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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Astrophysics and space science 33 (1975), S. 127-140 
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A plane-wave analysis on a simplified scheme based on the Boussinesq approximation and shallow convection is used to establish the necessary conditions for stability of a differentiallyrotating, compressible flow between two coaxial cylinders subject to non-axisymmetric perturbations. To test the adequateness of this simplification, the sufficient conditions for stability are again established which agree with those obtained by a normal-mode analysis on an exact scheme in an earlier paper by the author. This model is applicable to stellar models with rotation Ω=Ω(ω), where ω is the radial distance from the axis of rotation (thez-axis). A necessary condition for stability, in the non-dissipative case, is found to be that $$\frac{1}{\varrho }G_\varpi S_\varpi + \frac{{k_z^2 }}{M}\Phi - \frac{1}{4}\frac{{m^2 }}{M}\left( {D\Omega } \right)^2 \geqslant 0$$ everywhere. Here,m andk z are the wave numbers in the ø- andz-direction, $$M \equiv k_z^2 + m^2 /\varpi ^2 ,D \equiv d/d\varpi ,G_\varpi \equiv - \varrho ^{ - 1} Dp,\varrho $$ the density,p the pressure,S ω and Φ the Schwarzschild and the Rayleigh discriminants defined as $$S_\varpi \equiv \left( {\gamma p/\varrho } \right)^{ - 2} Dp - D\varrho and \Phi \equiv ^{ - 3} d\left( {\varpi ^4 \Omega ^2 } \right)/d\varpi $$ respectively, γ the ratio of specific heats. This condition is also a sufficient one. Some conjectures regarding the stabilizing influence of uniform rotation and the destabilizing influence of differential rotation are also verified. The most striking instability mechanism introduced by shear forces and by radiative dissipation is the excitation of the stable motion of small oscillations into that of oscillations with growing amplitude, i. e., overstability. In the case of radiative dissipation and axisymmetric perturbations, the Goldreich-Schubert criterion is only necessary but not sufficient for stability. Instability sets in as soon as the Schwarzschild criterion is violated. When the perturbations are non-axisymmetric, instability always sets in as overstability as long as rotation is differential. This may explain the convective turbulence in the upper atmosphere where the radiation is active.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Astrophysics and space science 36 (1975), S. 407-426 
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract It is proposed that the observed double-component emission lines originate from the triangular Lagrangian points, L4 and L5, of the restricted three-body problem. The light curves of many close binary systems show absorption dips at ±60° of the primary (and sometimes also the secondary) minimum, indicating appreciable accumulation of matter at these points. The orbital velocity of L4 and L5 is derived as a function of period and the masses of the component stars. This equation is an independent relationship for determining the two stellar masses. It also reproduces Struve's empirical finding ofV 3∝P −1. The observed emission line velocity is consistently higher than the calculated orbital velocity of L4 and L5. This is due to the serious erosion of the low velocity sides of the emission components by the stellar and shell absorption lines. There are observational evidences which indicate the intermittent high velocity radial ejection of matter to be a mode of mass loss from the secondary. And the energy of mass motion from this ejection is sufficient, and may be responsible, for heating the gas at L4 and L5. The ionizing radiation emitted by the primary of the Algol systems is many orders of magnitude below that required by the observed strength of the emission lines. Some related discussion is also given to nova and dwarf nova systems.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 35 (1979), S. 261-268 
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A model Hamiltonian which includes one localized-type and one extended-type orbitals has been constructed for a more realistic description of magnetic impurities in nonmagnetic metals. We have used a variational method to study the ground state of this Hamiltonian. Due to the Hund's rule type coupling, under favorable condition the extended-and the localized-type orbitals can be both singly occupied to form a triplet state which contributes significantly to the local moment. We found a continuous change of local moments between the exact solutions at both the atomic and the band limits. A new mechanism has been discovered which may produce a ferromagnetic polarization cloud around the local moment. If so, this may provide an answer for the giant-moments formation.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    International journal of earth sciences 68 (1979), S. 696-706 
    ISSN: 1437-3262
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Description / Table of Contents: Abstract Mountain belts are constituted of thick prisms of tectonized sediments. The concept of geosyncline was originally created as an explanation of the tectonized sediments and how they were formed and deformed into the mountain ranges. In so far as the sediments are deformed into the mountain ranges, the original trough or trough-ridge complex (where the sediments occur) are geosynclines. Such an authentic concept of geosyncline has been seriously misunderstood. The present contribution attemps to discuss the two misinterpreted cases byDott (1974), i. e. island arc as evidence of orogenesis without thick sediments and thick continental-rise sediments are not destined to deform into the mountain range, as against the geosyncline theory. With clearance of this confusion, the authentic concept of geosyncline is further emphasized and designated as the orogenic concept of geosyncline. In the orogenic concept of geosyncline, the various named geosynclines are merely genetically related troughs developed in the history of mountain growth (Wang, 1972, 1975). They do not represent the different concepts of geosyncline that geologists conventionally believe; they are but various expressions of the corresponding different genetic status of a mountain-building “mother” geosyncline in labour of a mighty mountain range.
    Abstract: Résumé Les chaînes de montagnes proviennt de gros paquets de sédiments tectonisés. Le concept géosynclinal fut développé pour expliquer l'origine de ces sédiments tectonisés et leurs déformations. Les bassins ou les complexes de bassins et leurs rides pour autant que les sédiments aient été déformés en chaîne montagneuse, ont été qualifiés de gé osynclinaux. Cette définition authentique fut cependant mal comprise. L'article présent essaie d'expliquer les deux thèses deDott (1974) qui ont été mal comprises, relativement au concept de développement géosynclinal. Ici, les arces insulaires seront compris comme orogenèse sans paquets sédimentaires épais; de même les pentes continentales avec couche sédimentaire épaisse seront considérées comme n'étant pas destinées à un développement des chaînes de montagnes. Avec l'explication de cette confusion, le concept authentique de géosynclinal sera mis en valeur et il sera également considéré comme concept orogénique du géosynclinal. Les géosynclinaux qui sont désignés avec des noms différents dans ce concept, sont des bassins génétiquement apparentés qui se sont développés pendant la formation des montagnes. (Wang 1972, 1975). Ils ne peuvent pas représenter les concept acceptés, Mais ils seront considérés comme représentant des expressions différentes d'une “mère-géosynclinale” génératriee d'une chaîne de montagnes puissante.
    Notes: Zusammenfassung Gebirgsketten bestehen aus mächtigen Paketen von tektonisierten Sedimenten. Das Konzept der Geosynklinalen wurde entwickelt, um die Entstehung dieser tektonisierten Sedimente und ihrer Deformationen zu erklären. Danach wurden Becken oder Komplexe von Becken und ihre Flanken, deren Sedimente in Gebirgsketten deformiert wurden, als Geosynklinalen bezeichnet. Diese ursprüngliche Definition wurde jedoch mißverstanden. Der vorliegende Beitrag versucht die beiden mißverstandenen Thesen vonDott (1974) in Bezug auf das Originalkonzept der Geosynklinalen zu diskutieren. In diesen Thesen wurden einerseits Inselbögen als Nachweis für eine Orogenese ohne Sedimentpakete, andererseits mächtige Sedimente von Kontinentalschwellen als ungeeignet für die Bildung von Gebirgsketten betrachtet. Beide Fälle stehen nicht im Widerspruch mit dem ursprünglichen Konzept der Geosynklinale; und es zeigt sich weiterhin, daß das Orogenkonzept der Geosynklinalbildung unverändert bestehen bleiben kann. Die in diesem Konzept mit verschiedenen Namen bezeichneten Geosynklinalen sind miteinander genetisch verwandte Becken, die sich während der Gebirgsbildung entwickelt haben, (Wang, 1972, 1975). Sie repräsentieren nicht wie in herkömmlichen Konzepten der Geosynklinale eigenständige Entwicklungen, sondern werden als Repräsentanten verschiedener Zustände einer „Mutter-Geosynklinale“ angesehen, die mit der Entstehung einer orogenen Gebirgskette verbunden sind.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    The annals of regional science 12 (1978), S. 39-51 
    ISSN: 1432-0592
    Source: Springer Online Journal Archives 1860-2000
    Topics: Architecture, Civil Engineering, Surveying , Geography , Economics
    Notes: Abstract It is well-known that theories of urban land use and location, set forth by von Thünen and his followers, explained quite successfully the agricultural and residential locations. Unfortunately, there has been virtually no comparative static analysis performed to probe their underlying properties. The present paper attempts accordingly to take further steps in the direction of generalizing the theory of intra-urban location and land use and to present a general comparative static analysis. It will be shown that, in general, the intra-urban optimum location is a function of the wage rate, the transport rate on the final product, the elasticity of demand, the population of the city and the income (or wealth) of the city. In the process, it is demonstrated that characteristics of production function are crucial in conducting our comparative static analysis.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Archiv der Mathematik 27 (1976), S. 249-252 
    ISSN: 1420-8938
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Archiv der Mathematik 32 (1979), S. 295-304 
    ISSN: 1420-8938
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 35 (1979), S. 1519-1520 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Peripheral blood samples from 52 women, including 16 with herpes genitalis and 36 healthy persons, were studied to enumerate subpopulations of lymphocytes. It was found that the mean percentage of ‘active’ T lymphocytes was significantly less in the patients with herpes genitalis than in the controls.
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  • 9
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Localization of polysaccharides in the freeze-substituted, Eponembedded ovaries of Paspalum longifolium prior to pollination was carried out by periodic acid-Schiff's (PAS), periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-AgPr) and periodic acid-thiosemicarbazide-osmium (PA-TSC-OsO4) reactions. The specificities of these three reactions were also studied. These three reactions are all effective for light microscopic demonstration of polysaccharides in the filiform apparatus, starch grains in the cells and PAS substance in the micropylar region. Nonspecific staining of the nucleoli of the egg and polar nuclei was observed in the PAS reaction. The PA-TSC-AgPr reaction is very specific for polysaccharides but its overall reaction takes a much longer period of time than the PAS reaction. The PA-TSC-OsO4 reaction colors the cytoplasm and nuclei of most cells and therefore stains of the cell walls, especially those of the egg cell and synergids, do not stand out clearly. The synergid cytoplasm contains some amorphous polysaccharides and thus it colors even in PAS and PA-TSC-AgPr preparations. In the mature embryo sac, the egg and central cell as well as antipodals are vacuolated but the two synergids have no visible vacuoles under light microscope. Each synergid has a prominent filiform apparatus at the micropylar end, which stains intensely in all three preparations. The walls of the central cell and antipodals adjacent to the nucellar cells have many inward papillae which are also intensely stained in all three preparations. Starch grains are abundant in the ovary wall and usually absent in the nucellus and integuments. They are present in the egg, central cell and antipodals, but not in the two synergids.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Mathematische Annalen 215 (1975), S. 47-58 
    ISSN: 1432-1807
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
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