The present paper describes the multi-purpose utilization of ocean thermal energy offshore of Tsushima Island.
The practical application of ocean thermal energy conversion (OTEC) and desalination plants is expected due to shartages of electric power, drinking water, new industry and development of fisheries resources on Tsushima Island. We conducted oceanographic observations in the area northwest of Tsushima Island in August, October and November 2005; July, August, October and November 2006; August, September, October and November 2007, and November 2008 to obtain physical and chemical data (water temperature, salinity, dissolved oxygen, nutrients and velocity of currents) and topographic data, which is necessary for designing an Integrated Hybrid OTEC System (I-H OTEC system).
A conventional design for the I-H OTEC system is being conducted with these data.
In this paper, numerical results are reported for a 1,000kW I-H OTEC system with plate-type heat exchangers and ammonia as a working fluid and described for effect of the variation in salinity of sea water for an I-H OTEC system.
The objective function obtained is 9.87m²/kW when the warm sea water inlet temperate is 28.7°C and cold sea water inlet temperate is 4.1°C.
The ratio of objective function γ′_min to γ_min (35‰) is 0.97 when γ′_min is valve in the case of 30‰ salinity of surface sea water and 35‰ salinity of deep sea water and γ_min is the valve in the case of 35‰ salinity of surface and deep sea water.
The ratio of objective function γ′_min to γ_mi (35‰) becomes smaller when the salinity of surface sea water is higher than the salinity of deep sea water.

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Micro-facet formation processes were observed with atomic force microscopy (AFM) at low index crystal faces of NaCl in ethanol solutions with and without additives. The most stable face in each solution was determined by observing atom-resolved AFM images. In ethanol, (113) surface was the most stable. Adsorption of O atoms of ethanol molecules at {111} ledges formed by Na ions was proposed. In an ethanol solution of CdCl₂, (112) surface was stabilized. Most probably chain structure of CdCl₆ complexes were formed along the {111} ledges formed by Cl ions. In an ethanol solution of HgCl₂, (110) surface became atom-flat. The (100) surface and monatomic {111} ledges on it were also stabilized in the same solution. Formation of HgCl₆ complexes was proposed to explain the stabilities of the surface structures. Friction coefficients were measured with frictional force microscopy (FFM) for atom-flat (100), (110) and (111) faces. Frictional anisotropy was clearly observed at the (100) and (110) faces at relative humidity lower than 60%. Anisotropy was not observed for the (111) face probably due to strong adsorption of water molecules at the electrically polar surface even at 15% humidity.

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Industrial crystallization should be carried out under high suspension conditions in order to obtain salt products efficiently. However, under such conditions, the nucleation rate becomes high. Therefore, it is necessary to make a model of fine crystal generation and to control the excess number of fine crystals. This study focused on the characteristics of fine crystals generated under high suspension conditions and on the dissolution phenomena by modulated (undersaturation) operation. Undersaturation condition was carried out by injecting of dissolution water. As results, the following conclusions were obtained. (1) The fine crystals could be classified into two types according to the shape of the fine crystals. The effects of the injection of dissolution water were different depending on the shape of the fine crystals. (2) The dissolution water was effective for the preferential dissolution of the fine crystals and modification of the crystal surfaces directly related to the fine crystal generation. (3) Control strategies with local under saturation were proposed in order to control fine crystal generation.

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Disease outbreaks will likely occur frequently with intensive cage cultures. Hence protective strategies are needed, and an effective approach is to enhance the piscine immune system. In this experiment, the effects of oral administered Plant Mineral Mixture, a mineral mixture derived from wild plants, on the prevention and the extermination of skin fluck disease of amberjack, which is caused by the parasite Benedenia seriolae, and on the non-specific biodefense activity of amberjack Seriola dumeruili were examined. Fish were divided into 2 groups : the control was fed a commercial diet and the mineral group was fed the same commercial diet containing 0.05 to 0.06% Mineral Mixture at 6 to 7% of fish body weight every two or three days, respectively. The dose of Mineral Mixture was about 45mg/kg body weight/day every two or three days. Fish were cultured for 13 weeks. The number of B. seriolae on the fish skin decreased significantly in the mineral group. A significant increase in non-specific biodefense activities such as the number of skin mucous cells (that is, skin mucous secretion volume), lyso-enzyme activity and lectine activity in skin mucus, the number of phagocytes and lymphocytes, the phagocytic activity and NBT reduction ability of granulocyte, the activity of natural killer (NK) like cell, the alternative pathway of complement activity (ACH₅₀) and lyso-enzyme activity in plasma were also found in the fish with oral administered Plant Mineral Mixture. These results suggest that the oral administration of Plant Mineral Mixture enhanced the non-specific biodefence activity, and was effective for preventing and exterminating skin fluck disease in amberjack.

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The effect of the transcription of proline transporter genes on the mechanism of quick adaptation of Escherichia coli cells under high salinity was analyzed. E. coli has three independent proline transporters, namely PutP, ProP and ProU. By using moderate salinity stress method, we made three different types of E. coli cells which transcript proline transporter genes: (i) PutP gene; (ii) PutP and ProP genes; (iii) PutP, ProP and ProU genes. Although the growth of type (i) E. coli cell was inhibited at 1.2M NaCl culture condition, type (ii) and (iii) cells showed the recovery of growth. The uptake of proline by E. coli as compatible solute was in good accordance with those of cell growth. These data showed that the transcription of proline transporter ProP played an important role in E. coli cells adapted with 1.2M NaCl culture conditions rapidly.

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For the actual use of a technique to accelerate apparent crystal growth rate by the adhesion of fine crystals that are suspended in the mother liquid on seed crystal surfaces, effects of origin of suspended fine crystals and surface roughness of seed crystal on the apparent crystal growth rate was examined. Under conditions of supersaturation ΔT=1–30 [K] with the amount of suspended fine crystals N_fine=2×10⁴–7×10⁵ [kg-solution^–1], batch crystallization tests for growing one seed crystals of sodium chloride using cooling fluidized bed type crystallizer were attempted experimentally. In the experimental, the apparent crystal growth rate increased with the supersaturation [mol/kg-H₂O] and amount of fine crystals N_fine [kg-solution^–1] unrelated to the origin of fine crystals and the surface roughness of the seed crystal. Apparent crystal growth rate (dl/dt)_AV [m/h] is showed as a equation; (dl/dt)_AV= (1.07×10^–2+2.90×10^–8 N_fine) ΔC. By observation of the cross section of crystals grown under the high crystal growth rate of 4,780 [μm/h], it was thought that the quality of grown crystal was similar to common industrial crystals of sodium chloride. From these results, it was considered that the high apparent growth rate was obtained by increasing the fine crystals with an increase in the supersaturation

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