We investigate discharge inception in air, in uniform background electric fields above and below the breakdown threshold. We perform 3D particle simulations that include a natural level of background ionization in the form of positive and − O2 ions. In background fields below breakdown, we use a strongly ionized seed of electrons and positive ions to enhance the field locally. In the region of ...

We argue that the presence of dissociated ions in block copolymers under electric fields can induce strong morphological changes and even lead to phase transitions. We investigate, in particular, diblock copolymers in the body centered cubic (bcc) phase. In pure dielectric materials (no free charges), a dielectric breakdown is expected to occur for large enough electric fields, preempting any s...

The conductivity mismatch in the composite insulation of high voltage direct current (HVDC) cable accessories causes electric field distribution distortion and even insulation breakdown. Therefore, a liquid silicone rubber (LSR) filled with SiC nanoparticles is prepared for the insulation of cable accessories. The micro-morphology of the SiC/LSR nanocomposites is observed by scanning electron m...

A contactless power transfer system for charging electric vehicles requires a high efficiency, a large air gap, and a good tolerance to lateral misalignment and needs to be compact and lightweight. A double-sided winding 10 kW transformer based on a 1.5 kW H-shaped core transformer was developed for a rapid charger. Even though the transformer capacity was increased, the dimensions of the 10 kW...

Major issues of NBI power supplies are a high-speed switching, regulation and transmission of dc ultra high voltage, and suppression of surge energy input to the beam source at breakdown. A GTO(gate turn off thyristor) inverter type power supply where the control is performed at low voltage ac side was designed for the ITER NB. Based on the remarkable progress of a high power IEGT (injection en...

Three-dimensional lightning mapping observations are compared to cloud charge structures and electric potential profiles inferred from balloon soundings of electric field in New Mexico mountain thunderstorms. The comparisons consistently show good agreement between the altitudes of horizontal lightning channels and the altitudes of electric potential extrema or wells. Lightning flashes appear t...

This chapter is devoted to the analysis of electron-ionization and -elimination processes at early stages of electric-discharge development in air at altitudes of mainly 0–90 km. In this chapter, ionization processes in an external electric field, as well as background ionization by fast particles and electron attachment and detachment with participation of atomic and molecular oxygen, are cons...

Fatigue crack growth has been observed recently in ferroelectrics under cyclic electric loading[ Does the crack grow by electric breakdown\ or by the stress _eld near the crack tip< The present paper provides a mechanistic explanation for the electric!_eld!induced fatigue crack growth[ The non!uniform electric _eld near an insulated crack tip might cause domain switching which in turn produces ...

Sample preconcentration is an important step that increases the accuracy of subsequent detection, especially for samples with extremely low concentrations. Due to the overlapping of electrical double layers in the nanofluidic channel, the concentration polarization effect can be generated by applying an electric field. Therefore, a nonlinear electrokinetic flow is induced, which results in the ...