Abstract: A rotary-wing aircraft includes a fuselage, and an external device. The fuselage is provided with a rotary wing. The external device is mounted on the outside of the fuselage. The external device includes a mounting device, a mass variation device, and a damper. The mounting device is fixed to the fuselage and disposed so as to project in a lateral direction of the fuselage. The mass variation device is mounted on the mounting device and has mass that varies as the mass variation device is used. The damper couples the fuselage to the mounting device and supports the mounting device. The damper includes a stiffness variable mechanism configured to change stiffness of the damper in response to variation in the mass of the mass variation device.

Abstract: In a non-agitated, countercurrent flow type liquid-liquid contacting tower, trays consisting of column plates and dams are installed horizontally inside the tower shell alternately in vertical direction with a suitable interval. The column plate share a part of the cross-section of the tower to provide a flow channel or channels for the liquids, and the dam extends from the end of the column plate vertically downward and has openings near the column plate. The liquid-liquid contactor has high contacting efficiency, and thus relatively small sized apparatus can have a large treatment capacity. Because the apparatus has no moving element, maintenance is easy.

Abstract: Phenols such as cresol, phenol and xylenol etc. are obtained by thermal decomposition of a lignin-containing material in a state of a mixture of the lignin-containing material and a double ring aromatic hydrocarbon solvent.Spent liquid of a solvolysis pulping process can be used as the lignin-containing raw material in the present invention for manufacturing phenols, and the phenols obtained can be utilized as the solvent in the solvolysis process resulting in cost reduction in the pulp production process by self-supplying the necessary solvent in the solvolysis process.

Abstract: A feed liquid (sugar-containing liquid) is continuously fed to a fermenter packed with an immobilized microorganism, which is obtained by immobilizing an alcohol producing microorganism on a carrier, for alcohol fermentation. The fermentation liquid is continuously taken out of said fermenter and is heated to a temperature of 35.degree. to 80.degree. C. This liquid is introduced into a flash tank maintained at reduced pressure and is divided into an alcohol-containing steam and a liquid. The alcohol-containing steam is condensed and recovered as alcohol, while the separated liquid is cooled and is cycled back to said fermenter.