scholarly journals Recombination and the long duration of the Balmer spectrum

1946 ◽  
Vol 186 (1005) ◽  
pp. 236-241 ◽  
Keyword(s):  
Electric Field ◽  
Experimental Conditions ◽  
Balmer Series ◽  
Electrodeless Discharge ◽  
Long Duration

Lord Rayleigh has recently found that the time of relaxation of the Balmer series of hydrogen excited by an electrodeless discharge is at least of the order 10 -5 sec. after it has been blown out of the electric field by its own expansion. Following Page, it is assumed that the luminosity is due to recombination of electrons with protons, and then Kramers’s theory yields halfvalue periods certainly larger than 10 -5 sec. under the special experimental conditions. Difficulties in the application of this theory raised by Cillié and Page are briefly discussed.

scholarly journals Long duration of the Balmer spectrum in excited hydrogen

1944 ◽  
Vol 183 (992) ◽  
pp. 26-32 ◽  
Keyword(s):  
Hydrogen Atom ◽  
Electric Field ◽  
Balmer Series ◽  
Long Duration

The light of a condenser discharge through hydrogen, emitting the Balmer series of lines, persists for much longer than current theories and experimental determinations of the time of relaxation of the hydrogen atom would lead one to anticipate. These determinations indicate a time of the order of 10 -8 sec. for the intensity to diminish in the ratio e : 1. It is shown in the present paper that in fact, if hydrogen made luminous by a powerful discharge is blown out of the electric field by its own expansion, the time in question is under some conditions a thousand times more. The discrepancy is not cleared up, but the aim has been to present the evidence as clearly as possible for criticism.

scholarly journals Three different types of electric field disturbances affecting equatorial ionosphere during a long‐duration prompt penetration event

2015 ◽  
Vol 120 (6) ◽  
pp. 4993-5008 ◽  
Author(s):  
D. Chakrabarty ◽  
Diptiranjan Rout ◽  
R. Sekar ◽  
R. Narayanan ◽  
G. D. Reeves ◽  
...  
Keyword(s):  
Electric Field ◽  
Equatorial Ionosphere ◽  
Long Duration ◽  
Different Types

scholarly journals Homeopathic Potencies May Possess an Electric Field(-like) Component: Evidence from the Use of Encapsulated Solvatochromic Dyes

Homeopathy ◽  
2019 ◽  
Vol 109 (01) ◽  
pp. 014-022
Author(s):  
Steven J. Cartwright
Keyword(s):  
Electric Field ◽  
Bathochromic Shift ◽  
Visible Region ◽  
Electromagnetic Spectrum ◽  
Experimental Conditions ◽  
Fundamental Identity ◽  
Spectral Changes ◽  
Absorbance Change ◽  
Solvatochromic Dyes ◽  
Brooker’S Merocyanine

Background Homeopathic potencies have been shown to interact with a range of solvatochromic dyes to produce spectroscopic changes in the visible region of the electromagnetic spectrum. Furthermore, the nature of the changes observed under different experimental conditions is beginning to limit the number of possible hypotheses that can be put forward regarding the fundamental identity of potencies. Aims and Methods The present study uses β-cyclodextrins to encapsulate solvatochromic dyes of widely varying structures. The purpose of this approach is to de-couple the primary dye–potency interaction from any subsequent aggregation effects. Results Despite large differences in molecular structure between dyes, results show that potencies affect all dyes according to the same fundamental principles. Specifically, positively and negatively solvatochromic dyes collectively respond in opposite and complementary ways to potencies in accordance with the differential stabilisation of their excited and ground electronic states. Under the conditions of encapsulation, positively solvatochromic dyes display a bathochromic shift of, on average, 0.4 nm with a 2% absorbance change, and negatively solvatochromic dyes display a hypsochromic shift of, on average, 0.2 nm with a 1% absorbance change. This behaviour is only ever seen in two situations—where solvent becomes more polar or where an electric field is applied to solutions of dyes. Conclusions The conditions used in this and previous studies to investigate the interaction of potencies with solvatochromic dyes preclude increased polarity of solvent as being responsible for the observed effects and that an explanation in which potencies carry an electric field (or electric field-like) component is by far the more likely. From the magnitude of the spectral changes induced in the dye Brooker's merocyanine by Arsenicum 10M, an estimate of the strength of the postulated electric field of 1.16 × 107 V/m can be made, which is comparable with the potential difference across cell membranes.

scholarly journals The stark effect of the fine-structure of hydrogen

1928 ◽  
Vol 119 (782) ◽  
pp. 313-334 ◽  
Keyword(s):  
Fine Structure ◽  
Hydrogen Atom ◽  
Electric Field ◽  
Quantum Dynamics ◽  
Stark Effect ◽  
Energy Levels ◽  
Structure Theory ◽  
Weak Electric Field ◽  
Classical Dynamics ◽  
Balmer Series

One of the earliest successes of classical quantum dynamics in a field where ordinary methods had proved inadequate was the solution, by Schwarzschild and Epstein, of the problem of the hydrogen atom in an electric field. It was shown by them that under the influence of the electric field each of the energy levels in which the unperturbed atom can exist on Bohr’s original theory breaks up into a number of equidistant levels whose separation is proportional to the strength of the field. Consequently, each of the Balmer lines splits into a number of components with separations which are integral multiples of the smallest separation. The substitution of the dynamics of special relativity for classical dynamics in the problem of the unperturbed hydrogen atom led Sommerfeld to his well-known theory of the fine-structure of the levels; thus, in the absence of external fields, the state n = 1 ( n = 2 in the old notation) is found to consist of two levels very close together, and n = 2 of three, so that the line H α of the Balmer series, which arises from a transition between these states, has six fine-structure components, of which three, however, are found to have zero intensity. The theory of the Stark effect given by Schwarzschild and Epstein is adequate provided that the electric separation is so much larger than the fine-structure separation of the unperturbed levels that the latter may be regarded as single; but in weak fields, when this is no longer so, a supplementary investigation becomes necessary. This was carried out by Kramers, who showed, on the basis of Sommerfeld’s original fine-structure theory, that the first effect of a weak electric field is to split each fine-structure level into several, the separation being in all cases proportional to the square of the field so long as this is small. When the field is so large that the fine-structure is negligible in comparison with the electric separation, the latter becomes proportional to the first power of the field, in agreement with Schwarzschild and Epstein. The behaviour of a line arising from a transition between two quantum states will be similar; each of the fine-structure components will first be split into several, with a separation proportional to the square of the field; as the field increases the separations increase, and the components begin to perturb each other in a way which leads ultimately to the ordinary Stark effect.

A new local feedback model of the saccadic burst generator

1988 ◽  
Vol 59 (5) ◽  
pp. 1455-1475 ◽  
Author(s):  
C. A. Scudder
Keyword(s):  
Target Position ◽  
Burst Frequency ◽  
Experimental Conditions ◽  
Burst Neurons ◽  
Feedback Model ◽  
Long Duration ◽  
Important Input ◽  
Local Feedback ◽  
The Brain ◽  
Omnipause Neurons

1. To accommodate the finding that the superior colliculus is an important input to the brain stem pathways that generate saccades (the saccadic burst generator), a new model of the burst generator is proposed. Unlike the model of Robinson (61) from which it was derived, the model attempts to match a neural replica of change in eye position, which is the output of the burst generator, to a neural replica of change in target position, which is the output of the colliculus and the input to the model. 2. The elements of the model correspond to neurons known or thought to be associated with the actual primate saccadic burst generator and are mostly connected together in accord with the results of anatomical and physiological experiments. 3. The model was simulated on a digital computer to compare its behavior with that of the actual burst generator under normal and experimental conditions. Simulated peak burst frequency and saccade duration matched that obtained from monkey excitatory burst neurons and inhibitory burst neurons for saccades up to 15 degrees but did not match at larger sizes; stimulation of the omnipause neurons caused an interruption of the saccade, and the saccade resumed at the end of stimulation as in actual data; the model can generate the abnormally long-duration saccades seen under decreased alertness or various pathologies by changing the burst generator inputs and without having to change any properties of the neurons themselves or their connections; a simulated horizontal and vertical burst generator pair connected only through the omnipause neurons can generate realistic oblique saccades. 4. The implications of the model for higher-order control of the saccadic burst generator are discussed.

The Lobe Structure in Ice Accreted on an Aluminium Conductor in The Presence of a Dc Electric Field

1983 ◽  
Vol 4 ◽  
pp. 228-235 ◽  
Author(s):  
Luan C. Phan ◽  
Jean-Louis Laforte ◽  
Du D. Nguyen
Keyword(s):  
Electric Field ◽  
Local Heat Transfer ◽  
Local Heat ◽  
Air Bubbles ◽  
Experimental Conditions ◽  
Charged Droplets ◽  
Water Drops ◽  
The Difference ◽  
Negative Electric Field ◽  
Corona Wind

Supercooled droplets of 38 μm mean volume diameter are accreted on a smooth aluni mum cylinder of 3.15 cm in diameter in order to study the effect of an electrostatic field upon ice formation on a power-line conductor. The results obtained show that ice grown in the presence of an applied negative field of 15 kV cm−1 exhibits a cusped-lobe structure characterized by surfacial outward knobs, convex rings of fine air bubbles and radial lines of large air bubbles; in the same conditions, a positive electric field of 15 kV cm−1 does not produce such lobe features. On the other hand, accretion tests performed in the absence of an electric field with a 33 μm droplet spectrum show that the well-developed cusped-lobe structure appears in ice at low ambient temperature and air velocity. In the present experimental conditions, the formation of cusped lobes observed in the presence of a negative electric field could be explained by a decrease in the temperature of the deposit due to a reduction of impact velocity of the charged droplets and/or an increase in the local heat-transfer coefficient at the surface of the ice accretion. Corona wind from ice points, always in the opposite direction to the impinging droplets, may also reduce their impact velocities. In addition, corona wind and roughness of the surface may contribute to a better evacuation of the latent heat and thus decrease the deposit temperature. The difference between the effects of a negative DC field and those of a DC positive field of the same strength comes from a stronger ionization intensity and/or a stronger deformation of water drops in the negative electric field.

scholarly journals Active nitrogen of long duration, law of decay, and of increased brightness on compression

1935 ◽  
Vol 151 (874) ◽  
pp. 567-584 ◽  
Keyword(s):  
Small Area ◽  
Copper Surface ◽  
Metal Electrodes ◽  
Experimental Conditions ◽  
Active Nitrogen ◽  
Mercury Surface ◽  
Long Duration ◽  
Unfavourable Effect ◽  
The Subject ◽  
Low Pressures

1-Active Nitrogen-Influence of Vessel Walls on the Duration The length of time for which the afterglow associated with active nitrogen remains perceptible varies very greatly under different experimental conditions; and, what is more important, if we start from a given luminosity per cc of the gas, the integrated amount of light emitted before the luminosity sinks to zero varies also. This is connected with the fact that the walls of the certain gaseous impurities may have an unfavourable effect. In other words, the active nitrogen may go out of existence either by a luminous or a non-luminous reaction. If it is desired to study the homogeneous luminous reaction, then it becomes important to eliminate the other as far as possible. So far as I am aware, no systematic attempt has ever been made to do this, though many writers have referred to the subject. The electrodelss ring discharge at low pressures is suited for the production of active nitrogen, and it has the advantage that no metal electrodes need be introduced. An oxidized copper surface, even of very small area, immediately destroys the afterglow when introduced into it, and a clean (freshly formed) mercury surface is attacked with formation of nitride. In view of these facts it seemed best to avoid metal, though more information would be desirable.

An Investigation of the Electrical "Spike" Potentials Produced by the Sea Lamprey (Petromyzon marinus) in the Water Surrounding the Head Region

1956 ◽  
Vol 13 (3) ◽  
pp. 375-383 ◽  
Author(s):  
H. Kleerekoper ◽  
Kira Sibakin
Keyword(s):  
Electric Field ◽  
Fresh Water ◽  
Petromyzon Marinus ◽  
Longitudinal Axis ◽  
Sea Lamprey ◽  
Light Conditions ◽  
Head Region ◽  
Experimental Conditions ◽  
Gill Opening ◽  
Adult Lamprey

In the water surrounding the head of Petromyzon marinus electric triphasic spike potentials can be recorded which recur rhythmically at 0.4-second intervals and are synchronous with the externally visible movement of respiration. At a distance of 15 to 20 mm. from the animal, above the eye region, the potentials are from 200–300 μv in an adult lamprey, in fresh water. The electric field produced by these potentials extends several centimeters frontwards of the head depending on experimental conditions and factors now being studied. Posterior to the gill openings the potentials taper off sharply and no spikes could be recorded 50–70 mm. posterior to the last gill opening. The field is symmetrical around the longitudinal axis of the animal under the experimental conditions described. Strychnine and cocaine do not affect the characteristics of the spikes but curare decreases their potential considerably, depending on amounts injected and the condition of the experimental animal. Light conditions do not affect the production of the spikes. The possible function of the electric field for the sea lamprey is discussed.

Unusually long duration lightning electric field return strokes in Malaysia

2014 ◽  
Author(s):  
M. N. Hamzah ◽  
M. Z. A. Ab Kadir ◽  
C. Gomes ◽  
S. N. M. Arshad ◽  
N. Abdullah ◽  
...  
Keyword(s):  
Electric Field ◽  
Long Duration
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