Synthesis and characterization of metallic Pd embedded TiO2 nanoparticles by reverse micelle and sol-gel processing

This research was financially supported by the Ministry of Education, Science Technology(MEST) and Korea Industrial Technology Foundation(KOTEF) through the Human Resource Training Project for Regional Innovation.     

Lubrication Property of Magnetorheological Fluid With Nano-Silica Additives Under Magnetic Field

Magnetorheological(MR)fluid is colloidal suspension and stiffens into semi-solid when subjected to a magnetic field.In order to investigate the effect of magnetic field on lubrication property of MR fluid with nano-silica additives,a pin-on-disc tribometer is used to carry out friction and wear experiment of steel under the magnetic field.The MR fluids with different additive concentrations are prepared and their theological properties are examined via a rotational rheometer.Different lubrication performance of the MR fluid with nano-silica additives with and without magnetic field is presented.In addition,through observing the morphology and analyzing the elemental composition of the worn surfaces,the effects of additives on the lubrication property are investigated.     

Effect of aging treatment on irradiation-induced segregation of high Mn-Cr steel

To investigate the effect of aging treatment on irradiation-induced segregation of high Mn-Cr steel, specimens for electron-beam irradiation were prepared from the high Mn-Cr austenitic steel which was solution treated at 1 373 K for 1 h and aging treated at 573 K for 1 000 h, respectively. The electron-beam irradiation was performed at 573 K up to doses of 5.4 dpa in a 1 250 kV HVEM and irradiation-induced segregation analyses were carried out by an EDX in a 200 kV FE-TEM. The results show that void formation is not observed in both solution treated and aging treated ones. The amount of Cr segregation at the grain boundary decreases in the aged one; however, that of Mn is not changed in solution treated one.     

EVALUATION OF YUKWA (A KOREAN OIL-PUFFED RICE SNACK) EXPANSION WITH INCREASES IN WATER-STEEPING DURATION OF WAXY RICE USING IMAGE ANALYSIS

Abstract Yukwa, a Korean oil-puffed rice snack with a soft texture, is currently being manufactured primarily by traditional methods. The water-steeping time of the milled waxy rice is an important factor because it has a great effect on the product quality. The expansion rates related to water-steeping durations, which are indices of Yukwa quality, were quantitatively evaluated using image analysis. The longer the water-steeping time was, the higher were the expansion parameters of the Yukwa . When the waxy rice was water-soaked over 6 days, the expansion rate of the Yukwa showed a statistically significant increase. Using these expansion rates, the diameter and diameter-implicit parameters were statistically modeled with respect to the moisture content of the rice at P 0.01. Hedonic sensory evaluation for Yukwa showed that the longer raw waxy rice was water-steeped. The better quality was due to high expansion.     

EFFECTS OF SESAME LIGNAN EXTRACT ON LINOLEIC ACID, LIPID OXIDATION, COLOR AND TEXTURAL PROPERTIES OF GROUND PORK, AND SAUSAGE PRODUCTS

Sesame lignan extract was prepared from roasted sesame oil and added at 0.02, 0.05, 0.10 and 0.20% (w/w) to linoleic acid and ground pork products. Cooked ground pork containing more than 0.02% of lignan extract showed TBA values lower than those containing butylated hydroxyanisole (BHA) during storage. Sausages containing 0.05% of lignan extract had lower thiobarbituric acid (TBA) values when stored at 4C for 14 days; they also showed higher CIE color values than the control meat sample (P < 0.05). There were no differences in textural properties such as hardness, cohesiveness and chewiness between the control and the sausages containing lignan extract when determined by Instron Testing Machine. Thus, lignan extract prepared from roasted sesame oils was highly antioxidative when used in cooked ground pork at > 0.02% or in sausages at > 0.05%.     

STABILIZATION OF GROUND GARLIC COLOR BY CYSTEINE, ASCORBIC ACID, TRISODIUM PHOSPHATE AND SODIUM METABISULFITE

Various organic and inorganic compounds at different concentrations were added to ground garlic as a means of controlling changes in color. Among the compounds tested, cysteine (C), ascorbic acid (A), sodium metabisulfite (S) and trisodium phosphate (P) were found effective in preventing a change in color towards greening. When these compounds were mixed at 0.1 M level, their binary mixtures (CS, AS, SP, AC) and ternary/quaternary mixtures (CAP, CAS, CSP, CASP) turned out to be even more effective for sustaining the original color values (L = 45, a = -2, b = 10) of ground garlic. Although the controlling effect was somewhat decreased with a reduction in mixture concentration from 0.1 to 0.03 M, the majority of mixtures (CS, SP, CAP, CAS, CSP and CASP) still maintained their effectiveness in color control.     

CALCIUM CHLORIDE EFFECTS ON TBA VALUES OF COOKED MEAT

Ground chicken breast and beef top round (semimembranosus) muscles were treated with CaCl₂ (0.05, 0.10, 0.15, and 0.20% on final sample weight basis) and cooked to an internal temperature of 80C. Cooked samples were aerobically stored at 4C for 0 or 4 days and analyzed for 2-thiobarbituric acid (TBA)-reactive substances. Results indicated that CaCl₂ can either inhibit or accelerate lipid oxidation in cooked meat depending on its concentration/meat animal species. TBA values of chicken samples were decreased by CaCl₂ used at ≥ 0.1% of final weight. However, only beef samples treated with the highest CaCl₂ level (0.20%) tended to have lower TBA values when compared to control samples (treated with deionized water only). CaCl₂ used at low levels (0.05% for chicken and ≤0.15% for beef) tended to elevate cooked meat TBA values.     

EM 3D contour maps provide protein assembly at the nanoscale within the neuronal porosome complex

The neuronal porosome complex, the secretory machinery at the plasma membrane of nerve terminals, is a 12–17‐nm cup‐shaped lipoprotein structure possessing a central plug. Since the porosome is a membrane associated, multi‐protein complex measuring >650 kD, it has precluded generation of 3D crystals for x‐ray diffraction studies, nor structural analysis at the atomic level using solution magnetic resonance spectroscopy. These limitations were partially overcome in the current studies, furthering our understanding of the porosome structure. Using atomic force microscopy, electron microscopy and electron density and 3D contour mapping, finally provides at the nanoscale, the structure and assembly of proteins within the neuronal porosome complex. Results from this study demonstrate a set of eight protein units lining the porosome cup, each connected via spoke‐like elements to a central plug region within the structure. The isolation of intact porosomes for near‐atomic resolution using cryo‐electron diffraction measurements, is finally possible.