Huge amount of heat below about 200 °C, for example, has been exhausted in vain from various factories. Such unused heat sources including the solar heat must be used effectively to save consumption of fossil fuels. Although we generally encounter many technical difficulties to extract usable heat from such low temperature heat-sources, the zeolite-water-pair, that is, the nonlinear relationship between the vapor pressure and temperature, may give a prospective solution for the heat recovery.As zeolite-researchesstanding especially on the heat recovering aid have been lacking so far, several targets will be pointed out here on the present subject.

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Cobalt-Rich Manganese Deposits (CRMD) is one of underwater mineral resources which is cobalt supply. In order to mine this CRMD efficiently, it is important to understand such engineer properties of CRMD and their substrates, as P-wave velocity, specific gravity, strengths and so on. But these engineering properties have not been well known yet. Because the layer of CRMD is not thicker then 10 centimeter, it is difficult to examine ordinary strength tests such as compression test, tensile test and so on.In this paper, to suggest the way to estimate engineering properties, two hardnesses which are applied to metal materials and specific gravity, porosity and P-wave velocity are measured, and relationship between these two hardnesses and these three properties is examined. One of two hardnesses is Shore hardness test that is the one of dynamic hardness test and the other is Micro-Vickers hardness test that is the one of static hardness test. And more, to suggest the way of continuous estimation of engineering properties, reflection coefficient at the surface of CRMD and their substrates is measured, and relationship between hardnesses and their coefficient is examined. Consequently, the followings become clear.1) Micro-Vickers hardness of CRMD and their substrates has no connection with specific gravity, porosity and P-wave velocity. But Shore hardness is closely connected with these three engineering properties.2) Reflection coefficient of CRMD and their substrates is closely connected with Shore hardness, specific gravity and porosity. It is possible to estimate the engineering properties of CRMD and their substrates using the reflection coefficient.

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When analyzing the lateral vibration of an offshore structure supported by seabed layer, the effect of this layer must be taken into consideration. In this study, first, the natural frequency of lateral vibration of the offshore structure constructed with four legs and a platform was analyzed theoretically by replacing it with the one-leg structure, the upper end of which was loaded by an axial load corresponding to the equivalent mass of a platform per leg and was constrained to move in the horizontal direction only. Furthermore, the validity of this theory was examined by the model experiment. The main results obtained are as follows：(1) The theoretical natural frequency calculated by the method replacing the 4-leg structure with one-leg structure coincides with the experimental one within the difference of 7 %, and so this method is valid even in case that the effect of seabed layer is taken into consideration.(2) In order to calculate the natural frequencies of practical offshore structures with good accuracy, the leg's axial force due to the weight of the platform must be considered, and the leg's own weight may be neglected in case of a shorter-leg structure (L ≦ 75 m in this study) but must be taken into account in case of a longer-leg one.

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The first rock caverns for oil storage in Japan have been constructed in Kuji, Kikuma and Kushikino. Although many phenomena could not maintain the necessary ground water level through some cracks and fractures which occurred during the process of actually constructing the rock caverns, we were able to complete the storage facilities into service by the various measures to render water-sealing effective. As a result, it was confirmed that the observation of the flow trends through water passage is most important to secure the water-sealing system. For this reason, we made the classification and evaluation system to be composed mainly of "Evaluating Water Passages" and "Geological Conditions such as Joint Spacing etc.", how to evaluate jointed rock masses with respect to water-sealing. This paper describes the outline of such classification for aiming and helping the development of water-sealing technology.

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In a previous paper, the authors proposed a corresponding Work Index Wi , c which is proportional to the Work Index Wi . Wi , c can be determined from the zero-order increasing rate constant of the mass fraction finer than a cut size in a ball mill grinding.In this paper, the authors proposed an application of Wi , c to the fine particles such as fly ash of which the Work Index was not defined in JIS. The grinding experiments were carried out using the mill made of alumina with a diameter 144 mm and the grinding balls of alumina with a diameter 20 mm. The maximum size of fly ash used is about 75μm. The relationship between Wi , c of fly ash and the cut size was studied. As the results, Wi , c is approximately constant to a certain cut size but increases below it. Wi , c can be useful for evaluating a grindability of fine particles.

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The extraction of mercury(2) from hydrochloric acid solutions by dihexyl sulphide (DHS, R2S) and dihexyl sulphoxide (DHSO, R2SO) in benzene has been investigated under different conditions. The organic extracts were examined by infrared, Raman and nuclear magnetic resonance spectroscopies. As a result, it was found that with increasing the concentration of aqueous hydrochloric acid solutions, the distribution coefficient for DHS decreases below 1 mol dm-3 acid and its decrease becomes gentle above this acidity；the distribution coefficient for DHSO decreases up to a minimum at 2 mol dm-3 acid and then rises above this acidity. At low aqueous acidity, the behaviour and efficiency for the extraction of mercury(2) by DHS were analogous to those by DHSO and at higher acidities the extraction efficiency of mercury(2) by DHSO is higher than that by DHS. Consequently the following equilibrium equations are proposed for the extraction of mercury(2) from hydrochloric acid solutions：by DHS, HgCl2(aq) + 2R2S(org) →← HgCl2·2R2S(org), and with increasing the loading of mercury(2) HgCl2(aq) + R2S(org) →← HgCl2·R2S(org)；by DHSO , HgCl2(aq) + 2R2SO(org) →← HgCl2·2R2SO(org), HgCl3-(aq) + H+(aq) + 3R2SO(org) →← HHgCl3·3R2SO(org) and HgCl42-(aq) + 2H+(aq) + 2R2SO(org) →← H2HgCl4·2R2SO(org), and when mercury loading increases HgCl2(aq) + R2SO(org) →← HgCl2·R2SO(org).

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The hydrolysis of benzene solutions containing aluminium isopropoxide which is chosen as a representative compound of aluminium alkoxide in contact with water has been examined under different conditions. The precipitates were checked by X-ray diffraction study, infrared spectroscopy and thermal analysis (TG and DTA). It was found that the freshly precipitated gelatinous aluminium hydroxide exists in an amorphous type and goes to pseudoboehmite by ageing in settling, and then proceeds to bayerite. The amount of pseudoboehmite increased with increasing the concentration of aluminium isopropoxide in benzene solution contacted with water and the preparation temperature. In addition, the composition of the precipitate was not much influenced by the initial pH value of water added to benzene solution of aluminium isopropoxide. When the mixture of benzene solution containing aluminium isopropoxide and water was aged in agitation, the formation of hydrargillite was accompanied with that of bayerite. Consequently it is inferred that the crystallization of gelatinous aluminium hydroxide prepared by the hydrolysis of aluminium isopropoxide proceeds in the following sequence :freshly precipitated amorphous aluminium hydroxide → pseudoboehmite →bayerrite→hydrargillite

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A hydrolysis reaction was carried out by adding a certain amount of zinc oxide into the sulphuric acid acidified ferric sulphate solutions with various concentrations at 70 °C, 80 °C, 90 °C, 100 °C and 110 °C respectively for more than 168 hours. The composition of solutions and the precipitation of goethite, which were balanced with solutions at an equilibrium state when the hydrolysis reaction proceeded to completion, were examined. It was found that the precipitation of goethite occurred from the region where ferric ion concentration increased slightly with an increase of the sulphuric acid concentration to the region where ferric ion concentration increased suddenly. In the region where goethite was precipitated, the sulphuric acid concentration in the solution increased with raising temperature, e. g. the precipitation of goethite occurred in the solution with the sulphuric acid concentration up to 8.4 g/l at 70 °C, 11.8 g/l at 80 °C, 15.5 g/l at 90 °C, 16.5 g/l at 100 °C, and 21.0 g/l at 110 °C respectively. The ferric ion concentration increased with an increase of the sulphuric acid concentration at the same temperature, and decreased with raising temperature at the same sulphuric acid concentration. A plot of logarithmic value of sulphuric acid concentration against logarithmic value of ferric ion concentration showed a linear relationship which can be expressed by empirical formulas at the individual temperature.

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Fe-Ni alloy, namely 42 alloy, has made broad use for lead frame in electronic industries. Usually acidic concentrated ferric chloride solutions are used as an etching solution while lead frame is being etched. In an etching process as dissolution of the material goes on, the etching efficiency deteriorates owing that Ni or Fe ions accumulate in the etching solution. In order to keep the etching efficiency a certain level, a fresh etching solution is replaced with a part of the wasted solution to maintain the uniformity of the solution composition. The wasted etching solution contains concentrated Ni and Fe ions. At present, the wasted etching solutions are treated by a precipitation method and then precipitated Ni is used for a material to make stainless steel. It is known that EHO(2-ethylhexanal oxime) is the extractant which has a characteristic to extract Ni prior to Fe. However, no study is performed concerning the precedent extraction of Ni from hydrochloric acid solution.In this study, the recovery of concentrated Ni from used etching solutions with a solvent extraction method was examined and we tried to establish the process to recycle the etching solutions.

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Electroless plating is widely used in electronics, semiconductor and automobile industries as a surface treatment technique, because uniform thickness metal can be deposited on plastics, ceramics or polymers with intricately shaped surfaces. Above all, electroless nickel plating using hypophosphite as a reducing agent is very popular and has been studied a lot, since it gives excellent plated metal surfaces with corrosion resistance, lubricity and magnetic properties. As metal deposition progresses in this process, however, phosphorous acid increases in the plating bath, which causes degradation of the bath solution. Therefore, the bath itself must be disposed after a certain number of turnovers before the degradation occurs. The waste solution from electroless nickel plating bath contains a large quantity of nickel, hypophosphite, phosphite and organic compounds such as citrate, malate or succinate. It is quite harmful to the environment and at the same time, these hazardous wastes can be viewed as resources if properly handled. Therefore, it is very important to develop an effective extraction technique removing these chemical substances separately.In the present study, the application of solvent extraction to the treatment of electroless nickel plating waste water was investigated. In the treatment of caustic alkaline plating waste water, TOMAC is favorable to the extraction of nickel and citrate, and the separation from hypophosphite and phosphite. It is difficult to apply TOMAC to the treatment of ammoniacal alkaline plating waste water, while the use of chelating extractants such as LIX 26 is favorable to extraction of nickel. Meanwhile, the application of solvent extraction to the treatment of acidic plating waste water is difficult.

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