Well dispersed very long and thin silver nanowires are synthesized using glucose as a reducing agent and silver chloride as a silver source. The wire lengths are in the range of 200 to 500 microns with an average diameter of 45–65 nm.

In a low energy (2.3 kJ) Mather-type deuterium plasma focus, neutron and x-ray emission is investigated by time integrated and time resolved detectors. CR-39 nuclear track ion detectors are employed for measuring charged particle angular distribution. Correlation of charged particles with neutron and x-ray emission is also investigated. The neutron emission profile is found to be composed of two pulses, the intensity and anisotropy of which vary with the filling pressure. The charged particle flux is maximum with high fluence anisotropy for the pressure range 2.5-3.0 mbar which is also the optimum pressure for high neutron emission with low fluence anisotropy (∼1.5). The high neutron emission with low fluence anisotropy is attributed to the presence of trapped deuterons in an anomalous magnetic field. The relevant pressure range generates favourable conditions for plasma density and pinch filament diameter. X-ray emission is generally high at low pressure. For the pressure range of 2.5-4.0 mbar, the axial neutron detector registers a hard x-ray pulse, which may escape through a half inch thick Cu flange. These results suggest that at low pressures, the collapsing current sheath interacts with the anode end and causes intense low energy (≤10 keV) x-ray emission, but the neutron emission remains low. X-rays are dominantly Cu Kα. In the narrow pressure regime 2.5-3.0 mbar, the current sheath forms a pinch filament leading to high neutron yield with low fluence anisotropy.

The x-ray emission from a low-energy (2.3 kJ) plasma focus is investigated with neon as the filling gas. Two anode configurations are used in the experiment: the conventional cylindrical anode, and tapered anode slightly toward the open end. The latter geometry enhances soft x-ray emission by an order of magnitude. The emission is pressure dependent and, in both cases, the highest emission is observed at 3-3.5 mbar. For the cylindrical anode, the soft x-ray emission is up to 7 J per shot, which is from a pinched plasma column, 5-6 mm long. For the tapered anode, up to 80 J per shot soft x-ray yield in 4π geometry is recorded, which corresponds to 4% wall plug efficiency. The diameter of the x-ray emission filament is much larger compared with the cylindrical anode. The bulk of emitted radiation is of energy 1.2-1.3 keV, which is thought to arise from recombination of hydrogen-like (Ne X) ions with the low-energy electrons.

A low-energy (2.3 kJ) plasma focus is operated in an enhanced Cu Kα line emission mode. The emission is dominated by the interaction of electrons in the current sheath with the anode tip. The Cu Kα line radiation of 0.4 J/sr is recorded in the side-on direction, which steadily increases in the end-on direction and attains the value of 0.8 J/sr. It is estimated about 40 J of energy is radiated as x rays, out of which 8 J is in the form of Cu Kα lines in 4π geometry. The radiation yield represents a system efficiency of 1.7% for overall x-ray emission, and 0.35% for the Cu Kα line.

X-radiation emission from a low-energy Mather-type plasma focus operated with argon is investigated. Attention is paid to finding the pressure range for the highest argon K-series line emission. The argon line radiation yield is highest at 1.5 mbar and the emitted energy in 4π geometry is estimated to be about 30 mJ, with a system efficiency of 0.0015%. The emission at an energy exceeding 3 keV is found to be highest at a 0.5 mbar filling pressure, giving a total yield of 0.7 J in 4π geometry, which corresponds to a device efficiency of about 0.028%. This emission is mainly due to the interaction of energetic electrons with the anode.

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