Next Issue
Volume 3, December
Previous Issue
Volume 3, June
 
 

Plasma, Volume 3, Issue 3 (September 2020) – 4 articles

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Select all
Export citation of selected articles as:
13 pages, 4260 KiB  
Article
Bactericidal Properties of Copper-Tin Nanoparticles on Escherichia coli in a Liquid Environment
by Mohammad Rezayat, Morteza Saghafi Yazdi, Mohammad Talafi Noghani and Reza Ahmadi
Plasma 2020, 3(3), 153-165; https://doi.org/10.3390/plasma3030011 - 01 Sep 2020
Cited by 8 | Viewed by 3041
Abstract
In this research, copper-tin alloy nanoparticles were made by a mechanical alloying method and were examined by two well-known and common bactericidal tests, optical density, and colony-forming units count in terms of bactericidal properties. To confirm the results, two different percentages were used [...] Read more.
In this research, copper-tin alloy nanoparticles were made by a mechanical alloying method and were examined by two well-known and common bactericidal tests, optical density, and colony-forming units count in terms of bactericidal properties. To confirm the results, two different percentages were used as Sn-50Cu and Sn-83Cu, and standard amounts of these alloys were added to the Escherichia coli bacterial culture medium. The results of optical density show that with the addition of more values to the culture medium for bacteria, witnessing the destruction of bacteria, and also the results of colony counting tests can be seen that the number of colonies has decreased over time, even close to zero, which means the environment is free of bacteria. These standard values were different for both alloys; for the Sn-50Cu alloy, the maximum value was 4.5 mg, and for the Sn-83Cu alloy, it was 2.75 mg, which did not make any difference with the addition of these nanoparticles to the bacterial culture medium. Full article
Show Figures

Figure 1

36 pages, 1229 KiB  
Article
Ion Acceleration in Multi-Fluid Plasma: Including Charge Separation Induced Electric Field Effects in Supersonic Wave Layers
by Ross Burrows
Plasma 2020, 3(3), 117-152; https://doi.org/10.3390/plasma3030010 - 21 Aug 2020
Viewed by 2461
Abstract
The need to understand the process by which particles, including solar wind and coronal ions as well as pickup ions, are accelerated to high energies (ultimately to become anomalous cosmic rays) motivate a multi-fluid shock wave model which includes kinetic effects (e.g., ion [...] Read more.
The need to understand the process by which particles, including solar wind and coronal ions as well as pickup ions, are accelerated to high energies (ultimately to become anomalous cosmic rays) motivate a multi-fluid shock wave model which includes kinetic effects (e.g., ion acceleration) in an electromagnetically self-consistent framework. Particle reflection at the cross-shock potential leads to ion acceleration in the motional electric field and thus anisotropic heating and pressure in the shock layer, with important consequences for the multi-fluid dynamics. This motivates development of a multi-fluid model of solar wind electrons and ions treated as fluid, coupled self-consistently with a small population of ions (e.g., pickup ions) dynamically treated as individual particles. Consideration of both the time dependent and steady state regimes, indicate that such a multi-fluid approach is necessary for resolving the, Debye scale, particle reflecting cross-shock potential and subsequent dynamics. To study charge separation effects in narrow, supersonic wave layers we consider a reduction of the system to the steady state for cold ions and hot electrons and find two types of solitary waves inherent to the reduced two-fluid system in this limiting case. Full article
Show Figures

Figure 1

14 pages, 3902 KiB  
Article
10 kV SiC MOSFET Evaluation for Dielectric Barrier Discharge Transformerless Power Supply
by Mame Andallah Diop, Antoine Belinger and Hubert Piquet
Plasma 2020, 3(3), 103-116; https://doi.org/10.3390/plasma3030009 - 18 Aug 2020
Cited by 1 | Viewed by 3936
Abstract
At low pressure, cold plasmas are used for a wide range of applications such as coating, flow control, or microelectronics. Currently, this industry requires expensive vacuum systems which consume energy and time, and therefore it is very appealing to develop similar processes at [...] Read more.
At low pressure, cold plasmas are used for a wide range of applications such as coating, flow control, or microelectronics. Currently, this industry requires expensive vacuum systems which consume energy and time, and therefore it is very appealing to develop similar processes at atmospheric pressure. Under this condition, dielectric barrier discharge (DBD) is one of the best ways to obtain a cold plasma. The dielectric barriers naturally limit the current, and then the plasma temperature. Unfortunately, at atmospheric pressure the discharge ignition between the electrodes requires high voltage, which is generally obtained through a step-up transformer. The parasitic elements of this device exclude a smart control for the discharge. In order to overcome this default, we analyze the performance of a transformerless power supply developed with a recently released single-chip high-voltage semiconductor. The circuit uses only two high-voltage switches synthesized by means of the 10 kV SiC MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The design and implementation of the electric converter are presented and validated with experiments carried out on UV excimer DBD lamps. Then, the performances of the 10 kV SiC switches are analyzed and the relevance of this device for DBD applications is discussed. Full article
Show Figures

Figure 1

11 pages, 1474 KiB  
Article
Electrical Properties of Reversed-Polarity Ball Plasmoid Discharges
by Scott E. Dubowsky, Amber N. Rose, Nick G. Glumac and Benjamin J. McCall
Plasma 2020, 3(3), 92-102; https://doi.org/10.3390/plasma3030008 - 29 Jun 2020
Cited by 2 | Viewed by 3199
Abstract
Ball plasmoid discharges are a unique type of atmospheric-pressure plasma discharge with a lifetime on the order of a hundred milliseconds without attachment to a power source. These discharges are generated by a moderate current pulse over the surface of an aqueous electrolyte, [...] Read more.
Ball plasmoid discharges are a unique type of atmospheric-pressure plasma discharge with a lifetime on the order of a hundred milliseconds without attachment to a power source. These discharges are generated by a moderate current pulse over the surface of an aqueous electrolyte, and some consider the spherical plasmoid that results to bear some resemblance to ball lightning. This article presents the first analysis of the electrical properties of ball plasmoid discharges in a reversed-polarity configuration, i.e., with the central electrode serving as the anode rather than as the cathode. These experiments demonstrate that ball plasmoids can indeed be generated with either electrode polarity with similar observable properties. These results are contrary to what has previously been discussed in the literature and raise additional questions regarding formation mechanisms of ball plasmoids. Analysis of images and electrical measurements collected at various discharge energies show that two distinct processes occur during discharges with our circuitry and in this reversed-polarity configuration: the formation of spark channels between the anode and electrolyte, and the generation of streamers and a jet from the surface of the anode. Full article
Show Figures

Figure 1

Previous Issue
Next Issue
Back to TopTop