Microgravity effects

Naumann, R. J. Mason, E. D. Summaries of Early Materials Processing in Space, NASA TM-78240, Aug. 1979. More recent experiments that provide excellent data on microgravity effects with fluids can be found in the accompanying preprints from this symposium. 

Because of their application as electro-optic (EO) materials the appropriate choice is to measure Pockels coefficients Vy which alter the propagating characteristics of light in the medium. However, we found Vy too small for any quantitative analysis of the microgravity effects, instead, we opted to monitor the relaxation of second harmonic (SH) signal. 

Iguchi M, Terauchi Y (2001) Microgravity effects on the rising velocity of bubbles and slugs in vertical pipes of good and poor wettability, Int. J. Multiphase Flow 27 2189-2198... 

Reed Justin A, Andrew C, Halaas HJ, Paul P, Alex R, Thomas MJ, Grieser F (2003) The effects of microgravity on nanoparticle size distributions generated by the ultrasonic reduction of an aqueous gold-chloride solution. Ultrason Sonochem 10(4—5) 285-289... 

Rotating culture vessels such as simulated microgravity systems are primarily used to study 3-D tumor growth and differentiation. However, mixed cell populations combined with matrix proteins can be used to generate a complex microenvironment in which cell-cell interactions and invasion can be measured (95). A similar system has also been described for the coculture of endothelial cells, myofibroblasts, and tumor cell clusters embedded in Matrigel . Differential labeling of the cell populations enables their invasion and the effects of inhibitors to be measured (96). 

Voorhees s experimental study of low-volume-fraction-solid liquid+solid Pb-Sn mixtures carried out under microgravity conditions during a space shuttle flight enabled a wider range of solid-phase volume fractions to be studied without significant influence of buoyancy (flotation and sedimentation) effects [13]. The rate of approach to the steady-state particle-size distribution in 0.1-0.2 volume-fraction... 

Working in partnership with the scientific community and commercial industry. NASA s Microgravity Research Program strives to increase understanding of the effects of gravity on biological, chemical and physical systems. 

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