Fukasawa Mine is a kuroko mine, developed and operated with a fully trackless sytem. The cut and fill method with artificial roofing is applied; about 20 drift headings spread throughout an area of 2.0km by 1.0km and are generally being worked on to produce 26, 500t of crude are per month. These drift driving works progress in cycles of drilling and blasting, mucking, and timber supporting.
The development of Mine On-Line System (MOS) is composed of innovations on mining machines and underground communication; it aims to establish the optimum combination of workers, machines, and drift headings. Innovations in mining machines include the development of cross-cut jumbos, timbering machines, and scale-up of loaders. An innovation in underground communication is the adoption of the integrated underground communication system combined with a personal computer.
A drastic improvement of worker's performance has already been observed and further improvement is expected.
The mine production is scheduled to increase to 30, 000t per month in the near future, due essentially to the improvement of productivity as a result of the MOS project.

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Since 1980, improvements in the entire process of copper smelting and refining at Saganoseki Smelter and Refinery have been effected to reinforce its competitiveness as a custom smelter.
I. About 10 percent reduction in the total operation cost has been achieved due mainly to lowered energy consumption:
(1) Energy cost was considerably reduced by completely switching fuel for flash furnace from C heavy oil to powdered coke and by constructing low electricity consuming type of converter for acid plant.
(2) In order to improve smelting capacity of flash furnaces and converters without adding extra facilities, matte grade was raised from previous 60% to 62% by means of higher concentration of oxygen in the blast only with a construction of an additional oxygen plant (3, 700 Nm3/H). Thus, an increase in the concentrate treatment capacity and higher matte grade were made possible, thereby increasing copper.smelting capacity by 25% to 300, 000 tonnes in copper content per annum.
(3) A new efficient tank house equipped with a special double-hook loading system was built, replacing both No.1 tank house at Saganoseki and No.1 tank house at Hitachi.
(4) A set of belt conveyors covered by large steel pipes was extended to link the conveyor network right from the wharf to storage facilities, etc. to rationalize the transportation system for receiving concentrates and nickel ores. It also serves for shipment of slag. This sytem not only entirely replaced truck haulage but also effectively eliminated handling loss and environmental pollution.
II. Complexed copper concentrates treating capability has been increased:
(1) To separate and recover such impurity elements as Pb, Zn, As, Bi, etc., a new plant for processing Hot Cottrell converter dust was constructed.
(2) Both electrolyte purification capacity of the tank house and arsenic separation and recovery capacity of the acid plant were increased.

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This paper discusses the stability of a large rock slope at the time when seismic wave is propagated to such structure.
To examine the dynamic stability of the large slope by adopting modal analysis, we propose the technique how to calculate the vibration modes of the model by finite element method, how to calculate a maximum amplitude of every node in the model from above vibration modes, how to obtain the local safety factors by using the combined displacements to superpose the static displacements and the amplitudes, and how to estimate the dynamic stability by the distribution of the safety factors.
In this paper, a theoretical analysis of dynamic response of the rock structure, definition of local safety factor, adoption of our attempt to process a dynamic system, and the simulation to estimate the dynamic stability are discussed.
The result of this simulation shows that the stability is affected unfavorably with decrease in the order of vibration modes, and that partial sliding may occur near the toe in a large rock slope during severe earthquake of its intensity 6, and gives other various suggestions for future study.

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In this research, the coal fracturing activity due to advance boring was observed by the acoustic emission methods in order to obtain the informations for judging the hazard of coal and gas outburst.
Practically, one-dimensional source location were conducted from acoustic emission signals detected in the stress relief boring for coal seam. Furthermore the amount of cuttings in addition to acoustic emission activity was measured at every unit drilled length in that boring and the shield boring designed specially to prevent the collapse of a borehole. The fracture criterion of the coal seam saturated with gas under high pressure was analyzed to explain the characteristics of the acoustic emission activity in advance boring. The main concluding remarks are as follows:
1) In many cases the acoustic emissions due to fractures of coal seam occurred near the cutting points and in some cases at a distance ahead from the region of the stress concentration associated with the bottom of a borehole.
2) In the former cases the amount of cuttings increases and decreases almost without retard of the acoustic emission activity, while in the latte r cases in some retard.
3) The retard of the discharge of cuttings from the acoustic emission activity is considered to be an useful information for judging the hazard of coal and gas outburst because this retard is due to the local coal fractures which are caused by the change in gas pressure in coal seam at a distance ahead from the bottom of a borehole.

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This paper presents an experimental investigation of an axial developing process of bubble and slug flow patterns for airwater mixtures upward flowing. The experiments were carried out in a transparent aclylic plastic pipe of 39.6 mm diameter and 5.66 m length. To investigate the effect of inlet conditions on the flow characteristics four air injectors were used and void properties such as bubble transit frequency, void fraction, bubble transit length and bubble velocity were measured by electrical resistivity probe technique up to the axial position of 100 pipe diameters from the air injector. Also axial pressure distributions were measured.
The results are as follows: It is difficult to examine the entrance region by the pressure gradient in bubble and slug flow patterns because the static pressure changes monotonously. In the flow conditions of transition from bubble to slug flow patterns the flow properties of entrance region depend on inlet conditions. In the case of slug formation at just near air injectors the developing process is independent of inlet conditions and the flows develop at the axial position of 80 to 100 pipe diameters.

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The size reduction of waste polymer and composite materials has become an important subject in the field of waste reclamation. And then energy consumptions by size reduction of waste polymers are very large for the reason of their high strength.
Therefore, using a shredder-type crusher having fixed and rotary cutting blades, the effects of clearance between cutting and fixed blades, open size of screen and pulverizing resistance on the pulverizing efficiency and rate have been investigated experimentally for 2 kinds of GFRP.
The results obtained are as follows:
(1) Pulverizing efficiency η increased with decreasing clearance C and increasing open size of screen D.
(2) Pulverizing efficiency η decreased with increasing pulverizing resistance F₁, for D=6-4mm, this F₁ was in proportion to ILSS (Interlaminer shear strength), but for D=12-8mm, inversely as that.
(3) Pulverizing efficiency η and rate constant K₁ are shown next eq.(a)-(b).
ln (l-η) =-K1·T+K₀.(a)
K₁=-D^m1/C^m2·F₁.(b)
m1=1.25-1.71, m2=2.09-2.36
K₀: constant
(4) Pulverizing rate constant K₁ for GFRPs are smaller than that for resins.

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The adsorption behavior of heavy metal ions such as Cu, Pb, Zn, Cd, Co, and Ni, which exist as a cation, and arsenous acid on deep sea manganese nodules, were studied for the recovery of the metal ions contained in waste waters from the mines. It was observed that heavy metal ions were well adsorbed on the nodules at moderately low pH, provided the reaction is given sufficient time, though the adsorption of arsenous acid is low. The order of activities of the ions for adsorption was: Pb>Cu, Cd>Zn>Ni>Co>>As. The chemical compositions and mineral compositions of the nodules show scarecely effects on the adsorption of heavy metal ions. However, the nodule which is relatively rich in Fe and Co, adsorbs larger amount of As than that which is more abundant in Mn, Ni, and Cu and is composedof 10 Å manganite.

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Flotation experiments of fine particles (-10μm) of quartz and hematite were carried out as a function of pH using mono-, di-, and triamine acetates as collectors by Denver-type laboratory flotator. Amines used were dodecyl amine (C12H25NH2), dodecylpropylene diamine (C₁₂H₂₅NH (CH2) 3NH2), and dodecyldipropylene triamine (C12H25NH (CH2) 3NH (CH₂) ₃NH₂), respectively. Dissociation constants of diamine and triamine were determined by pH titration according to the Schwarzenbach's method. Reverse flotation of quartz from an artificial mixture (1: 1 by weight) with hematite was also carried out by varying the collector concentration in both acidic and alkaline media.
1) As dissociation constants, pK_α1 10.2 and pKa2 11.3 for diamine, and pK_α1 9.0, pK_α2 10.1, and pK_α3 11.3 for triamine were obtained, respectively.
2) Individual flotation tests showed that, in acidic media, flotation recovery of quartz increased with the increase of the number of amino radical of collectors, while no appreciable difference in flotation recovery of hematite was indicated. In alkaline media, flotation recoveries of quartz were enhanced with diamine and triamine, and floatability of hematite increased with increasing the number of amino radical of collectors.
This flotation behavior was explained by an electrostatic interaction between surface charges of minerals and positive charges of collectors resulting from their dissociation.
3) Reverse flotation of quartz from an artificial mixture was impossible in acidic media (pH=5) because of heterocoagulation of quartz and hematite.
Better results of reverse flotation were obtained in alkaline media (pH=10) using diamine and triamine in comparison with those using monoamine.
Reverse flotation tests at pH=10 and at a collector concentration of 5×10^-5M showed that the flotation rate of quartz increased while that of hematite decreased with increasing the number of amino radical of collectors.

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As reported earlier, a new-type lead dioxide electrode was developed by the authors. A few of the outstanding charac-t eristics are durability, high resistance to chemical action, and high electric conductivity. The method of preparation consists in electroplating silver on expanded titanium mesh used as a substrate, then applying by electrodeposition a residual-stress-free coating of α-PbO₂, and finally a coating of β-PbO₂.
In the present work, scaling-up experiments were carried out with a view to obtaining technical information necessary for the production of the newly developed electrodes in sizes greater than the commercial electrodes. The results indicate that such electrodes can be produced under conditions determinedfrom the data obtained in the laboratory-scale work.

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In the present study, the following three kinds of concentration cell were constructed and equilibrium e.m.f. were measured in the temperature range of 873-1173 K (Cell I, II) or 873-1373 K (Cell III).
Pt, SO₂, SO₃, O₂/Na₂SO₄/SO₂'SO₃', O₂', Pt.cell I
Pt, SO₂, SO₃, O₂/Na₂SO₄/β-Al₂O₃/Na₂SO₄/SO₂', SO₃', O₂', Pt.cell II
Pt, SO₂, SO₃, O₂</β-Al₂O₃, /SO₂', SO₃', O₂', Pt.cell III
In every cell, the left hand electrode, that is the reference electrode, was composed of 9020 or 9470 ppm SO2 and balanced by air and right hand electrode, that is sample electrode, was composed of air containing many kinds of SO2 content.
From the experimental results the following facts were confirmed.
Provided that the Na₂SO₄ solid electrolyte pellet was made under the enough pressure, the stable and reliable e. m. f. values were measured and those found to be in agreement with the theoretical values calculated based on the thermodynamic values under the condition even if the ratio of PS0₂ (sample)/PS0₂ (reference) is 1/100.
However the construction of tube consisted of Na2SO4 is very difficult and we tried the use of β-Al₂0₃ tube replaced with Na₂SO₄ pellet as a solid electrolyte. In the experiment by using cell II, 5-10 mV higher values than the theoretical were measured and those values were stable and good reproducibility. Furthermore the response to the change of SO₂ content in air was as good as cell I. In the experiment by using cell III, the stable and good reproducible e.m.f. values were measured and those were in good agreement with the theoretical values.
ere in good agreement with the theoretical values. The response to the change of SO₂ content was a little worse than cell-I or II. However it could be concluded that the β-Al₂O₃ was proposed the very appropriate solid electrolyte for commercial SO₂ sensor which will be developed in near future.

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The extraction, stripping and separation of V from another metal ions with Alamine 336 and Aliquat 336 in kerosene were chiefly studied and these characteristics were clarified. Extraction of V from 0.01M vanadium sulphate solutions at about pH 3 with 0.01M Alamine 336 and at pH 2.5-8.5 with 0.01M Aliquat 336 were about 100%. The shaking times required for the extraction were about 20 min. with Alamine 336 and about 30 sec. with Aliquat 336.
The species that take part in the reaction were mainly H₂V₁₀O^4-₂₈ with Alamine 336 and H₂V₁₀O^4-₂₈, HV₁₀O^5-₂₈, V₁₀O^6-₂₈, V₄O^4-₁₂ with Aliquat 336. Stripping of V from Alamine 336 and Aliquat 336 were about 100% more than pH 8.8 with 0.1M (NH₄) ₂S0₄ solution and about 95% at pH 7 with 1M NH₄NO₃ solution, respectively.
Separation of V from the solution containing Fe²⁺, Cu²⁺, Ni²⁺, Mo (VI) and W (VI) were possible by the selection of optimum pH.

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