الفهرس 
PREFACEOnly 14 pages are availabe for public view
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Abstract
Egyptian Atomic Energy Authority – Plasma Focus device 1 (EAEAPF1) was redesigned in terms of its electrode system material and
dimensions, insulator shape and the energy storage bank to investigate the
best plasma focus action. The inner and the outer electrodes radii were
changed from 2 and 5 cm to become 2.25 and 4.5 cm respectively. The new
electrode system is made of brass instead of stainless-steel. The inner and outer electrodes lengths were changed from 11.2 and 13.4 cm to become 10.5 and 18 cm respectively. The insulator is changed from flat Teflon to become a Pyrex glass cylinder. The energy storage bank was totally replaced by a new one which consists of three low-inductance capacitors each of 20 nH
self-inductance and 10 μF capacitance instead of two capacitor-banks, each
consists of 20 capacitors each of 1.5 μF. In EAEA-PF1 device under
consideration, the optimum PF formation conditions are separately
investigated from the measurements of different parameters such as
maximum amplitude, area and the full width at half maximum (FWHM) of
the voltage spikes. The short-circuit test was used to measure the input
electrical parameters such as the static resistance (Re) and the static
inductance (Le) of the capacitor bank and the external circuit connections.
The plasma implosion velocity (Vz) was investigated as a function of time
and axial distance. The energy during the axial phase of PF discharge is
dissipated via four processes; magnetic energy storage, mechanical energy,
external circuit Ohmic losses and plasma Ohmic losses; each of them is
measured and the ratio of total energy dissipation which is the sum of these
four processes to the input energy to device at the end of the axial phase and
immediately before the collapse phase is detected. A simple-to-perform, home-made, four magnetic probes set technique
was employed to measure the azimuthal component of magnetic field induction, Bθ attached to PCS during the axial phase at different axial
distances, z for different radial positions, r during 1 st and 2nd half cycles of discharge current, at Vch = 12 kV and P = 0.8 Torr. Distribution profiles of total magnetic force /unit volume, Ft showed that its value at each radial position is greater during the 2nd half cycle than in the 1st one.
Finally, the results of PCS shape showed that at 1st half cycle, the PCS is
more canted than the 2nd one and due to the nature of convergence of PCS at
coaxial electrodes muzzle (during1st half cycle) just before the collapse
phase, a formation of powerful PF is detected while at 2nd half cycle a poorquality PF may occur.