• 한국주조공학회지
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• 제1권2호
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• pp.2-9
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• 1981

Graphite spheroidization and scaling resistance of cast iron containing 5-10% Al were investigated. It is impossible to obtain spheroidal graphite in cast iron containing Al with 8 % and over, but possible to obtain spheroidal graphite even in cast iron with an Al content of about 10 % by increasing Si content. In the scaling test carried out under the heating condition of $950^{\circ}C$ in air for total of 50 hours, the scaling resistance of cast iron containing Al with 8 % and over was remarkably superior, and also spheroidal graphite cast iron was superior to flake graphite cast iron. The scale became thinner more compacts and more protective with increasing Al content.

• 한국미생물·생명공학회지
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• 제31권4호
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• pp.435-438
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• 2003

Iron required by all organisms is related with diverse biological processes. Most eukaryotes need extra iron to maintain their nutrition balance. However, extra iron supplement gives many problem to solubility in the cells. To increase the bio-availability of iron in cells, yeast was applied to carry the iron with solubility. Selection of yeast mutants with enhanced iron uptake were performed by mutagenesis using the alkylation agent EMS. Eleven mutant strains with enhanced iron uptake were selected by the measurement of iron content with atomic absorption spectrometer. The iron content in mutants was 1.5- to 2.5-fold more than that in wild-type. These mutants could be served as iron-fortified nutrients for food and feed.

• 한국식품조리과학회지
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• 제33권1호
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• pp.113-120
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• 2017

Purpose: Lipid autoxidation of a soybean oil-in-water emulsion with high oil content was studied under after basil extract and/or iron addition. Methods: The emulsion consisted of tocopherol-stripped soybean oil (40 g), citrate buffer (60 g, pH 4.0), and/or $FeSO_4$ (0.5 mg) with 75% ethanol extract (200 mg/kg) of basil (Ocimum basilicum). Lipid oxidation was evaluated using headspace oxygen content, hydroperoxide contents, and p-anisidne values of the emulsion. Polyphenol compound retention in the emulsion during oxidation was determined spectrophotometrically. Results: Addition of basil extract significantly (p<0.05) decreased reduced hydroperoxide contents of the emulsion, and iron significantly (p<0.05) increased anisidine values and decreased oxygen contents. Co-addition of basil extract and iron showed significantly (p<0.05) lower reduced hydroperoxide contents in the emulsion than compared to those of the emulsion with added iron and the control emulsion without basil extract nor or iron. During the emulsion oxidation, polyphenol compounds in the emulsion with added basil extract were degraded, but more slowlywhich was slowed degraded in the presence of iron. Conclusion: The iIron increased the lipid oxidation through hydroperoxide decomposition, and basil extract showed antioxidant activity through radical-scavenging and iron-chelation. Polyphenol degradation was decelerated by iron addition, which suggested suggests iron chelation may be more preferred topreferentially activated over radical scavenging in the antioxidant action by of basil extract in the oil-in-water emulsion with high oil content.

• 한국주조공학회지
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• 제24권4호
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• pp.217-224
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• 2004

The effect of casting variable on the fluidity of high silicon, especially hypereutectic, heat-resistant ductile cast iron melt was investigated. When pouring temperature and silicon content were constant, that was increased with carbon content. When the pouring temperature and carbon content were constant, that also increased with the silicon content. Even though these results were thought to be caused by the high heat of fusion evolved during the crystallization of proeutectic graphite nodules, further research seemed to be needed. The fluidity for taller sprue was higher than that for smaller one.

• 동아시아식생활학회지
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• 제14권1호
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• pp.27-33
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• 2004

The objectives of the present study were to measure the content of iron, copper and zinc in human milk and to estimate the intake of iron, copper and zinc of breast-fed infants during the early period of lactation. Twenty-five lactating women who delivered in a hospital in Seoul volunteered for the study. Milk samples were collected at day 2, 3, 4, 5, 6, 7, 15 and 30 postpartum. The contents of iron, copper and zinc were determined using the atomic absorption spectrophotometer after wet digestion. The intakes of iron, copper and zinc of infants were estimated by multiplization with the infant milk intake reported in our laboratory. The content of iron was 0.58 $\mu\textrm{g}$/g in colostrum, 0.48 $\mu\textrm{g}$/g in transitional milk and 0.39 $\mu\textrm{g}$/g in mature milk while the estimated iron intake of infants was 271, 255 and 259 $\mu\textrm{g}$/day, respectively. The content of copper in the milk was 0.45 $\mu\textrm{g}$/g in colostrum, 0.43 $\mu\textrm{g}$/g in transitional milk and 0.33 $\mu\textrm{g}$/g in mature milk while the estimated copper intake of infants was 210, 229 and 220 $\mu\textrm{g}$/day, respectively. The content of zinc in the milk was 5.24 $\mu\textrm{g}$/g in colostrum, 3.70 $\mu\textrm{g}$/g in transitional milk, 2.93 $\mu\textrm{g}$/g in mature milk while the estimated zinc intake of infants was 2452, 1968, and 1949 $\mu\textrm{g}$/day, respectively. These results suggest that copper and zinc intake of infants are met to RDA but iron is not.

• Journal of Nutrition and Health
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• 제26권6호
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• pp.703-714
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• 1993

The iron content of 178 food items were analyzed by ICP to provide database to calculate dietary intake of iron in Korea. The analysis data showed significant deviations of iron contents in some food items compared with Food Composition Table of KRNI which is most widely used at present. Three day dietary intake records were collected from 96 female college students to estimate mean daily iron intake and bioavailability of dietary iron. Mean daily intake of total iron in the study subjects was 13.2mg and heme iron intake was 0.94mg, 6.7% of total iron intake. BGioavailability of dietary iron was calculated by two methods. Total absorbable iron was calculated by the method of Monsen, body iron storage of the subjects being estimated with serum ferritin concentrations, was 1.21mg and bioavailability of dietary iron was thus 9.3%. Bioavailability calculated with the method by Hallberg was 11.22%. Two values of dietary iron bioavailability of the present study are lower than the reported values in adult women consuming typical western diets but within the range estimated for vegetarians. Considering high prevalence of iron deficiency based on serum ferritin concentrations and low bioavailability of diet in young adult Korean women, more efforts should be made to increase the content and bioavailability of iron in diet of Korea adult women.

• 한국표면공학회지
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• 제38권4호
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• pp.156-162
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• 2005

Nickel-iron nanocrystalline alloys with different compositions and grain sizes were fabricated by electro-plating for MEMS devices. The iron content of the deposits was changed by varying the nickel/iron ion ratio in the electrolyte. X-ray diffraction (XRD) analysis was applied for measuring the strength of the texture and grain size of the deposits. The nickel/iron atom ratio of the deposits was analyzed by EDS. The hardness of the alloys was evaluated by Vickers hardness indenter. The internal stress of the deposits was measured by Thin Film Stress Measurement using Stoney's formula. Surface morphology and roughness were investigated by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The results of this study revealed that at a grain size of approximately $17\~24$nm the hardness, internal stress and roughness depend strongly on the iron content. With increasing the iron content, the hardness and internal stress of the deposits increased. An excellent correlation between the increase in the internal stress and the loss of (200) texture was found.

• 자원환경지질
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• 제8권3호
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• pp.165-168
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• 1975

The grade and recovery rate and its sulphur content of iron concentrate compared respectively as varied with redcued size using the Crocket Magnetic Separator and the Wet-Drum-Magnetic Separator in the magnetic separation test of iron ore from Yangyang mine. The content of sulphur was decreased distinctly as the size was finer. In case of the sample of -100 mesh, using the Crocket Magnetic Separator, the sulphur content of iron ore was decreased to 0.10% and its grade increased to 67.0%, but the recovery rate was no more than 85.1%. In the Wet-Drum type, the grade and the recovery rate of concentrate was better than those in the Crocket Magnetic Separation, but the content of sulphur was more than that in the Crocket Magnetic Separation. The Crocket type is suitable for less sulphur content while the Wet-Drum Magnetic Separator is suitable for better the grade recovery rate of the magnetic concentrate.

• 한국주조공학회지
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• 제9권1호
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• pp.80-88
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• 1989

SGCI(Spheroidal Graphite Cast Iron), CVGCI(CV Graphite Cast Iron) and FGCI(Flake Graphite Cast Iron) having different contents of Mn($0.25%{\sim}0.85%$) and Ni($0.3%{\sim}1.2%$) were produced, respectively. The thermal expansion and thermal conductivity of the cast iron were investigated in the temperature range of $50^{\circ}C{\sim}300^{\circ}C$. As the graphite nodularity of the cast iron increases, thermal expansion coefficient increases, thermal conductivity and electrical conductivity to thermal conductivity ratio decrease. The thermal expansion coefficient of the cast iron increases with increasing Mn content and decreases with increasing Ni content. The thermal conductivity of the cast iron decreases with increasing Mn and Ni contents.

• 대한금속재료학회지
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• 제50권6호
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• pp.419-425
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• 2012

The purpose of this research was to develop a low Ni austenitic cast iron through replacing Ni by Cu and Mn because they are cheaper than Ni. The effect of the Cu content (6-12 wt%) on the microstructure characteristics was investigated in Fe-3%C-16%(Ni+Cu+Mn) cast iron. Contrary to general effect of the Cu on cast iron, the result of the microstructure analysis indicated that bainite and cementite were formed in high Cu content (>8 wt%Cu). A crystallized Cu-solution (Cu-Mn) phase and MnS in the Cu-solution were formed. The quantity of those phases increased as the Cu content increased. Consequently, the high Cu content in the composition ratio (Ni+Cu+Mn=16%) caused the formation of Cu-Mn/MnS and those phases decreased the effect of Cu and Mn on austenite formation. For this reason, bainite and cementite were formed in high Cu content.