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A capillary tube viscometer was developed to measure the dynamic viscosity of gases for high pressure and high temperature. The apparatus is simple and designed for safe-handling operation. The gas was supplied to the capillary tube from a high-pressure reservoir tank through a pressure regulator unit to maintain a steady state flow. The measurements of a pressure drop across the capillary tube with high accuracy under extreme conditions are the main challenge for this method. A differential pressure sensor for high pressures up to 100 MPa is not available commercially. Therefore, a pair of accurate absolute pressure transducers was used as a differential pressure sensor. Then the pressure drop was calculated by subtracting the outlet pressure from the inlet one with a resolution of 100 Pa at 100 MPa. The accuracy of the present measurement system is confirmed by measuring the viscosity of nitrogen as a reference gas. The apparatus provided viscosities of nitrogen from ambient temperature to 500 K and hydrogen from ambient temperature to 400 K and for pressures up to 100 MPa with a maximum deviation of 2.2 % compared with a correlation developed by the present authors and with REFPROP (NIST).

壁面緑化に期待される都市環境改善効果を把握することを目的として，2005 年日本国際博覧会(愛・地球博)に登場した大規模緑化壁(バイオラング)を用いて，暑熱環境改善効果や生物誘因効果に関する調査を実施した。その結果，壁面緑化には暑熱環境の改善効果があること，壁面緑化に導入する植物を工夫することで，多くの生物が壁面緑化に集まり，繁殖する環境の創出が期待できることが示唆された。また，バイオラングの見学者はバイオラングに良いイメージを持ち，都市環境改善効果について高い期待を寄せていることが示された。