• 한국지구과학회지
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• 제38권1호
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• pp.49-63
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• 2017

영남육괴 북동부에 위치하는 춘양화강암은 비알칼리계열 중 칼크-알칼리계열에 해당하는 I-type의 화강암류이며, 고알루미나질이다. 주성분원소 및 미량원소의 함량변화는 체계적인 연속성을 보이며, 일반적인 남한의 쥐라기 화강암류의 분화경향과 유사하다. 미량원소 중 유동성을 가지는 LILE (Sr, K, Rb, Ba)는 부화되어 있는 반면, 비유동성을 나타내는 HFSE 중 Ta, Nb, P, Ti의 함량은 상대적으로 결핍되어 있다. HREE에 대한 LREE의 강한 부화($(La/Lu)_{CN}=41.8-73.2$)와 Eu 부(-)이상[$(Eu/Eu^*)_{CN}=0.89-1.10$]은 남한에 분포하는 쥐라기 화강암류의 패턴과 매우 유사하다. 이러한 춘양화강암을 암체의 서쪽에 위치하며 영주저반의 대부분을 차지하는 부석심성암체와 비교하면 주성분원소 및 미량원소의 Harker 성분변화도에서 $SiO_2$ 함량에 따른 상관관계를 인지할 수 없어 두 암체는 성인적으로 무관한 별개의 암체로 사료된다. 춘양화강암은 지구조 판별도에서 화산호 환경에 도시되고 따라서 춘양화강암의 지화학적 특성을 종합해보면 쥐라기 고태평양판이 섭입하는 활동성 대륙주변부 환경에서 생성되었을 것으로 사료된다.

• 마이크로전자및패키징학회지
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• 제23권4호
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• pp.63-67
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• 2016

Divalent europium-activated $Ca_2PO_4Cl$ phosphor powders were prepared by a chemical synthetic method followed by heat treatment in reduced atmosphere, and the crystal structures, morphologies and photoluminescence properties of the powders were investigated by x-ray powder diffraction, scanning electron microscope and spectrometer. The effect of Ca/P mole ratio at the starting materials on the final products was evaluated. The optimized synthesis condition obtained in this study was Ca/P mole ratio of 2.0. The present phosphor materials had higher photoluminescence intensity and better color purity than the commercial blue phosphor powders, $(Ca,Ba,Sr)_{10}(PO_4)_6Cl_2:Eu^{2+}$. The result of excitation spectrum measurement indicated that the excitation efficiency of the synthesized powders was higher for the long-wavelength UV region than that of the commercial phosphor. It was thus concluded that the samples prepared in this study can be successfully applied for the light-emitting devices such as LED excited with long-wavelength UV light sources.

• The Plant Pathology Journal
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• 제24권3호
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• pp.279-282
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• 2008

This study describes a phytoplasmal disease occurring in Petunia leaves grown in the glasshouse of the National Horticultural Research Institute, Suwon, Korea. Abnormal growth like flattened stem with flower malformation or phyllody was observed from the plant. The DNA extracted from the diseased leaves was amplified using a universal primer pair of P1/P6 derived from the conserved 16S rRNA gene of Mollicutes giving the expected polymerase chain reaction(PCR) product of 1.5 kb. In the nested PCR assays, the expected DNA fragment of 1.1 kb was amplified with the specific primer pair R16F1/R16R1 that was designed on the basis of aster yellows(AY) phytoplasma 16S rDNA sequences. The 1.1 kb PCR products were cloned and nucleotide sequences were determined, and the sequences of the cloned 168 rRNA gene were deposited in the GenBank database under the accession no. of EU267779. Analysis of the homology percent of the 168 rDNA of PFS-K showed the closest relationship with Hydrangea phyllody phytoplasma(AY265215), Brassica napus phytoplasma(EU123466) and AY phytoplasma CHRY(AY180956). Phytoplasma isolated from the diseased Petunia was designated as Petunia flat stem phytoplasma Korean isolate(PFS-K) in this study. Flattened stem occurring in Petunia was confirmed as infection of AY group of phytoplasma by determination of 16S rRNA gene sequences of phytoplasma and microscopic observation of phytoplasma bodies. This is the first report on the phytoplasmal disease in Petunia in Korea.

• 생약학회지
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• 제9권4호
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• pp.177-180
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• 1978

In oriental medicine, Coptis japonica $M_{AKINO}$ (Ranunculaceae) has been known as bitter stomachics. This plant originally grows wild and has been cultivated in Japan but not in Korea. However, a few years ago, some workers have been trying to cultivate this plant in Korea and have made much progress. Therefore, this . study was made for the purpose of conforming possibility in cultivation of Coptis japonica $M_{AKINO}$ in Korea. The results were as follows: 1) Berberine contents of rhizomes are much more than of K.P.. Difference in contents between Eu Jeon Bu $(4.88{\pm}0.77%)$ and Bo Seong area $(3.62{\pm}0.50%)$ is significant (p<0.05). 2) Berberine contents of fibrous roots of Eu jeong Bu $(0.97{\pm}0.28%)$ area was similar to that of Gang Nam $(0.93{\pm}0.21%)$, Yang Pyung area $(0.91{\pm}0.14%)$ but only contents of Bo Seong area $(0.74{\pm}0.25%)$ is less than that of other area and it's difference is not significant. 3) It was considered that the cultivation of Coptis japonica $M_{AKINO}$ in Korea is possible considering the cultivation results and berberine contents, and also more moderate than south region.

• 한국재료학회지
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• 제16권10호
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• pp.624-628
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• 2006

In this study, divalent europium-activated $NaCaPO_4$ green phosphor powders were prepared by the chemical synthetic method followed by heat treatment in reduced atmosphere, and the crystal structures, morphologies and photoluminescent properties of the powders were investigated by x-ray powder diffraction, scanning electron microscope and spectrometer for the first time. The effects of Ca/P and Na/Ca mole ratios on the final products were also investigated. The influences of input amount change of europium as the activator on the light emission intensity were studied, and the resulting concentration quenching phenomenon was observed. The optimized synthesis conditions obtained in this study were Ca/P mole ratio 1.2, Na/Ca mole ratio 3.0 and 4 mole%Eu. The peak wavelength was 505 nm for all the samples. The result of excitation spectrum measurement indicated that the excitation efficiency was high for the long-wavelength UV region. It was thus concluded that the samples prepared in this study can be successfully applied for the light-emitting devices such as LED excited with long-wavelength UV light sources.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.784-787
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• 2008

Nanoscale $YVO_4:Eu^{3+}$ phosphor has been synthesized by a mild hydrothermal reaction at various experimental conditions. The particle and luminescent properties of nanophosphors were characterized with X-ray diffraction, electron microscopy and photoluminescence. It has been found that pH value play a key factor both controlling particle size and luminous efficiency.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.52-55
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• 2009

A red phosphor, $(Sr,Ca)_2P_2O_7:Eu^{2+},Mn^{2+}$, for UV-LED was synthesized under a reducing atmosphere, and its luminescent properties were investigated. The phosphor absorbs ultraviolet light at around 400 nm and efficiently emits red light at approximately 610 nm through an energy transfer from $Eu^{2+}$ to $Mn^{2+}$. Using the varied input current test for the phosphor-loaded LED lamps, it was found that the luminescent efficiency of the phosphor decreased with increasing light flux. This might be due to an increased probability of excited-state absorption and the consequent non-radiative relaxation in $Mn^{2+}$ ions in the condition of high photon influx.

• 대한수학회지
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• 제42권5호
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• pp.975-1002
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• 2005

On the setting of the upper half-space H of the Eu­clidean n-space, we show the boundedness of weighted Bergman projection for 1 < p < $\infty$ and nonorthogonal projections for 1 $\leq$ p < $\infty$ . Using these results, we show that Bergman norm is equiva­ lent to the normal derivative norms on weighted harmonic Bergman spaces. Finally, we find the dual of b$\_{$^{1}$.

• KSBB Journal
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• 제23권3호
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• pp.251-256
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• 2008

이 연구의 목적은 자연 천연한 청국장에서 분비되는 혈전용해효소를 생산하는 Bacillus Iicheniformis HK-12의 혈전용해활성과 특성을 조사하기 위하여 실시한 것이다. 먼저 균주 HK-12의 생리생화학적 특성에 대하여 조사하였다. BIOLOG GP2 MicroPlate system과 16S rRNA 염기서열 분석을 통하여 균주를 동정하였고, 그 결과 Bacillus licheniformis로 확인되었고, B. licheniformis HK-12로 명명하였으며, 이 균주는 GenBank에 [Eu288193]로 등재하였다. 16S rRNA 염기서열 분석에 근거하여, B. licheniformis HK-12의 계통수를 작성하였다. B. licheniformis HK-12의 배양기간동안 세균의 생장, 혈전용해활성, pH의 변화를 모니터링하였다. 36시간배양 후, 배양의 최대 혈전용해활성은 대조군으로서 플라스민과 비교하여 약 2.25배로 나타났다. 혈전용해활성과 관련하여, B. licheniformis HK-12의 생장에서 최적 pH와 온도는 각각 초기 pH 7.0과 40$^{\circ}C$로 나타났다.

• 분석과학
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• 제6권1호
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• pp.121-129
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• 1993

란탄족 원소 분석에서 란탄족 원소 상호간의 간섭영향에서 오는 방해영향을 제거하고 정확한 분석 결과를 얻기 위해 란탄족 원소들을 이온크로마토그래피로 분리하였다. 분리된 란탄족 원소들은 PAR(4-(2-pyridylazo)-resorcinol monosodium salt)과의 포스트컬럼 착색반응을 통하여 발색한 후, UV/VIS 흡광광도법으로 520nm의 파장에서 흡광도를 측정하여 란탄족 원소들을 분석하였다. 이때 용리액은 Pyromellitic acid였고 분리순서는 Sm, Eu, Gd, Y, Tb, Dy, Ho, Er, Tm, Yb, Lu였고, La, Ce, Pr, Nd는 pyromellitic acid로 분리되지 않으므로 옥산살을 사용하여 분리 분석하였다. Pyromellitic acid의 pH 2.99에서 중란탄족 원소들이 가장 잘 분리되었다.