Compressibility of natural and synthetic high polymers at high pressures

Anomalous compressibility effects and superconductivity of EuFe2As2 under high pressures.

The crystal structure and electrical resistance of structurally layered EuFe(2)As(2) have been studied up to 70 GPa and down to a temperature of 10 K, using a synchrotron x-ray source and designer diamond anvils. The room temperature compression of the tetragonal phase of EuFe(2)As(2) (I4/mmm) results in an increase in the a-axis length and a rapid decrease in the c-axis length with increasing ...

The compositional variation of synthetic sodic amphiboles at high and ultra-high pressures

Sodic amphiboles in high pressure and ultrahigh pressure (UHP) metamorphic rocks are complex solid solutions in the system Na2O±MgO±Al2O3±SiO2± H2O (NMASH) whose compositions vary with pressure and temperature. We conducted piston-cylinder experiments at 20±30 kbar and 700±800 °C to investigate the stability and compositional variations of sodic amphiboles, based on the reaction glaucophane ˆ 2...

Adsorption at High Pressures

Plasma interferometry at high pressures

A general formulation for the measurement of plasma density and effective collision frequency for lowly as well as highly, collisional plasmas using millimeter wave interferometry is presented. In the presence of high density and collisionality at high gas pressures where the collision frequency ~n! is of the order of both the plasma (vp) and the wave frequency of the millimeter wave ~v! (n ;v ...

Electrical conductivity of wadsleyite at high temperatures and high pressures