• KSBB Journal
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• v.4 no.1
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• pp.40-47
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• 1989

Changes of principal components of crude green tea were determined after 30 min. of heat treatment at 10$0^{\circ}C$, l15$^{\circ}C$, 14$0^{\circ}C$, 16$0^{\circ}C$. Four kinds of free sugars(sucrose, fructose, glucose, raffinose) and an unidentified sugar compound were separated in green tea by using High Performance LiQuid Chromatography (H.P.L.C.). 26-34 peaks were isolated as aroma compounds of green tea by means of Gas Liquid Chromatography(G.L.C). The typical aroma component of green tea such as linalool, furfural, benzyl alcohol and 13 other substances were identified. Contents of most compounds were decreased by heat treatment. Especially contents of free amino acids, free sugars, vitamin C and tannins were decreased remarkably, while those of total nitrogen and soluble nitrogen were hardly changed. The effect of heat treatment on organoleptic quality of tea extracts were examined by sensory evaluation of which result indicated the most favorable tea was produced at 115$^{\circ}C$. The Percentages of loss in contents of total sugars, reducing sugars, vitamin C, free amino acids and tannins at 115$^{\circ}C$ were 17%, 16%, 36%, 12% and 15% respectively, while those were 38%, 53%, 55%, 74% and 23% at 16$0^{\circ}C$.

• Journal of the Mineralogical Society of Korea
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• v.15 no.1
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• pp.33-43
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• 2002

Mineral composition and chemical properties of Hwangto (reddish residual soil) that used in feeding of cattles at Iksan, Jeollabuk-do, Korea were examined according to particle size separation such as gravel, sand, silt, coarse clay and fine clay. Mineral composition analyses reveal that gravel and sand are mainly composed of quartz and feldspars and that kaolin mineral and illite are dominant in clay and silt. Iron oxides are mainly included in fine clay. According to chemical analyses of major elements, Al, Fe and $H_2O$ contents are increased with decreasing of particle size. This trend well agrees with increase of clay minerals in smaller particles, Chemical analyses of trace elements indicate that contents of Zn, Rb, Sr, Ba, Pb significantly differ with particle sizes. Ba and Sr are included in feldspars since these elements are abundant in sand containing abundant feldspars. Pb and Sm are abundant in sample before particle size separation, but the contents are significantly decreased after separation. Therefore, most of these elements appear to be existed as removable phase. Nb, La, Th, Ce are more abundant in silt. The contents of all the other trace elements tend to be increased in smaller particles containing more clay minerals. The contents of changeable cations and teachable elements in acid and alkali solutions are high in clay samples. All the above results indicate that using the portion of smaller particle of Hwangto for livestock feed rather than bulk Hwangto can improve cation exchangeable capacity, ion leaching capacity and sorption properties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.198-203
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• 1989

Field experiment was conducted to find out the effect of lime materials application on yield, and chemical composition of Burley 21 in 1986. Lime materials and application rate were CaSO$_4$ : Ca 35kg/l0a. CaCO$_3$ : Ca 35kg/l0a and Liming: pH6.5. Contents of Ca and Mg in fresh or cured leaves were increased, but AI, Fe and Mn were decreased by applying lime materials. Yield were increased by applying lime materials. Among lime materials treatment, yield of limed and CaCO$_3$ plot were higher than that of CaSO$_4$ plot. Value per kg of cured leaves was not affected by applying lime materials. Cured leaves of CaSO$_4$ plot contained higher NH$_3$-nitrogen and alkalinity number of water insoluble ash than those of unlimed plot. Cured leaves of CaCO$_3$, plot contained higher alkalinity number of water soluble ash, insoluble ash and volatile neutral constituent, but lower protein-nitrogen and petroleum ether extracts than those of unlimed plot. Cured leaves of limed plot contained higher alkalinity number of water soluble and insoluble ash, NO$_3$-nitrogen and volatile neutral constituents, but lower protein -nitrogen, nicotine and petroleum ether extracts than those unlimed plot. Yield was increased, however leaf Quality in respect to chemical and organoleptic characteristics were not affected considerably by applying lime materials. Therefore, it suggests that controlling the soil pH about 6.5 by liming might be necessary for tobacco cultivation.

• 한국문화재보존과학회:학술대회논문집
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• 2005.03a
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• pp.71-88
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• 2005

With biological organism brown pollutants layers are thickly formed on inner stone materials in Gyeongjuseokbinggo(Ice storage in Gyeongju). Some simples were taken from this layer and its chemical composition, mineral composition, salt and microstructures were analyzed. This study shows that the pollutants layer can be removed easily, because it attached softly in stone surface. But because of its serious weathering state the stone surface also can be removed during the removing process. The origins of brown layer are assumed to be the soil in the mound over the Seokbinggo and the coarse sandy soil in the entrance. For the preservation of the Seokbinggo Waterproof and replacement of the coarse sandy soil should take precedence over the remove works. Subsequently moistureproof works should be enforced.

• Journal of Conservation Science
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• v.26 no.3
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• pp.213-228
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• 2010

The composition of Chinese ceramic shards has been the subject of analysis in Europe, beginning in the 18th century, and in China from the 1950s. Scientific studies of traditional Korean shards commenced in the United States and Germany in the 1980s, and studies within Korea began in the 1990s. From analysis of a large systematically collected dataset, the composition of porcelain produced during the Kory. dynasty, including 21 celadon and 10 whiteware groups, was characterized and compared with that of Chinese ceramics. The average composition of the body and glaze of several shards (usually three to five) from each group was determined, enabling comparisons between groups. The results show that the majority of groups were derived from mica-quartz porcelain stone, which was commonly used in Yuezhou, Jingdezhen, and other southern Chinese kilns. The composition of glazes includes clay and flux components; the latter were typically wood ash and limestone, initially as burnt but later as crushed forms. The earliest of the Kangjin glazes contained substantially less titanium oxide than did the Yuezhou glazes, which were typically formulated from body material and wood ash. The present study provides a comparative framework for the growing number of analytical investigations associated with excavations occurring in Korea.

• Journal of the Korea Institute of Building Construction
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• v.16 no.6
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• pp.571-578
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• 2016

Recently, review on viability of various industrial by product and natural materials as raw material for concrete has been actively done in aspect of environment-friendly issue and depletion of natural resource. This study conducted fundamental study on the possibility of utilizing mud flat as admixture and filling material for concrete. First, chemical analysis on the viability of mud flat as admixture was done and the researchers compared it with the substance of fly ash and blast furnace slag. According to the result, substance content was proven to be inadequate. In addition, as the replacement rate of mud flat increased, compressive strength and tensile strength decreased. According to the estimated result of chemical substance analysis, possibility of utilizing mud flat as admixture was low. According to the result of experiment done as filling material, 10% ~ 30% replacement rate of mud flat manifested more than 8 Mpa of compressive strength of block which may be utilized for secondary product. However, additional experiment such as making block is required afterward. According to the result of flow experiment, as the replacement rate of mud flat increased, flow value decreased, and through chloride content analysis test, it was proven that mud flat is inappropriate to be applied as steel beam using structure since it has high content of sodium. It may be utilized as products that does not use steel beam such as internal brick.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.1-6
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• 2003

Chemical compositions of several herbs (rosemary, mint, thyme, sage, and lavender) cultivated in Korea were analyzed. Approximate compositions were as follows: moisture $69.92{\sim}82.10%$, crude ash $2.48{\sim}6.15%$, crude fat $0.40{\sim}2.46%$, crude protein $0.84{\sim}1.57%$, and crude fiber $2.48{\sim}6.15%$. Total contents of phenolics determined by Folin-Dennis's method were in the range of $73.24{\sim}197.79mg%$. Contents of minerals, Na, Ca, Mn, P, Mg, Zn, and Fe determined by ICP-AES were $43.0{\sim}112.5,\;177.5{\sim}304.0,\;0.5{\sim}1.5,\;74.0{\sim}218.5,\;57.0{\sim}116.0,\;1.0{\sim}2.0$ and $3.0{\sim}5.0mg%$, respectively. Free sugar contents determined by HPLC were: sucrose $0{\sim}7.61$, glucose $0.94{\sim}15.92$, and rhamnose $0.64{\sim}7.99mg%$. Fatty acids including palmitic, stearic, oleic, linoleic, linolenic, and arachidonic acids were identified by GC. Linoleic and linolenic acid contents were higher than those of palmitic and stearic acids. Aroma components identified by GC-MS were 1,8-cineole, ${\alpha}-phellandrene,\;{\alpha}-terpinene,\;{\beta}-pinene,\;{\beta}-thujone$, borneol, butan-1-ol, cis-sabinene hydrate, ${\delta}-carene,\;{\gamma}-terpinene$, and verbenone.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.230-231
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• 2004

경수로형 원자로의 증기 발생기 내부에 방사화 된 침적물을 smear paper로 시료를 채취한여 핵종 분석 및 화학조성을 분석하였다. 상용발전소의 증기 발생기 외부에서 발견된 고 준위 방사성물질의 화학 조성 분석은 극미세 성분분석기(EPMA)를 이용하였다. 본 시험에 사용한 EPMA(Electron Probe Micro Analyzer, SX-50R, CAMECA, Paris, France)는 고 방사능을 띤 조사 핵연료 및 재료 시험을 수행할 수 있도록 기기의 시편 stage 주위를 납과 텅스텐으로 차폐하여 시편의 방사능 세기가 $3.7{\times}10^{10}$ Bq까지 시험 가능한 기기이다.(중략)

• Analytical Science and Technology
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• v.10 no.5
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• pp.362-369
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• 1997

Chemometric technique was applied to the sugar composition in five honeys of known botanical or geographical origin following HPLC. Fructose and glucose were predominant carbohydrates in honeys, and small amount of sucrose was also detected in one sample. Sugar contents in honeys samples were compared by the geographical or botanical origin. Fructose/glucose ratio ranged from 0.99 to 1.55 was obtained and these results are in good agreement with the ratio of literature. The plot of principal components analysis(PCA) showed that different honey samples grouped into distinct cluster by the geographical or botanical origin. Increasing the first or second principal component score, higher amount of sugar or less fructose/glucose ratio was observed in PCA plot. Chemometric approach was very useful to provide pattern recognition of sugar profile or quality indices of honey sample and to detect adulteration.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.3
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• pp.138-147
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• 2006

In this study, the composition and physico-chemical characteristics of municipal solid waste (MWS) which was treated in national park area kyungnam-do landfill were investigated. It is necessary to measure the characteristics of MSW and sludge to build a waste treatment facility, the data-base and total managing of the landfill. This MSW was composed of 34.62% of food wastes, 36.05% of papers, 15.37% of plastics & vinyls, 2.28% of textiles, 3.33% of wood, 0.49% of rubber & leathers and others, respectively. Most of MSW are composed of food, paper and plastic waste and more than 90% was combustible waste. For three components, moisture is 29.84%, combustible component is 62.30% and ash is 7.86%. The chemical element has the high order of carbon, oxygen, hydrogen on the dry basis of wastes. Also, the low heating value of the MSW which is measured by calorimeter is calculated as 2377.8kcal/kg. low heating value of the sludge is calculated as 338.06kcal/kg.