The science of fullerene, after the discovery of its synthesis and seperation processes, have been developing quite rapidly. This review surveys the basic trend of its progress especially from the materials science view points and future aspects are discussed. In addition to C₆₀, the higher fullerenes C_n (n≥70) and metal doped fullerene M_m^@C₈₂ are also included. Discussion is made on fullerene related materials such as carbon nanotubes and nanocapsules.

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A review has been given on the development and problems of thermal analysis with emphasis on the pioneering works in Japan and theoretical aspects. Japanese scientists have played an important part in the development of thermal analysis, which includes improvements of the sample holder and thermocouple system in differential thermal analysis (DTA), and original ideas and approaches in thermogravimetry (TG) and evolved gas analysis (EGA).
In differential scanning calorimetry (DSC), the actual sample temperature is different from the recorded temperature because the temperature measurement is made outside the sample. The temperature-lag of the sample can be theoretically evaluated for the first-order phase transition. A principle of the base line drawing is given for determining the enthalpy of the first-order phase transition in which the heat capacity of the sample is different before and after the transition. The enthalpy of the transition is obtained from the area enclosed by the base line thus drawn and the recorded peak.
In TG technique, the temperature-lag is also significant if the sample temperature is measured by a thermocouple located outside the sample container in the furnace. The temperature reading has been proposed to be calibrated against a thermocouple positioned at the same place of the sample container in the furnace. The EGA is a powerful tool in the study of complex solid-gas reactions, especially as a simultaneous technique coupled with TG.

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Chloride ion at concentration above 100 ppm causes serious problems in zinc electrowinning. Electrolytic oxidation method is effective for eliminating the anion. Diffusion controls the rate of such elimination. Diffusivity has been examined by voltammetry with Pt/Ti stationary and rotating disk electrodes. Current-potential curves recorded by both techniques show that the characteristic current follows the Randles-Sevcik or Levich equations. From the coefficients appearing in these equations, diffusivity of chloride ion, for example, 1.2×10^-9m²·s^-1 in a 10mol·m^-3 ZnCl₂/1.0 kmol·m^-3 ZnSO₄ mixture containing 1.5 kmol·m^-3 H2SO₄, was determined. Viscosity was also determined with a capillary type of viscometer. The product of diffusivity and viscosity assumes a constant value (1.8×10^-12N). An increase in zinc sulfate concentration is accompanied by a decrease in diffusivity, and the phenomenon is attributed to an increase in viscosity. The relationship between these two parameters makes it possible to estimate the magnitude of diffusivity by measuring viscosity.

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A mixed CO₂2-N₂ gas was injected into an aqueous NaOH solution with acrylic resin particles of 190, 550 and 1, 120 μm in average diameters, and the absorption rate of CO₂ gas was measured. It was observed that a cavity was formed on the liquid surface and the plume where the gas penetrates into the liquid accompanying particles, was formed below the cavity. The overall rate of mass transfer of CO₂ gas into the NaOH solution was controlled by mass transfer, and the value of the overall mass transfer parameter, AK₀, varied in the range from 30 to 100 [cm³/s]. CO₂ gas is absorbed in both the cavity and the plume. The ratio of CO₂ gas absorption rate in the plume region to that at the cavity ranged from 0.3 to 1.9 and the ratio increased with the increase in the particle diameter and with the decrease in gas velocity.

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Titrations and surface tension measurements were carried out to investigate the chemical properties of n-tallow-1, 3-diaminopropane dioleate (TDO). Flotation tests with TDO were conducted using a special apparatus and method developed to simulate real flotation in the mixed minerals system of fluorite, barite, calcite, bastnaesite and monazite.
TDO preferentially reacted with La ions compared with Ca ions. Surface tension of TDO aqueous solution was low in the range of pH 5-10, where TDO is present as ampho-ion. High flotation recovery of all minerals was obtained in the same pH range. The flotation behavior in the mixed minerals system was similar to that in the singular mineral systems, because TDO did not easily react with main ions such as Ca ions in the flotation pulp. When TDO addition and pH were optimum, selective flotation was performed without modifiers.

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The SO_X gas sensor utilizing beta-alumina as a solid electrolyte has a rigid theoretical background and produces a reliable emf corresponding to SO₂ gas partial pressure, P_SO2. However, its emf response to a change in P_SO2 is not as fast as that to other electrolytes. In the present study, in order to improve the chemical properties of the surface of the beta-alumina disc, praseodymium was sputtered on both sides through a stainless steel net and oxidized in air. The SO₂ gas sensor utilizing the Na⁺-β-alumina disk covered by Pr₆O₁₁ was tested at 873 and 1, 023 K and compared with the performance utilizing β-alumina uncovered. There was a significant difference in the emf's at 1, 023 K. The hysteresis of the emf's at 873 K with a change in P_SO2 was significantly reduced by the coverage, that is, the coverage with Pr6O11 thin film improved the performance of SO_X sensor at a low temperature. The Pr₆O₁₁ thin film may reduce the vaporization of Na₂O from β-alumina and also the absorption of water vapor by β-alumina. In the mixtures of Pr₆O₁₁ and β-alumina powders annealed at 1, 073K, a compound was detected by means of the X-ray diffraction method with a diffractometer. The formation was very slow with time, and had an essentially negligible effect on the performance of the SO_X sensor. A significant difference in the response speed was not observed. The response speed should be investigated by changing the kind of rare-earth oxide thin film.

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The vapour pressures of SnS in the molten Cu₂S-FeS-SnS system have been measured by means of the transportation method. The data obtained was used to calculate the activities and slight negative deviations of ^aCu₂S, ^aFeS and ^aSnS from ideality were observed in the molten Cu₂S-FeS-SnS system.
Also, the distribution behaviour of tin between the matte and silica-saturated slag was investigated under the controlled partial pressures of SO₂ at 1, 250°C. From the results obtained it was found that tin was concentrated in the matte phase in general, but with increasing matte grade, tin became concentrated in the slag phase. The activity coefficient of SnO in the slag equilibrating with the matte was calculated by thermodynamic analysis.

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This paper describes a method for quantitative analysis of free silica in workshop-dust by the Foulier Transform Infrared Spectrophotometer (FT-IR). Two conventional methods have been used for quantitative analysis of free silica in dust sample, such as the phospholic acid method and the X-ray diffraction method. But these methods are time-consuming and require a large amount of samples. The present FT-IR method enables rapid analysis with very small amount of dust sample and saving time, and is suitable even for fine particles.
In the KBr tablet method, the most popular analytical method for powder sample, we used the infrared absorbance peak which wave number is 800 cm ^-1 for the quantitative analysis of free silica. In Internal Standard method, calsium sulfide is used as the internal standard sample, which wave number of reference peak is 1, 620 cm^-1. The Internal standard method is useful for the samples of low quartz content.
For the sample including kaolinite contaminant which has the same absorbance band with quartz, we can estimate the quartz content of the sample by reducing the intensity of kaolinite at 800 cm^-1 from the intensity of sample at that wave number.

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In this study the reversible and irreversible changes in gas permeability of coal have been investigated by applying the acoustic emission methods in order to find a clue to the advancement of gas drainage technology. Actually, the hysteresis of gas permeation rate appeared between the processes of an increase and decrease of applied gas pressure as a result of an increase in acoustic emission activity. The hysteresis was negligibly small and the reversibility was approximately applicable to the relations between permeation rate and applied gas pressure when the amplitude-frequency distribution of acoustic emissions consisted of a simple straight line. On the basis of this reversibility, the opening rate of gas permeable cracks was considered from the characteristic curves of gas permeation rate. Consequently, it became clear that gas permeability of coal depended on the opening or closing of permeable cracks caused by gas pressure in these cracks. This functional relation was expressed by a new gas permeation formula of coal.

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A new highly efficient conveyance system, which transports reclamation materials using compressed air to gallery in abandoned mine, has been developed. With this new system, the volume density increased more than twice, from 0.37 to 0.79. Moreover, the pressure loss decreased at the rate of 1/150, from 3.28×10⁷Pa to 2.25 ×10⁵Pa, compared with a conventional slurry conveyance system. In the conventional system, a significant amount of water is added to the reclamation materials. The volume density must be so low, otherwise the reclamation materials is too viscous to be conveyed.
The purpose of this study is to solve the problem inherent in conventional systems; a high performance system requires high volume density, however, the volume density can not be increase because the friction between the reclamation materials and pipe increases with the density.
The essential feature of this new conveyance system is the generation of the fluid dynamic controlled slug flow by mixing reclamation materials with air. The addition of air decreases the friction between reclamation materials and the pipe, resulting in a high volume density system.
Finally, a proper quantity of air has been discussed from the view point of conveyance efficiency.

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The kinetics of the bioleaching of pyrite by iron-oxidizing bacterium, Thiobacillus ferrooxidans was studied three mineral samples from the Yanahara, Hanaoka and Uchinotai Mines. Bioleaching experiments were at 30°C and pH 2 in a well-mixed batch reactor, along with adsorption experiments of the bacteria to pyrite samples. The adsorption equilibrium data were analyzed to evaluate the maximum adsorption capacity the equilibrium constant in the Langmuir isotherm. The bacterial adsorption parameters were practically to one another in magnitude. The experimental data for the time-variation of liquid-phase concentrations iron leached and free bacteria were consistent with our kinetic model previously proposed for bioleaching of minerals. The kinetic parameters appearing in the model, the growth yield and specific growth rate of adsorbed bacteria, were evaluated by curve-fitting using the experimental data. The evaluated kinetic parameters unaffected by difference in the crystallinity of pyrite from different localities. Thus, nearly identical bioleaching rates were achieved in the different pyrite samples.

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It has been observed in many cases that anelastic strain change on hemisphericalborehole bottom follows instantaneous elastic strain relief by overcoring and it lasts a couple of days depending on in-situ stress state rock type. Three dimensional principal strain orientations obtained from the time-dependent strains agreed with the one from the instantaneous elastic relief strains. In-situ measurement of both instantaneous and dependent strains on conical borehole bottom have indicated that the time-dependent maximum expansion core reflects the maximum stress state when the core was retrieved. The time-dependent strain variations, therefore, can not always be used to provide a reliable estimate of in-situ stress when the principal stress orientation at the poisson expansion behavior dose not agree with in-situ stress.

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At three boring sites, principal strain orientations obtained from anelastic strain recovery on core surface were compared with in-situ stress states determined by overcoring or hydraulic fracturing method. Orientations of time-dependent maximum expansion of a core taken from the vicinity of a large mined goaf indicated that they presumably reflected the maximum stress state when the core was retrieved and they were totally different from the stress orientations determined by overcoring technique. Three dimensional principal strain orientations obtained from anelastic strain recovery on surface of granodiorite cores (150mm in diameter) were in good agreement with the in-situ stress state predicted by overcoring method. And anelastic strain recovery measurements on Mannari granite were carried out immediately after the 38 mm diameter cores were removed from 300 m deep borehole, where none of three principal axes of strain coincided with the borehole axis. Laboratory measurements of compressional velocity on relaxed Mannari cores showed that the direction of the slowest velocity correlated with the one of maximum expansion and the strike of microcracks in quartz crystals. Then it is suggested that three dimensional stress state can be determined by combination of hydraulic fracturing test at single borehole section and observation of anelastic strain variations of the core taken from the borehole.

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資源と素材 (Vol.109 No.10 p.811) の論文「ECHO細粒用メタルジグによる自動車スクラップからの非鉄金属の回収」中, 著者名に誤りがありました。謹んでお詫びし, 以下のように訂正いたします。 （誤）三又學 （正）二又學

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