• Title/Summary/Keyword: 화학적 효과

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Comparative Degumming Effects of Detergents on Silk Twill (견직물에 대한 화학정련제의 정련효과 비교연구)

  • ;A.B
    • Journal of Sericultural and Entomological Science
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    • v.29 no.1
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    • pp.57-63
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    • 1987
  • 견직물의 정련에 있어서 관행 정련제인 비누와 이태리 견직업계에서 사용하고 있는 3종의 화학정련제를 비교 시험하였다. 정련 견직물의 강신도와 염색성은 비누 정련과 화학정련제 간에 차이가 없었으나 견직유질의 변성과 관련되는 점도 및 아미노기(-NH2) 함량은 비누정련견이 화학정련제 정련견에 비하여 약간 증가 및 감소되었으며 표면 미세구조에 있어서도 비누 정련견이 비교적 불순물의 잔류가 적었고 3종의 화학정련제 중에서는 정련제 "S"에 의한 정련견에 불순물의 잔류가 가장 적게 보였다.가장 적게 보였다.

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Suppression of reactive oxygen species generation as a part of antioxidative effect of plant extracts (식물추출물 항산화효능 기전의 일부로서의 활성산소 발생 억제 효과)

  • Song, Seon Beom;Chung, Gu June;Jung, Hee Jin;Jang, Jung Yoon;Chung, Hae Young;Kim, Nam Deuk;Lee, Ji-Hyeon;Min, Kyungjin;Park, Sun Yeong;Kwak, Chung Shil;Hwang, Eun Seong
    • Korean Journal of Food Science and Technology
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    • v.53 no.6
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    • pp.706-714
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    • 2021
  • Chemical scavenging of reactive oxygen species (ROS) is considered a major mechanism of antioxidant effects, but preventing ROS generation can be more efficient in attenuating oxidative damage. In this study, the extracts of plants, Solanum lycopersicum, Ailanthus altissima, Equisetum arvense, and Oenothera biennis, were tested to determine whether their antioxidative effects are driven by the prevention of superoxide generation from mitochondria, a major ROS generator. While all the extracts efficiently attenuated the elevation of ROS levels in human fibroblasts and inflammation-induced mice, those of S. lycopersicum, A. altissima, and O. laciniata only suppressed mitochondrial ROS generation and reduced levels of lipofuscin and lipid peroxidation. Furthermore, the extracts of A. altissima and O. laciniata extended the lifespan of fruit flies. Our results suggest that plant extracts with anti-oxidative effects differ in their ability to prevent ROS generation, which may be associated with the attenuation of oxidative damage in cells and animal tissues.

Analysis of Thin Films for Semiconductor (반도체소자 박막 분석)

  • Oh, Teresa
    • Proceedings of the KAIS Fall Conference
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    • 2010.11a
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    • pp.73-75
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    • 2010
  • 층간 절연막으로 사용 가능한 SiOC 박막에 대하여 유전상수가 낮아지는 원인을 이온에 의한 분극과 전자에 의한 분극에 대하여 측정하였다. MIS 구조를 이용하여 전형적인 C-V 측적법에 의하여 유전상수를 구하였으며, 굴절률을 측정하여 전자에 의한 분극의 효과에 의한 유전상수를 측정하고 서로 비교하였다. SiOC 박막의 화학적인 특성은 FTIR 분석을 이용하였으며, FTIR 분석에서 디컨벌류션한 데이터는 탄소의 함량에 대한 변화를 구하였다. 탄소의 함량변화는 굴절률의 변화와 비슷한 경향성을 나타내었으나, 유전상수와는 반비례하였다. 전자에 의한 분극의 효과는 유전상수가 떨어지는 것에 큰 영향을 주지는 않았으며, 이온에 의한 분극의 효과가 SiOC 박막의유전상수를 낮게 하는 효과가 더욱 크게 나타났다.

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Hair Strengthening Effect of Silane Coupling and Carbodiimide Chemistry (카르보디이미드 반응과 실란 커플링을 이용한 모발강화 효과)

  • Son, Seong Kil;Choi, Wonkyung;Lim, Byung Tack;Song, Sang-hun;Kang, Nae Kyu
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.44 no.2
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    • pp.133-139
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    • 2018
  • Chemically damaged hair is vulnerable to external stimuli in daily life due to the weakened physical properties of the hair strand itself. The purpose of this work was to determine whether chemical conjugation between hair keratin proteins restores tensile strength and thus results inpreventing further deterioration under repeated combing. A model damaged hair tress was produced by a typical perm-process. Then, it was internally crosslinked by the bifunctional crosslinker (3-aminopropyl)triethoxysilane (APTES), via both silane coupling and carbodiimide chemistry. Physical properties, including tensile strength, Young's modulus, and plateau stress, were measured to verify the effect of internal crosslinking, and the existence of crosslinking was verified by Fourier transform infrared (FT-IR) spectroscopy. The degrees of hair breakage and split ends were evaluated by repeated combing-drying tests. Physical properties of chemically damaged hair were restored by internal crosslinking. Successful crosslinking of APTES via both silane coupling and carbodiimide chemistry was verified by FT-IR spectra. Prevention of breakage and split ends after repeated combing with heat was observed. Human hair can be weakened by chemical damage including perm-processing, so restoring such properties is a major issue in the hair care industry. This work shows that internal crosslinking of damaged hair via chemical conjugation would be a potent method to restore the healthy hair.

Trials for Developing the Measures to Reduce the Inoculum Sources of Apple White Rot (사과 겹무늬썩음병의 전염원 경감법 개발을 위한 시도)

  • 김대희;김이부;엄재열
    • Korean Journal Plant Pathology
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    • v.12 no.2
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    • pp.219-255
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    • 1996
  • 사과 겹무늬썩음병의 주 전염원은 가지 병반에서 형성되는 자낭포자 및 병포자이므로, 가지에서의 포자형성 또는 포자의 분산을 화학적 또는 물리적 방법으로 저해할 수만 있다면 효과적으로 병을 방제할 수 있을 것으로 생각했다. 전염원을 줄이기 위한 첫 번째 시도로 1992년 이른봄 가지에 형성된 사마귀를 호미로 제거한 결과, 병포자의 분산과 과실발병 억제효과에 있어서 무처리와 유의적인 차이가 인정되지 않았다. 두 번째 시도로 포자의 분산을 막기 위해 1993년 이른봄에 겹무늬썩음병에 걸린 가지를 비닐필름으로 감고 5월부터 9월까지 20일 간격으로 살균제를 살포한 결과, 통계적으로 유의성이 인정되는 병 방제효과가 있었고, 나무의 생육에 있어서도 콜크층이 이상 비대하는 것 이외에 별다른 이상이 없었다. 이 개념을 더욱 발전시켜 1994년 이른봄에는 병든 가지를 수용성 고분자 물질인 polyvinyl alcohol로 도포하고 수배 분산 포자의 수를 조사한 결과, 포자의 분산량이 크게 줄어져 실용화의 가능성이 시사되었다.

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Cabin Air Filter Media Produced by Needle Punching Process (니들펀치 공정에 의한 캐빈에어필터 여재의 제조)

  • Park, Seungkyu;Kim, Heonchang
    • Applied Chemistry for Engineering
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    • v.20 no.5
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    • pp.561-564
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    • 2009
  • Filter media finely interspersed with activated carbons were prepared by a needle punching process without using chemical binders. Their characteristics were investigated efficiently to abate environmentally harmful gas such as acetaldehyde, and were compared with those of cabin air filter coated with activated carbons by using chemical binders. These combination filters were installed on a vehicle fan placed in a test chamber of capacity similar to the interior volume of a commercially available passenger car, and the efficiency of acetaldehyde abatement was measured as a function of time. The filter utilizing chemical binders showed somewhat better performance for the elimination of acetaldehyde despite the adverse effect of the chemical binder that would clog the micropores of the activated carbons. It turned out that the needle punching process had the activated carbons agglomerated due to hydrophobic interactions, resulting in a relatively larger void area than that of the filter utilizing chemical binders.

A Simple Method for Synthesizing CdS Nanoparticles and Silver Coating of These particles (감마선을 이용한 CdS 나노입자합성과 간단한 은 코팅방법)

  • 이창열;박승한;최중길
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.02a
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    • pp.8-9
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    • 2003
  • 나노입자에 대한 연구는 최근 20여 년 동안 각광받는 연구주제가 되어오고있다. 이런 나노입자는 벌크와 분자 단위의 경계가 되며 또한 구속효과(confinement effect)에 의해서 입자의 크기에 의존하는 광학적 성질을 갖는다. 이런 나노 수준에서는 그 입자의 표면과 중심에 수백 또는 수천 개의 입자를 가지게 되고 이런 입자들이 보이는 새로운 화학적, 물리학적 성질들은 전자기학, 광학, 화학 또는 물리학 등의 다양한 분야에서 많은 응용의 가능성을 보이고 있다. (중략)

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A Study on Inorganic Chemical Treatment Method of Animal Wastes Using by Electroflotation for Recycle (전해부상 장치를 이용한 축산폐수의 유기질비료와 용수 재활용에 관한 연구)

  • Sung Ki-chun;Kim Yong-Ryul;Kim Ki-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.5 no.6
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    • pp.588-591
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    • 2004
  • There is an increasing interest in the use of electrochemical methods for the animal waste treatment The technologies using the electrochemical method provide ideal tools for approaching industrial and animal wastes problems. Unlike other chemical treatments, the electrochemical systems do not make the volume of the secondary waste increase. The electrochemical methods can be operated with electrochemical apparatus and inorganic agent allow selective separation and recovery and even quieter than others. This study concerns design factors, electrode construction and wastewater treatment process of the electrochemical apparatus. The experiment of color, COD and BOD removal is much effective in using electrochemical method with ultrasonication and ozonation.

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Efficacy of Cu(II) Adsorption by Chemical Modification of Pine Bark (소나무 수피의 화학적 처리에 의한 Cu(II) 흡착 효과)

  • Park, Se-Keun;Kim, Ha-Na;Kim, Yeong-Kwan
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.8
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    • pp.930-937
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    • 2007
  • Korean pine(Pinus densiflora) bark was evaluated for its adsorption capacity of Cu(II) ions from aqueous solution by running a series of batch experiments. Prior to the tests, the milled barks were treated with 1 N NaOH or 1 N HCl to examine the effect of surface modification. For comparison, untreated bark was tested under same condition. Within the tested pH range between 3 and 6, NaOH treatment increased Cu(II) adsorption capacity by $139\sim184%$, while HCl treatment decreased it by $37\sim42%$. Maximum copper ion uptake by bark was observed at pH $5\sim6$, but pH of solution was not a potent influence. A pseudo second-order kinetic model fitted well for the sorption of copper ion onto bark. For NaOH-treated bark, the calculated sorption capacity$(q_e)$ increased from 6.58 to 12.77 mg/g, while the equilibrium rate constant$(k_2)$ decreased from 0.284 to 0.014 g/mg/min as initial Cu(II) concentration doubled from 100 mg/L. A batch isotherm test using NaOH-treated bark showed that equilibrium sorption data were represented by both the Langmuir model and the Freundlich model. It was confirmed that carboxylic acid of bark was involved in the Cu(II) adsorption. For NaOH-treated bark, in particular, carboxylate ion produced by hydrolysis or saponification appeared to be a major functional roup responsible for the enhanced Cu(II) sorption.