In the previous report, the authors discussed theoretically the relationships between the stress rate and the inelastic volumetric strain rate, and also the strength of rocks.Now we tried to improve the uniaxial compression testing arrangement, and then attempted to verify experimentally the equations in the previous report and to evaluate the several parameters.
Granodiorite was selected for this study because it is very compact and consists of alkali-silicate minerals.The specimen's configuration was circ lar cylinder whose length/diameter ratio was about 2.6 according to the suggestion by Mogi. The platens used were ghtly larger than the specimen in diameter to reduce the clamping effect.After the loading conditions were checked numericali, and experimentally, specimens were subjected to the uniaxial compression at constant deformation rates at which the strength measurements are usually performed.
The results obtained are as follows:
(1) The clamping effect near the ends of the specimen is reduced and the uniform stress field extends remarkably under the loading -condition used in this study.
(2) The inelastic volumetric strain rate, dε_vi/dt, is expressed as a function of stress, σ, and stress rate, σ, namely Vε_vi/Vt=A₄σ^2m-3 (l-m/l-1)·l-m/σl-1
An exception, however, exists in the region above 80-85% of the fracture strength, where the inelastic volumetric strain rate accelerates.
(3) The strength, DMax, is related to the stress rate by logσ_max=1/b+1 logσ+A₅ where A4 and A are constants.
(4) The indirect measurement developed in the previous report suggests that the parameters b and m are 32±2 and 2.57±0.06, respectively.

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The thermochemical properties of gases in the combustion chamber are the most significant for designing the nozzle configuration of the jet burner and for calculating the thermal characteristics of impinging jet flame.
The thermochemical calculation of air-kerosene jet burner is more troublesome than that of oxygen-kerosene jet burner due to the existence of nitrogen component. The authors carried out the thermochemical calculation of air-kerosene jet burner with an easy method. With this method an equation of fourth degree was devided into two quadratic equations by introducing two initial values. The solutions which satisfied chemical reaction, chemical equilibrium, energy conservation and total pressure were obtained.
The deduced nozzle exit temperature from the calculated combustion chamber temperature closely coincided with the measured flame jet temperature.
The following physical properties are reported:
A. relations between air-fuel ratio and (1) combustion chamber temperature (2) specific heat ratio (3) gas constant (4) partial pressures of gases (5) weight precent of toxic gases
B. relations between heat loss and (1) combustion chamber temperature (2) partial pressures of gases (3) weight percent of toxic gases

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In this paper the author investigated the effect of specific surface, distribution modulus and size modulus of pulverized fines on the crushing strength of green compacts made from fines of pulverized silica sand, aiundum, lime stone and two kinds of calcites.
The results obtained are summerized as follows;
(1) In case of sized fines the relation between the crushing strength of green compacts and specific surface of fines measured by the air permeability method was expressed by a straight line.
(2) It was recognized that the crushing strength of green compacts made from fines contained the wide size distribution increased with increase of specific surface, but could not be evaluated by the specific surface alone, and in spite of the same specific surface, the crushing strength varied with changes of size distribution.
(3) It was recognized that decrease of distribution modulus and size modulus of pulverized fines which follow the G-S size distribution formula increased the crushing strength.
(4) It was recognized that the relation between the crushing strength and distribution modulus was shown by a hyperbolic line.
(5) It was recognized that the relation between the crushing strength and the reciprocal of size modulus was shown by a straight line.

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Following the preceding report, the miscibility gap and the distribution of silver between molten lead and speiss in the Pb-Cu-As ternary system and the Pb-Fe-Cu-As quarternary system have been determined at 1200°C.
The accuracy of the quenching method was confirmed by the fact that the miscibility gaps determined by direct sampling from the equilibrated phases under an inert atmosphere agreed well with those determined by the quenching method.
In the Pb-Cu-As system, a rather wide miscibility gap was observed at 1200°C, in spite of the fact that no miscibility gap was found in the Pb-Cu binary system. The shape was almost the same as those determined at 1000°C in a prior study
For the Pb-Fe-Cu-As system, the compositions of speiss were established in the range between the two ternary systems, Pb-Fe-As and Pb-Cu-As, and presented on a pseudo-ternary phase diagram. The compositions of speiss were strongly affected by the ratio of copper and iron in speiss while the compositions of metallic lead were found on the same line as that for the Pb-Cu-As system.
The distribution coefficient of silver between speiss and metallic lead, KAg, for the Pb-Cu-As system at 1200°C was approximately 1.2 over a wide range of arsenic content in speiss and was independent of temperature.
Distribution coefficients for the quarternary system were determined and were distributed between the values for the two ternary systems.
The values of KAg increased with increasing copper-iron ratio-and arsenic content in speiss.
The distribution coefficients of silver calculated from practical data agreed well with the present results.
From this study, it was concluded that the copper-iron ratio in speiss should be kept as low as possible in operations to concentrate arsenic in speiss.

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The reduction of tantalum pentoxide by carbon has been investigated in an argon plasma-arc furnace. Briquettes of tantalum pentoxide and carbon mixtures were reacted at about 3100°C above the tantalum melting point. The results were as follows:
1) The optimum mixing ratio of carbon and tantalum oxide, C/Ta₂O₅, is in the region of 5.10 to 5.15 and is somewhat larger than the stoichiometric ratio of 5. When the mixing ratio is below this range, the oxygen remaining in the product increases, while the tantalum carbide, Ta₂ C, increases when the ratio is larger than 5.25.
2) The sample weighing 7g is fused within 60 to 70 seconds by plasma-arc heating and the reduction of tantalum oxide proceeds rapidly to approximately 99.5% Ta during this period. Subsequent reduction in the molten state is slow. Within 10 minutes, the maximum content of tantalum in the reduction product reaches 99.93-99.94% while the remaining oxygen and carbon are 50 ppm and 400-500 ppm respectively.
3) The hardness of the product with the highest tantalum content is about Hv 170 and is somewhat larger than that of pure tantalum metal due to the small amount of remaining carbon.
4) The presence of small, dendritic, primary crystals is observed in the reduction product high in tantalum content. In these crystals, small amounts of oxygen and carbon is considered to distribute uniformly in solid solution.
By plasma-arc heating, the carbon reduction of tantalum oxide proceeds rapidly. The remaining oxygen and carbon in the reduction product reach concentrations of about 50 ppm and 500 ppm respectively.
In order to decrease the content of carbon further, a suitable refining process is necessary. However, the reduction method examined in this study is considered to be an useful process for the production of lump tantalum metal.

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