An experimental study was carried out on reactive diffusion in the Ni-RE (RE=Ce, Pr, Nd) binary alloy systems for providing fundamental knowledge of the reduction-diffusion (R-D) method to directly produce powders of nickel-rare earth compounds, RENi₅, for use in hydrogen storage materials.
Firstly, phase relations were investigated at temperatures above 1, 000 or 1, 100K and in a concentration range of nickel above 55mol%, using reactive diffusion and metallographic methods. The-following compounds were found in the process of reactive diffusion:(a) the Ni-Ce system-CeNi₂, CeNi₃, Ce₂Ni₇ and CeNi₅ (b). the Ni-Pr system-PrNi₂, PrNi₃, Pr₂Ni₇ and PrNi₅ (c) the Ni-Nd system-NdNi₂, NdNi₃, Nd₂Ni₇, NdNi₄, NdNi₅ and Nd₂Ni₁₅. The compounds of CeNi₅, PrNi₅ and NdNi₅ presented solid solutions, and their solubility limits were determined by an EPMA analysis. The widest ranges of solubility were 82.0-86.4mol% Ni at 1, 488K, 81.7-85.4mol% Ni at 1, 558K and 82.4-86.5mol% Ni at 1, 573K in the Ni-Ce, Ni-Pr and Ni-Nd systems, respectively.
Secondly, interdiffusion coefficients, D, of the PrNi₅ and NdNi₅ compounds were determined, using a diffusion couple of the Ni/Ni-RE melt, and were given as
PrNi₅: D/m²·s^-1=1.61×10^-9·exp (-61.3 kJ·mol^-1/RT)(T=1, 423-1, 513K)
NdNi₅: D/m²·s^-1=1.85×10^-4·exp (-205kJ·mol^-1/RT)(T=1, 443-1, 503K)

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The electrodeposition of Al-Mn alloys from the molten chlorides salts was carried out to discuss the fundamental codeposition behavior.
The effect of a current density on the alloy composition and on the cathode current efficiency was investigated. The result shows characteristic feature that the Mn content in the deposits is kept almost constant at relatively lower current densities. At higher current densities, the Mn content in the deposits shifts to reach another constant values which are depended on the bath composition and determined by the limiting current densities of Al and Mn.
Then, the polarization curves were measured for Al and Al-Mn deposition. Both depositions of Al and Mn from the alloy plating baths occur at the same potential and no potential region where Mn or Al deposited individually is observed. The partial polarization curves for Al deposition show that the potential of Al deposition shifts to less noble direction by 70 mV due to the codeposition with Mn.
Raising temperature promotes the mass transfer of the reactants to increase the limiting current densities of Al and Mn. On the other hand, the Mn content of the deposits increases at higher temperatures.

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The strength usually decreases with increase in the size. The decrease in strength with size may be due to the increase of cracks or flaws in rock specimen. This size effect has much importance in designing most of the underground structures, and much effort has been paid up to date. It is better to test as large specimens as possible, however large size test is time consuming and also very expensive. Only very limited knowledge is available.
In this study, the size effect of rock specimen was simulated and examined by computer simulation where a non-linear constitutive equation was implemented in FEM program. Of course, the constitutive equation can be applied not only to pre-failure region but also postfailure region.
The calculated results indicate that strength of specimen decreases with increase of number of elements in FEM mesh. However, number of elements exceed 100, then strength does not decrease apparently. This trend is quantitatively similar to in-situ test results up to date. The FEM analysis in this study is in 2 dimensional one and the qualitative discussion is still beyond our scope. However, the calculated results looks hopefull and promise future possibility.

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Gas pressure and rock pressure in coal seams are related to the occurrences of a gas outburst. Prediction of a high stress zone in advance of mining enables the selection of a proper countermeasure against a gas outburst, but it takes much time and cost. to measure the underground rock pressure with the mining operations and it is not practical.
In come countries the temperature is measured in order to judge the high stress zone in a coal seam. There are two contradictory ideas about the relationship between temperature and stress in the coal seam; one being that the temperature increases in accordance with the increase of stress, and the other one being that the temperature decreases in accordance with the increase of the stress. These contradictory thoughts come from the following reasons. The temperature rise caused by the stress rise has two reasons. The first one is caused by the direct adiabatic process in coals and rocks and the second one is caused by the low temperature oxidation at the high stress zone where many cracks are generated by the high stress, when the high stress zone is near the surface of the coal seam and the air flows into these cracks. The temperature decrease by the stress rise comes from the gas release from pores in the coal seam having high gas content and gas pressure to the cracks which are generated by the high stress.
To get the fundamental data of the relationship between temperature change and stress change, the author measured the temperature of the coals and rocks obtained in Japanese coal mines by changing the surrounding pressure up to 34 MPa for the confining pressure and the uni-axial compression.
The temperature rise was 0.22-0.46°C/10 MPa for the coals and 0.07-0.25°C/10 MPa for the rocks under confining pressure. These values were too small to apply the measurement of temperature change for the proper prediction of a high stress zone.

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In gas-liquid two-phase flow and gas-liquid-solid three-phase flow, many flow configurations are observed and the particular pattern depends on the flow rates and the physical properties. The knowledge of flow regime is very important in the study of mechanics and modeling of the flows. In the previous investigations the flow pattern has been judged mostly on a basis of visual observation, therefore it was depended on observers subjectively.
In this work volumetric fraction fluctuations of gas phase (in gas-liquid two phase flow) or gas and solid phases (in gas-liquid-solid three-phase flow) were measured by the constant current technique and those probability density functions (PDF) were mathematically expected by the maximum entropy principle. Then the flow regime detemlination was made objectively by using the parameters of the PDFs.The features of the PDF were classified into three dominant flow patterns; bubbly, intermittent and annular flows. It is demonstrated that the regime boundary of transition from the bubbly flow to the intermittent flow is predicted by a semi empirical formula based on the drift flux model and the regime boundary of intermittent-annular transition is described by an empirical correlation based on Froude number.

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Rare earth metal ion was adsorbed by various kind of algal powder. In summary, the adsorption reaction of rare earth metal ion by general species of algal powder, seems to be a kind of cation exchange reaction. However rare earth metal ion fraction adsorbed by chlorella or spirulina was observed to have a maximum value at pH 3-4.5. Therefore, rare earth metal and other common metal could be separated by selective adsorption with chlorella or spirulina.
When the blue pigment extracted from spirulina i. e. SP-blue was used, rare earth metal ion fraction adsorbed increased, while, other common metal ion fraction adsorbed decreased, and the adsorption selectivity became better compared to those by spirulina.
Main component of SP-blue is phycocyanin, which has protein partial structure and pigment partial structure called phycocyanobilin. To clarify the adsorption behavior of rare earth metal ion relating with protein coagulating at varying pH, experiments were carried out with egg white and protein from soy bean, comparing to that of phycocyanin. As a result, metal ion fraction adsorbed by egg white had low value, and seems to be a cation exchanging adsorption behavior. Adsorption behavior of protein from soy bean seems to be between phycocyanin and egg white.
In summary, adsorption behavior of phycocyanin for metal ion is not simply by the coagulation of protein partial structure, but by the specific effect of phycocyanin including pigment partial structure.

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Removal of dispersed kerosene droplets was studied using CaCO (size: 10-20μEm) and quartz (size: 5-10μm) as the hydrophilic solid particles. Amount of the droplets adhesion to the particles and enhancement of coagulation of the particles by adhered oil were examined. Adhesion to particles of unit weight was lowered with increasing addition of the particles. There was a certain correlation between the residual oil concentration and the amount of oil adhesion to particles of unit weight.
Consumption of the particles was effectively decreased by reusing them. Coagulation was enhanced by oil adhesion for all particles used. Water content of the oil-bearing sludge was 30-60% after filtration.

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As a part of the program of fundamental study on the formation of light rare earth-transition metal intermetallic compounds, the formation kinetics of Ce-Fe and Sm-Fe compounds was examined in this work. First, diffusion couples of Ce-Fe and Sm-Fe systems containing Mo wires as markers were vacuum-sealed in silica ampules and maintained at 843K and 963K which are just below their eutectic temperatures, respectively. The CeFe₂ and SmFe₂ were formed between the metal plates, which shows that Ce and Fe were predominant diffusing components in the Ce-Fe and Sm-Fe systems, respectively. Second, an Fe plate was immersed in a Ce-Fe or Sm-Fe melt of which composition was set at each Fe-side liquidus line at a temperature above the eutectic point. The thickness of the compounds formed on the surface of the Fe plate grew in accordance with the parabolic rate law. Only CeFe₂ and SmFe₂ formed, while the formation of Ce₂Fe₁₇, SmFe₃ and Sm₂Fe₁₇ which were indicated in the phase diagrams could not be confirmed at temperatures lower than 1, 100K. The growth rate of SmFe₂ was much higher than that of CeFe₂. In each of the Ce-Fe and Sm-Fe systems the growth rate of a compound decreased and showed a greater dependence on temperature with the increase in Fe content. The growth rate of Sm₂Fe₁₇ at 1, 300K coincided with that measured in the reduction-diffusion process.

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Deformation Rate Analysis (DRA), proposed by Yamamoto, is one of simple methods for measuring in-situ stress at great depth. However, it has not been recognized as a reliable method for lack of the fundamental studies to support DRA.
In this study, to investigate some basic characteristics of DRA, uniaxial, triaxial and hydrostatic pre-stresses were applied to cylindrical specimens of Inada granite and Ogino tuff in a laboratory and then axial stress was evaluated by DRA. The following results were obtained:
(1) The range of uniaxial pre-stress which DRA could evaluated accurately was dependent on rock type. For Inada granite, DRA underestimated the pre-stress when it was higher than the stress at the onset of dilatancy. On the other hand, such a tendency was not observed for Ogino tuff.
(2) As the time passed after pre-loading, the stress evaluated by DRA decreased.
(3) Only when the axis of uniaxial compression for DRA was oriented within 45° from the pre-loading axis, evaluated stress was consistent with the normal stress in that direction.
(4) When the rocks were triaxially pre-stressed, DRA could not evaluate the axial pre-stress but evaluate the axial strain recovery after unloading.
(5) Based on the maximum strain recovery measured by DRA, a new method for measuring three-dimentional in-situ stress was proposed.

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Peak Particle Velocity (PPV) of ground vibration induced by blasting have been used for long time as a standard for evaluating damage of structures. However, in recent years, it is often discussed whether the PPV standard is adequate or not for evaluating public environmental disturbances. In such case, Vibration Level (VL) is used, which is established and defined to allow for the feeling of human body against the acceleration of vibration. Hence the necessity of measurement by both PPV and VL is increasing. If the relation between PPV and VL can be quantitatively clarified, then it is possible to estimate PPV from VL and vice versa. The relation, however, is complicated in case of ground vibration induced by practical delayed blastings because of some factors, namely such as the frequency components and the shape of wave form.
In this paper, firstly, a new method to calculate VL from the velocity wave form was discussed. Through the discussion, many factors were investigated which have to be considered when the vibration wave form is converted into VL. Then such method was applied to measured waves caused by tunnelling blasting in order to evaluate a variation due to each primary factor. As a result, a new relationship equation between PPV and VL for ground vibration due to blasting was proposed.

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Landscape distraction caused by open-cut mining is one of the environmental problems. For the purpose of analysis on landscape of mined-out quarry, evaluative examinations were conducted with semantic differential method. Four mined-out quarries were adopted as subjects of study. They were presented by color slide films and evaluated with 15 pairs of adjective scales by 77 students of Iwate university and 30 citizens of Morioka city. Adjective scales consisted of antonyms, for example “ugly and beautiful”, and were graduated to five stages. From the data of evaluative examination, three kinds of statistical analyses were conducted, namely profile analysis, cluster analysis and factor analysis. In the profile analysis, similarity and adaptation of adjective scales to mined-out quarry became clear qualitatively. In the cluster analysis, it became possible to understand the factor of landscape evaluation of mined-out quarry systematically. In the factor analysis with varimax method, became clear that there were several factors to estimate the landscape evaluation, namely “sense scale”, “balance scale”, “beauty scale” and “natural scale” including “size scale”

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