• Title/Summary/Keyword: Compositions

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Dielectric Properties and Microstructure of Modified $CaZrO_3$ for Application of Ni-MLCC with NPO Temperature Characteristics (NPO 온도특성의 Ni-MLCC 응용을 위한 CaZrO3의 유전특성 및 미세구조)

  • Chun, Myoung-Pyo;Myoung, Seong-Jae;Han, Ik-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.30-32
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    • 2005
  • The effects of mole ratio and Ti-ion on the dielectric properties and microstructure of modified $CaZrO_3$ composition such as $(Ca_{0.7}Sr_{0.3})_m(Ti_yZr_{1-y})O_3$ were investigated. Ti ions substituted on Zr-sites in these modified $CaZrO_3$ composition strongly affect the sintering density and microstructure of the fired ceramic body. With increasing the amount of Ti substituted on Zr-sites, the sintered density rapidly increased and the dense microstructures were obtained for the compositions having mole ratio of 1.01, whereas the sintered density and microstructures are nearly constant with the content of Ti-ion for the compositions having mole ratio of 0.99. With increasing the content of Ti ion, the curve of TCC (temperature coefficient of capacitance) as a function of temperature rotated clockwise and satisfied the COG characteristics for both of compositions with mole ratio of 0.99 and 1.01. The content of Ti ion seems to be more effective than mole with respect to the controlling of firing and TCC.

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Functional Ingredient Compositions of Soybean Curds(Tofu) Made with Black Soybeans(Huktae) and White Soybeans(Baktae) (백태와 흑태를 원료로 하여 제조된 두부의 기능성 성분 분석)

  • Kim, Kang-Sung
    • The Korean Journal of Food And Nutrition
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    • v.20 no.2
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    • pp.158-163
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    • 2007
  • The compositions of tofus made with Baktae and Huktae were compared to those made with other respective types of soybeans. The lipid and protein contents of Baktae were 20.8% and 39.7%, while those of Huktae were 15.8% and 41.1%, respectively. In both soybean types, linoleic acid(18:2), oleic acid(18:1), and palmitic acid(16:0) accounted for more than 80% of the total fatty acids. The tofu made from Baktae was whiter than the tofu made from Huktae, as exhibited by a higher Hunter's L-value. The lipid content of the Baktae tofu(4.41%) was higher than that of the Huktae tofu(3.26%). The amino acid compositions of the Huktae and Baktae tofus were similar, with glutamic acid and aspartic acid being the most abundant amino acids in both tofus. However, the content of the limiting amino acid, methionine, increased 2.5-fold in the tofus as compared to the soybeans, on a per gram protein basis. Isoflavones were lost during tofu making as contents for the tofu were 20${\sim}$25% of those for the soybeans.

Quantification of $Cu(In_xGa_{1-x})Se_2$ Solar Cell by SIMS

  • Jang, Jong-Shik;Hwang, Hye-Hyen;Kang, Hee-Jae;Min, Hyung-Sik;Han, Myung-Sub;Suh, Jung-Ki;Cho, Kyung-Haeng;Chung, Yong-Duck;Kim, Je-Ha;Kim, Kyung-Joong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.275-275
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    • 2012
  • The relative composition of $Cu(InGa)Se_2$ solar cells is one of the most important measurement issues. However, quantitative analysis of multi-component alloy films is difficult by surface analysis methods due to severe matrix effect. In this study, quantitative depth profiling analysis of CIGS films was investigated by secondary ion mass spectrometry (SIMS). The compositions were measured by SIMS using the alloy reference relative sensitivity factors derived from the certified compositions and the total counting numbers of each element. The compositions measured by SIMS were linearly proportional to those by inductively coupled plasma-mass spectrometry (ICP-MS) using isotope dilution method. In this study, the quantification measured by ICP-MS method is compared with the composition calculated by SIMS depth profiles with AR-RSFs obtained from the reference. The SIMS depth profile of CIGS thin films according to the manufacturing condition was converted into compositional depth profile.

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Chemical Compositions and Pyrolysis Characteristics of Oil Shales Distributed in Korea

  • Yang, Moon Yul;Yang, Myoung Kee;Lee, Sang Hak;Wakita, Hisanobu
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.487-492
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    • 1995
  • The chemical compositions and pyrolysis characteristics of oil shales and source rocks distributed in the southwestern and southeastern parts of the Korean peninsular have been investigated. In order to compare the results of Korean samples with those of shales giving high oil yields, two Colorado oil shale samples and one Paris source rock samples were also investigated. Chemical compositions of the samples were analysed by means of gravimetry, CHN analysis, X-ray diffraction method, inductively coupled plasma atomic emission spectrometry and atomic absorption spectrometry. A custom made pyrolyser and a Rock-Eval system were used for the pyrolysis studies. Pyrolyses of the samples were carried out by means of a temperature controlling device to $600^{\circ}C$ at a heating rate of $5^{\circ}C/min$ with a helium flow rate of $1200m{\ell}/min$. The results of pyrolysis study indicated that Colorado shale samples belong to type I and all the other samples belong to type II.

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Chemical Composition of Green Teas According to Processing Methods and Extraction Conditions

  • Kim, Young-Kyung;Oh, Yoo-Jin;Chung, Jin-Oh;Lee, Sang-Jun;Kim, Kwang-Ok
    • Food Science and Biotechnology
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    • v.18 no.5
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    • pp.1212-1217
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    • 2009
  • This study examined the influence of manufacturing processes and extraction conditions on the chemical compositions of green tea. Green tea samples grown in various areas (Korea, China, and Japan) and processed by 4 different methods (steaming, pan-firing, steaming and pan-firing, and heavy roasting after steaming and pan-firing) were collected for study. The chemical compositions of the green tea extracts and infusions were different according to their processing methods and extraction conditions, including catechins, caffeine, and free amino acids contents. In all samples analyzed, (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC), and theanine were determined as the major catechins and free amino acid, respectively. Studies of samples grown in the same area (Jeju; Korea) showed that there were significant differences in the concentrations of catechins and caffeine in extract and infusion according to the processing methods. These results indicate that processing methods influenced the chemical compositions of the green tea extracts and infusions.

High Electrochemical Activity of Bi2O3-based Composite SOFC Cathodes

  • Jung, Woo Chul;Chang, Yun-Jie;Fung, Kuan-Zong;Haile, Sossina
    • Journal of the Korean Ceramic Society
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    • v.51 no.4
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    • pp.278-282
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    • 2014
  • Due to high ionic conductivity and favorable oxygen electrocatalysis, doped $Bi_2O_3$ systems are promising candidates as solid oxide fuel cell cathode materials. Recently, several researchers reported reasonably low cathode polarization resistance by adding electronically conducting materials such as (La,Sr)$MnO_3$ (LSM) or Ag to doped $Bi_2O_3$ compositions. Despite extensive research efforts toward maximizing cathode performance, however, the inherent catalytic activity and electrochemical reaction pathways of these promising materials remain largely unknown. Here, we prepare a symmetrical structure with identically sized $Y_{0.5}Bi_{1.5}O_3$/LSM composite electrodes on both sides of a YSZ electrolyte substrate. AC impedance spectroscopy (ACIS) measurements of electrochemical cells with varied cathode compositions reveal the important role of bismuth oxide phase for oxygen electrocatalysis. These observations aid in directing future research into the reaction pathways and the site-specific electrocatalytic activity as well as giving improved guidance for optimizing SOFC cathode structures with doped $Bi_2O_3$ compositions.

The Effect of Processing Parameters on HTS Tube Characteristics

  • Jung, Sengho;Jang, Guneik;Ha, Dongwoo;Sung, Taehyun
    • Transactions on Electrical and Electronic Materials
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    • v.5 no.2
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    • pp.55-60
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    • 2004
  • High-temperature Superconductor(HTS) tubes were fabricated in terms of different chemical compositions and various SrSO$_4$additions by centrifugal forming method. For powder melting by induction the optimum range of melting temperatures and preheating temperature were 1050$^{\circ}C$, 1100$^{\circ}C$ and 550$^{\circ}C$ for 30 min, respectively. The mould rotating speed was 1000 rpm. A tube was annealed at 840$^{\circ}C$ for 72 hours in oxygen atmosphere. The plates like grains more than 20 $\mu\textrm{m}$ were well developed along the rotating direction of mould regardless of initial chemical compositions and the amounts of SrSO$_4$in Bi2212. The specimen with Bi2212 composition exhibited T$\_$c/ of 83 K, while the specimens fabricated with other compositions are lower than 60 K. The measured I$\_$c/ and J$\_$c/ at 77 K(B = 0 T) in Bi2212 with 7 % SrSO$_4$ composition were about 680 A and 380 A/$\textrm{cm}^2$.

Studies on the Lipid Components of Various Ginsengs ll. Lipid and Fatty Acid Compositions of the Bound Lipids (각국 인삼의 지방질성분에 관한 연구 제2보, 결합 지방질중의 지방질 및 지방산 조성)

  • Choe, Gang-Ju;Kim, Man-Uk;Kim, Dong-Hun
    • Journal of Ginseng Research
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    • v.9 no.2
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    • pp.204-212
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    • 1985
  • Lipid and fatty acid compositions of the bound lipids in Panax quinquefolium (Korea, Japan and China), Panax quinquefolium (America, Canada) and Panax notoginseng (China) were studied by means of silicic acid column chromatography, thin-layer chromatography and gas-liquid chromatography. The could lipid contents in various ginsengs were 0.29 to 0.48%, in which neutral lipid fractions were 63.6 to 67.3%, glycolipid fractions 21.9 to 25.7% and phospholipid fractions 7.7 to 12.4%. The content compositions of neutral lipid fractions were lower and those of glycolipid and phospholipid fractions were higher in the bound lipids than in the free lipids from the various ginseng. The major components were fatty acids, diglycerides and free sterols in neutral lipid fractions, monogalactosyl diglyceride, sterol glucoside and esterified steryl g1ycoside in glycolipid fractions and phosphatidyl glycerol, phosphatidyl ethanolamine and phosphatidic acid in phosphoipid fractions. Seventeen fatty acids were analyzed in the four bound lipid fractions from the various ginsengs and main fatty acids were linoleic acid, palmitic acid and oleic acid. Total saturated fatty acid and palmitic acid contents were higher and total unsaturated fatty acid and linoleic acid contents lower in the total bound lipids than in the total free lipids from the various ginsengs.

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The Relationship between Chemical Compositions, Meat Quality, and Palatability of the 10 Primal Cuts from Hanwoo Steer

  • Jung, Eun-Young;Hwang, Young-Hwa;Joo, Seon-Tea
    • Food Science of Animal Resources
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    • v.36 no.2
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    • pp.145-151
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    • 2016
  • The relationship between chemical compositions, meat quality traits, and palatability attributes in 10 primal cuts from Hanwoo steer carcasses were assessed. Sensory palatability attributes of Hanwoo beef were more closely related with fat content than to moisture or protein content. Among the chemical compositions, only fat had a significant correlation with juiciness (0.67, p<0.001), tenderness (0.32, p<0.05), and overall palatability (0.56, p<0.001). Oleic acid (%) was not significantly related with overall palatability (p>0.05). Overall palatability was negatively correlated with drip loss (−0.32, p<0.05), cooking loss (−0.36, p<0.05), and shear force (−0.54, p<0.01). The correlation between fat content and overall palatability was increased when higher fat cuts (Ansim, Dungsim, Chaekeut, Yangjee, and Kalbi) were analyzed, compared to lower fat cuts (Moksim, Abdari, Udun, Suldo, and Satae). Also, the correlation between shear force and overall palatability was decreased in lower fat cuts compared to higher fat cuts. Our results suggest that the palatability of Hanwoo beef can be improved by increasing fat content in muscles, as increased fat content leads to an increase in sensory tenderness, flavor, and juiciness.

Effects of Regularly Performed Walking on the Bilateral Limb Compositions of Post-Stroke Korean Men

  • Jee, Hae Mi
    • Journal of International Academy of Physical Therapy Research
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    • v.9 no.1
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    • pp.1413-1419
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    • 2018
  • The purpose of this study was to examine the effects of hemispheric damage in body composition of male adults with stroke experiences. The Fourth and Fifth Korea National Health and Nutrition Examination Surveys (KNHANES) with body composition results obtained from the DXA (dual-energy X-ray absorptiometry) assessments were used for this study. Survey data of 18 post-stroke men and 28 healthy controls were obtained. Both the lean and fat masses of the upper and lower limbs were utilized to compare for the compositions between the limbs in post-stroke subjects. In addition, the effect of exercise habit was also observed for the influence of physical activity in body composition. Mixed results in left and right limb compositions were shown between the groups. When the subjects were further divided based on walking days per week, sedentary (walk ${\leq}2d/wk$) post-stroke group showed significantly greater fat mass and less lean mass than the physically active people (walk ${\geq}3d/wk$). In comparison to the healthy sedentary and physically active controls, two post-stroke groups showed greater variations. The results indicate that physical activity maintains or improve the quality of both the upper and lower limb composition in patients with post-stroke men.