• Title/Summary/Keyword: 아마이드

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Hydrolytic degradation of Aliphatic Poly(ester-amide)s (지방족 폴리 에스터-아마이드의 가수분해 거동)

  • 이순열;박준욱;유영태;임승순
    • Proceedings of the Korean Fiber Society Conference
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    • 2001.10a
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    • pp.103-106
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    • 2001
  • 최근, 환경문제에 관한 관심이 고조됨에 따라서, 환경에 영향을 주지 않는 새로운 재료로서 분해성 고분자가 주목을 받고있다. 인위적인 방법으로 합성되어진 고분자 중에서, 주쇄에 ester group을 가지고 있는 즉, 미생물이나 물에 의해서 분해가 가능한 작용기를 가진 고분자가 실제 그 응용 가능성이 가장 높다. 하지만 그 자체만으로 범용 고분자를 대체 하기에는 열적. 기계적 특성이 상당히 낮다. (중략)

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Chlorine Disinfection in Water Treatment Plants and its Effects on Polyamide Membrane (수처리장에서의 염소살균처리가 폴리아마이드 분리막에 미치는 영향)

  • Jun, Byung-Moon;Yun, Eun-Tae;Han, Sang-Woo;Nguyen, Thi Phuong Nga;Park, Hyung-Gyu;Kwon, Young-Nam
    • Membrane Journal
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    • v.24 no.2
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    • pp.88-99
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    • 2014
  • Demand for water is increasing due to rapid population growth and increased industrial activities. Membrane technologies have attracted most attention as a promising advanced technology for the supply of sustainable water resources. Chemical and structural properties of polyamide membranes, one of the most widely used membranes in water treatment plant, has been reported to be affected by residual chlorine dissolved in water after chlorine disinfection. This paper focuses on the chlorine speciation at various solution pHs and change of surface properties/performance of polyamide membranes due to the chlorine exposure.

Influence of Temperature on Separation of CO and H2 Mixed Gas Using Polyamide Composite Membrane (폴리아마이드 복합막을 이용한 일산화탄소 및 수소 혼합가스의 분리특성에 대한 온도의 영향)

  • Choi, Kyung Seok;Poudel, Jeeban;Oh, Sea Cheon
    • Clean Technology
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    • v.18 no.4
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    • pp.360-365
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    • 2012
  • With rapid increase in municipal solid waste (MSW) due to the rising economy, solid waste gasification emerges as one of the promising technologies. Separation of the carbon monoxide (CO) and hydrogen ($H_2$) from syngas obtained by gasification of MSW was studied using the polyamide composite membrane. The separation characteristics of the CO and $H_2$ were studied at different gas flow rates and stage cuts. The permeability of CO and $H_2$ along with the selectivity of $H_2$ with respect to CO was obtained. Furthermore, the Arrhenius plots were obtained to estimate the activation energies of CO and $H_2$ permeabilites.

Processing and Characterization of Polyamide 610/Carbon Fiber/Carbon Nanotube Composites through In-Situ Interfacial Polymerization (계면중합법을 이용한 폴리아마이드 610/탄소섬유/탄소나노튜브 복합재 제조 및 물성 평가)

  • Cho, Beom-Gon;Hwang, Sang-Ha;Park, Young-Bin
    • Composites Research
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    • v.33 no.6
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    • pp.415-420
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    • 2020
  • The interfacial properties in carbon fiber composites, which control the overall mechanical properties of the composites, are very important. Effective interface enhancement work is conducted on the modification of the carbon fiber surface with carbon nanotubes (CNTs). Nonetheless, most surface modifications methods do have their own drawbacks such as high temperatures with a range of 600~1000℃, which should be implemented for CNT growth on carbon fibers that can cause carbon fiber damages affecting deterioration of composites properties. This study includes the use of in-situ interfacial polymerization of polyamide 610/CNT to fabricate the carbon fiber composites. The process is very fast and continuous and can disperse CNTs with random orientation in the interface resulting in enhanced interfacial properties. Scanning electron microscopy was conducted to investigate the CNT dispersion and composites morphology, and the thermal stability of the composites was analyzed via thermogravimetric analysis. In addition, fiber pull-out tests were used to assess interfacial strength between fiber and matrix.

Design of Solid Lipid Nanoparticles to Improve Penetration of Niacinamide through Artificial Skin Tissue (나이아신아마이드의 인공피부조직 투과 개선을 위한 고형지질나노입자의 설계 연구)

  • Yeo, Sooho
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.2
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    • pp.133-138
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    • 2021
  • In this study, Niacinamide (NI) was loaded into solid lipid nanoparticles (SLNs) and skin permeability was evaluated to improve skin permeability of NI, which was a skin whitening substance. NI was able to effectively load within SLN with a double-melting emulsification method, producing stable particles with average particle sizes of 263.30 to 436.93 nm and a zeta potential of -34.77 to -57.60 mV. Artificial skin tissue (SkinEthicTM RHE) derived from skin keratinocytes derived from human epidermal tissue was used for the skin permeation study of NI. Skin transmittance and deposition experiments of NI confirmed that all SLN formulations improved skin transmittance and deposition rates of NI, approximately 5.4 ~ 7.6 and 9.5 ~ 20.8 improvement over SLN applications. Therefore, SLN manufactured in this study have shown sufficient results to improve the skin permeability of the functional whitening substance, NI.

Comparison of Reduced Acrylamide Formation in Chips Fermented with Different Cultivar Potatoes by Bacillus subtilis (Bacillus subtilis를 이용한 발효 감자 칩의 감자 품종에 따른 아크릴아마이드 저감화 비교)

  • Yeo, Seoungsoon;Yim, Sangeun;Jin, Yong-Ik;Chang, Dong-Chil;Chang, Yoon Hyuk;Lee, Youngseung;Jeong, Yoonhwa;Kim, Misook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.6
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    • pp.744-750
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    • 2017
  • Acrylamide is a probable human carcinogen and can be formed during frying of starchy foods. The objective of this study was to investigate the effects of acrylamide reduction in storage potato chips by fermentation of Bacillus subtilis and compare its usefulness with four different cultivars of storage potatoes (Goeun, Atlantic, Saebong, and Jinsun). Potato slices were fermented by B. subtilis at $37^{\circ}C$ for 0, 2, and 4 h and fried at $180^{\circ}C$ for 115 s. The total sugar contents of the fermented potato slices did not change compared to the control. However, reducing sugar contents increased in the fermentation solution containing potato slices. Asparagine contents of Saebong and Jinsun potato slices decreased with fermentation time. Color values of the fermented potato chips were improved compared to those of non-fermented potato chips. The highest $L^*$ value was found in Saebong (57.4), followed by Goeun (56.7), Jinsun (52.5), and Atlantic (48.8) after 4 h of fermentation. Potatoes stored for 240 days generated considerable amounts of acrylamide, ranging from 4.99 to 10.38 ppm, after frying. Four hours of fermentation reduced acrylamide formation in all potato chips. The lowest acrylamide content was found in Saebong (0.77 ppm), followed by Jinsun (1.21 ppm), Goeun (1.76 ppm), and Atlantic (4.09 ppm). In conclusion, fermentation of storage potatoes by B. subtilis can effectively lower acrylamide formation during frying of potato chips.

Preparation and Characteristics of Liquid Silicone Rubber Using Polyorganosiloxane Modified with Dimethylacrylamide (디메틸아크릴아마이드 변성 폴리오가노실록산을 이용한 액상 실리콘 고무의 제조와 그 특성)

  • 강두환;이병철
    • Polymer(Korea)
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    • v.28 no.2
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    • pp.143-148
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    • 2004
  • ${\alpha}$,$\omega$-Hydrogen polyorganosiloxane(HPMDMS) prepolymer was prepared from equilibrium polymerization ofoctamethylcyclotetrasiloxane, 1,3,5-trimethylcyclotrisiloxane, 1,3,5,7-tetravinyl-1,3,5,7-tetramethyl-cyclotetrasiloxane, and 1,1,3,3-tetramethyl disiloxane as an end-blocker in the presence of tetramethylammonium siloxanolate as a catalyst. Polyorganosiloxane modified with dimethylacrylamide(APMDMS) was prepared by hydrosilylation of HPMDMS with dimethylacrylamide in the presence of Pt catalyst, and followed by coordination of metal oxide (APMDMS-MO), such as NiO and FeO, to the amide moieties of the resulting polymer. The chemical structures of HPMDMS and APMDMS were confirmed by FT-IR and $^1$H-NMR analysis. Liquid silicone rubber containing metal oxide composite (LSRMO) was prepared by compounding APMDMS-MO, ${\alpha}$,$\omega$-vinylpolydimethylsiloxane, and a catalyst in a high speed dissolver. The thermal conductivity of LSRMO composite was determined to be 0.29 W/mK, and the volume resistivity exhibited a lower value than that of LSR composite. The mechanical and thermal properties of LSRMO and LSR composite were measured by UTM and TGA.