• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.801-802
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• 1992

Poly Si TFTs have been fabricated from low temperature annealed a-Si films. I-V and C-V characteristics in the off-state region were measured. Analytical model for the leakage current in the off-state was suggested. In the measurement, capacitance increased abruptly with Increasing gate and drain voltage. This phenomena is attributed to the leakage current.

• Archives of Pharmacal Research
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• 제19권6호
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• pp.497-501
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• 1996

A gene coding for triosephosphate isomerase (TPI) from a rat skeletal muscle cDNA library was cloned and its nucleotide sequence was determined. The 1, 348-bp cDNA clone contains 24 bp $5^I$ noncoding region, the entire 750 bp coding region corresponding to a protein of 249 amino acids, $547bp 3^I$ noncoding region and part of a poly(A) tail. It also contains a polyadenylation signal, AATAAA, starting from 17 bp upstream of the poly(A) tail. The calculated molecular weight of rat TPI is 27.8 kDa and the net charge is +4. The deduced amino acid sequence from rat TPI CDNA sequence has 93% and 94% homology with that of mouse and human clones, respectively. The amino acids at the residue of Asn12, Lys14, His96, Glu 166, His96, His101, Ala177, Tyr165, Glu13O, Tyr2O9, and Ser212 in catalytic site are completely identical, confirming that the functional residues in TPI proteins are highly conserved throughout evolution. The most profound characteristic of rat TPI enzyme, compared with other TPIs, is that there are five cysteine substitutions at the residue of 21, 27, 159, 195 and 204. A Glu123 instead of Gly was found in rabbit, rhesus, mouse and human sequences. Through the method of RT-PCR, the mRNA transcription level of TPI gene was found to be different among various tissues and was highest in muscle.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.36-39
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• 2002

Polycrystalline silicon (poly-Si) thin film transistor (TFT) technology is emerging as a key technology for active matrix liquid crystal displays (AMLCD), allowing the integration of both active matrix and driving circuit on the same substrate (normally glass). As high temperature process is not used for glass substrate because of the low softening points below 450$^{\circ}C$. However, high temperature process is required for getting high crystallization volume fraction (i.e. crystallinity). A poly-Si thin film transistor has been fabricated to investigate the effect of high temperature process on the molybdenum (Mo) substrate. Improve of the crystallinity over 75% has been noticed. The properties of structural and electrical at high temperature poly-Si thin film transistor on Mo substrate have been also analyzed using a sputtering method

• 한국염색가공학회지
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• 제19권2호
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• pp.7-13
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• 2007

Photopolymerization of 2-hydroxyethyl methacrylate(HEMA), in the presence of ethyleneglycol dimethacrylate(EGDMA) and 1-Hydroxycyclohexyl phenyl ketone as crosslinker and photoinitiator, respectively, produced crosslinked poly-HEMA hydrogels. The hydrogels were colored by the exhaustion of vinylsul-phone-type reactive dyes. Good colorfastness to laundering was achieved when colored with C.I. Reactive Black 5. We investigated that the effect of coloration on the hydrophilicity and swelling properties of the films. More hydrophilic gel-surfaces were generated with in increase in coloration and crosslinking. Higher surface energy was observed with higher crosslinking level. The more rapid and higher water swellability of poly-HEMA gels after coloration may be resulted from a more opened gel structure by the easier hydration of the hydrophilic sulphonic acid groups of the reacted dyes in water.

• 한국미생물·생명공학회지
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• 제18권3호
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• pp.273-279
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• 1990

PHB 생산을 위하여 메탄올을 기질로 한 선별배지에서 토양, 하천수, 퇴비 등으로부터 분홍색 색소를 가지는 PHB 축적 facultative methylotroph를 분리하여, 균주의 특성을 검토하였다. 분리균주의 최적 생육조건과 PHB 축적을 위한 배양조건을 조사한 결과 균체의 생육은 메탄올 농도 1.0(v/v), 질소원인$ NH_4C$ 농도 1.0g/l, 즉 C/N ratio 13.2 일때 그리고 pH 7.0과'$30^{\circ}C$에서 가장 좋았으며, PHB는 C/N ratio가 50.8, 즉 메탄올 농도 1.0(v/v )$NH_4CL$ 0.26g/l 일때, 그리고 pH 6.0일 때 건조중량의 약 40까지 축적되었다. 고농도 메탄올에 의한 생육저해를 극복하기 위하여 기질을 간헐적으로 계속 공급해주는 fed-batch 배양을 시도한 결과 균체량은 14g/l, PHB 축척량은 5.5g/l까지 증가시킬 수 있었다. 생산된 PHB를 분리.정제하여 IR과 $^I H-NMR$로 구조를 분석한 결과 3-hydroxybutyric acid 의 homopolymer임이 확인되었다. 또한 균주의 pink-pigment를 추출하여 absorption spectrum를 조사하여 그 특성을 규명하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.1030-1033
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• 2003

This paper presents the deposition characterization of polycrystalline silicon films by the HWCVD(Hot-wire Chemical Vapor Deposition) method at low substrate($300^{\circ}C$). The filament temperature, pressure and $SiH_4$ concentration were determined to be a critical parameter for the deposition of poly-Si films. Series A was deposited under the conditions of $1380^{\circ}C$(Tf), 100 mTorr and $2{\sim}10%\{SiH_4/(SiH_4+H_2)\}$ for 60 min. Series B was deposited under the conditions of $1400{\sim}1450^{\circ}C$ (Tf), 30 mTorr and $2{\sim}12%$ for 60 min. The physical characteristics were measured by Raman and FTIR spectroscopy, dark and photoconductivity measurements under AM1.5 illumination.

• 대한화학회지
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• 제40권12호
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• pp.748-755
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• 1996

물과 요소 수용액에서 Poly(ethylene oxide)(PEO)의 구조 성질에 대한 온도의 효과를 보고한다. 물과 요소/물 혼합물 (요소 농도는 각각 0.2, 1, 2 M)에서 PEO에 대한 고유점도와 Huggins 계수의 값은 점도측정 방법에 의해 얻어졌으며, 이것을 물 구조 변화 관점에서 논의했다. 낮은 온도(22.deg.C이하)에서 PEO-물간 상호작용은 우세해 사슬은 펼쳐져있는 반면, 높은 온도(24.ang.C 이상)에서는 상호작용이 우세하지 못하고 사슬은 소수성 수화에 의해 어켜있게 된다. 즉, 온도가 상승함에 따라 PEO-물 상호작용은 우세하지 못하게 된다. 요소가 계에 가해짐에 따라 PEO사슬은, 우세하지 못한 PEO-물 상호작용으로부터 유발된 구조화된 물의 동요에 의해, 더 펼쳐지거나 거대해지게 된다. 고유점도 값에 대한 온도의 효과는 Arrhenius 행동을 나타낸다. 따라서 점성 흐름에 대한 활성화 에너지를 구해 논의하였다.

• Journal of Electrical Engineering and information Science
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• 제2권5호
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• pp.65-71
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• 1997

We present heterojunction solar cells with a structure of metal/a-Si:H(n-i-p)/poly-Si(n-p)/metal for the terrestrial applications. This cell consists fo two component cells: a top n-i-p junction a-Si:Hi cell with wide-bandgap 1.8eV and a bottom n-p junction poly-Si cell with narrow-bandgap 1.1eV. The efficiency influencing factors of the solar cell were investigated in terms of simulation an experiment. Three main topics of the investigated study were the bottom cell with n-p junction poly-Si, the top a-Si:H cell with n-i-p junction, and the interface layer effects of heterojunction cell. The efficiency of bottom cell was improved with a pretreatment temperature of 900$^{\circ}C$, surface polishing, emitter thickness of 0.43$\mu\textrm{m}$, top Yb metal, and grid finger shading of 7% coverage. The process optimized cell showed a conversion efficiency about 16%. Top cell was grown by suing a photo-CVD system which gave an ion damage free and good p/i-a-Si:H layer interface. The heterojunction interface effect was examined with three different surface states; a chemical passivation, thermal oxide passivation, and Yb metal. the oxide passivated cell exhibited the higher photocurrent generation and better spectral response.

• The Korean Journal of Physiology and Pharmacology
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• 제8권5호
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• pp.253-257
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• 2004

Schwann cells play an important role in peripheral nerve regeneration. Upon neuronal injury, activated Schwann cells clean up the myelin debris by phagocytosis, and promote neuronal survival and axon outgrowth by secreting various neurotrophic factors. However, it is unclear how the nerve injury induces Schwann cell activation. Recently, it was reported that certain cytoplasmic molecules, which are secreted by cells undergoing necrotic cell death, induce immune cell activation via the toll-like receptors (TLRs). This suggests that the TLRs expressed on Schwann cells may recognize nerve damage by binding to the endogenous ligands secreted by the damaged nerve, thereby inducing Schwann cell activation. Accordingly, this study was undertaken to examine the expression and the function of the TLRs on primary Schwann cells and iSC, a rat Schwann cell line. The transcripts of TLR2, 3, 4, and 9 were detected on the primary Schwann cells as well as on iSC. The stimulation of iSC with poly (I : C), a synthetic ligand for the TLR3, induced the expression of $TNF-{\alpha}$ and RANTES. In addition, poly (I : C) stimulation induced the iNOS expression and nitric oxide secretion in iSC. These results suggest that the TLRs may be involved in the inflammatory activation of Schwann cells, which is observed during Wallerian degeneration after a peripheral nerve injury.

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2117-2124
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• 2013

The binding properties and sequence selectivities of ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ (bip = 4,4'-biphenylene (imidazo [4,4-f][1,10]phenanthroline) complexes with $poly[d(A-T)_2]$ and $poly[d(G-C)_2]$ were investigated using conventional spectroscopic methods. When bound to $poly[d(A-T)_2]$, a large positive circular dichroism (CD) spectrum was induced in absorption region of the bridging moiety for both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes, which suggested that the bridging moiety sits in the minor groove of the polynucleotide. As luminescence intensity increased, decay times became longer and complexes were well-protected from the negatively charged iodide quencher compared to that in the absence of $poly[d(A-T)_2]$. These luminescence measurements indicated that Ru(II) enantiomers were in a less polar environment compared to that in water and supported by minor groove binding. An angle of $45^{\circ}$ between the molecular plane of the bridging moiety of the ${\Delta}{\Delta}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex and the local DNA helix axis calculated from reduced linear dichroism ($LD^r$) spectrum further supported the minor groove binding mode. In the case of ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex, this angle was $55^{\circ}$, suggesting a tilt of DNA stem near the binding site and bridging moiety sit in the minor groove of the $poly[d(A-T)_2]$. In contrast, neither ${\Delta}{\Delta}$-nor ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex produced significant CD or $LD^r$ signal in the absorption region of the bridging moiety. Luminescence measurements revealed that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes were partially accessible to the $I^-$ quencher. Furthermore, decay times became shorter when bis-Ru(II) complexes bound to $poly[d(G-C)_2]$. These observations suggest that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes bind at the surface of $poly[d(G-C)_2]$, probably electrostatically to phosphate group. The results indicate that ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ are able to discriminate between AT and GC base pairs.