The effects of magnetic field on the growth process of protein crystals is an attractive topic since it may provide a new means in addition to microgravity condition to produce protein crystals of higher quality than in the normal case. In this paper, we present our recent efforts to study the mechanisms of the protein crystal growth under a strong magnetic field. Contrary to all of the previous studies concerning magnetic field in which only diamagnetic materials were used as crystallization agents, this paper demonstrates another salt, NiCl₂, which is a paramagnetic material, as a crystallizing agent. The morphologies of the crystals both inside and outside of the magnetic field were studied. It was found that the crystals grown with NiCl₂ showed large variety of morphologies depending on the growth conditions. Furthermore, it was concluded that magnetic field can substantially affect the crystal morphology.

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This paper describes the ground-based vacuum electrostatic levitation furnace (ELF) developed as a breadboard model for the flight facility for the International Space Station (ISS). It first discusses the importance of containerless processing for material science, then describes the sample position and rotation control methods, and one of the most significant applications to the ELF, thermophysical property measurements.

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As one of key technologies for In-Situ Resource Utilization (ISRU), combustion synthesis has been proposed. Influences of environmental factors of gravity and pressure on a combustion synthesis process using iron oxide and aluminum powders, i.e., thermite reaction, are investigated by reaction propagation rate measurements and qualitative analyses in the present work. The gravity environments are normal (1G) and microgravitational (μG) that is prepared at a drop tower facility, and pressure environments are “low” at -200Pa and normal with argon gas at 1x10^-1MPa. For the reactants, iron oxide of -50μm is used and three kinds of aluminum powders are prepared varying their particle size between -40μm and -160μm. As a result, it is confirmed that combustion synthesis has applicability to ISRU with appropriate powder selection. The reaction propagation rate under μG is smaller than that under 1G, comparing the rate for the 50μm aluminum. On the other hand, using 40μm aluminum under μG, the rates are largely scattered in both pressure conditions. Qualitative analysis shows the completion of reaction, excepting the case of 160μm in low pressure under normal gravity. It is found that hercynite is produced and it would be produced more under low pressure than under normal pressure.

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We fabricate 128-Kbit SRAMS using rad-hard circuit design based on a mixed mode 3D-simulation in a commercial SOI foundry with 0.2 μm design rules. Appropriate design increases the critical LET of single-event-upset to 45 MeV/(mg/cm²). The upset rate for the SRAM installed in equipment in a GEO orbit (M=7) is estimated to be 3.1x10^-7 upsets/device-day, which is quite an acceptable SEU hardness.

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Atomic oxygen (AO) in low earth orbit environment causes significant physical sputtering and/or chemical changes in most materials particularly in polymeric systems. In this review, five major techniques utilized to date to protect AO attacks in polymeric substances have been described. Surface coatings, compounding, compositing, use of novel homopolymers or copolymers, and polymer blending are discussed. AO protection by surface coatings is predominantly used in current space industry due to its ease of fabrication with minor modification to the existing polymers. Durability and uniformity of the coating surface as well as substantial adhesion between the core and the coating skin are critical for the success or failure of this technique. The modifications of polymeric systems by compounding or compositing yield marginal improvement in AO protection depending mainly upon types of fillers used whereas the syntheses of novel AO resistant polymers based on stable atoms such as fluorine, silicon, or phosphorus are actively pursued and proposed with some reported commercial success. In addition, AOR Kapton manufactured by DuPont is one example of utilizing miscible polymer blend systems for AO protection in polymers. The utilization of phase-separated polymer blends to yield protective skin layers which are Si-rich or P-rich may render another prospective way for AO protection in extensively space-utilized polyimide systems. By controlling the discrepancy in the blend-pair affinity, layered phase separation may be induced. Overall properties of core polyimide are expected to remain unchanged due to the relatively low quantity of the skin layer material used i.e. in the range of few percent by weight.

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