Variation of longitudinal wave velocity with respect to water saturation was measured for twenty seven kinds of granites by ultrasonic pulse method at room temperature and atomospheric pressure, and therelationships among grain size, shape of pore and longitudinal wave velocity were investigated. Kuster's expressions for bulk and shear moduli were applied to estimate the shape of pore in granite.
The main results obtained are as follows:
1) The effect of water saturation on the longitudinal wave velocity is comparatively larger for granites than other types of rocks such as volcanic and sedimentary rocks. The velocity difference betweensaturated and dry states increases with increasing effective porosity, and does not depend on grain size.
2) The indices of granites, which mean the velocity change corresponding 1% effective porosity, indicate 0.87-3.48.The values of aspect ratio estimated based on the Kuster's expressions are 3.6-16.5×10^-3. It is therefore assumed that the large indices are caused by the fact that the shape of pore in granite is in the form of cracks.
3) The values of aspect ratio of pores in granites are larger than those of crystalline limestones, and have no correlation with grain size. These facts suggest that the velocity difference in granite mainly depends on the effective porosity.

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Hokkaido is dominated by various kinds of volcanic ash such as pumice flow and vitric tuff which are similar to shirasu in the southern Kyushu. Some characteristics of these raw materials and samples prepared by sieving, were investigated. The bloated particles were tried to be produced from these samples by heat treatment, their physical properties were measured and roughly estimated from the characteristics of raw materials. All the samples prepared could be used as raw materials of the bloated particles.
The results obtained are summerized:
(1) Because of high yield and good properties of the bloated particles, the following volcanic ash were useful as a good raw material of the bloated particles; two kinds of pumice flow in Minami-ku Sapporo-shi and Suenaga Date-shi, and two kinds of vitric tuff in Ikeda-machi and Makubetsu-machi Nakagawa-gun.
(2) The values of the expanding ratio and the yield of the bloated particles have some correlations with the physical properties of raw material, such as the values of the bulk density, the apparent density, volcanic glass content and weight loss of 600°C to 1000°C on thermal gravity at 20°C/min of the samples prepared, and could be estimated by the linear equation calculated by least square method.
(3) The values of the bulk density, the apparent density and hydrostatic strength of the bloated particles could also be presumed by the physical properties of raw material mentioned above.

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This paper presents a theoretical approach to the problem of heat and moisture pick-up of ventilation airalong wet roadways.
Firstly, the variation of temperature and humidity of ventilation air with distance along a uniformly wetroadway is analysed for different degrees of wetness; the wetness being expressed by a wetness fraction (f). Theresults show that the variation of both temperature and humidity are remarkably influenced by the degree of wetness. Under somecondition, it is possible that the air temperature (dry-bulb temperature) decreases with distance, whereas the relativehumidity increases.
Secondly, variation of the temperature and humidity along a partially wet roadway is calculated and thetemperature profile in the rock around the roadway is presented. By using a newly introduced value e and the resultsfor the uniformly wet roadway, a new method is proposed for calculating the temperature and humidity for a partially wet roadway.

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For the practical application of the vertical double-belt conveyor, it is most important to know how highit can convey material and how wide the belts must be. In this investigation, the maximum tension of the belts withvarious width is calculated based on the theory of similarity and the experimental data reported previously. The comparison of thecalculated values with the permissible belt tension makes it possible to determine the maximum height of conveyance for each beltwidth.
The main results are as follows;
1) For the same belt width, the maximum height of conveyance decreases with the increase of the sectionalarea of the load.
2) For the same belt width, the maximum height of conveyance is smaller for sand conveyance than for coal.
3) For the same height of conveyance, a smaller amount of conveyance permits the use of a little narrowerbelt, but not much.
4) The vertical double-belt conveyor can be applied more advantageously to the conveyance with a largeamount and small height than to the conveyance with a small amount and large height.

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For relieving the congestion of freight traffic, new transportation systems have been developed and proposed. The pneumatic capsule pipeline is one of the most promising systems
The leak factor and the coefficient of the rolling resistance of capsules are the characteristics of major importance in designing the pneumatic capsule pipeline system.
The experimental investigations were carried out on these characteristics by using 300mm and lm diameter test piepline. The results obtained are shown below.
1) The leak factor Ii defined as eq.(2) can be calculated as follows.
Ψ=1/2 (1/k²-1)(1)
k²the seal/pipe area
(2)
u: mean velocity of air flow, ν: capsule velocity, ρ: density of air,
Δρ: pressure dropinduced by capsule
2) The leak factor does not depend on the eccentric setting of the seal plates and Reynolds number within a range of practical apPlication.
3) The coefficient of rolling resistance is mainly affected by the error on setting wheels of the capsule.

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On wettability between formed coal powder and water, the measuring method has been developed by the present writer. In this report, the relation, between the wettability by above-mentioned method and the pelletizing property by Oil Agglomeration method, has been made clear, as in the following formula.
(D/C) ² ∝ log B (1+sin θ)
where, θ: contact angle
B: the product between specific surface area of raw coal and pure coal percent of that
C: mean diameter of raw coal (on R-R-B size distribution co-ordinate system)
D: mean size of O. A. pellets
The apparatus of the above-mentioned O. A. method is shown in Fig. 1 and Fig. 2.

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Capillary potentials of granular beds were determined by two methods, measuring the equilibrium height of capillary rise into a vertical sample column and measuring the pressure necessary to force air through liquid saturated particle beds. Granular materials used were glass beads, abrasive fused alumina and sand.
From analogous definition of the hydraulic radius for the particle beds. It follows that for the equilibrium height h_f or entry pressure Pe,
pgh_f=Pe=6 (1-_e)γcos θ/(e ds)
Where ds is the specific surface diameter, e the void fraction, g the acceleration of gravity, γ the surface tension of liquid, θ the contact angle, p the density of liquid.
This equation was derived from energy change accompanying capillary rise of liquid.(Minimization of the potential energy due to the force of grabity and the surface tention.)
Experimental results for the sample materials was substantiated by the equation with ds obtained by a permeability method. The values of constant in the equation were estimated to be 5 from the height of rise measurements and 6 from entry pressure measurement. It should be emphasized that granular beds showed a large capillary hysteresis.

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To prepare high-purity vanadium metal, the investigation of deoxidation and decarburization of a crude vanadium containing a small amount of carbon and oxygen, obtained by the carbothermic reduction of vanadium oxide, was made by an A_r-H₂ (5-25 vol.%) plasma arc smelting.
The results obtained are as follows:
1) Carbon and oxygen contents in a crude vanadium obtained by the carbothermic reduction of vanadium oxide were dependent, and controlled on the mixing ratio C/V₂O₅.
2) Remarkable deoxidation from a crude vanadium was found in the A_r-H₂ plasma arc smelting, but decarburization was insufficient, as expected by the thermodynamical calculations.
3) Massive vanadium metal of about 99.6% purity, with a hardness of Hv=180, was obtained by the A_r-H₂ (25 vol.%) plasma arc treatment of a crude vanadium with high oxygen and low carbon content.
4) Deoxidation reaction was mainly due to the reaction between oxygen in vanadium and hydrogen molecule and/or atom at high-temperature, and the contribution of metal suboxide volatilization to deoxidation was small so that loss of vanadium was reduced. Therefore over all metal yields of above 85% were typical.

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One of the most injurious among impurities in soft solder is antimony originating from lead recovered frombattery scraps. As soft solder contains tin which is easy to be oxidised, removal of antimony by the preferentialoxidation is not applicable to the soft solder unlike the case of lead.
In this study the property of antimony to form with magnesium an intermetallic compound, Mg₃ Sb₂, wasutilized in removing antimony from molten soft solder. As the compound has a high melting point of 1228° and lowdensity of 1.33g/cm³, when large crystals of the compound were formed, they gathered by buoyant force near the top ofthe molten soft solder and most of antimony could be removed from the bulk.
A sample composed of Sb-containing soft solder and magnesium was melted and kept for lh at 900° in an evacuated quartz ampoule, then cooled at a slow cooling rate down to a set holding temperature. It was again keptfor 1h at the holding temperature and quenched in water for observation of the distribution of the crystals and for analysis ofresidual antimony and magnesium.
A slow cooling rate and a low holding temperature are necessary for the growth of the crystals. At aholding temperature of 350° and by addition of as much wt%Mg as the initial wt%Sb in soft solder can lower the residualantimony to less than 0.01wt%. The solubility relation can be represented by log[%Mg]₃[%Sb]₂=11.8-11400/T

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The oxidation of ilmenite are prior to selective chlorination is of commercial importance. The rate ofoxidation was investigated employing a thermobalance and boat weighing test. It is mainly influenced by three factors-temperature, partial pressure of oxygen and particle diameter. These factors were selected as follows:
T=800-1000°, P_O2=0.004-1.0 atm, d_p=74-297 microns.
The oxidation products were found to be different over various temperature ranges and partial pressures of oxygen. Results were showed as follows:
800-930°: Hematite, Rutile, Pseudobrookite above 930°: Rutile, Pseudobrookite
The oxidation kinetics was the pore-blocking model at the initial stage followed by the parabolic ratelaw. The activation energies associated with the parabolic rate law was 11.9 Kcal/mol in the high temperature range and 31.9Kcal/mol in the low temperature range. The kinetics of oxidation in the fluidized bed reactor was also the parabolic rate lawin the low temperature range which was independent of the partial pressure of oxygen.

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