Novel PEEK Copolymer Synthesis and Biosafety - I: Cytotoxicity Evaluation for Clinical Application.

In this research, we synthesized novel polyetheretherketone (PEEK) copolymers and evaluated the biosafety and cytotoxicity of their composites for spinal cage applications in the orthopedic field. The PEEK copolymers and their composites were prepared through a solution polymerization method using diphenyl sulfone as a polymerization solvent. The composite of PEEK copolymer showed good mechanical properties similar to that of natural bone, and also showed good thermal characteristics for the processing of clinical use as spine cage.

Very high third-order nonlinear optical activities of intrazeolite PbS quantum dots.

Zeolite-intercalated semiconductor quantum dots (QDs) have long been proposed to give very high third-order nonlinear optical (3NLO) responses. However, measurements of their 3NLO responses have not been possible due to the lack of methods to prepare optically transparent QD-incorporating zeolite films supported on optically transparent substrates and to confine QDs only within zeolite interiors. We found that the zeolite-Y films grown on indium-tin-oxide-coated glass plates (Ygs) remain firmly bonded to the substrates during ion exchange with Pb2+ ions, drying, and formation of PbS QDs by treating Pb2+ ions with H2S.

Picosecond pump-probe measurement of bandgap changes in SiO2/TiO2 one-dimensional photonic bandgap structures.

A picosecond pump-probe nonlinear optical measurement is performed in SiO2/TiO2 one-dimensional photonic bandgap structures fabricated by a solgel method. Both high and low band edges were examined by varying the probe wavelengths and angle tuning was also employed to further clarify the mechanism of a nonlinear optical response. The third-order nonlinear optical response in one-dimensional photonic bandgap structures that comprise TiO2 films is responsible for the nonlinear optical transmissions at both bandgap edges, with an 8% decrease at the low-energy edge and a 4.

Aligned inclusion of hemicyanine dyes into silica zeolite films for second harmonic generation.

Silicalite-1 films (thickness = 400 nm) supported on both sides of glass plates (SL/G) were prepared, and hemicyanine dyes (HC-n) with different alkyl chain lengths (n, n = 3, 6, 9, 12, 15, 18, 22, and 24) were included into the silicalite-1 films by dipping SL/Gs into each methanol solution of HC-n (1 mM) for 1 d. The included numbers of HC-n per channel (N(C)) generally decreased with increasing n; that is, they were 6.4, 23.