• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.148-151
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• 2004

The development of the gas separation processes using polymeric membranes has attracted a great deal of interest during the last two decades. Membrane in this application has to offer an excellent thermal stability, chemical/solvent resistance, and mechanical strength under operating conditions.(omitted)

• 한국산학기술학회논문지
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• 제15권2호
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• pp.1216-1221
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• 2014

PEIT는 옥수수와 같은 재생 가능한 자원에서 유래한 isosorbide monomer를 이용하여 bio-contents를 함유하고 있는 PET이다. 하지만 isosorbide contents가 향상될수록 기계적물성이 감소하는 단점이 있다. 본 연구에서는 우수한 기계적 물성을 가지고 있는 polycarbonate를 이용하여 PEIT의 단점을 보완하고, 또한 PEIT를 이용하여 PC의 인장신율 향상을 통해 성형가공성을 개선하고자 하였다. 이축압출기를 통해 제조한 PEIT/PC 블렌드에서 polycarbonate가 모폴로지, 유리전이온도거동, 열적안정성 및 기계적 물성에 미치는 영향을 확인하기 위해 FE-SEM, DMA, TGA, UTM 및 Izod impact tester를 통하여 분석을 수행하였다. 이로써 우수한 기계적 물성을 가진 polycarbonate는 PEIT와 상용성이 있음을 확인하였으며, 특히 PEIT25PC75 조성에서 열적 안정성 및 기계적 특성의 향상이 뛰어난 것을 알 수 있었다.

• Transactions on Electrical and Electronic Materials
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• 제5권6호
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• pp.233-236
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• 2004

Copper metallization has been used in high-speed logic ULSI devices instead of the conventional aluminum alloy metallization. One of the key issues in copper CMP is the development of slurries that can provide high removal rates. In this study, the effects of slurry chemicals and pH for slurry dispersion stability on Cu CMP process characteristics have been performed. The experiments of copper slurries containing each different alumina and colloidal silica particles were evaluated for their selectivity of copper to TaN and $SiO_{2}$ films. Furthermore, the stability of copper slurries and pH are important parameters in many industries due to problems that can arise as a result of particle settling. So, it was also observed about several variables with various pH.

• Elastomers and Composites
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• 제50권1호
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• pp.35-48
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• 2015

Polyhedral oligomeric silsesquioxane (POSS) is an important inorganic-organic hybrid material with a three-dimensional structure. Polyurethane (PU) is a widely applied polymer that has versatile properties with the change of two phase structure. When POSS is incorporated into PU by physical or chemical methods, many properties can be greatly improved, such as mechanical properties, thermal stability, biodegradation resistance, and water resistance. This paper reviews the recent progress in preparation, structure, and performance of POSS-modified polyurethane from the viewpoint of physical blending and chemical modification.

• 한국인쇄학회지
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• 제30권3호
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• pp.13-21
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• 2012

This study was carried out to evaluate the stability of archival documents produced using papers. The properties of archival documents depend on the type of fillers of papers that are used such as fiber, non cellulose fiber, and mineral. The physio-chemical characteristics of archival documents were analyzed by employing acid hydrolysis against cellulose fiber substances. Fibers of Korean hand-made (Hanji), flex, and cotten papers showed higher pH and the degree of polymerization (DP) than wood fiber and mechanical fiber. Mechanical pulp containing 12.8% of lignin showed the greatest decrease of DP due to acid hydrolysis, and this resulted in increase of degree of aging. The filler found to clay and talc did not contain metal such as $Fe^{+2}$, $Fe^{+3}$, and $Cu^{+2}$. The alkaline metals such as Mg, Ca, and Ti showed greater resistance to acid hydrolysis.

• 접착 및 계면
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• 제23권3호
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• pp.75-79
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• 2022

그래핀은 벌집 모양의 sp² 혼성 오비탈 결합으로 이루어진 이차원 탄소 동소체이다. 우수한 전기적, 기계적 특성을 보이며, 차세대 전자소자의 핵심 재료로써 각광을 받고 있다. 그러나, 소자를 구성하는 소재 간의 불안정한 계면 형성으로부터 쉬운 외부 불순물의 침투 혹은 흡착으로 인해 낮은 환경 안정성을 보이고 있다. 따라서 본 연구에서는 고체탄화수소를 그래핀의 전구체로 활용한 직성장을 통해 그래핀 기반 전계효과 트랜지스터의 낮은 환경 안정성을 해결하고자 한다. 직성장으로부터 합성된 그래핀은 이를 활용한 전자소자에서 전하 이동도 및 Dirac 전압의 변화 감소를 통해 높은 구동 안정성을 보였다. 이를 통해 차세대 전자소자의 핵심 재료로써 그래핀을 활용하기 위한 새로운 접근 방법을 제시하였다.

• 한국재료학회지
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• 제14권4호
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• pp.260-264
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• 2004

The problem of polyaniline (PANi) sensor has been poor mechanical and chemical stability under atmosphere condition. In order to overcome these problems, the PANi sensor coated with polyvinylidenefluoride ($PVF_2$) was employed. The morphology of $PVF_2$ coated-PANi layer was showed smooth and transparent properties at 15% concentration of coating solution. The resistance of $PVF_2$ coated-PANi was kept at constant value and had a good stability at long-term periods in presence of humidity.

• Journal of Mechanical Science and Technology
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• 제15권10호
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• pp.1451-1460
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• 2001

The critical condition of the onset of buoyancy-driven convective motion of uniformly heated horizontal fluid layer was analysed by the propagation theory which transforms the disturbance quantities similarly. The dimensionless critical time, $\tau$$\sub$c/, is obtained as a function of the Rayleigh number and the Prandtl number. Based on the stability criteria and the boundary-layer instability model, a new heat transfer correlation which can cover whole range of Rayleigh number was derived. Our theoretical results predict the experimental results quite reasonably.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.223-227
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• 2002

As the channel length of device shrinks below $0.13{\mu}m$, CMP(chemical mechanical polishing) process got into key process for global planarization in the chip manufacturing process. The removal rate and non-uniformity of the CMP characteristics occupy an important position to CMP process control. Especially, the post-CMP thickness variation depends on the device yield as well as the stability of subsequent process. In this paper, every wafer polished two times for the improvement of oxide CMP process characteristics. Then, we discussed the removal rate and non-uniformity characteristics of post-CMP process. As a result of CMP experiment, we have obtained within-wafer non-uniformity (WIWNU) below 4 [%], and wafer-to-wafer non-uniformity (WTWNU) within 3.5 [%]. It is very good result, because the reliable non-uniformity of CMP process is within 5 [%].

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1224-1226
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• 1999

When electrical engineers get started with the design of main electrical system of a complex petrochemical plant along with chemical and mechanical engineers, they are usually confronted with lack of power system data. This paper presents a procedure how to perform power system stability analysis for the purpose of design studies within the limited system data given and to verify the given data to get reliable convergence in dynamic simulation as well as to apply the stability analysis result on practical system design. The power system stability analysis on the Cadereyta petrochemical plant in Mexico is provided as a study case.