An experimental study of hydrous mineral formation reaction between the synthetic forsterite and water vapor has been carried out with autoclaves at temperatures and pressures below the critical point. We succeeded in synthesizing hydrous minerals under these conditions for the first time. Patterns obtained by powder X-ray diffraction and with using a Gandolfi camera show that serpentine (chrysotile or lizardite), brucite and brucite-like material were formed by the hydration of forsterite. The reaction nearly obeys 2Fo+3H₂O(g)=1Serp+1Bru. The IR absorption spectra of the charge using Fourier transform infrared microspectrometer confirms the formation of hydrous phase since an absorption peak appeared at -3690cm^-1, which can be assigned to an absorption peak of the OH-bond. The rim thickness of the layer produced by the hydration of forsterite was estimated to be roughly 1μm after >1000hr, at 230 °C and a water vapor pressure of 27bar. The hydration rate is much smaller than that predicted theory.

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This paper deals with the dynamic response of a central core type embankment dam under level-II earthquake excitation, which is much severer than that in the conventional earthquake resistant design before Hyogoken-Nanbu earthquake. The aim of the paper is to estimate the magnitude of seismic force exerted by the level-II motion and evaluate the dynamic effect in terms of the seismic coefficient, because it plays the most important role on the earthquake resistant design. Assuming elasto-plastic behavior of dam materials, the two-dimensional finite element model was used and also generation of level-II motion was carried out. Judging from several results of the simulation, the maximum value of the seismic coefficient reached about 0.7, whereas the usual design value for embankment dam is less than 0.15. This value emphasizes the severity of the level-II earthquake.

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Metabolic pathways for synthesizing amino acids in 7 archaebacteria were compared on the basis of enzymes identified using their genomic DNA sequences. No essential difference was found between the set of enzymes identified for .a heterotroph, Archeaoglobus fulgidus, and for those of two autotrophs, Methanococcus jannashii and Methanobacterium thermoautotrophicum. It is likely that these three organisms are able to synthesize all the 20 types of amino acids found in proteins in essentially the same way. From the genomes of the other four heterotrophs, Pyrococcus abyssi, Pyrococcus sp. OT3, Thermoplasma volcanium, and Aeropyrum pernix, most of the genes coding for enzymes in the pathway for synthesizing histidine from 5-phosphoribosyl-1-pyrophosphate were missing, as were many other genes coding for enzymes in the pathways for synthesizing valine and leucine from pyruvate. The pathways for synthesizing aromatic residues from 3-phosphoglycerate seemed to be missing from P. OT3, while in T. volcanium the pathways starting from oxaloacetate were found to be significantly incomplete.

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The population explosion in the 21st century will have a severe impact on the problems associated with food supply and the environment. Even at present, the shortage of food protein resources is an acute problem. Effective countermeasures to cope with the ever worsening shortage of protein resources in the next century are absolutely essential. We have developed methods to produce and isolate single cell proteins in an ample yield. We have also found that among food grains rice has the highest protein content, and have found that the protein in the grain is present in discrete particles, for which we coined the name“protein bodies”. Rice protein has a relatively good balance of essential amino acids, and hence a relatively high nutritional value. We were able to increase the nutritional value further by fortifying it with L-lysine by a novel soaking method. New methods of food preservation will be important to cope with the 21st century food problems, because a large amount of food is lost either on the farm or during storage, to microorganisms, rodents and insects. We developed the carbon dioxide exchange method (CEM), in which food is stored under CO₂ in hermetically sealed containers (called Hibernation Rice). CO₂ is reversibly adsorbed to, and desorbed from the amino groups of food proteins. We also developed underwater and underground food storage methods earlier (1967-72), to take advantage of constant low temperatures in these conditions. Based on these studies, large scale storage methods in 200kg steel drums in CO₂ have been developed On an industrial scale which is operated on a commercial base. Methylbromide destroys the ozone layer, and will be banned completely from use for food preservation or any other purposes. Storage under CO₂ is far superior to methylbromide because CO₂ completely eliminates the rice weevil and otherinsects, has no toxicity or public health problems, and is economical. CO₂ is a very effective synergist when used with the pasteurization gas, ozone, to sterilize foods against the virulent pathogenic strain of E. coli, O-157 and black pepper which are known to be contaminated with bacteria. The use of CO₂ may add to an already high production of CO₂ from other sources, such as combustion of fossil fuels. Effective measures to prevent leakage of CO₂, are needed. We are striving for an innovative idea to prevent the escape of CO₂ and the consequential warming of the earth.

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