ABSTRACT
The infiltration depth and water vapor transmission rate (WVTR) were explored in a variety of Al2O3-polymer hybrid layers as thin gas barrier films by filling the free volumes of polymers in the subsurface region with Al2O3 using the atomic layer infiltration (ALI) method. Among all, the prepared Al2O3-polyethylene terephthalate (PET), Al2O3-polyimide, and Al2O3-Nylon 6 hybrid thin layers with the infiltration depth in the nanometer ranges showed extremely low WVTR values (<10-6 g m-2 day-1) in a Ca dot corrosion test. Furthermore, we observed selective infiltration among the two polymers [perfluoroalkoxy alkane (PFA) and PET] by a preferential growth of Al2O3 in the PET polymer that might be based on effective functional group anchoring in the ALI process. Then, we demonstrated a novel strategy by employing such a selective infiltration procedure and encapsulating individual segments of 144 Ca dots by Al2O3-PET hybrid thin films on the PFA polymer substrate rather than wrapping the whole thing together for the stretchable gas-encapsulation film. Regardless of stretching, it showed an extremely low WVTR (<10-7 g m-2 day-1) and is proposed as a highly promising hermetic sealing alternative in stretchable, flexible, and foldable electronic display technologies.
ABSTRACT
Ultrahigh crystalline TiO2 nanotubes were synthesized by hydrogen peroxide treatment of very low crystalline titania nanotubes (TiNT-as prepared), which were prepared with synthesized TiO2 nanoparticles by hydrothermal methods in an aqueous NaOH solution. Thus, prepared ultrahigh crystalline TiO2 nanotubes (TiNT-H2O2) showed comparable crystallinity with high crystalline TiO2 nanoparticles. The details of nanotubular structures were elucidated by high resolution-transmission electron microscopy (HR-TEM), field emission-scanning electron microscopy (FE-SEM), energy-dispersive X-ray analysis in transmission electron microscopy (TEM-EDX), X-ray diffraction (XRD), photoluminescence (PL), and BET surface area. TiNT-H2O2 was found to be a multiwalled anatase phase only with an average outer diameter of approximately 8 nm and an inner diameter of approximately 5 nm and grown along the [001] direction to 500-700 nm long with an interlayer fringe distance of ca. 0.78 nm. The photocatalytic activity of TiNT-H2O2 was about 2-fold higher than those of TiNT-as prepared, synthesized TiO2 nanoparticles, and TiO2-P25 (Degussa) in the photocatalytic oxidation of trimethylamine gas under UV irradiation.
Subject(s)
Nanotubes/chemistry , Titanium/chemistry , Catalysis , Crystallization , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Nanotubes/ultrastructure , Photochemistry , Spectrum Analysis , X-Ray DiffractionABSTRACT
In the present study, we have evaluated prophylactic role of various immunomodulators viz. lipopolysachharide, protein A and tuftsin to impart protection against experimental candidiasis in leukopenic mice. Both free as well as liposomised form of nystatin was not effective enough in offering complete cure against less susceptible isolate of Candida albicans (JNMCR) infection in immunodebilitant mice. Interestingly, the pretreatment of leukopenic mice with immunomodulators before challenging them with C. albicans increased therapeutic efficacy of the nystatin against systemic candidiasis. Efficacy of the treatment was evaluated on the basis of survival of the animals as well as fungal load in systemic circulation and various organs viz. liver, kidney, spleen and lungs of the treated animals.
