1.資源ナショナリズムの抬頭など世界の政治, 経済の変化により, 国際資源企業が中心になって, 資源開発のリスクをプールして, 成功した開発事業の利益で他の国での失敗したリスクの費用を補填することは不可能になった。
2.この打開策の1つとして国連天然資源探査回転基金などもリスクの別のプールの方法として活動を開始したが, 多くの発展途上国で必ずしも本心から受け入れられていない。
3.世界的視野で資源の安定供給を維持するためには, 確認埋蔵量と生産能力の維持, 平和と自由貿易が重要で, 長期契約などは二義的なものである。
4.国際資源企業でも, 国連回転基金などでも, リスクをプールして確認埋蔵量を増加させることが困難であり, 別のシステムを探査リスクのプールに導入する必要がある。
5.発展途上国援助の増額が要請されている我が国の場合, 輸入資源の利用で得た利益からの税収の一部を, 次世代の資源の確保のために, 発展途上国援助として, 開発にリサイクルするのが最も実現しやすい方法である。
6.上記の援助は相当な規模で行なわれるべきであり, その援助の実施主体, 成功の場合の開発の実施企業, 生産品の処分方法などについて, 探査, 企業化調査など援助の時点で条件をつけるべきでない。
7.先進資源保有工業国の企業人は天然資源産業に対する政府の関与に反対しているが, 発展途上国の探査事業に, 先進諸国の政府の関与は不可欠である。などとなろう。
日本鉱業会が, 資源・素材学会と名前を変えて, 装いも新たに出発をする時, 我々資源産業人も少し, 物の考え方を変え, 長期的, 地球的視野に立って, 資源政治学や, 資源経済学について勉強をして行く必要があると思う。本稿では筆者が常に考えていた新しい探査リスクのプール方法についての考え方を述べて見た。関係各位のご批判を賜れば幸いである。

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Reactions between some refractories and copper matte-fayalite slag melts were directly observed at 1473 K by high temperature X-ray radiophotograph technique for the purpose of testing the refractories for protecting tube to Cu-slag with molten copper or matte.
Local corrosion was clearly observed at the surface of slag and the interface between copper matte and slag in high grade alumina crucible. The mechanism of local corrosion was discussed from the viewpoint of viogrous movement of slag film at the interface due to the Marangoni effect. The results of measuring the surface tensions of Cu-slag and the interfacial tensions of copper matte-slag systems confirmed the mechanism by the Marangoni effect.
High grade magnesia refractory was found to be stronger for the corrosion by copper matte-slag melts. Visible local corrosion of magnesia was hardly observed in the melts, especially in the copper-slag melt even after 24 hours. A cermet consisting of alumina and chromium showed a stronger ability of protection than the magnesia refractory from attack of copper matte-slag melts.
Since violent generation of gas was found in the oxidation reactions of silicon nitride (Si₃N₄) and silicon carbide (SC) with Cu slag, both non-oxide type ceramics were considered to be insufficient to protect tube from Cu slag.

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The concentration of oxygen in liquid copper has been investigated by the solid-electrolyte galvanic cell Pt|Ni-NiO|ZrO₂+11mol% CaO|O(in Cu liq.) |Mo at 1473 K under high vacuum for the concentration range of oxygen down to less than 1 ppm. Alumina and graphite, are used as crucibles for melting of copper. CuO addition into liquid copper and subsequent hydrogen reduction of it are carried out in alumina crucible. Oxygen concentrations determined by analysis and calculation were compared with each other. Results are as follows:
(1) Oxycell probe used in this work generates stable e.m.f. under high vacuum as well as under atomospheric pressure.
(2) Calculated values from e.m.f. values show precise oxygen concentration in the liquid copper down to about 1 ppm.
(3) The oxygen concentration of less than 1 ppm can be measured in the melt with stirring.

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In this research, dissolution of the synthesized copper ferrite in aqueous sulphuric acid was investigated where temperatures were varied from 323 K to 343 K, sulphuric acid concentration from 1 M to 3 M and experiment was done using a rotating disc system Effects of Fe³⁺, Fe²⁺ and SO₄^2-were also studied. The experimental results have shown that, in the initial period of dissolution, rate of copper was greater than one of iron, leaving Fe₂0₃layer outside, and therefore, non stoichiometric dissolution of copper and iron. After long time of dissolution period, the stoichiometric dissolution of copper and iron was shown to be attained as described as follows: CuFe₂O₄+8H⁺=Cu⁺+2Fe³⁺+4H₂O
Increases of temperature and acid concentration both lead to increase in dissolution rate of copper ferrite. However, increases in any of Fe³⁺, Fe²⁺ or SO₄^2-decreased the dissolution rate, that has been discussed due to the decrease of hydrogen ion activity.

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Dust suspension is a common phenomenon in and around mine sites, factories, construction areas, etc.
This research deals with the continuous measurement of the concentration of suspended particles by utilizing the light wave attenuation theory.
This consists of measuring and interpreting the attenuation of LASER beams propagated through an atmospheric space.
In previous works, the authors had confirmed the relationship between the degree of attenuation of He-Ne LASER (α) due to airborne dust and dust concentration (W).
And this relationship was examined by the numerical computation of the light wave attenuation theory.
Then, the numerical values were compared with the experimental results obtained by the measurements of α and W.
As a result, it has been confirmed that αis proportional to W for various kinds of airbone dust, and that the theoretical values of a are coincide with the experimental values.
Lately, based on the light wave attenuation theory, an in-situ measurement system was designed.
In-situ measurement experiments were performed and the results are included in this report.
Measurement results in the AOMORI-HAKODATE tunnel are shown for illustration.
Lastly, the practicability of this method was considered by comparing the capability with other instruments.

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