High-frequency alternating

Electrolytes, like electronic conductors, obey Ohm s Law, except under such extreme conditions as those involving very high voltages and/or very high-frequency alternating currents. The conductance of an electrolyte is calculated from measurements of its resistance. 

Air or oxygen is passed through an intense, high voltage (approximately 4,000-12,000 V), high-frequency alternating current field. The discharge process forms ozone ... 

Radiofrequency thermal ablation (RFTA) S. Rossi et al. (1990, 1993) were the first to introduce this procedure. Under analgosedation and local anaesthesia, an expandable, cooled-tip needle electrode is inserted per-cutaneously into the tumour with the help of US, CT or MR guidance. There are various types of probes with some differences. Due to high-frequency alternating current (480-500 kHz), the tumour tissue is gradually heated (up to max. 105 °C). A necrosis voume of 4(-5) cm in diameter can be achieved. An indication is given for 1-3 foci, each with a maximum size of 5 cm in diameter. This also applies to compromised liver func-... 

Divers are an extension of the hydrometer technique. They act as miniature hydrometers in which each diver is calibrated to a particular density. Several divers of different densities are added to the fully dispersed suspension and each will settle to a height where its density is equal to the suspension around it. A copper ring sealed in each diver interacts with an external search coil (energized by high frequency alternating current), and thus the location of the diver can be monitored. 

Skin effect - The concentration of high frequency alternating currents near the surface of a conductor. 

The determinations of R which was made using high-frequency alternating current, showed that its value was approximately 0.3 H. The polarization curves were performed using the galvanostatic pulse technique and their geometric shapes were analyzed by the NOLI method [34],... 

Kohlrausch established that electrolytic solutions obeyed Ohm s law accurately once the effect of the electrolysis products was eliminated by using high-frequency alternating current. Kjohlrausch also showed from the experimental data that the conductivity of a solution couId "Be mposed of separate contributions from each ion this is known as Kohlrausch s law of the independent migration of ions. 

Corona discharge is performed in a high-frequency alternating field (14-40 kHz) at 10 20 kV between two electrodes. The plastic surface is oxidized in a very short period (milliseconds). Plasma treatment is carried out under a moderate vacuum down to ca. 10 Pa. The advantage of this technique is the better penetration depth and the fact that it is also possible to treat shaped parts more easily. The plasma can also burn in gases (e.g., argon), whereby special effects (e.g., plasma polymerization) can be achieved. 

Polymeric films have replaced paper as the dielectric medium in capacitors for high voltage or high frequency alternating current (AC) use. The relationship for the capacitance of a parallel plate capacitor... 

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