Effect of UV treatment on the dielectric strength of BOPP capacitor film
The effect of UV treatment on dielectric breakdown strength of metallized biaxially-oriented polypropylene (BOPP) capacitor film was studied. Results from Weibull statistical analysis indicate that an optimal UV exposure level of ~3.4 J/cm2 (200-400 nm) increases the breakdown strength at 1% probability by ~20%. UV spectroscopic analysis indicates that the antioxidant in BOPP was consumed almost entirely. The results suggest that antioxidant remaining in the BOPP after processing may have an unfavorable effect on the breakdown strength of the film
Large area DC dielectric breakdown voltage measurement of BOPP and PTFE thin films
The DC dielectric breakdown strength of polytetrafluoroethylene (PTFE) thin films is not widely available. A large-area breakdown measurement on self-clearing polymer films rapidly provides extensive data sets, but presents challenges in data analysis. This research extends the large-area method used on BOPP and other polymers to PTFE thin films. Measurements obtained from the large-area method are compared to more traditional, single breakdown per sample measurements.
Correlations for mass transfer between fluidized spheres and a liquid
Abstract Data on mass transfer between the solid particles and the liquid in a fluidized bed have been analyzed. After a convenient selection, various correlations have been derived. They show that for a given fluidized system, the Sherwood number is independent on the Reynolds number.