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Various zeolites have been synthesized from coal fly ash (FA) by hydrothermal treatment with NaOH solution. Phillipsite-type zeolite was synthesized selectively from FA (FA-phillipsite), and succeeded in in situ combining the FA-phillipsite with sepiolite to form FA-phillipsite/sepiolite composite. The adsorption behaviour of two harmful heavy metal ions (Pb 2+ and Cd 2+ ) were investigated for the FA-phillipsite and FA-phillipsite/sepiolite composite (30 mass % sepiolite). It was found that the NaOH hydrothermal treatment produced not only phillipsite but also Na + -substituted sepiolite. Both the FA-phillipsite and the FA-phillipsite/sepiolite composite showed high adsorbing-ability for Pb 2+ (2.90 and 2.68 meq g -1 ) and Cd 2+ (1.62 and 1.74 meq g -1 ) ions. The adsorption efficiency of the composite was much higher in the measured value than in the calculated one estimated from the maximum adsorbing-ability of the untreated sepiolite. This indicates that the Na + -substituted sepiolite in the composite has excellent adsorbing-ability for Pb 2+ and Cd 2+ ions. Since sepiolite has superior forming performance, the FA-derived phillipsite/ sepiolite composite powder was able to be molded into various shapes e.g. pellet and tube. The FA-phillipsite/sepiolite composite is expected to be a new adsorbent for practical use.

Some previous studies suggest that aging influences wear and oxidatively degraded nonsterilized ultra-high-molecular-weight polyethylene (UHMWPE) exhibits decreased wear resistance. We therefore asked whether shelf-aging storage conditions influenced degradation and wear resistance of gamma-irradiated UHMWPE. We examined oxidation and wear of 100-Mrad gamma-irradiated UHMWPE (100-Mrad polyethylene) cups shelf-aged for 30 years without (n=2) or with (n=2) packages. The oxidation index of the unpackaged 100-Mrad polyethylene surface (4) was higher than that of the packaged one (2.7). The packaged 100-Mrad polyethylene cup exhibited a high wear resistance with a steady wear rate of 0.5 mg/10(6) cycles. In contrast, the unpackaged 100-Mrad polyethylene exhibited an extremely high initial wear rate of 187.9 mg/10(6) cycles over the first 0.25 x 10(6) cycles with a subsequently reduced wear rate of 5 mg/10(6) cycles after 5 x 10(6) cycles. Packaging over long periods inhibits surface oxidation and maintains the wear resistance of gamma-irradiated UHMWPE cups.

The efficacy of a composite of beta-tricalcium phosphate particles and carboxymethyl-chitin (beta-TCP/CM-chitin) for bone repair has already been established in animal experiments. In the present study, subacute systemic toxicity was evaluated to further assess the biological safety of the implanted composite. beta-TCP/CM-chitin (approximately 4 mg/kg and 7 mg/kg in male and female rats, respectively) was implanted for 28 days into penetrating defects (2 mm diameter) made artificially in the shaft of the right femur of rats. Sham operation groups with the defect only were prepared as controls. Haematology, blood chemistry, urinalysis, and the histopathology of 44 organs and tissues were investigated. Body weight measurements and clinical observations were performed daily throughout the study. No subacute systemic toxicity possibly caused by the implantation of beta-TCP/CM-chitin was detected. These findings indicate that beta-TCP/CM-chitin composite is a highly biocompatible bone substitute, at least with an implantation dosage of < 4-7 mg/kg.

SmFe2.4 alloy thin films were prepared by DC magnetron sputtering process at different substrate temperatures from 323 K to 623 K and at different Ar gas pressure from 0.5 to 1.0 Pa. The magnetostriction increased with decreasing of an Ar gas pressure as sputtering gas. On the other hand, the large magnetostriction was observed at high Ar gas pressure on heating at 623 K of high substrate temperature. The maximum value of magnetostriction over 1400 ppm at 1.2 MA/m was found in a Sm-Fe film prepared at 423 K of substrate temperature and at 0.5 Pa of argon gas pressure. This value was top data for the compressive (negative) magnetostrictive films up to now. From this result, it was concluded that the amount of a magnetostriction was strongly affected by change in the morphology of the thin film.

In this study, the influence of aluminum content on shape memory effect ofTi-7Cr-Al alloys fabricated using low-grade sponge titanium was investigated by measurement of electrical resistivity and Vickers hardness, along with shape-recovery testing. The results obtained are as follows. In the STQed state, the phase constitution of non-Al added alloy, Ti-7Cr-0Al alloy, was found to consist of retained β phase and athermal ω, whereas those of Al added alloys, Ti-7Cr-1.5Al, 3.0Al and 4.5Al alloys, were found to consist oforthorhombic martensite, α", and retained β phase. Resistivity (p) at liquid nitrogen (LN) and room temperature (RT) increased monotonously with Al content. Resistivity ratio (ρ L N /ρ R T ) increased drastically at 3Al, exceeding unity. Shape recovery was exhibited in the 1.5Al, 3.0Al, and 4.5Al alloys having been fabricated using low-grade sponge titanium as raw material. In the 3.0Al and 4.5Al alloys, shape recovery ratio was about 90% at temperatures above 523 K and recovery surface strain was at least 0.03. The resistivity change indicates that stress-induced orthorhombic martensite was produced during bending of the 4.5A1 alloy.

Influences of composition on magenetostriction of Fe–Sm alloy thin films prepared by D.C. magnetron sputtering process were investigated. Composition of formed film was ranged from 24 to 59 at%Sm. Negative, that is, compressive magnetostriction was observed of Fe– Sm thin films. The magenetostriction of thin films was varied with composition rate of Fe–Sm alloy. The giant magnetostriction (GM) over 1000 ppm at 1200 kA/m was observed from 24 to 34 at%Sm for Fe–Sm amorphous film. The limited value of GM at 1200 kA/m was 1280 ppm of Fe–29.3 at%Sm alloy film.

山岳トンネルの掘削にあたり破砕帯などに起因する大規模な集中湧水に遭遇した場合, 沢水の枯渇などの環境問題トンネル施工の工程遅延, 工事費の増加などを招く. しかしながら, 岩盤亀裂中の地下水 (裂か水) の挙動は, 一般に非常に複雑で, その湧出箇所および量の予測は容易ではない. そこで, CSA・MT探査から得られた地山比抵抗分布を用いて, 地山岩盤をモデル化し, トンネル掘削に伴う地下水の挙動変化, トンネル湧水量の変化を予測する手法を構築し, トンネル施工時に岩盤性状および湧水量の変化について検証し, 集中湧水を含め良好な一致をみた. なお, 本報告で採用した湧水量予測システムは水理地質構造的に, (1) 表層モデル, (2) 地下水流動モデル, (3) トンネル湧水量算出モデルから構成されている.

The compound TbFe2 and SmFe2 are known to exhibit the largest positive and negative magnetostriction, receptively. Thin fllms prepared by magnetron sputtering process were obtained film structure showed by Thornton model. The change of this film structure was expected influence of magnetostriction properties. SmFe alloy thin films were prepared by D.C. magnetron sputtering process at different substrate temperatures from 323 K to 623 K and at different argon gas pressure of 0.5 and 0.8 Pa. A magnetostriction of the Sm-Fe alloy film increased with decreasing gas pressure on sputtering. The maximum value of magnetostriction over 1300 ppm at 1.0 MA/m was found in a Sm-Fe film prepared at 423 K of substrate temperature below crystallization temperature and at 0.5 Pa of argon gas pressure.

Composite mover device constructed with both negative and positive magnetostrictive thin films on each side surface of silicon substrate were prepared by DC magnetron sputtering process. The magnetic field induced mover strain (an apparent magnetostriction) of composite mover device at 150 kA/m of magnetic field was as same as the sum of magnetostriction values of Sm-Fe negative and Tb-Fe positive magnetostrictive thin films. Although the magnetostrictive susceptibility of Sm-Fe negative and Tb-Fe positive magnetostrictive thin films were over 8.6 and 5.42 ppm/kA•m-1, respectively, an apparent magnetostrictive susceptibility of the composite mover device was 36.4 ppm/kA•m-1. We concluded that composite process tremendously enhanced the apparent magnetostrictive susceptibility. Composite mover device with high responsiveness was developed.

Influences of composition on magenetostriction of Sm-Fe alloy thin films prepared by D.C. magnetron sputtering process were investigated. Composition of formed film was ranged form 25 to 59 at%Sm. Negative magnetostriction were obtained of amorphous Sm-Fe thin films. The magenetostriction of thin films was varied with composition rate of Sm-Fe alloy. The giant magnetostriction over 1000 ppm at 400 kA/m was observed from 29 to 34 at% for Sm-Fe alloy film. The giant magnetostrictive (Sm-Fe) alloy thin film showed its potential use as wireless actuators in microsystem technology.