• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.297-298
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• 2011

Metal/poly (4,4'-aminotriphen-ylene hexafluoroisopropylidenediphthalimide) (TP6F PI)/metal structure exhibited an electrically volatile phase transition with high (OFF) or low (ON) resistive states when voltage between electrodes swept. Here, we demonstrate a noble set-up in which holes are injected by photoelectron emission process during the voltage sweep instead of direct charge carrier injection via metal electrode, which enables direct investigation into changed electronic structures of TP6F PI both in ON and OFF states using photoemission spectroscopy methods. In the I-V measurement, TP6F PI shows a non-volatile behavior. In spectroscopic results, this non-volatile behavior is leaded from the structural modification of the O=C double bond in phthalimide of TP6F PI by hole injection.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.342-342
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• 2011

산화막은 반도체 공정 중 가장 핵심적이며 기본적인 물질이다. 반도체 소자에서 내부의 캐리어들의 이동을 막고 전기를 절연시켜주는 절연체로서 역할을 하게 된다. 실제로 제작된 산화막에서는 dangling bond 혹은 내부에 축적되는 charge들의 의해 leakage가 생기게 되고 그에 따라 산화막의 특성은 저하되게 된다. 내부에서 특성을 저하시키는 defect을 감소시키기 위해 Plasma Treatment에 따른 특성변화를 관찰하였다. 본 연구에서는 최적화 시킨 Flexible TFT제작을 위해 저온에서 Silicon Oxide로 형성한 Gate Insulator에 각각 N2O, H2, NH3가스를 주입 후 Plasma처리를 하였다. 특성화 시킨 Gate Insulator를 이용하여 MIS(Metal-Insulator-Semiconductor)구조를 제작 후 C-V curve특성변화, Dit의 감소, Stress bias에 따른 stability를 확인 하였다.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.546-550
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• 2014

Relative reactivity of various carbonyl and acid derivatives in MPV-type (Meerwein-Ponndorf-Verley) reduction with an DIBAL(F) model has been studied via DFT and MP2 methods. Free energies of initial adduct formation (-Gadd) of DIBAL(F) model and carbonyls are in the order of amide < ester < aldehyde < ketone < acid chloride; in the alan-amide adduct, the developed positive charge at carbonyl carbon is expected to be stabilized by amide resonance, but in the acid chloride adduct it is destabilized by inductive effect of chloride. However the TS barrier energies (${\Delta}G_{TS}$) for the MPV-type hydride reduction of the carbonyl adducts are in the order of aldehyde < ketone < acid chloride << ester < amide; presumably decreasing order of electrophilicity of carbonyl carbon at adducts, which is well correlated with experimental data. It is noted that the relative reactivity of carbonyl derivatives in MPV-type reduction with DIBAL(X) is not governed by the alan-adduct formation energies, but follows the order of electrophilicity of carbonyl carbon of transition states.

• Archives of Pharmacal Research
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• 제10권4호
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• pp.232-238
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• 1987

The molecular structure of naproxen determined by X-ray diffraction technique was refine to the final R-value geing 0.042. The compound was recrystallized from ethanol solution in monoclinic crystal system, space group $P2_1$ , with Z = 2, a = 13.375(5) $\AA$, b = 5.793(2) $\AA$, c = 7.914 $\AA$, $\beta$=93.91(3)$\AA$ and $d_{obs}$ = 1.26, $d_{calc}$ = 1.25 g/cm$^{3}$. The structure was solved by direct method and refined by block diagonal least squares procedure for 747 relfections (F .leq. 6.sigma.(F)). The molecules are connected by two intermolecular OH--O type hydrogen bonds.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2003년도 제46회 춘계 학술연구 발표회
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• pp.44-44
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• 2003

Protein disulfide isomerase (PDI) is not only an isomerase catalyzing the formation of native disulfide bond(s) of nascent peptide, but also a molecular chaperone assisting chain folding. We have already reported the structure of a cDNA (bPDl) encoding PDI from Bombyx mori and the function of PDI as foldase in assisting protein folding. (omitted)

• Bulletin of the Korean Chemical Society
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• 제28권6호
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• pp.936-940
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• 2007

The aminolyses of diphenyl phosphinic chloride (1) with substituted anilines in acetonitrile at 55.0 oC are investigated kinetically. Large Hammett ρ X (ρnuc = ?4.78) and Bronsted β X (βnuc = 1.69) values suggest extensive bond formation in the transition state. The primary normal kinetic isotope effects (kH/kD = 1.42-1.82) involving deuterated aniline (XC6H4ND2) nucleophiles indicate that hydrogen bonding results in partial deprotonation of the aniline nucleophile in the rate-limiting step. The faster rate of diphenyl phosphinic chloride (1) than diphenyl chlorophosphate (2) is rationalized by the large proportion of a frontside attack in the reaction of 1. These results are consistent with a concerted mechanism involving a partial frontside nucleophilic attack through a hydrogen-bonded, four-center type transition state.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.193-194
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• 2005

By the high-temperature pad conditioning process: The slurry residues in pores and grooves of the polishing pad were clearly removed. These clear pores and enlarged grooves made the slurry attack the oxide surface. The changed slurry properties by high-temperature pad conditioning process made the oxide surface hydro-carbonate to be removed easily.

• Bulletin of the Korean Chemical Society
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• 제13권1호
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• pp.32-36
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• 1992

The gas-phase pyrolysis reactions of 2-alkoxypyrimidines(II), 2-alkoxypyrazines(III), 4-ethoxypyrimidine(IV) and 3-ethoxypyridazine(V) are investigated theoretically using the AM1 MO method. These compounds pyrolyze in a concerted retro-ene process with a six-membered cyclic transition state (TS). The relative order of reactivity if (IV)>(II)>(III)>(V), which can be rationalized by the two effects arising from electron-withdrawing power of the aza-substituent: (ⅰ) Electron withdrawal from the C-O bond accelerates the rate and (ⅱ) electron withdrawal from the $N^1$-atom, that is participating in the six-membered TS, deactivates the reaction. We are unable to explain the experimental result of the greatest reactivity for pyridazine, (V), with our AM1 results. The reactivity increase accompanied by successive methylation of the ethoxy group, ethoxytert-butoxy, is due to a release of steric crowding in the activation process.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.60-60
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• 1995

새로운 혈소판 활성화인자 (PAF) 수용체 결합 저해활성 유효성분인 pinusolide ($IC_{50}$/=2.5$\times$$10^{-7}$M)와 arctigenin($IC_{50}$/=5.2$\times$$10^{-6}$M)을 측백엽(Biota orientalis)과 우방자(Arctium lappa)로부터 분리하여 이미 보고한 바 있다. PAF 수용체에 대한 구조활성 상관관계를 규명하고자 또한 용해도가 우수한 강력한 PAF 길항제를 개발하고자 이 길항제들의 유도체들을 다양한 유기화학반응을 이용하여 합성하였고 in vitro PAF receptor binding assay로 그 활성의 강도를 비교 검토하였다. 그 결과, lactone ring 부분은 unsaturated lactone이 saturated lactone보다 활성이 강하였고 ring이 개열되면 활성이 현저히 감소하였다. pinusolide 경우 exocylclic double bond 부분은 sp$^2$구조의 hydrophobic한 유도체가 활성이 강하였으며, methyl ester 부분은 hydrophobic한 유도체가 활성이 강하였다. Arctigenin의 경우 aromatic unit가 hydrophobic할수록 활성이 강하였다.

• 한국세라믹학회지
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• 제53권1호
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• pp.81-86
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• 2016

The effect of substrate rotation speed on the phase forming behavior and microstructural variation of 8 wt% yttria ($Y_2O_3$) stabilized $ZrO_2$ (8YSZ) coatings as a thermal barrier coating has been investigated. 8YSZ coatings with $100{\sim}200{\mu}m$ thickness were deposited by electron beam-physical vapor deposition onto a super alloy (Ni-Cr-Co-Al) substrate with a bond coating (NiCo-CrAlY). The width of the columnar grains of the 8YSZ coatings increased with increasing substrate rotation speed from 1 to 30 rpm at a substrate temperature range of $900{\sim}950^{\circ}C$. In spite of the different growth behaviors of coatings with different substrate rotation speeds, the phases of each coating were not changed remarkably. Even after post heat treatments with various conditions of the coated specimens fabricated at 20 rpm, only a change of color was noticeable, without any remarkable change in the phase or microstructure.