• Elastomers and Composites
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• 제48권3호
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• pp.209-215
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• 2013

가시광촉매를 이용하여 자동차 내장재에서 발생하는 VOCs의 저감 효과를 알아보았다. 가시광촉매는 sol-gel법으로 제조하였으며 UV-vis peak가 420 nm에서 적색이동 되어 가시광영역에서 감응하는 것으로 나타났다. 이러한 특성을 갖는 가시광촉매를 자동차 내장재에 코팅처리하고, 자동차 내장재에서 발생하는 VOCs를 측정한 결과 분해 저감율이 우수하게 나타났다.

• KIEE International Transactions on Electrophysics and Applications
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• 제11C권2호
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• pp.18-22
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• 2001

The thin films of high permitivity in ferroelectric materials using a capacitor are applied to DRAMs and FRAMs. (Ba, Sr)TiO$_3$ thin as ferroelectric materials were prepared by the sol-gel method and made by spin-coating on the Pt/Sio$_2$/Si substrate at 4,000 [rpm] for 10 seconds. The structural characteristics of the surface were analyzed by fractal dimension. The thickness of BST ceramics thin films was about 260∼280 [nm]. The property of the leakage current was stable with 10-9∼10-11[A] when the applied voltage was 0∼3[V]. BST thin films ha low leakage current properties when fractal dimension was low and a coating area was high.

• 한국결정성장학회지
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• 제9권5호
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• pp.493-497
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• 1999

솔젤법을 사용하여 광촉매 $TiO_2$ 분말체를 제조하였으며 제조조건으로서 R값(물/알콕사이드 몰비), 열처리 온도, 미세구조로서 결정상, 물성으로서 비표면적과 입자크기의 상관관계를 조사하였으며 기능성으로 수용액상 염료의 광표백반응에 적용하여 광분해능을 극대화하기 위한 최적조건을 결정하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.64-65
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• 2008

3D microbattery에 사용할 수 있는 $LiMn_2O_4$ 3차원 박막전극을 제조하여 그 전기화학적 특성을 관찰하였다. 3차원 구조의 형성을 위하여 먼저 polystyrene(PS) microsphere를 platinum이 증착된 Si/$SiO_2$ 기판위에 dip-coating 방식으로 코팅시켜 template로 사용하였다. 그 위에 sol-gel법을 이용, 박막을 형성시킨 후 template 를 제거하는 방식으로 $LiMn_2O_4$ 3차원 박막전극을 형성하였는데 이때 solution은 Lithium acetylacetonate[$LiCH_3CO-CHCOCH_3$], Manganese(III) acetylacetonate [Mn$(CH_3COCHCOCH_3)_3$]를 source 물질로 1-butanol과 acetic acid를 solvent로 활용하여 제조하였다.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.653-656
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• 2009

3-Dimensionally ordered macroporous $LiMn_2O_4$ thin film was prepared by a sol-gel and dip coating method on Pt/Ti/$SiO_2$/Si substrate. An opal structure consisting of mono dispersed polystyrene beads (300 nm) was used as a template. After solution containing Mn and Li precursors was coated on the template-deposited substrate, the template and organic materials in the precursors was removed by calcination at 400 ${^{\circ}C}$. And then the 3-dimensional $LiMn_2O_4$ thin film with spinel structure was fabricated by heat treatment at 700 ${^{\circ}C}$. The structural and electrochemical property was investigated by XRD, SEM and charge-discharge cycler.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.43-46
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• 2000

In this study, (Ba, Sr)$TiO_3$ (BST) ceramics thin films were prepared by Sol-Gel method. BST solution was made and spin-coated on Pt/$TiO_2$/Si substrate at 4000 [rpm] for 10 seconds. Coated specimens were dried at 150[$^{\circ}C$] for 5 minutes. Coating process was repeated 3 times and then sintered at 750[$^{\circ}C$] for 30 minutes. Structure and electrical characteristics of specimen was analyzed by Fractal Process. Thickness of BST ceramics thin films are about 2800[$\AA$]. Dielectric constant and loss of thin films was little decreased at 1[kHz]~1[MHz]. Dielectric constant and loss to frequency were 250 and 0.02 in BST3. The property of leakage current as the relation between the current and the voltage was that change of the leakage current was stable when the applied voltage was 0~3[V].

• 유변학
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• 제10권4호
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• pp.256-258
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• 1998

선형저밀도폴리에틸렌(LLDPE)의 필름 제조시 가공성 및 필름의 투명성을 개선하기 위한 실험을 하였다. LLDPE에 전자선을 조사하여 분자구조를 변형시켜줌으로써 가공 특성 및 광학적 특성이 향상된 필름을 얻을 수 있었다. 전자선 조사량의 세기를 조절하여 일정량만 조사하고 자외선 안정제를 소량 처방하면 필름 가공시 젤이 생기지 않았고 투명성 및 가공성이 개선되었다.

• BMB Reports
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• 제39권2호
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• pp.140-144
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• 2006

A deoxyriboendonuclease has been purified to near homogeneity from a fast growing mycobacterium species, M. smegmatis and characterized to some extent. The size of enzyme is about 43 kDa as determined by a denaturing gel analysis. It shows optimum activity at $32^{\circ}C$ in Tris-HCl buffer (pH 7.2) containing 2.5 mM of $MgCl_2$. Both EDTA and $K^+$ but not $Na^+$ inhibit its activity. Evidences show that the enzyme is not a restriction endonuclease but catalyzes the endonucleolytic cleavage of both the double- as well as the single-strand DNA non-specifically. It has been shown that the cleavage by this enzyme generates DNA fragments carrying phosphate groups at 5' ends and hydroxyl group at the 3' ends, respectively. Analysis reveals that no endonuclease having size and property identical to our deoxyriboendonuclease had been purified from M. smegmatis before. The property of our enzymes closely matches with the deoxyriboendonucleases purified from diverse sources including bacteria.

• 미생물학회지
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• 제18권3호
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• pp.133-147
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• 1980

Washed mycelia of Aspergillus nidulans FGSC159 were incubated in CMC minimal liquid medium and the culture filtrate which contained induced extracellular cellulase was fractionated by a three-step procedure including chromatography on Bio-Gel P-150, chromatography on DEAE-Sephadex A-50 and chromatography on Sephadex G-100. Three CMCase components ; F-I-Ia, F-I-Ib and F-II-Ia were prepared. No enzyme activity toward avicel could be detected in these components. Similarly, there was no ${\beta}-glucosidase$ activity. pH-optima of the three components were all 5.0 in acetate buffer. Temperature-optima for the activities of F-I-Ia, F-Ib and F-II-Ia were $45^{\circ}C,\;40^{\circ}C\;and\;50^{\circ}C$, respectively. F-II-Ia was shown to be more thermostable than the other two components. F-II-Ia was proved to have quite a different substrate specificity and action property and action property from those of F-I-Ia and F-I-Ib by product analysis on liquid chromatography.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.468-473
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• 1998

A mathematical model was developed for a continuous re-actor in which free radical polymerization of methyl methacrylate (MMA) occurred. Elementary reactions considered in this study were initiation, propagation, termination, and chain transfers to monomer and solvent. The reactor model took into account the density change of the reactor contents and the gel effect. A control system was designed for a continuous reactor using extended Kalman filter (EKF) based non-linear model predictive controller (NLMPC) to control the conversion and the weight average molecular weight of the polymer product. Control input variables were the jacket inlet temperature and the feed flow rate. For the purpose of validation of the control strategy, on-line digital control experiments were conducted with densitometer and viscometer for the measurement of the polymer properties. Despite the com-plex and nonlinear features of the polymerization reaction system, the EKF based NLMPC performed quite satisfactorily for the property control of the continuous polymerization reactor.