• Journal of the Korean Institute of Gas
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• v.26 no.6
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• pp.45-51
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• 2022

Technologies for collecting and treating pollutants from point sources are steadily being developed, but Non-point sources, it is difficult to develop emission treatment technologies and effective emission coefficients. However, since non-point sources make up about 60% of domestic emissions, and first of all, the method of calculating emissions should be reasonable, and the workplace should develop emission reduction technologies based on this. This study suggest the effectiveness and improvement of the emission coefficient currently used for the petrochemical industry with high emissions. The emission characteristics of non-point sources emission were confirmed by analyzing the LDAR (Leak Detection And Repair) data of OO company located in Yeosu, Jeollanam-do over the past five years. As a result, there was no difference in discharge characteristics according to fluid phase, but it was confirmed that there was a difference in the size of the device and the characteristics of each manufacturer. In addition, it was confirmed that the emission coefficient applied in the petrochemical industry was larger than that of the refining industry, and improvement measures were suggested. Through these studies, it is expected that emission coefficients specialized in the petrochemical industry can be applied and that the workplace itself will contribute to the development of technologies that can drastically reduce them.

• Journal of Korea Far Infrared Association
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• s.18
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• pp.18-27
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• 2003

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2589-2594
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• 2009

Aging phenomena of plasma polymer films were studied by using the surface analysis techniques of contact angle measurement, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (TOFSIMS), and atomic force microscopy (AFM). The polymer films were grown on an aluminum substrate by using a plasma polymerization method from a gas mixture of acetylene and helium, and the films were subsequently modified to have a hydrophilic surface by oxygen plasma treatment. Aging of the polymer films was examined by exposing the samples to water and air environments. The aging process increased the hydrophobicity of the surface, as revealed by an increase in the advancing contact angle of water. XPS analysis showed that the population of oxygen-containing polar groups increased due to the uptake of oxygen during the aging, whereas TOF-SIMS analysis revealed a decrease in the polar group population in the uppermost surface layer. The results suggest that the change in surface property from hydrophilic to hydrophobic nature results from the restructuring of polymer chains near the surface, rather than compositional change of the surface. Oxidative degradation may enhance the mobility and the restructuring process of polymer chains.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.166-168
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• 2007

고분자 전해질 연료전지는 다수의 단위 cell을 적층하여 stack을 형성하게 되며, 각 단위 cell 은 분리판과 MEA 사이에 gasket을 장착하게 된다. 이때 장착된 gasket은 분리판과 MEA사이의 일정한 gap을 유지하여 가스를 균일하게 분배되도록 할 뿐만 아니라, 가스 유출을 막는 sealing 재(材)로서의 역할을 한다. 따라서 고분자 전해질 연료전지의 성능확보를 위해서는 내구성 및 가스 기밀성이 우수한 gasket 개발이 무엇보다 중요하다. 본 연구에서는 이러한 gasket 물성을 만족시킬 수 있는 고분자 전해질 연료전지용 gasket을 개발하고자 하였으며, 이를 검증하기 위하여 가혹 조건에서 실험을 수행하였다. 그 결과 종래의 gasket 보다 열적, 화학적 및 가스기밀성 변에서 우수한 고분자 전해질 연료전지용 gasket을 얻을 수 있었다.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.407-410
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• 2011

An isolable activated ester, diethyl thiophosphoryl [(Z)-(2-aminothiazol-4-yl)-2-(methoxyimino)acetate (9a, DAMA) was prepared in high purity, which was at least stable for 7 d at $25^{\circ}C$ and 6 months at $5^{\circ}C$. Its reaction with 7-ACA (4) in the presence of tributylamine in i-PrOH provided cefotaxime (1) of high purity in good yield. Preparation of DAMA and its reaction with 7-ACA (4) to 1 was performed in one-pot manner, respectively with minimal unit operations of stirring and filtration.

• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.43-45
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• 2002

가스차단기의 성능은 노즐재질, 접점분리 속도 차단기의 치수 그리고 마크시간 등에 좌우되며 이러한 일련의 현상을 고찰하기 위한 유동현상을 모의하기 위해서는 기본적으로 두 접점의 상대운동 및 접점 사이에서 발생하는 아크 플라즈마(arc plasma)에 의한 전도, 대류, 복사현상 뿐만 아니라 아크전류에 의한 로랜츠힘(Lorentz's force), 용삭(ablation)에 의한 화학작용 등과 같은 매우 복잡한 물리적 현상을 고려해야 한다. 본 연구에서는 차단과정 중 대전류 영역에서의 아크특성과 마크에서 방출되는 강한 복사에너지에 의해 발생하는 PTFE 증기에 의한 영향을 고려하기 위해서 상용 CFD 프로그램인 PHOENICS에 아크 모델링과 고온에서의 $SF_6$-PTFE 혼합가스의 물성치 대입을 위한 보조 프로그램을 작성하여 해석을 수행하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.537-538
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• 2006

Split and recombine type reaction module was made by electrical discharge machining. The reaction module has special features to well mix the two reactants which have high flow ratio or high concentrations difference. It could be achieved by deviding one flow equally by two and inserting second flow in between. The mixing performance was measured by a parallel competing reaction with iodide-iodate system. The result shows that the developed three inlets micromixer has better mixing efficiency than comercialized Y type micromixer.

• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.305-308
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• 2008

We performed coupled-cluster calculations to determine the intermolecular interaction energy between two TiAu4 clusters. Our ab initio calculations predict that the binding energy is 2.89 eV, which is somewhat larger than the known binding energy of 2.0 eV for TiH4-TiH4. The intermolecular binding energy is relatively high, despite TiAu4 having all the attributes of a magic cluster. The favorable orbital interaction between occupied Au(6s) and unoccupied Ti(3d) orbitals leads to the strong dimeric interaction for TiAu4-TiAu4.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.794-796
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• 2009

We have studied the structures and stabilities of Au6 to explore the origin of the large discrepancy between relative energies obtained from the density functional theory (DFT) and ab initio correlated levels of theory. The MP2 methods significantly overestimate the stability of the non-planar isomer when the double-$\zeta$ polarization quality of basis sets, such as LANL2DZ+1f and CEP31G+1f, are used. However, we show that such preference for the non-planar structure at the MP2 level mainly originates from the large basis set superposition error.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1303-1310
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• 2008

Inhibitors of farnesyltransferase (FT), a key enzyme in the post-translational modifications of Ras proteins, have been extensively studied as novel anticancer agents in the preclinical stages, some of which are currently in clinical development. Previously, it has been reported that a novel FT inhibitor LB42907 inhibits Ras farnesylation in the nanomolar range in vitro. The aim of this study was to assess the antitumor efficacy of LB42907 in vitro and in vivo. Anchorage-independent growth of various human tumor cell lines was potently inhibited by treatment with LB42907, comparable to other FT inhibitors in clinical development. In the nude mouse, oral administration of LB42907 demonstrated potent antitumor activity in several human tumor xenograft models including bladder, lung and pancreas origin. Interestingly, significant tumor regression in EJ (bladder) and A549 (lung) xenografts was induced by LB42907 treatment. The effectiveness of LB42907 was also investigated in simultaneous combination with paclitaxel, vincristine, cisplatin or gemcitabine against NCI-H460, A549, and HCT116 cells in vitro using median-effect analysis. LB42907 markedly synergized with most anticancer drugs tested in this study in NCI-H460 cell. In contrast, LB42907 displayed antagonism or partial synergism with these drugs in A549 and HCT116 cells, depending on the class of combined drugs and/ or the level of cytotoxicity. Our results demonstrate that LB42907 is an effective antitumor agent in vitro and in vivo and combination of LB42907 with other chemotherapeutic drugs results in synergistic or antagonistic effects mainly in a cell line-dependent manner. Further preclinical study is warranted.