• Analytical Science and Technology
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• v.13 no.6
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• pp.759-765
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• 2000

A study on the separation of Zr metal from $LiF-BeF_2-ZrF_4$ (67-27-6 mol%) molten salt was carried out using electrowinning. The decomposition potentials of the $LiF-BeF_2$ (72-28 mol%) and the $LiF-BeF_2-ZrF_4$ (67-27-6 mol%) molten salts were measured to be -1.55 and -1.35 volt, respectively. The Zr separation voltage from the salt were found to be in a range of -1.4 -1.5 volt. As increasing applied current, the deposition of molten salt on a cathode increases but the current efficiency decreases. In addition, the deposition and current efficiency decreases with increasing temperature.

• Korean Journal of Materials Research
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• v.1 no.4
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• pp.214-220
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• 1991

The effects of $SiO_2$ reactive ion etching (RIE) in $CHF_{3/}C_2F_6$ on the surface properties of the underlying Si substrate were studied by X-ray photoelectron spectroscopy(XPS) and secondary ion mass spectrometry(SIMS) techniques. Angle-resolved XPS analysis was carried out as non-destructive depth profile one for investigating the chemical bonding states of silicion, carbon, oxygen and fluorine. The residue layer consists of C-F polymer. O-F bond was found on the top of the polymer layer and Si-O, Si-C and Si-F bonds were detected between Si substrate and polymer film. A 60nm thick damaged layer of silicon surface mainly contains carbon and fluorine.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.312-317
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• 2009

Genome analysis of a model filamentous fungus, Aspergillus nidulans, revealed that there are six putative forkhead genes. Among them, fkhF (AN8949.2) showed A. nidulans-specific. fkhF gene is located in chromosome VII and composed of 2,337 bp coding region for 778 amino acid. Since little is known about the involvement of the forkhead proteins in the developmental process of the filamentous fungi, including A. nidulans, we generated a deletion mutant of fkhF gene and analyzed. Deletion of fkhF resulted in less-dense conidiophore formation in a solid culture. However, the sexual developmental process or cleistothecia formation was normal. Furthermore, fkhF deletion mutant produced conidiophores and conidia under the submerged culture, suggesting that the fkhF gene is involved in repression of inappropriated induction and maturation of asexual developmental process but not in sexual development.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.362-368
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• 1997

Five formae speciales of Fusarium oxysporum in Korea were examined using RFLP analysis to find the possibility for classification and analyze genetic variations. DNAs from F. oxysporum f. sp. lycopersici, cucumerinum, fragariae, garlic and sesami were used with three recombinant probes such as pFC46, pFC52 and pFC57. Distinct differences among five formae speciales of this fungus were detected in RFLP band patterns based on southern hybridization of genomic DNA using each recombinant clone, which was a repetitive copy probe. Strains belong to four formae speciales could be very stable in genetic variation except f. sp. sesami which has more variation than the others based on the RFLP analysis. They formed their own cluster which has high similarity within the same formae specialis resulted from the UPGMA analysis for genetic relationship analysis and each cluster represented its own formae specialis. The method using three recombinant DNA probes could be a good tool for classification of formae speciales in F. oxysporum.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.419-423
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• 1998

The internal defects in $(CaF_2)$ single crystal were characterized by the observation of optical microscopy, the element analysis and the transmittance analysis. In bubble and negative crystal which are composed to crystal plane of (100) and (111), the spread negative crystal in $(CaF_2)$ crystal gave an effect of low transmittance. The precipitates formed in bubble as internal cavities were analyzed by using WDX. Violet colored-crystal had higher a dislocation density than non-colored crystal, and the atomic ratio between Ca and F changed by poor F ion. In this result, we could determine indirectly that violet color was occurred by poor F ion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1023-1028
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• 2004

RF magnetron sputtering을 이용하여 증착한 투명전도성 ZnO 박막의 F 도핑량에 따른 전기, 구조, 광학적 특성에 대해 고찰하였다. 순수 ZnO와 ZnO : $ZnF_2$(1.3 wt%) 그리고 ZnO : $ZnF_2$(10 wt%) 3개의 타겟들을 2개씩 조합 각각의 rf 파워를 조절하여 co-sputtering 방법으로 $ZnF_2$ wt%를 변화시켜 박막내의 F 도핑량을 조절하였다. 증착된 박막들은 열처리에 따른 물성 변화를 분석하기 위해 $5{\times}10^{-7}$ torr 이하의 진공 분위기에서 $300^{\circ}C$에서 2 시간 동안 열처리하였다. XRD 분석 결과 제작된 모든 ZnO 박막은 (002) 우선 방위 특성을 보였고 F 도핑량 증가에 따라 (101), (110), (100) 방향의 약한 피크들이 나타났으며, 이러한 구조적 특성 변화는 이동도의 변화와 밀접한 관계가 있는 것으로 나타났다. Auger로 박막 내의 F 량을 분석한 결과 최대 5.9 at%의 F이 포함되어 있었으며, 열처리 후 캐리어 농도와 이동도는 증가하였고 최고 $37cm^2/Vs$의 이동도를 나타내었으며, 모든 박막들은 가시광 영역에서 81 % 이상의 투과도를 가졌다.

• Analytical Science and Technology
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• v.14 no.4
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• pp.1075-1081
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• 2001

Instrumental Neutron Activation Analysis as a representative method of nuclear analytical technique, has advantages of non-destructive, simultaneous multi-element analysis with the characteristics of absolute measurement method. Up to date, $k_0$-quantitative method which is accurate, convenient and user-friendly, has been generalized world-widely. In this study, it is intented to introduce the general concept of $k_0$-method and to measure $k_0$-parameters for the future implementation to our NAA system. For this objectives, the definition of relevant factors for the quantitative analysis and the equation for the experimental determination of parameters such as $Q_0$(${\alpha}$) and f were summarized. Furthermore, a foundation for the $k_0$-standardization method was prepared through the measurement of ${\alpha}$ and f-value which depend on the specific character of irradiation hole at NAA#1-hole of HANARO research reactor.

• Applied Biological Chemistry
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• v.43 no.3
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• pp.213-217
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• 2000

In order to investigate the removal effect of cadmium by polyphenol compound extracted from persimmon leaves(Diospyros kaki folium), animal test was done. Two fractions such as F-1 and F-2 from persimmon leaves were compared with their safety and function. The food intake of group F-1 and F-2 considerably decreased within 1% level. Cadmium addition influenced to rat growth(a tested animal), but food efficiency ratio(FER) wasn't shown any considerable difference in F-1 and F-2, as compared to the control. Cadmium content of liver, kidney and femur considerably decreased within 1% level in F-1 and F-2, compared to the control, cadmium content of liver decreased 25% in F-1, 28% in F-2 3150 decreased 22% md 25% in kidney. In femur, also decreased 53% in F-1 and 59% in F-2 respectively. The test of cadmium content in feces indicate that the content considerably increased within 1% level in both group F-1 and F-2, as compared to the control(42% in F-1, 54% in F-2). As shown the above results, have seen the removal effect of cadmium by polyphenol compound.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.52-57
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• 1999

The anionic complexes, [ln($C_6F_5)_4$]-, which are thermal and moisture sensitive, have been prepared by the reaction of In($C_6F_5)_3{\cdot}D(D=CH_3CN$, O($C_2H_5)_2$) with the system ($CH_3)_3SiC_6F_5$/CsF, $C_6F_5$MgBr or Cd($C_6F_5)_2$. The stable anionic indium(III) complexes are obtained through cation exchange with PNPCI ([PNP]= bis(triphenylphosphino)ammonium). The pure substance is obtained by column chromatography. These new anionic complexes are unambiguously identifed by NMR-spectroscopy, IR spectroscopy, molecular weight, DTA/TG and elemental analysis.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.35-35
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• 2018

터리풀속(Filipendula)은 장미과(Rosaceae), 장미아과(Rosoideae)에 속하는 다년생 초본이며, 북반구 온대지역의 산지지역에 서식하며 15-20여 종이 보고되어 있고, 이 중 10여종이 한국, 중국, 일본, 타이완 등의 동아시아 지역에 분포한다. 본 연구의 목적은 DNA 염기서열 자료를 이용하여 터리풀속(Filipendula)내 종들간의 계통관계를 규명하기 위하여 본 연구를 수행하였다. 이를 위해서 11종 29개체의 터리풀속(Filipendula)샘플과 외군인 산딸기나무속(Rubus)에 속하는 3종 5개체의 샘플을 이용하였다. 추가로 Genbank에서 3속 10종 18개의 염기서열을 다운받아 비교분석에 이용하였다. 계통연구를 위하여 엽록체에 존재하는 atpF-atpH, psbK-psbI, psbA-trnH, matK, rbcL, 5개 마커와 핵에 존재하는 ITS, 총 6개 마커의 염기서열을 생산하였다. 총 52개의 샘플에 대하여 엽록체유전체 5개 마커지역은 염기서열 길이가 3,485bp였고 핵 ITS지역은 631bp였으며, 이들을 합한 염기서열 길이는 4,116bp였다. 계통분석결과, 터리풀속(Filipendula)은 단계통군을 이루었다. F. occidentalis와 F. vulgaris가 기저분류군을 이루었고 이들은 각각의 아속에 해당한다. 그리고 나머지 종들은 모두 하나의 단계통군을 이루었다. 위의 결과들은 1961년 시미즈가 본 속을 Hypogyna아속, Filipendula아속, Ulmaria아속으로 나눈 분류시스템과 일치한다. 나아가 분자계통수에서 Ulmaria아속은 크게 4개의 subclade로 구분되었다. 먼저 subclade I에는 F. vestita, F. kiraishiensis, F. tsuguwoi, F. multijiuga, F. purpurea 등 5개 종으로 구성되었다. Subclade II는 F. ulmaria 한 종으로만 구성되었다. Subclade III에는 F. glaberrima, F. koreana, F. formosa, F.camtschatica 로 구성되었으며 subclade III에는 한국에 서식하는 3종이 포함되었다. Subclade IV에는 F. rubra, F. angustiloba, F. palmata, F. intermedia 4종으로 구성되었다. 이번연구에서는 Ulmaria아속내에 4개의 subclade가 존재함이 처음으로 확인되었다.