Commonly called limestone, calcium carbonate is abundant in Japan and it is amply supplied to industries such as steel making, cement manufacturing and raw material of calcium compound. The authors have been performing a series of fundamental studies concerning a development of novel functional materials of calcium compound. It is necessary to control properties such as crystal size, crystal shape, structure and surface in order to improve their functions. Thus there are very many factors to be taken into consideration concerning particle design.
Amorphous calcium compound is an unstable precussor, much more soluble in water than the crystal system. They can be easily transformed to crystal by placing them in water or various types of aqueous solutions. In particular, their property is expected as raw material for performing particle design of calcium compound. The preparation of artificial biomaterial attaches importance to the approach of new functional materials of calcium compound for the furture. The present work is discussed on the conception of particle design of calcium compound and its fundamental techniques.

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A sustainable supply of mineral resources is currently a world-wide problem which needs to be solved by modern civilization. With the enormous growth of industrialization, the annual output of metals increased exponentially after 1950. Trends and forcasts in the supply-demand of copper, one of the leading base metals, are examined based on a few components of the exponential growth. The results are smmarized as follows:
1) The annual output of copper has increased dramatically over the past 160 years. Low positive and stable long-term growth rates occurred before 1950, whereas growth rates increased quickly and radically after 1950, especially during the 1950-1973 period. A substantial decline in the growth of copper consumption took place in 1975 and lasted until the early 1980s. However, copper consumption has increased again recently.
2) The relationships among GDP growth, copper consumption per constant dollar of GDP and copper consumption per capita were illustrated based on statistical data on copper production in 35 countries over the 1970-1990 period. In general, growth rates of copper consumption per constant dollar of GDP were very high in most developing countries ranging to less than 1, 000 1989, US per capita GDP, while in developed countries, the ranges were more than 5, 000 1989 US per capita GDP, rates of copper consumption per 1989 US $ of GDP fell as per capita GDP increases. However, per capita copper consumption showed a tendency to increase in proportion to the increases in per capita GDP.
3) Copper consumption is also increased by an increasing population. The world's population continues to grow rapidly, driven by very high growth rates in developing countries, although growth rates have dropped sharply in developed countries. However, the per capita consumption of copper in developed countries is remarkably large, whereas that in developing countries is low. The amount by which copper consumption increases is low compared with the growth rate of the world's population.
4) Another component of the exponential growth is the rising standard of living. The per capita consumption of copper in industrialized countries or newly industrializing economies is high, while that in developing countries is low. If the living standard of India or China (with over one-third of the world's population) equated that of Japan or the USA, a huge amount of copper would be needed to support that society. The growth rate of copper consumption would be affected most by the index of the rising standard of living.

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Practical use of high pressure water jets as a tool for rock cutting and drilling has become seriously accepted within the last decade, and the water jet technology is in the improvement stage for practical application. Then, the interest in the cutting mechanism is growing greater, and the precise method to evaluate the structure of water jets impinging onto the rock surface is required for the clarification of the fracture mechanism of rock.In the present paper, the impact force that is the resultant force imposed upon a solid target by water jet impinging normally is analyzed to estimate the incident velocity and the apparent density of cylindrical water jets.
Firstly, the mean velocity of incident jet is determined from the time-average of the impact f orce: Fo, measured using a flat target of erosionless, basing upon the law of momentum.Case examples show that the present procedure is effective for determining the attenuation profile and in detecting the speed reduction associated with the generation of the atmospheric shock wave.
Secondary, the time-dependent erosion of the target is analyzed.The erosion effect upon the impact force is examined by numerical calculations which describe the fluid dynamics of water jet within a cylindrical hole drilled by the water jet impact.The numerical results are compared favorably with the experiments using erosive targets, and it is clarified that the time-average of impact force: F_h is a function of the time of water jet impinging, as shown in Fig.11, and that the terminal ratio: F_h/F_o is associated with the diametral ratio of the hole and the incident jet: D₂/d_o, as shown in Fig.14.Such a relationship is discussed to be useful for the evaluation of the apparent density of water jets.

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In order to solve a flow problem using the conservation equations, it is necessary to give a set of constitutive equations. It is the purpose of this work to investigate the constitutive equations for onedimensional gas-liquid-solid three-phase flow in vertical pipes with a mixture model. In the previous paper, we have investigated average velocities and average volumetric fractions of each phase. In this paper, we discuss wall shear stress and pressure drops experimentally.
The experiments were carried out by using air, water and solid particles. The ranges of volumetric fluxes of air, water and solid particles were 0≤J_G≤10m/s, 0.45≤J_L≤3m/s and 0≤J_s≤0.50m/s, respectively. The frictional pressure drop in gas-liquid-solid three-phase flow could be calculated by the applications of the modified Lockhart-Martinelli method together with some correlations suitable for gas-liquid and liquid-solid two-phase flows.And the relation between frictional, hydrostatic, acceleraion, and total pressure drops was analyzed numerically.

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The purposes of this work are to develop a method of numerical simulation for gas-liquid-solid threephase flow systems and to confirm a method of estimating performance of air-lift pump for deep sea mining. Finite difference equations for the numerical analysis were derived by integration of the partial differential equations based on the drift flux model for three-phase flow with control volumes.The method of the numerical procedure is based on the so-called SIMPLER algorithm proposed by Patankar.
To prove the present numerical procedure, calculations were compared with experimental resultswhich had been obtained with the relatively large air-lift pump by Saito et al. and Weber et al. The present method gave good predictions.

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This paper proposes a method for three dimensional shape measuring and generation of model of piled ore for scooping task planning.
The shape measuring system consists of laser emitter and CCD camera. Three dimensional position of laser spots on the pile is detected based on trigonometry by the measuring system. To shorten the measuring time, number of measuring points is determined by preliminary measuring and adequate measuring points location.
From discrete measuring points, continuous shape is generated by interpolation with triangles of measuring points. The shape of shadow region is estimated based on inclination of slope in the measured region. Through the interpolation and estimation, the column model which is proposed previously by one of the authors is generated.
The result of small scale experiment in laboratory shows that the estimated shape agrees with the measured shape very well especially in the front side shape and the contour at floor. The proposed measuring and modeling method could be applied to a model-based scooping system.

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Synthesized smectite particles have been dispersed in methylphenyl silicon oil. The prepared fluid is stable in a gravitational field. The viscosity of this fluid under electric field has been investigated by many parameters as follows, smectite content in silicon oil, shear rate, electric field strength, frequency of electric field or DC field, temperature of fluid, frequency on viscoelasticity, response time, stability and durability, and so on. The shear stress and current density have increased almost in proportion to a square of electric field strength. The dynamic modulus and dynamic loss change much more in the fluid dispersing lower smectite concentration by applying electric field. For the durability of fluid the viscosity is almost same for several hours under 2kV/mm. This fluid is expected to use in the damper, actuators and so on.

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In order to elucidate the gas jetting phenomena upon a liquid such as a cavity formation and splashing of liquid, an energy balance equation has been derived, where the total gas cavity energy is the sum of a cavity potential energy and a cavity surface energy increment. A linear relationship between those sum per unit cavity volume and the energy density at the nozzle lance exit over liquid were observed and the effective energy coefficient for utilization for inlet energy has been derived as a function of a dimensionless lance height. This paper also discuss the effects of surface tension and viscosity of a liquid as well as that of inlet gas over cavity formation behavior and splashing caused by gas jetting over a liquid.

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In order to obtain the fundamental information regarding a new zinc smelting process where zinc is extracted using molten copper as a solvent, the activity of zinc and two-phase region in the Cu-Zn-Fe ternary system were investigated by using the transportation method and the quenching technique respectively.
The two-phase of molten Cu-Zn alloy and solid iron determined in this study extends widely in the composition region below 70 at% Zn at 1, 473 K in the Cu-Zn-Fe ternary system. The iron solubility in the Cu-Zn alloy exhibits constancy and is nearly 5.5 at% below 40 at % Zn in the molten alloy phase.
The relation between the excess partial molar free energy of zinc, ΔG_Zn^XS and (1-N_Zn) ² on the constant composition ratio of N_Fe/(N_Fe+N_Fe) in the homogeneous melt may be expressed by a line, even if the free energies were calculated from the activity measurements at various temperatures between 1, 123 and 1, 373 K. The activity coefficients of zinc, extrapolated by using the relationship between ΔG_Zn^XS and (1-N_Zn) ², decrease with increasing iron content in the composition region below 60 at%Zn at 1, 473 K. Above this composition range, the activity coefficient increases.
The large solubility of zinc in a molten copper phase is not expected for the new zinc smelting process, because the vapour pressure of zinc is very high even in the composition region of low zinc content in the Cu-Zn-Fe ternary system. Then, the extraction process would require large amount of molten copper to extract zinc from its sinter.

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Xenotime, monazite and ion exchange ores were reacted with NaOH solution in the micro-autoclave under high temperature and pressure to produce a mixture of rare earth hydroxides. The decomposition reaction of phosphate ores such as xenotime and monazite required higher temperature and NaOH concentration than those for the decomposition of carbonatite ore, bastnaesite. The recovery of phosphate from the ores was limited by the solubility of Na₃PO₄ in the NaOH solution. The recovery of yittrium was decreased with the increase in the reaction temperature because the equilibrium phase changed from Y (OH) ₃ to YOOH above 610 K, which was determined by the experiment.

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The solubility of goethite into the sulphuric acid solutions with various types of concentration has been examined from 70°C to 110°C. The goethite used as samples in present experiment was obtained by precipitating from ferric sulphate solutions with the addition of zinc oxide above 80°C for more than 150 hours.
The results obtained were as follows: 1. With the individual temperatures, the ferric ion concentration increased with increasing the sulphuric acid concentration in the solution.
2. The concentration of the ferric ion dissolved into a sulphuric acid solution with the same concentration decreased with increasing temperature.
3. The relationship between the sulphuric acid concentration and the ferric ion concentration at the temperatures of 70, 80, 90, 100, and 110°C is expressed with the empirical formulas shown below.
log [Fe³⁺ (g/l)]=3.86log [H₂SO₄ (g/l)]-2.93, at 70°C
log [Fe³⁺ (g/l)]=3.10log [H₂SO₄ (g/l)]-2.94, at 80°C
log [Fe³⁺ (g/l)]=3.20log [H₂SO₄ (g/l)]-3.12, at 90°C
log [Fe³⁺ (g/l)]=3.39log [H₂SO₄ (g/l)]-3.53, at 100°C
log [Fe³⁺ (g/l)]=4.28log [H₂SO₄ (g/l)]-4.84, at 110°C

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