Water-insoluble lipoprotein lipase (LPL) was prepared by immobilizing LPL onto the surface of porous copoly (γ- methyl-L-glutamate / L-leucine) (ML) beads with and without spacer.The mode of theimmobilization between LPL and porous copolypeptido ML beads was covalent fixation.The relative activity and the stability of the immobilized LPL was investigated.The retained activity of the LPLcovalently immobilized by the azide method was found to be excellent toward a small ester substrate,p-nitrophenyllaurate (pNPL). The values of the Michaelis constant Km, and the maximum reaction velocityVm for free and immobilized LPL on the porous copolypeptide ML beads were estimated.Apparent Kmwas larger for immobilized LPL than for the free one, while Vm was smaller for the immobilized LPL.The thermal stability of the covalently immobilized LPL was higher than that of the freeLPL.The initial enzymatic activity of the immobilized LPL remained approximately unchanged withstorage time, when the batch enzyme reaction was performed repeatedly, indicating the excellent durability.

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We have studied the relation between scratch resistance and organic substituent(R) of alkoxy silane hydrolysate (RSi(OH)3), and the following results were obtained.(1) In order to improve the scratch resistance of film, it's necessary that the steric hindrance of substituent is decreased in the cource of condensation reaction.(2) Methyl group is the best substituent.(3) It is unable to obtain high scratch resistance in the substituent of more than 2 carbon atoms, because of less of cross-linkage structure.(4) The coating materials which consist of methyl group silane and vinyl group silane not only give the excellent scratch resistance, but also improve the adhesion for all of PMMA substrate.

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The information of the bond strength development after gluing is very important for the execution management of an adhesively jointed wood structure. From the viewpoint, bonding test and dynamic viscoelasticity measurement of the resin films were performed, and correlation of both the obtained results was investigated. The wood single lap specimens for adhesion tests were prepared using the commercial room temperature setting epoxy resin adhesives and tested after curing at 20℃ to 60℃ which was the onsite conditions to be encountered in actualgluing. Furthermore, the dynamic viscoelasticity of the resin films which cured in the condition same as the adhesion test was measured. The results of dynamic viscoelastic measurement revealed that epoxy resin cured to a certain level with rise of temperature, or progress of time, and the cured resin at the different temperature did not show accordant cure degree. On the other hand, while the bond performance improved with the rise of cure temperature, and progress of cure time, the bond strength of wood joints was hardly affected by the cure degree. It is so that this case, the bond strength of wood joints depends on the intensity of the wood itself.

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