This paper deals with methods and results of “in situ” measurements of the average heat transfer coefficient (α_m) and the local heat transfer coefficient (α_x) from mine airway surface to ventilating air, that were carried out in three galleries of Kashima Colliery of Joban Coal Mine.
α_m obtained in fully-developed flow regions in two galleries that were at different conditions and the estimated values from the formulas proposed by authors (Ref. 14) were in good agreement.
Further, α_x obtained at sixteen measuring points in both developed and undeveloped flow regions did not show the particular tendency against the location along the air flow and the periphery of the galleries. But arithmetic mean value of the α_x and value of the α_m in each gallery were of the same order.

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In this paper, it is described that the stress distributions will be calculated by using the complex stress function and conformal representation for an infinite plate, under any uniform edge force, containing an elliptical region filled with material having the modulus of elasticity (E_I) and Poisson's ratio (υ_I) which are different from those (E_M, υ_M) of the, plate.
The results show the distributed stresses have almost same values as the edge ones (O_y ∞, τ_xy ∞), excepted the limited region of the tip of elliptical inclusion.
And taking into consideration of stress concentration around an elliptical inclusion, the condition of rock fracture in principal stress co-ordinates is shown by straight line in the compressive stress region.
Also the experimental results used a sandstone are fitted with the theoretical calculation (υ_I/υ_M=0.6, E_I/E_M=0.1).

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For the purpose of studying the failure mechanism of rocks, tension and compression tests were conducted on sandstone, granite and marble with a system of stiff testing apparatus. Some of the results obtained are as follows:
(1) The Young's moduli for tension and compression seems to be nearly equal within each low stress range.
(2) The stress-strain curves under tension begin to incline downwards remarkably as the stress increases, while under compression, there is scarcely such a tendency. The stress-lateral strain curves under compression have also the same tendency.
(3) Under the tension and compression tests, acoustic emission (A. E.) occurs from comparatively low level to the half level of the maximum stress. Under compression tests, A. E. occurs continuously with high frequency during the extensive post-failure deformation.
(4) The deformation and failure behaviors under repeated tension tests seem similar to those under repeated compression tests, and the Kaiser's effect is noticed also under tension.

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The adsorption characteristics of heavy metal ions on the svnthetic zeolite which is reared from the preheated mixture of Shirasu volcanic ash and Na₂O have been investiated by a batch method.
From effects of pH on adsorption of Pb²⁺, Cd²⁺, Cu²⁺ and Zn²⁺ ions, it is found that the snthetic zeolite efficientiy adsorbs metal ions in solution above pH 5, but the adsorptive ability of the synthetic zeolite is sharply reduced in acidic solution below pH 4 because of the decomposition and dispersion of the synthetic zeolite.
Adsorption capacities of the synthetic zeolite (faujasite) are 5.05 meq/g for Pb²⁺, 3.70 me/g for Cd²⁺, 3.56 meq/g for cu²⁺ and 2.69 meq/g for Zn²⁺. These values are about ten times those of natural zeolite (mordenite).
The order of selectivity for adsorption of metal ions on the Synthetic zeolite is Pb²⁺>>Cd²⁺>Cu²⁺>Zn²⁺.
The adsorption isotherm of metal ions on the synthetic zeolite follows Langmuir's equation in the range of equilibrium Concentration from 8.0×10^-5 to 1.5×10^-2 mol/l at 25°C.
Adsorbed Cd²⁺ ion on synthetic zeolite can be eluted effectively by the treatment with NaCl solution above 0.17 mol/l.

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On the strict sense of the word, all actual partition curve of the jig separation is the curve of coal having some range of the size.
On the other hand, some difference of separating densities for the respective particle size will be indispensable.
Therefore, as the partition curve of the jig separation is consisted of many different curves for the different particle size, the overall partition curve will be deformed some extent.
Author has made some calculations for the prediction of the washing result basing on the conditions stated below.
(1) The falling times of the particle in jigging have decided at 0.15 seconds obtained from the experimental result of the commercial air pulsated jig.
(2) The value of I (Imperfection) has assumed as a function which is depending on the numbers of jigging for the each particle size.
Both partition curves obtained from the calculation and actual test were well coincided each other.
Author has the opinion that the reason of the deformation of the partition curve is influenced by not only due to the imperfectness of separation but also due to the difference of the separating density for the difference of the particle size.
For the correct prediction of the washing result, it will be very important to consider the difference of the separating densities for respective constitution of the feed coal.

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Two sets of operating conditions of the lead blast furnace were applied to the mathematical model ofthe _lead blast furnace proposed by the author. Longitudinal distribution of the process variables such as the temperature of gas, burdens, molten lead and molten slag, the fractional conversion of ore and coke, the volume flow rate of gas and burdens, the composition, density and pressure of gas, and the bulk density of burdens were computed numerically by a digital computer. Actual computation was conducted for the following three case.
1. Most simplified model in which the heat and mass transfer along with the reduction of lead oxide is taken into consideration.
2. 2nd model in which the rate of solution-loss reaction is added to the above most simplified model.
3. Full model in which the rates of burning of coke with O₂ gas and of the reaction between CO and O₂ are further added.
For each case, the computed results seem to be reasonable. Therefore, the mathematical model is thought to be useful for estimating the furnace condition. This means that the model can offer the fundamental information for the improvement of the operation.

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The dissolution of hydrogen gas in aqueous solutions was studied in connection with hydrogen reduction of metals from solutions. Dissolution rates as well as solubilities of hydrogen gas in various aqueous solutions were determined by a pressure transducer technique.The main results obtained are as follows:
(1) Initial dissolution rates of hydrogen gas in pure water increase linearly with the increase in hydrogen pressure.
(2) Hydrogen dissolution in aqueous solutions is accelerated by strong agitaion and high temperature, obeying an empirical formula, R=c exp (αω), in which R is the dissolution rate. c is the function of temperature.α is a constant and ω is the stirring speed.
(3) Activation energy for hydrogen dissolution in pure water was apparently found to be around 3 kcal/mol, and this suggests that gaseous hydrogen dissolves at a rate which is diffusion-controlled in water phase.
(4) The dissolution rates of hydrogen gas in aqueous solutions depend primarily on its solubilities which is decreasingly affected by the addition of solutes.

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