In the previous study the author pointed that there were many problems about practical blasting theory in Japan.
Experiments were performed to establish the relationship between blasting factor and blasting effect (funnel ratio N).
The material used for blasting (crater test) is a cubic mortar block, (60cm × 60cm × 60cm), the four vertical faces of which were utilized. The total number of the experiment is 110.
The results are summerized as follows:
The funnel ratio ranges between 2.5 to 4.5 in proportion to the rock strength and the burden. It was also noted that the funnel ratio is independent of the explosive amount.

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The degree of cracks in rock mass can be evaluated by using RQD, because the value of RQD generally decreases as the number of cracks increases. It is well known that P wave velocity decreases with the existence of cracks and faults in rock mass. Sugimoto (1979) studied the relation between RQD and P wave velocity by using the data from in situ measurement.
In this study, the relation between RQD and P wave velocity is investigated by means of numerical simulation. A synthetic seismogram of a transmitted P wave is simulated by using the communication matrix method, and the P wave velocity is obtained from the seismogram with considering actual measuring conditions. The results are as follows.(1) The P wave velocity linearly decreases as the RQD decreases.(2) Their relation varies according to the property of rock.(3) The measured P wave velocity is not equal to the time average velocity.

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Cone-and-plate viscometers are suitable and popular devices for measuring non-Newtonian fluid flow characteristics because the shear rate of fluids in the gap between the cone and the plate is constant and they are easy to operate and commercially available. In this paper, a theoritical analysis of the cone-and-plate viscometerfor a Casson model fluid and a Herschel-Bulkley model fluid is presented.
Since the theoritical equations derived are complicated, especially for Herschel-Bulkley model fluid, the first and second approximate expressions of the equations are derived. It is found through the comparison between the theoritically calculated values and the approximates that the first approximate expression is unsuitable for the calculation in the case that the included angle between the cone and the plate is over 2° to keep the relative error between the theoritical values and the approximate ones under 1%.
Moreover, it is confirmed that the second approximate expression is applicable to the calculation in the case that the included angle is up to 4° under the condition in which the relative error is less than 1%.

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Various types of TBM are now available, and widely used as a substitution for the conventional tunneling method, namely drilling, blasting, and mucking. Potentially, TBM performance is far beyond the conventional method and if TBM is properly applied and used, mean penetration rate may be several times greater than that of conventional method. However, in some occasions TBM shows very poor performance if it is used in the adverse condition to TBM. Therefore, it is very important to discuss the applicability of TBM and develop the system to evaluate the performance of TBM in advance.
In this paper, knowledge concerning to TBM performances is collected and implemented in a computer program which can be called an expert system for applicability of TBM. The program consists of three part;
a. Check the fundamental requirements whether fulfilled or not,
b. Estimate the operational conditions for the site,
c. Check the proposed conditions from the various points.
The second part may be a tiny expert system and makes the several proposals for the final part. In part c., the knowledge of many authors or experts are implemented and the proposed conditions are evaluated.
In this expert system, input parameters are tunnel length, tunnel diameter, maximum curvature, dip, uniaxial compressive strength etc., and penetration rate, normal force, rolling force etc. are deduced together with the appraisal and recommendation for users. Through the several case studies, it was found that the developed expert system gives the appropriate results especially for the tunnels excavated in North America and Europe. In cases of tunnels excavated in Japan, the estimated penetration rate is far less than the actual result. Consideration for complicated environments and surroundings differing from country to country may be remained for future.

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The solvent extraction-spectrophotometric determination of aliphatic amines was developed using metanil yellow (MY) as an ion associating reagent. Dihexylammonium ion (DHAH⁺), trihexylammonium ion (THAH⁺) and monododecylammonium ion (MDAH⁺) form the stable ion associates with metanil yellow ion, which are extracted into chloroform. These ion associates give the absorption maximums at a wavelength of 402-407nm. The absorbance is little influenced by the existence of inorganic divalent cations other than Ba²⁺ ions. The molar absorptivities of these ion associates were as high as 2.48×10⁴ 2.62 × 10⁴ 1 mol^-1 cm^-1.
It is considered that the capillary condensation of neutral molecules between the contact points of the particles take place in alkaline media in addition to normal adsorption of ionic and molecular species. This effect becomes remarkable with decrease of the particle size

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The effect of sericite property on clay flotation of Amakusa pottery stones with Coco amine hydrochloride (COAC) as a collector was examined for the samples collected from different quarries. The clay minerals of Amakusa pottery stones are mainly sericite and a little amount of kaolinite. Results obtained are summarized as follows.
1) When sericite in Amakusa pottery stones was treated with dodecylamine hydrochloride (DAC) which is the main component of the collector, dodecylamine-sericite complex was formed in the interlayers of sericite. The formation ratio of dodecylamine-sericite complex increased with the increase of the ratio of swelling layers (montmorillonite) in sericite.
2) The flotation recovery of clay minerals was low, since the amount of COAC adsorption on the external surface of clay minerals was little due to the large amount of COAC adsorption in the interlayers of sericite with the swelling layers.
3) With increasing the ratio of the swelling layers in sericite, the amount of DAC adsorption increased and the flotation recovery of clay minerals decreased.

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The activity coefficients of a solute at infinite dilution in 23 copper solutions have been estimated by applying a recently developed theoretical equation for metallic solutions. Good agreement between the calculated and experimental values was found with over 90% reliability in the prediction of the correct sign. The agreement between the absolute values is also reasonable, considering that only fundamental physical quantities (hard sphere diameter, atomic volume and Miedema's molar heat of solution at infinite dilution of the constituent elements) are employed for computation. The interaction parameters of hydrogen, sulphur and oxygen in 75 ternary copper solutions, have also been calculated in a similar manner to the case of the solute activity. Moderately good agreement was observed between the calculated and the available measured values of 44 cases. Better agreement was obtained when the molar heat of solu tion of oxygen at infinite dilution calculated from Fitzner's semi-empirical equation was used rather than Miedema's estimation which may not be as sufficiently effective when applied to a non-metallic element.

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