To avoid a food crisis caused by the population explosion, preservation of resources and the environment as well as an increase in biological production in shallow seas are essential in Japan, which is surrounded by water. However, since resources and the environment have been harmed by the ocean dumping of fly ash (FA) and clinker ash (CL), gravel extraction for aggregate and industrial by-product, we developed waste use-concrete-blocks containing these wastes for seaweed-beds. Then we investigated the preservation of resources and the environment and the increase of biological production in shallow seas using these beds to solve these problems.
In previous papers, strength test, elution test, and aquatic life's ability to grow were investigated using several types of concrete-test-pieces (thin layer test piece and medium-sized rectangular prism) containing various ratios of cement, FA, CL, Fe, including molding sand and zeolite, and the basic results were reported. Based on the results, three types of large test blocks containing different materials were prepared for this investigation. The test blocks were sunk in the test sea area and the temporal variation of the amount of seaweed on the blocks was measured.
In this paper, their availability as substrate for the seaweed bed is demonstrated.
Three types of concrete-blocks were prepared: plain (normal concrete), FA & CL (concrete containing FA and CL as aggregate) and FA & CL+zeolite+Fe including molding sand (concrete contained FA, CL, zeolite and Fe including molding sand). Five blocks of each type formed each unit, and then, they were sunk in the test sea area at a depth of 5 m in two layers. After that, four diving surveys were conducted over a period of one year and nine months. In this investigation, the Quadrate Method was employed to measure the amount of seaweed and the Line Transect Method was used to observe the swarm characteristics. In the second and fourth months, the initial amount of seaweed on each type of block was measured.
In the results, the amount of seaweed on FA & CL+zeolite+Fe including molding sand was equal to or greater than that on the other two types of blocks. This means that aquatic life was able to suitably adhere and grow on the blocks containing FA & CL+zeolite+Fe including molding sand. Furthermore, the amount of seaweed on the seaweed-bed was greater than that on the adjacent seaweed-beds made of natural stones. As a result, the blocks made of FA & CL+zeolite+Fe including molding sand accelerate the formation of seaweed-beds, and therefore provide a good substrate for seaweed-beds.

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The dual sorption and diffusion theory presented for the interpretation of the diffusion behaviors of acid dyes in nylon, has been applied to the interpretation of the diffusion behavior of sodium chloride in Japanese radish under cooking condition.A simple and convenient method, FRITRUC, to obtain one dimensionald iffusion profile in the radish substrate was proposed. Fick's diffusion coefficient obtained from the profile showed a maximum, indicating the characteristic feature of the dual mechanism. The thermodynamic diffusion coefficient of sodium chloridep artitionedi n the radish from the solution, was found to be 2.1×10^-5cm²s^-1, ca. 1/3 of that in boiling water. Discussions in some details were extended for the possible applications of the present method to the seasoning mechanisms in cooking area.

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1-Phenyl-3-methyl-4-stearoyl-5-pyrazolone (HC₁₈) loaded on a silica gel (SG) was prepared in our laboratory, and used to determine the diffusion reflectance/spectrophometric of iron (III) ion. Iron (III) ion was quantitatively retained on the absorbent, HC₁₈/SG, from an aqueous solution of pH>2.0 in the batch experiment. The calibration curve for iron was linear over 0.5-10μg. The relative standard deviation (n=7) was less than 3 %. The detection limit (1% absorption) was 0.1μg. The absorbance of the Fe (III)-HC₁₈/SG, which turned red was stable for at least one month, and no change in the absorbance was confirmed. The recovery from 1000 ml of sample solution containing 8μg of iron was about 100%. In the column experiment, iron (III) was quantitatively retained with 0.5μg of HC₁₈/SG when the flow rate of the sample solution was lower than 8 ml/min. Alkali and alkaline earth metal ions, and other metal ions such as cobalt (II) or nickel (II), had no effect on the determination of iron (III). The method was applied to the determination of iron (III) in a salt sample and environmental samples such as a sea water. The recovery of iron (III) added to these samples was approximately 100%.

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A two-dimensional water jet of 2.8mm × 280mm is discharged horizontally near thesurface of a quiescent water vessel of 1m in width, 1m in depth and 4m in length. The vertical distribution of the velocity is measured at distances of 0.5m, 1.0m and 1.5m from the discharge port. The measured valuesare compared to Reichardt theoretical result of a two-dimensional turbulent free jet and the numerical results of relevant Navier-Stokes equation with respect to the pattern of the velocity distribution, maximum velocity and half width of the jet plume. It is concluded that the principal characteristics of the present measured results agree with Reichardt's theoretical result. However, the virtual kinematic viscosity seems to be about 1/4to 1/8 of that of the air jet proposed by Reichardt.

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Carotenoids in freeze-dried samples of Thraustochytrium CHN-1 were extracted bymeans of supercritical CO₂ fluid extraction (SFE) at a temperature of 40°C and pressures of 20 Mpa. Thisstudy was carried out on crushed Thraustochytrium CHN-1. The extraction yields of carotenoids and fatty acids were lower than those of liquid extractions (CHCl₃: MeOH=2:1).

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