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  • 1
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Astronomy and Astrophysics 5 (1967), S. 351-398 
    ISSN: 0066-4146
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Physik
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    ISSN: 1749-6632
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Allgemeine Naturwissenschaft
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    ISSN: 1749-6632
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Allgemeine Naturwissenschaft
    Notizen: The Energetic Gamma-Ray Experiment Telescope (EGRET) has observed gamma-rays bursts with the highest energy gamma-rays and the longest high energy emission to date. EGRET measures the high energy gamma-rays with its large NaI scintillator (1 to 200 MeV) and its spark chamber (30 MeV to 30 GeV). The spark chamber also measures time and arrival directions of individual photons allowing locations for the energetic bursts to be determined. Since the Compton Gamma Ray Observatory launch in 1991, EGRET has observed five bursts in the spark chamber with several having gamma-ray energies grater than 1 GeV. The recording breaking burst, GRB940217, had gamma-rays up to 18 GeV and lasted over 5000 seconds. The results for the energetic bursts are presented. The high energies observed from these gamma-ray bursts set constraints for the burst distances.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 251 (1974), S. 397-399 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Here we report observations of the Crab above 35 MeV made with the high energy gamma-ray telescope flown on SAS-2. The detector and technique have been described11,12. Fig. 1 Distribution of g-ray arrival time in fractions of a pulse period for g rays above 35 MeV from the direction of NP0532. M ...
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 255 (1975), S. 208-210 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Details of the instrument are given by Derdeyn et al.\ The A-dome constructed out of 1.5cm thick scintillator has an average collection area of about 2.5X103 cm2 and is an almost omnidirectional detector only being insensitive to directions within a small cone (30 half angle) centred around the ...
    Materialart: Digitale Medien
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  • 6
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] The y-ray source Geminga (2CG195 + 04) was first seen by the SAS-2 satellite (refs 2-4) in observations made roughly 20 years ago. Then, as now, it was one of the three strongest high-energy y-ray sources in the sky, the other two being the Crab and Vela pulsars PSR0531 + 21 and ...
    Materialart: Digitale Medien
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  • 7
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Following the SAS-2 and COS-B high-energy y-ray observations of the Crab (0531 + 21) and Vela (0833-45) pulsars1'2, searches were made for additional y-ray pulsars3'5. No other positive results were then found, but calculations have indicated that y-ray emission is likely from other ...
    Materialart: Digitale Medien
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  • 8
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] This event occurred on 1994 February 17 at 82,962s UT. Figure 1 shows the location of the burst as determined by the Compton Telescope (COMPTEL)8, the Energetic Gamma-Ray Experiment Telescope (EGRET) and Interplanetary Network (Ulysses/Burst And Transient Source Experiment, BATSE). Figure 2 shows ...
    Materialart: Digitale Medien
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Lung 134 (1967), S. 228-238 
    ISSN: 1432-1750
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Comparable data for patients suffering from chronic progressive tuberculosis that can be used as points of reference, for example in examining the effect of chemotherapy, are difficult to obtain and often incorrect. Dates of death however are unequivocal. Therefore, the age of miners who died of silico-tuberculosis in Germany was closely examined. We compared the age of death of silico-tuberculosis patients with the age of death of silicosis patients. From 1954 through 1964, 5310 miners died of the sequelae of silico-tuberculosis, 15695 of the sequelae of silicosis. Prior to this time, the yearly death rate was probably higher. Both groups are, as we have illustrated, homogeneous. The average age of death of patients with silico-tuberculosis was 13,6 years higher in 1964 than it was during the period of time of 1937 through 1940, and 9,6 years higher than in 1948. The average age of death of patients with silicosis did rise in about the same manner. The life expectancy of the silicosis and silico-tuberculosis miners approached the life expectancy of the general population steadily. The mortality of silico-tuberculosis patients decreased, probably due to a less frequent occurrence of tuberculosis in connection with silicosis. For the average age of death, a regression analysis was performed for both groups for the period of time from 1948 through 1964. These equations were extrapolated to 1970. This made a further rising trend obvious which will most likely level off in 1970. The calculated (max.) age of death for patients suffering from silico-tuberculosis will then be 66,0 years, and of patients suffering from silicosis 67,5 years. The cause for this rise is discussed. In addition the change of the mean age of death was established and an explanation was given why several points exceeded the standard deviations. Through the regression analysis and the determination of the change of the average age of death, points of reference were established that may be useful in examining the success of the present as well as of a future modified chemotherapy.
    Notizen: Zusammenfassung Bei chronisch progressiven Tuberkulosen sind vergleichbare Krankheitsdaten, die als Bezugspunkte beispielsweise bei der Untersuchung der chemotherapeutischen Effektivität dienen könnten, schwierig zu gewinnen und meistens mit einer großen Fehlerbreite behaftet. Demgegenüber sind die Sterbedaten eindeutig. Deswegen wurde das durchschnittliche Sterbealter der in der Bundesrepublik Deutschland an den Folgen einer Siliko-Tuberkulose verstorbenen Bergleute untersucht. Die an den Folgen einer Silikose Verstorbenen wurden als Vergleichskollektiv gegenübergestellt. 1954 bis 1964 starben 5310 Bergleute an den Folgen einer Siliko-Tuberkulose, 15695 an den Folgen einer Silikose. Vordem waren die jährlichen Todesfälle wahrscheinlich zahlreicher. Die beiden Kollektive sind aus näher erläuterten Gründen vergleichsweise homogen. Das durchschnittliche Sterbealter bei Siliko-Tuberkulose lag 1964 13,6 Jahre höher als in der Zeit von 1937 bis 1940, 9,6 Jahre höher als 1948. Ziemlich parallellaufend stieg auch das durchschnittliche Sterbealter bei Silikose an. Der Abstand zu dem durchschnittlichen Sterbealter der übrigen Bevölkerung wurde stetig kleiner. Außerdem sank die Siliko-Tuberkulose-Mortalität, wahrscheinlich infolge der abnehmenden Tuberkuloserate bei Silikose. Für das durchschnittliche Sterbealter wurden getrennt für beide Kollektive für die Jahre 1948 bis 1964 Regressionsanalysen durchgeführt und die Gleichungen über ihren Gültigkeitsbereich hinaus bis 1970 extrapoliert. Dadurch ließ sich eine Entwicklung bestimmen mit einem durch Extrapolation ermittelten Anstieg bis etwa 1970. Das errechnete (max.) durchschnittliche Sterbealter der Siliko-Tuberkulose-Kranken beträgt dann 66,0 Jahre, das der Silikose-Kranken 67,5 Jahre. Die Ursachen des Anstieges wurden diskutiert. Außerdem wurde die zeitliche Änderung des durchschnittlichen Sterbealters ermittelt, die mehrere aus dem einfachen Streubereich herausfallende Werte ergab. Für diese Werte boten sich naheliegende Erklärungen an. Durch die Regressionsanalysen und die Bestimmung der zeitlichen Änderung des durchschnittlichen Sterbealters wurden Bezugspunkte gewonnen, die sich bei der Untersuchung von Detail-Entwicklungen als brauchbar erweisen könnten, so bei der Analyse der zur Zeit geübten, aber auch einer gegebenefalls geänderten Chemotherapie.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Space science reviews 4 (1965), S. 709-736 
    ISSN: 1572-9672
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Summary The general features of the solar particle composition now seem to be clear. The two most abundant components, protons and helium nuclei, have different velocity spectra, similar, but not exactly identical rigidity spectra, and varying relative abundances. The multiply charged nuclei, on the other hand, appear to have the same spectral shape and relative abundances each time measurements are made, at least in the region from 42 to 135 MeV/nucleon. Further, these relative abundances seem to reflect those of the solar atmosphere insofar as comparison can be made. Electrons are rare, but high energy electrons are not expected to be plentiful due to the probable high rate of energy loss caused by synchrotron radiation at the sun. Energetic neutrons were also not expected in large quantity and have not been observed. Finally, there is positive evidence that very small quantities of deuterons exist, probably in an amount which is about 10-3 or less of the proton abundance. The experimental data indicate that the propagation phenomenon is not purely rigidity dependent. Although the propagation of solar particles is still not well understood, the development of theories which take into account both the general magnetic field and the inhomogeneities in the field seem to hold some promise of explaining the experimental results. The composition data have also established important restraints which any acceleration theory must satisfy, and thereby contributed greatly to the very difficult problem of determining the acceleration mechanism. The similarity of the relative abundance of the energetic solar particles and the nuclei in the sun's photosphere suggested the possibility of having a new means of estimating the solar neon and helium abundances. This very interesting possibility will have to be explored by further testing of the composition of future solar particle events. Finally, it was seen that the composition was a very strong argument against most stars being the principal source of high energy non-solar cosmic rays, and, therefore, special sources, such as supernovae or possibly quasistellar objects, should be considered as much more likely prospects for the origin of cosmic rays. The results which have been obtained thus far on the composition of solar cosmic rays have indicated that further research in this area of study should be very rewarding and of value to many fields of physics. Further data on the composition and relative, as well as absolute, energy spectra of the various components are needed throughout many events. More experiments also should be performed to determine the properties of the rare components, deuterons, tritons, He3 nuclei, electrons, neutrons, and the heavier nuclei. When these experiments are complete, the knowledge which is needed to aid in answering the solar and astrophysical problems discussed in this review should be at hand.
    Materialart: Digitale Medien
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