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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 145 records · Page 8

Calibrated VLF phase measurements: Simultaneous remote and local measurements of 10.2kHz carrier phase using cesium standards

An investigation of spatial irregularity of VLF phase due to nearby objects and terrain is discussed. It is shown that the phase is regular to the microsecond accuracy of the instrumentation, and that a grounded steel tower in close proximity to a whip antenna will not affect the phase measurement. However, antennas coupling to trees may cause an anomalous phase shift.

Swanson, E. R.↗

Comparison of ozone measurement techniques using aircraft, balloon, and ground-based measurements

In order to verify the ultraviolet absorption technique used in the Global Atmospheric Sampling Program, two flight experiments were conducted employing several techniques, both in situ and remote, for measuring atmospheric ozone. The first experiment used the NASA CV-990 equipped with an ultraviolet absorption ozone monitor and an ultraviolet spectrophotometer, a balloon ozonesonde, and a Dobson station for determining and comparing the ozone concentration data. A second experiment compared ozone data from an automated sampling system aboard a B-747 with data from a manned system installed on the NASA CV-990 during a cross-country flight with both aircraft following the same flight path separated by 32 kilometers.

Briehl, D.↗

Measurements in the Turbulent Boundary Layer at Constant Pressure in Subsonic and Supersonic Flow. Part 2: Laser-Doppler Velocity Measurements

A description of both the mean and the fluctuating components of the flow, and of the Reynolds stress as observed using a dual forward scattering laser-Doppler velocimeter is presented. A detailed description of the instrument and of the data analysis techniques were included in order to fully document the data. A detailed comparison was made between the laser-Doppler results and those presented in Part 1, and an assessment was made of the ability of the laser-Doppler velocimeter to measure the details of the flows involved.

Dimotakis, P. E.↗

Infrared measurements of stratospheric composition. II - Simultaneous NO and NO2 measurements

A further flight of the balloon-borne pressure-modulated radiometer (PMR) instrument (Chaloner et al., 1978) is described when simultaneous measurements of NO and NO2 concentrations were made through dawn. A detailed description of the retrieval methods used and the precautions taken against interference from signals from the other gases is given. Profiles of NO(x) through dawn are also briefly considered

Drummond, J. R.↗