Dielectric properties of R2O−SiO2 glasses prepared via sol-gel

Abstract

Gels from R20-SiO 2 (R = potassium, sodium and lithium) systems with a maximum alkaline content of 5 mol % were prepared. The conductivity and the alkaline ion incorporation degree as a function of temPerature were studied by a.c. impedance spectroscopy and dielectric relaxation measurements. At low temperature (20 to 200 ° C) the major contribution to the total electric conductivity is due to water conducting species (mainly protons) which are adsorbed inside the gels. From 450°C gels start to behave as conventional glasses. The total electric conductivity and activation energy values for conduction at those high temperatures are of the same order as those for glasses prepared by direct melting.

Hydrothermal Synthesis, Crystal Structure, Solid-State NMR Spectroscopy, and Ionic Conductivity of Na5InSi4O12, a Silicate Containing a Single 12-Membered Ring

“…The departure of the semicircle in the low-frequency part is due to an electrode effect. 27 Figure 5b shows the plot of the variations of the real part conductivity as a function of frequency. As frequency increases, there are three kinds of contribution to the conductivity.…”

“…The dc resistance is the intercept of the semicircle with the Z ‘ axis of the complex plot. The departure of the semicircle in the low-frequency part is due to an electrode effect . Figure b shows the plot of the variations of the real part conductivity as a function of frequency.…”

Measurement of vibration transmitted through welded object and welding strength in ultrasonic welding

“…Therefore, many researchers have studied welding control and weld quality to reduce weld defects resulting from variations in weld strength. [20][21][22][23][24][25][26][27][28][29][30] Many techniques have been developed to evaluate weld quality, including visual inspection and post-weld batch destructive testing. However, due to cost, time, and reliability issues, these techniques have had limited success, although they have been employed in practice as a means of quality control.…”