To make clarify the pollution mechanism of the fog which occurs in Yamase, which is a local weather phenomenon in summer of cold wind blown from the edge of the Okhotsk Sea high-pressure region to the northern Pacific coast ofJapan, fog water samples were collected at Akita Hachimantai in 2003. The Yamase fog pollution level is lower than that of usual weather conditions. The total ion, nss-SO₄^2- and NO₃^- concentrations of fog water in Yamase are lower than those of other wind directions. Therefore the pH of fog water in Yamase is higher than other cases and the Yamase fog is not acidified. The component ratio of NH₄⁺ of fog water in Yamase is higher than that of nss-SO₄^2- because fog droplets would take up gaseous NH₃ generated from the ground surface, rather than (NH₄)₂SO₄.

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We carried out laboratory hydraulic fracturing tests, which revealed that the pressure at the reopening and closing of fractures during hydraulic fracturing can be detected by monitoring the strains in the borehole wall and the triggering of acoustic emissions.
In the experiments, we measured the pressures during the reopening and closing of a fracture caused by elastic restitution in a block of rock not subjected to compressive load. The pressures are used for correcting those obtained in blocks of rock when biaxial compressive load is applied.
The reopening pressure (P_r)is smaller than that obtained by the conventional method. This result expresses the following theoretical relationship.
P_r=(3S_h-S_H)/2
where S_H is the maximum horizontal stress, and S_h is the minimum horizontal stress.
The corrected reopening pressure of fracture agrees to within 0.7 MPa with that obtained from the above equation.

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In the present work, the fine grinding of limestone was performed by using a super centrifugal mill (SC-mill) which was a kind of circular-type stirred mill. The effects of the grinding conditions in the SC-mill such as the rotor speed, the grinding time, the mass of the grinding media, and the mass of the feed sample (or slurry concentration) on the fine grindability of limestone were investigated. As the results, the mass and the specific surface area of the fine particles produced by the SC-mill could be expressed as a function of the grinding conditions as mentioned above.

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Two kinds of pyrene modified β-cyclodextrins, which are different in linker parts to bind between β-cyclodextrin and pyrene unit, were synthesized. Those derivatives show different behavior for single and double strands of DNA, where short linker derivative shows no interaction for DNA, but longer linker derivative indicates there are something interaction for DNA by intercalating of pyrene unit.

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