本研究では、の廃材粉末を固化し、特有の緑色と吸着特性を活かした機能性建材として再利用することを考えた。Ca/Si比を0.4にしたと消石灰の混合試料の成型体に対し、180℃、10hの飽和水蒸気圧下で水熱処理を施した結果、曲げ強度が12MPaの緑色の固化体の作製に成功した。に含まれる石英と消石灰の反応により、成型体の原料粒子間の空隙にトバモライトが析出し、これにより固化体の強度が発現した。XRD分析結果より、の構成鉱物である緑泥石は反応に殆ど寄与しなかった。また、アンモニアガスの吸着試験を行った結果、固化体は粉末そのものに比べ高い吸着性能を示した。

抄録全体を表示

Hinai green tuff is quarried in Odate-shi, Akita prefecture in Japan and used for architectural materials. Hinai green tuff suspension is generated from the cutting and the grinding process and it is necessary to treat the solution with precipitants. A chemical flocculant has been used as a precipitation agent for fine particles in the suspension. However, using a chemical flocculant agent produces a wasteful mixture of particles and flocculants, which are impossible to be used as a resource. Therefore, it is necessary to develop a new precipitation method without using precipitants for green tuff particles. In this study, the zeta potential of Hinai green tuff particles in suspension was measured to gain the basic electrochemical properties of the colloidal suspension. We then developed a new precipitation method using sonochemical reaction at 200 kHz, 200 W. From results of the zeta potential measurement using an electrophoresis method, the particles exhibited −50 mV at pH 7.0 and 0 mV at below pH 4.0. Sonochemical reaction was applied to control the pH of the suspension to precipitate the Hinai green tuff particulate. When ultrasonic irradiation was applied to the Hinai green tuff suspension, the pH decreased to 4.0 in 80 min and finally reached 3.3 in 180 min. We successfully extracted pure Hinai green tuff particles as precipitates from the suspension using ultrasonic irradiation.

抄録全体を表示

 本研究では，産業廃棄物である砕石ケーキの抗菌剤としての有効利用を指向し，アルカリ反応を用いて緑色凝灰岩砕石ケーキから銀イオン担持能をもつゼオライト系物質の調製を試みた。緑色凝灰岩砕石ケーキは石英，長石，白雲母，緑泥石などのケイ酸塩，アルミノケイ酸塩から構成され，ケイ素とアルミニウムを主成分としていた。砕石ケーキを 0-4 M NaOH 溶液中にて 80, 120, 160℃で 24 時間加熱した結果，原料中の石英が溶解する条件で方沸石を含むゼオライト系物質が生成した。方沸石を含む生成物は高い銀イオン吸着能を示した。

抄録全体を表示

秋田県大館市比内町で産出する緑色凝灰岩は建築石材として用いられ,吸湿性や防カビ性などの機能性を有することが定性的に知られている。筆者らは,これらの性質を生かしつつ,より施工性に優れた緑色凝灰岩の粉砕石粒を用いた壁材を開発した。本研究では,その調湿性,化学物質吸着性ならびにカビ抑制作用を検討し,いずれも一般的な塗り壁材である川砂よりも優れていることを明らかにした。とくに,化学物質吸着性については,高機能塗り壁材である珪藻土よりも持続性において優れていることが示唆され,緑色凝灰岩の粉砕石粒が環境性に優れた塗り壁材として利用可能であることが示された。

抄録全体を表示

The green tuff from Hinai town, Akita is popular for architectural materials because of its beautiful pale green color and thermal and moisture retaining properties. When this stone is quarried and grinded for making products, approximately 60% of all quarried stone becomes the waste stone and it is required to be utilized effectively. Hinai-Green tuff is a porous media and it has abilities to neutralize acids and elute some minerals. These abilities may be effective for growth of microbes and our research group carries out the development of effective utilizations of Hinai-Green tuff as microbial activator. In this paper, the effects of Hinai-Green tuff on pH adjustment and microbial activities are described.
Hinai-Green tuff had an ability to neutralize both acid and alkaline water and especially neutralized acids effectivelly. For example, acid water of initial pH3 was neutralized to pH7 by adding 10(w/v)% Hinai-Green tuff into the acid water. Therefore, Hinai-Green tuff can neutralize acid soil and water and adjust acid environments to adaptable environments for microbes. Moreover, Hinai-Green tuff could buffer decrease in pH. The pH of water containing Hinai-Green tuff did not decrease rapidly with adding drops of 0.1M HCl, and especially the buffer action was strongly observed at pH 7 to 8. Hinai-Green tuff is very helpful to maintain pH appropriate for microbes for long time against decrease in pH caused by acid rain and/or acid metabolites of microbes. And pH adjustment effects of Hinai-Green tuff were caused by the ion exchange between Ca²⁺ leached from the stone and H⁺.
Consequently, microbes grew actively in a medium containing Hinai-Green tuff because of its pH adjustment effects. However, microbes did not grow in a medium containing natural zeolite from Futatsui town, Akita. The effects of Futatsui-Zeolite on pH adjustment for acid were low compared with Hinai-Green tuff.

抄録全体を表示

A borehole meter with a built-in laser displacement sensor has been developed for measurements of stress change and deformation in rock. The fundamental principle of the instrument is to rotate the laser displacement sensor sequentially around a borehole axis and measure the distance from the borehole center to the wall of the borehole for each rotation angle. It has the following features:
1. Measurements can be made without contact way and its principle of measurement is simple.
2. Resolution is high and the range of measurement is wide.
3. Reliability is high because of many measuring points.
4. The geometry of cross-sectional plane in a borehole can be evaluated.
5. Measurements can be made at different depths in the borehole.
The applicability of a borehole meter was investigated through the laboratory tests in the block models with a broken zone or a discontinuity around a borehole.
As a result, the borehole meter was found to be available to the measurement in a situation where the broken zone or discontinuity exists. This means that the versatile monitoring can be performed at any depth of a single borehole in-situ rock mass with only one borehole meter.

抄録全体を表示

　本研究では，緑色凝灰岩が多孔質且つミネラルを豊富に含む点に着目し，緑色凝灰岩の加工廃材を用いたミニトマトとニンジンの栽培試験と土壌の化学性，生物性への影響評価を行った．栽培試験の結果，緑色凝灰岩施用区ではミニトマトの収量とニンジンの根長が有意に増加した（p<0.05）．土壌化学分析の結果，ミニトマト栽培では緑色凝灰岩施用によりNO₃^-–N濃度とCaO濃度が有意に増加した（p<0.05）．16S rRNA遺伝子に基づいた微生物群集構造解析の結果，ミニトマトとニンジンの栽培試験において，緑色凝灰岩施用が検出率0.11%以下のマイナーな微生物群集構造形成に影響を与えることが示唆され，ニンジン栽培では緑色凝灰岩無施用区で土壌劣化を示すKoribacteraceae科が有意に増加した（p<0.05）．

抄録全体を表示