Evaluation of long-term sulfate resistance was carried out using various fly ash blended cements. Specimens after extended immersion in sodium sulfate solution were examined to determine expansion as well as hydration products by XRD and sulfur distribution by EPMA. It was found that higher fly ash replacement ratios affected strength development in early age but also retarded penetration of sulfate ions. Addition of limestone powder or increase in SO₃ content resulted in a reduced quantity of internal monosulfate, thereby limiting the formation of expansive ettringite with external sulfate ions. Excessive addition of SO₃ was found to cause internal expansion due to the reaction with Al₂O₃ in the glass phase of fly ash. However, addition of limestone powder and appropriate increase in the amount of SO₃ provided fly ash blended cement with excellent sulfate resistance after 6 years of exposure, without causing internal expansion or significant strength loss.

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 This study examined the strength and fracture mechanics properties of ultra high strength fiber reinforced concrete with shrinkage reducing agent. Furthermore, the effects of the addition of shrinkage reducing agent on the crack initiation load and crack width in RC members using the ultra high strength fiber reinforced concrete were investigated by double-pulling test. The specimens with cracks which were caused by double pulling during the loading test were immersed in synthetic seawater for 12 months to observe corrosion of internal steel bars. The results showed that the addition of shrinkage reducing agent caused increases in fracture energy and initial crack strength, thereby inhibiting increase in crack width in the RC members using the ultra high strength fiber reinforced concrete. It was also found that no corrosion occurred in the internal steel bars after 12 months of immersion.

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 This study experimentally investigated mechanical properties of extremely dry concrete made with Ecocement and evaluated its applicability to roller compacted concrete pavement (RCCP) by field construction test. The mechanical performance of extremely dry concrete with Ecocement was found to be almost equal to or better than that with ordinary portland cement. The field test with Ecocement showed that it was possible to manufacture and ship concrete with required performance in a stable state without problems. Furthermore, it was found that by properly selecting mix proportions of the concrete, good workability and required mechanical properties could be achieved. The above results demonstrated that Ecocement was satisfactorily applicable to RCCP at a practical level.

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 EM Funen Dannetsuzai is a noncombustible heat insulating spray material which is applied in two layers. The base layer has a heat insulation effect, and the finish layer provides surface protection with an aesthetic effect. This study investigated the physical quality properties of the material including incombustibility and thermal insulation performance and compared these properties with those of spray rock wool or other inorganic heat insulating materials. The results showed that EM Funen Dannetsuzai satisfied the certification requirements for noncombustible materials and had a stable thermal conductivity of 0.045W/(m·K) or below. It was also found that EM Funen Dannetsuzai had the same or better performance to spray rock wool or other inorganic heat insulating materials.

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 Phosphorus is an essential nutrient for all living organisms and one of the three important fertilizer elements indispensable for food production. However, the natural reserves of rock phosphate which is the source of phosphorus are extremely limited and being exhausted very rapidly. Global interest in phosphorus recycling is increasingly high as the resource-rich countries move toward limiting the exports.
　Rintoru^Ⓡ is an amorphous calcium silicate hydrate (A-CSH) that we developed for phosphorus recovery from waste water and recycling of the recovered material as a fertilizer. In this paper, we carried out demonstration tests of phosphorus recovery from excess sludge filtrate from a sewage treatment plant at the Hakodate Bay Purification Center in Japan. The results showed that the A-CSH could recover phosphorus on a stable basis regardless of seasons, and that phosphorus recovered A-CSH met the requirements for Byproduct Phosphate Fertilizer specified in the Fertilizer Regulation Act.

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 Home and public aquariums have been attracting increasing attention as a facility that provides a relaxing and comforting environment to the people living in highly developed modern societies. An aquarium is a closed water environment to keep fish, and it is absolutely essential for the keepers to maintain water quality properly using water purification systems. One of the important purification devices is the filter that captures bacteria. Power House^Ⓡ is our high-performance filter medium product for water purification used for keeping aquarium fish and shrimp which are known to be extremely sensitive to water quality change or worsening. This report describes the mechanism of water purification required of aquariums and explains technical advantage of Power House.

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