• Journal of Korea Foundry Society
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• v.16 no.2
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• pp.141-148
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• 1996

In high chromium cast iron, the control of matrix microstructure as well as carbide structure is important to the performance as a wear resistant material. In this study, 3.0% C-24.0% Cr white cast irons with various molybdenum contents(residual, 1.0%, 3.0% and 5.0%) were solidified conventionally and unidirectionally for studying their effects on the microstructure and hardness. In the conventional casting, two sets of castings were poured from each melt. One set of the castings consisted of cylindrical bars of 10 and 20mm by 155mm long. The second set of the castings was a cylindrical bar of 30mm by 200mm long. On the other hand, a pep-set mold set on the Cu plate was employed to make the solidification unidirectionally. X-ray diffraction method was used to observe retained austenite and carbides in the high chromium cast iron. The morphology of eutectic $M_7C_3$ carbides changed from needle-like type to nodular type with the increase of Mo content. And, the presence of $M_2C$ carbides was identified in the sample where Mo was added over 3.0 %. Primary and eutectic carbides appeared as rod type and corngrain type, respectively in the unidirectionally solidified samples which were cut to parallel to the solidification direction. In the EDX analysis, Cr concentration was higher in the primary and eutectic $M_7C_3$ carbides, Mo in the $M_2C$ carbides, and Fe in the matrix.

• Journal of the Korean Ceramic Society
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• v.43 no.10 s.293
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• pp.601-606
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• 2006

For the purpose of development of red color stain body, bone body which can be fired at 1180$^{\circ}C$ and has a higher degree of whiteness and transmission was developed and a property experiment depending on the content of $Fe_2O_3$ was performed. For manufacturing this body, 9% addition of bone ash to commercialized white body resulted in the best whiteness and proper physical characteristics. In an experiment of oxidized iron addition using this body as a basis, red color stain body fired up to 1150$^{\circ}C$ following the addition of 6% oxidized iron showed physical characteristics such as 5.4R color closer to theory color, 0.08% water absorption rate, 9.1% shrinkage, and 1861 kgf/$cm^2$ bending strength, which implies that this body is suitable for red color stain body.

• Journal of The Korean Astronomical Society
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• v.47 no.4
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• pp.147-152
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• 2014

We present measurements of the Fe $K{\alpha}$ emission line of the intermediate polar V1223 Sagittarii observed with the Suzaku satellite. The spectrum is modeled with an absorbed thermal bremsstrahlung spectrum and three Gaussians for the three components of the Fe $K{\alpha}$ lines. We resolve the neutral or low-ionized (6.41keV), He-like (6.70keV), and H-like (7.00keV) iron lines. We also obtain a thermal continuum temperature of 25 keV, which supports a thermal origin of the hard X-rays observed from the shock heated layers of gas between the white dwarf and the shock front. Hence, we believe that the He-like and H-like lines are from the collisional plasma. On the origin of the Fe $K{\alpha}$ fluorescence line, we find that it could be partly from reflections of hard X-rays from the white dwarf surface and the $N_H$ absorption columns. We also discuss the Fe $K{\alpha}$ emission line as veritable tool for the probe of some astrophysical sites.

• Journal of Conservation Science
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• v.33 no.6
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• pp.507-518
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• 2017

Through a combination of scientific analytical methods, the coloring materials used in $20^{th}$ century paintings in historical churches of Baclayon, Dauis and Loay, which are municipalities in Bohol, Philippines, were studied. Inorganic pigments were identified using SEM-EDS and XRD. Iron-based pigments were commonly found in the paintings, yielding dark yellow and brown colors. Zinc oxide was identified as the white pigment in the ceiling paintings of Dauis Church and Loay Church, while titanium dioxide was detected in the column painting in Baclayon Church. Organic analysis showed the presence of Pigment Yellow 3, a synthetic organic pigment. Paint layers, as well as other components of the samples such as grounds and metal leaves, were examined microscopically. It was observed that different types of grounds were applied on different types of surfaces. Moreover, organic pigments were found in combination with white extender materials. Microscopic examination also revealed alterations in the artworks, such as the overpaint layer found in the samples from Baclayon Church cornice and the imitation metal leaf layers applied over the original gilt surface in the Loay Church retablo.

• International Journal of Advanced Culture Technology
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• v.12 no.3
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• pp.52-56
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• 2024

The ancient ancestors of Korea believed that the five directions of east, west, south, and north were important, and that there was a god in charge of each of the five directions, and that he was in charge of the universe, nature, and life. In Korea, the traditional colors follow the Yin and Yang Five Ceremony. The five elements were placed in the bearings symbolized by wood, fire, earth, iron, and water, namely east, south, center, west, and north, and the symbolic colors were called blue, red, yellow, white, and black according to their connotations. These colors should be the five element colors. In studying the colors of the five elements, this researcher found that the five element colors were inconsistent in each of the existing studies. Therefore, the characteristics of the Yin and Yang Five Elements were carefully examined, and the Five Element Colors pursued by the ancestors were identified, and the Five Element Colors were defined to fit the present era. According to modern color standards, the three primary colors of color, cyan, magenta yellow, and the five colors of pure black and pure white, can be said to be the colors that most correspond to the Yin and Yang Five Symbols.

• Korean Journal of Materials Research
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• v.10 no.7
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• pp.489-492
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• 2000

Three different white cast irons alloyed with Cr and Si were prepared in order to study their distribution be-havior in matrices and carbides. The specimens were produced using a 15kg-capacity high frequency induction fur-nace. Melts were super-heated to $1600^{\circ}C$, and poured at $1550^{\circ}C$ into a pepset mold. Three combinations of the alloys were selected so as to observe the distribution behavior of Cr and Si : 0.5%C-25.0%Cr-1.0%Si(alloy No. 1), 0.5%C-5.0%Cr-1.0%Si(alloy No. 2) and 2.0%C-5.0%Cr-1.0%Si(alloy No. 3). Cellular $M_7C_3$ carbides-$\delta$ferrite eutectic were developed at $\delta$ferrite liquid interfaces in the alloy No. 1 while only traces of $M_7C_3$ carbides-$\delta$ferrite eutectic were precipitated in the alloy No. 2. With the addition of 2.0% C and 5.0% Cr, ledeburitic $M_3C$ carbides instead of cellular $M_7C_3$ carbides were precipitated in the alloy No. 3. Cr was distributed preferentially to the $M_7C_3$ carbides rather than to the matrix structure while more Si was partitioned in the matrix structure rather than the $M_7C_3$ carbides. $K^m$ for Cr was ranged from 0.56 to 0.68 while that for Si was from 1.12 to 1.28. $K^m$ for Cr had a lower value with increased carbon contents. The mass percent of Cr was higher in the $M_7C_3$ carbides with increased Cr contents.

• Korean Journal of Materials Research
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• v.10 no.6
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• pp.409-414
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• 2000

Three different white cast irons alloyed with Cr, V, Mo and W were prepared in order to study their transformation behavior of matrix structures in heat-treated conditions. The specimens were produced using a 15kg-capacity high frequency induction furnace. Melts were super-heated to $1600^{\circ}C$, and poured at $1550^{\circ}C$ into Y-block pepset molds. Three combinations of the alloying elements were selected so as to obtain the different types of carbides and matrix structures : 3%C-10%Cr-5%Mo-5%W(alloy No. 1), 3%C-10%V-5%Mo-5%W(alloy No. 2) and 3%C-17%Cr-3%V(alloy No. 3). The heat-treatments were conducted as follows: frist of all, as-cast specimens were homogenized at $950^{\circ}C$ for 5h under the vacuum atmosphere. Then, they were austenitized at $1050^{\circ}C$ for 2h and followed by air-hardening in air. The air-hardened specimens were tempered at $300^{\circ}C$ for 3h. The observation of morphology of the matrix structures was carried out in the states of as-cast(AS), air-hardened(AHF) and tempered(AHFT). The matrix structures of each alloy were almost fully pearlitic in the as-cast state but it was transformed to martensite, tempered martensite and retained austenite by the heat-treatments such as air-hardening and tempering.

• Journal of Nutrition and Health
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• v.44 no.3
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• pp.203-211
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• 2011

Previous studies have shown that plant-based vegetarian diets, which typically contain a variety of antioxidants and dietary fiber, help reduce the risk of heart disease, diabetes, obesity, and cancer. However, some studies have reported that vegetarian diets can lead to deficiencies in protein and trace minerals compared to non-vegetarian diets. This study was conducted to compare anthropometric measurements, blood parameters, dietary intake, and hair mineral status in long-term vegetarians (MV; moderate vegan, LV; lacto-ovo vegetarian) and non-vegetarians (NV). Thirty MV (12 males, 18 females; mean age, $50.58{\pm}5.05$ years), 15 LV (11 males, four females; mean age, $49.45{\pm}4.97$ years), and 30 NV (15 males, 15 females; mean age, $48.90{\pm}3.62$ years) participated. No significant differences were observed for age, height, weight, or body mass index, but body fat was significant lower in MV and LV males than that in NV males. White blood cell counts of MV, LV, and NV male subjects were significantly different. Dietary intake data showed that plant protein and plant iron intake were significantly higher in MV and LV than those in NV. Animal protein, animal fat, and animal iron intake were significantly higher in NV than those in MV and LV. A hair mineral analysis showed that calcium and iron were higher in the hair of MV and LV than those in NV. Zinc concentration in hair was not significantly different among the groups. The results suggest that vegetarian diets are adequate to sustain mineral status to at least the same degree as that of non-vegetarian diets.

• Korean Journal of Community Nutrition
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• v.8 no.6
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• pp.977-985
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• 2003

This study was done to evaluate the health and nutritional status of female college students in Seoul. The subjects were 63 healthy college students aged 20 to 29 years. Their body composition, dietary intakes, clinical blood indices were investigated. Their body composition was determined by means of a multifreqency bioelectrical impedance analysis. Their dietary intake was determined using 3-day record method and their nutrient intake was analyzed by Computer Aided Nutritional analysis program for professional (CAN-pro). Their hemoglobin, hematocrit, red blood cell (RBC), white blood cell (WBC) and mean corpuscular volume (MCV) were determined by semi-automated microcell counter (F-520). Their plasma total cholesterol, TG, and HDL-cholesterol levels were measured using test kits. All data were statistically analyzed by SAS PC package program. Their average consumption of calcium, iron vitamin A, vitamin B2 and niacin were 63.3%, 65.0%, 85.2%, 89.2% and 95.2% of RDA, respectively. The overall mean values of the hematological indices in the female college students were within the normal range. However anemic subjects with hemoglobin (< 12 g/dl) and hematocrit (<36%) accounted for about 20% of the subjects. The mean levels of total cholesterol, HDL-cholesterol and TG were 188.4mg/dl, 69.9mg/dl and 67.4mg/dl, respectively. The percentages of the subjects with plasma total cholesterol level (> 200mg/dl) and LDL-cholesterol (＞130mg/dl) were about 41% and 30.4%, respectively. The data showed a significantly positive correlation between either body fat (%) or BMI and TG. However. there was a significantly negative correlation between either body fat (%) or BMI and HDL-cholesterol. These overall results suggest that it is necessary for college women to be educated regarding consuming more iron and vitamin C and less fat, in order to prevent iron deficiency anemia and/or cardiovascular diseases in later life.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1114-1121
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• 2016

This study investigated the food components and antioxidant activities of dried Jerusalem artichoke (Helianthus tuberosus L.) with white and purple colors. For the proximate composition of dried Jerusalem artichoke, regardless of color, carbohydrate content was highest, followed by crude protein, ash, and moisture contents, and breed-specific differences were not detected. The highest mineral content of dried Jerusalem artichoke was potassium, followed by calcium, magnesium, sodium, and iron. The major minerals of white color sample were calcium, magnesium, and zinc, whereas those of the purple color sample were potassium, sodium, copper, and manganese, and no significant differences between the samples were detected. The main amino acid of dried Jerusalem artichoke was arginine, regardless of color, followed by asparagine, aspartic acid, and ${\gamma}-amino-n-butyric$ acid in order. Cysteine, leucine, and tyrosine were significantly (P<0.05) more abundant in the purple color sample than in the white color sample. In contrast, phosphoethanolamine was significantly (P<0.05) higher in the white color sample than in the purple color sample. Antioxidant activity was higher in the purple color sample than in the white color sample for all activities except the 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay methodology. Ferric-reducing antioxidant power and oxygen radical absorbance capacity assays at low concentrations of extracts found no differences between the two samples, although the purple sample at high concentration showed relatively high antioxidant activities.