نتایج جستجو برای: carbon aerogel
تعداد نتایج: 282705 فیلتر نتایج به سال:
Water extractable arabinoxylan (WEAX) aerogels were prepared by extracting the solvent from the alcogels (WEAX hydrogels with an alcohol as the solvent) with carbon dioxide under supercritical conditions. WEAX aerogels were characterized using scanning electron microscopy and adsorption and desorption nitrogen isotherms. The micrographs indicate a heterogeneous porous network structure in WEAX ...
We report the first observation of two-dimensional layer modes in both fully filled and partially filled aerogel. Using complementary high-energy resolution and high statistical precision neutron scattering instruments, and two different 87% porous aerogel samples, we show that the three-dimensional (3D) phonon-roton excitation energies and lifetimes of liquid 4He in aerogel are the same as in ...
Cellulose nanofibril (CNF) aerogels with grafted beta-cyclodextrin (β-CD) were prepared for the adsorption of phenol pollutants from water. Compared with regular wood fibers, CNF aerogel not only can immobilize more β-CDs, but also it provides higher porosity and a larger specific surface area for phenol absorption. The CNF-CD aerogel becomes mechanically robust through chemical crosslinking. I...
We report optofluidic waveguides made by filling microchannels in aerogel with water. The aerogel cladding is a nanoporous material with an extremely low refractive index of ~1.05, giving a large index step from the water core. Channels were formed by removing embedded optical fibers, which could be nonuniform or multiple. The porosity of the aerogel allowed air to be displaced from the channel...
We present a combined experimental and theoretical study of the drag force acting on a high porosity aerogel immersed in liquid (3)He and its effect on sound propagation. The drag force is characterized by the Knudsen number, which is defined as the ratio of the quasiparticle mean free path to the radius of an aerogel strand. Evidence of the Knudsen-hydrodynamic crossover is clearly demonstrate...
We have developed a Monte-Carlo simulation code for an aerogel Čerenkov Counter which is operated under a strong magnetic field such as 1.5T. This code consists of two parts: photon transportation inside aerogel tiles, and one-dimensional amplification in a fine-mesh photomultiplier tube. It simulates the output photoelectron yields as accurately as 5% with only a single free parameter. This co...
In Sandford et al. (1), we reported that organics found in samples returned by the Stardust spacecraft to Earth from Comet 81P/Wild 2 show a heterogeneous and unequilibrated distribution in both abundance and composition. Portions of the organics show similarities to those in meteorites and interplanetary dust particles (IDPs), but the entire suite of returned organics is more diverse and varie...
Introduction: Silica aerogel is an ultra-lowdensity glass foam used in collector tiles for the capture of particles in low Earth orbit [1] and, recently, for the capture of cometary particles by NASA’s Stardust mission [2]. Reliable and reproducible methods for cutting these and future collector tiles from sample return missions are necessary to enable detailed study of the captured material. T...
Photocatalysts are being extensively investigated to convert renewable solar energy into chemical energy but suffer from high costs or low efficiencies. We report on the development of highly visible-light photoactive composites of titania (TiO2) and single-wall carbon nanotubes (SWCNTs) that rapidly photodegrade methylene blue dyes under visible-light illumination in the absence of cocatalysts...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید