4 resultados para Air Displacement Method

em Publishing Network for Geoscientific


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The molar ratios of atmospheric gases change during dissolution in water due to differences in their relative solubilities. We exploited this characteristic to develop a tool to clarify the origin of ice formations in permafrost regions. Extracted from ice, molar gas ratios can distinguish buried glacier ice from intrasedimental ground ice formed by freezing groundwaters. An extraction line was built to isolate gases from ice by melting and trapping with liquid He, followed by analysis of N2, O2, Ar, 18O-O2 and 15N-N2, by continuous flow mass spectrometry. The method was tested using glacier ice, aufeis ice (river icing) and intrasedimental ground ice from sites in the Canadian Arctic. O2/Ar and N2/Ar ratios clearly distinguish between atmospheric gas in glacial ice and gases from intrasedimental ground ice, which are exsolved from freezing water. 615NN2 and 618OO2 in glacier ice, aufeis ice and intrasedimental ground ice do not show clear distinguishing trends as they are affected by various physical processes during formation such as gravitational settling, excess air addition, mixing with snow pack, and respiration.

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Two microbial isolates (HDB, Hydrogen-Degrading Bacteria) obtained from industrial wastewater were inoculated into the rotating biofilter reactor 'Biowheel 2.0' and tested for the ability to purify gaseous flows containing benzene and non-methane volatile organic compounds (NMVOCs) released at an industrial plant. Different classes of gaseous flow were tested, namely 'cold box', 'in shell', and 'mix', all of them associated with the industrial process of 'mold-casting'. A significant increase in Removal Efficiency (RE) was recorded for benzene and NMVOCs in the inoculated 'Biowheel 2.0' biofilter, compared to uninoculated control. For each type of gaseous flow, odor impact was evaluated in the inlet and outlet flows at the industrial plant, using the test panel method and electronic nose technology. A significant drop in the amount of Olfactometric Units (O.U.) m-3 occurred in the gaseous flows treated with the bacterial consortium. The reported data demonstrate the ability of the consortium to degrade hydrocarbons, revealing its potential for bioremediation of polluted air emissions occurring at industrial plants.

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The research vessel and supply icebreaker POLARSTERN is the flagship of the Alfred-Wegener-Institut in Bremerhaven (Germany) and one of the infrastructural pillars of German Antarctic research. Since its commissioning in 1982, POLARSTERN has conducted 30 campaigns to Antarctica (157 legs, mostly austral summer), and 29 to the Arctic (94 legs, northern summer). Usually, POLARSTERN is more than 300 days per year in operation and crosses the Atlantic Ocean in a meridional section twice a year. The first radiosonde on POLARSTERN was released on the 29th of December 1982, two days after POLARSTERN started on its maiden voyage to the Antarctic. And these daily soundings have continued up to the present. Due to the fact that POLARSTERN has reliably and regularly been providing upper air observations from data sparse regions (oceans and polar regions), the radiosonde data are of special value for researchers and weather forecast services alike. In the course of 30 years (1982-12-29 to 2012-11-25) a total of 12378 radiosonde balloons were started on POLARSTERN. All radiosonde data can now be found here. Each dataset contains the directly measured parameters air temperature, relative humidity and air pressure, and the derived altitude, wind direction and wind speed. 432 datasets additionally contain ozone measurements.

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This synthesis dataset contains records of freshwater peat and lake sediments from continental shelves and coastal areas. Information included is site location (when available), thickness and description of terrestrial sediments as well as underlying and overlying sediments, dates (when available), and references.