Okara is apt to go bad quickly, but it is rich in many nutrients for feedstuff. Total bacterial counts of raw okara increased rapidly. We inoculated three lactic bacteria or bacteria isolated from okara to raw okara and incubated in aerobically or anaerobically conditions. All inoculated bacterial counts increased, however total bacterial counts also increased in all incubations. In anaerobic incubation of okara, lactic acid bacterial counts increased, and pH lowered. Rats were fed control diet or 20% of lactic fermented okara containing feed for 14 days. Body weight gain and feed intake were not influenced, and fecal weight and fecal nitrogen output increased significantly by okara intake. This result suggested that lactic fermented okara was available for use as feedstuff. A large effect was not expected by inoculation of lactic bacteria by way of prevention of putrefaction.

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Typical boron compounds are sodium tetraborate decahydrate (borax) and orthoboric acid (boric acid). These boron compounds are broadly used as medical supplies, fireproof material, the raw material of special glass, photographic developing agent, etc. It is well known that boric acid is obtained by acidification of borax, however, it is unclear whether the reverse reaction from boric acid to borax takes place or not. In this experimental study, sodium hydroxide was added to boric acid solution to make basic, and the formation or crystallization of borax from boric acid solution was examined, especially from pH point of view.
The experimental results showed that borax crystals were formed from the solution of boric acid by adjustment of pH to 8-11 and by addition of seed crystals of borax. The maximum formation amount of borax and the maximum formation rate were observed when the pH of boric acid solution was adjusted to 9.85. The adjustment of pH to 4-7 yielded boric acid, while in the pH range of 7-8 and higher than 11 there appeared no precipitates without evaporating the water from boric acid solution. pH adjustment is important to crystallize boric acid and borax. And it was recognized that borax was obtained by basification of boric acid solution.

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By structure activity relational investigation in terms of toxicity of 221 kinds of chemicals, it is suggested that heavy metals were highly toxic for human cells and Daphnia magna and phosphorous chemicals were highly toxic for Daphnia magna. There were no correlations between the toxicity parameters of 221 kinds of chemicals to HepG2 (human hepatoblastoma cells) and Daphnia magna. The parameter indicating toxicity strength to Daphnia magna was higher than that to human cells. The parameters indicating toxicity quality to Daphnia magna were very smaller than that to human cells.

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Phosphor materials have been searched in the Sr-Al-B-O system. For a molar ratio (Sr_1-xEu_x) : Al : B = 1 : 2 : 2 (x = 0.01), a crystalline layered compound SrAl₂B₂O₇：Eu²⁺ was synthesized at 900 °C for 12 h in a reductive atmosphere. The SrAl₂B₂O₇:Eu²⁺ showed blue emission under UV (254 nm) and VUV (Vacuum Ultraviolet, 146 nm) excitation. For the ratio (Sr_1-xEu_x) : Al : B = 2 : 2 : 2 (x = 0.01), a transparent glass and SrAl₂O₄ component with a long afterglow phosphorescence was found.

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Vacuum ultraviolet (VUV) phosphors are inorganic optical materials used in mercury-free fluorescent lamps and plasma display panels (PDP). Promising red VUV phosphor, GdBO₃:Eu³⁺, were synthesized by a flux method. Studies of the phosphor synthesis reaction show that the flux (e.g., B₂O₃, RbCl) serves as an important reactant. The phosphor particles prepared by the flux method at 1100°C with RbCl flux had the highest PL intensity under VUV excitation (146 nm), which corresponded to 126 % of that of particles prepared from raw material mixture without flux.

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The deposition velocities of sulfur dioxide and sulfate aerosols were measured by using a substitute surface technique. Acidic and neutral sand were used as substitute surfaces to distinguish the deposition of sulfur dioxide from that of sulfate aerosols with an expectation that the acidic sand should prevent SO₂ gas from depositing on the substitute surface. The deposition velocity of sulfur dioxide was estimated as 0.77cm/sec which was well agreed with the previous studies, while 2.1cm/sec, which was estimated as a deposition velocity of falcate particles, was higher than those from previous studies.

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