In this paper, the fundamental harmonic of a Nd:YAG laser (Q-switched 1064nm wavelength, 1 Hz repetition rate and 9 ns pulse duration) has been used for the ablation of cadmium samples in air at atmospheric pressure and the generation of the cadmium plasma. The experimentally observed lines of cadmium plasma emission have been used to calculate the plasma parameters such as (electron temperature (TReR), electron density (nReR), Debye length (λRDR) and plasma frequency (ωRpR)). Line pair ratio of neutral species have been used for the electron temperature and electron density measurements. Plasma parameters were studied as a functions of laser pulse energy.
Polycrystalline ingots of cadmium telluride have been synthesized using the direct
reaction technique, by fusing initial component consisting from pure elements in
stoichiometric ratio inside quartz ampoule is evacuated 10-6 torr cadmium telluride has
been grown under temperature at (1070) oC for (16) hr. was used in this study, the phases
observed in growing CdTe compound depend on the temperature used during the growth
process. Crystallography studies to CdTe compound was determined by X-ray diffraction
technique, which it has zinc blend structure and cubic unit cell, which lattice constants is
a=6.478
oA
Search Results at the International Journal of Science and Research (IJSR)
Chemical Methodologies (CHEMM)
The calculation of the charge on an isolated dust grain immersed in plasma with different grain sizes is a challenging one, especially under moderately high plasma temperature when secondary electron emission significant. The discrete charging model is used to calculate the charges of dust grain in dusty plasma. In this model, we included the effect of grain size dependence on secondary electron emission. The results show that the secondary electron emission from the glass dust grains due to energetic electron (40eV) can lead to the small grain to be slightly more positive than the large grain. Under these conditions, the smaller and larger grains would be attracted rather than repelled, which possibly lead to enhanced coagulation rates.
... Show MoreEight patients (3 male and 5 female) were treated in this study by Endovenous Laser Ablation (EVLA); Mathematical models are proposed to estimate the applied laser power and to assess the recovery period. The estimations of the applied laser power and recovery period in these models will be depended mainly on the diameter of the incompetent vein. In addition, Excel Program was utilized to find the proposed models. A 1470 nm diode laser up to 15W continuous power (CW) was used in the treatment of venous ulcers by EVLA procedure. Following up by duplex ultrasound was started in the 1st week after the first session until the vein is completely closed. The present study concluded that the relationship both between
... Show MoreIn this research, a non-thermal plasma system was designed and a non-thermal plasma needle was manufactured for argon gas operating at normal atmospheric pressure. The electrical description of this system studied by using two different values of voltages (4.9,8) kV. Where the results showed the small amount of electrical current consumed by the system of plasma needle up to several microns of amps, and the value of the electrical current increase with the increasing gas flow, as well as the results, showed that happen a breakdown voltage at (8) kV when gas flow (4 l/min) causing a slight decrease in the electrical current value.
Cold plasma is a relatively low temperature gas, so this feature enables us to use cold plasma to treat thermally sensitive materials including polymers and biologic tissues. In this research, the non-thermal plasma system is designed with diameter (3 mm, 10 mm) Argon at atmospheric pressure as well as to be suitable for use in medical and biotechnological applications.
The thermal description of this system was studied and we observed the effect of the diameter of the plasma needle on the plasma, when the plasma needle slot is increased the plasma temperature decrease, as well as the effect of the voltages applied to the temperature of the plasma, where the temperature increasing with increasing the applied voltage . Results showed t
Shisha smoke represents one of the causes of indoor air pollution. Heavy metals represent the main components in shisha smoke. In this research study, the indoor concentrations of heavy metals in shisha smoke café sites was investigated, samples were taken from two café sites (site1, site 2) which differ in their volume. Site1 volume was 77m3, while site 2 was 437.5m3. Sample were taken by using a low volume sampler (sniffer), and then examined by the Atomic Absorption Spectrometry (AAS). The results showed that indoor air shisha smoke samples for both experimental sites have shown a significant amount of heavy metals as compared with control sampling values. The mean concentration values of (Pb, Zn, Co, Ni, Cr) in site 1 were (11.004,
... Show MoreWhen employing shorter (sub picosecond) laser pulses, in ablation kinetics the features appear which can no longer be described in the context of the conventional thermal model. Meanwhile, the ablation of materials with the aid of ultra-short (sub picosecond) laser pulses is applied for micromechanical processing. Physical mechanisms and theoretical models of laser ablation are discussed. Typical associated phenomena are qualitatively regarded and methods for studying them quantitatively are considered. Calculated results relevant to ablation kinetics for a number of substances are presented and compared with experimental data. Ultra-short laser ablation with two-temperature model was quantitatively investigated. A two-temperature model
... Show MoreThe effect of different doses (75,100,150 ppm) and periods of
treatment (3,6,9 days) on the spermatognic cells in white mice was studied. It was found that there was a significant decrease (P<0.05) in the percentage of spermatogonia specially in concentration 1 00 and
150 ppm lasted six and nine days and of primary spermatocytes at period of nine days. A significant decrease (P<0.05) was noticed in the percentages of secondary spermatoytes and spermatids, while the percentage of sperms illustrated a significant increase for all concentrations and treatment periods.