Changes in Dielectric Properties

Many dielectric studies of epoxy-amine systems have been reported. It appears that the change in dielectric properties during cure may be due to three main contributions ... 

In conclusion, we reported the investigation of inner and outer interfaces in pzt in order to quantity both the amount of effective ferroelectric polarization and change in dielectric properties. With pfm and kpfm we find a transition layer occurring at the Pt/PZT interface within... 

Salt Addition to the Microwave Medium. Addition of 3% sodium chloride to the 90/10 oil/water mixture had a significant impact on the loss of volatile acids. Data is summarized in Table III. Loss of acids was much greater in systems with added salt. The increased loss is attributed to the change in dielectric properties because of dissolved salt in the water. 

LoLal system in which charge is separated in space is called the electrical double layer and its properties are characterized by electrostatic equilibrium. An electrical double layer exists in general at any interface at which there is a change in dielectric properties. It has an important influence on the structure of the interface and on the kinetics of processes occurring there. 

Finally, the third aspect is the diffuse layer. This has traditionally been treated by the Gouy-Chapman theory. Recently, attempts have been made to develop an improved model of the diffuse layer which is analytical and considers the effects of finite ion size and change in dielectric properties. These aspects of the double layer are now considered in more detail. 

Martinsen 0G, Grimnes S, Mirtaheri P. 2000. Non-invasive measurements of post mortem changes in dielectric properties of haddock muscle—A pilot study. / Food Eng 43,189-192. 

The molecular dynamics of novel, high-dielectric-permittivity poly(vinylidene fluoride) (PVDF)/PP blends with a small amount of PP-g-MA compatibilizer was reported over a wide range of temperatures and frequencies, using DRS [71]. The results showed that the concentration of PVDF in the composites dominated the changes in dielectric properties, and that the use of PP-g-MA improved the interface interaction between PVDF and PP, resulting in an increased dielectric permittivity. 

Change in dielectric properties of a warm-hardening EP resin during ouring (curing temperature WO °C)... 

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