This paper shows how the laser holography was applied to obtain more accurate Poisson's ratio and Young's modulus of rocks from the determination of displacements in pure bending of prismatical thin rock bars. The small displacements can be recorded on a photographic dry plate easily and directly.
Poisson's ratio is calculated by taking the angle of two asymptotes of the hyperbolas i. s. contour lines expressing same displacement on the dry plate, and Young's modulus can be calculated by using the fringe's number of the hyperbolas in the specific distance in the bending direction. At the same time, these constants were also measured by a strain gage on which was sticked same sample.
As the results, Poisson's ratio and Young's modulus have a tendency to slightly decrease according to the increase of stress, and the values of which were obtained by the holography method were small and accurate to some extent as compared with the values by the strain gage method.

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This paper described about the drag reduction effect of injecting the solution of polyethylene oxide (PEO) through avpipe-wall slot injector set up in the upper stream of test section of a horizontal pipeline, transporting water or water-sand mixture; the test section is a polyvinyl chloride clear smooth pipe 7.0m long and 2.5cm of internal diameter.
The maximum drag reduction in the flow of dilute water-polymer solution made up by injection is observed larger than the one of the like solution made up before hand in a head-tank.
As for sands the authors used Toyoura sand, Chikugogawa medium sand and Chikugogawa coarse sand, the average particle diameters of these sands are 0.207mm, 0.62mm and 1.29mm respectively.
The relative hydraulic gradient reduction in the pipe flow of sand-water-PEO mixture ranges from 35% to 70%, where the volumetric. concentrations of sands 5% to 20%, the average velocities 3.0m/sec to 5.5 m/sec, and the concentrations of PEO in aqueous solution 40 ppm to 60 ppm that seems to bring about the saturation of the Toms' effect.
The head loss for the pipe flow of sand-water mixture injected PEO solution might be expressed as follows:
_??_I_WSP=head loss in unit length of horizontal pipe, sand-water-PEO d mixture, I_WP=head loss in unit length of pipe, PEO solution only, C_V=volumetric concentration of sand, U_M=mean velocity in pipe, C_D=drag coefficient of sand in dilute water-PEO solution given by settling test of sand, S=specific gravity of sand.

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The calibration method, derived from the theoretical equations, for flotation pulp has been examined using a batch, and an on-stream (closed circuit) x-ray analyser concerning the effects of co-existent elements, pulp density and particle size. According to this method, the size effect was corrected considerably even for size distributed samples.
As the applicable range of this equation to an ore grade and a pulp density was wider than a regression method, it was possible to analyse both feed pulp and concentration pulp with the same coefficients.
The results of this investigation showed that an accuracy of this method was lower than a multiple regression method using specific coefficients for each pulp, however, necessary amount of chemical analysis and calculation in order to determine the coefficients of this method should be reduced remarkably.

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This paper describes the results of preliminary experiment of recovering gallium from sodium aluminate solution, which is used for alumina production in Bayer Process and contains gallate as a minor soluble impurity.
The constant current electrolysis of concentrated caustic or caustic aluminate solution containing no impurities other than a small amount of gallate (0.2g/l as gallium oxide) was carried out in a small glass cell at various temperatures using a cathode of copper plate and an anode of nickel wire or stainless steel plate. The effects of cathodic current density, temperature and alkalinity of the solution on current efficiency of gallium deposition were investigated.
A maximum current efficiency was obtained at a current density of nearly 0.004 A/cm². Such result can be explained, considering the difference between partial polarization curves of hydrogen evolution and gallium deposition. The current efficiency reached about 18% in the electrolysis of 4N caustic solution at 30°C. The fact that gallium was deposited at this temperature, just equivalent to the melting point of gallium, suggests the close relation between the current efficiency and wetting ability of gallium to the cathode.
The increase of dissolution rate of gallium into the caustic solution with the increase of temperature and alkalinity has also a bad effect on the recovery of gallium, so that, decreases current efficiency.
It was estimated, from the analysis of the potential-current curve of the solution obtained by the potential sweep method, that the hydrogen over voltage for gallium cathode is larger than that for copper or platinum cathode and that the current efficiency can be raised by keeping the cathodic potential at a suitable constant value.

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The equilibrium distribution of bismuth in the liquid Pb and PbO-Si0₂ system was investigated by using the EMF method. The oxygen pressure in an equilibrium state was determined from e. m. f. of the following cell:
Ni-NiO/ZrO₂ (+OaO)/Slag-Metal-Gas System.
Slag composition ranged in N_pbo/ N_SiO2 from 1.35 to 1.86, and atomic fraction of bismuth in metal ranged from 0.03 to 0.12. Equilibrium temperature was 900°C.
The experimental results show that bismuth solubility in the slag increased with the increase of bismuth content in metal and PbO content in slag. The distribution coefficients of bismuth defined as wt% in slag/wt% in metal were or the order of 10^-3. These data were associated with the measured oxygen pressures and it was found that, if the activity of bismuth in metal was kept constant, the solubility of bismuth in slag increased in proportion to P_o2^3/4This result shows that bismuth in such slag exists as trivalent ion. Based on the experimental results and available thermochemical data, the activity of Bi₂O₃ and BiO_1.5 in the molten Pb-Bi-Si-O system were calculated. The activity of Bi₂O₃ was found to have a considerably negative deviation from Raoult's law and not to obey Henry's law even in such a dilute solution, while the activity of BiO_1.5 nearly obeyed the Henry's law and the deviation from Raoult's law was only a little. These results show that bismuth in such slag exists as mono-nuclear trivalent ion. The activity coefficient of BiO_1.5 was 1.6-2.2 and increased a little with the increase in SiO₂ content.

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