GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 233 (1971), S. 614-615 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The raw krypton samples were purified by removal of the oxygen in a magnesium furnace, and their activity was measured in a small gas proportional counter, of sensitive volume 11 cm3, surrounded by a lead shield 10 cm thick; a plastic scintillator was used as an anticoincidence counter. The ...
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Pure and applied geophysics 106-108 (1973), S. 1352-1360 
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract Stratospheric profiles of CH4 and H2 over eastern Texas have been derived up to 31 km altitude from air samples collected aboard a balloon and analyzed by gas chromatography. For H2, contamination during flight and measurement presented a problem which has been resolved only recently. The earlier profiles require corrections which are rather large for the highest altitudes. The three profiles indicate an increase of the H2 concentration in the lower stratosphere from about 0.5 p.p.m. per volume at the tropopause to about 0.8 p.p.m. at around 27 km altitude. Above that altitude the H2 concentration decreases again. An air sample collected between 44 and 62 km by a rocket-borne cryogenic sampler had an H2 concentration of 0.4 p.p.m. The five CH4 profiles showed a decrease in CH4 concentration with altitude generally with a steeper gradient directly above the tropopause and a weaker gradient at higher altitudes reaching 0.9 p.p.m. at 30 km altitude. The CH4 concentration in the rocket sample was 0.25 p.p.m., in good agreement with the gradient obtained from the balloon samples.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-0662
    Keywords: Nonmethane hydrocarbons ; trace gases ; remote troposphere ; vertical and latitudinal variation ; vertical transport ; aircraft observation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Meridional cross sections of the concentration of light hydrocarbons are reported. They were obtained from 20. April to 10. May, 1980, during the French research flight STRATOZ II, and cover the latitudes between 60° N and 60° S and the altitudes between 800 mb and 200 mb. The mixing ratios of ethane, ethene, acetylene, propane, propene, n-butane, i-butane, n-pentane, and i-pentane range between 2.0 and 0.02 ppb. Globally, a decrease in concentration with increasing altitude and -in most cases-with decreasing latitude is observed. In addition the 2-dimensional concentration fields show structures of different scales. In particular, isolated maxima of high concentrations are found in the upper troposphere. They point to fast vertical transport between the boundary layer and the upper troposphere. In the present case these maxima seem to be correlated with large scale meteorological systems, such as low pressure regions or the Inter Tropical Convergence Zone. It is argued that the NMHC provide a set of tracers well suited to the detection of fast vertical transport.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-0662
    Keywords: OH-radicals ; troposphere ; long path absorption spectroscopy ; sensitivity study ; formaldehyde ; measurements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Using long path UV absorption spectroscopy we have measured OH concentrations close to the earth's surface. The OH values observed at two locations in Germany during 1980 through 1983 range from 0.7×106 to 3.2×106 cm-3. Simultaneously we measured the concentrations of O3, H2O, NO, NO2, CH4, CO, and the light non methane hydrocarbons. We also determined the photolysis rates of O3 and NO2. This allows calculations of OH using a zero dimensional time depdendent model. The modelled OH concentrations significantly exceed the measured values for low NO x concentrations. It is argued that additional, so far unidentified. HO x loss reactions must be responsible for that discrepancy.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of atmospheric chemistry 3 (1985), S. 341-361 
    ISSN: 1573-0662
    Keywords: Peroxyradicals ; NO2 ; in-situ measurement ; matrix isolation ; electron spin resonance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract A cryogenic system for the airborne and ground based sampling of ambient radicals by matrix isolation is described. The trapped radicals, e.g., NO2 and RO2, are analyzed by ESR. The technique has been improved, mainly by addition of water vapor to the sampled air, to yield a collection efficiency of (90±10)% and a lower detection limit of about 20 ppt, but it still does not distinguish between the different RO2. Careful calibration reduced the measurement error (1 σ) to ±10% for NO2 and ±15% for HO2. Two diurnal variations of RO2 and NO2 at ground level and vertical profiles in the lower troposphere are presented.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...