• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1127-1134
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• 2002

Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutio ns of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle syntheses have been proposed.

• Elastomers and Composites
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• v.32 no.5
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• pp.295-301
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• 1997

The effects of filler types and compositions on the final properties such as tensile strength, % elongation, hardness, and specific gravity of chloroprene rubber were investigated. The fillers involved in this investigation were HAF-type carbon black, Mistron, and white clay, For each filler, the variation of filler compositions gave almost the linear effects on the all properties investigated. For a fixed filler composition, different filler types gave different influential strength on rubber properties. After linearlization of experimental data with respect to each filler composition, the simple linear addition of each property with respect to filler compositions was applied to predict the final properties of the filler included rubber systems. For the chloroprene rubber system including the fillers composed of Mistron(25phr)/HAF(20phr)/clay(35phr), the predicted properties were well in accordance with the experimental results. Similar results were obtained for other additives such as processing oil and accelerator.

• Progress in Superconductivity and Cryogenics
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• v.5 no.1
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• pp.27-30
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• 2003

The Bi2212 based HTS tubes with 4 different compositions, Bi:Sr:Ca:Cu = 2.0:2.0:1.0:2.0, 2.1:2.0:1.0:2.0,2.2:1.8:1.0:2.0 and 2.2:1.8.1.0.2:2 with 10% of SrSO$_4$ were studied. For tube fabrication the optimum range of melt temperatures and preheating temperature and time for mold were 105$0^{\circ}C$~110$0^{\circ}C$ and 55$0^{\circ}C$ for 30min respectively. The mold rotating speed was 1000rpm. Typical tube dimension was 30/24mm in outside/inside diameter and 60mm in length. A tube was annealed at 84$0^{\circ}C$ for 40 hours in oxygen atmosphere. The plate like grains more than 20${\mu}{\textrm}{m}$ were well developed along the rotating direction of mold regardless of initial chemical compositions. The specimen with Bi2212 composition exhibited $T_c$ of 83K while the specimen with other compositions are lower than 60K. The measured $I_c and J_c$ at 77K(B = 0T) in Bi2212 composition were about 80A and 266A/$\textrm{cm}^2$.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.435-437
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• 2003

In order to investigate processes and factors controlling the chemical and isotopic compositions of the Han River, seasonal studies were carried out. The North Han River was much lower in the concentrations of total dissolved solids (TDS), dissolved inorganic carbon (DIC) and major ions than the South Han River, but higher in $SiO_2$ concentration, $\delta$$^{34}$ $S_{so4}$ value and $^{87}$ Sr/$^{86}$ Sr ratio. This indicates that the chemical and isotopic compositions of the Han River were strongly controlled by the geology of their drainage basins: silicate rocks in the North Han River and carbonate rocks in the South Han River. The $\delta$$^{34}$ $S_{so4}$ values were relatively higher in the North Han River (5.90$\pm$1.46$\textperthousand$)) than in the South Han River (3.48$\pm$0.73$\textperthousand$). This implies that dissolved S $O_{4}$$^{2-}$ in the North Han River might be mostly derived from deposition of atmospheric sulfates, whereas in the South Han River from oxidation of sulfide minerals in the abandoned poly-metallic deposits and the coal-bearing sedimentary rocks distributed over the upstream as well as deposition of atmospheric sulfates. The $^{87}$ S $r^{86}$ Sr ratios in the North Han River were distinctly higher than those in the South Han River, reflecting water-rock interaction with different rock types.pes.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.527-530
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• 2003

• Journal of the East Asian Society of Dietary Life
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• v.16 no.2
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• pp.186-191
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• 2006

The purpose of this research was to study the chemical compositions of pork for crossbred pig (female, 198 days old $102{\sim}118kg$) that were fed with tangerine byproduct from pregnancy through the whole rearing period. The samples for this study consisted of the pork from give the number of control pigs not fed with tangerine byproduct($T_0$), and the pork from give the number of study pigs fed with 8% tangerine byproduct during the whole breeding period, from the early pregnancy through the young, growing and finishing periods ($T_1$). Backfat thickness of the crossbred pigs was significantly decreased by feeding tangerine byproduct (p<0.05). The proximate composition, minerals, total amino acid, saturated fatty acid vs. unsaturated fatty acid and vitamin $B_2$ contents of loins were not significantly different among $T_0\;and\;T_1$, (p>0.05). Although those differences were not significant statistically, the tangerine byproduct tended to increase the amount of vitamin $B_1$, and decrease the crude fat and cholesterol contents.

• Journal of Korean Society of Steel Construction
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• v.12 no.6
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• pp.649-659
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• 2000

In this study, the chemical compositions and mechanical properties of high tensile strength steel plates in accordance with their thickness are quantitatively estimated, that are steel plates SM570 to be purposed to use in building structure. Test results of steel plates SM570 are compared with those of steel plates SS400 and steel plates SM490 mostly using building structure. It is found that chemical compositions, carbon equivalent, parameter of welding crack susceptibility, yield strength, tensile strength, elongation, and impact strength have satisfied the prescribed value in KS code for all case of thickness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.381-385
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• 1998

Chemical components of Perillar semen and physico-chemical properties o Perillae semen oil were analyzed for the use as an edible oil. The proximate compositions of Perillae semen were 7.5% moisture, 33.2% crude fat, 16.3% crude protein, 2.8% crude ash, 6.5% crude fiber, and 33.7% nitrogen free extract. The major amino acids of Perillae semen were glutamic acid(66.9mg%), aspartic acid (32.5mg%), histidine(21.6mg%), and phenylaanine (20.1mg%). The ratio of essential/total amino acid was 41.3%. The physico-chemical properties of the seed oil were 0.915 specific gravity, 1.4808 refractive index, 3.6 acid value, 181.7 iodine value, and 194.0 saponification value. Composition of major lipid of the oil fractionated by silicic acid chromatography was 94.2% neutral lipids and 5.8% polar lioids. The major fatty acids of the oil were linolenic, linoleic and oleic acid. Neutral lipids consisted of 59.9% linolenic acid, 15.6% oleic acid, 6.6% palmitic acid, and 2.5% stearic acid. Polar lipids consisted of 58.5% linolenic acid, 18.1% linoleic acid, 12.7% oleic acid, 7.7% palmitic acid, and 3.0% stearic acid.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.2
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• pp.1-14
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• 1991

In growing single crystals, which exhibit incongruent melting behavor, it is extremely difficult to maintain the stoichiometry of its chemical compositions for given crystals. For instance, $LiNbO_3$ is a typical one which exhibits such incongruent melt, especially with a large solid solution region that makes it difficult to maintain the chemical compositions. Such a variation can then cause a serious problem for the practical applications in designing a precision electro /optic device. Of the known methods of determining its composition and quality, an optical technique of measuring refractive index of the crystals has been implemented. This technique is also capable of determining optical uniformity of the grown crystals and the chemical compositions. The technique used for such characterizations is herein described and some of results are discussed.

• 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.