Microgravity experiment

Space shuttle -microgravity experiments [SPACE PROCESSING] (Vol 22) -use of ablative materials [ABLATIVE MATERIALS] (Vol 1) -use of high temperature alloys [HIGH TEMPERATURE ALLOYS] (Vol 13)... 

Fig. 1 Thermal dendrites grown in a microgravity experiment as part of the Isothermal Dendrite Growth Experiments (IDGE) carried out by the Renasslear Polytechnic Institute team headed by Glicksman. (Taken from the IDGE home page on http //www.rpi.edu/locker/56/000756/.)...

These results prompted a number of experiments in subsequent missions designed to measure diffusion coefficients of liquid metals. Some of these experiments found a power law dependence on temperature, with the exponent varying around 2 for different materials, while others found a better fit with an Arrhenius model. However, all of the microgravity experiments consistently measured diffusion coefficients that were 30-50% lower than the accepted values, suggesting that all existing transport data for liquid metals may be contaminated by unwanted convection. A recent analysis demonstrated the difficulty of eliminating convective transport in such measurements in normal gravity.f ... 

Stefanescu, D.M. Juretzko, F.R. Dhindaw, B.K. Catalina, A. Sen, S. Curreri, P.A. Particle engulf-ment and pushing by solidifying interfaces Part II. Microgravity experiments and theoretical analysis. Metall. Mater. Trans. A. 1998, 29A, 1697-1706. 

Schwabe, D. Scharmann, A. Microgravity Experiments on the Transition from Laminar to Oscillatory Thermocapillary Convection in Floating Zones COSPAR, Advances in Space Research Pergamon Press, to be published in 1984. 

CARINA (CApsula di RIentro Non Abitata) will be the first Italian module with re-entry capability, developed by Alenia Spazio for the National Space Agency. Scheduled for launch from the San Marco platform by means of the Super Scout rocket, it will return microgravity experiments to Earth after some days in orbit (Figure 1 ). 

Fig. 14.4 Dependence of interdroplet flow propagation speed on interdroplet spacing, measured in microgravity experiments fm a linear array of n-decane droplets in standard atmosphere [15]...

The following pages are a brief review of experiments indicative of gravitational effects on polymerizations and polymer processes. These experiments provide an insight into the types of processes that may be investigated using microgravity experiments. 

Still, however, desired to compare the gross effects of the microgravity experiment. To prevent having to deal with vacuum effects during this experiment, the experimental chamber was sealed from the rocket s external environment allowing the foam to form at approximately one atmosphere pressure. 

The microgravity experiments were carried out at ZARM Drop Tower using a 7-platform drop capsule. From bottom to top, there are (1) platform No. 

DAMNA) (Figure 1). Frazier et al (6,7) reported the surface polymerization of polydiacetylene films from the photopolymerization of DAMt A monomer solutions. This unique photopolymerization process produces amorphous thin films of polydiacetylene, which can be used in the fabrication of waveguides and photonic devices. However films formed on earth are low quality and have defects that appear to be the result of buoyancy-driven convection. Microgravity experiments on the same system produced very high quality optical films. The lack of in-situ measurements limited the analysis of the effect of gravitational forces on the development of defects in the poyldiacetylene films. 

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