• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.120.1-120.1
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• 2008

• 대한수의학회지
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• 제43권2호
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• pp.171-180
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• 2003

Certain hexavalent chromium compounds when administered via inhalation have the potential to induce lung injury in human and experimental animals. In present study, the inhalation effect of hexavalent chromium on morphological change and weight change of rat organ were investigated. Rats were exposed to hexavalent chromium ($Na_2CrO_4{\cdot}4H_2O$) at concentration of $0.36mg/m^3$ (group 1), $1.8mg/m^3$ (group 2), ascorbic acid and $1.8mg/m^3$ (group 3) and filtered air (group 0, control group) for I week, 2 weeks and 3 weeks. The weight of lung and kidney in group 2 and group 3 significantly higher than in control group at same exposure period. The epithilial cells of bronchiole in group 1, 2, 3 were more flatten than group 0. In the lung, the number of macrophage was significantly increased and morphologically changed macrophages were observed in group 1, 2, 3. The morphological change of the lung did not significant between group 2 and group 3, however, in group 1 was milder than in group 2 and group 3. The severity of morphological change were depend on exposure period in the lung. The morphological changes by hexavalent chromium of the liver and kidney were also observed These results suggest that inhalation of hexavalent chromium effects on not only respiratory organ, but also the liver and the kidney via blood stream.

• 환경위생공학
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• 제5권1호
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• pp.7-13
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• 1990

대구지방의 중요 하천인 낙동강, 금호강 및 신천을 대상으로 이들간의 수질차이와 홍수 전(8월24일)과 후(9월8일)의 수질차이를 비교하는 한편, 각 하천수가 Spirodela polyhiza Shleiden의 생육에 미치는 영향을 조사하였다. 홍수 전의 화학 성분 농도는 대부분 금호강과 신천이 서로 유사하며(COD, 19.6~21.4; alkalinity, 177~183; ${NH_4}^{+},\; 20.7~24.4;\;{NO_3}^{-}\;39~4.3;\;{PO_4}^{3-},\;3.4~3.7;Ca^{2+},\;68.5~69.7;\;Mg^{2+},\;42;\;Cl^{-},\;90~92;SiO_2, \;10.4~11.2;\;{SO_4}^{2-},\;11~32;\;LAS,\;3.0~3.8;\;Cr^{3+,6+}$, 0.007~0.010ppm), 낙동강에 비해 훨씬 높았다.(${NH_4}^{+},\;{SO_4}^{2-},\;{PO_4}^{3-}$ 및 LAS는 30~40배 : COD, alkalinity,${NO_3}^{+},\;Mg^{2+},\;Cl^{-}$ 및 $Cr^{3+,6+}$은 2~5배). 특히 금호강은 다른 하천과는 달리 Secchi disk transparency가 극히 낮고(17cm), DO가 검출되지 않았다. Phytoplankton 군집의 general diversity index($\bar{H}$)는 낙동강, 금호강 및 신천이 각각 3.1, 2.7 및 1.6으로 신천의 오염도가 가장 높았다. 홍수기 후에는 특히 다음과 같은 성분이 증가하였다.(낙동강-${NH_4}^{+},1.0;\;{NO_3}^{-},9.6;\;SiO_2,\;12.8;\;{SO_4}^{2-}\;5.4ppm$; 금호강 DO, 1.0;${NO_2}^{-},\;0.92;\;{NO_3}^{-},\;22.2;{SiO_2},\;17.6ppm$; 신천-DO, 3.0;${NO_2}^{-},\;1.4;\;{NO_3}^{-},\;22.2;{SiO_2},\;19.2;{SO_4}^{2-}\;25ppm$). S.polyrhiza의 생육은 금호강수에서 가장 왕성한 반면(최대 RGR, 26%/day), 금호강수에서는 배양 7일째 생장이 중지되었고, 배양 11일째의 total chlorophy 일 함량은 낙동, 금호 및 신천수에서 각각 1.04, 1.88 및 1.25mg/g frond였다. 이들 하천수에 함유된 LAS(0.1~3.8ppm), $Cd^{2+}$(0~0.02ppm) 및 $Cr^{6+}$(0.004~0.010ppm)은 이 식물의 생육을 크게 저해하지 않았다.

• 한국지구과학회지
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• 제27권1호
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• pp.49-60
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• 2006

본 연구는 나주지역 하상퇴적물에 대한 지구화학적 특성 연구이다. 이를 위해 1차 수계를 대상으로 139개의 하상퇴적물 시료를 채취하였다. 채취된 시료는 실험실에서 자연 건조시켰으며, XRF, ICP-AES, NAA를 이용하여 화학분석을 실시하였다. 기반암에 따른 지구화학적 특성을 알아보기 위하여, 화강암질편마암 지역, 편암류 지역, 화강암류 지역, 사질암 지역, 응회암 지역, 안산암 지역, 유문암 지역으로 분류하였다. 나주지역 하상퇴적물의 지질집단별 주성분원소 평균함량은 $SiO_2\;58.37{\sim}66.06wt.%,\;Al_2O_3\;13.98{\sim}18.41wt.%,\;Fe_2O_3\;4.09{\sim}6.10wt.%,\;CaO\;0.54{\sim}1.33wt.%,\;MgO\;0.86{\sim}1.34wt.%,\;K_2O\;2.38{\sim}4.01wt.%,\;Na_2O\;0.90{\sim}1.32wt.%,\;TiO_2\;0.82{\sim}1.03wt.%,\;MnO\;0.09{\sim}0.15wt.%,\;P_2O_5\;0.11{\sim}0.18wt.%$이다. 주성분원소의 평균함량 비교에서 $Al_2O_3$와 $K_2O$는 화강암질편마암 지역에서, $Fe_2O_3,\;CaO,\;P_2O_5$는 응회암 지역에서, MgO와 $TiO_2$는 안산암 지역에서, $Na_2O$는 유문암 지역에서 높고, $SiO_2$와 MnO 함량은 사질암 지역에서 약간 높다. 미량성분 및 희토류원소의 지질집단별 평균함량은 $Ba\;1278{\sim}1469ppm,\;Be\;1.1{\sim}1.5ppm,\;Cu\;18{\sim}25ppm,\;Nb\;25{\sim}37ppm,\;Ni\;16{\sim}25ppm,\;Pb\;21{\sim}28ppm,\;Sr\;83{\sim}155ppm,\;V\;64{\sim}98ppm,\;Zr\;83{\sim}146ppm,\;Li\;32{\sim}45ppm,\;Co\;7.2{\sim}12.7ppm,\;Cr\;37{\sim}76ppm,\;Cs\;4.8{\sim}9.1ppm,\;Hf\;7.5{\sim}25ppm,\;Rb\;88{\sim}178ppm,\;Sc\;7.7{\sim}12.6ppm,\;Zn\;83{\sim}143ppm,\;Pa\;11.3{\sim}37ppm,\;Ce\;69{\sim}206ppm,\;Eu\;1.1{\sim}1.5ppm,\;Yb\;1.8{\sim}4.4ppm$이다. Pb, Li, Cs, Hf, Rb, Sb, Pa, Ce, Eu, Yb 평균함량은 화강암질편마암 지역에서, Ba, Co, Cr 평균함량은 편암류 지역에서, Nb, Ni, Zr 평균함량은 사질암 지역에서, Sr 평균함량은 응회암 지역에서 높고, Be, Cu, V, Sc, Zn 평균함량은 안산암 지역에서 다른 지질집단에서 보다 높다.

• 한국환경보건학회지
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• 제25권3호
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• pp.64-69
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• 1999

This study was carried out the removal of Cr(VI) which was known to the toxic pollutant in industry using the process of UV and TiO$_2$ photocatalyst in a circular type reactor. In this experiment, the series of photocatalytic process for the removal of Cr(VI) has been selected as a model reaction in a circular type reactor in order to obtain the basic data on the influence of various experimental parameters such as circulation flow rate, pH of solution, initial Cr(VI) light illumination and TiO$_2$ dosage, and salicylic acid concentration. The results of this study were as follows; 1. With both UV light illumination and TiO$_2$ present, Cr(VI) was more effectively eliminated than with either UV or TiO$_2$ alone. 2. As the circulation flow rate of solution increased, the removal efficiency of Cr(VI) was increased. However, over 2.4 l/min of circulation flow rate, the efficiency wa limited. 3. A increase in the photocatalytic removal of Cr(VI) was noticed with decreasing pH. 4. An increase in the photocatalytic removal of Cr(VI) was noticed with decreasing Initial Cr(VI) concentration and first order kinetics was observed from the result at different initial concentration of Cr(VI). 5. Photocatalytic removal efficiency of Cr(VI) increased with increasing TiO$_2$ dosage. However, over 1.0 g/l of TiO$_2$ dosage, the efficiency reached a plateau. 6. As low concentration of saliculic acid were added, there was an increase in the removal efficiency of Cr(VI). However, over 300 mg/l of salicylic acid, the efficiecy was decreased. It eas found that application of photocatalysis to water treatment that contains both Cr(VI) and salicylic acid was possible.

• 암석학회지
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• 제27권1호
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• pp.37-47
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• 2018

백두산에서 역사시대에 분화한 화산재의 시료에 대하여 다양한 방법으로 주성분과 미량성분을 분석하였다. 화산재의 주성분 원소 함량은 $SiO_2$ 58.8~71.1 wt.%, $Al_2O_3$ 9.6~16.8 wt.%, ${Fe_2O_3}^T$ 4.5~6.9 wt.%, MgO 0.1~1.7 wt.%, CaO 0.3~1.6 wt.%, $Na_2O$ 5.2~6.3 wt.%, $K_2O$ 4.3~5.9 wt.% 그리고 $TiO_2$ 1.2 wt.%이하로 분석되었다. Ba, Cu, Cr. Co, Ni, Sr, V, Zn와 Zr을 포함하는 32개 미량원소가 분석되었는데, 이들 화산재는 일부 미량원소와 경희토류 원소의 부화정도에 따라 두 그룹(그룹 A, 그룹 B)으로 구분되며, 그룹 A에는 1천년 전의 밀레니엄 분화물, 1668년과 1903년 분화물이, 그룹 B에는 1702년 분화물이 해당된다. 중금속원소인 Cu, Co, Zn, Mn 등은 소량 함유되어 나타난다. 백두산 화산재는, 섭입대 기원의 일본 사쿠라지마 화산의 화산재와 비교하여, 미량성분원소 중 Y, Nb, Pb, U, Sc, V, Ni 그리고 Cu 함량은 낮게 나타나며, Zr, Ba, Hf, Cr, Co, Zn 그리고 희토류(Eu제외) 등은 높은 함량을 나타낸다.

• 한국의학물리학회지:의학물리
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• 제16권4호
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• pp.202-206
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• 2005

Magnesium Aluminum Spinel ($MgAl_2O_4$)은 자외선 선량계에로 응용성을 가지고 있는 Aluminum oxide와 유사한 물리 화학적 특성을 가지고 있다. $MgAl_2O_4$의 자외선 선량계로 응용하기 위한 열자자극발광 특성을 조사하였다. 자외선 조사된 $MgAl_2O_4$의 3차원 열자극발광 스펙트럼을 300${\~}$600 K 및 300${\~}$800 nm 범위에서 측정하였다. 자외선 조사시간의 증가함에 따라 열자극발광 곡선의 정점 온도는 낮은 쪽으로 이동하였다. 476 K 정점의 열자극발광 곡선은 second-order kinetics이고, 활성화 에너지 및 이탈진동수는 각각 0.85 eV 및 $1.92{\times}10^6\;sec^{-1}$이다. 열자극발광 스펙트럼은 530 nm 및 700 nm 방출 스펙트럼으로 나눠지고, 이들은 각각 $V^{2+}$와 $Cr^{2+}$에 포획된 양공에 기인한다. 700 nm 열자극발광의 선형성이 530 nm 보다 작은 반면, 700 nm 열자극발광의 포화는 530 nm 보다 더 많은 조사시간에서 나타난다.

• 보존과학연구
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• 통권22호
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• pp.93-114
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• 2001

The composition analysis of Danchung pigments at Geunjeongjeon Hall in Gyeongbokgung Palace were carried out by FXRF and MXRD. The analytical result of the inside pigments at Geunjeongjeon showed that these painted in use the mineral pigments. Gold pigment was pure gold(Au).The main composition identified in green pigments were chalcanthite($CuSO_4$.$5H_2O$) and celadonite($K(Mg, Fe, Al)_2$.$(Si, Al)_4O_10(OH)_2$ ). Red pigments werecinnnabar(HgS).The analytical result of the outside pigments at Geunjeongjeon revealed that these applied to the artificial synthetic pigment. Yellow pigment was chromeyellow($PbCrO_4$). The main composition identified in red pigments were red lead($Pb_3O_4$)and hematite($Fe_2O_3$). Green pigments were emeral green($C_2H_3A_s3Cu_2O_8$) and chromegreen($Cr_2O_3$). Blue pigment was lazurite($Na_6Ca2Al_6Si_6O_24(SO_4)_2$), titanium dioxide($TiO_2$) of white pigment.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1260-1266
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• 2001

The effect of protein supplementation, $O_2$ concentration and co-culture on the development of embryos produced by nuclear transfer using cultured cumulus cell was investigated. Recipient oocytes and cumulus cells were obtained from the ovaries of the slaughtered Hanwoo cows. Donor cumulus cells were cultured in Dulbecco's modified Eagle medium containing 10% fetal bovine serum at 5% $CO_2$ in air at $38.5^{\circ}C$. The 1 to 6 passages of cumulus cells were isolated and used as donor cells. The in vitro matured oocytes were enucleated and then the isolated donor cells were introduced. One $15{\mu}s$ pulse of 180 volts was applied to induce the fusion between karyoplast and cytoplast. The fused embryos were activated with $10{\mu}M$ calcium ionophore for 5 min and 2 mM 6-dimethylaminopurine for 3 h. To examine the effect of protein supplementation, nuclear transfer (NT) embryos were cultured in one of the following 4 treatments : 1) CR1aa + 3 mg/ml BSA for 7 days ; 2) CR1aa + 10% FBS for 7 days ; 3) CR1aa + 1.5 mg/ml BSA + 5% FBS for 7 days ; and 4) CR1aa + 3 mg/ml BSA for first 3 days and then CR1aa + 1.5 mg/ml BSA + 5% FBS for 4 days. Culture took place at 5% $CO_2$, 5% $O_2$ and 90% $N_2$ at $38.5^{\circ}C$. Although there were no significant differences in cleavage rate among different protein supplements, the rates of blastocyst formation were significantly different. When NT embryos were cultured in the medium supplemented with only BSA, they could develop to only morula not to blastocyst. However, when FBS was supplemented, NT embryos developed to blastocyst stage. In order to investigate the effect of $O_2$ concentration and co-culture, NT embryos were cultured in CR1aa + 1.5 mg/ml BSA + 5% FBS with or without cumulus cell co-culture at an atmosphere of 5% $CO_2$ in air (20% $O_2$) or 5% $CO_2$, 5% $O_2$, 90% $N_2$ (5% $O_2$) at $38.5^{\circ}C$ for 7 days. The percentage of blastocyst development was significantly higher when the NT embryos were cultured at an atmosphere of 5% $O_2$ than that of 20% $O_2$ (p<0.05). However, there was no significant difference between with and without cumulus cell co-culture at an atmosphere of 5% $O_2$ or 20% $O_2$. Fifty embryos were transferred to 25 recipients and 5 recipients were pregnant at 100 days. From 5 pregnant cows, only one cow was delivered of female twin. In conclusion, the embryos reconstructed by enucleation of metaphase II oocytes and introduction of the cycling and quiescent cumulus donor cells in Hanwoo had developmental potential to term after embryo transfer to recipient cows.

• Environmental Engineering Research
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• 제8권1호
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• pp.22-30
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• 2003