• Bulletin of the Korean Mathematical Society
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• v.53 no.3
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• pp.651-656
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• 2016

Let G be a finite group and nse(G) be the set of numbers of elements of G of the same order. In this paper, we prove that the simple group $Sz(2^{2m+1})$, where $2^{2m+1}-1$ is a prime number, is uniquely determined by $nse(Sz(2^{2m+1}))$ and ${\mid}Sz(2^{2m+1}){\mid}$.

• Journal of the Korean Chemical Society
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• v.57 no.3
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• pp.361-364
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• 2013

A modified synthetic approach to the synthesis of heterocyclic food mutagens, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PHIP) and 2-amino-1,6-dimethylimidazo[4,5-b]pyridine (DMIP) is reported. This route highlights an optimized palladium catalysed Buchwald cross-coupling of 2-halo-1-methyl-imidazo[4,5-b]pyridine with benzophenoneimine followed by acidic hydrolysis to yield compound 7. Using finely tailored conditions, Suzuki cross-coupling reactions with highly efficient catalytic systems were performed as the final step on 8 to introduce the aryl group and methyl group on the heterocyclic core.

• Proceedings of the Korean Society of Life Science Conference
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• 2002.03a
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• pp.92-92
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• 2002

• Proceedings of the Ginseng society Conference
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• 2003.12a
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• pp.19-19
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• 2003

• Kyungpook Mathematical Journal
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• v.49 no.1
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• pp.7-14
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• 2009

In this short note, we consider a family of linear representations of the braid group and the fundamental group of a punctured torus bundle over the circle. We construct an irreducible (special) unitary representation of the fundamental group of a closed 3-manifold obtained by the Dehn filling.

• Journal of applied mathematics & informatics
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• v.8 no.3
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• pp.889-897
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• 2001

Based on the prime graph of a finite simple group, its order is the product of its order components (see[4]). It is known that Suzuki-Ree groups [6], $PSL_2(q)$ [8] and $E_8(q)$ [7] are uniquely deternubed by their order components. In this paper we prove that the simple groups $A_p$ are also unipuely determined by their order components, where p and p-2 are primes.

• Journal of the Korean Chemical Society
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• v.66 no.6
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• pp.442-450
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• 2022

Diverse pyrrolo[3,2-d]pyrimidines that are expected to exhibit bioactivity were synthesized through O-arylation and Suzuki coupling reactions. Microwave-assisted O-arylation was successfully performed using a Cu metal catalyst, so that 4 position of pyrrolo[3,2-d]pyrimidine could be substituted with phenol group. In addition, 4-aryl substituted pyrrolo[3,2-d]pyrimidines were synthesized with good to excellent yields by microwave-assisted Suzuki coupling reaction using a Pd metal catalyst. By using microwaves as reaction conditions for diversification of derivatives, it was possible to dramatically overcome the disadvantages of traditional heat reactions of long reaction times and heat transfer efficiency problems. The result of this study can be used to be diversify pyrrolo[3,2-d]pyrimidine derivatives, which are expected to play an important role in the drug discovery research.

• Bulletin of the Korean Mathematical Society
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• v.50 no.3
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• pp.929-934
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• 2013

In this short note we discuss degrees of twisted Alexander polynomials and demonstrate an explicit example of a closed 3-manifold which is related to the degree formula due to Friedl, Kim and Kitayama.

• Kyungpook Mathematical Journal
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• v.56 no.3
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• pp.927-938
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• 2016

In this note, we study a monodromy map of a fibered 2-bridge knot. We show the monodromy map of a fibered 2-bridge knot as an element in the automorphism group of a free group.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1099-1100
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• 2006

The mechanical properties of ceramics materials can be tailored by designing their microstructures. We have reported that development of texture can be controlled by slip casting in a strong magnetic field followed by heating even for diamagnetic ceramics such as alumina. A strong magnetic field of 12T was applied to the suspension indcuding alumina powder to rotate each particle during slip casting. The sintering was conducted at the desired temperature in air without a magnetic field. C-axis of alumina was parallel to the magnetic field. Bending strength of textured alumina depended on the direction of oriented microstructure.