• 제목/요약/키워드: extent of reaction

검색결과 322건 처리시간 0.03초

Introduction of Carboxylic Acid Group onto Polyethylene Film By Electron Beam

  • Kang, Hae-Jeong;Park, Jang-Seong;Lee, Kwang-Pill;Park, Seong-Ho
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2000년도 춘계학술대회 논문집
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    • pp.139-141
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    • 2000
  • Carboxylic acid group was introduced onto polyethylene (PE) film by the grafting of acrylic acid onto PE film irradiated with electron beam. The grafting Condition such as reaction temperature, additives, total irradiation dose, thickness of PE film, and monomer concentration was examined. The extent of grafting was found to increase with increasing reaction temperature and total irradiation dose. The grafting yield was much enhanced with the addition of both FeSO$_4$ 7H$_2$O and H$_2$SO$_4$.

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Surface-Enhanced Raman Scattering of Benzenethiol Adsorbed on Silver-Exchanged Copper Powders

  • Shin, Kuan-Soo;Ryoo, Hyun-Woo;Lee, Yoon-Mi;Kim, Kwan
    • Bulletin of the Korean Chemical Society
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    • 제29권2호
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    • pp.445-449
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    • 2008
  • Micrometer-sized copper (mCu) powders are weakly surface-enhanced Raman scattering (SERS) active by the excitation at 632.8 nm, but nearly ineffective as a SERS substrate at 514.5 nm excitation. The SERS activity of mCu powders at both excitation wavelengths can be increased dramatically by a simple method of the galvanic exchange reaction with AgNO3 in aqueous medium. In this work, the SERS activity of the Ag-exchanged Cu powders (mCu@Ag) has been evaluated by taking a series of Raman spectra using benzenethiol (BT) as the probe molecule. It is clearly confirmed by field emission scanning electron microscopy and X-ray diffractometry that the SERS activity of mCu@Ag powders is, in fact, highly dependent on the extent of galvanic reaction.

세균성 Virus f2에 대한 Ozone의 불활성작용 (Action of Ozone on Bacterial Virus f2)

  • 김치경
    • 미생물학회지
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    • 제18권3호
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    • pp.123-132
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    • 1980
  • Bacterial virus f2 and its RNA were examined to elucidate the mode of ozone utilizing sucrose density gradient analysis and electtron microscopic techniques. the inactivation kinetics of the virus f2 by ozonation showed that the viruses were inactivated during the first 5 sec of the reaction and were further inactivated at a slower rate during the next 10 min at 0.09 and 0.8mg/l ozone concentrations. The virus coat was broken by ozonation into many pieces of protein subunits and the adsorption of the viruses to the host pili was inversely related to the extent of the breakage of the virus. The viral RNA was released from the virus particles during ozone, but ozone inactivation of the RNA enclosed in the protein coat could not ruled out the possibility that the RNA was secondarily sheared by a reaction with the broken coat protein.

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요추추나치료 후 발생한 등통증 환자 증례보고 (Dorsalgia occurred after Chuna Manual Theraphy : A Case Report)

  • 송영일
    • 척추신경추나의학회지
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    • 제9권2호
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    • pp.115-124
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    • 2014
  • Objectives: The purpose of this study is to investigate the safety, injury mechanism, complication and adverse reactions associated with Chuna manual theraphy(CMT), to report one case of adverse reaction with CMT. Methods: A 39-year-old woman presented with low back pain and left leg pain. The patient undertook a lumbar Chuna manual theraphy. After this maneuver, the patient complained of dorsalgia. The patient's dorsalgia didn't improve. In CT study, T5-6 hard disc bulging was diagnosed. Results and Conclusions : It is supposed that this patient suffered dorsalgia secondarily due to a lumbar Chuna manual theraphy. From this case, we can understand the etiology of dorsalgia to some extent and consider the complication of Chuna manual theraphy. In the future, more study, research and prospective trial for complications of a lumbar Chuna manual theraphy is required.

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충전층 반응기와 고정화 TiO2/UV를 이용한 Rhodamine B의 광촉매 탈색 (Photocatalytic Decolorization of Dye Using Packed-bed Reactor and Immobilized TiO2/UV System)

  • 김동석;박영식
    • 한국환경과학회지
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    • 제16권3호
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    • pp.255-260
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    • 2007
  • The photocatalytic decolorization of Rhodamine B (RhB) was studied using packed-bed reactor and immobilized $TiO_2/UV$ System. The 20 W UV-A, UV-B and UV-C lamps were employed as the light source. The effect of shape and surface polishing extent of reflector, distance between the reactor and reflector, reactor material were investigated. The results showed that the order of the initial reaction constant with reflector shape was round > polygon > W > rhombus. The optimum distance between the reactor and reflector was 2 cm. The initial reaction constant of quartz reactor was 1.46 times higher than that of tile PVDF reactor.

아크릴계 하이솔리드 도료의 Rheovibron에 의한 경화거동 연구 (Curing Behavior by Rheovibron of Acrylic High-Solid Coatings)

  • 김대원;황규현;김승진;우종표;박홍수
    • 한국응용과학기술학회지
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    • 제18권2호
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    • pp.142-152
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    • 2001
  • Acrylic resin(ACR) was blended with a curing agent, hexamethoxymethylmela-mine(HMMM), in which blending ratio was 70:30. The curing behavior was examined using Rheovibron. Cross-linking reaction started at $170^{\circ}C$ in 2 min of reaction and curing was completed in 10 min. It was found that the extent of cross-linking increased with the content of acetoacetoxyethyl methacrylate monomer in the ACR.

마우스에 있어서 카드뮴의 면역독성에 미치는 인삼석유 Ether 분획의 영향( I ) (Effect of Ginseng petroleum Ether Fraction on the Immunotoxicity of Cadmium in Mice (I))

  • 안영근;김정훈;이상근;황갑수
    • Environmental Analysis Health and Toxicology
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    • 제3권1_2호
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    • pp.43-54
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    • 1988
  • Experiment was performed to investigate the immunotoxicity of cadmium administered orally and the effect of ginseng petroleum ether fraction on it. Mice were given 3, 30, or 300 ppm cadmium as cadmium chloride orally in the drinking water and injection of ginseng petroleum ether fraction intraperitoneally for 4 weeks. Mice were sensitized and challenged with sheep red blood cells (S-RBC). Humoral immune response was evaluated by antibody production and Arthus reaction. Body weight gain, spleen weight, thymus weight, and liver weight were also measured. In the present study, cadmium generally suppressed the humoral immunity. There was decrease in the rate of body weight gain and liver weight to body weight by cadmium-administration. Ginseng petroleum ether fraction showed restoring effect, to some extent, on the decrease in PFC and in the rate of liver weight to body weight by cadmium-administration. But it more suppressed Arthus reaction.

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Enhancement of the Characteristics of Cement Matrix by the Accelerated Carbonation Reaction of Portlandite with Supercritical Carbon Dioxide

  • Kim, In-Tae;Kim, Hwan-Young;Park, Geun-Il;Yoo, Jae-Hyung;Kim, Joon-Hyung;Seo, Yong-Chil
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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    • pp.586-591
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    • 2001
  • This research investigated the feasibility of the accelerated carbonation of cement waste forms with carbon dioxide in a supercritical state. Hydraulic cement has been used as a main solidification matrix for the immobilization of radioactive and/or hazardous wastes. As a result of the hydration reaction for major compounds of portland cement, portlandite (Ca(OH)$_2$) is present in the hydrated cement waste form. The chemical durability of a cement form is expected to increase by converting portlandite to the less soluble calcite (CaCO$_3$). For a faster reaction of portlandite with carbon dioxide, SCCD (supercritical carbon dioxide) rather than gaseous $CO_2$, in ambient pressure is used. The cement forms fabricated with an addition of slated lime or Na-bentonite were cured under ambient conditions for 28days and then treated with SCCD in an autoclave maintained at 34$^{\circ}C$ and 80atm. After SCCD treatment, the physicochemical properties of cement matrices were analyzed to evaluate the effectiveness of accelerated carbonation reaction. Conversion of parts of portlandite to calcite by the carbonation reaction with SCCD was verified by XRD (X-ray diffraction) analysis and the composition of portlandite and calcite was estimated using thermogravimetric (TG) data. After SCCD treatment, tile cement density slightly increased by about 1.5% regardless of the SCCD treatment time. The leaching behavior of cement, tested in accordance with an ISO leach test method at 7$0^{\circ}C$ for over 300 days, showed a proportional relationship to the square root of the leaching time, so the major leaching mechanism of cement matrix was diffusion controlled. The cumulative fraction leached (CFL) of calcium decreased by more than 50% after SCCD treatment. It might be concluded that the enhancement of the characteristics of a cement matrix by an accelerated carbonation reaction with SCCD is possible to some extent.

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액정 고분자/에틸렌-아크릴산 이오노머 블렌드의 반응상용화에 관한 연구 (Reactive compatibilization of liquid crystalline polymer/ethylene-acrylic acid ionomer blends)

  • 하이디 크루즈;손영곤
    • 한국산학기술학회논문지
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    • 제16권5호
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    • pp.3653-3659
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    • 2015
  • 방향족 열방성 액정 고분자와 에틸렌-아크릴 산 공중합체 및 그 금속염 고분자간의 반응 상용화에 관하여 연구하였다. 블렌드는 배치 믹서에서 제조하였으며 액정 고분자의 에스터 그룹과 이오노머의 아크릴산 사이에 발생하는 acidolysis 반응으로 형성되는 그라프트 공중합체의 발생 유무를 평가하였다. 반응의 정도는 배치 믹서에서 시간에 따른 토크의 증가와 열분석 및 형태학 상 구조를 통해 평가하였다. poly(ethylene-co-acrylic acid) (EAA) 이오노머의 Na 염이 반응을 증진시키는데 특히 효과적임을 알 수 있었다. 반응의 진행 정도는 금속염의 종류 뿐 아니라 이오노머의 조성과 반응 시간에 따라 변하였다. 액정 고분자와 Na로 중화된 이오노머 간의 반응으로 생성된 그라프트 공중합체는 액정 고분자와 EAA 이오노머 블렌드의 반응상용화제로 효과가 높음을 미세 구조 분석을 통하여 알 수 있었다.

폴리프로필렌에 UV 흡수제를 갖는 말레이미드의 용융그래프팅 (Thermal Melt Grafting of Maleimides Having UV-absorber onto Polypropylene)

  • 김택현;나혜선
    • 폴리머
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    • 제38권1호
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    • pp.49-53
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    • 2014
  • 새로운 단량체형의 자외선흡수제를 triethylamine에서 2,4-dihydroxybenzophenone과 N-4-chlorocarbonyl-phenylmaleimide의 반응을 통하여 합성하였다. 이 자외선흡수제를 폴리프로필렌에 용융반응에 의해 그래프팅하였다. Maleimide의 그래프팅 수율은 IR 분광 데이터를 이용하여 결정하였다. 용융반응의 최적조건을 구하기 위하여 반응온도 및 시간, 단량체의 농도의 변화에 대하여 그래프팅 수율을 구하였다. Weatherometer에서 IR 스펙트럼의 카보닐 지수를 이용하여 그래프트된 폴리프로필렌의 광산화 정도를 조사하였으며, 우수한 광산화 억제작용을 보였다.