• Title/Summary/Keyword: UV-visible spectrometer

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Using Polypyrrole for Drug Delivery System (폴리피롤을 이용한 약물전달시스템)

  • Lee, Sang-Jo;Lee, Seung-Ki;Oh, Myung-Hwan;Park, Jung-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.448-451
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    • 2002
  • The possibility of using polypyrrole as a drug delivery system(DDS) has been studied using indicate (Phenol red) and substance with therapeutic activity(Sodium salicylate). In aqueous solution, negative potential is applied to polypyrrole then anion(with therapeutic activity) of sodium salicylate is released by redox processes of polypyrrole. The release amount of anionic drugs from polypyrrole is measured by UV-visible spectrometer which can measure UV-absorbance of materials. Electrode area that use for release amount measurement is$50mm^{2}(5{\times}10mm)$,and thickness of polypyrrole membrane is $15{\mu}m$. DC 1V applied in saline solution, the release amount according to time increased gradually. In various electrode area, release amount of anionic drug is directly to electrode area.

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Analysis of Germanium in the Ore Samples by UV-Visible Spectroscopy

  • Reddy, K. Raghava;Lee, Kwang-Pill;Gopalan, Anantha Iyengar;Showkat, Ali Md;Kim, Sang-Ho;Paek, U-Hyon
    • Analytical Science and Technology
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    • v.17 no.6
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    • pp.476-480
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    • 2004
  • A simple, rapid, reproducible and selective UV-Visible spectrophotometric method has been developed for determination of germanium in a week acid medium (pH = 3.0) in the presence of mandelic acid (MA) and malachite green (MG). A single extraction in chlorobenzene was used for the analysis. The germanium-MA ion association complex exhibits an absorption maximum at ${\lambda}_{max}=618nm$ with MG as counter ion and has an apparent molar absorptivtity of $1.313{\times}10^5L\;mol^{-1}\;cm^{-1}$. The values obtained by this UV-Visible spectrophotometric method are in good agreement with the values from inductively coupled plasma-mass spectrometer analysis.

Stability to the spreading solvent of(3-Alkyl benzimidazolium)-TCNQ(1:1) Complex for Langmuir-Blodgett Technigue (Langmuir-Blodgett법을 위한(3-Alkyl benzimidazolium)-TCNQ(1:1)착물의 분산용매 중에서의 안정성)

  • Sohn, Byoung-Chung;Hwang, Kyo-Hyun;Jeong, Soon-Wook
    • Journal of the Korean Applied Science and Technology
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    • v.11 no.1
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    • pp.39-44
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    • 1994
  • A Stability to the Spreading solvents, Which is acetonitrile, dichloromethane, benzene, chloroform and acetonitrile-benzene(1:1, v/v) of (3-Alkyl benzimidazolium)-TCNQ(1:1) Complex was investigated by UV-visible Spectrometer and was confirmed stabilized on acetonitrile, acetonitrilbenzene(1:1, v/v) for five hours. Using Ultra pure water as subphase for Langmuir-Blodgett (LB) Films, it was achived successively to fabricate the Y-type LB films of (3-Alkyl benzimidazolium)-TCNQ(1:1) Complex. For the identification of deposition of (3-Alkyl benzimidazolium)-TCNQ(1:1) Complex, UV-visible spectra was recorded on HP 8452A spectrometer.

Stability to the Spreading Solvent of (3-Alkyl Benzumidazolium)-TCNQ(l:2) Complex for Langmuir-Blodgett Technique (Langmuir-Blodgett법을 위한(3-Alkyl benzimidazolium)-TCNQ(1:2)착물의 분산용매 중에서의 안정성)

  • Jeoung, Soon-Wook;Hwang, Kyo-Hyun;Sohn, Byoung-Chung
    • Journal of the Korean Applied Science and Technology
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    • v.11 no.2
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    • pp.99-103
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    • 1994
  • A stability to the spreading solvent, which is acetonitrile, benzene, chloroform and acetonitrile-benzene(1:1, v/v) of (3-Alkyl benzimidazdium)-TCNQ(1:2) complex was investigated by UV-visible spectrometer and was confirmed stabilized on acetonitrile, acetonitrile-benzene (1:1, v/v) for five hours. Using Ultra pure water as subphase for Langmuir-Blodgett(LB) films, it was achived successively to fabricate the Y-type LB films of (3-Alkyl benzimidazolium)-TCNQ(1:2) complex. For the identification of (3-Alkyl benzimidazolium)-TCNQ(1:2) complex, UV-visible spectra was recorded on HP 8452A spectrometer.

Stability to the Spreading Solvent of (N-docosyl Quinolinium)-TCNQ(1:2) Complex by Langmuir-Blodgett Technique (Langmuir-Blodgett법을 위한(N-docosyl quinolinium)-TCNQ(1:2)착물의 분산용매 중에서의 안전성)

  • Jeoung, Soon-Wook;Lee, Yoong-Kook;Sohn, Byoung-Chung
    • Journal of the Korean Applied Science and Technology
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    • v.11 no.2
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    • pp.93-97
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    • 1994
  • A Stability to spreading solvent, which is acetonitrile, dichloromethane, benzene, chloroform, and acetonitrile-benzene (1:1, v/v) of (N-docosyl quinolinium)-TCNQ(1:2) complex was investigated by UV-visible spectrometer and was confirmed stabilized on acetonitrile, dichloromethane, and acetonitrile-benzene(1:1, v/v) for 7 hours. Using buffer solution($ph{\doteqdot}6.0$) as subphase for Langmuir-Blodgett(LB) film, it was achieved successively to fabricate the Y type LB films of (N-docosyl quinolinium)-TCNQ(1:2) complex. For the identification of deposition of (N-docosyl quinolinium)-TCNQ(1:2) complex, UV-visible spectra was recorded on HP 8452A spectrometer.

Measurements of Transmittances and Calculations of Fundamental Radiative Properties (투과율의 측정 및 이를 이용한 복사물성치의 계산)

  • Hwang, Yong-Ha;Park, Seung-Ho;Lee, Young-Soo
    • Solar Energy
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    • v.14 no.2
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    • pp.29-37
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    • 1994
  • Radiative charaacteristics of glass windows and porous absorbing media which can be used for a solar air heater are determined through the measurements of spectral transmittances. Those in the visible range are measured by the UV-IR spectrometer. Refractive index of glass are obtained by the comparison of the measured transmittances and the correlations derived from the electromagnetic theory and are compared to the theoretical ones calculated from the classical dispersion theory. Absorption and back-scattering coefficients of 15-mesh stainless wire screens are calcuated by the comparison of the measured transmittances and the correlations derived from the two flux model.

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Analysis on capacity loss caused by air oxidation of $V^{2+}$ ion using UV-Visible spectrophotometer for vanadium redox flow battery (공기 중 바나듐 2가 이온 산화에 의한 바나듐 레독스 흐름전지의 내구성 영향 분석)

  • Kwon, Soonkwan;Kim, Hansung
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.175.2-175.2
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    • 2011
  • 바나듐 3, 4, 5가 이온은 공기 중에서 안정하지만, 바나듐 2가 이온은 쉽게 산화된다. 그러므로 바나듐 2가 이온이 담겨져 있는 음극 탱크가 공기와 접촉하지 않게 하는 것이 중요하다. 충전 중 음극 탱크에 공기가 침투되면, 바나듐 2가 이온은 3가 이온으로 산화되기 때문에 음극과 양극의 전해질에 불균형을 초래한다. 이러한 불균형은 바나듐 레독스 흐름전지 용량저하의 원인이 된다. 본 연구에서는 공기 중 2가 이온 산화에 의한 전해질의 불균형 현상을 쉽게 보여주기 위해, 공기노출과 차단조건에서 충방전 중에 발생한 음극과 양극의 바나듐 이온 상태변화량을 UV-Visible spectrophotometer를 이용해 정량적으로 분석하였다. 분석 결과, 공기노출 조건에서 음극의 충전 시, 충방전 cycle이 진행 될수록 바나듐 2가 이온의 양이 현격히 줄어들었지만, 공기차단 조건에서는 2가 이온의 양이 공기노출 조건보다 훨씬 더 적게 줄어들었다. 즉, 공기차단 조건에서는 바나듐 2가 이온이 3가로 산화되지 않아서 음극의 충전 후 바나듐 3가에서 2가로 전환되는 양이 공기노출 조건보다 더 많은 것을 확인할 수 있었다. 이러한 영향으로 인해, 충방전 10th cycle을 진행해 본 결과, 공기차단 조건에서는 충방전 용량감소가 거의 없었지만 공기노출 조건에서는 현격한 충방전 용량 감소를 보였다.

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RF 스퍼터링 방법에 의한 AZO 투명전극용 박막에 대한 연구

  • 오데레사
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.886-887
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    • 2011
  • To obtain a transparent electrode, AZO thin film was deposited on SiOC film with various flow rates by rf magnetron sputtering system. SiOC film was deposited with various DMDMOS/O2 flow rate ratio by CVD, The optical electrical properties of the SiOC film and SiOC/AZO were analyzed by the uv visible spectrometer and 4 point prove system. The reflectance of SiOC/AZO film was changed in compared with that of SiOC film. The resistance was decreased with low RF power because of increasing the concentration of carriers.

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Anti-Reflection Coating Technology Based High Refractive Index Lens with Ultra-Violet Rays Blocking Function (반사방지 코팅기술 기반 자외선 차단 기능의 고굴절률 안경렌즈)

  • Kim, Ki-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.482-487
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    • 2016
  • Ultra-violet rays are very harmful to eye health care. The blocking of ultra-violet rays and a reduction of optical reflection in the visible light range, which is to increase the share of transmitted light, and avoid the formation of ghost images in imaging, are important for the applications of polymer eyeglasses lenses. In this study, the high-refractive index polymer lenses, n=1.67, were fabricated by injection-molded method with the xylene diisocyanate monomer, 2,3-bis-1-propanethiol monomer, and benzotriazol UV absorber (SEESORB 709) mixture. To reduce the reflection of the polymer lens surfaces, multi-layer anti-reflection (AR) coatings were coated for both sides of the polymer lens using an E-beam evaporation system. The optical properties of the UV blocking polymer lens were characterized using a UV-visible spectrometer. The material properties of the thin films, which were composed AR coating layers, refractive index, and surface roughness, were analyzed by ellipsometry and atomic force microscopy. As a result, the fabricated polymer lens perfectly blocked ultra-violet rays below 395 nm with a blocking rate greater than 99%.

Pitch Variations in Cholesteric Liquid Crystal Film by Molecular Diffusion (분자 확산에 의한 콜레스테릭 액정 필름의 피치 변화)

  • Kwon Young-Jin;Lee Won-Ju;Kim Beom-Kyung;Kim In-Sun;Song Ki-Gook
    • Polymer(Korea)
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    • v.30 no.5
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    • pp.422-425
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    • 2006
  • Due to their periodic helical structure, cholesteric liquid crystals (CLC) have a unique ability to selectively reflect visible light. CLC films reflecting a broad wavelength band were prepared by inducing a pitch gradient in CLC layers through a diffusion of small molecules and through a thermal mixing of cyclic siloxane CLC molecules with different pitch lengths. Various pitch gradients in the CLC cell were observed using UV/Vis spectrometer and SEM technique.