ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • GEOPHYSICS  (1,591)
  • SPACECRAFT PROPULSION AND POWER  (438)
  • Physics
  • 1990-1994  (1,006)
  • 1980-1984  (1,363)
  • 1
    facet.materialart.
    Unknown
    Landau damping of auroral hiss (1994)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Auroral hiss is observed to propagate over distances comparable to an Earth radius from its source in the auroral oval. The role of Landau damping is investigated for upward propagating auroral hiss. By using a ray tracing code and a simplified model of the distribution function, the effect of Landau damping is calculated for auroral hiss propagation through the environment around the auroral oval. Landau damping is found to be the likely mechanism for explaining some of the one-sided auroral hiss funnels observed by Dynamics Explorer 1. It is also found that Landau damping puts a lower limit on the wavelength of auroral hiss. Poleward of the auroral oval, Landau damping is found in a typical case to limit omega/k(sub parallel) to values of 3.4 x 10(exp 4) km/s or greater, corresponding to resonance energies of 3.2 keV or greater and wavelengths of 2 km or greater. For equatorward propagation, omega/k(sub parallel) is limited to values greater than 6.8 x 10(exp 4) km/s, corresponding to resonance energies greater than 13 keV and wavelengths greater than 3 km. Independent estimates based on measured ratios of the magnetic to electric field intensity also show that omega/k(sub parallel) corresponds to resonance energies greater than 1 keV and wavelengths greater than 1 km. These results lead to the difficulty that upgoing electron beams sufficiently energetic to directly generate auroral hiss of the inferred wavelength are not usually observed. A partial transmission mechanism utilizing density discontinuities oblique to the magnetic field is proposed for converting auroral hiss to wavelengths long enough to avoid damping of the wave over long distances. Numerous reflections of the wave in an upwardly flared density cavity could convert waves to significantly increased wavelengths and resonance velocities.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 99; A2; p. 2471-2488
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    Electronic Resource
    Electronic Resource
    Aromatic polyamides. II. Thermal degradation of some aromatic polyamides and their model diamides (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2817-2834 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal degradation behavior of poly(1,3-phenylene isophthalamide) and poly(chloro-2,4-phenylene isophthalamide) was investigated with the aid of some appropriate model compounds. The pyrolysis products of these materials were identified by gas chromatography (GC), gas chromatography/Fourier transform infrared spectroscopy (GC/FT-IR), and gas chromatography/mass spectrometry (GC/MS). The residual chars were characterized by IR spectroscopy. Thermogravimetric analysis (TGA) was applied to study the effect of end-group concentration on the degradation characteristics of the two polyamides. Kinetic parameters that describe the thermal degradation of the polyamides were also evaluated by TGA. The results of this investigation suggest that the thermal decomposition of these aromatic polyamides involves homolytic as well as hydrolytic cleavages of the amide units.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.170191115
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Spectroscopic studies of solutions, suspensions, and precipitates of poly(1,6-di-p-toluene sulfonyloxy-2,4-hexadiyne) (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Physics Edition 19 (1981), S. 321-334 
    Details
    ISSN: 0098-1273
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Optical-absorption, fluorescence, and Raman spectra for solutions, suspensions, and precipitates of poly(1,6-di-p-toluene sulfonoxy-2,4-hexadiyne) in and from nitrobenzene, acetone, and chloroform are presented. These are interpreted in terms of the occurrence of two forms of the polymer chain; a quasicrystalline form with properties close to those of single crystal polymer and a chain-extended form occurring in solution and colloidal particles, with an absorption energy of about 2.5 eV (20,000 cm-1). No evidence is found for the presence of very short polymer chains in partially polymerized monomer at low conversion. The relationship of these results to those for deformed single crystals is briefly discussed.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.180190212
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    facet.materialart.
    Unknown
    The Koshak section: Evidence for element fractionation and an oxidation event at the K/T boundary (1993)
    In:  Other Sources
    Details
    Publication Date: 2019-01-25
    Description: The Koshak site is a new K/T section located about 125 km EEN of the Fort Shevchenko city, Mangyshlak, Kazakhstan. In this paper, we report results of geochemical and mineralogical studies of this section which indicate a deep element fractionation and an oxidation event at the K/T boundary.
    Keywords: GEOPHYSICS
    Type: Lunar and Planetary Inst., Twenty-Fourth Lunar and Planetary Science Conference. Part 3: N-Z; p 1051-1052
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Stennis Space Center's approach to liquid rocket engine health monitoring using exhaust plume diagnostics (1991)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: Details are presented of the approach used in a comprehensive program to utilize exhaust plume diagnostics for rocket engine health-and-condition monitoring and assessing SSME component wear and degradation. This approach incorporates both spectral and video monitoring of the exhaust plume. Video monitoring provides qualitative data for certain types of component wear while spectral monitoring allows both quantitative and qualitative information. Consideration is given to spectral identification of SSME materials and baseline plume emissions.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: SAE PAPER 911192
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    Correlated dynamical changes in the near-earth and distant magnetotail regions - ISEE 3 (1984)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: It is pointed out that the redeployment of ISEE 3 from its continuous monitoring of the solar wind in a large orbit about the upstream Lagrangian point to an extended magnetotail orbit has afforded an opportunity for deep-tail passage of October 1982, and in the radial range from 200 to 220 R(E) during the near-apogee part of the second tail passage in January-February 1983. Attention is given to instrumentation and data sets, spacecraft positions, and observational data.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 89; 3855-386
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    Zonal mean winds in the equatorial mesosphere and lower thermosphere observed by the High Resolution Doppler Imager (1993)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: This paper presents analyses of mesospheric and lower thermospheric zonal mean winds observed by the High Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS). Monthly averages of the equatorial zonal mean zonal winds are presented for January 1992 through June 1993. Equatorial zonal winds in the 70-90 km region are dominated by a semiannual oscillation (SAO), ranging from 30 m/s (westerly) to -100 m/s (easterly). At high latitudes the zonal wind variations are predominantly annual. Above 90 km, the low-latitude flow is easterly at all times, punctuated by a small semiannual variation. This behavior may be related to the deposition of momentum by the diurnal tides.
    Keywords: GEOPHYSICS
    Type: Geophysical Research Letters (ISSN 0094-8276); 20; 24; p. 2849-2852
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unknown
    Correlated low-frequency electric and magnetic noise along the auroral field lines (1984)
    In:  Other Sources
    Details
    Publication Date: 2019-08-13
    Description: Dynamics Explorer 1 measurements of intense low-frequency electric and magnetic noise observed at low altitudes over the auroral zone are described. The intensity of both the electric and magnetic fields decreases rapidly with increasing frequency. Most of the energy is at frequencies below the O(+) cyclotron frequency, and some evidence is found for a cutoff or change in spectral slope near that frequency. The magnetic to electric field ratio decreases rapidly with increasing radial distance and also decreases with increasing frequency. The polarization of the electric field in a plane perpendicular to the earth's magnetic field is essentially random. The transverse electric and magnetic fields are closely correlated, with the average Poynting flux directed toward the earth. The total electromagnetic power flow associated with the noise is substantial. Two general models are discussed to interpret these observations, one based on static electric and magnetic fields imbedded in the ionosphere and the other based on Alfven waves propagating along the auroral field lines.
    Keywords: GEOPHYSICS
    Type: AD-A150627 , Journal of Geophysical Research (ISSN 0148-0227); 89; 8971-898
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unknown
    Remote sensing of mesospheric winds with the High-Resolution Doppler Imager (1992)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Observations of the winds in the upper atmosphere obtained with the High-Resolution Doppler Imager (HRDI) on the Upper Atmosphere Research Satellite (UARS) are discussed. This instrument is a very stable high-resolution triple-etalon Fabry-Perot interferometer, which is used to observe the slight Doppler shifts of absorption and emission lines in the O2 Atmospheric bands induced by atmospheric motions. Preliminary observations indicate that the winds in the mesosphere and lower thermosphere are a mixture of migrating and non-migrating tides, and planetary-scale waves. The mean meridional winds are dominated by the 1,1 diurnal tide which is easily extracted from the daily zonal means of the satellite observations. The daily mean zonal winds are a mixture of the diurnal tide and a zonal flow which is consistent with theoretical expectations.
    Keywords: GEOPHYSICS
    Type: Planetary and Space Science (ISSN 0032-0633); 40; 12; p. 1599-1606.
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    Relativistic electron acceleration and decay time scales in the inner and outer radiation belts: SAMPEX (1994)
    In:  Other Sources
    Details
    Publication Date: 2011-08-24
    Description: High-energy electrons have been measured systematically in a low-altitude (520 x 675 km), nearly polar (inclination = 82 deg) orbit by sensitive instruments onboard the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX). Count rate channels with electron energy thresholds ranging from 0.4 MeV to 3.5 MeV in three different instruments have been used to examine relativistic electron variations as a function of L-shell parameter and time. A long run of essentially continuous data (July 1992 - July 1993) shows substantial acceleration of energetic electrons throughout much of the magnetosphere on rapid time scales. This acceleration appears to be due to solar wind velocity enhancements and is surprisingly large in that the radiation belt 'slot' region often is filled temporarily and electron fluxes are strongly enhanced even at very low L-values (L aprroximately 2). A superposed epoch analysis shows that electron fluxes rise rapidly for 2.5 is approximately less than L is approximately less than 5. These increases occur on a time scale of order 1-2 days and are most abrupt for L-values near 3. The temporal decay rate of the fluxes is dependent on energy and L-value and may be described by J = Ke-t/to with t(sub o) approximately equals 5-10 days. Thus, these results suggest that the Earth's magnetosphere is a cosmic electron accelerator of substantial strength and efficiency.
    Keywords: GEOPHYSICS
    Type: Geophysical Research Letters (ISSN 0094-8276); 21; 6; p. 409-412
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...