• Title/Summary/Keyword: Surface activation

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Regulation of Immune Responses by the Activating and Inhibitory Myeloid-Associate Immunoglobuline-Like Receptors (MAIR) (CD300)

  • Shibuya, Akira;Nakahashi-Oda, Chigusa;Tahara-Hanaoka, Satoko
    • IMMUNE NETWORK
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    • v.9 no.2
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    • pp.41-45
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    • 2009
  • Activating and inhibitory cell surface receptors play important roles in regulation of immune responses. Recent progress has demonstrated that many inhibitory receptors pair with activating, as well as inhibitory, isoforms, both of whose genes are located in small clusters on a chromosome. We and others identified paired activating and inhibitory immunoglobulin-like receptors, designated myeloid-associated immunoglobulin-like receptors (MAIR) (CD300). MAIR is a multigene family consisting of nine genes on a small segment of mouse chromosome 11. MAIR family receptors are preferentially expressed on myeloid cells, including macrophages, dendritic cells, granulocytes, and bone-marrow-derived cultured mast cells, and a subset of B cells and regulate activation of these cells. Thus, MAIR plays an important role in innate immunity mediated by myeloid cells.

Electrochemical Properties of EDLC Electrodes Prepared by Acid and Heat Treatment of Commercial Activated Carbons

  • Wu, Jin-Gyu;Hong, Ik-Pyo;Park, Sei-Min;Lee, Seong-Young;Kim, Myung-Soo
    • Carbon letters
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    • v.9 no.2
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    • pp.137-144
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    • 2008
  • The commercial activated carbons are typically prepared by activation from coconut shell char or coal char containing lots of inorganic impurities. They also have pore structure and pore size distribution depending on nanostructure of precursor materials. In this study, two types of commercial activated carbons were applied for EDLC electrode by removing impurities with acid treatments, and controlling pore size distribution and contents of functional group with heat treatment. The effect of the surface functional groups on electrochemical performance of the activated carbon electrodes was investigated. The initial gravimetric and volumetric capacitance of coconut based activated carbon electrode which was acid treated by $HNO_3$ and then heat treated at $800^{\circ}C$ were 90 F/g and 42 F/cc respectively showing 94% of charge-discharge efficiency. Such a good electrochemical performance can be possibly applied to the medium capacitance of EDLC.

Adsorptive removal of odour substances and NO and catalytic esterification using empty fruit bunch derived biochar

  • Lee, Hyung Won;Kim, Jae-Kon;Park, Young-Kwon
    • Carbon letters
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    • v.28
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    • pp.81-86
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    • 2018
  • Empty fruit bunch (EFB) char was used to remove $NO_x$ and odorous substances. The physicochemical properties of the EFB chars were altered by steam or KOH treatments. The Brunauer-Emmett-Teller surface area and porosity were measured to determine the properties of the modified EFB chars. The $deNO_x$ and adsorption test for hydrogen sulphide and acetaldehyde were performed to determine the feasibility of the modified EFB chars. The KOH-treated EFB (KEFB) char revealed higher $deNO_x$ efficiency than with commercial activated carbon. The Cu-impregnated EFB char also had high $deNO_x$ efficiency at temperatures higher than $150^{\circ}C$. The KEFB char showed the highest hydrogen sulphide and acetaldehyde adsorption ability, followed by the steam-treated EFB char and untreated EFB char. Moreover, the product prepared by sulfonation of EFB char showed excellent performance for esterification of palm fatty acid distillate for biodiesel production.

Preparation and Electric Double Layer Capacitance of Mesoporous Carbon

  • Shiraishi, Soshi;Kurihara, Hideyuki;Oya, Asao
    • Carbon letters
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    • v.1 no.3_4
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    • pp.133-137
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    • 2001
  • Mesoporous activated carbon fiber (ACF) was prepared from phenolic resin containing a small amount (0.1 wt %) of organic nickel complex through carbonization and steam activation. Microporous ACF as reference sample was also prepared from phenolic resin without agent. In both cases of the mesoporous ACFs and the microporous ACFs, the electric double layer capacitance of the nonaqueous electrolyte (0.5 M $TEABF_4$/PC or 1.0 M $LiClO_4$/PC) was not proportional to the BET specific surface area. This is owing to the low permeability of nonaqueous electrolyte or the low mobility of ion in narrow micropores. However, the mesoporous ACF showed higher double layer capacitance than the microporous (normal) ACF. This result suggests that the presence of many mesopores promotes the formation of effective double layer or the transfer of ion in the micropore.

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Preparation of Composite Adsorbents by Activation of Water Plant Sludge and Phenolic Resin Mixtures

  • Myung, Heung-Sik;Kim, Dong-Pyo
    • Carbon letters
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    • v.1 no.3_4
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    • pp.154-157
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    • 2001
  • Composite adsorbents were prepared by mixing water plant sludge with phenolic resin having the ratio of 1 : 1, 1 : 2, and 1 : 3 respectively, curing from $100^{\circ}C$ to $170^{\circ}C$ under $N_2$ atmosphere, and then activating with $N_2$ at $700^{\circ}C$. Thermal property, specific surface area and morphology of the composite adsorbents as well as their precursors were measured by TGA, BET and SEM respectively. Removal efficiency of the composite adsorbents to ${NH_4}^+$ and TOC was compared with those of commercial zeolite and activated carbon. The adsorbents presented very promising TOC removal efficiency of 98%, which was identical level to that of commercial activated carbon while they displayed removal efficiency, only 32%, of ${NH_4}^+$. Therefore, this composite adsorbent considered as the alternative material of commercial activated carbon, used as an expensive removal agent of organic substances and THM in water treatment plant and it also suggested a possibility of practical application in other processes.

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Activation of Spinel Phase Magnetite by Hydrogen Reduction (스피넬상 마그네타이트의 수소환원에 의한 활성화)

  • 류대선;이동석;이풍헌;김순태
    • Journal of the Korean Ceramic Society
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    • v.37 no.6
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    • pp.559-563
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    • 2000
  • To decompose carbon dioxide, magnetite was synthesized with 0.2M-FeSO4$.$7H2O and 0.5 M-NaOH by coprecipitation. The deoxidized magnetite was prepared from the magnetite by hydrogen reduction for 1, 1.5, 2 hr. The degree of hydrogen reduction and the decomposition rate of carbon dioxide were investigated with hydrogen reduction time. The crystal structure of the magnetite was identified spinel structute by the X-ray powder diffractions. After magnetite was reduced by hydrogen, magnetite reduced by hydrogen become new phae(${\alpha}$-Fe2O3, ${\alpha}$-Fe) and spinel type simultaneously. After decomposing of carbon dioxide at 350$^{\circ}C$, new phse(${\alpha}$-Fe2O3, ${\alpha}$-Fe) were removed and the spinel type only existed. The specific surface area of the synthesized magnetite was 46.69㎡/g. With the increase of the hydrogen reduction time, the grain size, the hydrogen reduction degree and the decomposition rate of carbon dioxide was increased.

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Impact of Passivation and Reliability for Base-exposed InGaP/GaAs HBTs

  • Park, Jae-Woo
    • Transactions on Electrical and Electronic Materials
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    • v.8 no.3
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    • pp.115-120
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    • 2007
  • Reliability between passivated and unpassivated process with the base-exposed InGaP/GaAs HBTs was studied. A passivation of HBT was attempted by $SiO_2$ thin film deposition at $300^{\circ}C$ by means of PECVD. Base-exposed InGaP/GaAs HBTs before and after passivation were investigated and compared in terms of DC and RF performance. Over a total period of 30 days, passivated HBTs show only 2% degradation of DC current gain for the high current density of $40KA/cm^2$. The measured thermal resistance of $2{\times}30{\mu}m^2$ single emitter InGaP/GaAs HBT passivated with PECVD $SiO_2$ devices can be extracted and was founded to be 1430 K/W. The estimated MTTF was $2{\times}10^7hr\;at\;T_j=125^{\circ}C$ with an activation energy $(E_a)$ of 1.37 eV.

The Effect of Nonionic Interface Activation Substances in Reduction Phenomenon of Streaming electrification (유동대전 감소현상에 미치는 비이온성 계면활성제의 효과)

  • Kim, Y.W.;Chung, K.H.;Yoo, K.M.;Yoo, J.H.;Lee, E.H.;Lee, D.C.
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1410-1412
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    • 1998
  • The purpose of this study is to find the way to prevent the electrostatics from the interface of liquid and solid by adding interface active substances to the insulating oil with concentration. As results, The streaming current, surface tension, and viscosity decreased and conductivity increased at the higher point than the c.m.c. which resulted from, the adding of the interface active substances.

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A Study on the Surface Activation and Quick-setting Characteristics of Blast Furnace Slag (Blast furnace slag의 표면 활성화 특성 및 quick-setting 특성에 관한 연구)

  • Lee, Woong-Geol;Song, Yung-Sin;Kang, Hyun-Ju;Choi, Hun;Song, Yong-Jin
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.273-274
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    • 2010
  • This study investigated on the early hydration and physical characteristics of blast furnace slag through pH variation. The pH values applied to the experiments were, 12.0 and 13.0 which are the pH values of OPC, and type 3 of pH 14.0 which is a strong alkali condition. A paste and mortar method was used to test blast furnace slag and blast furnace slag containing 2wt% of gypsum. It was found that CAH and CSH phases were formed as key hydrates during the early hydration of blast furnace slag, and ettringites were produced extra during the early hydration of blast furnace slag containing 2wt% of gypsum.

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Excimer Laser-Assisted In Situ Phosphorus Doped $Si_{(1-x)}Ge_x$ Epilayer Activation

  • Bae, Ji-Cheul;Lee, Young-Jae
    • ETRI Journal
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    • v.25 no.4
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    • pp.247-252
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    • 2003
  • This paper presents results from experiments on laser-annealed SiGe-selective epitaxial growth (LA-SiGe-SEG). The SiGe-SEG technology is attractive for devices that require a low band gap and high mobility. However, it is difficult to make such devices because the SiGe and the highly doped region in the SiGe layer limit the thermal budget. This results in leakage and transient enhanced diffusion. To solve these problems, we grew in situ doped SiGe SEG film and annealed it on an XMR5121 high power XeCl excimer laser system. We successfully demonstrated this LA-SiGe-SEG technique with highly doped Ge and an ultra shallow junction on p-type Si (100). Analyzing the doping profiles of phosphorus, Ge compositions, surface morphology, and electric characteristics, we confirmed that the LA-SiGe-SEG technology is suitable for fabricating high-speed, low-power devices.

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