A generalized correlation of experimental flat-plate collector performance

A generalized collector performance correlation was derived and shown by experimental verification to be of the proper form to account for the majority of the variable conditions encountered both in outdoor and in indoor collector tests. This correlation permits a determination of collector parameters which are essentially nonvarying under conditions which do vary randomly (outdoors) or conditions which vary in a controlled manner (indoors - simulator). It was shown that correlation of the experimental performance of collectors allows the following: (1) comparisons of different collector designs; (2) collector performance prediction under conditions that differ from the conditions of the test program; and (3) monitoring performance degradation effects

Flat plate collector performance determined experimentally with a solar simulator

The NASA is constructing a new office building at Langley Research Center that will utilize solar energy for heating and cooling. A collector technology program being conducted at Lewis will provide the basis for selecting collectors for use at Langley. The technology program includes testing collectors in an indoor facility under simulated solar radiation. Tests have been conducted on five collectors to date and performance data are presented herein

Galactic dust polarized emission at high latitudes and CMB polarization

We estimate the dust polarized emission in our galaxy at high galactic latitudes, which is the dominant foreground for measuring CMB polarization using the high frequency instrument (HFI) aboard Planck surveyor. We compare it with the level of CMB polarization and conclude that, for angular scales $\le 1^{\circ}$, the scalar-induced CMB polarization and temperature-polarization cross-correlation are much larger than the foreground level at $\nu \simeq 100 GHz$. The tensor-induced signals seem to be at best comparable to the foreground level.}Comment: Latex document, 4 pages, 2 figures, to appear in "Fundamental parameters in Cosmology", Rencontres de Moriond, 199

Rapid linear pyrolysis of composite solid propellant ingredients Final report

Rapid linear pyrolysis of thermoplastic solid fuels by intense heat flux levels to simulate combustio

Role of the surface in the measurement of the Leidenfrost temperature

Role of surfaces in measuring Leidenfrost temperatur

[CII] 158μ\mum and [NII] 205μ\mum emission from IC 342 - Disentangling the emission from ionized and photo-dissociated regions

Aims: We investigate how much of the [CII] emission in the nucleus of the nearby spiral galaxy IC 342 is contributed by PDRs and by the ionized gas. We examine the spatial variations of starburst/PDR activity and study the correlation of the [CII] line with the [NII] 205{\textmu}m emission line coming exclusively from the HII regions. Methods: We present small maps of [CII] and [NII] lines recently observed with the GREAT receiver on board SOFIA. In particular we present a super-resolution method to derive how unresolved, kinematically correlated structures in the beam contribute to the observed line shapes. Results: We find that the emission coming from the ionized gas shows a kinematic component in addition to the general Doppler signature of the molecular gas. We interpret this as the signature of two bi-polar lobes of ionized gas expanding out of the galactic plane. We then show how this requires an adaptation of our understanding of the geometrical structure of the nucleus of IC~342. Examining the starburst activity we find ratios $I([CII])/I(^{12}\mathrm{CO} (1-0))$ between 400 and 1800 in energy units. Applying predictions from numerical models of HII and PDR regions to derive the contribution from the ionized phase to the total [CII] emission we find that 35-90% of the observed [CII] intensity stems from the ionized gas if both phases contribute. Averaged over the central few hundred parsec we find for the [CII] contribution a HII-to-PDR ratio of 70:30. Conclusions: The ionized gas in the center of IC 342 contributes more strongly to the overall [CII] emission than is commonly observed on larger scales and than is predicted. Kinematic analysis shows that the majority of the [CII] emission is related to the strong but embedded star formation in the nuclear molecular ring and only marginally emitted from the expanding bi-polar lobes of ionized gas.Comment: 20 pages spectra available online: http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/ submitted to and accepted by A&