• Title/Summary/Keyword: 아민

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Preparation and Characteristics of PCL/Chitosan Composites by Melt Blend (용융블렌드를 이용한 PCL/Chitosan복합체의 제조 및 특성)

  • 윤철수;송민수;지동선
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10b
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    • pp.163-164
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    • 2003
  • 키토산은 셀룰로오스 다음으로 자연계에 많이 존재하는 천연 고분자인 키틴을 탈아세틸화 시킨 것으로서, 많은 아민기를 가지고 있는 것이 특징이다[1]. 키토산은 아민기에 의한 항균성이 뛰어나기 때문에 섬유제품의 항균 가공제로 이용되고 있다. 그러나 키토산은 다른 천연고분자와 마찬가지로 용융가공성이 없기 때문에 섬유, 멤브레인 등으로의 성형은 묽은 산 수용액으로 만든 용액을 가공하는 방법을 이용하고 있다. (중략)

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Effect of Amine Compounds on Electrical Properties of Graphene Oxide Films made by Bar Coating (바코팅에 의해 제조된 그래핀 옥사이드 필름의 전기적 특성에 미치는 아민 화합물의 영향)

  • Choi, Jin Whan;Lee, Seul Bi;Lee, Seong Min;Park, Wan-Su;Chung, Dae-Won
    • Applied Chemistry for Engineering
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    • v.26 no.3
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    • pp.331-335
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    • 2015
  • We prepared films by a bar-coating of various graphene oxide (GO) pastes by varying pH with amine compounds. The thermal treatment of films at $150^{\circ}C$ and measurement of surface resistances exhibited that the pH variation does not significantly affect the surface resistance. We, however, found that the addition of amines reduced the surface resistance by approximately 10 times and N,N-dimethylethanolamine (DMEA) showed the most significant effect among all amines investigated. XPS studies demonstrated that the addition of DMEA accelerated the reduction reaction of GO, and finally enhanced the electrical properties of GO films.

Effects of Inorganic-organic Additives on CO2 Adsorption of Activated Carbon (활성탄의 이산화탄소 흡착에 미치는 유무기계 첨가제의 영향)

  • Jo, Dong-Hyun;Cho, Ki-Sook;Park, Cheong-Gi;Kim, Sung-Hyun
    • Korean Chemical Engineering Research
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    • v.50 no.5
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    • pp.885-889
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    • 2012
  • In this study, amine and metal oxide additives were investigated to improve $CO_2$ adsorption capacity of activated carbons (ACs). The characteristics of surface modified ACs were studied by X-ray photoelectron spectroscopy (XPS), $N_2$ adsorption, X-ray diffraction (XRD), and BET. Amine surface treatment decreased specific surface area and pore volume of ACs, but increased alkalinity by the incorporated nitrogen functional groups. Adsorption capacities of amine functionalized ACs was larger than original ACs, because basic group which can react with $CO_2$ was grafted on the ACs surface. Presence of copper oxides on ACs also enhances the carbon dioxide adsorption. The copper oxides could increase the adsorption rate of carbon dioxides due to the acid-base interaction (or electron acceptor-donor interaction). It was found that copper oxide loading was a promising method to improve the $CO_2$ adsorption capacity of ACs.

Synthesis and Determination of Optical Purity of C2-Symmetric Pyrrolidine Amides as Chiral Auxiliaries (키랄 보조제로서의 C2-대칭성 피롤리딘 아미드의 합성과 광학 순도 결정)

  • Moon, Hong-sik;Koh, Dongsoo
    • Applied Chemistry for Engineering
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    • v.9 no.6
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    • pp.914-919
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    • 1998
  • Optically pure $C_2-Symmetric$ pyrrolidine amides (8) were synthesized from readily available 1,2:5,6-di-O-isopropylidene-D-mannitol (1). Cyclization of dimesylated hexitol (4) with benzyl amine gave an inseparable mixture of $C_2-Symmetric$ pyrrolidine amine derivative (5) as a major product, concurring with its cis isomer (6) as a minor product. The pyrrolidine amines (5,6) were converted to separable pyrrolidine amides (8,9) via free amine (7). Optical purity of desired $C_2-Symmetric$ pyrrolidine amide (8a) was determined with its Mosher derivatives (13,14) by their $^1H$ and $^{19}F$ NMR spectra.

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Microbial Degradation of Non-volatile-amine (미생물에 의한 불휘발성아민의 분해)

  • LEE Tae-Seek;PARK Jeong-Heum;LEE Myung-Suk;HUR Sung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.1
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    • pp.1-6
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    • 1990
  • The degradation of non-volatile-amines by microorganisms were investigated. The degra-ding activity could be noted in four strains isolated from fermented sardine sauce, and those were Pseudomonas aeruginosa, Pseudomonas fluorescens P-2, Pseudomonas fluorescens P-3 and Enterobacter aerogenes. The strongest degrading activity of non-volatile-amines was showed in Pseudomonas fluorescens P-3 among the four strains isolated. The optimum temperature for degradation by Pseudomonas fluorescens P-3 was $35^{\circ}C$, corresponding to the optimum temperature for growth of this strain, pH between 7.0 and 7.5 could gave effective degradation and the optimum concentration of NaCl was 0 and/or $1\%$.

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The Safety of Carcinogenic Heterocyclic Aromatic Amines from the Cooked Foods (식품의 조리.가공중 생성되는 발암성 이환방향족아민의 안전성)

  • 전향숙;김주연
    • Journal of Food Hygiene and Safety
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    • v.14 no.4
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    • pp.386-396
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    • 1999
  • Commonly eaten fish, meat and other protein-containing foods show some level of mutagenic activity following normal cooking such as broiling, frying, grilling, roasting etc. The main food mutagens found in cooked products are“heterocyclic aromatic amines”. Several of them have been shown to be carcinogenic in rodent and suggested to be relevant for human cancer etiology. This review summarizes the chemistry, formation, occurrence and toxicity of food-borne heterocyclic aromatic amines. Factors that influence the formation of them are also discussed with special emphasis on dietary factors. From a health safety point of view, it is desirable to estimate the intake of heterocyclic amines via foods, and reduce or prevent the formation of food mutagens.

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A Study on N-Nitrosodimethylamine (NDMA) Formation According to pH Variation (pH 변화에 따른 N-Nitrosodimethylamine (NDMA) 생성에 대한 고찰)

  • Kim, Jong-O;Clevenger, Thomas
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.4
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    • pp.390-393
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    • 2005
  • N-nitrosodimethylamine (NDMA), a potent carcinogenic, has recently been observed at drinking water supply systems in USA and Canada. The NDMA formation was studied as a function of chloramine concentration (0.001-0.1 mM) at a fixed dimethylamine (DMA) concentration of 0.05 mM at different initial pH (6, 7, 8). It was found that the NDMA formation rate varied with pH values. The formation of NDMA increased with increasing chloramine concentration and showed maximum yields of 2.4% and 1.6% at pH 7 and 8, respectively. A good correlation ($r^2>0.99$) was observed between the molar ratio (chloramine/DMA) and NDMA formation at pH 7 and 8. Linearity of the NDMA formation appeared to be related to chloramine concentrations.