Rothermel, H., Käufl, H. U., Schrey, U., & Drapatz, S. (1988). Thermal structure of the Martian mesosphere. A&A, 196, 296–300.
Keywords: atmospheric temperature, carbon dioxide, infrared spectroscopy, mars atmosphere, mesosphere, emission spectra, line spectra, spatial resolution, mars, atmosphere, mesosphere, structure, thermal properties, spectra, spectroscopy, earth-based observations, temperature, patterns, infrared, polar regions, wavelengths, equipment, procedure, carbon dioxide, emissions
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Aberle, N., & Witte, U. (2003). Deep-sea macrofauna exposed to a simulated sedimentation event in the abyssal NE Atlantic: in situ pulse-chase experiments using 13C-labelled phytodetritus. Mar Ecol Prog Ser, 251, 37–47.
Abstract: Tracer experiments with 13C-labelled diatoms Thalassiosira rotula (Bacillariophycea, 98% 13C-labelled) were conducted at the Porcupine Abyssal Plain (PAP) in the NE Atlantic (BENGAL Station; 48<b0>50'N, 16<b0>30'W, 4850 m depth) during May/June 2000. In situ enrichment experiments were carried out using deep-sea benthic chamber landers: within the chambers a spring bloom was simulated and the fate of this food-pulse within the abyssal macrobenthic community was followed. In focus was the role of different macrofauna taxa and their vertical distribution within the sediment column in consuming and reworking the freshly deposited material. T. rotula is one of the most abundant pelagic diatoms in the NE Atlantic and therefore 0.2 g of freeze dried T. rotula, equivalent to 1 g algal C m-2 yr-1, was injected into each incubation chamber. Three different incubation times of 2.5, 8 and 23 d were chosen in order to follow the uptake of 13C-labelled phytodetritus by macrofauna. After only 2.5 d, 77% of all macrofauna organisms showed tracer uptake. After 23 d the highest degree of enrichment was measured and 95% of the individuals had taken up 13C from the introduced algal material. In addition to that a downward transport of organic matter was observed, even though the mixing was not very intense. The initial processing of carbon was dominated by polychaetes that made up a percentage of 52% of total macrofauna. In general macrofauna organisms that lived close to the sediment surface had higher access to the simulated food-pulse, confirming the hypothesis that individuals close to the sediment surface have the strongest impact on the decomposition of phytodetritus. In our study we observed only modest vertical entrainment of 13C tracers into the sediment. With regard to contradictory results from former 13C-enrichment experiments in bathyal regions, compared to results from our study site in the abyssal plain, we thus propose pronounced differences in feeding strategies between macrofauna communities from continental margins and abyssal plains.
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Skalare, A., McGrath, W. R., Echternach, P. M., Leduc, H. G., Siddiqi, I., Verevkin, A., et al. (2001). Aluminum hot-electron bolometer mixers at submillimeter wavelengths. IEEE Trans. Appl. Supercond., 11(1), 641–644.
Abstract: Diffusion-cooled aluminum hot-electron bolometer (HEB) mixers are of interest for low-noise high resolution THz-frequency spectroscopy within astrophysics. Al HEB mixers offer operation with an order of magnitude less local oscillator power, higher intermediate frequency bandwidth and potentially lower noise than competing devices made from other materials. We report on mixer experiments at 618 GHz with devices fabricated from films with sheet resistances in the range from about 55 Ω down to about 9 Ω per square. Intermediate frequency bandwidths of up to 3 GHz were measured (1 μm long device), with absorbed local oscillator power levels of 0.5 to 6 nW and mixer conversion up to -21.5 dB. High input coupling efficiency implies that the electrons in the device are able to thermalize before escaping from the device. It was found that the long coherence length complicates mixer operations due to the proximity of the contact pads. Also, saturation at the IF frequency may be a concern for this type of device, and warrants further studies.
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de Graauw, T., Caux, E., Guesten, R., Helmich, F., Pearson, J., Phillips, T. G., et al. (2005). The Herschel-heterodyne instrument for the far-infrared (HIFI). In Bulletin of the American Astronomical Society (1219). Bulletin of the American Astronomical Society, 37.
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Johnson, M. A., Betz, A. L., McLaren, R. A., Townes, C. H., & Sutton, E. C. (1976). Nonthermal 10 micron CO2 emission lines in the atmospheres of Mars and Venus. A&A, 208, 145.
Keywords: carbon dioxide, emission spectra, infrared spectra, mars atmosphere, nonthermal radiation, optical heterodyning, planetary radiation, venus atmosphere, absorption spectra, energy transfer, line spectra, molecular absorption, molecular collisions, near infrared radiation, solar flux
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