• 대한화학회지
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• 제31권2호
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• pp.153-161
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• 1987

Benzenoid 탄화수소의 발암성은 분자의 위상학적 성질에 크게 의존하며, 특히 benzenoid탄화수소가 발암성을 가질려면 그 구조상에 "bay region"이라고 알려진 부분이 존재하여야 한다는 것이 널리 알려져 있다. 81가지 benzenoid 탄화수소에 대하여 발암성 "bay region"을 molecular connectivity index의 크기는 그들 화합물 중에 단일결합을 가지는 화합물을 제외하고는 아주 잘 일치함을 알 수 있었다.

• Journal of applied mathematics & informatics
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• 제31권5_6호
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• pp.595-608
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• 2013

Let G = (V, E) be a simple connected graph. The sets of vertices and edges of G are denoted by V = V (G) and E = E(G), respectively. In such a simple molecular graph, vertices represent atoms and edges represent bonds. The distance between the vertices $u$ and $v$ in V (G) of graph G is the number of edges in a shortest path connecting them, we denote by $d(u,v)$. In graph theory, we have many invariant polynomials for a graph G. In this paper, we focus on the Schultz polynomial, Modified Schultz polynomial, Hosoya polynomial and their topological indices of a molecular graph circumcoronene series of benzenoid $H_k$ and specially third member from this family. $H_3$ is a basic member from the circumcoronene series of benzenoid and its conclusions are base calculations for the Schultz polynomial and Hosoya polynomial of the circumcoronene series of benzenoid $H_k$ ($k{\geq}3$).

• Journal of applied mathematics & informatics
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• 제42권1호
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• pp.159-167
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• 2024

The Topological indices are known as Mathematical characterization of molecules. In this paper, we have studied line graph of subdivision and semi-total point graph of triangular benzenoid, polynomino chains of 8-cycles and graphene sheet through forgotten and first Zagreb indices.

• Archives of Pharmacal Research
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• 제27권9호
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• pp.912-914
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• 2004

Seven compounds were isolated from the stem of Acanthopanax senticosus by repeated col-umn chromatography. Their structures were elucidated as isovanillin (1), (-)-sesamin (2), iso-fraxidin (3), (＋)-syringaresinol (4), 5-hydroxymethylfurfural (5), eleutheroside B (6), and eleuth-eroside E (7) by spectral analysis. Among them, isovanillin (1) was isolated for the first time from the family Araliaceae.

• Bulletin of the Korean Chemical Society
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• 제11권2호
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• pp.105-108
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• 1990

A spectroelectrochemical study on the redox chemistry of polyaniline (PANI) was carried out by using indium-tin oxide (ITO) transparent electrode in aqueous acidic solutions. Three different PANI-derived species were observed depending on the potential. The most highly oxidized species having alternating benzenoid-quinoid structures degraded through hydrolysis reaction. The degradation products were confirmed to be p-benzoquinone (BQ) and p-diaminobenzene (PDAB) by spectrophotometry anld potentiostatic experiments. Finally, a degradation mechanism is deduced from the observed behaviour.

• Bulletin of the Korean Chemical Society
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• 제13권2호
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• pp.155-157
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• 1992

Extensive search over the energy surface of bicyclo[4.2.2]decapentaene with MMP2 molecular mechanics method and AM1 semiempirical MO method revealed only one, deep energy minimum structure, which corresponds to 1. The alternative structure 2 could not be identified as a stationary point. Although the deviation of benzenoid ring from planarity is large in the energy minimum structure (${\phi} = 26^{\circ}$(MMP2), $37^{circ}$ (AM1)), the bond lengths show no severe alternation.

• 대한전기학회논문지
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• 제44권7호
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• pp.889-894
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• 1995

The structural changes of the merocyanine monolayer LB (Langmuir Blodgett) films were investigated. These changes were compared with the typical changes of the molecular structures of merocyanine solutions. The structural changes of quinoid/benzenoid were attained by exposure to atmosphere gases (HCl gas, N $H_{3}$ gas). The photoisomerization was not observed for the monolayer LB film due to their state of $M_{trans}$. But we could obtain the cis/trans photoisomerization characteristics reversibly, after the films were changed to M $H^{+}$$_{trans}$ structure by exposure to HCl gas. We also found that the cis/trans photoisomerization of the LB monolayer films show the memory characteristics.s.

• 분석과학
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• 제8권4호
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• pp.631-636
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• 1995

Electrochemical properties of self-dopable poly(aniline N-butylsulfonate)s in various acidic medium were investigated by spectroelectrochemical techniques. Cyclic voltammetric study showed more than two reversible process of one electron transfer, the potential and peak intensity of which were dependent on the acid concentration and dopant ion. Spectroscopic study at different oxidation level indicated that the electrochromic switching of the poly(aniline N-alkylsulfonate)s film involves structural changes from benzenoid ring to quinoid ring. Spectrocyclic voltammetry together with impedance spectra of the PANBUS film in 0.1 M $LiClO_4$ solution of acetonitrile containing 0.46 M of perchloric acid showed two types of highly conductive states at the intermediate oxidation levels, which can be related to the metallic polaron states doped by two different process.

• Bulletin of the Korean Chemical Society
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• 제1권3호
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• pp.98-101
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• 1980

For the first time we have synthesized thiabenzene radical by the reaction of thiopyrylium cation with alkali metals. As might be expected for a free radical, ESR-spectrum of 2,4,6-triphenylthiabenzene radical shows the single signal with g-value of 2.0045. The proton signal of 2,4,6-triphenylthiabenzene radical in nmr spectrum shifts to the higher field than that of 2,4,6-triphenylthiopyrylium cation by ca. 0.5 ppm. From the UV-spectrum of thiabenzene radical the presence of 6${\pi}$ non-benzenoid aromatic system was observed as in the case of thiopyrylium cation. The reactivity of alkali metals with thiopyrylium cation increases in the order of decreasing ionization energy, Li

• 농업과학연구
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• 제29권2호
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• pp.91-97
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• 2002

식물병원균 Bipolaris sorokiniana 배양 추출물로부터 이탈리안 라이그라스 및 논피의 유근신장을 억제하는 활성물질을 분리 정제하여 각종 기기분석을 통하여 화학구조를 결정하였다. 이들 화합물들은 분자식이 $C_8H_8O_3$인 benzenoid 화합물인 3-methoxybenzoic acid와 3-hydroxy benzoic acid methyl ester로 숙주식물의 유근신장을 1000ppm에서 90% 이상 저해하였다. 이들 화합물은 식물체의 잎과 줄기에서 분리되어 항균활성 및 항류마티스 활성이 있음이 보고된바 있으나 B. sorokiniana로부터 분리되어 제초활성에 관하여 보고하기는 본 논문이 처음이다.