• KSBB Journal
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• 제15권2호
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• pp.208-213
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• 2000

백자, 청자 및 일반 자기 제조용 점토인 3종류의 점토(백토, 청토, 황토)를 철환원 미생물을 이용한 숙성과정을 통해 점토의 개질을 수행하였다. 철환원 미생물을 이용한 숙성기간 동안 점토 종류에 따른 철환원 및 용출특성과 숙성된 점토들의 물성 변화를 조사하였다. 숙성기간동안 점토의 철용출량은 점토의 종류에 관계없이 탄소원인 sucrose의 첨가량이 증가할수록 증가하였지만, 총 철용출량과 용출속도는 점토의 종류에 의존하였다. 숙성점토는 원료물질과 비교하여 sucrose 의 첨가량이 증가함에 따라 수축을 변화없이 강도와 색도가 향상되었다. 점토의 색도는 점토의 종류에 많은 영향을 받았으며, 점토의 숙성과정은 색도 중 적색도가 가장 많이 감소하는 효과를 제공하였다. 숙성점토의 물리적 특성과 탈철양을 고려할 때, 점토 중에 함유된 철환원을 전자공여체로 제공되는 sucrose의 최적 첨가량은 4wt% 임을 확인하였다.

• 헤리티지:역사와 과학
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• 제36권
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• pp.267-297
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• 2003

The plain coarse pottery from the Unjeonri Bronze Age relic sites in the Cheonan, Korea were studied on the basis of clay mineralogy, geochemistry and archaegeological interpretations. For the research, the potteries are utilized at the analysis for 6 pieces of plain coarse potteries. Color of the these potteries are mainly light brown, partly shows the yellowish brown to reddish brown. The interior, surface and inside of the pottery appear as different colors in any cases. Original source materials making the Unjeonri potteries are used of mainly sandy clay soil with extreme coarse grained irregularly quartz and feldspar. The magnetic susceptibility of the Unjeonri pottery range from 0.20 to 1.20. And the Unjeonri soil's magnetic susceptibility agree almost with 0.20 to 1.30. In the same magnetization of soil and pottery, the results revealed that the Unjeonri soil and low material of pottery are same produced by identical source materials. The Unjeonri potteries and soil are very similar patterns with all characteristics of soil mineralogy, geochemical evolution trend. The result seems to be same relationships between the behavior and enrichment patterns on the basis of a compatible and a incompatible elements. Consequently, the Unjeonri potteries suggest that made the soil to be distributed in the circumstance of the relic sites as the raw material are high in a greater part. In the Unjeonri soil, the kaolinite is common occurred minerals. However, in the Unjeonri pottery, the kaolinite was not detected in all broken pieces. The kaolinite was presumed to destroy crystal structure during the firing processes of over $550^{\circ}C$. The quartz is phase transition from ${\alpha}$-quartz to ${\beta}$-quartz at $573^{\circ}C$, but the Unjeonri pottery did not investigated any phase transition evidences of quartz. The chorite was detected within the mostly potteries and soils. As the results, the Unjeonri potteries can be interpreted by not experiencing a firing temperature over $800^{\circ}C$. The colloidal and cementing materials between the quartz and low materials during the heating did not exist in the internal part of the potteries. An any secondary compounds by heating does not appear within the crack to happen during the dry of the pottery. The hyphae group are kept as it is with the root tissue of an organic matters to live in the swampy land. In the syntheses of all results, the general firing condition to bake and make the Unjeonri pottery is presumed from $550^{\circ}C$ to $800^{\circ}C$. However, the firing condition making the Unjeonri pottery can be different firing temperature partially in one pottery. Even, the some part of the pottery does not take a direct influence on the fire.

• 자원환경지질
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• 제30권6호
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• pp.531-541
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• 1997

Unconsolidated sediments of Youngjong Island were investigated to consider the vertical distribution of clay minerals and their origin. At least three sedimentation units can be recognized by color, magnetic susceptibility, and pH. X-ray diffraction analysis of clay size fraction reveals that illite is the most abundant phase (52.06%), and chlorite (27.16%), kaolinite (16.92%), smectite (3.86%) occur next to it. Detailed XRD study suggests that illitic materials contain fairly large amount of ordinary muscovite derived from the mica schist in Youngjong Island and adjacent area. The relative amount of kaolinite and chlorite is less than those of samples from estuary mouth of several rivers that flow to Yellow Sea and South Sea. Especially smectite content of the present sample is much higher than those of estuary sediments. These indicate that the unconsolidated sediments of tidal-flat deposit in Youngjong Island are largely affected by marine influence and partly affected by sediment in influx from China. However, some degree of source of this unconsolidated sediments is inland origin from adjacent estuary sediment and in situ or nearby weathered materials.

• 한국세라믹학회지
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• 제25권6호
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• pp.685-693
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• 1988

From leaching of Korean native halloysite with hot sulfuric acid, active species of siliceous aluminosilicate are obtained as residue, which gives the mole ratio of SiO2/Al2O3 10 and substantially removes most acid-soluble impurities. By dissolving the residue in sodium hydroxide at an ambient temperature sodium silicate solution is prepared, this is used for zeolite synthesis as one of starting materials. In order to prepare zeolite Type 4A thereform, addition of a proper aluminum source is made so that the composition of the reactant materials may be of the following mole ratios : Na2O/SiO2=1.2-1.5, SiO2/Al2O3=1.8-2.0 and H2O/Na2O=34-45 By careful control of ageing time and temperature, subsequent crystal growth is induced into microfine zeolite 4A, which gives optimum particle size distributjion being suitable for detergent builder. The zeolite products thus obtained and highly competitive with those from the use of the refined clay in comparison of their calcium exchange capacity, whiteness and particle size distribution. The present method shows a marginal advantage over the existing procedures requiring neitherseparate purification nor calcinating otherwise necessary for the raw clay ores in use.

• 환경위생공학
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• 제14권3호
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• pp.71-79
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• 1999

The Hg, Cd, Cu, Mn, and Zn in bottom sediments of han river and their tributaries were analyzed to evaluate the seasonal variations of heavy metals. Leaching tests were also performed for estimation of availability of heavy metal retention in sediments. Sediments of Anyang stream showed the highest concentration of heavy metal in the sediment samples. Heavy metal concentration was heavily depended upon the heavy metal source of tributaries of han river and particle distribution. Clay and silt had higher concentration of heavy metals than very fine san and fine sand due to difference of retention capability of heavy metal. The highest concentration of heavy metal was observed in bottom sediments irrespective of sites investigated. Heavy metals and ignition loss showed positive relations, and higher relationships with p-value <0.01 were observed between copper and lead. copper and zinc, and depended on the pH condition of leaching test, and leachated fraction increased with decrease of the pH.

• 광물과 암석
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• 제35권4호
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• pp.397-407
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• 2022

황사 구성 광물의 지질학적 근원을 추적하기 위해, 발원지인 몽골 남부 고비사막 기반암의 광물학적 특성을 분석하였다. 황사 발원지 기반암은 고생대 화산암 및 화산쇄설성 퇴적암, 고생대 화강암류, 중생대 퇴적암으로 구성되어 있다. 고생대 화산암 및 퇴적암은 매우 치밀하게 고화 및 변형되어 산지를 형성하며, 중생대 백악기 퇴적암은 고생대 화산암 및 퇴적암으로 이루어진 산맥 사이의 분지를 충전한다. 고생대층 암석은 녹니석과 사장석 함량이 높고, 녹색편암상의 변성작용을 받았다. 중생대 퇴적암층은 녹니석이 드물고, 스멕타이트, 일라이트-스멕타이트 혼합층, 카올리나이트 등의 점토광물이 풍부하다. 고생대 화강암류에는 각섬석과 흑운모가 특징적으로 함유되어 있다. 발원지 기반암의 광물학적 특성과 비교하면, 황사는 고생대층과 중생대층 기원 쇄설물의 혼합물이나, 중생대 퇴적암에 더 가깝다. 점토 함량이 높고, 덜 고화된 중생대 퇴적암류는 잘 부스러져 침식되기 쉬운 실트질 표토가 되어 황사 광물 구성에 기여한다.

• 보존과학회지
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• 제28권4호
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• pp.353-366
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• 2012

이 연구에서는 완주 송광사 소조사천왕상의 제작기법을 해석하였으며, 소조토의 산지를 추정하여 동일재료로 보존처리 및 복원할 수 있는 기초자료를 확보하였다. 사천왕상에 사용된 소조토는 층위별로 다양한 재질적 특성을 나타냈다. 원소조토로 추정되는 초벌층과 중벌층은 성인적으로 동일한 토양이 사용되었으며, 마감층은 약간의 차이를 보였으나 거의 유사한 토양으로 확인되었다. 그러나 보수층은 모든 분석결과에서 원소조토와 재질특성이 일치하지 않았다. 감마선 촬영 결과, 사천왕상의 제작은 심목과 부목을 강선과 'ㄷ'자 꺽쇠, 못, 새끼줄 등으로 연결하여 뼈대를 형성하고, 이 위에 소조토를 조성한 것으로 나타났다. 소조토의 산지해석 결과, 추정산지 일대 토양은 마감층에 사용된 토양과 동일기원으로 나타나 보존처리용 재료로 적합할 것으로 판단된다. 이 결과는 소조상의 제작기법 연구에 기여할 것으로 기대된다.

• 보존과학회지
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• 제28권1호
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• pp.7-20
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• 2012

이 연구에서는 천안 쌍용동 용암유적에서 출토된 조선시대(15~17세기) 토기에 대한 재료과학적 특성과 원료의 산지를 해석하였다. 토기가마 폐기장과 공방지에서 수습한 토기시료는 회색 및 적색계열로 다양한 형태와 소성온도에 따른 굳기 차이가 있으나 대체로 유사한 기질특성을 보인다. 또한 모든 토기와 공방지 토양은 산출상태, 광물조성 및 지구화학적 거동특성이 상당히 유사하나, 유적지 주변에서 수습한 토양은 이들과 상이한 재료학적 특성을 가진다. 그러나 식질의 공방지 토양은 용암유적 조선시대 토기제작에 실제 이용된 원료점토로 판단된다. 이 용암유적 조선시대 토기 중 연질토기는 운모의 상전이 온도인 $900^{\circ}C$ 전후, 경질토기는 뮬라이트와 사장석의 생성과 소멸온도를 기준으로 $1,000{\sim}1,100^{\circ}C$의 소성온도를 경험한 것으로 해석된다.

• Geosciences Journal
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• 제22권6호
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• pp.989-1000
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• 2018

The provenance of the Central Yellow Sea Mud (CYSM) in the Yellow Sea has been attracted a great deal of attention over the last three decades, but a consensus is not yet reached. In this study, 101 surface sediment samples collected from the CYSM were investigated to determine provenance and transport mechanisms in the area using the clay minerals and major element components. The Huanghe sediments are characterized by higher smectite, but the Changjiang sediments are more abundant illite contents. Western Korean rivers contain more kaolinite and chlorite than do Chinese rivers. The Chinese rivers have higher $Fe_2O_3$, MgO, and CaO than the Korean rivers at the same $Al_2O_3$ concentration. Therefore, the clay minerals and major element concentrations can be useful indicator for the source. Based on our results, we suggest that the surface sediments in CYSM were composed mainly of Changjiang sediments, mixed a partly with sediments from the Huanghe and the western Korean rivers. Although the northwestern part of CYSM is proximate to the Huanghe, the contents of smectite and CaO were extremely low. It could be evidence that the Huanghe materials do not enter directly into the CYSM due to the Shandong Peninsula Front. Considering the oceanic circulation in the Yellow Sea, the Changjiang sediments could be transported eastward with the Changjiang Diluted Water and then mixed in CYSM via the Yellow Sea Warm Current (YSWC). Huanghe sediments could be provided by coastal currents (Shandong Coastal Current and Yellow Sea Coastal Current) and the YSWC. In addition, sediments from western Korean rivers might be supplied into the CYSM deposit via the Korean Coastal Current, Transversal Current, and YSWC.

• 농업과학연구
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• 제49권2호
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• pp.379-387
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• 2022

A large amount of the mineral nitrogen is necessary for crop growth. With the use of nitrogen fertilizers, agricultural yield has increased during the last few decades. However, at the same time, nitrate from the cultivated land can be a source of environmental pollution, especially in water systems. For nitrogen management, it is necessary to analyze the pattern of nitrogen movement in soil. In this study, nitrogen leaching in upland soils was evaluated using undisturbed lysimeters with different soil textures during sesame cultivation. The soil texture of the lysimeters was clay loam (Songjung series) and sandy loam (Sangju series) soils. Sesame was cultivated from May 25 to August 24 in 2020. The standard amount of NPK fertilizer (N-P₂O₅-K₂O = 2.9-3.1-3.2 kg·10 a^-1) was applied before sowing. The amount of nitrogen leaching was calculated by multiplying the nitrogen (NO₃-N + NH₄-N) concentration and the amount of water drained below 1.5 m soil depth. The water was drained through percolation into macropores in the clay loam lysimeter. In contrast, in the sandy loam lysimeter, water drained more slowly than in the clay loam lysimeter. There was a slight difference in the total amount of leachate during the cultivation period, but the amount of nitrogen leaching was high in sandy loam soil. During the sesame cultivation period, the amount of nitrogen leaching from clay soil was 5.64 kg·10 a^-1, and 10.70 kg·10 a^-1 for sandy soil. We found that there was a difference in leaching depending on the soil physical characteristics. Therefore, it is necessary to consider the characteristics of soil to evaluate the leaching of nitrogen.