• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.707-708
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• 2010

• 대한치과의사협회지
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• 제8권3호
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• pp.273-277
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• 1970

• 자연과학논문집
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• 제14권2호
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• pp.33-40
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• 2004

유기물이 포함된 황산아연 폐수로부터 황산아연을 회수하기위해서는 유기물의 제거가 필수적이다. 폐수 속에 포함된 유기물을 2차 오염물질이 거의 발생하지 않게 처리하기 위하여 오전 산화법과 흡착법을 병용하여 처리함으로서 효과적으로 유기물을 제거 할 수 있었다. 과량의 황산은 산화아연을 처리하여 황산아연 7수염을 제조함으로써 과량의 황산을 처리할 수 있었다. 폐수 1kg을 처리하여 740g의 황산아연 7수염을 얻었다.

• 한국전기전자재료학회논문지
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• 제11권10호
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• pp.842-848
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• 1998

The stability of paraseodymium-based zinc oxide varistor consisting of Zn-Pr-Co-Cr-Y oxide was investigated according to yttria additives under different stress conditons, such as 0.8V\ulcorner\ulcorner/373K/12h and 0.85V\ulcorner\ulcorner/393K/12h. Wholly, all varistor after the stress showed nearly symmetric and stable I-V characteristics. Particularly, in the case of 2.0mol% and 4.0mol% yttria-added varistor showing a good I-V characteristics, the varation rate of varistor voltage were less 1% and that of nonlinear coefficient were about degree of 5%, and what is remarkable, leakage current with increasing stress time during the applied stress was almost constant. It the light of these facts, it is estimated that varistor constituents having 2.0mol% and 4.0mol% yittria, respectively, will be utilized to various application fields.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.151-157
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• 1991

The roles of temporary sealing materials used in endodontics are impotant Especially, its marginal sealing properties affect endodontic success and failure in endodontic treatment The purpose of this in vitro study was to compare and evaluate the marginal sealing properties of various temporary restorative materials used in endodontic access cavity by using electrochemical method. Standard endodontic access cavities were prepared in extracted human molar teeth and filled with Caviton, IRM, zinc oxide - eugenol cement. Each specimen was immersed in 1 % solution of KCl, and applied a potential of 9 V external power supply. Marginal microleakage and water sorption were measured for marginal sealing effect evaluation in comparison with each group. A comparative study of the obtained results have led to the following conclusions. 1. The Caviton group showed lower marginal microleakage value than the zinc oxide - eugenol cement and IRM group the 6 th day after. The IRM group showed lwoer marginal microleakage value than the zinc oxide - eugenol cement group from the 6 th day to the 12 th day. But there was no significant difference between zinc oxide - eugenol cement and IRM group after the 13 th day. 2. As time went by, marginal microleakage value was increased in Caviton, IRM and zine oxide - eugenol cement.

• 한국결정성장학회지
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• 제8권4호
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• pp.592-598
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• 1998

ZnO($Al_2O_3\;2%$ 2% doped) 산화물 타겟과 금속 Zn(Al 2% doped) 타겟을 사용하여 반응성 직류 마그네트론 스퍼터링법으로 산소 가스 및 인가 전력을 조절하면서 AZO(Aluminum doped Zine Oxide) 막을 증착하였다. 비저항과 평균 투과율을 고려할 때 최적의 투명전도성을 보이는 조건은 산화물 타겟의 경우 산소가스의 비가 $0.5{\times}10^{-2}~1.0{\times}10^{-2}$범위이며, 금속 타겟의 경우 인가전력 0.6kW에서는 0.215~0.227, 1.0kW에서는 0.305~0.315이었다. 각 최적조건에서 제막된 AZO 막의 비저항은 $1.2~1.4{\times}10^{-3} {\Omega}{\cdot}cm$cm으로 타겟에 의한 차이는 없었다.

• Restorative Dentistry and Endodontics
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• 제16권2호
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• pp.33-42
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• 1991

The purpose of this study was to evaluate the sealing properties of the temporary filling materials used in endodontic treatment Access cavities were prepared in 135 extracted human molar teeth. Then, cotton pellets were placed in the pulp chamber until the depth of 5 mm for the temporary filling materials; Caviton, zine oxide-eugenol, double sealing (A) (stopping 15 mm + zinc oxide - eugenol, 3.5mm ) double sealing (B) (stopping 3.0 mm + zinc oxide - eugenol 2.0 mm) and gutta percha stopping. After filling the materials, the teeth were immersed in 1 % methylene blue solutions for 3 days, 1 week and 2 weeks. Then thermal cycling was performed at the temperature of $60^{\circ}C$ and $4^{\circ}C$, followed by longitudinal sections on the center of tooth. Finally, staining on the cotton pellet was evaluated. The following results were obtained. 1. Stopping showed lower marginal sealing quality than Caviton, zinc oxide - eugenol and double sealing. 2. In 1 week group, Caviton showed higher marginal sealing quality than zinc oxide-eugenol, double sealing and stopping. 3. Caviton and double sealing (B) showed a great decrease in marginal sealing quality with the increse of time. 4. Caviton had high marginal sealing quality in 3 day group and 1 week group, but in 2 week group, Caviton showed a great decrease. 5. Double sealing (B) showed fairly high marginal sealing quality in 3 day group, but decreased greatly after 1 week on.

• 한국임상수의학회지
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• 제13권2호
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• pp.208-211
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• 1996

The left tusk of Asian elephant (Elephas maximus) was splitted longitudinally and its middle portion avulsed by slip. The pulp was exposed and bled. A loosened tusk fragment continued to irritate its sulcus. We performed a partial pulpotomy and pulp capping. We filled the wide space between the loosened tusk fragment and the counterpart with zinc oxide eugenol and zine phophate cement but it was failed, and then we fastened the loosened tusk fragment to the counterpart by gauze and plaster. The ollsened tusk fragment grew to drop 100 days after the insult and main portion with pulp capping was healthy.

• 자원리싸이클링
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• 제13권1호
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• pp.22-27
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• 2004

전기로제강분진을 환원휘발시켜 얻은 조산화아연을 염화암모늄용액으로 침출, 전해채취하여 99.9％(3-Nine) 이상의 고순도금속아연을 회수하기 위하여 침출용액 중의 Pb 및 Cd 불순원소이온들의 석출, 제거에 관한 기초실험을 수행하였다. Pb 및 Cd 이온 등의 석출, 제거는 금속아연분말의 첨가에 의한 cementation 반응을 이용하였으며, 정제된 용액을 전해액으로 사용한 전해채취실험을 수행하여 정액 중의 Pb 및 Cd 이온농도가 회수되는 금속아연 중의 Pb 및 Cd 함량에 미치는 영향을 분석하여 3N 이상의 고순도금 속아연 회수를 위한 정액조건을 조사, 검토하였다. Pb 및 Cd 이온농도가 각각 2ppm 및 0.1 ppm 이하인 정액을 전해액으로 사용할 때 3N 이상의 고순도금속아연을 회수할 수 있었으며, 이때 침출용액의 정액에 필요한 금속아연분말 첨가량은 8.5g/l 이상으로 조사되었다. 또한 정액과정에서 금속아연분말 첨가 시 용액의 Eh 변화를 측정하여 Eh 변화에 의한 금속아연분말첨가량의 제어가능성을 검토하였다.

• Restorative Dentistry and Endodontics
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• 제1권1호
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• pp.34-38
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• 1975

Artificial canals were prepared by means of engine reamer on the slab which was made of clear acrylic resin. The shape of this canal is similar to the natural canal, the size is almost same as Kerr File No. 70, and the length is about 20mm. Sealer, Zine oxide eugenol mixture was prepared as matched to spatula test. Lentulo filler was inserted as deep as middle portion and apical one-third portion of the canal and the dental engine was driven in the speed of 1,000 and 3,000 r.p.m. in 30 seconds and 60 seconds with feeding of the sealer. The author measured the excess flow of the canal sealer from Lentulo end. Following are the results obtained from this study. 1. Lentulo insertion at the middle portion 1,000 r.p.m. in 30 seconds case: 0.21mm Same as above in 60 seconds: 0.20mm 2. Lentulo insertion at apical-thirds. 1,000 r.p.m. in 30 seconds: 0.22mm. Same as above in 60 seconds: 0.20mm. 3. Lentulo insertion at middle portion. 3,000 r.p.m. in 30 seconds: 0.14mm Same as above in 60 seconds: 0.25mm. 4. Lentulo insertion at apical-thirds, 3,000 r.p.m. in 30 seconds: 0.11mm Same as above in 60 seconds: 0.27mm.