The structure of undercooling liquid state is one of the important subjects of materials science. The levitation techniques are powerful tools for the investigation of undercooled liquids. In this research, we developed the electrostatic levitation furnace for the liquid structure analysis due to the neutron and x-ray diffraction methods. The apparatus was tested by using a synchrotron radiation facility, a laboratory X-ray source and a reactor. The structures of several kinds of materials were investigated and the liquid structures can be measured with high precision.

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We propose the new containerless process, which can attain the solidification of the levitated samples by the inert gas jet flow. By this process, light rare earth-transition metal-Al alloys was analyzed with respect to the high undercooling, bulk amorphous formation. Also, Nd-Fe binary and Nd-Fe-Al ternary alloys analyzed with respects to the high coercive force depending on undercooling and the microstructure of metastable phase. La-Cu-Ni-Co-Al alloys with SiC addition exhibited high undercooling as Δ T max= ( ΔT/Tm) = 0.28 and formed the amorphous phase. Furthermore, in Nd-(Fe, Co)-Al alloys, bulk amorphous and metastable phase with high coercive force were formed by addition of Co. The microstructure of Nd-Fe-Al systems significantly changed to cell structure from lamellar structure on the cooling rate of 100 K/s. High coercive force appearance of metastable phase in Nd-Fe alloys was clarified to depend on the random magnetic anisotropy between Nd and Fe valence electron. These results were clarified the effects of the new gas jet flow type electromagnetic levitation process to produce the new materials.

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Containerless processing, which can control the undercooling level of the droplet, is now widely used to form the metastable phase from the highly undercooled melt. However, the metastable phase obtained often remelts due to the latent heat ejected from the stable phase when the stable phase nucleates on the metastable phase. On the other hand, splat quenching, which can reduce the reheat of the system because the latent heat is extracted into the substrate, had been limited to the quenching of the superheated melt. The combination of levitation furnace and splat quenching provides the effective cooling because the undercooled melt can be quenched. In this review, we focus on the direct growth of the peritectic phase from the undercooled melt by this combination.

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Electrostatic Levitation Furnace is an effective method for rnetastable phase research. This report describes the development status of the Electrostatic Levitation Furnace (ELF) for microgravity experiments. The technical study model of ELF has been fabricated. Some ground based and parabolic flight experiments using the technical study model have been carried out to evaluate the performance. As a current result, we have succeeded in stable levitation of metal and non-metal samples. In the parabolic flight experiments, levitation melting of Zr sample and solidification from the supercooling liquid state were completed during reduced gravity condition. Future plans of experiments using technical study model and system configuration image of the ELF for ISS Japanese experiment module ``Kibo'' are introduced.

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The study of thermophysical properties of metallic and semiconductor melt is important to understand heat and mass transport phenomena and their structures. The properties are obviously sensitive to contamination of the melt by impurities. Therefore containeiiess experiments in microgravity environment are expected. In this study, convection in the levitated melt is suppressed by combining with a magnetic field and EML. Density of molten pure silicon has been measured over wide temperature ranges including the undercooled region. Based on these new improvements, the result for the density of molten silicon can be expressed by ρ (T) =2.514-2.659 X 10-4(T-Tm)gcm-3 (1370 K＜ T＜1770 K).

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The ISS (International Space Station) Education Programs in JAXA (Japan Aerospace Exploration Agency) aim to arouse students' interest in the space environment utilization on the ISS and enhance their knowledge of science and technology. JAXA has offered Parabolic Flight Education Program for university students to make microgravity experiments.

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When magnetism is put on ferrofluid, spike-like figure appears. This is called the ``Spiking Phenomenon''. The``Spiking Phenomenon'' on the ground receives the influences from the surface tension, the magnetic energy, and most of all, the gravity from the earth. The purpose of this experiment is to observe the behavior of ferrofluid different from the ground by putting magnetism on ferrofluid under microgravity, and to examine the influence that the surface tension and the magnetic energy is exerting on ferrofluid.In this experiment, we observed many difference in the behavior of ferrofluid. The spike of ferrofluid expands longer under microgravity compared with the ground, and each spike has worn roundness. This is because the influence of gravity got small and the influence of the surface tension appeared greatly. Moreover, various shape was formed in the process of combining strength of an upper and lower electromagnet.

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Previous studies from our laboratory demonstrated that the vestibular system has a significant role in controlling arterial pressure during gravitational stress in conscious rats. However, the role of vestibular system in humans is still unclear. Accordingly, the role ofvestibular system in controlling arterial pressure during gravitational stress was examined in humans. To disturb the normal vestibular function, GVS (galvanic vestibular stimulation) was applied. In GVS, electrical stimulation was applied through the electrodes attached on the mastoids. This artificial stimulation would mask the optimum input to the vestibular system, thus could not accept the normal input induced by position or gravitational change. With measuring the arterial pressure, microgravity for 20 seconds was applied by parabolic flights. The arterial pressure response was compared between GVS (on) and GVS (off). In GVS (off) , arterial pressure was increased at the onset of microgravity, and then decreased below the pre-microgravity control level. The initial increase in arterial pressure was completely abolished in the subjects with GVS (on). These results indicate that the vestibular system operates for controlling arterial pressure upon the gravitational change in humans.

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``Sound Wave Sculpture'' is sculpture that is formed by music composed with sinusoidal sound waves which create the movement of particles in a cylindrical container. In the basic experiment, we put spherical styrene foam (2 mm diameter) into a cylinder. The purpose of the experiment present here is to change the contents and investigate the difference in the dynamics seen. In addition to visual data, the difference of behavior is measured as a function of output voltage of the power amplifier. As the result, interesting movements are shown as a form of artistic expression. The results show various behaviors. For spherical styrene foam 2 mm and 5 mm diameters the bigger spheres arranged themselves vertically while the smaller ones dispersed in a random pattern with the sinusoidal waves. Whilst spherical brass balls (2 mm diameters) go straight ahead from center of the speaker in a direction parallel to the cylinder, and move across the cylinder at a right angle to it with an interesting layer formed by the sinusoidal waves. Brass balls show a beautiful bouncing motion. Feathers show bigger movement due to the air resistance. Silver beads showed beautiful reflective lights from blinking LEDs. A final observation is that, in micro-gravity environment, the visualisation of sound wave's is possible even by weak sinusoidal waves, and the weak sinusoidal waves look much more beautiful than strong sinusoidal waves when we use spherical styrene foam.

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In the near future, on the assumption that human beings will live in space, it is necessary for us to develop new technologies which make living in space much more comfortable, convenient, and enjoyable. The crews who have some different cultures work together for a long duration in the closed environment in space, so daily clothing has a very powerful effect both physically and mentally for our well being. As clothing has never developed for microgravity in the spacecraft, it could be very useful to develop such daily clothing to life in space for astronauts and space tourists. In this study, we tried to observe a change of form of clothing materials. In addition, it was measured continually air temperature and humidity inside of clothing environment, skin temperature and heart rate in changing gravity conditions utilizing parabolic flight in the airplane. As a result, it is shown that the materials movement for clothes is related to physical properties of materials. And then, changing the shapes of clothes has an effect on the distribution of humidity inside of clothing environment.

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We have performed combustion experiments ofJapanese sparkler called ``senkoh-hanabi'' in 20 sec microgravity conditions by parabolic flight of airplane. TheJapanese sparkler in a closed chamber was ignited by hot wire and the occurrence of spark was observed by video camera. Under the microgravity condition, Japanese sparkler was not sparking.　However, after the change of gravity from 0 G to 1.5 G, Japanese sparkler suddenly began to spark. From the observation we conclude that the convections of air around the fire-ball of Japanese sparkler are important to generate sparks.

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The formation mechanism of coronet was investigated using a microgravity obtained during parabolic flight of a jet plane Gulf Stream II. When coronet height was plotted against the Weber number, gravitational acceleration appears to affect the height of coronets. The Froude number cannot be an appropriate parameter to describe crown height.

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