scholarly journals Some experiments on helium

1897 ◽  
Vol 60 (359-367) ◽  
pp. 449-453 ◽  
Keyword(s):  
Electric Discharge ◽  
Low Pressure ◽  
British Association ◽  
Green Line ◽  
Vacuum Tube ◽  
Partial Separation ◽  
Astrophysical Journal

In July of last year Professors Runge and Paschen (‘Phil Mag.,' 1895, [ii], vol. 40, pp. 297—302) announced their discovery that the spectrum of the gas from clèveite indicated the presence of two elements. They also stated that by means of a single diffusion through an asbestos plug, they had been able to effect a partial separation of the lighter constituent, which was characterised by the green glow which it gave under the influence of the electric discharge in a vacuum-tube, and which was represented in the spectrum by the series containing the green line, λ = 5015·6. Subsequently, at the meeting of the British Association at Ipswich, Professor Runge exhibited a tube containing the so-called green constituent; the colour of the glow differed strongly from that of an ordinary helium tube, but the gas contained in it was evidently at very low pressure, as phosphorescence was just commencing. Professor Runge has since acknowledged that the green effect in the helium tube may be produced by a change of pressure alone (‘Astrophysical Journal,’ January, 1896).

scholarly journals The analysis of gases after passage of electric discharge

1915 ◽  
Vol 91 (627) ◽  
pp. 180-189 ◽  
Keyword(s):  
Electric Discharge ◽  
Discharge Tube ◽  
Low Pressure ◽  
Pure Hydrogen ◽  
Rare Gases ◽  
Vacuum Tube ◽  
Solid Electrode ◽  
Electrode Glass

It has been found by Collie and Patterson that, after the passage of the electric discharge through pure hydrogen in a vacuum tube at low pressure, small quantities of helium and neon could be detected in the gas pumped out of the discharge tube. These gases were shown not to be present in the hydrogen which was let into the discharge tube. They must, then, either originate from—(i) occlusion of air in the glass or electrodes, or (ii) from the outer air during the experiment or the subsequent analysis, or (iii) be actually formed by some transmutation process due to the action of the discharge. In the latter case the seat of the effect of the discharge may be at the solid electrode, glass walls, or in the gas itself. The experiments of the above authors appear to show that:— (i) The gas did not originate from occlusion in the electrodes or glass walls, because these gave no such rare gases on solution and subsequent analysis of the gases.

The B′ 1Σu+ → X 1Σg+ and D 1Πu → X 1Σg+ band systems of molecular hydrogen

1994 ◽  
Vol 72 (11-12) ◽  
pp. 856-865 ◽  
Author(s):  
Hervé Abgrall ◽  
Evelyne Roueff ◽  
Françoise Launay ◽  
Jean-Yves Roncin
Keyword(s):  
Excited State ◽  
Spectral Line ◽  
Electric Discharge ◽  
Molecular Hydrogen ◽  
Low Pressure ◽  
Schrödinger Equations ◽  
Molecular Constants ◽  
Electronic Excited State ◽  
First Time ◽  
Line Positions

Spectral line positions and emission probabilities of the B′ 1Σu+ → X 1Σg+ and D 1Πu → X 1Σg+ band systems of molecular hydrogen have been calculated by solving a system of four coupled Schrödinger equations. A great number of rotational lines, emitted by a low-pressure electric discharge in H2, have been identified from 122 nm down to 78 nm. All the 69 bands of the B′ 1Σu+ → X 1Σg+ system and many high-J lines of 145 bands of the D 1Πu → X 1Σg+ system are reported for the first time. Improved molecular constants are derived for the (unperturbed) electronic excited state D 1Πu−.

scholarly journals The rotation of the electric arc in a radial magnetic field

1909 ◽  
Vol 82 (551) ◽  
pp. 29-42 ◽  
Keyword(s):  
Magnetic Field ◽  
Electric Discharge ◽  
Electric Arc ◽  
Quartz Tube ◽  
Radial Magnetic Field ◽  
Vacuum Tube

The following paper contains an account of a series of measurements of the velocity of motion of an electric arc in a magnetic field at right angles to its length. The experiments are similar to those made by Prof. Wilson and Mr. G. H. Martyn with the electric discharge in a vacuum tube and were suggested by Prof. Wilson. The apparatus consisted of a vertical iron rod (fig. 1, A) magnetised by two solenoids B at its ends, wound in opposite directions, so as to give a pole in the middle of the bar. With this arrangement the field round the middle of the bar is uniform and radial. The distance between the two solenoids was fixed by a quartz tube C, which also served to protect the iron rod from the heat of the arc.

scholarly journals Bakerian Lecture.—A chemically active modification of nitrogen, produced by the electric discharge

1911 ◽  
Vol 85 (577) ◽  
pp. 219-229 ◽  
Keyword(s):  
Nitric Oxide ◽  
Electric Discharge ◽  
Induction Coil ◽  
Pure Nitrogen ◽  
Vacuum Tube ◽  
Spark Gap ◽  
Band Spectra ◽  
James Dewar ◽  
A Current ◽  
Sulphuretted Hydrogen

It is known that vacuum tubes frequently show a luminosity of the contained gas after discharge is over. In a previous paper I was able to show that this effect, as it occurs in air, is of the nature of a phosphorescent combustion, and is due to the mutual reaction of nitric oxide and ozone, each formed in the discharge. In a second paper it was shown that other phosphorescent combustions can be observed in ozone, notably of sulphur, sulphuretted hydrogen, acetylene, and iodine. Some of these give continuous spectra, but the majority band spectra. In the first paper it was stated that pure nitrogen gives no afterglow whatever, and, with the simple induction coil discharge with which I was then working, this has been frequently verified since. Mr. Percival Lewis has however, described an afterglow obtained in nitrogen when a jar discharge with spark-gap is used. I had no difficulty in obtaining this glow as soon as the jar discharge was used, and have applied to its examination the method used in the former papers. This is due to Sir James Dewar, and consists in drawing a current of gas through the vacuum tube into an observing vessel, where the glow is developed, and thence into an air pump, which must be a mechanical one of good construction, driven by power. It is thus possible to examine the properties of the glowing nitrogen much more satisfactorily than can be done by intermittent examination after successive discharges.

Low-pressure electric discharge

1928 ◽  
Vol 205 (1) ◽  
pp. 103-111 ◽  
Author(s):  
C. Del Rosario
Keyword(s):  
Electric Discharge ◽  
Low Pressure
Sign in / Sign up

Export Citation Format

Share Document