• KSBB Journal
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• 제7권3호
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• pp.191-200
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• 1992

토양 시료로부터A. tumefaciens를 분리 동정하고 이를 옥수수의 형질전환에 이용하기 위하여 binary vector를 이용하여 형질전환시킨 후 옥수수의 중배축 조직과 공존배양을 실시하였다. Schroth의 선택배지에서 선별된 colony들은 단일 형태를 나타내었다. 분리 균주는 해바라기 유식물의 잎조직에 종양을 형성하였으며, 거대 plasmid를 가지고 있었는데 이는 대조균주인 C58이나 Ach5의 plasmid와는 다른 종류였다. 분리균주들에 의해 형성된 tumor의 형태 및 균주의 생리, 생화학적 특성들에 의하여 공시균주를 A. tumefaciens biovar 1으로 동정하였으며 nopaline 형으로 추정하였다. 분리 균주중 AK204를 사용하여 옥수수 조직을 형질전환시키기 위하여 선택maker를 가지고 있는 binary vector(pGA642)를 균주내로 전이 시켰다. 이로 인하여 형질전환된 AK204를 옥수수 중배축 조직과 공존배양하므로서 옥수수 조직세포를 형질전환 시킨 결과, 1차적으로 Km에 저항성을 띠는 형질전환체를 선발할 수 있었으며, 그들의 가용성 단백질의 PAGE pattern이 변화되었음을 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.85-88
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• 2003

$Sr_xBa_{1-x}Nb_2O_6$(SBN, $025{\leq}x{\leq}0.75$) ceramic is a ferroelectric material with tetragonal tungsten bronze (TTB) type structure, which has a high pyroelectric coefficient and a nonlinear electro-optic coefficient value. In spite of its advantages, SBN has not been investigated well compared to other ferroelectric materials with perovskite structure. In this study, SBN thin film was manufactured by ion beam sputtering technique using the prepared SBN target in Ar/$O_2$ atmosphere. SBN30 thin film of 500 ${\AA}$ was pre-deposited as a seed layer on Pt(l00)/$TiO_2$/$SiO_2$/Si substrate followed by SBN60 deposition up to 4500 ${\AA}$ in thickness. SBN60/SBN30 layer was deposited at different Oxygen amount of 0, 8.1, 17, and 31.8 sccm, respectively. The crystallinity and orientation behavior as well as electric properties of SBN60/SBN30 multi-layer were examined. The deposited layer was uniform and the orientation was shown primarily along (001) plane from XRD pattern. The crystal structure and the electric properties depended on the Oxygen amount, heating temperature and was the best at O2 = 8.1 seem, $750^{\circ}C$. In electric properties of Pt/SBN60/SBN30/Pt thin film capacitor prepared, the remnant polarization (2Pr) value was 13 ${\mu}C/cm^2$, the coercive field (Ec) 75 kV/cm, and the dielectric constant 1492, respectively.

• 대한의용생체공학회:의공학회지
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• 제6권1호
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• pp.37-46
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• 1985

Development of a dental Ni-Cr alloy system for porcelain veneering crown and bridge was studied in this research. The principles of alloy design were a) It should not contain toxic beryllium. b) It should have low melting Point. c) It should be easily ground and polished. d) It should possess an adequate strength to resist the deformational force In the mouth. e) It should be bondable Ivith porcelain by chemically. After investigating the effect of minor elements such as boron and rare earth metals on the mechanical properties of the Ni-Cr alloy system, the compromised ideal composition for dental use was determined. The composition was l9.6%, Cr, 5.6% Mo, 3.4% Si, 1, 0% Fe, 0.01% Ti, 0.5-1.0% B, 0.2-0.6% misch metal, balance Ni. To compare the performance of experimental alloy with commercially available alloys, the properties such as strength, melting point, and bond strength were measured. The results Ivere as follows: a) Boron increases the strength of the alloy but reduces the elongation. b) Misch metal increases the strength when the boron content is low, but does not increase the strength when boron content is high. And it reduces the elongation drastically, c) Mechanical strength of the experimental alloy was not superior to commercially available Be containing alloy, but handling performance such as castability, ease of granting and polishing, and cuttability were superior to the Be containing alloy.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.271-274
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• 2003

[ $Sr_xBa_{1-x}Nb_2O_6$ ] (SBN, $0.25{\leq}x{\leq}0.75$) ceramic is a ferroelectric material with tetragonal tungsten bronze (TTB) type structure, which has a high pyroelectric coefficient and a nonlinear electro-optic coefficient value. In spite of its advantages, SBN has not been investigated well compared to other ferroelectric materials with perovskite structure. In this study, SBN thin film was manufactured by ion beam sputtering technique using the prepared SBN target in $Ar/O_2$ atmosphere. SBN30 thin films of different thickness were pre-deposited as a seed layer on $Pt(100)/TiO_2/SiO_2/Si$ substrate followed by SBN60 deposition up to $4500\;{\AA}$ in thickness. As-deposited SBN60/SBN30 layer was heat-treated at different temperatures of 650, 700, 750, and $800\;^{\circ}C$ in air, respectively, The crystallinity and orientation behavior as well as electric properties of SBN60/SBN30 multi-layer were examined. The deposited layer was uniform and the orientation was shown primarily along (001) plane from XRD pattern. There was difference in the crystal structure with heat-treatment temperature, and the electric properties depended on the heating temperature and the seed-layer thickness. In electric properties of Pt/SBN60/SBN30/Pt thin film capacitor prepared, the remnant polarization (2Pr) value was $15\;{\mu}C/cm^2$, the coercive field (Ec) 65 kV/cm, and the dielectric constant 1492, respectively.

• 식물병연구
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• 제12권3호
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• pp.205-212
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• 2006

2002년에서 2005년 동안 경북김천, 천안, 경기지역의 포도재배지로부터 채집한 300여점의 포도 혹병반으로부터 A. vitis의 PCR 특이검출 Phe A primer를 이용하여 포도혹병균의 대량분리를 실시하여 0.25kb의 PCR 특이밴드가 증폭된 51균주가 포도 혹병균으로 선발되었다. 이 균주들을 Ti-Plasmid 유래의 Vir A primer로 적용한 결과 40균주에서 0.5kb의 특이밴드가 검출되었다. 거봉포도와 당근절편에서 다양한 양상의 병원성을 보였으며 25균주가 거봉포도에 강한 병원성을 나타내었으며, 다른 균주는 약하거나 비 병원성을 보였다. 본 연구에서 분리한 10개 균주를 대상으로한 세균의 이화학적 특성은 균주간에 약간은 달랐으나, 3-Ketolactose의 비생성, 2%NaC 첨가 배지에서의 성장, Melezitose로부터의 산을 생성하지 못하는 등 비교균주와 대체적으로 일치하는 경향을 보였다. 따라서, PheA and Vir A primer를 이용하여 Agrobacterium vitis 균주를 대량 분리할 수 있으며 신속, 정확하게 동정할 수 있을 것으로 생각되었다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.118-121
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• 2007

Bulk metallic glass (BMG)/crystalline composites comprising a copper based BMG alloy and crystalline nickel were produced by means of eloctroless plating of nickel on $Cu_{54}Zr_{22}Ti_{18}Ni_6$ BMG powder and subsequent consolidation using spark plasma sintering. The plastic deformation behavior of BMG/crystalline composites was examined by uniaxial compression test at various temperatures in the supercooled liquid region (SLR) of the BMG alloy. The evolution of strain states during uniaxial compression was tackled by microstructure observations. Deformation temperature played an important role in the deformation behavior of BMG/crystalline composites, which was attributed to a strong temperature dependence of the flow stress of the BMG alloy in the SLR. BMG/crystalline composites deformed homogenously in the temperature range where the flow stress of the BMG alloy was close to that of crystalline nickel. In contrast, inhomogeneous deformation was observed in the temperature range where the flow stress of the BMG alloy largely differs from that of crystalline nickel.

• 대한전자공학회논문지SD
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• 제39권10호
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• pp.35-42
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• 2002

Modulation frequency dependences of the pyroelectric properties of PLT (P $b_{1-x}$ L $a_{x}$ $Ti_{1-x}$ 4/ $O_3$) thin films with La concentrations of 5, 10 and 15㏖% have been investigated by using the dynamic method. The PLT thin film with 10㏖% of the La concentration (PLT(10) thin film) shows the most excellent pyroelectric properties among the films. For PLT(10) thin film, the pyroelectric coefficient shows the maximum value of 6.6$\times$10$^{-9}$ C/$\textrm{cm}^2$ㆍK without frequency dependence. The figure of merits for the voltage responsivity and specific detectivity are 1.03$\times$10$^{-11}$ Cㆍcm/J and 1.46$\times$10$^{-9}$ Cㆍcm/J, respectively. Voltage responsivity corresponding to the pyroelectric voltage is almost constant at low modulation frequency and decreases in proportional to frequency at high modulation frequency. Voltage responsivity is 5.15 V/W at 8Hz. Noise equivalent power (NEP) and specific detectivity ( $D^{*}$) of the PLT(10) thin film are 9.93$\times$10$^{-8}$ W/H $z^{1}$2/ and 1.81$\times$10$^{6}$ cmH $z^{1}$2/W at the frequency of 100Hz, respectively. The results indicate that PLT(10) thin film is very suitable for pyroelectric IR sensors.s.s.

• 센서학회지
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• 제23권4호
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• pp.224-228
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• 2014

The electrocaloric effect of 9/65/35 PLZT thin film fabricated by the sol-gel method, which has not been studied yet, was investigated for its structural, electrical properties as well as temperature change property. The relaxor ferroelectric property of 9/65/35 PLZT thin film was confirmed by examining its dielectric and electrical properties. The relaxor property can cause a more pronounced electrocaloric effect (ECE) in a wider temperature range than normal ferroelectric film. To avoid errors caused by using an indirect measurement method, the leakage current generated by increasing temperatures was minimized by using the optimal maximum electric field ($350kVcm^{-1}$) in the thin film. The largest temperature change ${\delta}T$ (0.23 K) and the electrocaloric strength ${\xi}$ (0.68 mkcm/kV), calculated by equations were obtained. The maximum field change ${\delta}E$ ($191kVcm^{-1}$) was in the vicinity of the curie temperature ($200^{\circ}C$).

• Journal of Electrical Engineering and Technology
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• 제4권4호
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• pp.527-530
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• 2009

$(Ba_{0.57}Sr_{0.33}Ca_{0.10})TiO_3$(=BSCT) powders, prepared by the sol-gel method, were doped using $MnCO_3$ as the acceptor and $Dy_2O_3$ as the donor. This powder was mixed with an organic vehicle. BSCT thick films were fabricated by the screen-printing techniques on the alumina substrate. The structural and dielectric properties of BSCT thick films were investigated with variation of the $Dy_2O_3$ amount. As a result of the differential thermal analysis (DTA), the exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All the BSCT thick films showed the XRD patterns of a typical polycrystalline perovskite structure. The average grain size of BSCT thick films decreased with an increasing amount of $Dy_2O_3$. The relative dielectric constant and dielectric loss of the BSCT thick film doped $Dy_2O_3$ 0.1mol% were 4637.4 and 1.6% at 1kHz, respectively.

• 대한치과보철학회지
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• 제42권3호
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• pp.301-306
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• 2004

Statement of problem. Fibronectin mediates its biological effects by binding to integrins on cell membranes through a consensus site including the Arg-Gly-Asp (RGD) sequence within tenth type III module. Purpose. The purpose of our study was to investigate the adsorption affinity of human recombinant fibronectin peptide (hFNIII 9-10) to titanium and to investigate the effect of the surrounding ionic composition on the adsorption process. Material and methods. As for evaluating the affinity of hFNIII 9-10 to Ti, titanium disks were incubated in 40, 80 and $120{\mu}g/ml$ hFNIII 9-10 solution at $37^{\circ}C$ overnight, repectively. As for evaluating the effect of surrounding ionic concentration, hFNIII 9-10 was dissolved in distilled water, phosphate buffered saline and RPMI 1640. Optical density (O.D.) was measured in ELISA reader. Results. The results were as follows; 1. The adsorption of hFNIII 9-10 showed significantly highest mean optical density (O.D.) value in $80{\mu}g/ml$. 2. The difference of ionic composition in DW, PBS and RPMI did not influence the adsorption amount of hFNIII 9-10.