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The laser ablation technique has been used to synthesize the barium titanite (BaTiO3) ferroelectric films of quality, suitable for being applied as dielectrics in 64 and 256 Mb dynamic random access memory (DRAM). The dielectric strength and constant to the films and the switching characteristics for charge storage density, writing time, and leakage current density are calculated. The superior quality of lead-zirconate-titanate ferroelectric films is a standard for the BaTiO3 film, which is superior to the Ta2O5 dielectric films.

The concentrations of the functional lipids and oils in the abraded fractions of the stored samples of hulless barley are determined. The storage of the compound is shown to have no effect on the concentrations of oil and tocopherols (Ts) but is shown to lead to major changes in sterols.

A study is conducted to develop a noninvasive method based on fluorescence polarization spectroscopy in order to measure the degree of fiber formation of extruded meat analogs. The texture profile analysis is found inadequate to describe the fiber formation whereas the visual inspection and digital imaging results of the dissected samples is found in good agreement with the new method.

Abstract We analysed cytochrome c oxidase subunit I and NADH dehydrogenase subunit I sequence variation among 29 populations of a widely ranging southwestern springsnail (Pyrgulopsis micrococcus ) and 18 regional congeners. Cladistic analyses of these sequences depict P. micrococcus as a polyphyletic composite of five well-supported clades. Sequence divergences among these clades and subclades imply the possible occurrence of as many as seven or eight cryptic species in addition to P. micrococcus . Our finding that P. micrococcus contains multiple, genetically distinct and geographically restricted lineages suggests that diversification within this highly speciose aquatic genus has been structured in large part by the operation of terrestrial barriers to gene flow. However, these sequence data also indicate that recent dispersal among hydrographically separated areas has occurred within one of these lineages, which we attribute to passive transport on migratory waterbirds. [ABSTRACT FROM AUTHOR]

Objectives: To determine knowledge and beliefs about traditional physiognomy (judging an individual's character from their facial appearance) concerning teeth among young (17-26) and middle-aged (35-44) Hong Kong adults.Methods: In a cross sectional ethnographical telephone survey, 400 adults were interviewed about 16 traditional physiognomy concerning teeth (in consultation with a Feng Shui specialist).Results: Most completed the interview (93%, 373). Over half the study group (63%, 234) claimed they had heard of aspects of physiognomy concerning teeth, and a quarter (24%, 88) believed in such ideologies. Variations in knowledge and beliefs were apparent among people of different age (P < 0.01), gender (P < 0.05), educational attainment (P < 0.01), economic status (P < 0.01), place of birth (P < 0.01) and religion (P < 0.01). Their knowledge and belief in aspects of physiognomy concerning teeth was also associated with reported use of dental services (P < 0.01).Conclusion: Among young and middle-aged adults in Hong Kong, knowledge and beliefs concerning traditional physiognomy regarding teeth is strong, and socio-demographic variations exist in these perceptions. These findings have implications for all those involved in the delivery of dental care in multicultural societies and in raising cultural awareness about traditional health beliefs. [ABSTRACT FROM AUTHOR]

We have investigated the effects of oxygen plasma treatment on the UV detection properties of ultrathin (∼20-nm-thick) ZnO epitaxial films. Highly epitaxial ZnO films grown on sapphire were exposed to oxygen-radical-rich, inductively coupled plasma, and then their UV detection properties were characterized at 325 nm wavelength using a photoconductor structure. The oxygen plasma treatment is found to dramatically enhance the UV detection properties of ZnO, reducing the decay time constant (to below 50 μs) and increasing the on/off ratio of photocurrent (to over 1000) with high UV responsivity (1–10 A/W). This result, in conjunction with the microstructural and electrical characterization results, indicates that the plasma treatment efficiently suppresses the chemisorption sites (primarily the oxygen deficiency sites) on surface and also the oxygen vacancies in ZnO, therefore results in major reduction of the chemisorption effects and the dark current, respectively. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the electron field emission characteristics of planar diamond thin film array. Deposition of diamond film on silicon substrate by chemical vapor deposition process; Effect of substrate thin gold precoating on emission current density; Application of diamond film arrays as electron emitters in flat panel display.

Investigates the necessary conditions involved in the synthesis of textured diamond films on silicon. Utilization of chemical vapor deposition in the growth of diamond films; Impact of modified bias voltage on diamond film growth; Alteration of the texture characteristics; Use of scanning electron microscopy in the morphological analysis.

Examines the knowledge and beliefs about traditional physiognomy concerning teeth among young and middle-aged adults in Hong Kong, China. Promotion of awareness of traditional health beliefs; Aspects of the delivery of dental care in multicultural societies.

Abstract: We report the investigation on the compositional-pulling effect of crystalline Al x Ga1− x N/(0001) sapphire epilayers by cross-sectional cathodoluminescence (CL) and energy-dispersive X-ray (EDX) analyses. Direct evidence for the compositional distribution was found in the Al x Ga1− x N (0

Abstract: We report a two-step growth of Al x Ga1− x N (x∼0.2) by metal-organic vapor-phase epitaxy without a pretreatment of the substrate. High-quality, crack-free and near GaN-free AlGaN was achieved with a thickness much exceeding the theoretical critical thickness of the growth of AlGaN on GaN. The method was compared with the conventional ones such as AlGaN on AlN nucleation layer and AlGaN on GaN buffer layer. In situ reflectometry monitoring indicated different behaviors of the high temperature grown AlGaN over different underlayers. The double crystal X-ray rocking curve showed a full-width at half-maximum of only 500arcsec for the 1.7μm Al0.2Ga0.8N grown. The Hall measurement showed a low background carrier concentration of 7×1017 cm−3. The electron mobility was 150cm2 V−1 s−1 for the Al0.2Ga0.8N film doped to 2×1018 cm−3. The surface morphology and crystal quality were systematically examined at different growth stages. The likely mechanism for the strain relaxation and high-quality AlGaN films grown were also suggested. [Copyright &y& Elsevier]