A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Crystalline morphologies at the surface of PET/PEN random copolymer films

A series of PET (poly(ethylene terephthalate))/PEN (poly(ethylene 2,6‐naphthalate)) copolyesters were synthesized by molten transesterification, and the surface crystallization behavior of their thin films investigated by atomic force microscope with an in situ heating stage. Force‐distance measurements detected a surface glass transition (T gS) of the copolymers several tens of degrees below their bulk glass transition (T gB) obtained by differential scanning calorimeter. The surface crystalline morphologies as a function of annealing temperature and film thickness were summarized as surface morphology diagrams. The surface crystallization temperature (T cS) was found to be several degrees lower than the bulk crystallization (T cB), and the films thinner than ~100 nm showed significant increase in T cB. The lamellar crystalline morphology of copolymers with high randomness and short sequence length deviated from that of the homopolymers, reflecting the composition and degree of randomness. Highly random PET/PEN = 75/25 wt% copolymers exhibited unique lamellar curvature with arbitrary growth directions. Sharp boundaries between the crystals and amorphous suggested an absence of large amounts of rejected material at the growth front. In the case of copolymers with high randomness and short sequence length, no bulk crystallization morphology was observed even at 190°C, with the relatively thick surface crystalline layer totally covering the emergence of any bulk crystals. </p

Crystalline morphologies at the surface of PET/PEN random copolymer films

A series of PET (poly(ethylene terephthalate))/PEN (poly(ethylene 2,6‐naphthalate)) copolyesters were synthesized by molten transesterification, and the surface crystallization behavior of their thin films investigated by atomic force microscope with an in situ heating stage. Force‐distance measurements detected a surface glass transition (T gS) of the copolymers several tens of degrees below their bulk glass transition (T gB) obtained by differential scanning calorimeter. The surface crystalline morphologies as a function of annealing temperature and film thickness were summarized as surface morphology diagrams. The surface crystallization temperature (T cS) was found to be several degrees lower than the bulk crystallization (T cB), and the films thinner than ~100 nm showed significant increase in T cB. The lamellar crystalline morphology of copolymers with high randomness and short sequence length deviated from that of the homopolymers, reflecting the composition and degree of randomness. Highly random PET/PEN = 75/25 wt% copolymers exhibited unique lamellar curvature with arbitrary growth directions. Sharp boundaries between the crystals and amorphous suggested an absence of large amounts of rejected material at the growth front. In the case of copolymers with high randomness and short sequence length, no bulk crystallization morphology was observed even at 190°C, with the relatively thick surface crystalline layer totally covering the emergence of any bulk crystals

Improvement of thermal stability of NO oxidation Pt/Al2O3 catalyst by addition of Pd

The present work has been undertaken to tailor Pt/Al2O3 catalysts active for NO oxidation even after severe heat treatments in air. For this purpose, the addition of Pd has been attempted, which is less active for this reaction but can effectively suppress thermal sintering of the active metal Pt. Various Pd-modified Pt/Al2O3 catalysts were prepared, subjected to heat treatments in air at 800℃ and 830℃, and then applied for NO oxidation at 300℃. The total NO oxidation activity was shown to be significantly enhanced by the addition of Pd, depending on the amount of Pd added. The Pd-modified catalysts are active even after the severe heat treatment at 830℃ for a long time of 60 h. The optimized Pd-modified Pt/Al2O3 catalyst can show a maximum activity limited by chemical equilibrium under the conditions used. The bulk structures of supported noble metal particles were examined by XRD and their surface properties by CO chemisorption and EDX-TEM. From these characterization results as well as the reaction ones, the size of individual metal particles, the chemical composition of their surfaces, and the overall TOF value were determined for discussing possible reasons for the improvement of the thermal stability and the enhanced catalytic activity of Pt/Al2O3 catalysts by the Pd addition. The Pd-modified Pt/Al2O3 catalysts should be a promising one for NO oxidation of practical interest