase II is an effective slow neutron moderat...

Aerogels are a special class of porous material, which have excellent physicochemical properties such as low density, high porosity, high surface area and adjustable surface chemistry. Aerogels were first prepared several decades ago, but never truly commercialized due to their high cost. Technological advancements in the production and quality of different types of aerogel cut costs down and m...

Charged particle identification at the PANDA experiment will be performed over a wide range of momenta by Čerenkov detectors. One option to identify higher momentum charged particles under small polar angles could be the use of silica aerogels as radiator. Simultaneously, an aerogel Čerenkov counter is being designed for the Kaos spectrometer at the Mainz Microtron MAMI for the discrimination b...

Phase transitions inside the pores of an aerogel are investigated by modelizing the aerogel structure by diffusion-limited cluster-cluster aggregation on a cubic lattice in a finite box and considering q-states Potts variables on the empty sites interacting via nearest-neighbours. Using a finite size scaling analysing of Monte-Carlo numerical results, it is concluded that for q = 4 the transiti...

K. Matsumoto,* J. V. Porto, L. Pollack, E. N. Smith, T. L. Ho, and J. M. Parpia Laboratory of Atomic & Solid State Physics and Materials Science Center, Cornell University, Ithaca, New York 14853 (Received 14 January 1997) We present evidence for a nonzero pressure, T ­ 0 superfluid phase transition of 3He in 98.2% open aerogel. Unlike bulk 3He which is a superfluid at T ­ 0 at all pressures (d...