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In order to evaluate the decay gamma ray dose rate in the DT nuclear fusion reactor, we developed the Monte Carlo decay gamma ray transport calculation system. By connecting the Monte Carlo calculation code with the activation one, we successfully developed the calculation system. The decay gamma ray dose rates after shutdown calculated by the developed system agree well with the experimental results performed by FNS at JAERI within the experimental error of 10%. We also successfully developed the variance reduction method for the decay gamma ray generating source. It is confirmed that the calculation time can be drastically reduced by applying the developed method. The present calculation system will be useful for the evaluation of the decay gamma ray dose rate in the DT nuclear fusion reactor.

An organic–inorganic hybrid material was prepared from a pentacyclo[9.5.1.1^3,9.1^5,15.1^7,13]octasiloxane bearing eight coumarin groups. The coumarin groups were photodimerized by UV-light irradiation to connect the monomer units of the octasiloxane. Using a concentrated solution, the intermolecular photodimerization of these coumarin groups leaded to the cross-linking of the octasiloxane, fabricating an organic–inorganic hybrid material with a three-dimensional nanostructure. Whereas in dilute solution the intramolecular photodimerization was preferred to the intermolecular reaction, resulting in no formation of polymeric material.

Crocus sativus lectin (CSL) is one of the truly mannose-specific plant lectins that has a unique binding specificity that sets it apart from others. We studied sugar-binding specificity of CSL in detail by a solution phase method (fluorescence polarization) and three solid phase methods (flow injection, surface plasmon resonance, and microtiter plate), using a number of different glycopeptides and oligosaccharides. CSL binds the branched mannotriose structure in the N-glycan core. Substitution of the terminal Man in the Manalpha(1-3)Man branch with GlcNAc drastically decreases binding affinity much more than masking of the terminal Man in the Manalpha(1-6)Man branch. Most interestingly, the beta-Man-linked GlcNAc in N-glycan core structure contributes greatly to the binding. The effect of this GlcNAc is so strong that it can substantially offset the negative effect of substitution on the nonreducing terminal Man residues. On the other hand, the GlcNAc that is usually attached to Asn in N-glycans and the l-Fuc linked at the 6-position of the GlcNAc are irrelevant to the binding. A bisecting GlcNAc neither contributes to nor interferes with the binding. This unique binding specificity of CSL offers many possibilities of its use in analytical and preparative applications.

The cross-linking polymerization of diallyl terephthalate (DAT) was explored in detail in the presence of microgel-like poly(allyl methacrylate) (PAMA microsphere) as an extension of our continuing studies concerned with the elucidation of cross-linking reaction mechanism and the control of network formation in the free-radical cross-linking polymerization of multivinyl compounds. Thus, PAMA microspheres were prepared by the emulsion polymerization of AMA as reactive cross-linked polymer microspheres having abundant pendant allyl groups. The polymerization of DAT in the presence of microsphere was conducted in bulk using BPO as initiator at 80 °C. The gel-point conversion became higher with an increase in the feed amount of microsphere. No gel effect was observed. Variation of RI-monitored SEC curves with conversion suggested the copolymerization of the pendant allyl groups present on the surface of microsphere with DAT; this was also supported by light scattering and ¹H NMR spectroscopy. The swelling ratios of the gels in the presence of microsphere were not high even just beyond the gel points, suggesting a preferential incorporation of microsphere into the gel. These are discussed mechanistically.

In this paper, a new procedure of selecting weighting matrices in linear quadratic optimal control problems (LQ-probleras) is proposed. In the LQ-problem, the quadratic weights are usually decided on trial and error to get good responses. But using the proposed method, the quadratic weights are decided in such a way that all poles of the closed loop system are located in the desired region for good response as well as for stability. As the closed loop system constructed by this method has merits of an LQ-problem as well as a pole-assignment problem, this procedure will be useful for designing a linear feedback system