• 청정기술
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• 제25권1호
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• pp.56-62
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• 2019

입상 활성탄에 의한 murexide 흡착의 평형, 동역학 및 열역학 파라미터들에 대해 조사하였다. 실험은 흡착제의 양, 염료의 초기농도, 접촉시간과 온도를 변수로 하여 회분식 실험으로 진행하였다. 등온흡착평형관계는 293 ~ 313 K의 범위에서 Freundlich 식에 가장 잘 적용되었으며, Langmuir 식의 분리계수 $R_L$과 Freundlich 식의 분리계수 ${\beta}$로부터 입상 활성탄에 의한 murexide의 흡착조작이 적절한 처리방법이 될 수 있다는 것을 알았다. 또한 Dubinin- Radushkevich 식에서 얻은 흡착에너지(E)로부터 물리흡착공정임을 알 수 있었다. 흡착공정에 대한 동역학적 해석을 통해 반응속도식의 적용 결과는 유사이차반응식이 유사일차반응식보다 일치도가 높은 것으로 나타났다. Gibbs 자유에너지 변화($-0.1096{\sim}-10.5348kJ\;mol^{-1}$), 엔탈피변화($+151.29kJ\;mol^{-1}$)을 통해 흡착공정이 자발적 공정 및 흡열과정으로 진행되었음을 알 수 있었다. 또한 Gibbs 자유에너지 변화는 온도가 올라갈수록 감소하였기 때문에 입상 활성탄에 의한 murexide의 흡착반응은 온도가 올라갈수록 자발성이 높아졌다. 엔트로피 변화 ($512.4J\;mol^{-1}\;K^{-1}$)는 활성탄에 의한 murexide의 흡착반응이 일어나는 동안 고-액 계면에서 무질서도가 증가함을 나타냈다.

• 대한화학회지
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• 제5권1호
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• pp.76-79
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• 1961

The nickel has been separated and precipitated with dimethylglyoxime in the usual manner and dissolved the precipitates with hydrochloric acid. To the nickel solution, 0.2g of Murexide as an indicator and 5 ml of 20 percent tri-ethanol amine solution were added and titrated with a standard solution of EDTA. At the end point the color changes from yellow to deep purple. In this paper, the purpose is that conditions for titration and for separation from the interfering substances were investigated and a suitable procedure was found and applied on the determination of nickel in Korean nickel ores.

• 대한약리학회지
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• 제18권2호
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• pp.79-87
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• 1982

Higenamine(dl-demethylcoclaurine, dl-1-(4-hydroxybenzyl)-6,7-dihydroxy-1,2,3,4-tetrah-ydroisoquinoline hydrochloride), which has recently been isolated from Aconite root by Drs. Kosuge and Yokota, has known to be the main cardiotonic component of the Aconite root. The present study was undertaken to investigate the effects of Higenamine on the calcium binding and release and ATPase activity of fragmented cardiac sarcoplasmic reticulum under in vitro condition. The calcium binding and release of sarcoplasmic reticulum were measured by using the double-beam spectrophotometer and the calcium sensitive dye, murexide. In the presence of $10^{-4}{\sim}5{\times}10^{-3}M$ of Higenamine, the maximal calcium binding and the initial binding rate of porcine cardiac sarcoplasmic reticulum were inhibited dose dependently by up to 43%. However, the calcium release from cardiac sarcoplasmic reticulum, which was loaded with $Ca^{++}(50{\mu}M)$, was stimulated in dose dependent manner. When incubated in the medium of 20 mM Tris-maleate(pH 7.0), 100 mM KCl, 10 mM $MgCl_2,\;0.05mM\;CaCl_2\;and\;0.014{\sim}1\;mM\;Tris-ATP\;at\;30^{\circ}C$ in the presence of Higenamine $(10^{-4}{\sim}5{\times}10^{-3}M)$, both $Ca^{++}-and\;Mg^{++}-ATPase$ of sarcoplasmic reticulum were inhibited non-competitively by Higenamine and values of $K_i$ were 4.896 mM and 6.875 mM respectively. It is suggested from the above findings that the cardiotonic effects of Higenamine might be partially explained by the inhibition of calcium binding and the stimulation of calcium release from the sarcoplasimic reticulum which may increase the free intracellular calcium that is available in the contraction of the cardiac muscle fiber.