Elemental technological challenges required for the development of flexible solar cells have been clarified and a consortium system to solve the problems has been established based on industry-academia-government collaboration. The technology to form texture on polymer substrates indispensable for high efficiency has been developed, and we have succeeded in preparation of thin-film silicon solar cells on polymer substrates whose efficiency is comparable with that of cells prepared on glass substrates. The stage has already moved from research within the consortium to practical realization research in individual enterprises. Establishment process, management policy, patent strategy and training of young researchers of the consortium are described in this paper.

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Concerning the geological disposal system of high-level nuclear waste, the term subject to safety assessment of the system after closure is considered to exceed several hundred thousand years. We are faced with the major issues of how to guarantee such long-term safety and on what kind of criteria the system should be regulated. Because the Japanese islands lie in the mobile belt where earthquakes and volcanic activities often occur, a variety of geological issues required for the safety assessment have to be taken into consideration. In this paper, issues are extracted from a series of facts or scenario where incidents occur one after another provoked by one incident, and one such example is given of analysis results of the eruption history of volcanic activities. A methodology for long-term forecast addressing the causes of geological phenomena is also presented.

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Reliable pressure measurements provide the basis for all activities in society and industry, and every country shows considerable interest in them in international trade. Recently, characteristics of industrial digital pressure gauges and the short- and long-term stabilities as well as the stability under environmental change and during transportation have been improved remarkably. AIST focused its attention on the technological advancement, and, after evaluating the characteristics of digital pressure gauges in detail, incorporated them to some phases in the metrology system, which are the upgrading of national pressure standards, the international comparisons of the standards and the domestic traceability system. Consequently, the reliability of pressure measurements in industrial fields has been secured through an efficient process, and the international mutual recognition has been promoted by carrying out many international comparisons.

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Conversion processes of organic compounds using biocatalyst generally have high regio- and stereo-selectivity, and are becoming increasingly important for efficient production of chemicals. In addition, biocatalysis is less hazardous, less polluting and less energy-consuming than the conventional chemical method. We report the highly efficient bioconversion system using actinomycete Rhodococcus erythropolis to produce active form of vitamin D₃ currently used as a pharmaceutical. The improvement of performance of the enzyme used for the bioconversion has been achieved by the combination of evolutionary engineering and structure-based methods. Accordingly, the practical production efficiency of active form of vitamin D₃ has been substantially increased. In addition, we have succeeded in significant improvement of cellular permeability of vitamin D₃ by using nisin-treated cells, and have developed a new platform for vitamin D₃ hydroxylation process.

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[in Japanese]

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