• Title/Summary/Keyword: water monolayer

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Utilization of Cotton Stalks-Biomass Waste in the Production of Carbon Adsorbents by KOH Activation for Removal of Dye-Contaminated Water

  • Fathy, Nady A.;Girgis, Badie S.;Khalil, Lila B.;Farah, Joseph Y.
    • Carbon letters
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    • v.11 no.3
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    • pp.224-234
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    • 2010
  • Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste, i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOH to semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by $N_2$-adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively. Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate the adsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highly microporous structure with high surface area of 950 $m^2/g$, total pore volume of 0.423 $cm^3/g$ and average pore diameter of 17.8 ${\AA}$. The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. The kinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that such laboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.

Surface Structure Image of Stearic acid Organic Thin Films (Stearic acid 유기박막의 표면주고 Image)

  • Chang, Hun;Song, Jin-Won;Choi, Young-Il;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.562-564
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    • 2001
  • Transformation of molecular film occurs only usually in air-water interface, 2 dimensions domain's growth and crash are achieved. Organic matter thin film that accumulate molecular film in archaism board only that consist of growth of domain can understand correct special quality of accumulation film supplying information about fine structure and properties of matter of device observing information and so on that is surface forward player and optic enemy using AFM one of SPM application by nano electronics. The stable images are probably due to a strong interaction between the monolayer film and glass substrate. We are unable to obtain molecule resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it. Formation that prevent when gas phase state and liquid phase state measure but Could know organic matter that molecules form equal and stable film when molecules were not distributed evenly. and accumulated in solid state only.

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A Study on the Electrical Physical Properties of Organic Thin Films for Manufacture in Power Device

  • Song, Jin-Won;Lee, Kyung-Sup
    • Transactions on Electrical and Electronic Materials
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    • v.6 no.1
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    • pp.18-21
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    • 2005
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understanding of the relationship between the structure and function of the monolayers. Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuirfilms. MDC flowing across monolayers is analyzed using a rod-like molecular model. A linear relationship between the monolayer compression speed a and the molecular area Am. Compression speed a was about 30, 40, and 50 mm/min. Langmuir-Blodgett(LB) layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film. The structure of manufactured device is Aul Arachidic acid! AI, the number of accumulated layers are $9{\sim}21$. Also, we then examined of the Metal-Insulator-Metal(MIM) device by means of I-V. The I-V characteristics of the device are measured from -3 to+3 V. The insulation property of a thin film is better as the distance between electrodes is larger.

A Study on the Image and Surface Structure analysisthat Manufacture by LB Method of LB Thin Film (LB박막의 이미지와 표면구조분석에 관한 연구)

  • Song, Jin-Won;Lee, Kyung-Sup;Choi, Young-Il;Chung, Hun-Sang;Gu, Hal-Bon;Kim, Young-Keun;Lee, Young-Gil
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1618-1620
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    • 2002
  • Transformation of molecular film occurs only usually in air-water interface, 2 dimensions domain's growth and crash are achieved. Organic matter thin film that accumulate molecular film in archaism board only that consist of growth of domain can understand correct special quality of accumulation film supplying information about fine structure and properties of matter of device observing information and so on that is surface forward player and optic enemy using AFM one of SPM application by nano electronics. The stable images are probably due to a strong interaction between the monolayer film and glass substrate. We are unable to obtain molecule resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it. Formation that prevent when gas phase state and liquid phase state measure but Could know organic matter that molecules form equal and stable film when molecules were not distributed evenly, and accumulated in solid state only.

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Synthesis and Characterization of Artificial Skin based on Polypeptides (Polypeptide계 인공 피부의 합성과 특성)

  • Kim, Seon-Jeong;Min, Dong-Seon;Kim, Gye-Yong
    • Journal of Biomedical Engineering Research
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    • v.8 no.1
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    • pp.87-92
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    • 1987
  • In order to evaluate the artificial skin for burn would covering materials, copoly(N. carbobenzoxy-L-Iysine-L-leucine)s were prepared by Ipolymerization of N - carbobenzoxy-L- I sine anhydride and L-leucine anhydride in homogeneous solvents using triethylamine as an initiator. The synthetic polypeptides and the oxter type polyurethane(PV)of medical grade were used as the sheet type membranes were prepared ; monolayer membrances were composed of only the polypeptides, bilayer membranes and blend membranes were controlled by composition of the polypeptides and PU. Test of the swelling degree, mechanical tensile strength, elongation, oxygen permeability, water-vapor loss and In vitro degradation treated by pretense TV of samples of artificial skin were measured by adequate methods so as to mechanical, physincal characterization and biodegradation. As a result, all the values of samples were found to be similar to desired value of skin which was nature. The Artificial skin based on polypeptides can be considered as ideal burn wound covering materials.

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Electrical Properties of Organic Thin Film for Power Device (전력 소자용 유기박막의 전기적 특성)

  • Song, Jin-Won;Choi, Yong-Sung;Moon, Jong-Dae;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.05a
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    • pp.20-22
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    • 2006
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understanding of the relationship between the structure and function of the monolayers. Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuir-films. MDC flowing across monolayers is analyzed using a rod-like molecular model. A linear relationship between the monolayer compression speed and the molecular area Am. Compression speed was about 30, 40, 50mm/min. Langmuir-Blodgett(LB)layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film. The structure of manufactured device is Au/Arachidic acid/Al, the number of accumulated layers are 9~21. Also, we then examined of the Metal-Insulator-Metal(MIM) device by means of I-V. The I-V characteristics of the device are measured from -3 to +3[V]. The insulation property of a thin film is better as the distance between electrodes is larger.

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Dielectric Properties of Complex Cconcentration in IMI-0 Thin Films (IMI-O 초박막의 착체농도에 대한 유전 특성)

  • 정상범;유승엽;박재철;권영수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.345-348
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    • 1999
  • The monolayer behaviors at the air-water interface and the dielectric properties of MI-0 LB films for complex concentration were investigated by the surface pressure-area ($\pi$-A) isotherms and dielectric constant. The molecular area was expanded with increase of metal ions concentration. It is considered that the expansion of molecular area is due to electrostatic repulsion between the polymer chains andhydrophobic increase of ionic strength. In the frequency-dependent complex dielectric constant at room temperature, the real part of dielectric constant($\varepsilon'$) is about 6.0~10.0 in the low-frequency range and is decreasing slowly upto $1O^4$Hz. It decreased abruptly near $1O^5Hz$. It seems to be dielectric dispersion in this frequency range. Also, the imaginary part of dielectric constant ($\varepsilon"$) shows a peak in $1O^5$~$1O^6Hz$. It seems to be dielectric absorption in this frequency range.ange.

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Surface Analysis and Electrical Properties for Complex with Concentration of Metal ion in LB Ultra-thin Films Using IMI-O Polymer (IMI-O 고분자 LB막의 금속 이온의 착체 농도에 따른 전기특성 및 표면분석)

  • Jung, S.B.;Yoo, S.Y.;Park, J.C.;Kwon, Y.S.
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1711-1713
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    • 2000
  • We fabricated an IMI-O polymer containing an imidazole group that could form a complex structure between the monolayer and the metal ions at the air-water interface. Also, the surface analysis and the electrical properties of metal ion complex of Langmuir-Blodgett (LB) films were investigated by using $\pi$-A isotherms. Atomoic force microscopy (AFM), current-voltage (I-V) measurements. In the $\pi$-A isotherms the molecular area was expanded with $Fe^{3+}$ concentration increase. It is considered that the expansion of molecular area is due to electrostatic repulsion between the polymer chains and hydrophobic increase of ionic strength. In the I-V characteristics, it is found that the limiting area has effects on the change of conductivity. And, the dielectric relaxation time decreased for increase of the $Fe^{3+}$ concentration.

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Surface Structure Image of Stearic acid Organic Thin Films (Stearic acid 유기박막의 표면구조 Image)

  • Chang, Hun;Song, Jin-Won;Choi, Young-Il;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2001.11a
    • /
    • pp.562-564
    • /
    • 2001
  • Transformation of molecular film occurs only usually in air-water interface, 2 dimensions domain's growth and crash are achieved. Organic matter thin film that accumulate molecular film in archaism board only that consist of growth of domain can understand correct special quality of accumulation film supplying information about fine structure and properties of matter of device observing information and so on that is surface forward player and optic enemy using AFM one of SPM application by nano electronics. The stable images are probably due to a strong interaction between the monolayer film and glass substrate. We are unable to obtain molecule resolution in images of the films but did see a marked contrast between images of the bare substrate and those with the network structure film deposited onto it. Formation that prevent when gas phase state and liquid phase state measure but Could know organic matter that molecules form equal and stable film when molecules were not distributed evenly, and accumulated in solid state only.

  • PDF

A Study on the Electrical Properties of Organic Ultra Thin Films for Nanoscale Device Manufacture (나노스케일 소자제작을 위한 유기초박막의 전기적특성에 관한 연구)

  • Song, Jin-Won;Han, Chang-Su;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.384-385
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    • 2005
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understanding of the relationship between the structure and function of the monolayers. Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuir-films. MDC flowing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$ of mono layers in the isotropic polar orientational phase is determined using a liner relationship between the monolayer compression speed a and the molecular area $A_m$. Compression speed a was about 30, 40, 50mm/min. also, LB layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film. The structure of manufactured device is Au/Arachidic acid/Al, the number of accumulated layers are 9 ~ 21 and we then examined of the Metal-Insulator-Metal(MIM) device by means of I-V.

  • PDF