• The Journal of the Petrological Society of Korea
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• v.27 no.2
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• pp.97-104
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• 2018

The U-Pb isotopic and rare earth element compositions of zircon were measured using a SHRIMP from a tonalitic gneiss sample DE43 in Daeijak Island, central Korea. Zircon crystals, up to ${\sim}300{\mu}m$ in diameter, rarely contain thin overgrowth rims. In contrast to Paleoproterozoic cores, the $^{206}Pb/^{238}U$ ages of $256{\pm}23Ma(1{\sigma})$, and $221{\pm}7Ma(1{\sigma})$ were yielded from two spot analyses on the overgrowth rims of zircon. The rims are geochemically characterized by low Th/U ratios (<0.01) and strongly depleted light rare earth elements. The Permian-Triassic apparent ages of zircon are consistent with the $^{208}Pb/^{232}Th$ ages dated from allanite ($227{\pm}7Ma(t{\sigma})$) in the same sample within uncertainties, indicating an equilibrium growth of allanite and zircon at ~227 Ma. On the other hand, the younger $^{208}Pb/^{232}Th$ and $^{206}Pb/^{238}U$ ages ($213{\pm}4Ma(t{\sigma})$ and $186{\pm}9Ma(t{\sigma})$, respectively) of allanite may result from Pb loss due to the infiltration of alkali fluids from Late Triassic and Jurassic granitoids nearby.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.409-414
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• 2020

In this study, we conducted a physiochemical property analysis using commercial faba bean flour (CFBF), faba bean flour (FBF), and faba bean starch (FBS). We observed that the FBS granules were elliptical and cracked on the surface. Moreover, FBS showed significantly lower solubility and apparent viscosity than FBF and CFBF. With respect to the pasting properties, FBS exhibited a peak viscosity of 1349.3 cP at 94.8℃ and a breakdown of 42.7 cP, whereas FBF and CFBF displayed no pasting properties. The FBS gelatinization enthalpy (12.9 J/g) was relatively high compared with the values obtained for FBF and CFBF (5.9 and 4.6 J/g, respectively). The FBS X-ray diffraction patterns showed a C-type pattern with peaks at diffraction angle (2θ) of 5.9°, 15.2°, 17.3°, and 23.1°, which were the same in FBF and CFBF with relatively low peak intensity. These results represent basic data for using faba bean as a food material.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.2
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• pp.68-74
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• 2005

The electrical arc furnace (EAF) classified as a special waste contains many flux components producing melts during a sintering process, so it decreases the sintering temperature and improves the mechanical properties of specimens. Increasing dust content in a clay-dust system brick, however, may cause the fraction defective higher due to the excessive liquid produced. To control the liquid behavior produced during sintering process for the clay-dust system specimens, the $Al_2O_3$ was added and the physical properties were analyzed. The microstructure for the clay-dust system body sintered with $Al_2O_3$ became homogeneous and the overall size of pores decreased. Adding $Al_2O_3$ to clay-dust system body increased the mechanical properties and the temperature of maximum strength increased as much as $50^{\circ}C$, and the apparent density increased and the absorption decreased. The mullite ($3Al_2O_3{\cdot}2SiO_2$) was produced during sintering process by reaction of $Al_2O_3$ and $SiO_2$ which could participate to liquid-producing-process and the viscosity of melts increased which was proved by measuring a critical viscosity temperature (Tcv) therefore, the refractoriness of specimens were improved to lower the fraction defective.

• KSBB Journal
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• v.18 no.5
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• pp.412-417
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• 2003

We first investigated basic characteristics of reticulated polyurethane (PU) foams as microbial carriers. In general, the specific surface area of PU foams increases with respect to decreasing pore sizes. However, the number of microbes adhered on the unit surface of reticulated PU foams decreases with respect to decreasing pore sizes. Thus, as a result of totally considering all effects such as apparent density, hydrolysis rate, and adhesion, we can know that PU foams with 45 PPI is the most appropriate microbial carrier. In this study, we can also investigate the effect of various physico-chemical surface treatments on the adhesion of microbes on the surface of PU foams. We used a chitosan treatment, a PEI (Polyethylene Imine) treatment, a xanthane treatment and a plasma treatment. As a result of comparing all surface treatments, the plasma surface treatment was the best.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.774-778
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• 1999

Tee yields, physical properties and gel formation abilities or hot-water extractable material (HWEM) and water-soluble alginate (WSA) extracted from Laminaria japonica were estimated and compared with those of the alginate (ASA) extracted with alkali solution in the routine procedure. The contents of HWEM, WSA and ASA in Laminaria japonica were 8.3, 2.5 and $19.1\%$, respectively. The HWEM and WSA had no gel formation ability, whereas the ASA had a good gol formation ability. The HWEM and WSA were almost not viscous even in $1.5\%$ of the sample solution, whereas the ASA was very highly viscous in above $0.5\%$ of sample solution. The melting points of $1\%$ solution of HWEM, WSA and ASA sample were 31, 24 and $14^{\circ}C$, respectively. The solubility at melting point of each samples varied from 2.3 to 2.6 g/100 g water, and a few differences were observed.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.499-505
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• 1987

The functional properties of lupin seed protein concentrate (LPC) were examined and compared to those of soybean protein isolate (SPI) and Na-caseinate. LPC-50, of which protein level was 50%, was prepared by a two phase solvent (hexane: alcohol: water= 10:7:3) extraction method. LPC-70 was made from LPC-50 by removing the fractions solubilized by carbohydrate decomposing enzymes. The solubilities of LPC-50 and LPC-70 were similar to that of of SPI but slightly higher at pH 4-5, and less susceptible to the added salt. The apparent viscosity of LPC increased exponentially as the concentration increased over 6% level, and the change was similar to that of Na-caseinate. LPC showed strong pseudoplastic non-Newtonean flow behavior, which was similar to that of SPI The emulsifying capasity of LPC-70 was similar to that of SPI when salt was added. The foaming capacity of LPC was comparable to that of SPI. LPC showed high oil and water absorption capacities, which increased as the protein level was elevated. LPC-70 showed the highest oil absorption capacity of all the samples tested.

• Journal of Aquaculture
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• v.13 no.1
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• pp.87-99
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• 2000

Field survey on the variational characteristics of water quality and chlorophyll a concentraion were carried out at the 25 stations for four seasons in Kogum-sudo(Straits) southern coast of Korean Peninsula from Feburuary to October in 1993. We made an analysis on biological factor as chlorophyll a concentraion as well as physicio-chemical factors such as water temperature salinity sigma-t transparency dissolved oxygen(DO) chemical oxygen demand(COD) nutrients (ammonia, nitrite, nitrate, phosphate, and silicate) N/P ratio and suspended solid(SS). The waters in the Kogum-sudo were not stratified due to the tidal mixing. And the high productivity in photic layer were supported by high nutrients concentration from bottom waters. The high concen-trations of suspended solid in straits had a bad influence upon marine biology of nature and cultivations. In Kogum-sudo had a sufficient nutrients for primary productivity during a year. Especially phosphate and inorganic nitrogen were high the other side silicate was very low. The source of nutrients supply depend on rather mineralization of organic matters and input of seawater from outside than input of freshwaters from lands. Phytoplankton biomass as measured by chlorphyll a concentratiion was very high all the year round and it was controlled by the combination o f several environmental factors especially of phosphate in summer and dissolved nitrogen in other seasons.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.161-165
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• 2001

The dietary fiber was extracted from apple pomace with various concentrations of acidic, alkaline solvents and water in $24.4{\sim}29.3%$ yield. The extractions of water-soluble dietary fiber with acidic(6.85%) and alkaline solvent(6.55%) were more effective than the water extraction(6.0%). The higher extraction yield was obtained with increased concentration of acidic or alkaline solvents. The content of galacturonic acid was higher in the order, 0.01 M HCl(77.5%)>0.05 M HCl(76.8%)>$H_2O(76.1%)$>0.05 M NaOH(73.8%)> 0.01 M NaOH(69.0%) and the extraction with acidic solvent showed the highest pectin yield. The color value increased by extraction with solvent in higher concentration. And at equal concentration, the color value of alkaline extract was higher than that of acidic exctract. There was no relationship between the color value and the extraction yield of dietary fiber. In the investigation on the rheological properties, the shear stress increased in proportion to galacturonic acid contents. While water-soluble dietary fiber extracted with acid and water represented Newtonian rheological properties, the alkaline extract was inclined to have converting property from pseudoplastic to Bingham pseudoplastic with increment of alkaline concentration. In the studies on the time-dependence of apparent viscosity, the thixotropic property with hysteresis loop was observed in alkaline extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1195-1201
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• 2005

This study has investigated the bioavailability of calcium in eggshell powder (ESP) fortified ramen. Wean-ling SD rats were maintained for 2 weeks on 0.05$\%$ low calcium diet then assigned randomly to one of 5 groups. Animals were provided for 4 weeks one of 3 different experimental diets containing 0.15$\%$ calcium as $CaCo_{3}$, NFDM, or ESP fortified ramen. Two control groups were fed either 0.05$\%$ calcium or general ramen containing 0.08$\%$ calcium. The body weight, diet intake, food efficiency ratio (FER), bone growth, calcium contents of bones, and apparent absorption were measured. Experimental results show that regardless of calcium sources 0.15$\%$ calcium groups increased body weight, weight and length, calcium content, and the strength of two bones (tibia and femur) significantly compared to 0.05$\%$ calcium group. The apparent absorption rate of calcium also showed similar results supporting the bioavailability of ESP fortified ramen is not inferior to either NFDM or $CaCO_{3}cdot$ The results indicate that ESP fortified ramen is a proper mediate for calcium fortification in Korea.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.276-282
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• 2004

Barley flakes were developed by extrusion cooking using broken kernels, by-products of the barley pearling process. Broken kernels from both non-waxy and waxy barley broken kernels were sufficiently gelatinized at the barrel temperature of over $100^{\circ}C$ and the moisture content of broken kernels of over 35%. Cutting and flaking roll separating properties of pellets prepared from non-waxy barley broken kernels were better than those of waxy barley broken kernels. Characteristics of pellets prepared by extrusion cooking in different mixing ratios of non-waxy and waxy barley broken kernels were investigated. As the mixing ratio of waxy barley broken kernels increased, RVA peak viscosity, apparent viscosity, and yield stress of prepared pellets decreased, while flow behavior index increased. As the mixing ratio of waxy barley broken kernels increased, compressive strength and bulk density of deep-fat fried flakes drastically decreased, and the size of air cells on cross-section increased, and thickness of cell-constituting bodies decreased. Sensory evaluation results showed that acceptability for texture and taste of flakes inclosed as the mixing ratio of waxy barley broken kernels increased, and optimum mixing level of waxy barley broken kernels appeared to be 30-40%.