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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    International journal of legal medicine 76 (1975), S. 321-333 
    ISSN: 1437-1596
    Keywords: Kehlkopfveränderungen, plötzlicher Tod ; plötzlicher Tod, Kehlkopfveränderungen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Description / Table of Contents: Zusammenfassung Mehrere in letzter Zeit beobachtete Fälle eines “plötzlichen Todes” durch Kehlkopfveränderungen gaben Anlaß zur eingehenden Erörterung dieser Problematik, zumal im Institut für Rechtsmedizin der Universität München unter 10 747 Obduktionen in den Jahren 1949 bis 1970 nur 6 Fälle gefunden wurden. Nach einer kurzen Beschreibung des anatomischen Aufbaues vom Kehlkopf werden entsprechend der in der allgemeinen Pathologie benutzten Gliederung die 4 Faktoren angeführt, die ätiologisch Ursache eines Kehlkopfverschlusses sein können: 1. Fehlbildungen 2. Kreislaufstörungen 3. Entzündungen 4. Geschwulstbildungen. Jeder der genannten Faktoren wird gesondert erörtert und die Fälle aus unserem Beobachtungsgut ihnen entsprechend zugeordnet. Neben der Frage nach der rechtsmedizinischen Bedeutung derartiger Todesfälle wird die Schwierigkeit der Beurteilung mancher pathomorphologischer und feingeweblicher Befunde diskutiert. Gleichzeitig wird auf die oft leere Anamnese hingewiesen, so daß lebensrettende Maßnahmen, wie zum Beispiel die Notfalltracheotomie und anderes, gar nicht oder sehr spät einsetzen können. Abschließend wird die Problematik der forensischen Begutachtung diskutiert, die sich bei der Abgrenzung der Larynxzysten hinsichtlich ihrer Ätiologie ergibt. Hier ist die Abklärung eines Kausalzusammenhanges zu eventuell vorangegangenen Intubationen von besonderer Bedeutung.
    Notes: Summary Several recently observed cases of “Sudden Death” caused by larynx lesions give reason for a special discussion of this problem. At the Institute of Legal Medicine only six cases were found in 10.747 autopsies between 1949 and 1970. A brief description of the anatomical structure of the larynx is followed by a discussion of the 4 general pathological entities, which might be the etiological cause of laryngeal obstruction: 1. Abnormalities 2. Disturbances of circulation 3. Inflammations 4. Tumors Besides the question of the forensic-medical importance of such fatal cases, the difficulty of evaluating some of the patho-morphologic and histologic findings is discussed. Simultaneously attention is drawn to the frequent lack of a clinical history, so that life-supporting measures such as tracheotomy and others are applied very late or not at all. Finally the problem of forensic evaluation of larynx-cysts and their etiology is presented. In this context the clarification of a causal relationship with possible previous intubations of the larynx is of major importance.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We have measured the temperature dependence of the effective quasiparticle recombination time in superconducting tin tunnel junctions by current and laser pulse excitation. The experimental times show satisfactory agreement with calculations based on the ray acoustic lifetime model of Eisenmenger et al. taking into account the film thickness dependence of the phonon reabsorption, 2Δ-phonon volume loss processes and phonon transmission from the junction into the substrate and liquid helium. On the basis of the BCS density of thermally excited quasiparticles and simplified rate equations for quasiparticle recombination, and from the analysis of measurements of decaying excess quasiparticle concentrations we obtain a mean valueN 0=(2.73±0.03) 1022 eV−1 cm−3 for the electronic density of states at the Fermi Surface in thin, evaporated tin films. This value differs less than 5% from that obtained from the experimental electronic heat-capacity coefficient of the bulk material.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1432-0630
    Keywords: 74
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The experimental recombination lifetime τeff of quasiparticles in superconducting films in general exceeds the intrinsic recombination lifetime τ R by phonon trapping. On the basis of geometric acoustic propagation and reabsorption of phonons emitted in quasiparticle recombination, τeff is calculated as a function of film thicknessd taking into account longitudinal and transverse phonon reabsorption, bulk loss processes and acoustical phonon transmission into the substrate. With increasing thicknessd three characteristic ranges are found: range 1 with film thicknessd small compared to the phonon reabsorption mean free path Λ w range 2 withd larger than Λ w and dominating boundary losses, and range 3, also withd larger than Λ w but with dominating bulk losses. For very smalld the relation between τeff and τ R , the intrinsic recombination lifetime, contains only the limiting angle of total reflection of phonons within the superconducting film. Therefore, τ R can be directly obtained by τ eff measurements and from the sound velocities of the film-substrate system. Range 2 is characterized by a linear dependence of τ eff ond. In this range it is not possible to obtain τ R from τ eff measurements, however, τ eff allows a determination of the phonon boundary transmission. Range 3 shows no thickness dependence of τ eff ond in the limit of larged values. In this range a further method for obtaining τ R from τ eff values is suggested.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-0630
    Keywords: 74
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Experimental quasiparticle recombination lifetime data for superconducting Al, Sn, and Pb films are compared with calculations based on a ray acoustic model taking account of the film thickness dependence of the reabsorption of recombination phonons. Information on the true or intrinsic quasiparticle recombination lifetime obtained from these and other data is discussed.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Temperature-dependent quasiparticle recombination lifetimesτ exp(T) and densitiesN 0 of electronic states at the Fermi level have been measured from time decay experiments of excess quasiparticle concentrations in evaporated, superconducting Al- and Pb-tunnel junctions. Current pulses were used to inject excess, nonthermal quasiparticles in a single junction acting simultaneously as generator and detector. The experimental lifetimes in “unperturbed” Al show satisfactory agreement with calculations based on the 2Δ-phonon trapping lifetime model.τ exp decreases with increasing perturbations of the Al film structure by oxygen background evaporation. In Pb the measured times indicate 2Δ-phonon volume losses. The densitiesN 0 in Pb-films and “unperturbed” as well as oxygen-perturbed Al-films differ by less than 5% from the corresponding bulk material data. Therefore, in trying to explain the enhancement of the transition temperature from 1.23 K to 1.85 K in perturbed, granular Al-films a change ofN 0 can be ruled out.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 28 (1977), S. 159-171 
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Observing the phonon yield, i.e. the ratio of the experimental phonon signal amplitude and the corresponding calculated value, phonon losses within the generation-detection system can be localized and determined quantitatively. With tin junctions on pure silicon substrates immersed in liquid helium the phonon yield is 3–5%. Under vacuum conditions the yield rises to 10–12% indicating strong phonon transmission to the helium bath. The experimental lifetime for 280 GHz phonons in the silicon substrate is longer than 65 µs indicating negligible volume losses and losses at the free substrate surface. It is further shown, that volume losses inside the phonon generator and detector are small compared to the total loss of about 90%. By phonon reverberation measurements we find evidence that the main sources for phonon losses are localized at the boundaries of the tunneling junctions to the substrate. This is supported by an increase of the phonon yield with improved polishing from about 9% (mechanical), 10% (chemical) to 12% (sputter etching). A SIMS analysis indicates the presence of carbonhydrates and probably of water in the boundaries. This layer of extraneous molecules together with the nonideal surface structure of the substrate and the evaporated films weakens the mechanical bonding between the tunnel junctions and the substrate and is possibly causing strong phonon splitting by anharmonic forces.
    Type of Medium: Electronic Resource
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