• Bulletin of the Korean Chemical Society
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• v.6 no.3
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• pp.173-175
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• 1985

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.457-459
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• 2015

Observations show that the accretion flows in low-luminosity active galactic nuclei (LLAGNs) probably have a two-component structure with an inner hot, optically thin, advection dominated accretion flow (ADAF) and an outer truncated cool, optically thick accretion disk. As shown by Taam et al. (2012), within the framework of the disk evaporation model, the truncation radius as a function of mass accretion rate is strongly affected by including the magnetic field. We define the parameter ${\beta}$ as $p_m=B^2/8{\pi}=(1-{\beta})p_{tot}$, (where $p_{tot}=p_{gas}+p_m$, $p_{gas}$ is gas pressure and $p_m$ is magnetic pressure) to describe the strength of the magnetic field in accretion flows. It is found that an increase of the magnetic field (decreasing the value of ${\beta}$) results in a smaller truncation radius for the accretion disk. We calculate the emergent spectrum of an inner ADAF + an outer truncated accretion disk around a supermassive black hole by considering the effects of the magnetic field on the truncation radius of the accretion disk. By comparing with observations, we found that a weaker magnetic field (corresponding to a bigger value of ${\beta}$) is required to match the observed correlation between $L_{2-10keV}/L_{Edd}$ and the bolometric correction $k_{2-10keV}$, which is consistent with the physics of the accretion flow with a low mass accretion rate around a black hole.

• YAKHAK HOEJI
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• v.41 no.6
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• pp.837-839
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• 1997

We have synthesized and evaluated (1S, 2R)-1-0-(ethoxycarbonyl)methyl-2,3-0-isopropylidene-1-phenyl-1,2,3-trihydroxypropane(5a) as a novel chiral auxiliary for opt ically active alpha-hydroxyesters.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.600-601
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• 2005

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.747-750
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• 2004

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1695-1698
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• 2003

• KSBB Journal
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• v.15 no.5
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• pp.415-422
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• 2000

Enzymatic resolution is becoming increasingly important in the production of optically active pharmaceutical drugs and is now challenging the traditional synthetic methods for production of a variety of chiral intermediates and products. This article reviews the recent advances in chirotechnology using enzymes as a catalyst to resolve chiral compounds. The review focuses on the recent trends in chirotechnology and the application of enzymes to the production of industrially valuable pharmaceutical drugs.

• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.859-863
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• 1995

The prostaglandin analogue 12-epi-PGF2α (2) has been synthesized from optically active cis-4-t-butyldimethylsilyloxy-2-cyclopenten-1-ol (4b) in 4 steps in an overall yield of 21%. An extremely efficient Pd(Ⅱ)-mediated, three-component coupling reaction is employed to obtain the key intermediate 9.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1261-1263
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• 2001

• Bulletin of the Korean Chemical Society
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• v.7 no.4
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• pp.308-311
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• 1986

(+)-(5S,6R)-Erythro-6-acetoxy-5-hexadecanolide, an optically active form of them ajor component of an oviposition attractant pheromone of a mosquito Culex pipiens fatigans, was synthesized enantiospecifically from (-)-2-deoxy-D-ribose.