• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.183-188
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• 2012

A blue phosphorescent $Ir(dfpypy)_3$ (dfpypy:fluorinated pyridine-pyridine ligand) complex with meridional configuration has been synthesized by newly developed effective method and its solid state structure and photoluminescence are characterized. For this complex, mer-$Ir(dfpypy)_3$, the glass-transition and decomposition temperatures appear at $160^{\circ}C$ and $384^{\circ}C$ respectively in TGA and DSC experiments, which indicates that this complex has high thermal stability. In a crystalline structure, an average Ir-C bond length of mer-$Ir(dfpypy)_3$ is slightly longer than that of fac-$Ir(dfpypy)_3$, which assumed to be due to the weak trans-influence. The absorption and emission spectra are observed more red-shifted in mer-$Ir(dfpypy)_3$ than fac-$Ir(dfpypy)_3$. In addition, the former is readily oxidized than the latter in electrochemical behavior.

• 한국산학기술학회논문지
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• 제21권4호
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• pp.588-595
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• 2020

반도체 산업용 9N 이상의 초고순도 N₂, Ar 등 불활성 가스 제조를 위해 가스 정제공정에 사용되고 있는 Ni 촉매의 물성 평가 및 촉매적 특성을 확인하였다. 조성이 다른 원기둥 형태의 C1, 츄러스 형태의 C2의 두 가지 Ni 촉매에 대해 비교 평가를 진행하였다. Ni 촉매의 형상과 미세구조를 분석하기 위해 광학현미경과 FE-SEM을 이용하였으며, 조성 확인 및 물성을 분석하기 위해 EDS, XRD, 그리고 micro-Raman 분석을 이용하였다. 또한 Ni 촉매의 비표면적 및 촉매적 특성을 확인하기 위해 BET, Pulse Titration 분석을 진행하였다. 조성 분석결과, C1의 경우, 상대적으로 graphite가 불순물로 다량 포함되어 있는 것을 확인하였으며, C2는 C1에 비해 Ni의 함량이 높은 것을 확인하였다. 비표면적 분석 결과, C2의 비표면적이 C1보다 약 1.69배 정도 큰 것을 확인할 수 있었다. 촉매적 특성분석 결과, 상온에서 O₂와 CO 불순물 제거 정도가 C2가 우수함을 확인하였다. 따라서 반도체 산업용 초고순도 불활성 기체 제조를 위한 Ni 촉매로는 불순물이 적고, 비표면적이 크며, 상온에서 O₂와 CO 제거 성능이 우수한 C2가 적합함을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.169-170
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• 2008

In this study, low temperature sintering property of the $0.6TiTe_3O_8-0.4MgTiO_3$ ceramics with sintering adds were investigated for LTCC application which enable to cofiring with Ag electrode. $TiTe_3O_8$ mixed with $MgTiO_3$ to improve the temperature property. In the X-ray diffraction patterns, the columbite structure of $TiTe_3O_8$ phase and ilmenite structure of $MgTiO_3$ phase were coexisted in all specimens. In the case of SnO addition, the bulk density and dielectric constant were increased but quality factor was decreased with amount of SnO additions. The TCRF of the $0.6TiTe_3O_8-0.4MgTiO_3$+xwt%SnO ceramics were shifted to negative direction. The dielectric constant, quality factor and TCRF of the $0.6TiTe_3O_8-0.4MgTiO_3$ ceramics with 2.5wt% addition of SnO sintered at $830^{\circ}C$ for 1hr were 29.86, 35,800 GHz, -0.58 ppm/$^{\circ}C$, respectively.

• 대한수학회보
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• 제33권3호
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• pp.359-366
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• 1996

A linear map T from a Banach algebra A into a Banach algebra B is almost multiplicative if $\left\$\mid$ T(fg) - T(f)T(g) \right\$\mid$ \leq \in\left\$\mid$ f \right\$\mid$\left\$\mid$ g \right\$\mid$(f,g \in A)$ for some small positive $\in$. B.E.Johnson [4,5] studied whether this implies that T is near a multiplicative map in the norm of operators from A into B. K. Jarosz [2,3] raised the conjecture : If T is an almost multiplicative functional on uniform algebra A, there is a linear and multiplicative functional F on A such that $\left\$\mid$ T - F \right\$\mid$ \leq \in', where \in' \to 0$ as $\in \to 0$. B. E. Johnson [4] gave an example of non-uniform commutative Banach algebra which does not have the property described in the above conjecture. He proved also that C(K) algebras and the disc algebra A(D) have this property [5]. We extend this property to a derivation on a Banach algebra.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.771-773
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• 1988

The Mechanical strength and the electrical insulation properties of the Epoxy Resin vary with the formation of chemical reactions between Epoxy and curing agent. Therefore, to study their reactions is important for understanding the properties of the cured Epoxy. In this paper, to get the cured Epoxy having good electrical insulation property, it is studied the effects of the surrounding temperature during the cure process on the property of the cured Epoxy. In the experiment, Epoxy is cured with the surrounding temperature varied between -5[$^{\circ}C$] to 50[$^{\circ}C$]. As the results, it follows that the higher the temperature is, the faster the cross-link process is.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.297.1-297.1
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• 2007

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.852-854
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• 2003

CNT paste was fabricated by mixture of multi-walled carbon nanotubes (MWNT) powder, organic vehicles and inorganic binder. Then firing process was performed at different temperature under air and $N_{2}$ atmosphere. It was found that emission property of CNT paste was changed by firing temperature and time due to interaction between remained resins and CNT powder. We obtained good emission property from CNT paste treated at $350^{\circ}C$ for 10 min.

• Journal of applied mathematics & informatics
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• 제29권5_6호
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• pp.1603-1608
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• 2011

Let R be a ring with identity. If a, b, $c{\in}R$ such that a+b+c = 1, then the distributive laws from addition over multiplication hold in R, that is a+(bc) = (a+b)(a+c) when ab = ba, and (ab)+c = (a+c)(b+c) when ac = ca. An application to obtains, if A,B are idempotent matrices and AB = BA = 0 then there exists an idempotent matrix C such that A + BC = (A + B)(A + C), and also A + BC = (I - C)(I - B). Some other cases and applications are also presented.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 초전도 자성체
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• pp.17-20
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• 2002

The effects of relatively low lead content (0.2~0.3) on the 2223 phase formation and transport property of Bi-2223/Ag tapes have been investigated. The results show that lead contents have great impact on the phase assemblage of precursors, subsequently, on the phase formation and transport property of silver sheathed BSCCO-2223 tapes. Powders containing Pb=0.25 and Pb=0.3 resulted in the nearly identical $J_c$ values in fully processed tapes, but leaded to significant difference on the phase formation process. For the case of Pb=0.2, both low conversion fraction of 2212 to 2223 and low $J_c$ value were obtained in final reacted tape, which was probably due to lack of enough liquid phase to facilitate the phase transformation.

• 한국식품과학회지
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• 제20권3호
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• pp.317-325
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• 1988

농축대두단백으로 만든 두유를 여러 가지 정도로 가열 처리한 후 젖산균 5종을 각각 접종하여 두유의 가열처리가 젖산균의 생육과 산생성 그리고 대두요구르트의 관능성과 커드의 침전에 미치는 영향을 관찰하였다. 먼저 산생성을 보면 표준시료(비가열(非加熱)시료)에 비하여 $60^{\circ}C-10$분 또는 그 이상의 가열로 모든 균주에서 산생성이 촉진되었으며 그 촉진의 정도는 대체로 가열의 정도가 높을수록 점차적으로 증가하여 Streptococcus lactis를 제외한 4균주의 산생성이 $121^{\circ}C-1$분에서 가장 높았다. 그러나 생균수는 가열 처리로 큰 변화가 없었다. 대두젖산균 음료의 관능성에 미치는 영향을 보면 $95^{\circ}C-30$분 시료의 관능 성은 표준시료보다 현저하게 우수하였으나 $121^{\circ}C-15$분 시료의 관능성은 표준시료보다 현저하게 저조하였다. 한편 두유의 가열처리로 대두젖산균 음료의 침전이 지연디는 경향을 보였으며 특히 $121^{\circ}C-15$분의 가여로 침전이 현저하게 지연되었다.