• Preventive Nutrition and Food Science
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• 제9권4호
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• pp.295-299
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• 2004

Alpha-tocopherol was thermally oxidized and degraded at high temperatures and the resulting products were chromatographically separated and identified by LC-MS. Alpha-tocopherol dissolved in glycerol was heated at 200^{\circ}C for 30 min. The thermal products were separated by hexane extraction and analyzed by HPLC using a reversed phase $\mu$-Bondapak $C_{18}-column$ with two kinds of elution solvents: a mixture of acetonitrile and methanol (3:2), and of acetonitrile, methanol, 2-propanol, chloroform and methylene chloride (3:2:5:0.5:0.5) in a gradient mode. The isolated thermal. products of alpha-tocopherol were more viscous than alpha-tocopherol, and dark brown in color. Major thermal degradation products of alpha-tocopherol were identified by LC-MS, and the structures of thermal products were proposed. Alpha-tocopherol and its thermal degradation products were degraded into fragments, mainly at the non-aromatic parts. The degradation products of alpha-tocopherol. were combined with oxidized product (tocopherylquinone) to make thermal. products through dimerization.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.103-106
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• 1999

Organic electroluminescent devices (OELDs) have received a great deal of attention due to their potential application as full-color displays. Europium complexes are known as excellent red light-emitting materials for OELDs since they show intense photoluminescence at around 612 nm with a narrow spectral bandwidth. In this study, a novel curopium complex, Eu(TTA)$_3$(TPPO) was synthcsizcd and its photoluminescent and electroluminescent characteristics were investigated with a device structure of ITO/TPD/Eu(TTA)3(TPPO)/A1q$_{3}$ Al, where sharp emission at the wavelength of 615 nm has been observed. Details on the electrical properties of these structures will be also discussed.

• 한국세라믹학회지
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• 제37권8호
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• pp.774-780
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• 2000

In order to improve luminescence prperty of phosphors, we have synthesized Zn2SiO4:Mn phosphors by a new chemical synthetic route, i.e., the homogeneous precipitation method. This method has featured that the formation of phosphoris completed at relatively low temperature of 105$0^{\circ}C$ and the particle morphology exhibits spherical shape to be well-dispersed and uniform size. At all the Mn concentration explored, phosphors prepared by this method have exhibited the improved emission intensities. In particular, the emission intensities of phosphors with Mn doping contents between 1 at% and 3.5 at% were higher about 40% than that of commercial phosphor. On the other hand, the decay time has been decreased from 23 ms to 11 ms with increasing Mn concentration. In addition, the phosphor composition containing 3 at% Mn has displayed the most saturated color.

• 한국세라믹학회지
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• 제49권6호
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• pp.493-497
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• 2012

We propose a new reliable, fast, and low cost identification method for similarly looking 0.3ct vivid yellow color of natural, HPHT treated, and synthesized diamonds. Conventional optical microscopy as well as low temperature PL(photoluminescence), FT-IR, UV-VIS-NIR, micro-Raman spectroscopy, and vibrating sample magnetometry(VSM) characterization were executed. We could not distinguish the natural diamonds from the treated or the synthesized stones with an optical microscopy, PL, FT-IR, and UV-VIS-NIR spectroscopy. However, we could identify the treated diamond with micro-Raman spectroscopy due to unique $1440cm^{-1}$ peak appearance. VSM revealed easily the synthesized diamond because of its ferromagnetic behavior. Our preliminary propose on employing the Micro-Raman spectroscopy and VSM might be suitable for identification of the similar looking vivid yellow colored diamonds.

• 한국의류학회지
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• 제26권8호
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• pp.1248-1253
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• 2002

Coocus laccae(Laccifer lacca Kerr), usually known as Lac, is a kind of cocoon which is parasitic on the tree around India and China. It contains the laconic acid of red colored dyes and has been used for cosmetic or natural dyeing prior to the introduction of New World cochineal. Nevertheless, the characterization of lac has not been studied, very little informed. The purpose of this study is to examine the effects of dyeing conditions fur Lac extract, such as pH of dye bath, concentration of Lac exact dyeing temperature and time, to find out the optimum conditions. The results were as follow. 1. The highest K/S values of the silk and wool was shown at PH 3 and PH 4. 2. K/S values of the silk came to nearly the adsorption equilibrium state at 40$^{\circ}C$ and the curve of wool showed a dramatic increase with the increase of temperature. 3. Dyed silk and wool fabrics showed good light fastness without using mordants.

• Mycobiology
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• 제44권4호
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• pp.330-334
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• 2016

In 2010, disease symptoms, including necrotic lesions on stems and leaves with circular yellow-brown or irregular brown color patches, were observed on cool-season turfgrass at golf courses (OHCC) and the Daegu University research farm in Gyeongbuk, Korea. We isolated the causal agent and identified it as Waitea circinata var. zeae by morphological characterization and molecular analysis. To the best of our knowledge, this is the first report of brown patch caused by W. circinata var. zeae on cool-season turfgrass in Korea.

• BMB Reports
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• 제39권5호
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• pp.502-510
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• 2006

2C-methyl-D-erythritol 2, 4-cyclodiphosphate synthase (MECPS, EC: 4.6.1.12) is the fifth enzyme of the non-mevalonate terpenoid pathway for isopentenyl diphosphate biosynthesis and is involved in the methylerythritol phosphate (MEP) pathway for ginkgolide biosynthesis. The full-length mecps cDNA sequence (designated as Gbmecps) was cloned and characterized for the first time from gymnosperm plant species, Ginkgo biloba, using RACE (rapid amplification of cDNA ends) technique. The full-length cDNA of Gbmecps was 874 bp containing a 720 bp open reading frame (ORF) encoding a peptide of 239 amino acids with a calculated molecular mass of 26.03 kDa and an isoelectric point of 8.83. Comparative and bioinformatic analyses revealed that GbMECPS showed extensive homology with MECPSs from other species and contained conserved residues owned by the MECPS protein family. Phylogenetic analysis indicated that GbMECPS was more ancient than other plant MECPSs. Tissue expression pattern analysis indicated that GbMECPS expressed the highest in roots, followed by in leaves, and the lowest in seeds. The color complementation assay indicated that GbMECPS could accelerate the accumulation of $\beta$-carotene. The cloning, characterization and functional analysis of GbMECPS will be helpful to understand more about the role of MECPS involved in the ginkgolides biosynthesis at the molecular level.

• Journal of Animal Science and Technology
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• 제50권5호
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• pp.633-640
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• 2008

소의 모색 발현에 결정적인 역할을 수행하며 Extension 좌위에 암호화되어 있는 melanocortin- 1 receptor(MC1R) 유전자형을 변형된 염기서열이 증폭되게 제작된 이중 mismatch primer 쌍을 이용하여 PCR-RFLP 방법으로 분석하였다. 증폭된 PCR 절편들은 MC1R 유전자에서 모색 표현형과 직접적으로 연관되어 있어 중요하게 다루어지고 있는 세 가지 대립인자들(ED, E+, e)로 MspI-과 AluI-RFLP에 의해 성공적으로 구분되었다. MC1R 유전자형의 분포를 조사한 결과 제주흑우는 세 가지 대립인자가 모두 출현하였고, 황－적모색의 한우와 호피문의 칡소에서는 흑모색우성 대립인자 ED가 출현하지 않았다. 반면, 우성흑모색으로 알려진 두 소 품종 Holstein과 Angus는 ED 대립인자의 빈도가 96% 이상으로 조사되었다. 한우×Holstein F1과 한우×Angus F1은 모두 ED/e의 유전자형을 나타내었고, 표현형은 전신 흑색으로 확인되었다. 본 연구에서 고안한 이중 mismatch primer 쌍을 이용한 MC1R 유전자 증폭 절편에 대한 MspI-과 AluI-RFLP 조합은 소의 품종 특성 규명과 품종 식별에서 매우 중요한 유전자 표지인자 중 하나인 MC1R 유전자의 세 가지 대립인자를 식별하는 데 유용한 실험기법이 될 것으로 사료된다.

• Applied Biological Chemistry
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• 제42권2호
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• pp.134-139
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• 1999

새로운 식용 적색색소자원을 개발하기 위하여 버찌의 anthocyanin색소를 ethanol 추출하여 광선, 온도, 유기산, 금속이온 및 pH에 의한 영향을 검토하였다. 본 색소는 광선에 안정하여 20일 까지도 69%의 색소잔존율을 나타내었고 광선 차단용 포장재를 사용 시 상당한 색소잔존효과를 나타내었다. 본 색소는 열에 대단히 안정하여 $115^{\circ}C$에서 30분까지 64%의 색소잔존율을 나타내었다. $25^{\circ}C$의 암소조건에서 첨가된 유기산에 의해서는 색소의 농색화효과가 높게 나타났으며, $25^{\circ}C$의 암소조건에서 첨가된 금속이온에 의해서는 $Na^+,\;K^+,\;Mg^{2+},\;Ca^{2+}$ 및 $Mn^{2+}$에 의해서는 20일까지 안정하였고, $Cu^{2+}$와 $Fe^{3+}$에 의해서는 심각한 안정성 저해를 나타냈으며, $Al^{3+}$에 의해서는 자색으로 전환되었다. pH가 낮을수록 색소의 농색화효과가 높았다. 이로 미루어 본 색소는 대단히 우수한 식용 적색색소자원임을 알 수 있었다.

• 한국수산과학회지
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• 제43권5호
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• pp.495-502
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• 2010

Pure lines were isolated from young gametophytic blades of pigmentation and morphological mutants in Porphyra tenera. Growth, blade-shape and photosynthetic pigment content of pure lines were compared with the wild type. Growth of blade length in the wild type (W, R-B), with round shape and brown color, was fastest at $5{\sim}10^{\circ}C$ and became slower as temperature increased. The blade-shape of the wild type changed from linear to round as temperature increased. The green type (R-G), with round shape and green color, showed slower growth, and the red type (R-R) 'with round shape and red color' showed faster growth than the wild type. The blade-shapes of the green and red types changed from elliptical or linear to round as temperature increased. The phycoerythrin (PE) / phycocyanin (PC) ratio of the green type was markedly lower and the PE/PC ratio of the red type was markedly higher than that of the wild type. The linear type (L-B), with liner shape and brown color, showed faster growth in blade length than the wild type at $10{\sim}20^{\circ}C$ and maintained its linear shape at $5{\sim}15^{\circ}C$. The content of photosynthetic pigments of the linear type was similar to that of the wild type. Each of the pure lines of pigmentation and morphological mutants that were isolated in the present study showed particular patterns in growth, blade-shape and photosynthetic pigment composition. Therefore, they are expected to be useful as new varieties by themselves and to be available for breeding and biotechnological studies.