scholarly journals Construction of a power electronic source for cold plasma generation

2019 ◽  
Vol 20 (4) ◽  
pp. 1-12 ◽  
Author(s):  
Roberto Carlos Martínez Montejano ◽  
Carlos Miguel Castillo Escandón ◽  
Víctor Esteban Espinoza López ◽  
Isaac Campos Cantón ◽  
María Guadalupe Neira Velázquez ◽  
...  
Keyword(s):  
Electric Field ◽  
Dielectric Barrier Discharge ◽  
High Voltage ◽  
High Frequency ◽  
Barrier Discharge ◽  
Strong Electric Field ◽  
Power Electronic ◽  
Dielectric Barrier ◽  
Plasma Generation ◽  
Electronic Source

This paper presents the development of a high voltage and high-frequency power electronics source, for plasma generation, at atmospheric pressure and vacuum, using helium and air as working gases. The source design consists of an inductive (L) full bridge series resonant inverter at high frequency, where the control implemented allows varying duty cycle and frequency. Plasma generation is made by high voltage with the power signal applied on two electrodes, which provides a strong electric field that excites, and thus, ionize helium particles or air particles. The power electronic source operation was tested in different plasma reactor configurations (dielectric barrier discharge, double dielectric barrier discharge, and jet type discharge). The developed power electronics source shows a correct performance and generate a strong electric field to achieve the plasma discharges desired.

scholarly journals Exploring the Potential of High-Voltage Electric Field Cold Plasma (HVCP) Using a Dielectric Barrier Discharge (DBD) as a Plasma Source on the Quality Parameters of Carrot Juice

Antibiotics ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 235 ◽  
Author(s):  
Muhammad Umair ◽  
Saqib Jabbar ◽  
Mustapha Nasiru ◽  
Tayyaba Sultana ◽  
Ahmed Senan ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Thermal Treatment ◽  
Electric Field ◽  
Dielectric Barrier Discharge ◽  
High Voltage ◽  
Cold Plasma ◽  
Barrier Discharge ◽  
Carrot Juice ◽  
Dielectric Barrier ◽  
The Impact

The main aim of the current investigation was to contemplate the impact of high-voltage electric field cold plasma (HVCP) on different quality characteristics (enzymes, microbial activities, coloring pigments, ascorbic acid, polyphenolic compounds, °Brix, acidity, and color index) of carrot juice in correlation with thermal processing. A carrot juice (250 mL) sample sealed in pre-sterilized food-grade bottles, which placed between two dielectric quartz plates for HVCP treatment. The gap between the plates was 30 mm, and a stable and uniform plasma dielectric barrier discharge (DBD) generated for 3 and 4 min at 60, 70, and 80 kV. Air was used as a working gas during the DBD-based plasma treatment. The observed rise in temperature was 2–5 °C during the HVCP treatment. A water bath was used to carry out thermal treatment (100 °C for 5 min). The maximum inactivation of enzymes and microorganisms was achieved with thermal treatment and then with HVCP treatment at 70 kV for 4 min. However, maximum retention of coloring compounds, ascorbic acid, total phenols, flavonoids, and tannins was found following HVCP (70 kV for 4 min) treatment compared to thermal treatment. The °Brix, pH, and acidity remained unchanged irrespective of treatments. These findings suggest that HVCP treatment at 70 kV for 4 min may be a good alternative to thermal treatment, and it may successfully be applied in carrot juice production, resulting in reduced enzymes, lower microbial activity, and improved bioactive compounds. The prospects of overcoming the existing conventional physical and chemical methods for sterilization make it a novel and more economical technique to maintain food’s natural nourishment, composition, appearance, structure, and freshness.

scholarly journals Discharge Regimes Transition and Characteristics Evolution of Nanosecond Pulsed Dielectric Barrier Discharge

Nanomaterials ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1381 ◽  
Author(s):  
Zhang ◽  
Yang ◽  
Wang ◽  
Jia ◽  
Yuan ◽  
...  
Keyword(s):  
Electric Field ◽  
Dielectric Barrier Discharge ◽  
Barrier Discharge ◽  
Molecular Nitrogen ◽  
Emission Spectra ◽  
Single Pulse ◽  
Surface Discharge ◽  
Initial Time ◽  
Dielectric Plate ◽  
Dielectric Barrier

Discharge regime transition in a single pulse can present the breakdown mechanism of nanosecond pulsed dielectric barrier discharge. In this paper, regime transitions between streamer, diffuse, and surface discharges in nanosecond pulsed dielectric barrier discharge are studied experimentally using high resolution temporal–spatial spectra and instantaneous exposure images. After the triggering time of 2–10 ns, discharge was initiated with a stable initial streamer channel propagation. Then, transition of streamer-diffuse modes could be presented at the time of 10–34 ns, and a surface discharge can be formed sequentially on the dielectric plate. In order to analyze the possible reason for the varying discharge regimes in a single discharge pulse, the temporal–spatial distribution of vibrational population of molecular nitrogen N2 (C3Πu, v = 0,1,2) and reduced electric field were calculated by the temporal–spatial emission spectra. It is found that at the initial time, a distorted high reduced electric field was formed near the needle electrode, which excited the initial streamer. With the initial streamer propagating to the dielectric plate, the electric field was rebuilt, which drives the transition from streamer to diffuse, and also the propagation of surface discharge.

Sign in / Sign up

Export Citation Format

Share Document