• 제목/요약/키워드: O26

검색결과 3,451건 처리시간 0.026초

A Further Furostanol Glycoside From Smilax china

  • Kim, Sung-Whan;Chung, Kyu-Charn;Son, Kun-Ho;Kang, Sam-Sik
    • 생약학회지
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    • 제20권3호
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    • pp.145-146
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    • 1989
  • A furostanol glycoside, $mp\;190{\sim}198^{\circ}$, was isolated from the MeOH extract of Smilax china rhizomes. The structure was established as a mixture of $26-O-{\beta}-_D-glucopyranosyl-(25R)-22-methoxy-furost-5-en-3\beta,26-diol\;3-O-\alpha-_L-rhamnopyranosyl-(1\rightarrow2)-\beta-_D-glucopyranoside$ and its 22-hydroxy derivative on the basis of spectral data and chemical correlations.

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ABSOLUTE CONTINUITY OF THE MAGNETIC SCHRÖDINGER OPERATOR WITH PERIODIC POTENTIAL

  • Assel, Rachid
    • Korean Journal of Mathematics
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    • 제26권4호
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    • pp.601-614
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    • 2018
  • We consider the magnetic $Schr{\ddot{o}}dinger$ operator coupled with two different potentials. One of them is a harmonic oscillator and the other is a periodic potential. We give some periodic potential classes for which the operator has purely absolutely continuous spectrum. We also prove that for strong magnetic field or large coupling constant, there are open gaps in the spectrum and we give a lower bound on their number.

APPROXIMATE SOLUTIONS OF SCHRÖDINGER EQUATION WITH A QUARTIC POTENTIAL

  • Jung, Soon-Mo;Kim, Byungbae
    • Nonlinear Functional Analysis and Applications
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    • 제26권1호
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    • pp.157-164
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    • 2021
  • Recently we investigated a type of Hyers-Ulam stability of the Schrödinger equation with the symmetric parabolic wall potential that efficiently describes the quantum harmonic oscillations. In this paper we study a type of Hyers-Ulam stability of the Schrödinger equation when the potential barrier is a quartic wall in the solid crystal models.

분말형 MnOx와 V2O2/TiO2 촉매를 이용한 저온영역의 백필터 공정에서 질소산화물 제거 특성 (Characterization of NOx Reduction on Filter Bag Support System at Low Temperature using Powder Type MnOx and V2O2/TiO2 Catalysts)

  • 김병환;김정헌;강필선;유승관
    • 한국대기환경학회지
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    • 제26권1호
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    • pp.1-9
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    • 2010
  • In this study, the selective catalytic reduction of $NO_x$ with ammonia was carried out in a filter bag support reactor. The experiments were performed by powder type $MnO_x$ and $V_2O_5$/$TiO_2$ catalyst at low temperature between 130 and $250^{\circ}C$. Also, the effect of $SO_2$ and $H_2O$ on the NO conversion was investigated under our test conditions. The powder type catalysts were analyzed by X-ray photoelectron spectrum (XPS), X-ray diffraction(XRD), scanning electron microscopy (SEM) and thermal gravimetric analysis (TGA). It was observed that NO removal efficiency of the powder type $V_2O_5$/$TiO_2$ catalyst was 85% at low temperature($200^{\circ}C$) under presence of oxygen and that of $MnO_x$ was 50% at the same condition. The powder type $V_2O_5$/$TiO_2$ catalyst, in conclusion, was found to be available for SCR reaction in a filter bag support system.

UV/TiO2/H2O2를 이용한 축산폐수처리에 대한 연구 (A Study on the Swine Wastewater Treatment Using UV/TiO2/H2O2)

  • 김창균;정호진
    • 대한토목학회논문집
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    • 제26권3B호
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    • pp.321-327
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    • 2006
  • 본 연구는 축산폐수처리를 위해 광촉매의 적용가능성과 처리효율 및 범위를 실험하여 축산폐수처리에 대한 기초 자료로 제시하고자 한다. 축산폐수처리에 대한 광촉매양의 증가는 높은 처리효율을 나타냈으며 알카리 영역에서 보다 산성영역 특히 pH3에서 축산폐수처리 효과는 우수하게 나타났다. 또한 광촉매양의 증가에 따라 색도 보다는 $TCOD_{Mn}$의 제거가 빠르게 이루어 졌다. UV 또는 $TiO_2$를 단독으로 사용하여 폐수처리를 하였을 때 보다 $UV/TiO_2$를 함께 적용하였을 때가 처리효율은 우수하게 나타났으며 산화제로 과산화수소를 주입하였을 때 처리효율은 $UV/TiO_2$만을 적용하였을 때 보다 처리효율이 우수하게 나타났다. 본 실험에서의 과산화수소 적정 주입량은 200 mg/L이며 과산화수소 적정주입량이 보다 많이 주입되었을 때는 처리효율이 떨어지는 것으로 나타났다. 또한 과산화수소의 주입량은 실험 시 계속적으로 주입이 되어야 높은 처리효율을 얻을 수 있었다.

Na2O-MgO-P2O5 생체 유리의 탄성계수와 용해도 (Elastic Moduli and Dissolution Rates of Resorbable Na2O-MgO-P2O5 Bioglasses)

  • 한동빈
    • 한국세라믹학회지
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    • 제26권6호
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    • pp.850-854
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    • 1989
  • The elastic moduli and dissolution rates of 15 glasses with different mole ratios of sodium-magnasium-phosphate as potential non-toxic biomaterials were investigated. In this study, a 3-pint bending test, sonic resonance technique, and theoretical calculation were used to evaluate the modulus of elasticity. The dissolution rates at 37$^{\circ}C$(human body temperature) were determined by the measurement of mass changes in each sample for 24 weeks.

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