The longitudinal acoustic velocity in silica aerogel is presented as a function of the interstitial gas type and pressure. This was measured using air-coupled ultrasonic transducers configured for differential pulse transit time measurements. The results are interpreted in terms of the thermal relaxation of the acoustic pulse. The microscale temperature oscillations of the gas and solid phases ...

Liquid 3 He at low temperatures is an ideal substance to study because of its natural purity. The superfluid state, which appears at temperatures below 3 mK, has many unusual and exciting properties. These have extensively been studied experimentally, and the results are in many cases well understood theoretically using quasiclassical approximation. In this work we study the case that liquid 3 ...

A flexible carbon fiber aerogel with a very high surface area for supercapacitor application is reported by carbonization and chemical activation of low-cost natural cotton with KOH. The carbon fibers in the aerogel present as a twisted and tubular structure. Depending on the amount of KOH used in the activation process, the specific surface area of aerogels ranges from 1536 to 2436 m g−1, whil...

Biomass is the most plentiful and well-utilized renewable carbon resource on the earth. Direct conversion of biomass to carbon aerogel provides a promising approach to develop adsorbent materials. In the present work, the effect of presence of water during hydrothermal treatment and holding temperature during post-pyrolysis process have been investigated for the preparation of carbon aerogels (...

The equilibrium superfluid phase of He impregnated into high-porosity silica aerogels appears to be a non-equal-spin-pairing state in zero field at all pressures, which is generally assumed to be the Balian-Werthamer (BW) phase modified by the depairing effects of the aerogel structure. The nuclear magnetic susceptibility played a key role in identifying the B-phase of pure He with the BW state...

• Comprehensive review of all approaches used to assemble aerogel-fiber materials. “In situ sol-gel” and “via pre-formed aerogel” are described evaluated. Enhanced mechanical/physical properties obtained while keeping low thermal conductivity. An overview the market future research trends identified. Silica aerogels have a unique structure that makes them promising materials for variable applic...

background: silica aerogel is the nano-porous form silica which is the lightest synthetic solid material. some specific properties of this material include high surface area (1500 m2.g-1), low density (< 0.03 g.cm-3) and high porosity (%99). in this research, silica aerogel was investigated as an adsorbent of the heavy metal cations in aqueous solutions. methods: the silica aerogel was synthesi...

Introduction: Stardust returned to Earth samples from comet Wild 2. Until now most of the studies have been performed on terminal particles located at the end of the deceleration tracks. However, synchrotron X-ray fluorescence studies showed that a significant fraction of the cometary material is unevenly distributed along the tracks [1-2]. Here we present results of a transmission electron mic...

This article reports measurements of the concentration distribution of two model proteins adsorbed from aqueous solution by two different high surface area carbons, using small angle neutron and X-ray scattering (SANS and SAXS). The proteins investigated were bovine serum albumin (67 kDa), and bovine pancreatic trypsin inhibitor (BPTI), also known under the name aprotinin (6.5 kDa). The two car...

Charge flow in metals and mass flow in a neutral Fermi liquid show distinct profiles and are governed by different conservation properties. The connections between these two aspects of flow become apparent when we study the viscous flow of normal liquid 3He in the presence of aerogel. While the thermal flow is trivially affected, we predict that the resistance to mass flow shows a crossover fro...