Physicochemical Properties and Eating Qualities of Milled Rice from Different Korean Elite Rice Varieties

Physicochemical properties and palatability of rice from six elite varieties in Korea (Chucheongbyeo, Saechucheongbyeo, Mihyangbyeo, Hitomebore, Nampyeongbyeo, and Ilpumbyeo) were analyzed. All samples, which contained 17–18 g/100 g rice starch amylose, belong to low-amylose rice group. Hitomebore variety showed abundant amount of essential amino acids, highest palatability score (82.9), and lowest mineral content. The rice samples contained relatively similar concentrations of saturated (21–24 g/100 g rice) and unsaturated (75–78 g/100 g rice) fatty acids. Mihyangbyeo variety exhibited the highest amount of protein (8.10 g/100 g rice), sugar content, and pasting temperature (82.75°C) and time (3.78 min), but lowest viscosity values. Ribose, rhamnose, and potassium were found to have negative correlations with palatability and breakdown viscosity, indicating that gelatinization characteristics could also be used in evaluating the eating quality of rice. Results of this study could assist plant breeders in developing rice varieties with improved genetic traits and high eating quality.     

Simulation of κ-Carbide Precipitation Kinetics in Aged Low-Density Fe–Mn–Al–C Steels and Its Effects on Strengthening

Fe–Al–Mn–C alloy systems are low-density austenite-based steels that show excellent mechanical properties. After aging such steels at adequate temperatures for adequate time, nano-scale precipitates such as κ-carbide form, which have profound effects on the mechanical properties. Therefore, it is important to predict the amount and size of the generated κ-carbide precipitates in order to control the mechanical properties of low-density steels. In this study, the microstructure and mechanical properties of aged low-density austenitic steel were characterized. Thermo-kinetic simulations of the aging process were used to predict the size and phase fraction of κ-carbide after different aging periods, and these results were validated by comparison with experimental data derived from dark-field transmission electron microscopy images. Based on these results, models for precipitation strengthening based on different mechanisms were assessed. The measured increase in the strength of aged specimens was compared with that calculated from the models to determine the exact precipitation strengthening mechanism.     

Prevalence, antibiotic susceptibility, and virulence factors of Yersinia enterocolitica and related species from ready-to-eat vegetables available in Korea

A total of 673 ready-to-eat vegetable samples were collected in Korea from 2001 to 2002 and analyzed for the presence of Yersinia spp. We analyzed biotypes, serotypes, and susceptibility to 12 antibiotics and tested for virulence genes of pathogenic Yersinia enterocolitica isolates by PCR assay. Among the samples, 27 (4.0%) were found to be contaminated with Yersinia spp. Among the 27 strains of Yersinia spp. isolates, 18 strains (66.7%) of Y. enterocolitica, 5 strains (18.5%) of Y. frederiksenii, 3 strains (11.1%) of Y. intermedia, and 1 strain (3.7%) of Y. kristensenii were identified. According to the serotypes of Y. enterocolitica isolates, O:3 (11.1%) and O:5 (11.1%) were the most predominant, followed by O:8 (5.6%) and others (72.2%). For biotypes of Y. enterocolitica isolates, 1A (77.8%) was the most predominant, followed by 3B (11.1%), 3 (5.6%), and 5A (5.6%). Also, an antibiotic susceptibility test showed that Y. enterocolitica isolates were very susceptible to the antibiotics tested but highly resistant to ampicillin (94%), cephalothin (100%), and carbenicillin (83%). PCR assays with specific primers derived from yst and ail genes of Y. enterocolitica were applied to confirm the presence of pathogenic Y. enterocolitica. Among the 18 strains of Y. enterocolitica isolates, only 3 strains (O:3/1A, UT/3B, and UT/1A isolated from Chinese cabbage, onion, and spinach, respectively) were shown to have a virulence gene.     

Effects of tomato ketchup and tomato paste extract on hepatic lipid accumulation and adipogenesis

Food Science and Biotechnology - Tomatoes include high levels of lycopene, which is a potent antioxidative, hypolipidemic, and antidiabetic phytochemical. The intake of lycopene is associated with...     

Small molecule interlayer for solution processed phosphorescent organic light emitting device

Using a 4,4′,4′′-tris(N-carbazolyl)-triphenylamine (TCTA) small molecule interlayer, we have fabricated efficient green phosphorescent organic light emitting devices by solution process. Significantly a low driving voltage of 3.0 V to reach a luminance of 1000 cd/m² is reported in this device. The maximum current and power efficiency values of 27.2 cd/A and 17.8 lm/W with TCTA interlayer (thickness 30 nm) and 33.7 cd/A and 19.6 lm/W with 40 nm thick interlayer are demonstrated, respectively. Results reveal a way to fabricate the phosphorescent organic light emitting device using TCTA small molecule interlayer by solution process, promising for efficient and simple manufacturing.     

Dispersion Improvement of Platinum Catalysts Supported on Silica, Silica-Alumina and Alumina by Titania Incorporation and pH Adjustment

Platinum catalysts supported on silica, silica-alumina and alumina supports were prepared using four different cationic and anionic platinum precursors in order to examine the contribution of the precursors and supports to the platinum dispersion. The pH adjustment of the precursor suspension to obtain an opposing surface charge of the support to that on the platinum precursor ions considerably improved the platinum dispersion by strengthening their adsorption on the support. However, exceptional platinum dispersion was achieved, regardless of the precursor and support, by simultaneous pH adjustment and titania incorporation on the supports. The increase in the interaction between the platinum precursor and the titania-incorporated support raised the dispersion and stability of the platinum catalysts with high-loading, even after reduction at 400 °C. The physico-chemical states of platinum and titanium were investigated by XRD, TEM, XAFS spectroscopy and CO adsorption technique. The platinum catalysts supported on the titania-incorporated supports with pH adjustment exhibited highly dispersed platinum particles ranging in size from 1 to 3 nm. They also exhibited high catalytic activity in the oxidation of carbon monoxide because of its incorporated titania and partially oxidized, small platinum particles.     

In vitro apatite formation on organic–inorganic hybrids in the CaO–SiO<Subscript>2</Subscript>–PO<Subscript>5/2</Subscript>–poly(tetramethylene oxide) system

The osteoconduction potential of artificial materials is usually evaluated in vitro by apatite formation in a simulated body fluid (SBF) proposed by Kokubo and his colleagues. This paper reports the compositional dependence of apatite formation on organic–inorganic hybrids in the CaO–SiO₂–PO_5/2–poly(tetramethylene oxide) system, initiated from tetraethoxysilane (TEOS), triethyl phosphate (OP(OEt)₃), calcium chloride (CaCl₂) and poly(tetramethylene oxide)(PTMO) modified with alkoxysilane. Formation of an apatite layer was observed on the surface of the organic–inorganic hybrids with molar ratios of TEOS/OP(OEt)₃ ranging from 100/0 to 20/80. The rate of apatite formation remarkably decreased when the hybrids were synthesized with TEOS/OP(OEt)₃ ratios of 40/60 or less. Hybrids without TEOS showed no apatite formation in SBF for up to 14 days. Addition of small amounts of OP(OEt)₃ to TEOS in the hybrids led to the high dissolution of calcium and silicate, while addition of large amounts of OP(OEt)₃ decreased the dissolution of calcium and silicate ions and resulted in reduced apatite formation regardless of the dissolution of phosphate ions from the hybrids.     

Rare-Earth Permanent Magnet SmCo5 for Chiral Interfacial Spin-Orbitronics

Interfacially asymmetric magnetic multilayers made of heavy metal/ferromagnet have attracted considerable attention in the spintronics community for accommodating spin-orbit torques (SOTs) and meanwhile for hosting chiral spin textures. In these multilayers, the accompanied interfacial Dzyaloshinskii–Moriya interaction (iDMI) permits the formation of Néel-type spin textures. While significant progresses have been made in Co, CoFeB, Co₂FeAl, CoFeGd based multilayers, it would be intriguing to identify new magnetic multilayers that could enable spin-torque controllability and meanwhile host nanoscale skyrmions. In this report, first, thin films made of permanent magnet SmCo₅ with perpendicular magnetic anisotropy are synthesized, in which the deterministic SOT switching, enabled by the spin Hall effect, in Pt/SmCo₅/Ta trilayer is demonstrated. Further, the stabilization of room-temperature skyrmions with diameters ≈100 nm in [Pt/SmCo₅/Ta]₁₅, together with a skyrmionium-like spin texture in [Pt/SmCo₅/Ir]₁₅ multilayers is shown. Based on the material specific parameters, micromagnetic simulations are also carried out. The results confirm the presence of chiral spin textures in this new material family. Through interfacial engineering, the results thus demonstrate that rare earth permanent magnets could be a new platform for studying interfacial chiral spintronics.     

Effective Model for Prediction of N2O and NH3 Formation During the Regeneration of NO x Storage Catalyst

In this paper we propose an effective global kinetic model that allows prediction of N₂O and NH₃ formation during the reduction of stored NO _x in dependence on the composition of the rich mixture (H₂/CO/C₃H₆), actual operating temperature, and length of regeneration period. A bench flow reactor equipped with a high-speed FTIR was used to measure dynamic evolution of gas components during periodic lean/rich operation of a fully formulated NSRC catalyst (PtPdRh/Ba/Ce–Zr/Mg–Al/Al₂O₃).