79,450 research outputs found
The Alpha-Helix Concept: Innovative utilization of the Space Station Program. A report to the National Aeronautical and Space Administration requesting establishment of a Sensory Physiology Laboratory on the Space Station
A major laboratory dedicated to biological-medical research is proposed for the Space Platform. The laboratory would focus on sensor physiology and biochemistry since sensory physiology represents the first impact of the new space environment on living organisms. Microgravity and the high radiation environment of space would be used to help solve the problems of prolonged sojourns in space but, more importantly, to help solve terrestrial problems of human health and agricultural productivity. The emphasis would be on experimental use of microorganisms and small plants and small animals to minimize the space and time required to use the Space Platform for maximum human betterment. The Alpha Helix Concept, that is, the use of the Space Platform to bring experimental biomedicine to a new and extreme frontier is introduced so as to better understand the worldly environment. Staffing and instrumenting the Space Platform biomedical laboratory in a manner patterned after successful terrestrial sensory physiology laboratories is also proposed
Transient radiative energy transfer in incompressible laminar flows
Analysis and numerical procedures are presented to investigate the transient radiative interactions of nongray absorbing-emitting species in laminar fully-developed flows between two parallel plates. The particular species considered are OH, CO, CO2, and H2O and different mixtures of these. Transient and steady-state results are obtained for the temperaure distribution and bulk temperature for different plate spacings, wall temperatures, and pressures. Results, in general, indicate that the rate of radiative heating can be quite high during earlier times. This information is useful in designing thermal protection systems for transient operations
Dynamics of Uniform Quantum Gases, I: Density and Current Correlations
A unified approach valid for any wavenumber, frequency, and temperature is
presented for uniform ideal quantum gases allowing for a comprehensive study of
number density and particle-current density response functions. Exact
analytical expressions are obtained for spectral functions in terms of
polylogarithms. Also, particle-number and particle-current static
susceptibilities are presented which, for fugacity less than unity,
additionally involve Kummer functions. The wavenumber and temperature dependent
transverse-current static susceptibility is used to show explicitly that
current correlations are of a long range in a Bose-condensed uniform ideal gas
but for bosons above the critical temperature and for Fermi and Boltzmann gases
at all temperatures these correlations are of short range. Contact repulsive
interactions for systems of neutral quantum particles are considered within the
random-phase approximation. The expressions for particle-number and
transverse-current susceptibilities are utilized to discuss the existence or
nonexistence of superfluidity in the systems under consideration
Interaction of transient radiation in nongray gaseous systems
A general formulation is presented to investigate the transient radiative interaction in nongray absorbing-emitting species between two parallel plates. Depending on the desired sophistication and accuracy, any nongray absorption model from line-by-line models to the wide band model correlations can be employed in the formulation to investigate the radiative interaction. Special attention is directed to investigate the radiative interaction in a system initially at a uniform reference temperature and suddenly the temperature of the bottom plate is reduced to a lower but constant temperature. The interaction is considered for the case of radiative equilibrium as well as for combined radiation and conduction. General as well as limiting forms of the governing equations are presented and solutions are obtained numerically by employing the method of variation of parameters. Specific results are obtained for CO, CO2, H2O, and OH. The information on species H2O and OH is of special interest for the proposed scramjet engine application. The results demonstrate the relative ability of different species for radiative interactions
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