• Title/Summary/Keyword: Blue phase

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Characteristics of Protein Chromatography by Affinity Membrane Mudule (친화성 막모듈에 의한 단백질 크로마토그래픽 특성)

  • 이광진;염경호
    • KSBB Journal
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    • v.13 no.2
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    • pp.125-132
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    • 1998
  • Protein affinity membrane was prepared via the coating of chitosan gel on the porous flat polysulfone membrane surface, followed by the immobilization f the reactive dye (Cibacron Blue 3GA) to the chitonsan gel. The maximum protein binding capacity of affinity membrane was about 70${\mu}g/cm^2$ determined by the batch adsorption experiments of human serum albumin (HSA). Using module of this membrane, the characteristics of protein chromatography were investigated through the experiments of elution and frontal chromatography of HSA. This membrane module promises as a chromatography column, since it represented a lower pressure drop and a greater reproducibility. The protein separation ratio was significantly influenced by the flow rate of mobile phase and the injection quantity of HSA. The dynamic protein binding capacity of module decreased from the equilibrium binding capacity with increasing flow rate and approached the value of 15 - 20 ${\mu}g/cm^2$ for flow rates above 6 mL/min.

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Effect of True Partition Coefficient on the Determination of Extraction Coefficient of Ion-Pair Complexes (이온대 화합물의 참분배계수가 축출정수 결정에 미치는 영향)

  • 심창구
    • YAKHAK HOEJI
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    • v.27 no.2
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    • pp.125-131
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    • 1983
  • Whether ($AB_{w}$) may be neglected against ($A_{w}^{+}$) in the calculation of the extraction coefficient of ion-pairs was criticized by both experiments and theoretical consideration, where ($AB_{w}$) and ($A_{w}^{+}$) mean the molar concentration of ion-pair AB and cation $A^{+}$ in the aqueous phase. Ion-pair complexes were partitioned between phosphate buffer (pH 7.4) and n-octanol. Tetrabutylammonium, isopropamide and methylene blue were selected as cations and benzoic acid, p-toluenesulfonic acid, salicylic acid and taurodeoxycholic acid were selected as counter ions (anions). As a result, conventional methods which assume no existence of ($AB_{w}$) were proven to lack generality. The equation proposed in my earlier report was confirmed to be valid as a general method.

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A Convenient Method to Prepare Ag Deposited N-TiO2 Composite Nanoparticles via NH3 Plasma Treatment

  • Hu, Shaozheng;Li, Fayun;Fan, Zhiping
    • Bulletin of the Korean Chemical Society
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    • v.33 no.7
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    • pp.2309-2314
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    • 2012
  • Ag deposited N-$TiO_2$ composite nanoparticles were prepared via $NH_3$ plasma treatment. X-ray diffraction, UV-vis spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy were used to characterize the prepared $TiO_2$ samples. The plasma treatment did not change the phase composition and particle sizes of $TiO_2$ samples, but extended its absorption edges to the visible light region. The photocatalytic activities were tested in the degradation of an aqueous solution of a reactive dyestuff, methylene blue, under visible light. The photocatalytic activities of Ag deposited N-$TiO_2$ composite nanoparticles were much higher than Ag-$TiO_2$, N-$TiO_2$, and P25. A possible mechanism for the photocatalysis was proposed.

Enhanced Visible Light Activity and Stability of TiO2 Nanopowder by co-doped with Mo and N

  • Hu, Shaozheng;Li, Fayun;Fan, Zhiping
    • Bulletin of the Korean Chemical Society
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    • v.33 no.4
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    • pp.1269-1274
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    • 2012
  • A visible light responsive N, Mo co-doped $TiO_2$ were prepared by sol-gel method. X-ray diffraction, TEM, $N_2$ adsorption, UV-vis spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy were used to characterize the prepared $TiO_2$ samples. Doping restrained the phase transformation from anatase to rutile and reduced the particle sizes. The band gap was much narrowed after N, Mo co-doping. The photocatalytic activities were tested in the degradation of an aqueous solution of a reactive dyestuff, methylene blue, under visible light. The photocatalytic activities of doped $TiO_2$ were much higher than that of neat $TiO_2$. The photocatalytic stability of N, Mo co-doped $TiO_2$ was much better than that of N doped $TiO_2$.

MULTI-WAVELENGTH FIBRIL DYNAMICS AND OSCILLATIONS ABOVE SUNSPOT WAVE PROPAGATION

  • MUMPUNI, EMANUEL S.;HERDIWIJAYA, DHANI;DJAMAL, MITRA;DJAMALUDDIN, THOMAS
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.59-60
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    • 2015
  • High resolution, multi-wavelength images from the Dutch Open Telescope were used to study the detailed mechanisms that might be involved in the multiple layer solar atmosphere observed in high cadence multi-wavelength observations. With the exceptional data observed for active region NOAA 10789 on 2005 July 13th, we study the changing pattern of the fibril using multi-wavelength tomography of the $H{\alpha}$ line center and blue wing, Ca II H, and the G Band. It is believed that a long fibril that is rooted in the umbra, with longer apparent periodicity, may be due to morphological changes. To determine this, we conduct phase difference and coherency analysis between points along the fibril to understand how the wave propagates.

The Adsorption of Methanethiol and Benzenethiol on Silver Surfaces

  • Lee, Gyeong Hun;Park, Sang Hyeon;Kim, Ho Jing
    • Bulletin of the Korean Chemical Society
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    • v.16 no.2
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    • pp.89-95
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    • 1995
  • The adsorption of methanethiol and benzenethiol on Ag(111) and Ag(100) surfaces is studied respectively, employing ASED (Atom Superposition and Electron Delocalization) method. Metal surfaces are modelled by 3-layer clusters. The corresponding thiolate anions are taken as adsorbates. The highly coordinated binding sites are most favored for both surfaces. The tilted angles of C-S axis from the surface normal are nearly zero. There's Charge transfer from adsorbate to substrate and the stretching frequency of C-S bond upon adsorption is blue-shifted from its gas phase counterpart, and its amount is the smallest at most highly coordinated site. FMO (Fragment Molecular Orbital) analysis of the system give the explanation for these results.

A True Cholesteric Columnar Liquid Crystal

  • Cho, I-Whan;Lim, Young-Soo
    • Bulletin of the Korean Chemical Society
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    • v.9 no.2
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    • pp.98-101
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    • 1988
  • A pure columnar cholesterogen based on the octasubstituted phthalocyanine $(PcH_2)$, S-(+)-2, 3, 9, 10, 16, 17, 23, 24-octakis[5-(dodecyloxy)-2-oxa-pentyl]-phthalocy anine(1a), is described. To evaluate a cholesteric character of 1a, the corresponding achiral $PcH_2$ 1b and the copper complex of chiral $PcH_2$ 1a (CuPc), S-(+)-2,3,9,10,16,17,23,24-octakis[4-(dodecyloxy)- 2-oxapentyl]-phthalocyanine(2a) were also prepared. The chiral 1a exhibited a typical cholesteric texture change in which the transition of platelet (blue phase) to fan-shape texture was observed (K-M-I), whereas the corresponding achiral 1b showed only a focal conic texture (K- M-I). This is the first instance of a pure columnar cholesterogen observed with discotic liquid crystal systems.

Effects of Compound-A on the Early-Phase Anaphylactic Type Hypersensitivity

  • Lee, Ji-Yun;Lee, Jin-Hee;Kim, Tae-Doo;Sim, Sang-Soo;Kim, Chang-Jong
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.125.3-126
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    • 2003
  • Effect of Compound-A, a phenylpropanoid isolated from Arctium lappa fruit, on heterologous passive cutaneous anaphylaxis (HPCA), the release of histamine, and Phospholipase $A_2$ (PLA2) and phosphadiesterase (PDE) activities were studied by the method of Levine and Vaz. Anti-serum was prepared from ovalbumin (OA)-sensitized male Balb/c mouse at two weeks after the last challenge of OA and alumina gel. Heterologous PCA test in rats were carried out to determine the contents of leakaged pigment in the dorsal skin 30 minutes after i.v. injection of 0.2 ml of 1 % OA and 1 % Evans blue mixture (1:1). (omitted)

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Discovery of the prominent radio relics in the cluster merger ZwCL J1447+2619

  • Lee, Wonki;Kim, Hyeonghan;Jee, Myungkook James
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.39.2-39.2
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    • 2019
  • Diffuse radio emissions at the outskirt of merging galaxy clusters called radio relics provide a unique channel to understand the merger history. We present a recent discovery of double radio relics in the cluster merger ZwCL1447+2619 from our recent Giant Metrewave Radio Telescope observations. Both Band 3 (300-500 MHz) and Band 4 (550-850 MHz) data reveal a large (~1Mpc) and thin (~40kpc) radio relic ~1Mpc from the cluster X-ray center and a small radio relic (~0.3 Mpc) on the opposite side. These remarkable radio data together with Subaru weak-lensing analysis and Chandra X-ray observations enable us to reconstruct the merger scenario. Our preliminary analysis suggests that the cluster ZwCL J1447+2619 is a post-merger near its returning phase. In addition, using Keck DEIMOS spectroscopy, we find many "green" and "blue" member galaxies are located between the radio relics, a possible indication of merger shock-driven star formation activities.

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Study on Fluid Inclusions in Fluorite from the Sinpo Mine (신포광산(新浦鑛山) 형석(螢石)의 유체포유물(流體包有物에)에 관(關)한 연구(硏究))

  • Lee, Choon Woo
    • Economic and Environmental Geology
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    • v.2 no.4
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    • pp.1-21
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    • 1969
  • The Sin po fluorite deposit is of a fissure vein type which strikes $N75^{\circ}E$, dips $80^{\circ}SE$, and is embedded in the pre-Cambrian crystalline schist. The vein is 1 meter in average in thickness, about 800 meters in length and nearly 400 meters in depth. Narrow veins of crustified fluorites and agatic quartz are discontinuously embedded in the quartz gangue. Two-phase fluid inclusions, which are available for the homogenization method by using the Heating Stage Microscope 350, are found in the fluorite crystals. Most of the fluid inclusions are primary in origin and mainly composed of liquid phase associated with minor gas phase. They are tetrahedral, rounded-tubular, wedge shaped, rectangulartrapezoid, and irregular in shape. The maximum diameter of inclusions is 0.5mm and the minimum, 0.03mm, ranging from 0.2mm to 0.08mm in an average. The homogenization temperatures obtained from the test are $135-147^{\circ}C$, $125-138^{\circ}C$, $121-137^{\circ}C$, $116-133^{\circ}C$ and $106-128^{\circ}C$ in greenish, bluish, violet, light grayish blue, colorless and pinkish fluorites respectively. The range of formation temperatures of fluorites is $106-147^{\circ}C$. Therefore, the fluorite deposit of Sinpo Mine is considered to be of low temperature hydrothermal origin. The isothermal lines were drawn on the longitudinal section of the vein from the data of homogenization test. According to the results, the central and lower parts of the ore shoot in the west ore body show the higher temperatures of $130-138^{\circ}C$ and the peripheral and upper parts of it show the lower temperatures of $108-128^{\circ}C$. It seems that the isothermal trend roughly coinside with the pitch of the ore shoot.

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