• 통합자연과학논문집
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• 제5권2호
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• pp.127-130
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• 2012

Polymerization of vinyl monomers is promoted by thianthrene cation radical as a part of our research concerning the reactions of various agents with readily isolable, yet highly reactive species and elucidate the biological activity. Thianthrene cation radical initiated the homopolymerization and copolymerization of styrene and ethyl vinyl ether. The polymerization yields decreased as the concentration of phenylacetylene or diphenylethylene increased. Such polymereization by cationic thianthrene radical could provide some clues for the reaction in living animals. Comments on possible polymerization mechanisms were suggested.

• 공업화학
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• 제2권3호
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• pp.279-288
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• 1991

몇 종류의 산화물을 혼합하여 그 장점들이 촉매의 특성으로 나타나도록 하는 복합산화물 촉매의 한 종류로서 스피넬 구조를 이루는 Mg- 및 Zn-페라이트를 촉매로 선정하여 Cr 치환에 따른 물성을 분석하고, 에틸벤젠의 탈수소 반응에 대하여 연구하였다. 촉매의 특성 분석에는 XRD, BET, TG/DTA, ESCA, TEM, TPD등의 분석법을 사용하였다. 페라이트 촉매에 대한 Cr 치환 효과를 검토하기 위하여 물성을 종합적으로 분석한 결과, 표면으로의 확산이 용이한 Cr 은 촉매의 표면적 증가와 구조의 안정성에 기여하는 구조적인 조촉매로서 작용하였다. 촉매의 반응성 실험에 있어서는 Cr의 치환에 따른 활성변화를 검토하였는데, $MgCr_xFe_{2-x}O_4$ 촉매에서 Cr 치환량이 증가할수록 산소의 유동성이 작아져 완전산화반응이 억제되고 스티렌으로의 선택도가 증가하였다.

• 대한화학회지
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• 제39권5호
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• pp.364-370
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• 1995

비산화-환원 금속인 Ga(III), In(III), TI(III)을 포함하는 금속 포르피린을 촉매제로 NaOCl을 산화제로 하여 올레핀의 촉매적 산화반응을 $CH_2Cl_2$에서 연구하였다. 포르피린은 $(p-CH_3O)TPP,\;(p-CH_3)TPP,\;TPP,\;(p-F)TPP,\;(p-Cl)TPP $그리고 $(F_20)TPP$를 사용하였다. 올레핀은 $(p-CH_3O)-,\;(p-CH_3)-,\;(p-H)-,\;(p-F)-,\;(p-Cl)-,\;(p-Br)styrene$ 그리고 cyclopentene, cyclohexene을 사용하였다. 올레핀 산화반응에서 기질의 전환율(%)은 금속 포르피린 및 기질의 치환기 효과와 중심 금속이온 성질에 따라 고찰하였다. TPP 치환기에 따른 전환율의 변화는 $p-CH_3O$ < $p-CH_3$ < H < p-F < p-Cl 순서로 증가하였다. 이러한 증가는 TPP의 $4{\sigma}$값의 증가 순서와 일치하였다. 기질의 치환기에 따른 전환율의 변화는 $p-CH_3O$ > $p-CH_3$ > H > p-Cl > p-Br 순서로 치환기의 ${\sigma}^+$값이 증가할수록 오히려 감소하였다. 올레핀의 산화 반응에서 In(III)-, Tl(III)-포르피린은 Ga(III)-포르피린에 비하여 높은 촉매 활성을 나타내었다.

• 대한화학회지
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• 제59권3호
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• pp.215-224
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• 2015

Unsymmetrical tetradentate Schiff base N-(2-hydroxy-5-methylacetophenone)-N'-(2-hydroxy acetophenone) ethylene diamine (H₂L) and its complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, IR, electronic spectra and thermogravimetric analyses. ¹H, ¹³C-NMR and FAB Mass spectra of ligand clearly indicate the presence of OH and azomethine groups. Elemental analyses of the complexes indicate that the metal to ligand ratio is 1:1 in all complexes. Infrared spectra of complexes indicate a dibasic quadridentate nature of the ligand and its coordination to metal ions through phenolic oxygen and azomethine nitrogen atoms. The thermal behavior of these complexes showed the loss of lattice water in the first step followed by decomposition of the ligand in subsequent steps. The thermal data have also been analyzed for the kinetic parameters by using Horowitz-Metzger method. The dependence of the electrical conductivity on the temperature has been studied over the temperature range 313-403 K and the complexes are found to show semiconducting behavior. XRD and SEM images of some representative complexes have been recorded. The antimicrobial activity of the ligand and its complexes has been screened against various microorganisms and all of them were found to be active against the test organisms. The Fe(III) and Ni(II) complex have been tested for the catalytic oxidation of styrene.

• 방사선산업학회지
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• 제9권2호
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• pp.57-62
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• 2015

In this study, we fabricated effect of storage conditions on graft of polypropylene (PP) non-woven fabric induced by electron beam. The electron beam irradiations on PP non-woven fabric were carried out over a range of irradiation doses from 25 to 100 kGy to make free radicals on fabric surface. The radical measurement was established by electron spin resonance (ESR) for confirming the changes of the alkyl radical and peroxy radical according to effect of storage time, storage temperature and atmosphere. It was observed that the free radicals were increased with irradiation dose and decreased with storage time due to the continuous oxidation. However, the radical extinction was significantly delayed due to reduced mobility of radicals at extremely low temperature. The degree of graft based on the analysis of ESR was investigated. The conditions of graft reaction were set at a temperature: $60^{\circ}C$, reaction time: 6 hours and styrene monomer concentration: 20 wt%.

• 실내환경 및 냄새 학회지
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• 제17권4호
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• pp.381-388
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• 2018

In this study, various conditions and phenomena that occur in the process of removing odorous VOCs by using electrolyzed oxidant were examined. The formation of hypochlorous acid, which is an oxidant produced by electrolysis, was investigated and the properties of the oxidizing agent used to decompose toluene, xylene, and cyclohexane were investigated. As a result, it was found that the production rate and the final concentration of the oxidizing agent increased with the current density. It was found that the degree of removal varies depending on the property of each pollutant. Interestingly, in the batch experiments in which the pH of the produced oxidant was controlled, it was found that the degree of elimination varied depending on the pH of the substance. These results suggest that the difference in the concentration and distribution of hypochlorous acid (HOCl) and hypochlorite ($OCl^-$) due to the pH change leads to the difference in oxidizing power on the oxidation characteristics of each substance. Styrene and terpineol showed better degradation characteristics than toluene and xylene in odorous VOC removal experiments by spraying electrolytic oxidant using a lab-scale continuous reactor. In conclusion, the removal of odorous VOCs by the electrolytic oxidant can have various applications in that it can oxidize pollutants of various spectra.

• 공업화학
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• 제29권3호
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• pp.330-335
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• 2018

서로 다른 중합 메카니즘(산화 커플링 중합 및 라디칼 중합)을 가지는 둘 이상의 단량체를 동시에 공-증발 기상 중합(SC-VPP)을 하여 유기-유기 전도성 복합 박막을 제조하는 새로운 접근법을 보고한다. 본 연구에서는 SC-VPP 공정을 통해 poly(3,4-ethylenedioxythiophene)(PEDOT)와 poly(styrene-co-maleic anhydride)(PSMA)로 구성된 PEDOT-PSMA 복합 박막을 제조하였다. 유기-유기 전도성 복합체 박막의 제조는 FT-IR 및 $1^H-NMR$ 분석을 통해 확인되었다. 전자주사현미경을 통한 표면 형태학 분석으로 PEDOT-PSMA 박막이 PEDOT 박막보다 좀 더 거친 표면을 보였다. 이것은 소수성 특성을 가지는 PEDOT과 친수성 특성기를 가지는 PSMA와의 좋지 않은 상용성 때문이라고 생각된다. 따라서 PEDOT-PSMA는 PEDOT보다 낮은 전기 전도도를 나타내었지만 약염기인 2-ethyl-4-methyl imidazole을 첨가하면 크게 개선되었다. PEDOT-PSMA의 접촉각은 PEDOT의 경우 $62^{\circ}$에 비해 약 $50^{\circ}$로 친수성이 증가하였고, 이는, PSMA가 가지는 카르보닐기에 의한 것이라 판단된다. 제안된 SC-VPP 기반 유기-유기 하이브리드 박막 제조 경로를 통하여 다양한 고분자 전도성 박막의 표면 특성(친수특성, 기계적 강도, 광학특성 및 표면 거칠기) 등을 제어할 수 있다고 판단한다.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.681-686
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• 2004

Ti-ZSM-5 prepared by secondary synthesis, from the reaction of H-ZSM-5 with vapor phase $TiCl_4$, was characterized with several physicochemical techniques including FT-IR and UV/VIS-DRS. It was found that zeolite structure, surface area and pore volume did not change, and the framework aluminum could not be replaced by titanium atom during the secondary synthesis of Ti-ZSM-5. The incorporation of titanium into the framework might be due to reaction of $TiCl_4$with the silanol groups associated with defects or surface sites. The formation of extra-framework titanium could not be avoided, unless the samples were further treated by water vapor at 550 $^{\circ}C$ or higher temperature. High temperature steam treatment of Ti-ZSM-5 prepared by chemical vapor deposition with $TiCl_4$was efficient to prevent the formation of non-framework titanium species. Ti-ZSM-5 zeolites prepared in this work contained only framework titanium species and exhibited improved catalytic property close to TS-1 prepared by hydrothermal synthesis.

• 자원리싸이클링
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• 제13권2호
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• pp.9-15
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• 2004

석유화학공정으로부터 폐기되는 폐산화철촉매를 이용하여 도금합성폐수중 크롬회수에 관한 연구를 회분식과 연속식으로 실시하였다. 도금합성제수 중 $CrO _{4}^{-2}$ 형태의 음이온으로 존재하는 6가 크롬은 폐산화철촉매의 등전점(pH 3.0)이하에서 폐촉매와 물리적 흡착을 한다. 한편, 6가 크롬은 pH 3.0 이상에서도 폐촉매의 수산화철과 산화환원반응에 의해 일부 환원되어 $Cr(OH)_3$로 침전한다. 컬럼을 이용한 크롬 연속회수실험에서 크롬합성폐수의 pH가 0.5∼2.0일 때 폐촉매의 크롬흡착량은 2.0∼2.3g/L이며, pH가 3.0에서는 1.5g/L이었다. 폐수 중 크롬농도가 50∼500mg/L로 높아질수록 폐촉매에 흡착한 크롬누적량은 1.29∼8.56g/L로 증가하지만, 유속이 30∼80 ml/mm으로 증가하여도 크롬 흡착누적량은 2.21∼2.49 mg/L로 거의 유사하였다.