• 공업화학
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• 제7권1호
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• pp.203-213
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• 1996

평형 추출장치를 사용하여 유기산의 물리추출과 반응추출에서 추출도에 미치는 추출제의 종류와 농도, 용매의 영향을 조사하였다. 사용된 유기산은 아크릴산과 메타크릴산이었고, 추출제로는 n-octylamine(OA)과 di-n-octylamine(DOA), tri-n-octylamine(TOA)및 tri-octylmetyl ammonium chloride(TOMAC ; Aliquat 336)을 사용하였다. 실험결과 반응추출에서 추출도는 물리추출의 경우보다 2~9배 정도 증가 되었으며, 유기산의 추출도에 미치는 추출제의 영향은 OA, TOMAC, DOA 및 TOA의 순서로 추출도가 증가하였으며, 또한 추출제의 농도가 증가할수록 추출도가 증가하였다. 용매의 영향은 종래의 용매의 유전상수보다는 용해도인자에 의한 용매선택 방법이 신뢰성이 있었고, 용질과 용매의 용해도인자의 차이가 작을수록 추출도가 증가하여 케로진, 크실렌, 클로로포롬, MIBK 및 n-BAc의 순서로 좋아졌다.

• 한국광물학회지
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• 제20권3호
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• pp.155-163
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• 2007

국내의 실리카 광물인 규질이암으로부터 실리콘알콕사이드와 같은 실리콘 유기화합물을 합성하였다. 이 실험에서는 알카리금속염 촉매 존재 하에서 트리에탄올아민과 규질이암의 반응에 의해 트리에탄올아민의 치환체인 트리스실라트라닐옥시에틸아민의 합성이 관찰되었다. 이 트리스실라트 라닐옥시에틸아민은 산성촉매인 발연황산의 존재 하에서 메탄올과의 반응으로 메톡시실란을 얻을수가 있었으며, 이 메톡시실란과 메탄올과의반응으로 테트라메톡시실란이 합성되었다. 반응의 중간 생성물 및 최종 산물은 FT-IR, XRD, SEM, 1H and 13C NMR 및 가스크로마토그래피에 의해 확인할 수 있었다.

• 약학회지
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• 제55권3호
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• pp.251-259
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• 2011

Cigarette smoke condensate (CSC) is known to be carcinogenic compound. CSC contains many organic compounds such as polycyclic aromatic hydrocarbons (PAHs), and heterocyclic amine compounds (HCAs). Reactive oxygen species (ROS) are also generated and induce oxidative DNA damage during the metabolism of CSC. The rat microsome mediated and DNA repair enzyme treated comet assays together with conventional comet assay were performed to evaluate the mechanisms of CSC genotoxicity. The organic extract of CSC induced oxidative and microsome mediated DNA damage. Vitamin C as a model antioxidant reduced DNA damage in endonuclease III treated comet assay. One of flavonoid, galangin as a CYP1A1 inhibitor, reduced DNA damage in the presence of S-9 mixture. The ethanol extracts of the mixed vegetables (BV) or the mixed fruits (BF) showed potent inhibitory effects against CSC induced DNA damage with oxidative DNA lesions and in the prescence of S-9 mixture. These results indicate that BV and BF could prevent CSC-induced cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P450 in mammalian cells.

• Macromolecular Research
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• 제12권3호
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• pp.263-268
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• 2004

We have synthesized a water-soluble polyimide precursor, poly(amic acid) amine salt (PAD), from pyromellitic dianhydride (PMDA), 4,4'-oxydianiline, and N,N -dimethylethanolamine (DMEA) and have investigated in detail its properties with respect to the degree of salt formation (D$\_$sf/). The maximum value of D$\_$sf/ we obtained upon precipitation of the precursor solution into acetone was 79%. We synthesized a PAD having a D$\_$sf/ of 100% (PAD100) by the solid state drying of an organic solution. The precursors showed different solubility depending on the D$\_$sf/ to make up to 4 wt% solutions in water containing a small amount of DMEA. PAD100 is completely soluble in pure water. We investigated the imidization behavior of PAD in aqueous solution using various spectroscopic methods, which revealed that PAD 100 has faster imidization kinetics relative to that of the poly(amic acid)-type precursors. The resulting polyimide films prepared from an aqueous precursor solution possess almost similar physical and thermal properties as those prepared from N-methyl-2-pyrrolidone(NMP) solution. Therefore, we have demonstrated that PAD can be used as a water-based precursor of polyimide; this procedure avoids the use of toxic organic solvents, such as NMP.

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.416-421
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• 1995

The approximate rates and stoichiometry of the reaction of excess lithium gallium hydride with selected organic compounds containing representative functional groups were examined under the standard conditions (diethyl ether, 0 $^{\circ}C)$ in order to compare its reducing characteristics with lithium aluminum hydride and lithium borohydride previously reported, and enlarge the scope of its applicability as a reducing agent. Alcohols, phenol, and amines evolve hydrogen rapidly and quantitatively. However lithium gallium hydride reacts with only one active hydrogen of primary amine. Aldehydes and ketones of diverse structure are rapidly reduced to the corresponding alcohols. Conjugated aldehyde and ketone such as cinnamaldehyde and methyl vinyl ketone are rapidly reduced to the corresponding saturated alcohols. p-Benzoquinone is mainly reduces to hydroquinone. Caproic acid and benzoic acid liberate hydrogen rapidly and quantitatively, but reduction proceeds slowly. The acid chlorides and esters tested are all rapidly reduced to the corresponding alcohols. Alkyl halides and epoxides are reduced rapidly with an uptake of 1 equiv of hydride. Styrene oxide is reduced to give 1-phenylethanol quantitatively. Primary amides are reduced slowly. Benzonitrile consumes 2.0 equiv of hydride rapidly, whereas capronitrile is reduced slowly. Nitro compounds consumed 2.9 equiv of hydride, of which 1.9 equiv is for reduction, whereas azobenzene, and azoxybenzene are inert toward this reagent. Cyclohexanone oxime is reduced consuming 2.0 equiv of hydride for reduction at a moderate rate. Pyridine is inert toward this reagent. Disulfides and sulfoxides are reduced slowly, whereas sulfide, sulfone, and sulfonate are inert under these reaction conditions. Sulfonic acid evolves 1 equiv of hydrogen instantly, but reduction is not proceeded.

• 청정기술
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• 제27권2호
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• pp.115-123
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• 2021

본 연구는 무기 실리카 껍질(shell)과 유기 고분자 코어(core)로 구성된 매우 균일한 유-무기 복합체 입자 제조의 방법에 관한 것이다. 먼저, 미세유체 기술을 이용하여 균일한 크기를 지니는 유기 고분자 코어 입자를 제조하였다. 코어 입자의 제조 과정에서 코어 입자의 제조 과정에서 광 경화성 유기 물질이 포함된 분산상과 연속상의 유속을 독립적으로 제어함으로써 균일한 액적을 형성하였다. 액적이 형성됨과 동시에, 미세유체 채널의 말단에서 자외선 조사에 의해 액적이 광중합 되어 코어 입자로 형성된다. 더불어, 폴리알릴아민 하이드로클로라이드(polyallylamine hydrochloride, PAH)와 인산 이온(phosphate ion)으로 구성된 나노 복합체는 최적화된 pH 조건에서 수소결합과 정전기적 인력 같은 강력한 상호작용을 통해 코어 입자에 코팅된다. 폴리아민 나노 복합체에 존재하는 PAH 주쇄의 아민 그룹들은 규산(silicic acid)의 축합(condensation) 반응을 촉매하여, 코어 입자 표면의 실리카 나노입자 성장을 시킬 수 있었다. 따라서, 본 방법을 통해 유기 코어에 무기 실리카 나노입자로 코팅된 유-무기 복합체 입자를 제조할 수 있었다. 최종적으로, 본 연구에서 제시한 방법은 보다 온화하며 환경친화적인 조건 하에서 단시간 내에 유-무기 복합체 입자를 합성할 수 있으며, 다양한 모양과 크기를 갖는 코어 입자에 적용되어 넓게 활용될 수 있다.

• 대한화학회지
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• 제28권2호
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• pp.130-134
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• 1984

반양성자성 용매인 아세토니트릴 중에서 benzeneazoresorcinol (BAR)의 폴라로그래프법적 거동을 직류 폴라로그래프법과 정전위전기량법으로 조사하였다. $1.0{\times} 10^{-2}$몰농도의 과염소산 테트라에틸암모늄의 아세토니트릴 용액 중에서 BAR은 1전자 4단계의 환원과정을 거쳐 아민 화합물로 환원되었다. 각 환원파는 비교적 확산 지배적이었고, 가역성은 나쁜 편이었다

• 환경위생공학
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• 제14권3호
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• pp.10-21
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• 1999

The purpose of study were to research the characteristics of water variation adding humic acids to distilled water after ozonation. Upon investigating pH variation with contact time after providing distilled water+air, distilled water+ozone and distilled water-humic acid-air in reactor, it reduced after 60 minute in inletting air and in spite of short contact time did suddenly in inletting ozone. TOC and UV-254 continued to increase with contact time of ozone and humic acids. $NH^{4+}-N$ did slowly increase or decrease after constant contact time of ozone, because $NH^{4+}-N$ was converted into $No^3-N$ by ozone. T-N did suddenly increase after 90minute, but T-P did rarely fluctuate for total experiment. Total 30 species of organic matter were detected by GS/MSD, but 14 species did really tend to increase except for matter identified in distilled water and blank test. Humic acids generated $aliphatic{\cdot}aromatic$ hydrocarbon, alcohol and amine etc., and did various matters without inflow course of contaminants.

• BMB Reports
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• 제36권3호
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• pp.251-257
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• 2003

Agmatine, an amine and organic cation, reduced $H_2O_2$ that was generated by hyperglycemia, and transcription factors such as NF-${\kappa}B$ and AP-1 activity in the mesangial cells that were exposed to high glucose. However, spermine which shares a strong nucleophilic structure with agmatine decreased the $H_2O_2$ levels and AP-1, but not the NF-${\kappa}B$ activity. Possible roles for agmatine and spermine in decreasing fibronectin are discussed, and the signaling pathway for agmatine-reduced fibronectin accumulation is presented.

• 한국염색가공학회지
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• 제1권1호
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• pp.26-34
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• 1989

The selective chemical degradation or etching of PET based on an organic amine attack on the ester group. The techniques involves the chemical removal of loss ordered amorphous regions or crystalline regions, which are essentially unaffected by the degradative etchant. Thus, most of previous studies have limited to consideration which has been given to structural changes taking place. Therefore, this study was carried out to investigate surface characterization, dyeing properties of PET film hydrazinolyzed with hydrazine hydrate in methanol. PET film was treated with 30% hydrazine hydrate in methanol at $30^\circ{C}$ for various time intervals. The total surface tension of treated PET increased, the dispersion force decreased and the hydrogen bonding force increased. The equilibrium dye adsorption, dyeing rate and apparent diffusion coefficient of acid dyes increased, and the apparent activation energies of diffusion decreased.