• Title/Summary/Keyword: basic research

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Alq$_3$-based organic light-emitting devices with Al/fluoride cathode; Performance enhancement and interface electronic structures

  • Park, Y.;Lee, J.;Kim, D.Y.;Chu, H.Y.;Lee, H.;Do, L.M.;Zyung, T.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.105-107
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    • 2002
  • The device characteristics and the interface electronic structures of organic light-emitting devices based on tris-(8-hydroxyquinoline)aluminum were investigated with $Al/CaF_2$, Al/LiF, and Al-only cathodes. Similar to the Al/LiF cathode, the $Al/CaF_2$ cathode greatly improved the performance of the device over Al-only cathode. However, a photoelectron spectroscopy study revealed that despite the performance improvement, the evolution of the new peaks during $Al/CaF_2$ cathode formation closely resembled those of the Al-only cathode rather than the Al/LiF cathode.

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Determination of Zinc in the Scalp Hair of the Reumatoid Arthritis Patients (관절성 루머티스 환자의 머리카락 중 아연의 분석)

  • Kim, Jung Ae;Park, Sang Min;Lee, Won;Choi, Beom Suk
    • Analytical Science and Technology
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    • v.8 no.1
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    • pp.101-105
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    • 1995
  • The concentration of zinc of the Reumatoid Arthritis patients has been determined by ICP-AES, and the analytical results are discussed. It is observed that the zinc concentration is largely affected by the length of scalp hair. The concentrations of zinc in the distal end are much higher than that of the proximal end.

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Preparation of Vesicles Using Octasubstituted Cyclotetraphosphazene (Octasubstituted Cyclotetraphosphazene으로부터 Vesicle의 형성)

  • Shin, Young Jae;Park, Chul Soon;Kim, Ju Youn;Kim, Se Ra;Shin, Jae Sup
    • Applied Chemistry for Engineering
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    • v.18 no.1
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    • pp.54-57
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    • 2007
  • A cyclotetraphosphazene derivative having eight chains was synthesized from octachlorocyclotetraphosphazene, which was employed along with cholesterol for the preparation of vesicles. The resulting vesicles were characterized by TEM and encapsulation efficiency. The stability of the vesicles was enhanced in the presence of dihexadecylphosphate.

Polarized Light Scattering Spectroscopy for Particle Size Measurement on Surface (편광산란분광법을 이용한 표면의 입자 크기 측정)

  • Cho, Hyoung-Jun;Choi, Chi-Kyu;Kim, Doo-Chol;Yu, Young-Hun
    • Korean Journal of Optics and Photonics
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    • v.16 no.6
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    • pp.560-564
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    • 2005
  • We used the polarized light scattering spectroscopy(PLSS) to get selectively the particle size information on a surface in optically diffuse material, and we analyzed the experimental results by Mie scattering theory. We found that the PLSS was the proper method fer getting the surface information in optically diffuse material. This method is able to be used in biotechlology area for diagnostics.

Feasibility Study for the Monitoring of Urea in Dialysate Solution using Raman Spectroscopy

  • Kim, Jae-Jin;Hwang, Jin-Young;Kim, Yong-Dan;Chung, Ho-Eil
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.805-808
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    • 2011
  • We have determined the urea concentration in an aqueous solution using Raman spectroscopy by incorporating a Teflon tube as an effective intensity correction standard as well as sample container. A non-overlapping Teflon band was used as the reference peak to correct Raman intensity variations that occasionally resulted from changes in laser power. To increase the sensitivity, we positioned a copper reflector inside the Teflon tube to maximize the collection of Raman scattering. The obtained accuracy using Raman spectroscopy was 0.53 mM, close to the range of accuracy of previous NIR studies (0.15-0.52 mM).

Comparison of Enantioselective CEC Separation of OT-MIP Capillary Columns with Templates of Various Camphor Derivatives Made by the Pre-established General Preparation Protocol

  • Zaidi, Shabi Abbas;Lee, Seung-Mi;Lee, Ju-Young;Cheong, Won-Jo
    • Bulletin of the Korean Chemical Society
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    • v.31 no.10
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    • pp.2934-2938
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    • 2010
  • Some open tubular (OT) molecule imprinted polymer (MIP) silica capillary columns with templates of camphor derivatives such as 10-camphorsulfonic acid (10-CSA), 10-camphorsulfonamide (10-CS) and camphor-p-tosyl hydrazone (CTH) have been successfully prepared by the prior generalized preparation protocol. The three MIP thin layers of different templates showed quite different morphologies. The chiral selectivity of each MIP column for the template enantiomers was optimized by changing eluent composition and pH. The optimization conditions were found to be different for the three MIPs. This work suggests prospective successful extension of the generalized preparation protocol for OT-MIP silica capillary columns toward templates of a variety of chemical groups.

Single Organic Molecules Designed as Nanoscale Connectors: Fullerene Isoxazoline Derivatives

  • Lee, Han-Myong;Lee, Chang-Hoon;Cho, Min-Sil;Hwang, Yong-Gyoo;Lee, Kee-Hag
    • Bulletin of the Korean Chemical Society
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    • v.25 no.12
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    • pp.1850-1854
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    • 2004
  • Recently a fullerene isoxazoline was reported as an example for nanoscale connectors in molecular electronic devices. The construction of nanoscale devices is a potentially important area of technology. By using the semiempirical PM3 calculation, we optimized the structures for two fullerene isoxazoline derivatives and thirteen regioisomers of the second addition of a nitride oxide to a fullerene isoxazoline derivative. Our results suggest that fullerene isoxazoline derivatives could be used as nanoscale connectors with the possibility of attaching of spacer units in a specific angle arrangement.

Adenosine Inhibits ATP-induced Calcium Influx in PC12 Cells

  • Park, Tae-Ju;Park, Se-Young;Song, Sook-Keun;Kim, Kyong-Tai
    • Proceedings of the Korean Biophysical Society Conference
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    • 1997.07a
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    • pp.32-32
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    • 1997
  • The regulatory role of A$\sub$2A/ adenosine receptors in P$_2$ purinoceptor-mediated calcium signaling was investigated in rat pheochromocytoma (PC12) cells. When PC12 cells were treated with 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine (CGS21680), a specific agonist of the A$\sub$2A/ adenosine receptor, extracellular ATP-evoked [(CA$\^$2+/)]$\sub$i/ rise was inhibited by 20%.(omitted)

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Serum Proteomic Analysis of Scrub Typhus Patients for Screening Antigenic Proteins Originating from Orientia tsutsugamushi

  • Lee, Sang-Yeop;Yun, Sung Ho;Bang, Geul;Lee, Chang-Seop;Kim, Seung Il
    • Mass Spectrometry Letters
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    • v.12 no.3
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    • pp.76-80
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    • 2021
  • Scrub typhus is an acute febrile disease caused by the pathogenic bacterium Orientia tsutsugamushi, belonging to the Rickettsiaceae family. The shotgun proteomic analysis was performed using the sera of scrub typhus patients to identify the proteins having their origin in O. tsutsugamushi. Three different databases approaches were used for the identification of the proteomes. We identified the RsmD, an RNA methyltransferase as the commonly detected protein from all three approaches. This protein was not detected in the sera of healthy negative controls. We believe that this protein is a potential biomarker of Orientia tsutsugamushi present in the sera of scrub typhus patients.