• Title/Summary/Keyword: Molecular Characteristics

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Electrical Properties of IMI-O Polymer LB Films in Complexed Metal Ion (금속이온 착체에 의한 IMI-O 고분잔 LB막의 전기적 특성)

  • Jung, Sang-Burm;Yoo, Seung-Yeop;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 1997.07d
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    • pp.1519-1521
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    • 1997
  • In this paper, poly (N-(2-4-imidazolyl) ethyl) maleimide-alt-1-octadecene (IMI-O) polymer which can complex metal ion was used to confirm the possibility of molecular device made by Langmuir-Blodgett method. Metal/Insulator/Metal (MIM) device was fabricated for investigation of electric properties. In the ${\pi}$-A isotherm, surface pressure at collapse point was different as to the molecular weight of metal ion complexed respectively, In I-V characteristics, currents of MiM devices were different at the same voltage. It was thought that phenomena was occurred by interaction between function group and metal ion.

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Thermodynamic Characteristics of Blends Involving Polycarbonates and Various Polymethacrylates (폴리카보네이트들과 다양한 종류의 폴리메타아크릴레이트 블렌드의 열역학적 특성에 관한 연구)

  • 김주헌;박동식;김창근
    • Polymer(Korea)
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    • v.24 no.5
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    • pp.682-689
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    • 2000
  • The information related to the interaction energy between repeat units is essential for the production of useful polymer blends via molecular structure design. Based on the interaction energies obtained here, a method for the fabrication of miscible blend was suggested. An investigation related to the equilibrium phase behavior of polymer blends of various polycarbonates with various polymethacrylates was performed and then based on the obtained interaction information miscible polymer blends were produced by controling molecular structure of polymer. Binary interaction energies between repeat units were calculated from the lower critical solution temperature-type phase boundary using an equation of state combined with binary interaction model.

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Effects of Annealing on the Structural Deformation of Polyelectrolyte Complexes based on Two Anionic Polysaccharides

  • Kim, Sang-Gyun;Lee, Kew-Ho
    • Korean Membrane Journal
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    • v.10 no.1
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    • pp.39-45
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    • 2008
  • Polyelectrolyte complex based on two anionic polysaccharides, composed of sodium alginate and carrageenan, were prepared by interacting with divalent calcium ions in solution. The effects of annealing on the structural deformation of polyelectrolyte complex and on their characteristics at removing water from a methanol mixture from the point of molecular sieve were investigated and discussed. The result showed that the structural deformation of the annealed polyelectrolyte complex has an effect on the free volume between these polymer chains and the chelate segments such a shrinking of the overall morphology, which act as a molecular sieve in the separation of methanol and water mixtures.

Dielectric Relaxation Characteristics of Phospholipid Membrane (인지질막의 유전완화 특성)

  • 이경섭;조수영;박석순;정헌상;최영일
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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    • pp.173-176
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    • 1998
  • We experimentally investigated the dielectric relaxation phenomena of a liquid crystal monolayers by the Displacement current techique and displacement current flowing across monolayers is analyzed using rod-like molecular model. It is revealed that the dielectric reaxation time $\tau$ of monolaters in the isotropic polar orientational phase is determined using a linear relashionship between the monolayers compression speed $\alpha$ and the molecular area. The dielectric relaxation time of phospholipid monolayers was examined on the basis of the analysis developed here.

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A Database of Gene Expression Profiles of Korean Cancer Genome

  • Kim, Seon-Kyu;Chu, In-Sun
    • Genomics & Informatics
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    • v.13 no.3
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    • pp.86-89
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    • 2015
  • Because there are clear molecular differences entailing different treatment effectiveness between Korean and non-Korean cancer patients, identifying distinct molecular characteristics of Korean cancers is profoundly important. Here, we report a web-based data repository, namely Korean Cancer Genome Database (KCGD), for searching gene signatures associated with Korean cancer patients. Currently, a total of 1,403 cancer genomics data were collected, processed and stored in our repository, an ever-growing database. We incorporated most widely used statistical survival analysis methods including the Cox proportional hazard model, log-rank test and Kaplan-Meier plot to provide instant significance estimation for searched molecules. As an initial repository with the aim of Korean-specific marker detection, KCGD would be a promising web application for users without bioinformatics expertise to identify significant factors associated with cancer in Korean.

Intercalation of Vitamer into LDH and Their Controlled Release Properties

  • Choy, Jin-Ho;Son, You-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.25 no.1
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    • pp.122-126
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    • 2004
  • Biofunctional nanohybrids are synthesized from layered double hydroxide (LDH) and the vitamins such as ascorbic acid and topopherol acid succinate. Either ion exchange or copricipitaion leads to successful intercalation of the vitamins into gallery space of LDH that offers a new route to safe preservation of bioactivity as well as controlled release. Intercalations of vitamins are clearly reflected on the increase in the basal spacing of ZnAl-(Nitrate) LDH from 8.5 ${\AA}$ to 10.5 ${AA}$ for ascorbate, and 49.0 ${AA}$ for tocopherol acid succinate, respectively. No significant change in UV-Vis and IR absorption characteristics of the intercalated vitamins strongly supports the safe maintenance of their bioactivities without any deterioration of chemical and structural integrity. Furthermore, it is shown that the hybridized vitamins could be discharged in a controlled kinetics.

Fat Cell Formation and Obesity-Related Diseases

  • Kawada, Teruo
    • Preventive Nutrition and Food Science
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    • v.8 no.1
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    • pp.105-112
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    • 2003
  • Animals possess a highly sophisticated mechanism of storing energy in adipose tissue inside their bodies. However, in humans it has been clarified that adipocyte (fat cell), which composes the body fat (adipose) tissues, development and the extent of subsequent fat accumulation are closely associated with the occurrence and advancement of various common diseases (e.g., type-2 diabetes, coronary artery disease, and hypertension) resulting from obesity. Recent exciting progress in clinical and biochemical studies of adipocytes has rapidly clarified the functions of adipocytes and adipose tissue. Interesting findings are the function of white adipocytes as "secreting cells" and the molecular mechanism undelying adipocyte differentiation at the transcriptional level in relation to nuclear receptors. Consequently, the adipose tissue is being targeted for the prevention or treatment of many common diseases. In this review, I will focus on recent information on characteristics of adipocytes and the relationship between obesity and common obesity-related diseases. diseases.

A study on the E-beam resist characteristics of plasma polymerized styrene (플라즈마중합 스티렌 박막의 e-beam 레지스트 특성에 관한 연구)

  • 이덕출;박종관
    • Electrical & Electronic Materials
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    • v.7 no.5
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    • pp.425-429
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    • 1994
  • In this paper, we study on the plasma polymerized styrene as a negative electron-beam resist. Plasma polymerized thin film was prepared using an interelectrode inductively coupled gas-flow type reactor. We show that polymerization parameters of thin film affect sensitivity and etching resistance of the resist. Molecular weight distribution of plasma polymerized styrene is 1.41-3.93, and deposition rates of that are 32-383[.angs./min] with discharge power. Swelling and etching resistance becomes . more improved with increasing discharge power during plasma polymerization. Etch rate by RIE is higher than that by plasma etching.

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Dielectric Relaxation Characteristics of Biology Thin Film (생체박막의 유전완화특성)

  • Song, Jin-Won;Cho, Su-Young;Lee, Kyung-Sup;Sin, Hun-Gyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.107-110
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    • 2003
  • In this paper, We introduced that the method for determing the dielectric relaxation time $\tau$ of floating monolayers on water interface. Displacement current flowing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$of monolayers in the isotropic polar orientational phase is determined using a linear relationship between the monolayer compression speed $\alpha$ and the molecular area Am. here Displacement current gives a peak at A = Am. The dielectric relaxation time $\tau$ of organic monolayers was examined on the basis of the analysis developed here.

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Inhibitory Substances of a Tau-Type Pumpkin Glutathione S-Transferase: Their Existence and Chemical Properties

  • Hossain, Md. Daud;Suzuki, Toshisada;Fujita, Masayuki
    • Journal of Crop Science and Biotechnology
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    • v.10 no.2
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    • pp.117-122
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    • 2007
  • Distributions of physiological inhibitors of a tau-type pumpkin glutathione S-transferase(CmGSTU3) have been investigated in different organs of pumpkin plants, including the onion bulb and water hyacinth root. Inhibitory effects were observed in alcoholic extracts of all plant parts, but the extracts prepared from the roots of either water hyacinth or pumpkin plant showed the highest effect on CmGSTU3 toward 1-chloro-2,4- dinitrobenzene(CDNB). Results of various chromatographies indicated that a number of inhibitory substances were present in the alcoholic extract of each plant organ. Some macromolecules in the plant extracts exhibited inhibitory effects; however, the extracts might contain a large number of unknown low-molecular-weight inhibitory substances. Some of the low-molecular-weight inhibitors in water hyacinth root extract showed characteristics fluoresce under UV light.

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