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Ferroelectric BiFeO 3 thin films with Nd–Cr (or Sm–Cr) co-substitution (denoted by BNdFCr and BSmFCr, respectively) were deposited on the Pt(2 0 0)/TiO 2 /SiO 2 /Si(1 0 0) substrates by a chemical solution deposition method. X-ray diffraction patterns revealed the formation of BNdFCr and BSmFCr thin films without any secondary phases. The co-substituted BNdFCr (or BSmFCr) thin films, which were annealed at 550 °C for 30 min in N 2 atmosphere, exhibited enhanced electrical properties compared to BFO thin films with the remanent polarization (2 P r ) and coercive electric field (2 E c ) of 196, 188 μC/cm 2 and 600, 570 kV/cm with the electric field of 800 kV/cm, respectively. The leakage current densities of BNdFCr and BSmFCr thin films measured at room temperature were approximately three orders of magnitude lower than that of BFO thin film, and the leakage current at room temperature of the thin films exhibited three distinctive conduction behaviors. Furthermore, the values of pulse polarizations [i.e., +( P *– P ^ ) or −( P *– P ^ )] of BNdFCr and BSmFCr thin films were reasonably unchanged up to 1.4 × 10 10 switching cycles.

The Bi3.4La0.6Ti3O12 (BLT) thin film and powder have been prepared by a sol-gel method with annealing at 700∘C. Randomly oriented BLT thin film exhibits a large remanent polarization, 2P r = 72 μC/cm2, with a dc applied field strength of 320 kV/cm. Structure of sol-gel derived BLT powder has been investigated by neutron scatterings, and refined by a Rietveld method resulting a reasonable goodness of fit (wR p = 6.7%, and R p = 5.7%) using an orthorhombic (B2cb, a = 5.4221 A, b = 5.4032 A, and c = 32.8361 A). Two different TiO6 octahedra exhibit different polarization directions; (100) from Ti(1)O6, and (011) from Ti(2)O6, which explains the observed large 2P r of the randomly oriented BLT thin film.

The Bi3.4Pr0.6Ti3O12 (BPT) thin film and powder have been prepared by a sol-gel method with annealing at 700°C. Randomly oriented BPT thin film exhibits a large remanent polarization, 2P r = 62 μC/cm2. Structure of sol-gel derived BPT powder has been refined by a Rietveld method resulting a reasonable goodness of fit (wR p = 6.9%, and R p = 5.5%) using orthorhombic (B2cb, a = 5.4221 A, b = 5.4032 A, and c = 32.8361 A). Two different TiO6 octahedra exhibit different polarization directions; (100) from Ti(1)O6, and close to (111) from Ti(2)O6, which explains large 2P r of the randomly oriented BPT thin film.

Ferroelectric Cr-doped BiFeO3 (BFCr) thin films having a rhombohedrally distorted simple perovskite structure were fabricated on the p-type Si (100) substrate by the chemical solution deposition technique. The microstructures and the surface morphologies of BFCr thin films on the p-type Si (100) annealed at 550 °C for 30 min in nitrogen atmosphere were examined by an x-ray diffractometer and a scanning electron microscope, respectively. The capacitance-voltage (C−V) curves for BFCr thin film as the clockwise ferroelectric hysteresis loop were observed. Furthermore, the C−V characteristics for the metal-ferroelectrics-semiconductor structured BFCr thin films were measured as functions of the voltage and the frequency. From these results, the fixed charge density Nfc was calculated as 5.3×1011 cm−2. The leakage current characteristics of BFCr thin films were also measured by a thermally stimulated current measurement. Using the current-voltage curves, the current conduction mechanism of BFCr thin films on t...

Successful middle ear surgery requires the availability of al safe, effective bonding material. Side effect caused by synthetic materials have led to the use of biologic adhesive. However, they carry the risk of transmission of infectious diseases if they are prepared from pooled human blood. The adhesive strength of ammonium sulfate fibrin adhesive produce an adhesive strength that is half that of the homologous commercial product. It is, however, good enough for use in several otolaryngological operations, tympanoplasty, facial nerve repair, reconstruction of ossicles, reconstruction of posterior wall of ear canal and obliteration of frontal sinus and mastoid antrum using bone dust.

Ketotifen, a benzocycloheptathiophene, has an orally effective antiallergic as well as antihistaminic properties. In pervious studies, Ketotifen has shown encouraging results in patient with allergic rhinitis, either perennial or seasonal. 39 patients with allergic rhinitis had been treated with Ketotifen 1 mg twice daily for 8 weeks. And we obtained following results. 1) The efficacy rate in sneezing attack was 73.5%, in nasal discharge 71%, in nasal obstruction 58%. 2) Some improvements in at least one of three major symptoms were noted within 1 week in 30.7%, within 2 weeks in 55.8%, within 3 weeks in 66.7%, within 8 weeks in 87.2%. 3) Physical findings such as colour, swelling of turbinate, character of rhinorrhea were not improved significantly. 4) Side effect was observed only in one patient with abdominal pain and diarrhea, which was subsided after interruption of administration. These results suggested that Ketotifen was effective in treatment of allergic rhinitis.

Inverted papilloma arising from mucous membrane of the nasal cavity and paranasal sinuses is rare benign neoplasm, and usually unilateral arise from lateral wall of nasal cavity. This tumor is histologically benign neoplasm but clinically malignant, because of frequent recurrence and extensive bone destruction. And occasionally, this tumor can be transformed to squamous cell carcinoma or verrucous carcinoma. Recently, We have experienced a case of the inverted papilloma with verrucous carcinoma of the nose and paranasal sinuses and patient expired due to extension of intracranial cavity. We report our case with review of current literatures.