• Title/Summary/Keyword: {\eta}

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A Study on Evaporation Characteristics of Ethanolamine for Removal COD and N (COD 및 N 제거를 위한 에탄올아민의 증발 특성 연구)

  • Jeong, Eun-Sun;Kim, Jong-Young;Ku, Hee-Kwon;Rhee, In-Hyoung;Park, Byung-Gi
    • Proceedings of the KAIS Fall Conference
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    • 2008.11a
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    • pp.423-426
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    • 2008
  • 에탄올아민(ETA: Ethanolamine)은 탄소, 질소, 산소로 이루어진 유기화합물로 각종 산업에서 널리 사용되는 물질이다. 이러한 ETA는 상온에서는 휘발성을 띠지만 산 염기의 평형상수가 9.4 이므로 그 이하에서는 양이온 형태로 존재한다. 또한 수중에 존재할 경우 COD 및 T-N을 유발하는 물질이므로 이를 제거해야 한다. 따라서 본 연구에서는 수중에 존재하는 ETA를 제거하기 위해 온도, pH, 내부압력에 따른 ETA 증발 특성을 조사하였다. ETA증발 초기에는 끓는점의 차이로 인하여 물이 먼저 증발하며 일정시간 경과 후 농축된 ETA가 급격히 증발하였다. 내부압력이 낮아짐에 따른 ETA 수용액의 끓는점은 낮아졌으며 내부압력이 160mmHg이하일 때 가열온도에 영향을 받지 않고 ETA는 전량 증발하였다. 대기압 상태에서 ETA의 증발량은 pH에 영향을 받지만 진공상태에서는 ETA의 부분압이 낮아져 그 영향력은 매우 적었다.

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On the Growth of Transcendental Meromorphic Solutions of Certain algebraic Difference Equations

  • Xinjun Yao;Yong Liu;Chaofeng Gao
    • Kyungpook Mathematical Journal
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    • v.64 no.1
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    • pp.185-196
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    • 2024
  • In this article, we investigate the growth of meromorphic solutions of $${\alpha}(z)(\frac{{\Delta}_c{\eta}}{{\eta}})^2\,+\,(b_2(z){\eta}^2(z)\;+\;b_1(z){\eta}(z)\;+\;b_0(z))\frac{{\Delta}_c{\eta}}{{\eta}} \atop =d_4(z){\eta}^4(z)\;+\;d_3(z){\eta}^3(z)\;+\;d_2(z){\eta}^2(z)\;+\;d_1(z){\eta}(z)\;+\;d_0(z),$$ where a(z), bi(z) for i = 0, 1, 2 and dj (z) for j = 0, ..., 4 are given functions, △cη = η(z + c) - η(z) with c ∈ ℂ\{0}. In particular, when the a(z), the bi(z) and the dj(z) are polynomials, and d4(z) ≡ 0, we shall show that if η(z) is a transcendental entire solution of finite order, and either deg a(z) ≠ deg d0(z) + 1, or, deg a(z) = deg d0(z) + 1 and ρ(η) ≠ ½, then ρ(η) ≥ 1.

Production of $\beta$-Mannanase and $\beta$-Mannosidase from Sporolactobacillus sp. M201. (Sporolactobacillus sp. M201 균주에 의한 $\beta$-Mannanase와 $\beta$-Mannosidase의 생산)

  • 박원식;김화영;최용진
    • Microbiology and Biotechnology Letters
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    • v.26 no.3
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    • pp.232-237
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    • 1998
  • A bacterial strain producing high levels of an extracellular ${eta}$-mannanase and intracellular ${eta}$-mannosidase and ${alpha}$-galactosidase was isolated from soil. The strain isolated was identified as a strain of Sporolactobacillus sp. and designated as Sporolactobacillus sp. M20l. Synthesis of ${eta}$-mannanase by Sporolactobacillus sp. M20l was induced by sucrose, maltose, or locust bean gum. The highest induction rate was obtained with 2% locust bean gum added to the culture medium as a sole carbon source. On the other hand, induction of ${eta}$-mannosidase was observed only with locust bean gum. The optimal media for the enzyme production were established as follows: for ${eta}$-mannanase; 2% locust bean gum, 0.5% peptone, 0.2% KH$_2$PO$_4$, 80 mg/l MgSO$_4$, and 8 mg/l ZnSO$_4$ (pH 6.0), and for ${eta}$-mannosidase; 2% locust bean gum, 0.5% yeast extract, 0.2% KH$_2$PO$_4$, 80 mg/l MgSO$_4$, and 8 mg/l ZnSO$_4$ (pH 5.0). The optimal culture temperatures for production of ${eta}$-mannanase and ${eta}$-mannosidase were found to be 37$^{\circ}C$ and 3$0^{\circ}C$, respectively. Under the optimal culture conditions, the production of ${eta}$-mannanase and ${eta}$-mannosidase reached the highest levels of 10.6 units/ml and 1.35 units/ml after 30 h and 24 h cultivation, respectively.

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Work Softening Behavior of Zn-15%Al alloy (Zn-15%Al 합금의 가공연화 거동)

  • Jun, Joong-Hwan;Seong, Ki-Duk;Kim, Jeong-Min;Kim, Ki-Tae;Jung, Woon-Jae
    • Journal of the Korean Society for Heat Treatment
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    • v.18 no.1
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    • pp.18-23
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    • 2005
  • Effect of cold rolling on microstructural changes has been investigated for a Zn-15%Al alloy to elucidate the reason for its work softening behavior. Fully annealed microstructure of the Zn-15%Al alloy is characterized by ${\eta}$ grains and (${\eta}+{\alpha}$) lamellar colonies, where ${\eta}$ and ${\alpha}$ are Zn-rich HCP and Al-rich FCC phases, respectively. The hardness decreases continuously with increasing cold rolling degree, exhibiting work softening behavior. It is revealed that during the cold rolling, (${\eta}+{\alpha}$) lamellar colonies gradually change into equiaxed ${\eta}$ and ${\alpha}$ grains due to dynamic recrystallization at room temperature, while pre-existing ${\eta}$ grains are only deformed without recrystallization. Furthermore, cold rolling causes the precipitation of dissolved Al solutes in ${\eta}$ grains. In view of these results, change of (${\eta}+{\alpha}$) phases from lamellar to equiaxed morphology, which results in structural softness and increase in equiaxed ${\eta}/{\alpha}$ grain boundaries with higher mobility, and deterioration of solution hardening by precipitation of Al solutes from ${\eta}$ grains, are thought to contribute to the work softening of Zn-15%Al alloy.

The Cytotoxic and Apoptotic Effect of Pseudomonas aeruginosa Exotoxin A on Human Leukemia K-562 Cells (인간 백혈병 세포에서 Psuedomonas aeruginosa exotoxin A에 대한 세포독성과 세포자멸사 효과)

  • Chang, Jeong-Hyun;Kwon, Heun-Young
    • Korean Journal of Clinical Laboratory Science
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    • v.39 no.2
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    • pp.68-75
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    • 2007
  • After reports on regression of cancer in humans and animals infected with microbial pathogens date back more than 100 years, much effort has been spent over the years in developing a wild type or attenuated bacterial and purified bacterial proteins for the treatment of cancer. Pseudomonas aeruginosa exotoxin A (ETA) is known to inhibit cell growth and trigger significant cell death in various cancer cells. Although ETA induces apoptosis of cancer cells, its exact mechanism of action is not known yet. Four different assays were performed in this study: morphological assessment of apoptotic cells, cell cytotoxity, annexin-V binding assay, and cell cycle analysis. The proliferation and survival of the K-562 cells treated with ETA were decreased in a dose dependent manner. In addition, the apoptotic body of K-562 cells was induced by ETA treatment in a dose dependent manner. The ETA-induced apoptosis was confirmed by annexin-V binding assay. Flow cytometric analysis was examined to ascertain whether ETA could arrest the cell cycle at the sub-G1 phase. Our results suggest that P. aeruginosa ETA inhibits cell growth and induces apoptosis in human leukemia K-562 cells.

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An Electro-palatographic Study of Palatalization in the Japanese Alveolar Nasal

  • Masaki Tsuzuki
    • MALSORI
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    • no.31_32
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    • pp.223-238
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    • 1996
  • It is widely hewn that the Japanese alveolar nasal [n] is affected by adjacent vowels in most positions, that is, the variants of the alveolar [n] occur conditionally. The Japanese [n] is palatalized under the influence of vowel [i] or palatal [j]. In the articulation of 'に', for instance, the tip and sides of the tongue make wide contact with the palate. It is interesting to know how palatalization occurs and varies during the production in different contexts. In my presentation the actual realization of the palatalized alveolar nasal in different contexts is examined and clarified by considering the Electro-palatographic data and examining the articulatory feeling and auditory impression. As a result, palatalized [${\eta}$] occurs either word-initially- or inter-vocalically. [${\eta}$] in [${\eta}$i] and 'いに'[$i{\eta}$] has great palatality. When conditioned by [j], the [${\eta}$] in 'にゃ'[${\eta}$ja], 'にょ'[${\eta}jo$] and 'にゅ'[${\eta}jw$] has full palatality. In each sound the average number of contacted electrodes of the Electro-palatograph at maximum tongue-palate contact is 63 or 100% of the total. To summarize the experimental data, articulatory feeling and auditory impression, it can be concluded that 'the [n] followed by or hemmed in [i], [j] is a palatalized nasal [${\eta}$].

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Development of Isolation Process of Barley Starch Using $\beta$-glucanase ($\beta$-Glucanase를 이용한 보리전분 분리공정의 개발)

  • 서호찬
    • Korean journal of food and cookery science
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    • v.15 no.3
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    • pp.238-243
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    • 1999
  • For the development of technique for isolation of naked barley starch from Youngsan variety, optimum conditions of the isolation process were investigated. The effect of blending was examined and the results showed that 29.7% starch yield was obtained by 6 times of blending. After the blending, the barley starch contained 3.2% protein, 0.7% fat, 0.4% fiber, 0.4% ash and 2.8% ${eta}$-glucan. The opitmum conditions of ${eta}$-glucanase treatment were studied and the results showed that the amount of ${eta}$-glucanase and barley flour-water ratio were 60,000 unit and 1/2, the optimum steeping temperature, pH were $45^{\circ}C$ and 6.5, respectively. The effect of alkali treatment which would be supposed to increase the yield and purity of the barley starch was also examined. 76.7% starch content was obtained by 2 hr of alkali treatment. After all the treatment of isolation process, the barley starch finally contained 0.2% protein and 0.1% ${eta}$-glucan.

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A NOTE ON THE θ3(0, τ)

  • Kim, Daeyeoul;Jeon, Hyeong-Gon
    • Korean Journal of Mathematics
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    • v.6 no.1
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    • pp.67-70
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    • 1998
  • Let ${\eta}(\tau)=q^{1/24}\prod_{n=1}^{\infty}(1-q^n)$, where $q=e^{2{\pi}i{\tau}}$ and ${\tau}{\in}\mathbb{C}$. Then the transformation $$g(\tau)={\rho}\frac{\{\eta(\frac{\tau+1}{2})\eta(\frac{\tau+2}{2})\}^{16}}{\eta(\tau)^{24}}({\bar{{\rho}}{\eta}}(\frac{\tau+1}{2})^8+{\eta}(\frac{\tau+2}{2})^8)^2$$ is holomorphic for Im ${\tau}$ > 0, and has the property $$g(\tau+1)=g(\tau),\;g(-\frac{1}{\tau})={\tau}^{12}g(\tau)$$. (Theorem)

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Application of ETA(Event Tree Analysis) to the Performance-Based Design of fire protection (성능위주설계를 위한 ETA 기법 활용 고찰)

  • Kim, H.B.;Lee, S.K.;Song, D.W.;Kim, K.S.;Kim, J.H.
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2011.11a
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    • pp.454-457
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    • 2011
  • 본 연구에서는 소방시설의 성능위주의설계를 수행하기 위하여 ETA(Event Tree Analysis) 기법을 적용하는 방안을 고찰하였다. ETA기법에서는 화재시나리오를 사건(Event)의 인과관계로 된 각 단계의 사건으로 구성한다. 본 연구에서는 ETA에서 구성된 시나리오에 따른 심각도를 화재시뮬레이션과 피난 시뮬레이션을 통한 수행으로 사망자수를 도출하는 방안을 적용하였고, 각 시나리오의 빈도(확률)은 FTA(Fault Tree Analysis) 기법을 적용하여 분기 확률을 도출하도록 하였다. ETA에서 도출한 사망자수와 빈도를 이용하여 F-N 커브를 작성하여 위험도를 평가하여 소방설계의 보완 및 대책을 수립하는 방안을 제시하였다.

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