• 제목/요약/키워드: Nonionic

검색결과 401건 처리시간 0.029초

Ionic 또는 Nonionic Side Group을 갖는 Polyaniline Suspension의 전기유변특성 (Electrorheological Characteristics of Suspensions composed of Polyaniline Derivatives with Ionic or Nonionic Side Groups)

  • 조민성;김지우;장원휴;서문석;신민재;최형진
    • 유변학
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    • 제11권2호
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    • pp.91-96
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    • 1999
  • 반전도성 polyaniline의 유도체들로서 poly(aniline-co-sodium diphenylamine sulfonate), poly(aniline-co-o-ethoxyaniline), poly(o-methylaniline), poly(o-methoxyaniline)를 중합하여 전기유변유체의 입자로 사용하였다. 각 분산액은 전기장하에서 전형적인 전기유변특성을 나타냈으나, 낮은 전단변형률에서의 stress plateau 영역에서 입자의 종류에 따라 다른 흐름특성을 얻었다. 전기유변유체의 전기장에 따른 flow curve 변화와. dynamic yield stress와 전기장 간의 관계로부터 접근한 scaling law를 이용하여 각 전기유변유체의 universal flow curve를 구하였다.

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Emulsification of Chloroprene Rubber (CR) by Interfacial Chemistry; Stabilization and Enhancement of Mechanical Properties

  • Lee, Eun-Kyoung
    • Elastomers and Composites
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    • 제52권4호
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    • pp.257-265
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    • 2017
  • In this work, CR (Chloroprene Rubber) was emulsified by phase-inversion emulsification with nonionic surfactants (NP-1025, LE-1017, and OP-1019) and an anionic surfactant (SDBS; sodium dodecylbenzenesulfonate), and its stabilization was investigated through a study of its adsorption characteristics, zeta potential, and flow behavior. As the amount of the mixed surfactant increased, the droplet size decreased, resulting in the increase of viscosity. In particular, a CR emulsion with a lower absorbance in the UV spectrum exhibited the highest zeta potential. The results of this experiment showed that the CR emulsion prepared using (LE-1017) and SDBS was the most stable. In this study, calcium hydroxide and aluminum hydroxide were added to enhance the mechanical properties of the CR emulsion, and the relationship between tensile strength, tear strength and surface free energy were investigated. The tensile and tear strengths of the CR emulsion incresed as the amount of calcium hydroxide and aluminum hydroxide increased. The highest tensile and tear strengths and surface free energy were observed for additions of 1.0% calcium hydroxide and 0.80% aluminum hydroxide, respectively. It was concluded that the interfacial bonding strength was improved by the even dispersion of calcium hydroxide and aluminum hydroxide in the CR emulsion.

비이온 계면활성제인 SPAN 20 이 Rhodococcus sp. Strain IGTS8을 이용한 미생물 탈황공정에 미치는 영향 (Effect of Nonionic Surfactant SPAN 20 on the Biodesulfurization Process by Rhodococcus sp. strain IGTS8)

  • 박홍우;박기돈;오성근
    • KSBB Journal
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    • 제17권3호
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    • pp.295-301
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    • 2002
  • 본 연구에서는 Rhodococcus sp. strain IGTS8을 이용한 미생물 탈황공정에 있어서 비이온 계면활성제인 SPAN의 영향을 조사하였다. 탈황 효율 연구에 있어서 모델 오일로는 DBT가 함유된 hexadecane, 수상으로는 배지 용액을 이용하였다. 연구에 있어서 실험 변수로는 오일/물 혼합물에 있어서 오일의 부피 %, SPAN 20의 농도, 용액의 pH로 하였으며 일반적으로 오일의 부피 비율, 계면활성제의 농도가 증가할 수록 탈황 효율이 감소되었다. 이러한 결과는 오일의 부피비가 증가할수록 계면활성제의 농도가 증가할수록 오일상의 OBT와 균주의 효율적인 접촉이 저해되기 때문으로 고려된다.

효소에 의한 초지용 펠트의 세척효과 (Cleaning Effect of Papermaking Felt with Enzymes)

  • 윤병태;김성보;엄태진;최명재
    • 펄프종이기술
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    • 제37권3호
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    • pp.17-22
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    • 2005
  • The cleaning efficiency of papermaking felt which is contaminated with fiber fines and various micro-materials was investigated and compared between the application of enzyme and commercial detergent. It was found that the cleaning efficiency by the treatment of acidic-based detergent was more efficient than that of alkaline-based one in the conventional commercial detergent. it was also observed that the treatment design of first acidic-based detergent treatment to second alkaline-based detergent procedure was better in the cleaning efficiency, compared to alkaline based-to-acidic based one. The cleaning property of felt with enzyme was resulted in good cleaning efficiency, without any addition of surfactant. Especially, the enzyme treatment under alkaline condition (pH 10) showed a better cleaning result than that under acidic condition(pH 5). The addition of nonionic surfactant to the enzyme increased the cleaning efficiency of felt and decreased the cationic demand of wastewater. These results showed more favour than the application of conventional commercial detergent.

계면활성제(界面活性劑)의 약해유발농도(藥害誘發濃度)와 그 증상(症狀) (The Minimum Concentrations of Surfactants Inducing Phytotoxicity and Their Symptoms)

  • 유주현;구석진;조광연
    • 한국환경농학회지
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    • 제8권2호
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    • pp.119-127
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    • 1989
  • 1) 모든 처리에서 공히 가장 낮은 농도에서 약해를 유발한 계면활성제는 LE, NP, LN, SDSS, PAAS 및 DBC였으며, Tween, Span, SP, SC, STPP 및 CLIS 등은 고농도에서 약해유발이 가장 적었다. 2) 논담수상태에서는 음이온계면활성제가 비이온 계면활성제보다 낮은 농도에서 약해를 유발하였으나 그 밖의 처리에서는 거의 유사한 경향이었다. 3) 벼와 피는 약해에 있어서 거의 동일한 반응을 보였으며 각 초종간에 반응의 차이는 거의 없었다. 4) 밭상태와 건답상태의 발아전 처리에서는 10%이상의 고농도 시료에서도 약해유발이 매우 적었으나 논담수상태의 발아전 처리에서는 모든 처리 중 가장 낮은 농도에서 약해가 유발되었다.

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양친매성 2-butoxyethanol과 물 혼합계에서의 과잉 엔탈피 및 활동도 계수 (Excess Enthalpies and Activity Coefficients for the Binary Nonionic Amphiphile 2-Butoxyethanol/Water System)

  • 임경희
    • 한국응용과학기술학회지
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    • 제17권2호
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    • pp.132-138
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    • 2000
  • Excess enthalpies ($H^{E}$) were measured by isothermal flow calorimetry for the nonionic amphiphile 2-butoxyethanol/water mixtures at 10 different temperatures (48.5 to $70^{\circ}C$) around and above the lower consolute solution temperature, $T_{lc}$. $H^{E}$ exhibits U-shape for the binary mixtures, and is large and negative which reflects substantial interaction between two chemical species. When the commonly used, semi-empirical Redlich-Kister (RK) polynomials were fitted to the measured $H^{E}$, plots of $H^{E}$ vs. weight fraction provided more accurate fitting with fewer parameters than conventionally drawn $H^{E}$ vs. mole fraction plots. This was due to the enhanced symmetry of $H^{E}$ vs. weight fraction plots. Using the fitted Redlich-Kister polynomials and the Gibbs-Helmholtz relation, temperature dependence of the activity coefficients were found and compared to the values determined from vapor-liquid equilibria. The activity coefficients were in the range of one to three, indicating that the binary system deviates from ideality but not substantially. They slightly depended on temperature and the temperature effect was equivalent to 10 % change in the activity coefficients.

L-Menthol 수용액의 가용화에 미치는 에탄올의 영향 (Effects of Ethanol on Solubilization of L-Menthol Solution)

  • 지현;최형철;정노희
    • 한국응용과학기술학회지
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    • 제29권3호
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    • pp.365-369
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    • 2012
  • 본 연구에서 L-menthol 용액의 가용화에 미치는 에탄올의 영향을 연구하였다. L-menthol 용액은 1 mM L-menthol 수용액에 비이온 계면활성제인 PEG-40 Hydrogenated Castor Oil과 PEG-60 Hydrogenated Castor Oil을 가한 후, 에탄올의 농도를 변화시키면서 첨가하여 제조하였다. 제조한 용액의 입자크기와 표면장력을 측정하여 가용화에 미치는 에탄올의 영향에 대해 알아보았다. 에탄올의 함량이 증가할수록 입자크기와 표면장력이 감소하는 것을 확인하였다.

Anaphylactic Shock Following Nonionic Contrast Medium during Caudal Epidural Injection

  • Lee, Sang Hyun;Park, Jae Woo;Hwang, Byeong Mun
    • The Korean Journal of Pain
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    • 제28권4호
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    • pp.280-283
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    • 2015
  • Caudal epidural injection is a common intervention in patients with low back pain and sciatica. Even though the complications of fluoroscopically directed epidural injections are less frequent than in blind epidural injections, complications due to contrast media can occur. We report a case of anaphylactic shock immediately after injection of an intravenous nonionic contrast medium (iohexol) during the caudal epidural injection for low back pain and sciatica in a patient without a previous allergic history to ionic contrast media (ioxitalamate). Five minutes after the dye was injected, the patient began to experience dizziness, and the systolic blood pressure dropped to 60 mmHg. Subsequently, the patient exhibited a mild drowsy mental state. About 30 minutes after the subcutaneous injection of 0.2 mg epinephrine, the systolic blood pressure increased to 90 mmHg. The patient recovered without any sequela. Life-threatening complications after injection of intravenous contrast medium require immediate treatment.

폴리글리세롤을 친수성기로한 비이온성 계면활성제의 용액성 (Solution Properties of Polyglycerol Alkyl Ether Nonionic Surfactant)

  • 윤영균;남기대;강태준
    • 한국응용과학기술학회지
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    • 제9권2호
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    • pp.107-117
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    • 1992
  • The synthesis and solution properties of polyglycerol alkyl ether($R_{12}Gn$) are described. The phase behavior, surface tension, cloud point and HLB value of polyglycerol dodecyl ether in aqueous solution and in mixed solution of surfactant /water /oil have been investigated and compared with values of polyoxyethylene dodecyl ether. The surface tension showed that $R_{12}Gn$ have sufficiently low values of surface tension and cmc to serve as useful polyoxyethylene alkyl ether. The mesophases appearing in the $R_{12}Gn$ systems were more stable in a high temperature range than the mesophases of polyoxyethylene alkyl ether systems. The cloud point and HLB data indicated that addition of one glycerol group was equivalent to the addition of three oxyethylene group units, as far as the hydrophilic property was concerned. The phase diagrams of the polyglycerol alkyl ether /dodecane /water systems showed that the solubilizing and emulsifying powers of $R_{12}Gn$ were greater than those of polyoxyethylene alkyl ether. It is concluded that the polyglycerol chain can be even more useful as hydrophilic group of nonionic surfactants than the polyoxyethylene chain.