Search

Partially nitrided LiCoO2 thin films with stoichiometric contents of Li and Co were fabricated on sapphire substrates using an ethanol solution. The precursor films were formed by spin-coating. By thermal treatment of' the precursor films at 350, 450, 550 and 650°C for 30 min in air, four kinds of LiCoO2 thin films were obtained. That annealing of the precursor film at 650°C resulted in the nucleation of Co3O4 from the layered LiCoO2, which has been confirmed by the Raman spectrum. Three X-ray photoelectron spectroscopy peaks observed at 527.9 eV, 402.1 eV, and 396.2 eV were newly assigned to the O-Co4+, N-Co4+, and N-Co2+ bonds, respectively, using a peak-analysis technique. The resistivity of the layered LiCoO2 thin film fabricated at 650°C was measured to be 1.2 Ω cm. [ABSTRACT FROM AUTHOR]

The p-type Cu2O thin films on a quartz glass substrate were facilely fabricated at 180°C in air by spraying aqueous precursor solutions. The spray solutions were prepared in a diluted ammonia solution by dissolving Cu(II) formate and ammonium formate whose molar ratios to Cu(II) ion were 0, 2, 6 and 14. In the cases of the molar ratios at 6 and 14, the Cu2O thin films of 140 and 350 nm thickness respectively indicated a highly photocatalytic activity under visible-light irradiation of 0.45 mW cm–2, and the pseudo-first-order rate constants of 0.056 and 0.087 min–1 were respectively obtained by tracing the discoloration of a methyl orange solution. The O-defect site was found in the Raman spectra of these photocatalytic thin films whose adhesion strength onto the quartz substrate were larger than 5.6 N. The morphology, chemical component, and optical and electrical properties were also examined in detail. [ABSTRACT FROM AUTHOR]

Epitaxial growth of Cu3N films on (0001)α-Al2O3 substrates was performed by mist chemical vapor deposition. As a source solution, 0.10 mol l−1 of copper (II) acetylacetonate dissolved in 28% aqueous ammonia was used. Even though an aqueous solution was used as the source solution, the epitaxial Cu3N film was realized without the incorporation of CuO and Cu2O phases in the growth of 300 °C. The film was also found to have limited O incorporation from the results of scanning transmission electron microscopy and Rutherford back-scattering spectroscopy. The optical property of the Cu3N film was also investigated. [ABSTRACT FROM AUTHOR]

In2O3 films were epitaxially grown on (0001)α-Al2O3 substrates by mist CVD, and the impact of hydrochloric acid (HCl) was investigated by varying the HCl concentration in the source solution. Single-phase rhombohedral corundum-type In2O3 films, without the incorporation of body-centered cubic bixbite-type In2O3 phases, could be successfully grown directly on α-Al2O3 substrates by controlling only the HCl concentration. In growth by mist CVD, adding HCl to the source solution was found to affect not only the dissolution of the source precursor but also the growth kinetics of phase control, surface migration and impurity incorporation. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate human osteoblast activity on thin hydroxyapatite (HA)-coated three-dimensional scaffolds made of titanium fiber web. Materials and Methods: A thin HA film was coated on a titanium fiber web by the molecular precursor method. Human osteoblasts were disseminated onto the uncoated and HA-coated titanium fiber web, and osteoblast activity was observed at days 3, 7, 14, and 21 of culture. Results: Proliferation activities of osteoblasts were significantly higher in the uncoated titanium fiber web. Osteoblasts in the uncoated titanium fiber web showed a typical expression pattern, but those in the HA-coated titanium fiber web showed rapid osteocalcin expression and calcification at an early stage of culture. Moreover, osteocalcin expression per osteoblast was significantly higher in the HA-coated group. Conclusion: These results suggest that HA coating with the molecular precursor method accelerated osteoblast functional activity. [ABSTRACT FROM AUTHOR]

Purpose: The influence of thin carbonate-containing apatite (CA) coating on the trabecular bone response to titanium implants was investigated. Materials and Methods: Thin CA coatings were deposited by a new method known as the molecular precursor method. Using a precursor solution composed of an EDTA-calcium complex, a CA film was deposited on the titanium surfaces. Uncoated and CA-coated titanium were placed in the trabecular bone of the left and right femoral condyles of 16 rabbits. After implantation periods of 2, 4, 8, and 12 weeks, the bone-implant interface was evaluated histologically and histomorphometrically. Results: Histologic evaluation revealed new bone formation around the uncoated and CA-coated implant surfaces after only 4 weeks of implantation. After 12 weeks, mature trabecular bone surrounded all implants. At 4 and 8 weeks of implantation, no differ- ence existed in bone contact between uncoated and CA-coated implants. After 12 weeks of implanta- tion, the CA-coated implant group showed a significantly higher percentage of bone contact than the uncoated implant group. Discussion and Conclusion: The present study demonstrated that thin CA coatings applied using the molecular precursor method showed greater bone-to-implant contact during the healing phase than uncoated controls. The results were similar to those observed with implants with calcium phosphate coatings deposited with a physical vapor deposition technique. INT J ORAL M~x- ILLOFAC IMPLANTS 2006;21:851-858 [ABSTRACT FROM AUTHOR]

Background Recent advances in high-resolution (HR) magnetic resonance angiography (MRA) using ultrahigh-field systems enable direct visualization of the lenticulostriate arteries (LSAs), which had been hardly achieved by conventional MRA. Hence, by using HR-MRA at 7 T, we attempted to assess occlusive changes in the LSAs in patients with LSA territorial infarcts. Methods We prospectively examined 34 consecutive patients with acute ischemic stroke in the LSA territory using a 7 T scanner. We measured the lengths of the relevant LSAs on HR-MRA and the diameters/volume of the infarcts and compared these between the patients with/without occlusive changes in the LSAs. Results On HR-MRA, occlusion of the LSAs was observed in 19 (59%) of 32 patients who were eligible for the analyses. The curved/straight lengths of the LSAs in the patients with LSA occlusion (23.1–31.1/17.8–24.3 mm) were significantly shorter than in those without apparent LSA occlusion (25.8–39.5/24.0–30.4 mm) (P = 0.027/0.003). The anteroposterior/superoinferior diameters of the infarcts were significantly larger in the occluded-LSA group (14.5–21.4/14.9–22.2 mm) than in the intact-LSA group (10.9–16.8/10.8–16.2 mm) (P = 0.041/0.011). In addition, the curved lengths of the relevant LSAs showed significant correlations with the superoinferior diameters of the infarcts (r = 0.38, P = 0.034). Conclusion Occlusive changes in the LSAs were frequently found in patients with acute ischemic stroke within the LSA territory when using HR-MRA at 7 T and were substantially related to superoinferior extension of the infarcts. [ABSTRACT FROM AUTHOR]

ZnO films dispersed with Ag-nanocrystals (Ag-NC/ZnO) were fabricated by the molecular precursor method. Electrical and optical properties of the films and their application in the GaInN-based blue LEDs were studied through the observations of photoluminescence (PL) spectra and analytical simulations. Although the enhancement of the blue LED emission could not be observed, the PL spectra exhibited additional emission peaks in the yellow spectral region. Judging from their spectral shape, near-band-edge emissions were found to be replicated by the local surface plasmon resonances. [ABSTRACT FROM AUTHOR]