On Calculation of the Ignition Voltage for a Back-Arc Discharge in a High-Voltage Thermionic Diode

AbstractThe process of electron instability development and propagation of a cathode electron beam and anomalous ion beam, followed by outburst of current in the initial stage of arc discharge was observed in rarefied plasma cloud of high-voltage vacuum diode. These events are consistent with the model of anomalous ion acceleration in interelectrode plasma at the spark stage of vacuum arc discharge.

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Diffuse Coplanar Surface Barrier Discharge in Nitrogen: Microdischarges Statistical Behavior

Acta Polytechnica ◽

10.14311/1731 ◽

2013 ◽

Vol 53 (2) ◽

Author(s):

Jan Cech ◽

Jana Hanusova ◽

Pavel Stahel ◽

Pavel Slavicek

Keyword(s):

High Voltage ◽

Barrier Discharge ◽

Input Voltage ◽

Half Period ◽

Surface Barrier ◽

Storage Oscilloscope ◽

Iccd Camera ◽

Ignition Voltage ◽

Surface Barrier Discharge ◽

Statistical Behavior

We studied statistical behavior of microdischarges of diffuse coplanar surface barrier discharge (DCSBD) operated in nitrogen atmosphere at two input voltage regimes. We measured spectrally unresolved discharge patterns together with discharge electrical parameters using highspeed iCCD camera and digital storage oscilloscope. External synchronization enabled us to measure the discharge pattern during positive and/or negative half-period of input high voltage in the single-shotmode of operation. The comparison of microdischarges behavior during positive, negative and both half periods of input high voltage was performed for two levels of input voltage, i.e. voltage slightly above ignition voltage and high above ignition voltage (“overvoltage”). The number of microchannels crossing discharge gap was counted and compared with number of microdischarge current peaks observed during corresponding half-period of input high voltage. The relations of those incidences was shown and discussed.

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The effect of silver nanoparticles on phytopathogenic spores of Fusarium culmorum

Canadian Journal of Microbiology ◽

10.1139/w10-012 ◽

2010 ◽

Vol 56 (3) ◽

pp. 247-253 ◽

Cited By ~ 78

Author(s):

Marek Jan Kasprowicz ◽

Magdalena Kozioł ◽

Anna Gorczyca

Keyword(s):

Silver Nanoparticles ◽

High Voltage ◽

Incubation Time ◽

Mycelial Growth ◽

Arc Discharge ◽

Fusarium Culmorum ◽

Potato Dextrose Agar ◽

Sprout Length ◽

Discharge Method ◽

Control Samples

The aim of the present experiment was to investigate the influence of silver nanoparticles on Fusarium culmorum (W.G. Smith) Sacc. (FC) spores. The silver nanoparticles were produced by the high-voltage arc discharge method. To test the effect of silver nanoparticles on FC spores, 3 parameters were tested. One of these parameters was the vegetative mycelial growth in 2 experiments. The first involved the growth of FC spores on potato dextrose agar (PDA) medium after contact with 0.12–10 ppm of silver nanoparticles, and the second the growth of spores after contact with 0.12–2.5 ppm solutions of silver, but with culturing on 3 types of media (PDA, nutrient-poor PDA, and agar) instead. The next parameter was the formation of spores after the mycelia were cultured. The last parameter was spore germination in a 2.5 ppm solution of silver nanoparticles. A significant reduction in mycelial growth was observed for spores incubated with silver nanoparticles. This relationship was dependent on the incubation time and type of growth medium, but did not depend significantly on the concentration of silver nanoparticles up to 2.5 ppm. The sporulation test showed that, relative to control samples, the number of spores formed by mycelia increased in the culture after contact with silver nanoparticles, especially on the nutrient-poor PDA medium. The 24 h incubation of FC spores with a 2.5 ppm solution of silver nanoparticles greatly reduced the number of germinating fragments and sprout length relative to the control.

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High Voltage Electric Fields Have Potential to Create New Physical Pest Control Systems

Insects ◽

10.3390/insects11070447 ◽

2020 ◽

Vol 11 (7) ◽

pp. 447 ◽

Cited By ~ 2

Author(s):

Shin-ichi Kusakari ◽

Kiyotsugu Okada ◽

Manabu Shibao ◽

Hideyoshi Toyoda

Keyword(s):

Electric Field ◽

Electric Fields ◽

Pest Control ◽

Electric Charge ◽

High Voltage ◽

Arc Discharge ◽

Control Strategies ◽

Control Measures ◽

Flying Insects ◽

Electrostatic Phenomena

An electric field is the space surrounding an electric charge, within which it is capable of exerting a perceptible force on another electric charge. Especially under high voltage, electric fields induce various electrostatic phenomena, some of which could be utilized to provide remarkable pest control measures. The main focus of the present study was to introduce an attractive force generated by a surface charge on an insulated electrified conductor, which was successfully used to construct an electric field screen that prevented airborne nuisances (spores, flying insects, pollen, and fine smoke) from entering the interiors of various facilities. Another focus was the disinclination of insects to enter the electric field, thus, giving the electric field screen the ability to repel insects. Charges accumulated on the surfaces of non-insulated conductors are mobile through discharge, based on their potential difference. Such arc discharge was strong enough to destroy insects that were exposed to it. Some precedent illustrative examples are cited to explain the principles of attraction, dielectrophoretic movement of spores, and discharge-mediated positive electrification of insects, and to discuss how electric fields are generated and used in electric field-based pest control strategies.

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High Voltage Arc Discharge

Journal of Food Science ◽

10.1111/j.1750-3841.2000.tb00620.x ◽

2000 ◽

Vol 65 ◽

pp. 80-81 ◽

Cited By ~ 7

Author(s):

Gustavo V. Barbosa-Canovas ◽

Q. Howard Zhang ◽

Merle D. Pierson ◽

Donald W. Schaffner

Keyword(s):

High Voltage ◽

Arc Discharge

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A SiPM-Based Trinal Spectral Sensor Developed for Detecting Hazardous Discharges in High-Voltage Switchgear

Journal of Sensors ◽

10.1155/2020/2068280 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Xiaobing Yu ◽

Chen Shen ◽

Yan Jing ◽

Ming Ren ◽

Haitao Wu ◽

...

Keyword(s):

High Voltage ◽

Risk Evaluation ◽

Arc Discharge ◽

Spectral Ratio ◽

Electric Discharges ◽

High Confidence ◽

Spectral Bands ◽

Regular Change ◽

Discharge Monitoring ◽

Hazard Rating

Electric discharges seriously threat the safety of high-voltage switchgear. In this paper, a spectrum-based optical method is proposed for hazardous discharge monitoring. A SiPM-based trinal spectral sensor is developed with good performances in terms of sensitivity, defect resolution, and risk evaluation. Experiments carried out on two types of artificial discharges (i.e., partial discharge and arc discharge) demonstrate that the light intensities coupled in the three spectral bands account for different proportions and the ratio among the three components generally experiences a regular change with increase in severity of discharge. The typical spectral ratio values are then acquired for hazard rating of discharge and recognition of discharge types with high confidence.

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