A NH₃-PSA process was successfully developed for selective separation of NH₃ from a NH₃ (5%) -H₂ (45%) -N₂ (50%) mixture which would be produced from a novel nitrogen fixation process catalyzed with Ruthenium over 200-250°C at atmospheric pressure. The PSA process with dual columns (33mlx2) was designed to be operable with mild conditions of the maximum adsorption pressure of 880-1000 Torr and the minimum desorption/vacuuming pressure of 20-60 Torr, processing the feed mixture at rate below 10l/h. A commercial 3A (K, Na) type zeolite demonstrated distinguished performances: unreacted H₂+N₂ mixture was recovered with containing only 0.2% of NH₃, and the NH₃ of 5% in the feed was condensed up to 64% without any change in ratio of remaining H₂ to N₂.
The key of the PSA process was the selection of adsorbent which could adsorb NH₃ component predominantly in uptake or speed. The adsorbents tested in this study were as follows; the two kinds of commercial zeolites and three kinds of carbonaceous porous carbons such as a supersurface activated carbon, a molecular sieving carbon (MSC) for air separation PSA, and a wood based porous carbon prepared by heat treatment of a compressed saw dust at 1000°C. The selective NH₃ adsorption character found in the PSA performance and the porous structure and pore shape were discussed for improvement of more favorable adsorbent specified for this NH₃-PSA process.

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A centrifugal phytotron was designed and fabricated to study the effects of gravity on the growth of plant. The magnitude of centrifugal force can be selected arbitrarily up to 4G by controlling angular velocity of cultivation drum (1 m diameter). Environmental factors in this phytotron such as temperature, humidity, CO₂ concentration and light intensity can also be conditioned.
On the earth, different magnitude and different direction of artificial gravity, which is centrifugal force plus 1G earth gravity, distribute over the cultivation drum. Results of spectral analysis on vibration of the cultivation drum showed that overall vibration changed with centrifugal force and ranged from 0.7 to 2.1G.
Wind velocity over the cultivation drum increased with raising centrifugal force and ranged from 1.5 to 2.7 m s^-1.
Results of preliminary cultivation experiment with radish (Raphanus sativus L.) showed that mean dry weight of the plants cultivated under centrifugal force of 2G was not significantly different from that of the plants cultivated under centrifugal force of 1G, and root/total dry weight ratio increased with raising centrifugal force. These tendency, however, might be due to several physical factors described above.
Isolation of gravitational effect on the plant growth from existing influential factors such as the vibration and wind will be required for further experiment.

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The constructed closed recycling system discussed in this report will be economically viable in future for the production of fish and vegetable in earth, space station and space colony, further, it will contribute a lot in prevention of pollution in the world's ecological system.
Using the equations, the expected nutrient characteristics of waste water were determined and it was found that the resulting nutrient balance was almost same as that in hydroculture solution when KOH was added to maintain pH level. However the resulting concentration of nutrient was quite low for plant production. This problem was solved by using reverse osmosis (RO) system whereby the low concentration of waste water was made higher by separation. The advantage of RO system are low energy cost, simple equipment, no effect composition of water components. After testing five separation membranes, the permeated water rate of SU-710 was larger than SC-3100, hence it was found that SU-710 membrane was the best for this waste water. By using reverse osmosis four levels of concentration were produced from fish waste water and used plant growing experiment, it was found that plant grow well at a level about above EC1.6 sector. This plant consumption of ions were measured during the growth period.
RO system could combine fish and plant production through the advantageous use of separated high concentration water for plant and permeated water for fish in the integrated combined system.

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Microorganisms are beleaved to play essential roles in keeping terrestrial environment. This may be true in CELSS. However, the true properties of microorganisms in natural environments are not well understood due to the lack of suitable detection systems. A noble method for the exploration of terrestrial and extraterrestrial soil microorganisms, especially targeted for Mars, Space Station and CELSS, has been developed.
The method is based on the microscopic observation using fluorescence techniques. Microorganisms could be fluorescent by adsorption, enzymatic cleavage of extrinsic fluorescence chromophores and also by intrinsic chromophores. Since this technique requires no incubation, native microscopic ecology can also be observed. This technique is proved to be sufficient enough to detect almost all terrestrial microorganisms in natural environments and to classify the microorganisms depending on their physiological properties.

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