ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Weitere Quellen  (78)
  • 2020-2022  (1)
  • 2005-2009  (35)
  • 1985-1989  (42)
  • 1955-1959
  • 1
    facet.materialart.
    Unbekannt
    Miniaturized system of a gas chromatograph coupled with a Paul ion trap mass spectrometer (2005)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-24
    Beschreibung: Miniature gas chromatography (GC) and miniature mass spectrometry (MS) instrumentation has been developed to identify and quantify the chemical compounds present in complex mixtures of gases. The design approach utilizes micro-GC components coupled with a Paul quadrupole ion trap (QIT) mass spectrometer. Inherent to the system are high sensitivity, good dynamic range, good QIT resolution, low GC flow-rates to minimize vacuum requirements and the need for consumables; and the use of a modular approach to adapt to volatile organic compounds dissolved in water or present in sediment. Measurements are reported on system response to gaseous species at concentrations varying over four orders of magnitude. The ability of the system to deal with complicated mixtures is demonstrated, and future improvements are discussed. The GC/QIT system described herein has a mass, volume and power that are, conservatively, one-twentieth of those of commercial off-the-shelf systems. Potential applications are to spacecraft cabin-air monitoring, robotic planetary exploration and trace-species detection for residual gas analysis and environmental monitoring.
    Schlagwort(e): Life Sciences (General)
    Materialart: Journal of mass spectrometry : JMS (ISSN 1076-5174); Volume 40; 1; 36-42
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unbekannt
    Phosphorus in foraminiferal sediments from North Atlantic Ridge cores and in pure limestones (1987)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-24
    Beschreibung: Samples of foraminiferal ooze from two North Atlantic cores were cleaned and progressively dissolved. Most of the P, Fe, and Mn was released during the first of two reductive cleaning steps. Most of the remainder of these elements and most of the Ca were released during the final acid dissolution step. The P in these samples is present largely in Fe- and Mn-rich coatings, not as a constituent of the foraminiferal shells themselves. Our results are consistent with those of earlier studies. The concentration of P in carbonate oozes in which it is clearly associated with coatings is similar to that of modern calcareous sediments in general, and with that of reasonably pure limestones of all ages. Phosphorus is apparently associated with (Fe, Mn)-oxide coatings in many carbonate sediments. The rate of removal of P from the oceans as a constituent of such sediments depends on the rate of formation of (Fe, Mn) coatings, not on the rate of incorporation of P into calcium carbonate.
    Schlagwort(e): Exobiology
    Materialart: Geochimica et cosmochimica acta (ISSN 0016-7037); Volume 51; 1861-6
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unbekannt
    Paleosols and the chemical evolution of the atmosphere (1986)
    In:  CASI
    Details
    Publikationsdatum: 2006-02-14
    Beschreibung: The chemistry and mineralogy of soils reflects the chemistry of the atmosphere below which they develop. Today the presence of a cover of land plants can obscure the signature of a highly oxidizing atmosphere. Prior to the advent of higher land plants ca. 400 m.y. ago the obscuring effect of a biological interface should have been minor. It can be shown that under such conditions the behavior of ferrous iron during weathering depends on the relationship between the ratio of the net concentration of oxidants to the concentration of acids in rainwater, and on the ratio of the oxygen demand to the acid demand for complete weathering of the parent rock. An analysis of the behavior of iron in some 15 paleosols between 1.0 and 2.9 b.y. in age showed some time ago that iron was retained, or largely retained, in paleosols developed on rocks with a low ratio of oxidant demand to acid demand (R value) and was lost from paleosols with a high R value. The results indicate that between 1.1 and 2.9 b.y.b.p. the ratio of the net concentration of oxidants to CO2 in rainwater was less than ca. 1/600 of the present-day value. Work during the past year has sought to extend the data base for paleosols and to define more precisely the relationships between the composition of paleosols and the chemistry of the atmosphere below which they developed.
    Schlagwort(e): SPACE BIOLOGY
    Materialart: NASA, Washington Second Symposium on Chemical Evolution and the Origin and Evoltuion of Life; p 68
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unbekannt
    Productivity issues at organizational interfaces (1985)
    In:  CASI
    Details
    Publikationsdatum: 2006-02-14
    Beschreibung: The need for close interdependence between large numbers of diverse and specialized work groups makes the Space Program extremely vulnerable to loss of productivity at organizational interfaces. Trends within the program also suggest that the number and diversity of interfaces will grow in the near term. Continued maintenance of R&D excellence will require that interface performance issues be included in any future productivity improvement effort. The types and characteristics of organizational interfaces are briefly presented, followed by a review of factors which impact their productivity. Approaches to assessing and improving interface effectiveness are also discussed.
    Schlagwort(e): ADMINISTRATION AND MANAGEMENT
    Materialart: NASA. Johnson (Lyndon B.) Space Center R and D Productivity: New Challenges for the US Space Program; p 109-119
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unbekannt
    An improved rocket ozonesonde (ROCOZ-A). II - Preparation of stratospheric ozone profiles (1986)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-19
    Beschreibung: The ROCOZ-A radiometer measures ozone by long pathlength photometry in the stratosphere and lower mesosphere. After a rocket launch to an apogee of 70 km, the instrument measures the solar ultraviolet irradiance over its four filter wavelengths as it descends on a parachute. The fundamental values from ROCOZ-A are ozone overburdens versus radar altitude from 53 to 20 km. The slope of these values gives ozone number density. At one standard deviation the repeatability of the ozone overburden measurements averages 2.4 percent. For ozone number density the repeatability averages 3.2 percent with a significant increase at altitudes below the ozone number density maximum. The accuracy limits for overburden and number density are estimated at 5-7 percent. With auxiliary measurements of pressure and temperature, ozone results are also produced in terms of ozone mixing ratio, albeit with a slight broadening of the estimated accuracy limits. The vertical response of ROCOZ-A ozone measurements (full width at half maximum) is 4 km. The assembly of ROCOZ-A profiles can be used to compare with measurements from each of the current NASA and NOAA satellite ozone instruments. In addition, the repeatability of ROCOZ-A allows the use of this instrument as a transfer standard between satellite instruments with different fundamental ozone measurements.
    Schlagwort(e): GEOPHYSICS
    Materialart: Journal of Geophysical Research (ISSN 0148-0227); 91; 14521-14
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unbekannt
    Results from the Balloon Ozone Intercomparison Campaign (BOIC) (1985)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-19
    Beschreibung: In the Balloon Ozone Intercomparison Campaign (BOIC), several in situ UV absorption photometers, two solar UV absorption photometers, electrochemical sondes, and a mass spectrometer were intercompared in three flight missions. Concurrent data from Umkehr and satellite observations are also intercompared. The National Bureau of Standards provided a 'standard' ozone source for intercomparing the in situ instruments and ground pressure. Preliminary findings indicate that the standard deviation of the sensitivities among 17 instruments against the NBS reference was about 11 percent. These differences appear in flight at the lower levels and change at higher altitudes, indicating height-dependent errors. The difference among five in-situ UV photometers flown together ranged by plus or minus 8 percent during ascent to about 41 km. During float at 42 km, the difference nearly doubled. During descent, the difference decreased to about 4 percent, which is much closer to the expected accuracy of these instruments. Results from UV solar radiometers have been systematically higher than those from UV photometers by 15 to 20 percent - a very important disagreement that needs to be resolved.
    Schlagwort(e): GEOPHYSICS
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unbekannt
    Equatorial ozone profiles from the ground to 52 km during the Southern Hemisphere autumn (1987)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-19
    Beschreibung: The results of an ozone measurement campaign conducted at Natal, Brazil from March 25 to April 15, 1985 are reported. Complete profiles of ozone, pressure, and temperature were obtained from the ground to 52 km, and all of the profiles correspond with site overpasses by ozone instruments on NASA and NOAA satellites. The profiles from this measurement series show reasonable agreement with established satellite climatologies. Stratospheric ozone variability was 2 percent or less during the 3 weeks of the measurement campaign, with stratospheric temperature and pressure variabilities half that amount. Low variability at a single location for this period implies comparable uniformity for ozone profiles over a large area around the measurement site. The auxiliary pressure and temperature profiles presented here allow the use of this data set as a transfer standard between satellite instruments with different fundamental ozone measurements. Finally, the low ozone variability in the stratosphere at Natal during this measurement series should provide an opportunity for high-quality intercomparisons of measured and modeled ozone concentrations in the equatorial stratosphere and lower mesosphere as well as a consistency check among satellite ozone measurements.
    Schlagwort(e): GEOPHYSICS
    Materialart: Journal of Geophysical Research (ISSN 0148-0227); 92; 5573-558
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 8
    facet.materialart.
    Unbekannt
    Optical emission from coupled surface plasmons (1987)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-19
    Beschreibung: Surface plasmons on opposite sides of a thin metal film surrounded by identical dielectrics interact to form coupled surface plasmons (CSP's). Corrugation of the metal film permits interaction of the CSP's with the radiation field. This paper reports the observation of optical emission from CSP's excited by the near-field coupling of molecules adjacent to a corrugated thin metal film embedded in photoresist.
    Schlagwort(e): SOLID-STATE PHYSICS
    Materialart: Optics Letters (ISSN 0146-9592); 12; 364-366
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 9
    facet.materialart.
    Unbekannt
    The AMPTE Charge Composition Explorer science data system (1985)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-19
    Beschreibung: The instrument complement on all three Active Magnetospheric Particle Tracer Explorer (AMPTE) spacecraft is devoted to the conduction of the unified measurements which are required to achieve the scientific aims. A single science data base for each spacecaft has, therefore, been established with the objective to facilitate unified analysis. The data are kept in Science Data Centers in the U.S., West Germany, and the United Kingdom. The Science Data Center dedicated to the Charge Composition Explorer (CCE) is located at the Applied Physics Laboratory of Johns Hopkins University where it was developed. The present paper is concerned with aspects of the computing center's design, development and operations.
    Schlagwort(e): GROUND SUPPORT SYSTEMS AND FACILITIES (SPACE)
    Materialart: IEEE Transactions on Geoscience and Remote Sensing (ISSN 0196-2892); GE-23; 212-215
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unbekannt
    Thermionic fuel element technology status (1985)
    In:  Other Sources
    Details
    Publikationsdatum: 2011-08-19
    Beschreibung: The results of research, conducted between the mid-1960s and 1973, on the multiconverter thermionic fuel elements (TFEs) that comprise the reactor core of an SP-100 thermionic reactor system are presented. Fueled-emitter technology, insulator technology and cell and TFE assembly technology of the prototypical TFEs which were tested in-pile and out-of-pile during these years are described. The proto-TFEs have demonstrated reproducible performance within 5 percent and no premature failures within the 1.5 yr of operation (with projected 3-yr lifetimes). The two primary life-limiting factors had been identified as thermionic emitter dimensional increase due to interactions with the fuel and electrical insulator structural damage from fast neutrons. Multiple options for extending TFE lifetimes to 7 yr or longer are available and will be investigated in the 1984-1985 SP-100 program for resolution of critical technology issues. Design diagrams and test graphs are included.
    Schlagwort(e): ENERGY PRODUCTION AND CONVERSION
    Format: text
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    NASA TECHNICAL REPORTS
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...