• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.3035-3037
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• 2010

• 분석과학
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• 제26권6호
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• pp.353-356
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• 2013

A method on the determination of caffeine in beverage with acridiene orange-${\beta}$-cyclodextrin (CD) inclusion complex was developed. The conditions such as pH of the sample solution and concentration of acridine orange and ${\beta}$-CD were optimized to 12.0(${\pm}0.5$), $1.9{\times}10^{-6}M$ and $1.25{\times}10^{-3}M$, respectively. Under these optimum conditions, the calibration curve of caffeine was obtained over concentration range of $5{\times}10^{-5}{\sim}1.1{\times}10^{-3}M$. The detection limit was $1.0{\times}10^{-5}M$. The relative errors(%) in beverage samples were less than 5.0%.

• Environmental Analysis Health and Toxicology
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• 제12권3_4호
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• pp.75-84
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• 1997

Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

• Journal of Pharmaceutical Investigation
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• 제26권4호
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• pp.257-261
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• 1996

The seeds of Zizyphus Jujuba have been used as an antianxiety agent for the treatment of insomnia from the earliest times. Sanjoinine-A, isolated from the seeds of Zizyphus Jujuba, have been found to have a minor tranquilizer activity. However this drug is poorly soluble in water. In order to increase the dissolution rate of sanjoinine-A, solid dispersions with PVP-MC and inclusion complex with ${\beta}-cyclodextrin$ were prepared and evaluated. All of these systems increased the dissolution rate of sanjoinine A comparing with sanjoinine-A free base. From pH-rate profile of sanjoinine-A at $60^{\circ}C$, it was found that sanjoinine A was relatively stable in acidic solution, but unstable in basic solution.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제20권4호
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• pp.243-249
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• 2013

Let A be an algebra and D a derivation of A. Then D is called algebraic nil if for any $x{\in}A$ there is a positive integer n = n(x) such that $D^{n(x)}(P(x))=0$, for all $P{\in}\mathbb{C}[X]$ (by convention $D^{n(x)}({\alpha})=0$, for all ${\alpha}{\in}\mathbb{C}$). In this paper, we show that any algebraic nil derivation (possibly unbounded) on a commutative complex algebra A maps into N(A), where N(A) denotes the set of all nilpotent elements of A. As an application, we deduce that any nilpotent derivation on a commutative complex algebra A maps into N(A), Finally, we deduce two noncommutative versions of algebraic nil derivations inclusion range.

• Journal of applied mathematics & informatics
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• 제29권1_2호
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• pp.49-53
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• 2011

In this paper, we adopt a numerical method to establish the smallest set to contain all Ger$\v{s}$gorin discs of a given complex matrix and its some similar matrices. With the smallest set, a new estimation for all eigenvalues of the matrix is obtained.

• Journal of Pharmaceutical Investigation
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• 제16권2호
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• pp.55-67
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• 1986

Inclusion complexation of tiaprofenic acid (TPA) with cyclodextrins $({\alpha}-,\;{\beta}-,\;{\gamma}-CyDs)$ in aqueous solution and in solid phase was investigated by solubility method, measurement of partition coefficient, ultra-violet, circular dichroism, infrared spectroscopies, powder X-ray diffractometry and differential scanning calorimetry. Investigations were made to prepare inclusion complexes of TPA with ${\beta}-CyD$ in solid powdered form by coprecipitation, freeze-drying, spray-drying and co-pulverization methods. The coprecipitation, freeze-drying and spray-drying methods were successful in obtaining inclusion complexes. The results showed that the latter two methods might be originally superior to the former in obtaining powdered inclusion completes. Especially, it was shown by powder X-ray diffractometry that spray-dried ${\beta}-CyD$ alone, TPA-spray-dried ${\beta}-CyD$ physical mixture, and spray-dried $TPA-{\beta}-CyD$ complex were amorphous. The dissolution behaviours of $TPA-{\beta}-CyD$ systems prepared by above four methods were compared with those of TPA alone and $TPA-{\beta}-CyD$ physical mixture, and the rates of dissolution of TPA in pH 1.2 buffer were greatly enhanced by inclusion complexation and copulverization.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2002년도 제35회 학술심포지움 및 춘계학술대회
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• pp.68-68
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• 2002

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1397-1399
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• 2001

• 대한화학회지
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• 제53권4호
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• pp.399-406
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• 2009

금속콜로이드에 흡착된 4-biphenyl acetonitrile(BPAN)을 $\alpha$-cyclodextrin($\alpha$-CD)으로 포접시킴으로 써 흡착배향을 변화시킬 수 있는지 여부를 알아보기 위하여 형광분광법을 이용하여 연구를 수행하였다. Au와 Ag 콜로이드 표면에 BPAN이 직접 흡착되는지 확인하기 위하여 온도증가에 따른 형광의 소광을 관찰하였다. 흡착이 이루어진 BPAN은 금속콜로이드의 종류에 상관없이 $\alpha$-CD와 포접화합물을 형성함을 발견하였으며 Benesi-Hildebrand 도시로부터 Au와 Ag에 흡착된 BPAN과 $\alpha$-CD의 포접화합물에 대한 형성 상수가 각각 32 $M^{-1}$과 13 $M^{-1}$인 것을 알아냈다. Au와 Ag 두 금속콜로이드에 흡착된 분자의 유사한 거동으로부터 $\alpha$-CD를 이용하여 분자의 흡착배향을 변화시킬 수 있음을 알게 되었다.