Silica monolith aerogels with different degrees of hydrophobicity by incorporating methyltrimethoxysilane (MTMS) or trimethylethoxysilane (TMES) in standard sol-gel synthesis were prepared. Excellent properties of the aerogels, obtained with the sol-gel synthesis, were preserved with supercritical drying with CO2. The degree of the hydrophobicity of the aerogels was tested by measuring the cont...

Within the phenomenological approach a criterion for a choice of the order parameter of the superfluid phases of 3 He in aerogel in a vicinity of the transition temperature is derived. The order parameter of bulk B-phase of 3 He meets this criterion and that of the bulk A-phase doesn't. A class of order parameters of Equal Spin Pairing (ESP) type meeting the derived criterion is discussed. Orde...

This paper describes the development of a threshold type aerogel Čerenkov counter with a large sensitive area of 0.6m to be carried onboard the BESS rigidity spectrometer to detect cosmic-ray antiprotons. The design incorporates a large diffusion box containing 46 finemesh photomultipliers, with special attention being paid to achieving good performance under a magnetic field and providing suff...

in this research controlled coating of magnetite (fe3o4) nanoparticles with sio2 was investigated. the fe3o4 nanoparticles were synthesized via chemical co-precipitation and then coated by silica according to stober method. effects of tetra ethyl ortho silicate (teos) concentration and ethanol to teos on the coating thickness were investigated. x-ray powder diffraction, fourier transform infrar...

In this study, the synthesis, characterization and controlled release behavior of new Hollow Silica Nano particles (HSNPs) and Magnetic Silica Nano Particles (MSNPs) were studied. Magnetic Silica Nano particles (MSNPs), as drug delivery vehicles, were synthesized through the coating of Fe3O4 nano-crystals with silica layers. The HSNPs were obtained by removal of Fe3O4 templates with hydrochlori...

Silica-based aerogels bearing a novel aminophosphonate-containing substituent were prepared. Pd2+ and Cu2+ ions introduced into aerogel matrix to form chelated complexes with aminophosphonate moiety. Both securely retain Me2+ after supercritical drying (SCD) in CO2. In silica matrix, Pd complex is reduced metallic treatment by gaseous H2 at 120 °C. lyogel can also be upon SCD isopropanol. Pd-co...

We present data for energy dissipation factor (Q−1) over a broad temperature range at various pressures of a torsion pendulum setup used to study He confined in a 98% open silica aerogel. Values for Q−1 above Tc are temperature independent and have weak pressure dependence. Below Tc, a deliberate axial compression of the aerogel by 10% widens the range of metastability for a superfluid Equal Sp...

To identify π and K in the region of 1.0 ∼ 2.5 GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained resul...