Stress corrosion index is one of the important parameters to express subcritical crack growth within the rock. The mechanism of stress corrosion is influenced by the chemical effect of water in the rock and the surrounding environment. There are some laboratory tests to estimate stress corrosion index such as the double torsion test, the uniaxial compression test under various strain/stress loading rates, the uniaxial compression test and disc test under various water vapor pressures. However, since the conditions such as geometry and state of stress of the specimen and the surrounding environment are different in each test, it is likely that the stress corrosion indexes from these tests could be different.
In this paper, we compared stress corrosion indexes of Kumamoto andesite obtained by three types of laboratory test. The tests included the uniaxial compression test and the disc test under various water vapor pressures, and double torsion test under a constant surrounding environment. The stress corrosion indexes were estimated to be 44 in the uniaxial compression test, 43 in the disc test and 37 in the double torsion test. These values were considered to be similar, though the value in the double torsion test was slightly smaller than the others. Furthermore, both stress corrosion indexes of another Kumamoto andesite obtained by the uniaxial compression tests under various water vapor pressures and various strain loading rates were the same values. Therefore, it is considered that a stress corrosion index is not affected by the experimental method and experimental environment very much and could be one of the material constants of the rock.

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To produce non-ferrous metals, the SO₂ gas is also generated from the raw material such as sulfide or sulfate. A process that produces Elemental sulphur from non-ferrous smelter gas and waste plastics was investigated.
Polyethylene was used as a deoxidizer of SO₂ gas in the present study. The conditions for reaction of SO₂ and polyethylene to make gas mixtures of H₂S and SO₂ were calculated thermodynamically. The Claus reaction was applied to produce elemental sulphur from H₂S and SO₂ gas mixture. More than 90% sulphur recovered from SO₂ gas in small experimental furnaces used in the present study.

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A significant amount of the industrial waste is sludge, which must be reduced and directed to recycling. Many municipalities find it important to develop disposal options of sewage sludge as an alternative to landfill or incineration. Carbonization is a valid process for facilitating sludge handling and decreasing environmental risks, while it increases the recycling rate.
The thermal characteristics of carbonized tablets made from sewage sludge as a biomass were analyzed with DSC (differential scanning calorimetry) and a calorimeter. The results show that the heating value , or the calorific power, of the tablets was approximately 10.5 to 15.9kJ/g and corresponded to nearly 39 to 59 % of that of charcoal. It was dependent on the heating temperature and time in carbonization. The other functions of the porous carbonized tablets as manure, water retention, and humidity control material were studied with vegetation monitoring and water retention test.

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Potentiostatic electrodeposition behavior of dendritic copper from acidic copper(I) chloride (cuprous chloride) bath containing sodium chloride and sodium bromide was investigated. The morphology, or appearance, of copper dendrite and sodium content in the dendrite as an impurity were both influenced by deposition potential (0 to -150 mV vs. SHE), bath temperature (R.T. to 60°C) or Cu(I)-ion concentration (0.35 to 1.14 mol dm^-3) investigated, while current efficiency for the deposition was 99% or more irrespective of the deposition condition investigated. Bath pH did not affect the deposition behavior within pH 0 to 2. Bath temperature was found to be the most important factor influencing the deposition current. The deposition behaviors were discussed with the potential-pH diagram of the Cu-Cl-H₂O system.

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