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An X-ray diffraction pattern (XRD) showed that GaN nanorods grown on Si(111) substrates were preferentially oriented along the [0001] direction. The transmission electron microscopy (TEM) images showed that the side facet planes of the tip region for the GaN nanorods consisted of {1100} and {1102} planes. The disordered nuclei of the GaN nanorods produced a two-dimensional thin-film layer near the GaN/Si(111) interfacial region. The relation between the microstructural properties and the geometry factors of the tip region for GaN nanorods formed on Si(111) substrates is described on the basis of the XRD and TEM results.

X-ray diffraction patterns, scanning electron microscopy images, and transmission electron microscopy (TEM) images showed that one-dimensional GaN nanorods grown on Si (1 1 1) substarates by using hydride vapor phase epitaxy had crystalline wurzite structures and were preferentially oriented along the [0 0 0 1] direction. The high-resolution TEM (HRTEM) images showed that the side facet planes of the tip region for the GaN nanorods consisted of {1¯ 1 0 0}, {1¯ 1 0 2}, and {1¯ 1 0 3} planes. The structural properties of the GaN nanorods were significantly affected by the gas-mixing and the substrate temperatures in the final growth zone.

Scanning electron microscopy (SEM) images, transmission electron microscopy (TEM) images, and selected-area electron diffraction (SAED) patterns showed that vertically well aligned GaN nanorods with c-axis-oriented crystalline wurzite structures were grown on Si(1 1 1) substrates by using hydride vapor phase epitaxy. The high-resolution TEM (HRTEM) images showed that the crystallized GaN nanorods contained very few defects and that they were consisted of { 1 ¯ 1 0 0 } , {0 0 0 1}, and { { 1 ¯ 1 0 N } } facets. The formation mechanisms for the GaN nanorods grown on Si(1 1 1) substrates are described on the basis of the SEM, TEM, SAED pattern, and HRTEM results.

X-ray diffraction (XRD) patterns, field-emission scanning electron microscopy (FESEM) images, transmission electron microscopy (TEM) images, and selected area electron diffraction pattern (SADP) images showed that one-dimensional GaN nanorods with c -axis-oriented single-crystalline wurzite structures were grown on Si (1 1 1) substrates by using improved hydride vapor phase epitaxy. The high-resolution TEM (HRTEM) images showed that the crystallized GaN nanorods contained very few defects. The atomic arrangements for the GaN nanorods grown on the Si (1 1 1) substrates are described on the basis of the XRD, the TEM, the SADP, and the HRTEM results.

Continuous measurements of trace elements in size-segregated aerosols were performed by X-ray fluorescence analysis in order to assess the transport of natural and anthropogenic aerosol sources to Gosan site in springtime 2002. Various aerosol elemental components (such as Al, Ca, Si, K, Ti, and Mn) had low enrichment factors close to one and exhibited a similar temporal variation in coarse particle range (2.5–12 μm) indicating the dominant influence of soil dust. On the other hand, in the fine particle size range (0.09–2.5 μm), several anthropogenic elements in ambient particles (such as As, Se, Zn, Pb, and Cu) revealed high enrichment (100 Factor analysis was conducted with the size- and time-resolved aerosol composition data in order to identify anthropogenic sources of aerosols during non-Asian dust (NAD) period. As a result, it was found that the coarse particles were mainly influenced by soil, seasalt, coal combustion, and metallurgical emission and fine particles were significantly attributed to several anthropogenic sources, such as oil combustion, nonferrous metal source, and municipal incineration. Especially, submicron particles (0.09–0.56 μm) were further impacted by motor vehicles and field burning emissions in addition to those sources.

PM2.5 fine particles were collected at four sites in Northeast Asia, Beijing, Gwangju, Kyoto, and Ulaan-Battor, during an intensive sampling period of 23 July–2 August 2002, within the framework of the Asia-Pacific Network for Global Change Research (APN) project. The carbonaceous species, organic carbon (OC) and elemental carbon (EC), in the PM2.5 samples were analyzed by the selective thermal manganese dioxide oxidation method. The average PM2.5 mass concentrations were measured to be 144.9, 17.1, 37.9 and 17.4 μgm−3 at Beijing, Gwangju, Kyoto and Ulaan-Battor, respectively. The average OC and EC concentrations were 12.4 and 5.4 μgm−3 for Beijing, 1.4 and 0.3 μgm−3 for Gwangju, 5.0 and 1.3 μgm−3 for Kyoto and 2.3 and 0.4 μgm−3 for Ulaan-Battor. Average OC/EC ratio was computed to be 2.4, 4.2, 5.0 and 6.6 for Beijing, Gwangju, Kyoto and Ulaan-Battor, respectively. Source–receptor relationships of fine carbonaceous particles were investigated by air mass back-trajectories. The results indicated that organic carbons at Beijing are mainly from primary organic local sources.

The objective of this study was to prepare the edible composite films using high-amylose corn starch (HACS) and corn zein and to determine their physical properties. HACS was gelatinized using the specially designed high-pressure container. HACS film containing 20 g sorbitol/100 g as a plasticizer had suitable physical properties. The HACS film coated with corn zein containing 20 g oleic acid/100 g had moderate physical properties and barrier properties.

Tris-(8-hydroxyquinoline) aluminum (Alq3) films have been grown on silicon substrates by several techniques: neutral-cluster-beam deposition; thermal evaporation; and ionized-cluster-beam deposition technique. The films were characterized by low angle X-ray reflectivity, atomic force microscopy, Fourier transformed infrared (FTIR) spectroscopy and photoluminescence. According to the FTIR spectroscopy measurement, the spectra of all the Alq3 samples show almost the same signals of atomic binding regardless of the process conditions. However, the photoluminescence intensities of the films are different. When all the films are adjusted to the same thickness, neutral-cluster-beam deposition films show more intense photoluminescence than the thermal-evaporated ones, while ionized-cluster-beam deposition samples are found to be inferior in intensity. Since the photoluminescence intensity of the 8-hydroxyquinoline aluminum layers is one of the important factors for the performance of organic light emitting devices, the neutral-cluster-beam deposition seems to be a promising method for the film deposition of organic electroluminescence materials.

Activity-guided fractionation of the methanol extract of Vitis vinifera bark led to the isolation of epsilon-viniferin, ampelopcin A, vitisin A and vitisin B. Vitisin A and vitisin B showed a remarkable inhibitory activity against 3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA) reductase with IC50 value of 42.1 microM and 23.9 microM, respectively.