Non-thermal (low-temperature) plasma may act as an alternative approach to control superficial wound and skin infections when the effectiveness of chemical agents is weak due to natural pathogen or biofilm resistance. In this paper an atmospheric pressure plasma needle jet device which generates a cold plasma jet is used to measure the effectiveness of plasma treatment against different pathogenic bacteria and to test the individual susceptibility of pathogenic bacteria to non-thermal argon plasma. It is found that, Gram-negative bacteria were more susceptible to plasma treatment than Gram-positive bacteria. For the Gram-negative bacteria Pseudomonas aeruginosa, there were no survivors among the initial 1x108C.F.U (Colony Forming Unit) after a 40 seconds plasma treatment. The susceptibility of Gram-positive bacteria and the Gram-negative bacteria were species and strain specific. Staphylococcus aureus was the most resistant with 4.5 % survival of the initial 2x106C.F.U. after a 40 seconds plasma treatment. According to species, Staphylococcus aureus had a strain-dependent resistance with 39% and 99% reduction from 2x106C.F.U.of the five studied isolates, respectively, whereas, Escherichia coli had a lower resistance with 76% and 99% reduction after 40 seconds.
In this paper, an inexpensive, simple and well-accurate process of the generation of bimetallic silver Ag//gold Au core//shell is colloidal metal nanoparticles (MNPs). This is achieved via an atmospheric pressure non-thermal plasma glow discharge between two electrodes. One of these electrodes is a capillary tube placing over solution about (1 cm) that acts as the cathode, while the other electrode is a metal disk immersed in the solution and acts as an anode. Glow discharge process carried out at room temperature using a home-made cell with (6 KV) applied voltage and direct current (DC) about (1.8 mA) for different discharge periods. A wide range of bimetallic Ag//Au colloidal MNPs was rapidly synthesized as a result of non-thermal plas
... Show MoreIn this study, the use of non-thermal plasma theory to remove toxic gases emitted from a vehicle was experimentally investigated. A non-thermal plasma reactor was constructed in the form of a cylindrical tube made of Pyrex glass. Two stainless steel rods were placed inside the tube to generate electric discharge and plasma condition, by connecting with a high voltage power supply (up to 40 kV). The reactor was used to remove the contaminants of a 1.25-liter 4-cylinder engine at ambient conditions. Several tests have been carried out for a ranging speed from 750 to 4,500 rpm of the engine and varying voltages from 0 to 32 kV. The gases entering the reactor were examined by a gas analyzer and the gases concentration ratio
... Show MoreNewcastle disease virus (NDV) is a wide-spectrum anti-tumor agent. The oncolytic selectivity of NDV, a family of Paramyxoviridae, depends on the differential type of inducing different death pathways. This work was conducted to further understand the oncolytic effect of LaSota strain. A mouse breast cancer model (Murine mammary adenocarcinoma cell line AMN3) was used in this study. Methyl Thiazolyl Tetrazolium (MTT) viability assay tested different NDV multiplicity of infection (MOI) values on mouse mammary adenocarcinoma cells incubated for 72 hours post-infection. The IC50 values and anti-tumor activity of LaSota strain against AMN3 cell line were determined. Following Hematoxylin and Eosin Stain, we examined t
... Show MoreIn this paper the effect of nonthermal atmospheric argon plasma on the optical properties of the cadmium oxide CdO thin films prepared by chemical spray pyrolysis was studied. The prepared films were exposed to different time intervals (0, 5, 10, 15, 20) min. For every sample, the transmittance, Absorbance, absorption coefficient, energy gap, extinction coefficient and dielectric constant were studied. It is found that the transmittance and the energy gap increased with exposure time, and absorption. Absorption coefficient, extinction coefficient, dielectric constant decreased with time of exposure to the argon plasma
In this research, a type of gram negative bacteria was exposed to non-thermal plasma at a distance of (2 and 3 cm) from the plasma flow nozzle, with the use of an alternating power supply (5KHz), where exposure was made at two different voltages (4.9 and 8 kV). A negative gram of Pseudomonas aeruginosa bacteria was isolated and exposed to non-thermal plasma at different flow rates of argon gas whose value ranged from (1-5) liters/minute. The results showed that bacterial killing rate is directly proportional to distance while exposing the samples to non-thermal plasma, and the best factors by which a complete killing rate was obtained were at a distance of 2 cm with a voltage of 8 kV and a gas flow rate of 5 liters/min,
... Show MoreThis study illustrates the impact of non-thermal plasma (Cold Atmospheric Plasma CAP) on the lipids blood, the study in vivo. The lipids are (cholesterol, HDL-Cholesterol, LDL-Cholesterol and triglyceride) are tested. (FE-DBD) scheme of probe diameter 4cm is used for this purpose, and the output voltage ranged from (0-20) kV with variable frequency (0-30) kHz. The effect of non-thermal atmospheric plasma on lipids were studied with different exposure durations (20,30) sec. As a result, the longer plasma exposure duration decreases more lipids in blood.
The goal of this research is to use optical emission spectroscopy to investigate the parameters of exploding silver wire plasma. The silver discharge plasma's emission spectra were recorded and studied. For silver wire of diameter 0.4 mm and different currents 75,100, and 125A in deionized water, the plasma electron temperature ( ) was calculated by Boltzmann plot and container plasma medium temperature by thermal camera, and the electron density ( ) was computed by Stark broadening using the hydrogen (H line) at 656.279 nm With increasing current from 75 to 125 A, the electron density (ne) increased from 3.160× to 8.762× , while electron temperatures increased from 0.571 to 1.334 eV under the same conditions.
... Show MoreA low-cost reverse flow plasma system powered by argon gas pumping was built using homemade materials in this paper. The length of the resulting arc change was directly proportional to the flow rate, while using the thermal camera to examine the thermal intensity distribution and demonstrating that it is concentrated in the centre, away from the walls at various flow rates, the resulting arc's spectra were also measured. The results show that as the gas flow rate increased, so did the ambient temperature. The results show that the medium containing the arc has a maximum temperature of 34.1 ˚C at a flow rate of 14 L/min and a minimum temperature of 22.6 ˚C at a flow rate of 6 L/min.
The linear instability and nonlinear stability analyses are performed for the model of bidispersive local thermal non-equilibrium flow. The effect of local thermal non-equilibrium on the onset of convection in a bidispersive porous medium of Darcy type is investigated. The temperatures in the macropores and micropores are allowed to be different. The effects of various interaction parameters on the stability of the system are discussed. In particular, the effects of the porosity modified conductivity ratio parameters, and , with the int
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