The first is described the situation at present and in future for various energies and materials as to Energy, with regard to Energy in general, fossil fuel, specially Coal Utilization, Saving Energy, New Energies and Atmic Energies, and Materials for Energy regarding Supertemperature, Superconductor and so on.
The second is several Proposals with regard to political and technical matters.
And the last is emphasized Harmony and Best Mixture among energies for Happines of human being.

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The present study deals with instrumentation for measuring tool force and twist exerted on a disc cutter which is penetrated into rock with a plunge angle and rolled along a circular truck. The plunge angle of disc cutter was chosen as a control variable, ranging from 0 to 30 degrees. The Investigation ha s provided the experimental formulae for predicting the tool force imposed on inclined disc cutter including TBM gauge cutters as follows:
(a) thrust F_T=K_T tan (φ/2+α)P^1/2,
(b) rolling force F_R=K_R tan (φ/2+α)P,
(c) lateral force F_L=K_L tan (φ/2+α) tan αP^3/2,
where P is disc penetration, φ is the edge angle of disc, α is a plunge angle of disc against rock surface, and K_T, K_R and K_L are constants. Moreover, themeasurement has shown that the twist about the direction of thrust should be accompanied by tool force whenever a disc cutter is penetrated into rock with someplunge angle. These results allow us to comprehend the reason why gauge cuttersand peripheral cutters have experienced much more trobles than face cutters duringtunnelling operation with TBMs, and their operational life-spans are in general shorter than those of face cutters.

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Microcracking and micro-damage model in fine-grained homogeneous marble was simulated with a basis on the stress intensity factors, and investigated by experimental system designed newly. The model allows for the growth of microcracks from starting microcracks, that is, triple-point junctions on a regular array of pre-existing grain boundary microcracks. Axial grain boundary microcracks of the mode I type begin to grow at the onset of sliding in inclined microcracks, which isthe dominant mechanism of microcrack damage. This growth occurs rapidly along the K_I (1) concentration paths created by the grain boundaries. Thus we can observeboth sliding for the inclined grain boundaries and opening for the microcracks which are parallel to the stress σ₁.
A microcrack damaged zone is developed by the dislocation of calcite in marble resulted from the sliding. Thus, thedamaged zone depends on confining pressure, and resultingly, the highly damaged areadecreases with increasing confining pressure.

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Pairs of deep longitudinal slots were made by abrasive water jet from the insideof boreholes which were drilled in large mortar specimens. Confining pressures were applied to the specimens by flatjacks and a loading frame. Hydraulic fracturing tests were carried out in the sections including the slots and the fractureson the plane of prolongation of the slots were produced. Shut-in pressures of the fractures were then measured. Numerical simulation of fracture extension by internal pressurization at the borehole section in an infinite elastic solid was also carried out. In this report, the experimental and numerical results are presented.

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In this research the effects of oxygen, ferric ion and temperature on the magnetite formation were studied. Through these experiments, the end of oxidation timecould be predicted by monitoring the Eh changes of Fe (OH)₂ suspensions. By addition of ferric ion into the Fe (OH)₂ suspensions, the magnetite formation occured instantly and the particle size of the magnetite was under 100Å homogeneously. Through the titration experiments with 2mol/l-NaOH in the mixed solution of Fe (III) and Fe (II), the mechanism of the magnetite formation can be proposed to a solid-solid reaction as follows:
2Fe (OH)₃(s)+Fe(OH)₂(s)→Fe₃O₄+4H₂O

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Reaction mechanism of magnetite formation was investigated by two different methods such as 1) Pouring Fe (OH) ₃ suspension in Fe (OH) ₂ suspension and 2) Mechanically mixing Fe (OH) ₃ powders with Fe (OH) ₂ cake which has minimum water content.
Ultrafine magnetite having particlesize around 100Å was obtained by using both methods in a nitrogen filled glove box. The mechanism of magnetite formation from the Fe (OH) ₂ and Fe (OH) ₃ suspension was determined to be a solid-solid reaction. It was also found that the magnetite by agitating Fe (OH) ₂ and Fe (OH) ₃ suspension at pH 9.0, had the approprite particles for the practical use asthe magnetic fluid.

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The extraction of ruthenium (III) from hydrochloric acid solutions has been investigated by using a trioctylmethylammonium chloride (R₃R'NCl) in various diluents.
The extraction isotherm shows a minimum value at 1.5-2mol dm^-3 in initialaqueous hydrochloric acid solution. Hence, it is suggestedthat the extraction species varies in low acidity (≥1.5 mol dm^-3 HC1) and higher acidity (≤1.5 mol dm^-3). Stoichiometric compositionof the complexes formed in the organic phase deduced to be R₃ R'NRu (OH) ₂Cl₂·2H₂O at low acidity and R₃R' NRuOCl₂·H₂O at higher acidity. These results are also confirmed by infrared spectral measurement of the extracts.
In the examination of diluents effects, chlorobenzeneand o-dichlorobenzene most promoted the extraction of Ru (III) at low and higher acidities, respectively.
The distribution ratios increase with increasing temperature in the both acidities.

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Vanadium diboride (VB₂) film has been synthesized on mild steel and transparent quartz substrates by CVD method, which was carried out at the temperature range of 1073 to 1223K with the hydrogen reduction of VOCl₃-BCl₃ mixture under the chemical erquivalent ratio regions of 10 to 40 for H₂-VOCl₃ gases and of 40 to 120 for H₂-BCl₃ gases. VB₂ film involving both Fe₂B and FeB was synthesized on a mild steel substrate because a mild steel plate was borided with BCl₃ gas. On the other hand, pure VB₂ layer film was prepared on a transparent quartz substrate atthe temperature above 1173K. Futhermore, VB₂ film having high orientation and crystallization could not be prepared on a mild steel substrate. However, smooth surface VB₂ film having high crystallization and micro-vickers hardness of about 2800Hmv could be synthesized on a transparent quartz substrate at the temperature of 1173K under the conditions of chemical equivalent ratio of 40 for H₂-VOCl₃ gases and of 80 for H₂-BCl₃ gases.

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Electric-arc ignition test of methane gas has been carried out for some capacitive-resistive circuit models. The results of the minmum ignition voltages (V_m) for circuits with paticular parameters and with the discharged energy values, has been evaluated. The main results obtained are as follows;
(1) Capacitive-resistive circuit connected with a power-supply is more liable to ignite methane than that without a power-supply in certain conditions.
(2) Discharging resister R 2 and bleeder R 3 act to raise up the V_m, or enlarge the safety V-C zone.
(3) The spark duration is found to be 50μ sec by means of both high-speed cameras and observation of sparking current.
(4) The discharging energies for different capacitor values are found in consideration of the capacitordischarging character in the model with sparking duration of 50μsec.
(5) An easier method is proposed for calculating V_m.
(6) The theoretically obtainned values of V_m coincide with measured ones.

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The waste water treatment in mineral processing involves separation of suspendedparticles in aqueous suspension. One of the most used method making settling velocity of the fine particles faster is flocculation. However, to establish this method as a engineering technique, the flocculation phenomenon of fine particles should be clarified. With this purpose, further investigationswere made using quartz and fluorite particles which are negatively and positively charged respectively in aqueous solution.
Experiments were carried out on pure menerals and on a mixture in equal and different propotion of quartz and fluorite particles. In the experiments conducted with pure minerals varying the pH value of quartz and fluorite particles, it was noticed that in contrast to quartz particles which were dispersed for all pH value, fluorite particles was flocculated in the alkaline range of pH over 9. In the experiments conducted with mixture of minerals, variation of the pH value of the aqueous suspension containing equal quantities of quartz and fluorite had led to the heteroflocculation of particles in a range of pH below 9. The pH value of aqueous suspension were fixed and the proportion of quartz and fluorite particles in the mixture (Qw%) were varied. In this case, the heteroflocculation occurred from Qw 60% to 20% in a range of acid and neutral value of pH and from Qw 40% to 10% in the range of alkali value. As a result of these investigations, a possible heteroflocculation model was proposed for quartz and fluorite particles system in alkaline media.

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The compact overcoring method is proposed for the cost effective stress relieving, of which the diameter equals to that of the pilot boring for in situ stress measurements. This is successfully combined with the conical-ended borehole technique to determine the stress tensor with a high accuracy. Subsequently the axialloading experiment in a conical -ended borehole is presented to evaluat e the elastic moduli of the rock, which are essential to determine the magnitude of the stress tensor.
It is firstly shown how the strains on the bottom surface can be measured by means of the compact overcoring method. The measurement system tobe used in practice has been presented and the excellent accuracy is discussed, analyzing case examples. Conical diamond bits to convert the bottom into a required shape, a borehole bottom scope to survey the crack distribution, a conical strain-cell and a spring-type bonding device to bond the necessary strain gaugesdirectly to the rock surface have been developed successfully as well as a thin-well core-bit for a cost effective stress relieving. From their successful application and subsequent monitoring of the changes in strain with the compact overcoring by the continuous strain measurement system, it is concluded that the present combined method can be used effectively in an isotropic rock mass.
Secondly it is shown how the elastic moduli of the rock can be determined prior to the stress relieving by means of the axial uniform loading on an appointed ring ina conical-ended borehole. The pressure-strain relationships have been analyzed by FEM and the procedure to determine the elastic moduli has been presented as well as the necessary strain coefficients. From the experiments in situ and the subsequent comparision with the conventional laboratory tests, it is concluded that the axial loading procedure is available for the Young's modulus determination.

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The rare earth magnet has a good performance, and the production is increasing year by year. Two types of rare earth magnets are presently made as industrial products. One is a Nd-Fe-B intermetallic compound magnet and the other is a Sm-Coalloy magnet.
The mixed scraps of Nd-Fe-B intermetallic compound and Sm-Co alloy are sometimes produced in the step of production, and the magnets are discarded owing to the deterioration of them and the products equipped with them and they are consequently expected to collect as the mixed scraps of them in the future.
In the present study, acid leaching of the oxidizing roasted products of Nd-Fe-B intermetallic compound and Sm-Co alloy is tested to obtain the fundamental data for the treatment of the mixed rare earth magnet scraps. The results obtained in this study are summarized as follows:
The leaching rate of Nd from the oxidizing roasted product of Nd-Fe-B intermetallic compound with hydrochloricacid and the leaching rates of Sm, Co and Fe from the oxidizing roasted product of Sm-Co alloy with hydrochloric acid and sulfuric acid are represented by the volume reaction model.
The activation energy of these leaching reactions are over 41kj·mol^-1 and the extraction of these metals are not affected by the stirring speeds, therefore it is considered that these leaching reactions are chemically controlled.

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With a great increase in the power of digital computer, the methods of numericalanalysis for the engineering purpose have been developed in the last decades. Especially, the stress analysis is one of the most popular application of numerical methods. The calculated results of the stress analysis are usually visualized by (principal) stress contour. However, for a material of which strength dependson such as confining pressure, stress is not enough to estimate the degree of safety. In such cases, stress severity or local safety factor is used to visualizethe state of stress at any portion in the structure.
In this paper, the stress severity Sv and the safety factor Sf are extended and redefined as;
Sv=d/D & Sf=D/d
where d is distance from the origin to a point (σ1, σ2, σ3) in the stress-coordinate system. If stress increases along the given stress path andreaches to the plane of failure criterion at a point (σ1', σ2'sigma;3'), Dis distance from the origin to this point.The definition of Sv & Sf are quite simple and the values of them can be easily calculated. It should be noted that failure criterion and stress path can be chosen freely and independently.
The modified definition of Sv & Sf is examined comparing with the former definitions such as one by Fairhurst. It is revealed that Sv & Sf calculated following the modified definition is conformable to the former three popular ones and it can be said that the proposed definition is an extended version and upper-compatible to the former ones.

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