• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.513-523
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• 2005

The contamination of soils and groundwaters in the Dalcheon mine area, Ulsan, is investigated, and a natural attenuation capacity on redox and pH is evaluated. Arsenopyrite, the major source of arsenic pollution in the Dalcheon mine area, is contained up to $2\%$ in tailings. Furthermore, As-bearing minerals such as loellingite, nicolite, rammelsbergite, gersdorffite cobaltite and pyrite are also source of arsenic contamination, which show various concentration of arsenic each other. Surface of pyrite and arsenopyrite in tailings partly oxidized into Fe-arsenates and Fe-oxides, which means a progressive weathering process. There is no relationship between pH and arsenic content in groundwaters, otherwise Eh and arsenic concentration in unsaturated and saturated groundwater shows positive relationship. RMB (Red Mud Bauxite) could be useful as a trigger on natural attenuation due to superior ability of removal capacity of arsenic when contaminated soil and groundwater in the Dalcheon mine area are remediated.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.161-167
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• 1997

The effect of Bituminous and Anthracite coal ash(fly ash) on the performance of Chinese cabbage on an acid soil was studied through a pot experiment. The levels of application of the materials tested were five, 10 and 15% of dry soil weight. Regardless of the kind of fly ash, the application of it, tended to increase the yield of Chinese cabbage by 13 to 24% in fresh weight. Difference in application levels did not result in the difference in increasing the yield of Chinese cabbage. The application of fly ash tended to lower the all of the mineral nutrient contents in the Chinese cabbage, excepting boron. Boron content tended to increase along with the application of fly ash. Bituminous ash raised the pH of soil and increased available P, exchangeable Ca and soluble boron in the soil remarkably. Anthracite ash, on the other hand, did not increase the contents of other components in the soil, than soluble born.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.617-622
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• 1997

The purpose of this study was to investigate the effect of the addition of the extract (0, 2, 4, 6, 8%) and crude enzyme (0, 0.05, 0.1, 0.5, 1%) extracted from the fruits of paper mulberry (Broussonetia kazinoki Siebold) on the tenderness and palatability of Jangchorim. Addition of up to 8% of the extract diminished the shear force by 4.8∼27%, while the addition of up to 1% of the crude enzyme begot 7.8∼34.2% decrease. Also, as the addition of the fruits of paper mulberry increased, the cooking loss was somewhat decreased, an the redness of cooked beef surface and free amino acid content in the liquid part of Jangchorim were generally increased. The contents of the mineral were in the order of Na, K, P, Ca, and Mg when crude enzyme was added. In sensory evaluation, the 4% crude extract from the fruit of paper mulberry and 0.1% addition in its crude enzyme showed the most favorable response.

• Journal of Aquaculture
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• v.10 no.3
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• pp.255-260
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• 1997

In order to investigate the effects of phosphorus and iron levels in the diets containing fish meal as only protein source on the growth, feed conversion, body composition and blood characteristics of juvenile Korean rockfish, either graded monobasic potassium phosphate (MPP) of 1% (MPP-1), 2% (MPP-2), 3% (MPP-3) and 4% (MPP-4), or Fe-citrate (FC) of 0.022% (FC-1), 0.044% (FC-2), 0.066% (FC-3) and 0.088% (FC-4) was added to fish meal-based diet (MMP-0 or FC-0), respectively. Duplicate groups of 40 fish weighing 7g were fed the diets for 21 weeks. Weight gain, feed efficiency and nutrient retention of fish fed diets with different MPP levels were not significantly different (P>0.05). Lipid content of whole body decreased with an increase in dietary MMP (P<0.05). No significant differences were found in the Ht, Hb, total protein, or total glucose in serum among diets containing different MMP levels (P>0.05). Weight gain of fish fed the FC-0, FC-1 adn FC-3 diets was significantly higher than that of FC-4 diet (P>0.05), whereas feed efficiency, nutrient retention, hematological values (Ht, Hb, total protein, and total glucose), and whole body composition were not affected by dietary FC levels (P>0.05). The present results revealed that phosphate or iron supplementation to the diet containing 65% fish meal for juvenile Koran rockfish was not necessary.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.923-928
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• 2016

To increase the consumption of head-type kimchi cabbage leaves as fresh food ingredients, the physicochemical composition was investigated depending on leaf parts. Kimchi cabbage leaves were divided into three portions, such as outer (L1), mid (L2), and inner (L3), and their proximate compositions were determined along with dietary fiber, free sugar, organic acid, free amino acid, and mineral contents. Contents of moisture, crude protein, and crude fat were highest in L1, whereas contents of crude ash and carbohydrate were highest in L3 (P<0.05). Calories ranged 24.5~26.5 kcal/100 g with no significant difference among leaf parts, and dietary fiber content of L1 was highest (P<0.05). Fructose, glucose, and sucrose contents were highest in L3 (P<0.05). Citric acid, malic acid, and succinic acid were detected, and contents of citric acid and malic acid were highest in L3, in contrast, succinic acid was highest in L1 (P<0.05). Glutamic acid, constituting over 30% of the total free amino acid contents, was highest in L3, whereas ${\gamma}-aminobutyric$ acid contents were highest in L1 (P<0.05). K, Na, Ca, and Mg were the major minerals in head-type kimchi cabbage, and their contents showed no significant differences (P<0.05). It can be proposed that marketing of head-type kimchi cabbage as a fresh-cut vegetable could be enhanced due to the different quality characteristics of its leaf parts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.880-888
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• 2016

Changes in quality characteristics of gochujang prepared with different ingredients (white rice, barley, sorghum and millet, bamboo salt) and meju starters were studied. The gochujang samples were fermented for 6 weeks at $40^{\circ}C$ and analyzed for changes in their physicochemical properties and sensory characteristics. Eight different gochujang samples were prepared: WR-SS-AB, WR-SS-ABL, WR-BS-AB, WR-BS-ABL, MG-SS-AB, MG-SS-ABL, MG-BS-AB, MG-BS-ABL (WR: white rice, MG: mixed grains, SS: solar salt, BS: bamboo salt, AB: Aspergillus oryzae/Bacillus subtilis starter meju, ABL: Aspergillus oryzae/Bacillus subtilis/Lactobacillus plantarum starter meju). There were significant differences between experimental groups in terms of moisture content, pH, acidity, and color value. All gochujang samples showed increased moisture contents and pH as well as increased acidity and amino-type nitrogen during fermentation. MG-BS-ABL showed the highest contents of amino-type nitrogen and free amino acids after 6 weeks of fermentation compared with other experiment groups. In addition, MG-BS-ABL showed the highest sensory analysis score, including appearance, flavor, taste, and overall acceptability after the fermentation of samples. Based on the results, MG-BS-ABL exhibited similar quality characteristics as general gochujang but showed the highest sensory scores and contents of amino-type nitrogen and free amino acids. These results might be due to the high protein contents of mixed grains and high mineral contents of bamboo salt and fermented products from mixed probiotic starters.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.3
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• pp.66-74
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• 2016

The aim of this research work is to investigate the mix proportion of multi-component cement incorporating ground granulated blast furnace(GGBFS), fly ash(FA) and silica fume(SF) as an addition to cement in ternary and quaternary combinations. The water-binder ratio was 0.45. In this study, 50% and 60% replacement ratios of mineral admixture to OPC was used, while series of combination of 20~40% GGBFS, 5~35% FA and 0~15% SF binder were used for fundamental characteristics tests. This study concern the GGBFS/FA ratio and SF contents of multi-component cement including the compressive strength, water absorptions, ultrasonic pulse velocity(UPV), drying shrinkage and X-ray diffraction(XRD) analysises. The results show that the addition of SF can reduce the water absorption and increase the compressive strength, UPV and drying shrinkage. These developments in the compressive strength, UPV and water absorption can be attributed to the fact that increase in the SF content tends basically to consume the calcium hydroxide crystals released from the hydration process leading to the formation of further CSH(calcium silicate hydrate). The strength, water absorption and UPV increases with an increase in GGBFS/FA ratios for a each SF contents. The relationship between GGBFS/FA ratios and compressive strength, water absorption, UPV is close to linear. It was found that the GGBFS/FA ratio and SF contents is the key factor governing the fundamental properties of multi-component cement.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.2
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• pp.70-77
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• 2012

The Ladle Furnace Slag, about 20% of the electric arc furnace slag, has high content of free CaO and free MgO, which generates the expansion collapse by hydration reaction. Although many researchers have been endeavoring to recycle the EAF reducing slag in construction fields, there is not found the effective recycling method up to now. However, the LFS(Ladle Furnace Slag) contains mineral composition of the system of calcium aluminate with high-reactivity. Therefore, it is possible to developed the quick setting property and the high strength at the early age by the rapid cooling. This study aimed to check the reactive minerals and predict the reactivity with water on the LFS discharged from different steel product plants. The test results show that many types of LFS has hydration reactivity and can use in construction field as a inorganic binder with the rapid setting property.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.1
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• pp.1-9
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• 2014

In this paper, $CO_2$ amount is evaluated considering repairing timing and unit $CO_2$ amount per repair method including various stage of material manufacturing, moving, and construction. Four mix proportions with mineral admixture are considered and repairing timing/numbers are simulated based on the results from Life 365 which can handle chloride penetration. Furthermore two repair methods (simple cover concrete replacement and replacement with electro-chemical method for removing chloride content) are considered and the related $CO_2$ emissions are evaluated. From the study, the case with high W/B (water to binder ratio) ratio shows smaller $CO_2$ emission in construction stage but it increases more rapidly with increasing number of repair. $CO_2$ emission considering electro-chemical method greatly increases with the increasing unit $CO_2$ for the repairing method. The numbers of jumping step (repairing number) are evaluated to be 9 for WB37-OPC, 18 for WB50-OPC, 4 for WB40-SG, and 7 for WB47-SG respectively. RC structures with the longer maintenance free period are evaluated to be advantageous for saving $CO_2$ emission.

• The Korean Journal of Quaternary Research
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• v.7 no.1
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• pp.69-91
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• 1993

A total of 76 surface sediment samples, collected from the Korean west coast and the eastern Yellow Sea areas, were analyzed for their elemental composition in order to understand the geochemical characteristics of these deposits. The analyzed elements included 9 major elements (Al, Fe, Na, K, Mg, Ca, Ti, P, Mn), 8 minor elements (Sr, Ba, V, Cr, Co, Ni, Cu, Zn), organic carbon and calcium carbonate. Contents of most analyzed elements, excluding K and Ba, were generally low compared to those of average crust. Contents of most elements, except K and Ca, also correlated with sediment grain size, though the degree of relationship varied widely from one element to another. For fine-grained sediments, a distinction could be made between those in the central Yellow Sea and those in the Keum Estuary based on their characteristic elemental composition: the former were rich in Fe, Na, K, Mg, Ca and V, and the latter in Mn, Co and Ni. The element/aluminium ratios, on the other hand, showed that the central Yellow Sea muds were enriched in Fe, Mg, V, Ni, Cu and Zn and depleted in K, Mn, Ba and Sr relative to the mud located near the Korean Peninsula. Based on the analysis of these results, as well as of the influences of particular mineral phases or pollution effects, we could suggest geochemical criteria which can be used in distinguishing muds from the two different sources, the Keum River and the Yellow River: the former by the higher Mn content and the latter by the higher Mg and V contents, relative to each other.