Abstract: A hydroponic cultivation system includes a plurality of seedbeds, a hanging part, and a transport mechanism. A plurality of seedlings of a plant to be cultivated is transplanted to side surfaces of the plurality of seedbeds. The hanging part hangs each of the plurality of seedbeds while the plurality of seedbeds is arranged in a predetermined horizontal direction from a planting side of the seedlings to a harvesting side of the seedlings. The transport mechanism transports the plurality of seedbeds in the predetermined horizontal direction while widening spaces between the seedbeds in the predetermined horizontal direction in a stepwise or continuous manner.

Abstract: [Object] To provide a hydroponic cultivation system that is capable of transporting a seedbed with a simple mechanism and has excellent durability. [Solving Means] A hydroponic cultivation system includes a plurality of seedbeds, a hanging part, and a transport mechanism. A plurality of seedlings of a plant to be cultivated are transplanted to side surfaces of the plurality of seedbeds. The hanging part hangs each of the plurality of seedbeds while the plurality of seedbeds are arranged in a predetermined horizontal direction from a planting side of the seedlings to a harvesting side of the seedlings. The transport mechanism transports the plurality of seedbeds in the predetermined horizontal direction while widening spaces between the seedbeds in the predetermined horizontal direction in a stepwise or continuous manner.

Abstract: The object of the present invention is to provide a polyimide precursor solution having a good coating workability. Another object of the present invention is to provide transfer and fixing parts such as a polyimide seamless belt and the like produced from said polyimide precursor solution. Said polyimide precursor solution is produced by dissolving said polyimide precursor which is a homopolymer or copolymer of a polyamide acid in a solvent mixture of one or more kind(s) of solvent having a lower boiling point under 100° C., and one or more kind(s) of solvent having a higher boiling point of 100° C. or more, wherein said higher boiling point solvent (s) is (are) contained in said solvent mixture in an amount of 5 to 55% by weight.