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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 36 (1995), S. 4792-4814 
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: The stability analysis for spherically symmetric stellar equilibrium models with respect to "small'' adiabatic Lagrangian perturbations leads to the consideration of a class of densely defined, linear symmetric operators in Hilbert space, which are induced by certain singular vector–integro–partial differential operator. The extension properties of these operators as well as the spectral properties of the linear self-adjoint extensions which are chosen by physical boundary conditions are investigated. For this, the equilibrium models are assumed to be polytropic, with a constant adiabatic index only near the center and near the boundary of the star. Among others it is shown that the operators of the class having a polytropic index near the boundary which is ≥1 are in particular essentially self-adjoint and have a closure with a pure point spectrum. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 36 (1995), S. 4815-4825 
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: The stability analysis with respect to "small'' radial adiabatic perturbations of spherically symmetric stellar equilibrium models which are polytropic with a constant adiabatic index only near the center and the boundary of the star leads to the consideration of a class of singular minimal Sturm–Liouville operators. It is shown that the physical boundary conditions choose in a unique way the corresponding Friedrichs extensions. Moreover, all linear self-adjoint extensions of the members of the class are determined and are shown to have a purely discrete spectrum. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Communications in mathematical physics 204 (1999), S. 397-423 
    ISSN: 1432-0916
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Physics
    Notes: Abstract: The completeness of the quasinormal modes of the wave equation with Pöschl–Teller potential is investigated. A main result is that after a large enough time t 0, the solutions of this equation corresponding to &C ∞-data with compact support can be expanded uniformly in time with respect to the quasinormal modes, thereby leading to absolutely convergent series. Explicit estimates for t 0 depending on both the support of the data and the point of observation are given. For the particular case of an “early” time and zero distance between the support of the data and observational point, it is shown that the corresponding series is not absolutely convergent, and hence that there is no associated sum which is independent of the order of summation.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Foundations of physics 20 (1990), S. 459-469 
    ISSN: 1572-9516
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Maxwell's equations are established for the free electromagnetic field in two-dimensional space-times. In Minkowski space they are solved under the boundary conditions set by a pair of uniformly accelerated “plates.” With the help of these solutions we determine the regularized energy-momentum tensor of the canonically quantized electromagnetic field at the position of one of the “plates.” Thereby (as a new result) we arrive at a Casimir effect in an accelerated reference frame.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 92 (1959), S. 1957-1963 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei der Umsetzung von CCl4 mit Si/Cu-Gemischen entstehen in geringer Menge weiterhin3) die Verbindungen (Cl3Si)2C:C:C(SiCl3)2 (IV) und Cl2C:C(Cl)·SiCl3 (III), deren Konstitutionen bewiesen werden.  -  Die Bildung von IV wird durch Umsetzung von (Cl3Si)2CCl2 mit Kupfer erklärt. Sie führt bei niedriger Temperatur teilweise auch zum (Cl3Si)2C:C(SiCl3)2 (IX). III, das bei der Einwirkung von Cl3SiCCl3 auf Si/Cu-Gemische auch auftritt, entsteht durch β-Spaltung aus Cl3Si·(Cl)2C·C(Cl)2·SiCl3.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 92 (1959), S. 1018-1027 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei nochmaliger Untersuchung der Umsetzung von CCl4 mit Si/Cu-Gemischen werden, wie bereits bekannt, SiCl4, C2Cl4 und Si2Cl6 gefunden. Darüber hinaus lief eine direkte Synthese. Sie führte wahrscheinlich zur Bildung des allerdings dabei nicht nachgewiesenen Cl3C·SiCl3. Dagegen wurde die nach der direkten Synthese entstandene Verbindung C(SiCl3)4 erstmalig aufgefunden.  -  Die Entstehung der ebenfalls nachgewiesenen Verbindungen Cl3SiC·C⋮CC·SiCl3 und Cl3SiC·(Cl)C:C(Cl)C·SiCl3 wird durch Dechlorierungen des Cl3CC·SiCl3 mit Kupfer erklärt.  -  Für die neuen Verbindungen wurden Strukturbeweise geführt. Es wurden C2Cl4 und Cl3CC·SiCl3 mit Si/Cu-Gemischen umgesetzt. Die letzte Umsetzung ergab dieselben Reaktionsprodukte wie das CCl4, so daß auch bei diesem eine direkte Synthese über das Cl3CC·SiCl3 glaubhaft gemacht ist.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 311 (1961), S. 180-185 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The RAMAN spectrum of Cl3Si—C≡C—SiCl3 and the RAMAN and infrared spectra of (CH3)3Si—C≡C—Si(CH3)3 and (CH3O)3Si—C≡C—Si(OCH3)3 are reported and the frequencies assigned as for as possible. The spectra are in agreement with free rotation about the Si—C bonds (point group D3h). The C≡C bond is reinforced with increasing electronegativities of the trisilyl groups.
    Notes: Das RAMAN-Spektrum von Cl3Si—C≡C—SiCl3 und die RAMAN- und IR-Spektren von (CH3)3Si—C≡C—Si(CH3)3 und (CH3O)3Si—C≡C—Si(OCH3)3 werden mitgeteilt und die Schwingungsfrequenzen soweit wie möglich zugeordnet. Die Spektren stehen im Einklang mit freier Drehbarkeit um die Si—C-Bindung (Punktgruppe D3 h). Die Stärke der C—C-Bindung wächst mit steigender Gruppenelektronegativität der Trisilylgruppen.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 95 (1962), S. 3030-3033 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: G. Fritz und J. Grobe beschreiben eine linear gebaute Verbindung (C6H16Si2) mit einer Si- C-Doppelbindung, (CH3)2Si; CH. Si(CH3)3, die sie aus Pyrolyseprodukten des Si(CH3(4 gewonnen haben. Es wurde eine Verbindung mit der gleichen Zusammensetzung und den gleichen physikalischen und chemischen Eigenschaften erhalten, der auf Grund ihrer Darstellung aus Brommethyl- dimethyl-chlorsilan und Magnesium jedoch Vierring-Struktur (VI) ohne Doppelbindung zukommen muß.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 31 (1966), S. 1-6 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Brennender H2, ferner HSiCl3, Si2Cl6 und CH3HSiCl2 können im Gegensatz zu Kohlenwasserstoffen und HSi-Gruppen-freien Methylchlorsilanen mit BrF2CCF2Br oder CF3J nicht gelöscht werden. H2SiCl2 ist schon ohne, CH3HSiCl2 erst in Gegenwart von KMnO4 usw. schlagentzündlich. Die Reibungsentzündlichkeit der Silicomesoxalsäure beruht auf einer Oxydation. Die Verbrennungsvorgänge müssen sich also je nach Substanz erheblich unterscheiden.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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