DELAYED IMPLOSION OF THE Z-PINCH IN NITROGEN

1963 ◽  
Vol 41 (10) ◽  
pp. 1547-1553
Author(s):  
F. L. Curzon ◽  
R. T. Hodgson ◽  
R. J. Churchill
Keyword(s):  
Discharge Current ◽  
Time Interval ◽  
Electrical Characteristics ◽  
Discharge Column ◽  
Minimum Diameter ◽  
Photographic Evidence ◽  
Z Pinch ◽  
Framing Camera

The paper presents the first photographic evidence of the delayed implosion of the Z-pinch in nitrogen at pressures in excess of 375 μ Hg. Two implosions are observed before the discharge column is compressed to its minimum diameter. The time interval between the two implosions is found to increase linearly with pressure.The radius of the discharge column as a function of time is measured with a framing camera and is also calculated from the electrical characteristics of the discharge. By comparing the computed and measured values of the radius of the discharge column at given pressures, it has been shown that the second implosion does not arise from a transfer of the discharge current into material near the walls of the discharge vessel, in contrast to results commonly observed in very energetic discharges.

scholarly journals Corona Discharge Properties Near Metal and Dielectric Surface

2020 ◽  
Vol 9 (3) ◽  
pp. 3662-3665
Keyword(s):  
Sulfuric Acid ◽  
Corona Discharge ◽  
Discharge Current ◽  
Ferrous Metal ◽  
Dielectric Surface ◽  
Electrical Characteristics ◽  
Corona Discharges ◽  
Industrial Gases ◽  
The Creation ◽  
Discharge Method

This following research of the properties of a coronary discharge has a serious impact on the study of metallurgy. There are a lot of cases of practical use of the corona discharge functions. An example is the creation of electrostatic precipitators for the purification of industrial gases from solid and liquid particles. Using the corona discharge method, for example, smoke is cleaned in the production of sulfuric acid, air in non-ferrous metal foundries and other harmful industries. Shape of the corona discharge made utilizing cone shaped and round and hollow terminals was examined. The most electrical characteristics of discharge of this type are decided. Corona discharges are characterized by weak currents within the extend of one microampere at voltages on the arrange of 10 kilovolts and adequately week gleam discharge. Electric fluctuations within the discharge current circuit within the extend 1 kHz-120 MHz are enlisted. To think about the oscillatory forms, there were used electric and attractive tests, signals from which were sent to the Tektronix TDS 2024B oscilloscope working within the frequency analyzer mode. The electrical tests were spoken to by metal poles 1-10 cm in length and 4-5 mm in diameter. As magnetic tests, there were used coils (diameter 2-4 mm, number of turns 70-140, wire thickness 0.1 mm) set in protective dielectric walled in areas. These tests were located at a separate of 0.5-1.0 m from the release. Possible waves in plasma are suggested to explain these oscillations.

scholarly journals Soft X-ray lasing at 519.7 Å in a Recombining Z-pinch Plasma

1997 ◽  
Vol 15 (4) ◽  
pp. 589-595 ◽  
Author(s):  
E. Eberl ◽  
T. Wagner ◽  
J. Jacoby ◽  
A. Tauschwitz ◽  
D.H.H. Hoffmann
Keyword(s):  
Discharge Current ◽  
Line Intensity ◽  
Gas Pressure ◽  
Time Resolved ◽  
X Ray ◽  
Pinch Plasma ◽  
Gain Length ◽  
Z Pinch ◽  
Time Resolved Measurements

This paper is reviewing the amplification of XUV radiation at 519.7 and 498.5 Å with a gain-length product of 2.5 and 2.2 for the 4f-3d and 4d-3p transition in an oxygen Z-pinch plasma. Time resolved measurements of the O VI (519.7 Å) transition were performed and the dependence of the line intensity on the discharge current and initial gas pressure is reported.

ELECTRONIC START-UP DEVICE FOR FEEDING AMALGAM LAMPS

2020 ◽  
pp. 52-56
Author(s):  
S. A. Mikaeva
Keyword(s):  
Discharge Current ◽  
High Accuracy ◽  
Electrical Characteristics ◽  
Phase Voltage ◽  
Operating Modes ◽  
Start Up ◽  
Cooling Devices ◽  
Sinusoidal Current

The article describes the devices of electronic start-up control apparatuses for feeding amalgam bactericidal lamps of various series. Technical and electrical characteristics are given, and single and group designs of electronic controlled starting and cooling devices are described. The types of wires in the types of connections of various designs of electronic start-up devices that supply lamps with a highly stable sinusoidal current with a frequency of 43 – 50 kHz are presented. Providing heating of the electrodes before starting the set current, “lighting” of lamps and with high accuracy supporting the discharge current of lamps with fluctuations in the phase voltage of the network from 180 to 250 V, providing all types of protection in normal and abnormal operating modes.

FRAMING CAMERA STUDIES OF THE Z-PINCH IN NITROGEN

1962 ◽  
Vol 40 (9) ◽  
pp. 1191-1207 ◽  
Author(s):  
F. L. Curzon ◽  
R. J. Churchill
Keyword(s):  
Pressure Dependence ◽  
High Speed ◽  
Dispersion Relationship ◽  
Z Pinch ◽  
Framing Camera

The Z-pinch discharge in nitrogen has been studied by means of a high-speed framing camera. Pressure dependence of pre-pinch striations and electrode effects is reported. Development of Rayleigh–Taylor instabilities after the first pinch is verified, and the dispersion relationship is evaluated for the fastest growing m = 0 mode at a pressure of 100 μ Hg.

scholarly journals A time-correlated study of the Z-pinch discharge in helium

1970 ◽  
Vol 48 (7) ◽  
pp. 884-900 ◽  
Author(s):  
K. Dimoff ◽  
S. Y. K. Tam
Keyword(s):  
Shock Wave ◽  
Shock Front ◽  
Strong Evidence ◽  
Discharge Current ◽  
Time Resolved ◽  
Maximum Current ◽  
Almost All ◽  
Z Pinch ◽  
Insight Into

The development of a miniature "gradient probe" and the successful superposition of multiple photographic recordings have produced useful insight into the action of the Z-pinch discharge in helium.A correlation of luminosity and current fronts yields strong evidence for the occurrence of a nonionizing shock wave at high initial pressures in helium discharges. The relatively nonluminous shock front is followed by overlapping regions of He I and He II radiation within the collapsing current shell. At low filling pressures these two regions coincide and radiation is emitted from almost all the gas trapped within the current shell. In all cases the zone of maximum He II emission is observed to coincide with the position of maximum current density.Synchronization of the discharge current with time-resolved spectroscopic results indicates the presence of successive pinches. They are caused by the interaction of thermal and magnetic pressures after the first collapse of the discharge.

Free double layers in mercury-arc discharges

1989 ◽  
Vol 42 (2) ◽  
pp. 321-352 ◽  
Author(s):  
Homero Santiago Maciel ◽  
J. E. Allen
Keyword(s):  
Double Layer ◽  
Discharge Current ◽  
Arc Discharge ◽  
Electrical Energy ◽  
High Energy ◽  
Double Layers ◽  
Electrostatic Energy ◽  
High Current ◽  
Discharge Column ◽  
Current Limitation

A study has been carried out of free double layers formed within the plasma volume of a low-pressure mercury-arc discharge at high current densities. The free double layer is observed to form as a visible boundary, which drifts slowly from the central section of the discharge. Current-driven instabilities are observed as the discharge current is gradually increased to a critical value, at which current limitation is observed to occur. This process, which is accompanied by high-current spikes, ceases when the free double layer becomes visible as a sharp boundary dividing the discharge column into two regions of different luminosities. The layer is observed to form in the later stages of current limitation, the onset of which occurs for a ratio of drift to thermal speed of electrons of about unity. Electrical energy is converted by the layer into kinetic energy of the charged particles. Accordingly, high-energy ions were measured by means of an electrostatic energy analyser. The multiple-sheath character of the free ‘double layer’, which is inferred from probe measurements of potential profiles, is discussed and comparisons with other space-charge structures with the same topology are made.

LIGHT SCANNING ON EXTERNAL SLEEVE DISCHARGE IN HALOGENS

1965 ◽  
Vol 43 (5) ◽  
pp. 872-882 ◽  
Author(s):  
M. Venugopalan
Keyword(s):  
Discharge Tube ◽  
Discharge Current ◽  
Applied Field ◽  
Scattered Light ◽  
Maximum Magnitude ◽  
Discharge Column ◽  
Electrode Region ◽  
High Tension ◽  
Discharge Tubes ◽  
Small Rise

It has been verified that the Joshi effect (the photovariation, enhancement +Δi, and diminution −Δi of the discharge current i) in halogen-filled discharge tubes, excited by a transformer discharge of 50-cycle potentials using external sleeve electrodes, is associated with the electrode regions and predominantly with the high-tension (HT) electrode region. The techniques of (i) partial irradiation and (ii) varying the irradiated length of the discharge column starting from either electrode were used and the Joshi effect was observed with (i) a reflection galvanometer and (ii) a cathode-ray oscillograph. The effect of scattered light from the illuminated glass side of the discharge tube and the gas or vapor reaching either electrode was minimized by increasing the spacing of the electrodes and using low gas pressures.It has also been verified that the applied field is one of the factors that determine the magnitude and sign of the Joshi effect. The maximum magnitude of +Δi was observed at the breakdown value (in the dark) of the applied field; the reversal in sign of Δi and maximum magnitude of −Δi were attained by only a small rise in the applied field above that required for the breakdown of the system in the dark.

scholarly journals Development of an all-optical framing camera and its application on the Z-pinch

2017 ◽  
Vol 25 (25) ◽  
pp. 32074 ◽  
Author(s):  
Yan Song ◽  
Bodong Peng ◽  
Hong-Xing Wang ◽  
Guzhou Song ◽  
Binkang Li ◽  
...  
Keyword(s):  
All Optical ◽  
Z Pinch ◽  
Framing Camera

scholarly journals A Comparative Study on the Electrical Characteristics of Generating Plasma by Using Different Target Sources

2018 ◽  
Vol 15 (4) ◽  
pp. 436-440 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Glow Discharge ◽  
Work Function ◽  
Discharge Current ◽  
Discharge Plasma ◽  
Glow Discharge Plasma ◽  
Electrical Characteristics ◽  
Working Pressure ◽  
Dc Power ◽  
In The Beginning ◽  
Discharge Potential

In this research, the electrical characteristics of glow discharge plasma were studied. Glow discharge plasma generated in a home-made DC magnetron sputtering system, and a DC-power supply of high voltage as input to the discharge electrodes were both utilized. The distance between two electrodes is 4cm. The gas used to produce plasma is argon gas which flows inside the chamber at a rate of 40 sccm. The influence of work function for different target materials (gold, copper, and silver), - 5cm in diameter and around 1mm thickness - different working pressures, and different applied voltages on electrical characteristics (discharge current, discharge potential, and Paschen’s curve) were studied. The results showed that the discharge current and potential increase by increasing the applied voltage ranging between 300-700 V. Discharge current increased as working pressure increased in the beginning, and then semi-stabilized (slight increase) starting from 1×100 mbar, while discharge potential decreased at the beginning as working pressure increased and then semi-stabilized at the same point at which discharge current stabilized. The Paschen’s curves were compared with each other. It was concluded that the lower breakdown voltage was associated with lower work function of the (Au, Cu, and Ag) cathode material. Breakdown voltages were (395, 398, and 420) for Ag, Cu and Au respectively.

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