scholarly journals On the secondary spectrum of hydrogen

1920 ◽  
Vol 96 (679) ◽  
pp. 382-388 ◽  
Keyword(s):  
Hydrogen Atom ◽  
Relative Intensity ◽  
Fundamental Difference ◽  
The Other ◽  
Pure Hydrogen ◽  
Balmer Series ◽  
Reduced Pressure ◽  
Theoretical Investigations ◽  
Abundant Evidence ◽  
Great Complexity

Theoretical investigations of the origin of spectra in relation to the structure of the atom have concentrated especially on the spectrum of hydrogen, on account of the supposed simplicity of the hydrogen atom. They have, however, been confined almost exclusively to the Balmer series, and have ignored the difficulties which arise from the fact that hydrogen possesses another spectrum, usually known as the secondary spectrum, which is of great complexity, and the co-ordination of whose lines into recognised bands or series of lines is still in a very unfinished state. The investigations of Buisson and Fabry, in which the physical widths of spectrum lines were measured with the interferometer, refer at least a part of the lines of the secondary spectrum to the hydrogen atom, and the complications introduced into theoretical investigations cannot therefore be impartially waived by the assumption that the molecule is concerned in the production of the secondary spectrum. As regards the relation of the two spectra, there is abundant evidence of a fundamental difference in their origin. In many celestial spectra the lines of the Balmer series constitute one of the most prominent features, whilst the identification of lines of the secondary spectrum is at least extremely doubtful. In the laboratory it has long been known that the relative intensity of the secondary spectrum is greatly reduced by the presence of impurities, notably oxygen, in vacuum tubes containing hydrogen, and by the passage of powerful condensed discharges. On the other hand, under conditions in which an uncondensed discharge from an induction coil is passed through very dry and pure hydrogen at a reduced pressure, the lines of the secondary spectrum may rival those of the Balmer series in intensity.

Article

1998 ◽  
Vol 76 (2) ◽  
pp. 153-162
Author(s):  
P Kurunczi ◽  
K Becker ◽  
K Martus
Keyword(s):  
Hydrogen Atom ◽  
Organic Compounds ◽  
Cross Sections ◽  
Impact Energy ◽  
Atomic Hydrogen ◽  
Vacuum Ultraviolet ◽  
The Other ◽  
Dissociative Excitation ◽  
Balmer Series ◽  
Break Up

The vacuum ultraviolet (VUV) emissions of the hydrogen Lyman series following the dissociative excitation of the Si-organic compounds tetraethoxysilane (TEOS), tetramethylsilane (TMS), and hexamethyldisiloxane (HMDSO) by controlled electron impact were analyzed. Absolute photoemission cross sections from threshold to 200 eV and appearance potentials were determined for the Lyman-α and Lyman-β emissions for each of the three targets. The measured apparent emission cross sections at 100 eV impact energy for the Lyman-α lines are 6.0 x 10-19 cm2 for TMS, 6.5 x 10-19 cm2 for HMDSO and 1.1 x 10-18 cm2 for TEOS. The apparent Lyman-α cross sections for all three targets contained significant cascade contributions from the H Balmer series. Detailed studies of the near threshold regions indicated that several break-up mechanisms of the parent molecules contribute to the emissions. The lowest onsets for HMDSO, and TEOS were attributed to the removal of a single excited atomic hydrogen atom in the n=2 state. Additional onsets at higher energies could not be uniquely correlated in all cases with a particular break-up channel and (or) cascading, since the other fragments in these processes were not identified. The Lyman-β apparent emission cross sections were also measured and we found values of 1.3 x 10-19 cm2 for TMS, 1.6 x 10-19 cm2 for HMDSO, and 2.0 x 10-19 cm2 for TEOS at an impact energy of 100 eV. PACS Nos. 52.20Fs and 34.80Gs

‘Synergy’, ‘energy’ and ‘symbol’ in Pavel Florensky and Palamism

2021 ◽  
Vol 74 (2) ◽  
pp. 147-157
Author(s):  
Dmitry Biryukov
Keyword(s):  
Fundamental Difference ◽  
The Other ◽  
Pavel Florensky

AbstractThis article is a study of Pavel Florensky's philosophy of symbol in the context of his discovery of Palamism in the 1910s, when Florensky started to speak of symbol using Palamite language. It proposes a fundamental difference between Florensky's and Palamas’ teachings on symbol: Palamas views a natural symbol as the energy of an essence, while for Florensky symbol is the essence itself, the energy of which synergises with the energies of other essence. In this context the prehistory of the concept of synergy in Florensky is studied, leading to the identification of a further difference in the ontologies of Florensky and Palamas: while Florensky's ‘essence-energy’ has the property of necessary correlation with the ‘other’, following the tendencies of the philosophy of that epoch, in Palamas ‘energy’ does not presuppose any necessary correlation with the ‘other’. The author connects this difference in ontologies between the two thinkers with their respective teachings on symbol.

Rolling and Recrystallization Textures in High Purity Al Cold Rolled to Very High Rolling Reductions

2005 ◽  
Vol 495-497 ◽  
pp. 603-608 ◽  
Author(s):  
Atsushi Todayama ◽  
Hirosuke Inagaki
Keyword(s):  
Cold Rolling ◽  
High Purity ◽  
Work Hardening ◽  
Dynamic Recovery ◽  
The Other ◽  
Rolling Reduction ◽  
Theoretical Investigations ◽  
Theoretical Predictions ◽  
Cold Rolled ◽  
Very High

On the basis of Taylor-Bishop-Hill’s theory, many previous theoretical investigations have predicted that, at high rolling reductions, most of orientations should rotate along theβfiber from {110}<112> to {123}<634> and finally into the {112}<111> stable end orientations. Although some exceptions exist, experimental observations have shown, on the other hand, that the maximum on the β fiber is located still at about {123}<634> even after 97 % cold rolling. In the present paper, high purity Al containing 50 ppm Cu was cold rolled up to 99.4 % reduction in thickness and examined whether {112}<111> stable end orientation could be achieved experimentally. It was found that, with increasing rolling reduction above 98 %, {110}<112> decreased, while orientations in the range between {123}<634> and {112}<111> increased, suggesting that crystal rotation along the βfiber from {110}<112> toward {123}<634> and {112}<111> in fact took place. At higher rolling reductions, however, further rotation of this peak toward {112}<111> was extremely sluggish, and even at the highest rolling reduction, it could not arrive at {112}<111>. Such discrepancies between theoretical predictions and experimental observations should be ascribed to the development of dislocation substructures, which were formed by concurrent work hardening and dynamic recovery. Since such development of dislocation substructures are not taken into account in Taylor-Bishop-Hill’s theory, it seems that they can not correctly predict the development of rolling textures at very high rolling reductions, i. e. stable end orientations. On annealing specimens rolled above 98 % reduction in thickness, cube textures were very weak, suggesting that cube bands were almost completely rotated into other orientations during cold rolling. {325}<496>, which lay at an intermediate position between {123}<634> and {112}<111> along theβfiber, developed strongly in the recrystallization textures.

scholarly journals Note on the intensity decrement in the balmer series

1919 ◽  
Vol 96 (675) ◽  
pp. 112-119 ◽  
Keyword(s):  
Hydrogen Atom ◽  
Low Pressure ◽  
Quantitative Comparison ◽  
The Sun ◽  
Previous Knowledge ◽  
Balmer Series ◽  
Celestial Bodies ◽  
Theoretical Considerations

One of the most remarkable examples of spectrum lines which are common in celestial bodies, but which have hitherto resisted all attempts to reproduce them in the laboratory, is afforded by the higher members of the Balmer series of hydrogen. As many as 29 members of this series have been observed by Dyson and Evershed in the chromosphere of the sun, but the greatest number observed in the laboratory by Ames and by Cornu was only 13, and the last of these were of such a character that it would hardly have been possible to record them without a previous knowledge of their localisation. In many respects the failure to reproduce in the laboratory lines whose chemical origin is known, and which are so prominent in celestial spectra, is even more conspicuous than in the case of the nebular and coronal lines, which cannot yet be referred to any atom known in chemistry, and which may be due to substances which do not, or perhaps cannot, exist under terrestrial conditions. A further interest has been added to the problem by the important theoretical wrork of Bohr, whose theory of the production of the Balmer series requires that the space occupied by a hydrogen atom, in the process of emitting lines of the higher members of the Balmer series, is such that these radiations cannot be expected to be visible except under conditions of extremely low pressure. Bohr has pointed out that this view is consistent with the appearance of the lines in celestial spectra, and our inability to produce them under the conditions ordinarily obtaining in the laboratory. Liveing and Dewar have found that in a mixture of the more volatile gases of the atmosphere, consisting mainly of neon and helium and containing hydrogen, the Balmer series could be traced as far as the ninth member; and in a recent investigation we have made a quantitative comparison of the distribution of intensity in the earlier members of the series in hydrogen, and in neon containing hydrogen as an impurity. This observation of Liveing and Dewar is remarkable, but we have recently found that similar results can be obtained in helium containing hydrogen at pressures so great that, on the theoretical considerations above referred to, it would seem impossible that these radiations should be detected.

The Body in Theory

1998 ◽  
Vol 16 (4) ◽  
pp. 387-400 ◽  
Author(s):  
Felicity J Callard
Keyword(s):  
Queer Theory ◽  
20Th Century ◽  
The Body ◽  
The Other ◽  
Industrial Capitalism ◽  
Late 20Th Century ◽  
The Social ◽  
Theoretical Investigations ◽  
The One ◽  
Do So

Geographers are now taking the problematic of corporeality seriously. ‘The body’ is becoming a preoccupation in the geographical literature, and is a central figure around which to base political demands, social analyses, and theoretical investigations. In this paper I describe some of the trajectories through which the body has been installed in academia and claim that this installation has necessitated the uptake of certain theoretical legacies and the disavowal or forgetting of others. In particular, I trace two related developments. First, I point to the sometimes haphazard agglomeration of disparate theoretical interventions that lie under the name of postmodernism and observe how this has led to the foregrounding of bodily tropes of fragmentation, fluidity, and ‘the cyborg‘. Second, I examine the treatment of the body as a conduit which enables political agency to be thought of in terms of transgression and resistance. I stage my argument by looking at how on the one hand Marxist and on the other queer theory have commonly conceived of the body, and propose that the legacies of materialist modes of analysis have much to offer current work focusing on how bodies are shaped by their encapsulation within the sphere of the social. I conclude by examining the presentation of corporeality that appears in the first volume of Marx's Capital. I do so to suggest that geographers working on questions of subjectivity could profit from thinking further about the relation between so-called ‘new’ and ‘fluid’ configurations of bodies, technologies, and subjectivities in the late 20th-century world, and the corporeal configurations of industrial capitalism lying behind and before them.

scholarly journals THE ENERGY EIGENVALUES OF THE TWO DIMENSIONAL HYDROGEN ATOM IN A MAGNETIC FIELD

2006 ◽  
Vol 15 (06) ◽  
pp. 1263-1271 ◽  
Author(s):  
A. SOYLU ◽  
O. BAYRAK ◽  
I. BOZTOSUN
Keyword(s):  
Magnetic Field ◽  
Hydrogen Atom ◽  
Iteration Method ◽  
Weak Magnetic Field ◽  
The Other ◽  
Asymptotic Iteration Method ◽  
Iterative Approach ◽  
Two Dimensional ◽  
Energy Eigenvalues ◽  
The Magnetic Field

In this paper, the energy eigenvalues of the two dimensional hydrogen atom are presented for the arbitrary Larmor frequencies by using the asymptotic iteration method. We first show the energy eigenvalues for the case with no magnetic field analytically, and then we obtain the energy eigenvalues for the strong and weak magnetic field cases within an iterative approach for n=2-10 and m=0-1 states for several different arbitrary Larmor frequencies. The effect of the magnetic field on the energy eigenvalues is determined precisely. The results are in excellent agreement with the findings of the other methods and our method works for the cases where the others fail.

Husserl and Levinas

2018 ◽  
Vol 26 (51) ◽  
pp. 115-126
Author(s):  
João Carvalho ◽  
Keyword(s):  
Transcendental Phenomenology ◽  
Fundamental Difference ◽  
The Other ◽  
Close Reading ◽  
Key Concepts ◽  
Alter Ego

This paper presents two different, although related, approaches to the problem of the experience of the other person: E. Husserl’s phenomenology of intersubjectivity and E. Levinas’ ethics. I begin by (1) addressing the transcendental significance of the experience of intersubjectivity in the broader context of Husserl’s transcendental phenomenology. I then turn to (2) Husserl’s solution to the paradox of constituting the alter ego, identifying and elucidating the key‑concepts of his inquiry. I hold that throughout his analysis there is a dominant underlying meaning in which the alterity of the other person is progressively suppressed and, ultimately, elided. Finally, I discuss (3) the consequences of Husserl’s analysis of the other in light of Levinas’ ethics. I hold that Husserl’s claim that there is a fundamental difference between the experience of myself and my analogical experience of the other is the basis upon which Levinas’ develops a new concept of experience, not as perception but as encounter. Upon close reading, I claim that Levinas’ revision of the topic of alterity is, ultimately, a consequence of Husserl’s transcendental analysis of intersubjectivity.

scholarly journals Structure of the Balmer jump

2018 ◽  
Vol 613 ◽  
pp. A55
Author(s):  
F. Calvo ◽  
L. Belluzzi ◽  
O. Steiner
Keyword(s):  
Hydrogen Atom ◽  
Absorption Coefficient ◽  
Total Cross Section ◽  
Analytical Model ◽  
Cross Section ◽  
Quantum Structure ◽  
Balmer Series ◽  
Polarization Phenomena ◽  
Definition Of ◽  
Rapid Drop

Context.The spectrum of the hydrogen atom was explained by Bohr more than one century ago. We revisit here some of the aspects of the underlying quantum structure, with a modern formalism, focusing on the limit of the Balmer series.Aims.We investigate the behaviour of the absorption coefficient of the isolated hydrogen atom in the neighbourhood of the Balmer limit.Methods.We analytically computed the total cross-section arising from bound-bound and bound-free transitions in the isolated hydrogen atom at the Balmer limit, and established a simplified semi-analytical model for the surroundings of that limit. We worked within the framework of the formalism of Landi Degl’Innocenti & Landolfi (2004, Astrophys. Space Sci. Lib., 307), which permits an almost straight-forward generalization of our results to other atoms and molecules, and which is perfectly suitable for including polarization phenomena in the problem.Results.We analytically show that there is no discontinuity at the Balmer limit, even though the concept of a “Balmer jump” is still meaningful. Furthermore, we give a possible definition of the location of the Balmer jump, and we check that this location is dependent on the broadening mechanisms. At the Balmer limit, we compute the cross-section in a fully analytical way.Conclusions.The Balmer jump is produced by a rapid drop of the total Balmer cross-section, yet this variation is smooth and continuous when both bound-bound and bound-free processes are taken into account, and its shape and location is dependent on the broadening mechanisms.

Observations on the Biting-habits of African Mosquitos in the Genus Eretmapodites Theobald

1956 ◽  
Vol 46 (4) ◽  
pp. 761-772 ◽  
Author(s):  
A. J. Haddow
Keyword(s):  
Environmental Influence ◽  
Activity Patterns ◽  
Fundamental Difference ◽  
The Other ◽  
Activity Curve ◽  
The Moment ◽  
The One

The biting-habits of mosquitos in the genus Eretmapodites Theobald, as shown by 24-hour catches, display a certain uniformity in that all the species studied are essentially diurnal and bite very close to the ground, in shade. They do not enter dwellings.When, however, two localities are compared (the Entebbe area and Bwamba County) it is found that there is a fundamental difference in behaviour. At Entebbe there is an exceedingly well-marked wave of activity before sunset. This does not occur in Bwamba, where the cycle shows no pronounced characteristics apart from its generally diurnal nature. It is shown that this difference arises from the fact that in Bwamba the first hour of biting-activity tends to be the most intense (no matter when it occurs) whereas in Entebbe the hour before sunset is almost always preferred.One group (the E. chrysogaster group) is present in both localities. In Entebbe it shows an activity curve of the one type, and in Bwamba a curve of the other type.It is concluded that some environmental influence must be involved. At the moment, however, no suggestion can be made concerning the nature of this influence, beyond the fact that the activity-patterns concerned are not easily explained in terms of microclimate.

Rapports intertextuels et (re)constructions identitaires dans le roman Bois rouge de Jean-Marie Touratier

2021 ◽  
pp. 17-30
Author(s):  
Loredana Stănică ◽  
Keyword(s):  
The Other ◽  
16Th Century ◽  
The Novel ◽  
Military Leader ◽  
Jean De Lery ◽  
History Of ◽  
The Military ◽  
The Antarctic ◽  
The Relationship ◽  
Great Complexity

Published in 1993, the novel Bois rouge by Jean-Marie Touratier brings to life the history of the short-lived French colony of Brazil, the Antarctic France, whose existence, reduced to only five years (1555-1560), was described in the travelogues written in the 16th century by André Thevet (Les Singularitez de la France Antarctique - The New Found World, or Antarctike) and Jean de Léry (Histoire d’un voyage faict en la terre du Brésil – History of a Voyage to the Land of Brazil). Beneath the appearance of a simple story told by an ironic voice, sometimes even satirical towards the military leader of the French colony, the Knight of Malta Nicolas Durand de Villegagnon and his chaplain, André Thevet, future cosmographer of the kings of France, the novel delves into issues of great complexity, such as (the issue of) identity and the relationship to the Other (the American “savage”).

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