The influence of pre-ionization around the insulator sleeve of plasma focus, by a mesh-type β-source 28 Ni 63 on neutron emission is investigated. The experiment is conducted on two low-energy (1.15 and 0.58 kJ) Mather-type plasma focus devices. The neutron emission is found to be increased by upto 25%. The results of this experiment suggest that pre-ionization may be helpful in designing a device as a sealed neutron source for different field applications.

A study of x-ray emission from a low energy (1.8 kJ) plasma focus (PF) device powered by a 9 µF capacitor bank, charged at 20 kV and giving peak discharge current of about 175 kA by using three different anode shapes with a lead insert at the tip is reported. Quantrad Si PIN-diodes with differential filtering are employed as time-resolved x-ray detectors, whereas a multipinhole camera with suitable absorption filters is used for time-integrated analysis. The x-ray flux in different energy windows is measured as a function of the hydrogen filling pressure for each anode. The maximum values of the energy-integrated x-ray flux are found to be 1.36 ± 0.06 J sr −1 , 2.70 ± 0.11 J sr −1 and 2.17 ± 0.09 J sr −1 for a cylindrical anode with a 75˚cut at the tip, a tapered anode with a 75˚cut at the tip and a tapered anode without any cut, respectively. The maximum x-ray emission in 4π-geometry is estimated to be 17.09 ± 0.75 J, 27.91 ± 1.28 J and 27.25 ± 1.13 J with a cylindrical anode with a 75˚cut at the tip, a tapered anode with a 75˚cut at the tip and a tapered anode without any cut, respectively, and the corresponding wall plug efficiencies for x-ray generation are 0.95%, 1.55% and 1.51%. X-ray emission, presumably due to the electrons' bombardment activity at the anode tip, was dominant, which is confirmed by the pinhole images. To demonstrate the feasibility of the present PF device as a possible x-ray source for good contrast radiography, a set of experimental images is presented.

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.

In this study, we have investigated the effect of copper oxide nanoparticles (CuO-NPs) on callogenesis and regeneration of Oryza sativa L (Super Basmati, Basmati 2000, Basmati 370, and Basmati 385). In this regard, CuO-NPs have been bio-synthesized via Azadirachta indica leaf extract. Scanning electron microscope (SEM) analysis depicts average particle size of 40 ± 5 nm with highly homogenous and spherical morphology. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) have been employed to confirm the phase purity of the synthesized NPs. It is found that CuO-NPs exhibit very promising results against callus induction. It is attributed to the fact that green synthesized CuO-NPs at optimum dosage possess very supportive effects on plant growth parameters. In contrast to callogenesis, differential regeneration pattern has been observed against all of the examined O. sativa L. indigenous verities. Overall observation concludes that CuO, being one of the essential plant nutrients, has greatly tailored the nutritive properties at nano-scale.

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Films of 50 normal patients and 50 dry skulls were examined to detect lines which might stimulate a nasal fracture. These were visible on the occipito-mental view but on the lateral view any line which reaches the anterior cortex must be regarded as a fracture. The results of an analysis of 100 patients with trauma to the nasal bone are also presented. It is concluded that radiography of the nasal bone is an unnecessary examination unless requested by the E.N.T. surgeon, and this will in any case occur infrequently.

Triple Langmuir probe (TLP) diagnostic system with its necessary driving circuit is developed and successfully applies for time-resolved measurement of plasma parameters in the negative glow region of pulsating-dc discharge. This technique allows the instantaneous measurement of electron temperature [T_], electron number density [n_] as well as plasma fluctuations without any voltage or frequency sweep. In TLP configuration two probes are differentially biased and serve as a floating symmetric double probe whereas the third probe is simply floating into plasma to measure floating potential as a function of time and thus incorporates the effect of plasma fluctuations. As an example of the application to time-dependent plasmas, basic plasma parameters such as floating potential, electron temperature, and electron number density in low pressure air discharge are determined as a function of time for different fill pressure. The results demonstrate temporal evolution of plasma parameters and thus plasma generation progression for different fill pressures.

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