Cultivated soybeans [Glycinemax (L.) Merr.] have various flower colours such as dark purple, purple, light purple, pink, magenta, near white and white. About one-third of the soybean accessions in the United States Department of Agriculture – Germplasm Resource Information Network (USDA-GRIN) Soybean Germplasm Collections have white flowers and are the second dominant accessions after the purple-flowered accessions. Earlier studies have shown that the w1 recessive allele of the W1 gene encoding flavonoid 3′,5′-hydroxylase produces white flowers. In the present study, we aimed to understand why the white-flowered accessions have become abundant among the cultivated soybeans and what their genetic and regional origin is. For this purpose, 99 landraces with white flowers and 39 landraces with purple flowers from eight Asian countries and Russia were analysed with regard to the nucleotide sequences of the W1 locus. We not only found that the w1 alleles of the 99 white-flowered landraces were identical to those of the white-flowered Williams 82, but also found that these w1 alleles displayed no polymorphism at all. By carrying out a phylogenetic analysis, we were able to identify a group with W1 alleles from which the w1 allele might have diverged.

This paper provides an overview of the development and application of the National Aquatic Ecological Monitoring Program (NAEMP) in Korea, which uses biological and habitat–riparian criteria for river/stream and watershed management. Development of NAEMP began in 2003, with recognition by the Korean Ministry of Environment (MOE) of the limitations of applying chemical parameters (e.g., biochemical oxygen demand (BOD)) as the principal targets of water environment management. Ecosystem health criteria under NAEMP were developed from 2003 to 2006. Candidate sites for monitoring were also screened and established across the country. NAEMP was implemented in 2007, and since then a standard protocol of nationwide monitoring based on multi-criteria has been implemented to assess the ecological condition of rivers and streams. The monitoring results indicate that many Korean rivers and streams are severely degraded, with biological conditions that are much worse than their water chemistry suggests. In 2009, 24% of rivers and streams were in classes C (Fair) and D (Poor) for BOD, but more than 71, 53, and 27% were categorized as Fair to Poor according to fish, diatom, and benthic macroinvertebrate assemblages, respectively. NAEMP is promising in that the results have already had great impacts on policy making and scientific research relevant to lotic water environment and watershed management in Korea. In the future, NAEMP results will be used to develop more aggressive regulations for the preservation and restoration of rivers/streams, riparian buffer areas and watersheds. Another future aim of the NAEMP is to develop aquatic ecological modeling based on the monitoring results.

Despite numerous previous studies, relationships between watershed land use and adjacent streams and rivers at various scales in Korea remain unclear. This study investigated the relationships between land uses and the physical, chemical, and biological characteristics of 720 sites of streams and rivers across the country. The land uses at two spatial scales, including a 1-km buffer and the base watershed management region (BWMR), were computed in a geographical information system (GIS) with a digital land use/land cover map. Characteristics of land uses at two spatial scales were then correlated with the monitored multidimensional characteristics of the streams and rivers. The results of this study indicate that land use types have significant effects on stream and river characteristics. Specifically, most characteristics were negatively correlated with the proportions of urban, rice paddy, agricultural, and bare soil areas and positively correlated with the amount of forest. The site-scale and BWMR-scale analyses suggest that BWMR land use patterns were more strongly related to ecological integrity than they were to site land use patterns. Improving our understanding of land use effects will largely depend on relating the results of site-specific studies that use similar response techniques and measures to evaluate ecological integrity. In addition, our results clearly indicate that the characteristics of streams and rivers are closely linked and that land use types differentially affect those characteristics. Thus, effective restoration and management for ecological integrity of lotic system should consider the physical, chemical, and biological factors in combination.

The mechanical properties of NiAl/Ni micro-laminated composites with highly gradient microstructure have been investigated. Two types of composites with different gradient microstructures were prepared by reaction synthesis. Intermetallics of type I and type II composites mainly consisted of Al-rich Ni0.45Al0.55 with variable thickness and Ni-rich Ni0.58Al0.42 with similar thickness, respectively. As intermetallic volume fraction increased, yield strength of type II followed the rule-of-mixture well, while that of type I deviated due to the composition variation of intermetallic phases. Fracture toughness of type II was higher than that of type I, and all showed KR curves with upward curvature by large-scale bridging. Even though the relative strength of constituent phases in intermetallic/metal laminates was not constant due to the gradient microstructure, the fracture mode transition showed similar behavior to that of metal/ceramic laminates.

Micro-tensile properties of hard and soft thin films, TiN and Au, were evaluated by directly measuring tensile strain in film tension using the micro-ESPI(electronic Speckle Pattern Interferometry) technique. Micro-tensile stress-strain curves for these films were obtained and the properties were determined. TiN thin film 1 μm thick and Au films with two different thicknesses (t=0.5 μm and 1 μm) were deposited onto the silicon wafers, respectively, and micro-tensile specimens wide 50, 100 and 200 μm were fabricated using micromachining. In-situ measurement of the micro-tensile strain during tensile loading was carried out using the subsequent strain measurement algorithm and the ESPI system developed in this study. The micro-tensile curves showed that TiN thin film was a linear-elastic material showing no plastic deformation and Au thin film was an elastic-plastic material showing significant plastic flow. Effect of the specimen dimensions on mechanical properties was examined. It was revealed that tensile strengths for both films were slightly increased with increasing specimen width. Furthermore, variations of yielding strengths for the thin film Au with change of the dimension were investigated.

A mucin coat is deposited on rabbit embryos during passage through the oviduct; rabbit blastocysts cultured from the 1-cell stage in vitro have no mucin coat. When cultured blastocysts are transferred to recipients, the lack of mucin coat might account in part for subsequent failure of pregnancy. We have investigated the possibility that mucin coat deposition is induced following transfer of in vitro 72 h-cultured blastocysts to oviducts of asynchronous or synchronous recipients. One-cell embryos were collected by flushing oviducts 19–20 h post-coitus and were cultured in vitro for 72 h until they reached the blastocyst stage. The blastocysts were transferred to the oviducts of recipients that were synchronized either with the donors (synchronous) or 1 day later than the donors (asynchronous). They were recovered after 24–48 h and the mucin coat thickness and embryo degeneration rate were measured. The degeneration rate of blastocysts recovered from uteri of synchronous recipients was higher than that from asynchronous recipients (72.2% vs 40.0%). The mucin coats around embryos recovered from oviducts of asynchronous recipients after 48 h were thicker than those from synchronous recipients. More asynchronous recipients were pregnant and gave birth to more pups than synchronous recipients. These results indicate that the oviducts of asynchronous recipients secreted more mucin around the transferred embryos, causing higher rates of implantation of the in vitro-cultured blastocysts.

Silicon nitride–Si2N2O in situ composites were prepared by hot pressing powder mixtures of α–Si3N4, 6 wt% Y2O3, 1 wt% Al2O3, and 0–12 wt% SiO2. X-ray diffraction (XRD) analysis indicated that the volume percents of Si2N2O were 0, 13, 31, and 54 for the composites prepared with 0, 4, 8, and 12 wt% SiO2, respectively. XRD results also indicated that both silicon nitride grains and Si2N2O grains were laid down perpendicular to hot pressing direction. As the volume percent of Si2N2O increased, the width and the amount of elongated silicon nitride grains decreased, but the fracture toughness increased. Young's modulus of the in situ composites decreased as the Si2N2O content was increased. The erosion rate decreased as the Si2N2O content was increased, in part, due to both the increased fracture toughness and the reduced grain size. Erosion of the composites occurred primarily due to the grain dislodgment. The sample without Si2N2O experienced micro-chipping due to transgranular fracture.

Nanocrystalline nickel oxide–yttrium-stabilized zirconia (NiO/YSZ) composite powder for the solid oxide fuel cells was prepared by solution combustion through control of pH values and contents of glycine fuel in precursor solution. A strongly acidic precursor solution with appropriate amounts of glycine fuel added increased the specific surface area of the synthesized composite powders. This results from the increased binding of metal ions and glycine under strongly acidic solution (pH = 0.5) conditions. After sintering and reducing treatment of nanocrystalline NiO/YSZ composite, the Ni/YSZ pellet showed an ideal microstructure: fine Ni particles of 3 to 5 μm were distributed uniformly, and fine micropores around Ni metal particles were formed, thus leading to an increase in the triple phase boundary area among gas, Ni and YSZ.

The degradation behavior of polarization and leakage current characteristics of sol-gel-derived (Pb,La)(Zr,Ti)O3 (PLZT) thin films, with Pt, Ir, and IrO2 top electrodes, by annealing under a 4% H2/96% N2 atmosphere were investigated. The leakage current behaviors of Pt/PLZT/Pt and IrO2/PLZT/Pt capacitors annealed at 300 °C for 20 min in 4% H2 were well consistent with the space-charge-influenced injection model proposed. However, IrO2/PLZT/Pt capacitors recovered at 700 °C for 10 min in Ar ambient after hydrogen anneal were not consistent with the proposed model because a conducting phase of IrPb was formed between the top electrode and PLZT during the recovery anneal at 700 °C in Ar ambient and modified the Schottky barrier height. The true leakage current behavior of IrO2/PLZT/Pt capacitors recovered after hydrogen forming are similar to those of Ir/PLZT/Pt capacitors without the hydrogen-forming gas anneal. The P–E loops of Pt/PLZT/Pt and Ir/PLZT/Pt capacitors showed good recovery through recovery anneal after H2 treatment. However, IrO2/PLZT/Pt capacitors depended on the recovery anneal atmosphere (Ar or O2).

(200)-oriented Pt thin films were deposited on SiO2/Si substrates by dc magnetron sputtering using Ar/O2 gas mixtures. Oxygen incorporation into Pt films changed deposition rate, resistivity, stress, and preferred orientation of the films. Increase in film resistivity and decrease in tensile stress were presumed to be the results of the incorporated oxygen into grain boundaries, while the change of preferred orientation resulted from the oxygen incorporation into the Pt lattice. The preferential growth of (200) planes with less total strain energy from the incorporated oxygen resulted in strong (200) preferred orientation in Pt films.

Highly (200)-oriented Pt films on SiO2/Si substrates were successfully prepared by a combination of a dc magnetron sputtering using Ar/O2 gas mixtures and subsequent controlled annealing. The intensity ratio of (200) to (111) planes (I200/I111) was over 200. The (200)-oriented Pt microcrystallites were less susceptible to amorphization due to their lower strain energy with oxygen incorporation than (111)-oriented ones. The controlled grain growth from the selected (200)-oriented seed microcrystallites during subsequent annealing provided a kinetic pathway where grain growth of the seed microcrystallites was predominant, while suppressing the nucleation of surface energy-driven, (111)-oriented seed microcrystallites and subsequent (111) preferred orientation.

Sputtered TiN (30–120 nm thick)/Ti (30 nm thick) films were studied as a diffusion barrier between silicon substrate and copper films. The effects of TiN thickness and the existence of a SiO2 layer between Ti and silicon substrate on the diffusion barrier property were investigated using various characterization methods. The copper diffusion barrier property of TiN/Ti was found to be affected not only by the TiN thickness, that is diffusion distance, but also by the microstructure of the TiN, which changes with the thickness of TiN film. The existence of the SiO2 layer enhanced the diffusion barrier property of TiN/Ti. This is because the SiO2 layer between Ti and Si inhibited the formation of titanium silicides, so the Ti layer was available to be used as the sacrificial diffusion barrier for copper.

Amorphous Ta-Si-N thin film was deposited by dc sputterring of Ta5Si3 target in (Ar+N2) atmosphere. The crystal structure and the thermal stability of Ta-Si-N thin films were investigated by XRD, RBS, AES, Nomarski microscope, and TEM. When the concentration of nitrogen in Ta-Si-N thin film was higher than 40 at.%, the Ta-Si-N thin film remained the amorphous state after the annealing at 1100°C for 60 min. In this case, the Cu diffusion was prevented by the amorphous Ta-Si-N thin film even if the annealing temperature increased up to 900°C for 30 min. Whereas, the Ta-Si-N thin film with nitrogen concentration less than 40 at. % was transformed from the amorphous to the polycrystalline TaSi2 phases after the annealing at 900°C for 60 min and failed to prevent the Cu diffusion after the annealing at 700°C for 30 min.

Amorphous Ta-Si-N thin film was deposited by dc sputterring of Ta5Si3 target in (Ar+N2) atmosphere. The crystal structure and the thermal stability of Ta-Si-N thin films were investigated by XRD, RBS, AES, Nomarski microscope, and TEM. When the concentration of nitrogen in Ta-Si-N thin film was higher than 40 at.%, the Ta-Si-N thin film remained the amorphous state after the annealing at 1100°C for 60 min. In this case, the Cu diffusion was prevented by the amorphous Ta-Si-N thin film even if the annealing temperature increased up to 900°C for 30 min. Whereas, the Ta-Si-N thin film with nitrogen concentration less than 40 at. % was transformed from the amorphous to the polycrystalline TaSi2 phases after the annealing at 900°C for 60 min and failed to prevent the Cu diffusion after the annealing at 700°C for 30 min.

Zirconia (ZrO2) thin films were prepared by metalorganic chemical vapor deposition (MOCVD) using ultrasonic nebulization with new source materials, Zr(OBu)4, Zr(OBu)3(acac), Zr(OBu)2(acac)2, and Zr(OBu) (acac)3. This process is a simple and economic method to prepare oxide thin films. Zr(OBu)4 was successfully reacted with acetylacetone at a molar ratio of 1: 3. Polycrystalline thin films were deposited at a substrate temperature range from 300 to 550 °C. The substitution of alkoxy radicals by acetylacetone made the deposition rate higher and insensitive to substrate temperature. The films deposited below 450 °C mostly had a monoclinic structure, and those deposited above 450 °C had a tetragonal structure. The measured optical energy band gap of zirconia film was 5.32 eV.

The substrate bias was applied during the chemical vapor deposition (CVD) process of copper in an effort to change the adsorption behaviors of the reactant. Copper films were deposited on TiN and SiO2 from Cu(hfac)(tmvs) with the substrate bias and without one. The surface morphology, the thickness, the sheet resistance and the purity of the films were investigated. When the negative substrate bias of -30 V was applied to the substrate, the deposition rate of copper increased both on TiN and SiO2. No change was observed in the chemical composition of the copper film deposited with substrate bias in comparison with that of the copper film deposited with no bias. It was calculated that Cu(hfac) has the dipole moment whose direction is from copper to hfac. Under the d. c.electric field, dipole tends to align along the poling direction. Resulting from the overlapping population (OP) value analysis, the improvement of deposition rate under negative substrate bias was explained due to the adsorption of copper atom in Cu(hfac) species directly onto the substrate by the electric field applied between the substrate and the gas showerhead.

Pt thin films were deposited by a DC magnetron sputtering with Ar/O2 gas mixtures. Due to the oxygen incorporation into the Pt films, deposition rate and resistivity of as-deposited Pt thin films increased with oxygen fraction in the sputtering gas. No peaks from crystalline Pt oxides were observed by x-ray diffraction (XRD) and excessive oxygen incorporation into Pt lead to an amorphous Pt oxide formation. More oxygen could be incorporated in the Pt thin films deposited at lower temperatures and at higher total pressures. Incorporated oxygen was completely removed after an annealing at 800 °C for an hour in air ambient, as the resistivity of the Pt thin films recovered their bulk resistivity values. Tensile stress of the Pt films decreased with oxygen incorporation, and approached a saturation level at high resistivity of the films, presumably due to the formation of amorphous Pt oxides.