• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.2
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• pp.85-93
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• 2013

This study has been carried out to elucidate the characteristics of the dissolution for Thermal Decomposed Solid Waste of uranium-bearing sludge (TDSW), the removal of impurities by an alkalization in a nitric acid dissolving solution of TDSW, and the selective removal (/recovery) of uranium by an acidification in an carbonate alkali solution, respectively. TDSW generated by thermal decomposition of U-bearing sludge which was produced in the uranium conversion plant operation, was stored in KAERI as a solid-powder type. It is found that the dissolution of TDSW is more effective in nitric acid dissolution than oxidative-dissolution with carbonate. At 1 M nitric acid solution, TDSW was undissolved about 30wt% as a solid residue, and uranium contained in TDSW was dissolved more than 99%. In order to the alkalization for the nitric acid dissolving solution of TDSW, carbonate alkalization is more effective with respect to remove the impurities. At the carbonate alkali solution controlled to about 9 of pH, Al, Ca, Fe and Zn co-dissolved with U in dissolution step was removed about $98{\pm}1%$. On the other hand, U could be recovered more than 99% by an acidification at pH about 3 in a carbonate alkali solution, which was nearly removed the impurities, adding 0.5M $H_2O_2$. It was found that uranium could be selectively recovered (/removed) from TDSW.

• Journal of the Mineralogical Society of Korea
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• v.24 no.4
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• pp.253-263
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• 2011

Mineralogical characteristics of garnierite ores from the Nakety, Kouaoua, and Ouaco Ni laterite deposits in New Caledonia are investigated using optical microscopy, powder X-ray diffractometer, and electron proble microanalyzer. Green garnierite ores have colloform, cellular, and boxwork texture, which are formed by precipitation under low temperature surface environment. They are mainly composed of Ni-bearing talc~willemseite series mineral and partly of lizardite. In Ni-bearing talc~willemseite series mineral, NiO contents are Ouaco (average 40.63%), Nakety (average 28.58%), and Kouaoua (average 24.90%), in descending order. Ni atomic percentage replacing Mg in octahedral site are 43.5~85.0%. Dark brown garnierite ores show cellular or boxwork texture, and consist of lizardite~Ni lizardite with some Ni-bearing talc~willemseite series mineral. Ni contents in lizardite~Ni lizardite are 1.14~4.06 wt. % and Ni atomic percentage replacing Mg in octahedral site 1.7~6.8%. Low NiO content in dark brown garnierite attributes to high Fe content replacing Mg in octahedral site.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.5
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• pp.902-910
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• 2015

This study evaluated the qualitative properties of burdock (Arctium lappa L) peels as food material. Proximate composition, sweetness, pH, total acidity, mineral, fatty acid, free sugar, and organic acid contents of preprocessed burdock were measured. Crude ash, protein, fat, and total dietary fiber contents of non-peeled treated lotus roots were higher than those of peeled treated lotus roots (p<0.05). $^{\circ}Bx$, pH, and total acidity were not different in the peeling process. Redness and yellowness of lotus roots were reduced by the peeling process, whereas lightness increased (p<0.05). The mineral contents of Ca, K, Fe, and P were higher in non-peeled lotus roots, whereas non-peeled treated lotus root showed higher K contents (p<0.05). Maltose content was not significantly different, whereas fructose, sucrose and maltose contents were significantly different. Total organic acid contents were higher in non-peeled lotus roots (p<0.01). However total free amino acid contents were higher in peeled lotus roots (p<0.01).

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.4
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• pp.542-550
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• 2016

This study was carried out to investigate the optimal processing conditions for odor removal and maximal antioxidant effects of oyster (Crassostrea gigas) hydrolysate. The optimal hydrolysis conditions were 3.3% neutrase as the protease, $50^{\circ}C$ as the hydrolysis temperature, and 8.3 h as the hydrolysis time. Fish odor of enzymatic oyster hydrolysate was greatly reduced during Saccharomyces cerevisiae fermentation at $24^{\circ}C$ with 0.5% glucose. The protein content of the fermentation product from oyster hydrolysate powder was 25.7%, which contained the major amino acids Glu, Asp, Lys, Arg, Gly, and Ala, whereas Leu, Ala, Phe, Val, and Tau were abundant free amino acids. The important minor minerals were Zn and Fe. Toxicity against Chang cells was not observed in the fermentation product from the oyster hydrolysate up to $200{\mu}g/mL$. The results suggest that fermentation with S. cerevisiae could reduce the fish odor of enzymatic oyster hydrolysate. The hydrolysate has potential application as a food ingredients and nutraceutical.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.353-358
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• 2012

This study was carried out to evaluate antioxidant and anticancer activity of crudes extracts from colored corn (Zea mays. L.) among particle size with different pulverizing methods (pin mill and ultra fine pulverizer). In cytotoxicity test using extracts from the flours grounded by pin mill and ultra fine pulverizer respectively, it showed that A-549 was the highest anticancer activity among in vitro using 4 cancer cell line types (Hep-G2, A-549, HCT-116 and MCF-7). Assessing the antioxidant activities of crude extracted from different pulverizing methods was measured by trolox equivalent antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP). Higher scanvening activity against free radical was observed in the crude extracted from small particle size flours of colored corn than in those of the big particle size.

• Resources Recycling
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• v.13 no.6
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• pp.31-36
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• 2004

This experiment was carried out to examine the effects of morphology on properties of La-Co substituted SrM ferrite. The magnetic properties of calcined and sintered materials were varried with the substitutional amount of La and Co elements in Sr-ferrite. In the substituted SrM ferrite, the atomic fraction x of La is directly related to the mole ratio n of iron oxide and the atomic fraction y of Co by equation x=2ny. The Hcj values of the calcined powder were about 270 kA/m and 240 kA/m with x=0.3 and x=0.2, respectively at stoichiometry, n=6.0. Crystallites of the sintered material were grown with a plate shape, and their size decreased with increasing mole ratios. Such a shape was caused by the initial state of crystallite formed after calcination. In case of x=0.3 and n=6.0, Br was 415 mT and Hcj was 355 kA/m, and in x=0.2 and n=6.0, Br was 410 mT and Hcj was 370 kA/m. The squareness in 2nd quarter of BH curve with x=0.2 was smoothly improved to compared with x=0.3.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.2
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• pp.276-285
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• 2012

The objective of this research is to develop the coating technique by a porous self-fluxing alloy for improving the mechanical properties of run-out table roller surface with the hot rolling. To enhance the durability of run-out table roller with the hot rolling, the high hardness of roller surface should be maintained at high temperatures, and the improvement of wear resistance, corrosion resistance, heat resistance, burn resistance and adhesion resistance should be maintained. In order to be able to transport reliably a hot rolled steel sheet, also, the appropriate friction coefficient on the roller surface should be maintained and the slip between roller and steel should not occur. In this study, the wear resistance of roller increases after the self-fluxing alloy is changed to a cermet by adding the tungsten carbide(WC), and the coefficient of friction increases and the ability of grip is improved because the porosities are made by coating with fine iron powder on the roller surface. As a result, it is found that the ability of grip between the steel and the roller coated by a porous self-fluxing alloy contained to 5 ~ 10 wt% of Fe in the coating layer is improved compared to the roller coated by Ni-Cr. This is because the porosities are made after Fe contained in the roller is partially alloyed by heating with a furnace in the fusing process and the rest is eliminated by oxidation and dissolution.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.12
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• pp.1971-1978
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• 2009

This study investigated the adsorption of safflower yellow dye on wool protein fiber and the optimum dyeing conditions to test color reproducibility. In addition, the effects of mordants on dye adsorption, color, fastness, and photofading rate were also studied. The prepared dye in powder form was characterized with UV-vis spectroscopy and FT-IR spectrometric analysis. The color of dyed fabrics was characterized by CIE $L^*a^*b^*$ coordinates, H V/C, and K/S values. The color reproducibility of the dyed wool fabrics was examined. The amount of dye adsorption increased and also, the shade of the dyed wool fabrics became deeper and more saturated with increasing temperature, time, and dye concentration. The maximum color strength was obtained at pH 3.0. The shade of dyed wool fabrics ranged from light yellow to dark mustard yellow as the pH of the dye bath shifted from alkaline to acidic. Color reproducibility was reliable with color differences in the range of 0.53~1.75. Fastness to dry cleaning was relatively good at 4/5 rating irrespective of mordanting. Fe and Cu mordants showed the least color change of the dyed wool fabrics after exposure to light. Mordants did not contribute to improve dye uptake and color fastness, although they made variations in color tone. Safflower yellow dye can be used satisfactorily without mordants and will not cause damage to the environment.

• Korean Journal of Environmental Agriculture
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• v.19 no.5
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• pp.401-418
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• 2000

1. Production of the artificial zeolite from coal ash Coal fly ash is mainly composed of several oxides including $SiO_2$ and $Al_2O_3$ derived from inorganic compounds remained after burning. As minor components, $Fe_2O_3$ and oxides of Mg, Ca, P, Ti (trace) are also contained in the ash. These components are presented as glass form resulting from fusion in the process of the combustion of coal. In other word, coal ash may refer to a kind of aluminosilicate glass that is known to easily change to zeolite-like materials by hydrothermal reaction. Lots of hot seawater is disposing near thermal power plants after cooling turbine generator periodically. Using seawater in the hydrothermal reaction caused to produce low price artificial zeolite by reduction of sodium hydroxide consumption, heating energy and water cost. As coal ash were reacted hydrothermally, peaks of quartz and mullite in the ash were weakened and disappeared, and new Na-Pl peaks were appeared strengthily. Si-O-Si bonding of the bituminous coal ash was changed to Si-O-Al (and $Fe^{3+}$) bonding by the reaction. Therefore the produced Na-Pl type zeolite had high CEC of 276.7 $cmol^+{\cdot}kg^{-1}$ and well developed molecular sieve structure with low concentration of heavy metals. 2. Utilization of the artificial zeolite in agro-environment The artificial zeolite(1g) could remove 123.5 mg of zinc, 164.7 mg copper, 184.4 mg cadmium and 350.6 mg lead in the synthetic wastewater. The removability is higher 2.8 times in zinc, 3.3 times in copper, 4.7 times in cadmium and 4.8 times in lead than natural zeolite and charcoal powder. When the heavy metals were treated at the ratio of 150 $kg{\cdot}ha^{-1}$ to the rice plant, various growth inhibition were observed; brownish discoloration and death of leaf sheath, growth inhibition in culm length, number of panicles and grains, grain ripening and rice yield. But these growth inhibition was greatly alleviated by the application of artificial zeolite, therefore, rice yield increased $1.1{\sim}3.2$ times according to the metal kind. In addition, the concentration of heavy metals in the brown rice also lowered by $27{\sim}75%$. Artificial Granular Zeolites (AGZ) was developed for the purification of wastewater. Canon exchange capacity was 126.8 $cmol^+{\cdot}kg^{-1}$. AGZ had Na-Pl peaks mainly with some minor $C_3S$ peaks in X-ray diffractogram. In addition, AGZs had various pore structure that may be adhere the suspended solid and offer microbiological niche to decompose organic pollutants. AGZ could remove ammonium, orthophosphate and heavy metals simultaneously. Mixing ratio of artificial zeolite in AGZs was related positively with removal efficiency of $NH_4\;^+$ and negatively with that of $PO_4\;^{3-}$. Root growth of rice seedling was inhibited severely in the mine wastewater because of strong acidity and high concentration of heavy metals. As AGZ(1 kg) stayed in the wastewater(100L) for 4days, water quality turned into safely for agricultural usage and rice seedlings grew normally.

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.307-313
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• 2006

In order to improve the efficiency of methane steam reforming process, a part of the system which produces hydrogen from heavy hydrocarbon resources such as coal, we combined metal catalyst with CaO sorbent and fabricated catalyst/sorbent. To increase the porosity and the compressive strength of sorbent, carbon black and ${\alpha}-alumina$ were mixed with CaO powder during preparation. The effects of sorbent composition on the physical properties were investigated by SEM, TGA, BET, XRD, abrasion strength measuring device and adsorption-desorption instrument. Sorbent with 5 wt％ $Al_2O_3$ and 10 wt％ carbon black showed the best physical features with $7.61kg_f$ strength and 47％ $CO_2$ adsorption capability. Various metal catalysts such as Ni, Co and Fe were supported on the sorbent developed and 10 wt％ Ni/sorbent was selected for methane steam reforming process based on the result of reaction experiment. The reaction system using the catalyst/sorbent showed better $H_2$ productivity compared to the detached system with catalyst and sorbent, indicating the effectiveness of the system developed in this study.