• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.425.1-425.1
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• 2014

Thermal transport in nanomaterials is not only scientifically interesting but also technological important for various future electronic, bio, and energy device applications. Among the various computation approaches to investigate lattice thermal transport phenomena in nanoscale, the atomistic nonequilibrium Green's function approach based on first-principles density functional theory calculations appeared as a promising method given the continued miniaturization of devices and the difficulty of developing classical force constants for novel nanoscale interfaces. Among the nanometerials, carbon atomic chains, namely the cumulene (all-doulble bonds, ${\cdots}C=C=C=C{\cdots}$) and polyyne (alternation of single and triple bonds, ${\cdots}C{\equiv}C-C{\equiv}C{\cdots}$) can be considered as the extream cases of interconnction materials for nanodevices. After the discovery and realization of carbon atomic chains, their electronic transport properties have been widely studied. For the thermal transport properties, however, there have been few literatures for this simple linear chain system. In this work, we first report on the development of a non-equilibrium Green's function theory-based computational tool for atomistic thermal transport calculations of nanojunctions. Using the developed tool, we investigated phonon dispersion and transmission properties of polyethylene (${\cdots}CH2-CH2-CH2-CH2{\cdots}$) and polyene (${\cdots}CH-CH-CH-CH{\cdots}$) structures as well as the cumulene and polyyne. The resulting phonon dispersion from polyethylene and polyene showed agreement with previous results. Compared to the cumulene, the gap was found near the ${\Gamma}$ point of the phonon dispersion of polyyne as the prediction of Peierls distortion, and this feature was reflected in the phonon transmission of polyyne. We also investigated the range of interatomic force interactions with increase in the size of the simulation system to check the convergence criteria. Compared to polyethylene and polyene, polyyne and cumulene showed spatially long-ranged force interactions. This is reflected on the differences in phonon transport caused by the delicate differences in electronic structure.

• 생약학회지
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• 제20권2호
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• pp.71-75
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• 1989

A new polyyne, panaxyne, was isolated from the Korean red ginseng. The structure was determined as tetradeca-13-ene-1, 3-diyne-6, 7-diol by comparison of spectral data. The $ED_{50}\;value$ of panaxyne as cytotoxicity against L1210 cell was $11.0\;{\mu}g/ml$. The lower cytotoxic activity of the substance relative to other ginseng polyynes is presumably due to lack of the essential structural part of hept-1-en-4, 6-diyne-3-ol.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.597-600
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• 2012

Polyynes were formed by laser ablation of a graphite target in deionized water ($H_2O$ and $D_2O$) and various organic solvents such as acetonitrile, n-hexane, and c-hexane and were identified by analyzing ultraviolet (UV) absorption and Raman spectra. We assigned the major UV absorption peaks that coincided with the electronic transitions corresponding to linear polyyne chains. The UV absorption peak intensities of a polyyne solution decreased as the holding temperature of the solution increased. Also, the absorption spectra of polyynes obtained by laser ablation of a graphite target at different volume fractions of $H_2O$ and $D_2O$ were examined.

• EDISON SW 활용 경진대회 논문집
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• 제2회(2013년)
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• pp.238-239
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• 2013

We studied the thermal and electron properties of covalent one-dimensional (1D) monatomic linear chains of carbon, particularly carbyne. We found the ${\alpha}$-carbyne (Polyyne, alternating single and triple C-C bond co-existing) is more stable than ${\beta}$-carbyne (Equally-spaced based on C-C double bond) energetically. As investigation of electron density of states (EDOS), polyyne and cumulene had different electronic characteristic, which corresponding metallic and semiconducting respectively. We also calculate the phonon dispersion, phonon density of states (PDOS) and phonon transmission of carbynes.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.3073-3074
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• 2009

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.625-628
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• 2012

We investigated the interaction between polyynes (linear carbon chains) and various metal nanoparticles (Ag, Au, and Cu) to provide insight into the optical properties of metal-polyynes systems prepared by different experimental techniques. Polyynes were produced by laser ablation in deionized water, metal nanoparticles solutions, and copper chloride solution. Metal nanoparticles complexes with polyynes were analyzed by Raman, surface-enhanced Raman scattering, and UV-vis spectroscopy.

• 약학회지
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• 제37권2호
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• pp.182-186
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• 1993

$\alpha$-Linolenic acid ethylester, $C_{19}$ spiroketalenolether polyyne, herniarin and steroid were isolated from the leaves of Artemisia selengensis (Compositae). The structures of the compounds were elucidated on the basis of spectroscopic evidence. Liver protective effects of these constituents were studied using galactosamine and CCI$_{4}$-induced cytotoxicity in primary cultured rat hepatocytes.

• Archives of Pharmacal Research
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• 제12권1호
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• pp.48-51
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• 1989

A new polyacetylene compound with cytotoxic activity against L1210 cells having diyne-ene and epoxy moiety, named panaxyne epoxide, was isolated from Panax ginseng C.A. Meyer. The chemical structure of the polyacetylene was determined to be tetradeca-13-ene-1,3-diyne-6,7-epoxide by UV, IR, $^1H-NMR,\;^{l3}$C-NMR and mass spectra.

• Applied Biological Chemistry
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• 제41권3호
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• pp.258-263
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• 1998

본 연구는 polyyne계 항생물질의 분자 구조와 활성관계를 체계적으로 살펴본 최초의 보고로서 친수성기와 tetrayne 부분을 갖고 있는 화합물이 강한 항균활성을 가질 것이라는 결과를 얻었다. 이와 같은 선행 연구결과를 바탕으로 보다 개선된 활성을 갖는 화합물을 합성하기 위하여 tetrayneol 부분 구조를 가지는 novel한 polyhydroxy 화합물인 당류 유도체를 합성하고 항균성과 구조와의 관계를 검토하였다.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2439-2442
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• 2012

In order to explore the effects of the solvent on the formation rate of polyynes, we investigated the absorption spectra of polyynes obtained by laser ablation of a graphite target in different solvents at 1064 nm. Polyynes so produced were confirmed by the Raman band around $2200cm^{-1}$ which corresponds to the carbon triple bonds. The production of polyynes by laser ablation turned out to be significantly affected by the ratio of the hydrogen and carbon atoms in the solvent molecule. No clear correlations were observed in the formation of polyynes for other properties of the solvent such bond dissociation energy, thermal conductivity, and total mass of hydrogen atoms per volume of solvent.