• The Korean Journal of Ceramics
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• v.5 no.4
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• pp.375-378
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• 1999

In tho XRD study of $56ZrF_4 \cdot34BaF_2 \cdot4AIF_3 \cdot(6-x)LaF_3 \cdotxLnF_3$ glassdLn=Ce, Nd, Gd, Th), halo pattern charactarktic fo an amorphous sample appeared. When the halo peak angle ($\theta_p$) was converted into a wavenumber with $Qp=4\pi sinG\pi/\lambda(\lambda$ is the wavolongth of the radialion used), it was found that the Qp values varied almost liuearly with the concentration 01 $LnF_3$. The emissiou spect1.a of $Ce^{3-}$-containing fluoride glasses nnder 273 nm excitation had a peak maximum at ea. 300 nm $(Ce^{3+}$ 5d-4f- transition). The maximal intensity of the fluorescence was observed when the $CeF_3$, content was extremely low (ca. 1 mol%j. DTA measurement revealed tbat these fluoride glasses had two crystallization temperatures. In $56ZrF_4. 34BaF_2. 4NF_3. (6-x)LaF_3 .xNdF_3$ glasses, the actmation energies of crystallization obtained from a Kssinger plot were 1.7 and 5.0 eV for the glass with x=2, and 1.9 and 5.6 eV for the glass with x=4.

• The Korean Journal of Mycology
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• v.18 no.3
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• pp.132-136
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• 1990

The vegetative nuclear divisions in hyphae and the chromosome of Fusarium were observed by use of HCI-Giemsa technique and light microscope. The chromosome of nuclear in F. moniliforme both 7150 and 7219 were eight. F. subglutinans 1082 was n=8 and n=7 in F. sub­glutinans 1083. F. nygamai 5668 was n=7 and n=5 in F. nygamai 7132. F. beomiforme 9758 and 9760 were n=7. F. coccidicola ATCC 24138 and F. acuminatum ATCC 16560 were n=6. From these results and other reports, the basic chromosomal number of these fungi might be speculated to be four.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.875-880
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• 2000

Reactive oxygen species are produced under diabetic conditions and possibly cause various forms of tissue damage in patients with diabetes mellitus. The aim of this study was to examine the effects of high glucose on the alloxan-induced beta cell injury. The insulinoma (RINm5F) cells were clutured either with high glucose (22.2 mM) or normoglucose (5.6 mM) in RPMI 1460 media for 3 days. The SOD activities were determined by spectrophotometric assay and nitroblue tetrazolium (NBT) stain. The effects of high glucose on the cytotoxicity of alloxan were also investigated in RINm5F cells and the cells viability were determined by 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) methods. Results showed that the CuZn-SOD activity was decreased but Mn-SOD activity was increased significantly in RINm5F cells cultured with high glucose (22.2 mM) media. The cytotoxicity of alloxan was increased by high glucose compared with normoglucose in RINm5F cells. Diethyl-dithiocarbarmate (DDC), as inhibitor of CuZn-SOC, also potentiate the alloxan-induced cytotoxocity in RINm5F cells. These results suggest that, in RINm5F cells, short term culture with high glucose media decreases Cu-Zn-SOD activity and the decreased activity of CuZn-SOD many one of the causative factors of beta-cell injury induced by high glucose.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.166-167
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• 2009

본 연구에서는 2,3,5,6-fluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ)를 이용한 유기 발광 소자의 전기적 특성에 대하여 연구하였다. F4-TCNQ 는 높은 전자 친화도를 가지고 있어서 전하 수송층이나 전하 주입층에 많이 사용되고 있다. 또한 TCNQ 유도체들은 물질의 전도도를 조절하는 용도로 많이 이용된다. TCNQ 유도체를 유기 발광 소자의 전하 수송층이나 전하 주입층에 이용할 경우, 소자의 구동 전압이나 효율과 같은 특성들이 향상된다고 알려져 있다. 우리는 소자 특성에 있어서 F4-TCNQ의 영향을 알아보기 위해서 ITO(170nm)/TPD(40nm)/$Alq_3$(60nm)/LiF(0.5nm)/Al(100nm)의 구조로 기본 소자를 제작하였다. 그리고 TPD층에 F4-TCNQ를 도핑하여 소자를 제작하였다. 도핑 농도는 5와 10%로 하였다. 또한 ITO와 TPD층 사이에 F4-TCNQ층을 1, 2, 그리고 5nm의 두께로 하여 소자를 제작하였다. F4-TCNQ를 5와 10% 도핑한 소자의 구동 전압은 도핑하지 않은 소자에 비해 감소하였다. 그리고, ITO와 유기물층 사이에 F4-TCNQ층을 삽입한 소자의 특성은 삽입하지 않은 소자에 비해 향상되었다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.4
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• pp.133-140
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• 2006

The growth characteristics and properties of large size $SrAlF_5$ single crystals are described and compared with those of $BaMgF_4$. Transmission spectra in the vacuum ultraviolet wavelength region indicate a high transparency of $SrAlF_5$ (about 90% without considering surface reflection loses) down to 150 nm, on contrast to the optical loses observed for $BaMgF_4$. The ferroelectric character of $SrAlF_5$ is evidenced by the reversal of the spontaneous polarization in a hysteresis loop. The higher potential of $SrAlF_5$ in comparison with $BaMgF_4$ for the realization of all-solid-state lasers in the ultraviolet wavelength region by the quasi-phase matching (QPM) technique is pointed out. $SrAlF_5$, besides a higher grade of transparency, shows a nonlinear effective coefficient similar to that of quartz and uniaxial nature, on contrast to the one order smaller nonlinear coefficient and biaxial character of $BaMgF_4$. The refractive index of $SrAlF_5$ from the ultraviolet to the near-infrared wavelength region is measured by the minimum deviation method. The Sellmeier and Cauchy coefficients are obtained from the fits to the curves of the ordinary and extraordinary refractive indices, and the grating period for the first order QPM is estimated as a function of the wavelength. The poling periodicity for 193 nm SHG from 386 nm is $4{\mu}m$.

• Honam Mathematical Journal
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• v.21 no.1
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• pp.75-95
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• 1999

Dimensions of irreducible $so_5(F)$-modules over an algebraically closed field F of characteristics p > 2 shall be obtained. It turns out that they should be coincident with $p^{m}$, where 2m is the dimension of coadjoint orbits of ${\chi}{\in}so_5(F)^*{\backslash}0$ as Premet asserted. But there is no subregular point for $g=sp_4(F)=so_5(F)$ over F.

• Proceedings of the Korean Nutrition Society Conference
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• 2000.11a
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• pp.56-56
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• 2000

본 연구는 철분결핍과 caffeine섭취가 흰쥐의 혈당과 과산화에 미치는 영향을 알아보기 위해서 수행되었다. 생후 2주된 48마리의 Sprague-Dawley 수컷 흰쥐를 철분과 caffeine의 첨가 수준에 따라 6군으로 나누어 4주간 사육하였다(C0F0 : caffeine 0%, Fe 5 ppm diet, C1F0 : caffeine 1%, Fe 5 ppm diet, C4F0 : caffeine 4%, Fe 5 ppm diet, C0F1 : caffeine 0%, Fe 50 ppm diet, C1F1 : caffeine 0%, Fe 50 ppm diet, C4F1 : caffeine 0%, Fe 50 ppm diet).(중략)

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1619-1625
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• 2012

The purpose of this study is to determine long-term storage conditions for winter kimchi. Kimchi was stored in a kimchi refrigerator for 6 months with or without fermentation. Four different temperature systems used were as follows: 5 days at $10^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F1), 1 day at $15^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F2), storage at $-1^{\circ}C$ (S1), or at $-2.5^{\circ}C$ (S2). Time periods required for F1, F2, S1, or S2 kimchi to reach pH 4.4 and acidity 0.6% were 2, 8, 12, and 22 weeks, respectively. Lactobacillus spp. growth on F1 and F2 kimchi was faster and greater than that on S1 and S2 kimchi, revealing a maximum concentration of 8~9 verses 6.8 log CFU/mL, respectively. However, Leuconostoc spp. were fully grown (8~9 log CFU/mL) on all four kimchi samples regardless of temperature, even at $-2.5^{\circ}C$, although the times required to reach maximum growth were different. Growth of Lactobacillus and Leuconostoc spp. both decreased after reaching maximum levels, except for F1 kimchi. Sensory evaluation results for 3 month storage showed that F1 kimchi was the best among kimchi samples in terms of appearance, acidic taste, carbonated taste, crispiness, and moldy smell. For 6 months of storage, F1 and S1 kimchi were the most highly evaluated among the kimchi samples. Sensory evaluation result for S1 kimchi stored at $-1^{\circ}C$ was comparable to that of F1 kimchi due to fully grown Leuconostoc spp. Acidities of F1 and S1 kimchi after 6 months of storage were 0.8 and 0.7%, respectively. Taken together, fermentation of kimchi at $10^{\circ}C$ for 5 days followed by storage at $-2.5^{\circ}C$ for 6 months was optimal for high quality kimchi. Sensory properties of winter kimchi were significantly influenced by the degree of fermentation.

• Animal Systematics, Evolution and Diversity
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• v.15 no.1
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• pp.1-9
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• 1999

As the 3rd series of the study on the family Lecithoceridae in Sri Lanka, 11 species of the genus Frisilia Walker, 1864, are recognized. Of these, 5 species, Frisilia thapsina, F, tricrosura, F. trizeugma, F. ancylosana, and F. neacantha are described as new to science, with illustrations fo their genitalia are given.

• Journal of the Chungcheong Mathematical Society
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• v.32 no.1
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• pp.127-138
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• 2019

In this paper, I investigate a stability of the following set-valued functional equation $$f(x+3y){\oplus}10f(x+y){\oplus}7f(-x){\oplus}5f(x-y)=5f(x+2y){\oplus}f(x){\oplus}f(2x){\oplus}f(x-2y)$$ in the sense of P. $G{\check{a}}vruta$.