• Title/Summary/Keyword: Activation Process

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e-Business Software Infrastructure as Social Overhead Capital

  • Kim, Jong-Rak
    • Proceedings of the CALSEC Conference
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    • 2004.02a
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    • pp.164-167
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    • 2004
  • - Ongoing amplification of network infrastructure and activation of e-Business - More and more all kinds of business process are executed in electronic ways -Need to view e-Business software infrastructure as Social Overhead Capital(omitted)

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Post-transcriptional Regulation of NK Cell Activation

  • Kim, Tae-Don;Park, Ju-Yeong;Choi, In-Pyo
    • IMMUNE NETWORK
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    • v.9 no.4
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    • pp.115-121
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    • 2009
  • Natural killer (NK) cells play key roles in innate and adaptive immune defenses. NK cell responses are mediated by two major mechanisms: the direct cytolysis of target cells, and immune regulation by production of various cytokines. Many previous reports show that the complex NK cell activation process requires de novo gene expression regulated at both transcriptional and post-transcriptional levels. Specialized un-translated regions (UTR) of mRNAs are the main mechanisms of post-transcriptional regulation. Analysis of posttranscriptional regulation is needed to clearly understand NK cell biology and, furthermore, harness the power of NK cells for therapeutic aims. This review summarizes the current understanding of mRNA metabolism during NK cell activation, focusing primarily on post-transcriptional regulation.

Preparation and Characterization of Carbon Nanotubes-Based Composite Electrodes for Electric Double Layer Capacitors

  • Seo, Min-Kang;Park, Soo-Jin
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1523-1526
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    • 2012
  • In this work, we prepared activated multi-walled carbon nanotubes/polyacrylonitrile (A-MWCNTs/C) composites by film casting and activation method. Electrochemical properties of the composites were investigated in terms of serving as MWCNTs-based electrode materials for electric double layer capacitors (EDLCs). As a result, the A-MWCNTs/C composites had much higher BET specific surface area, and pore volume, and lower volume ratio of micropores than those of pristine MWCNTs/PAN ones. Furthermore, some functional groups were added on the surface of the A-MWCNTs/C composites. The specific capacitance of the A-MWCNTs/C composites was more than 4.5 times that of the pristine ones at 0.1 V discharging voltage owing to the changes of the structure and surface characteristics of the MWCNTs by activation process.

Effects of Culture Conditions on The Expression of Cyclin B1 Protein during the First Meiotic Maturation in Bovine Immature Oocytes

  • Hwang Seong-Soo;Yoon Jong-Taek
    • Reproductive and Developmental Biology
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    • v.30 no.2
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    • pp.115-118
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    • 2006
  • Cyclin B1 is known to reflect the M-phase promoting factor (MPF), a universal regulator of G2/M-phase transition, activity during the process of oocytes maturation. To investigate whether culture condition affects the maturation rate and the expression of cyclin B1 protein, bovine immature oocytes are stimulated and cultured according to the following protocols: Experiment 1: denuded oocytes (denude) only, COC only, denuded oocytes+granulosa cells (denude+GCs) and COC+GCs; Experiment 2: no-activation (control), 7% ethanol for 5 min and $10{\mu}l/ml$ ionomycin for 5 min at immediately before maturation. The maturation rates of denude and no-activation group were significantly lower in both experiments (P<0.05), respectively. Co-culture or stimulation method in bovine immature oocytes culture increases the cyclin B1 expression significantly in both experiments (P<0.05). Based on these results, culture condition affects the maturation rate and the expression of cyclin B1 protein during the first meiotic maturation in bovine immature oocytes.

A theoretical study on the role of government for the activation of B2B in Korea (국내 기업간 전자상거래 활성화를 위한 정부 역할에 관한 연구)

  • 백종구
    • The Journal of the Korea Contents Association
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    • v.2 no.1
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    • pp.46-51
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    • 2002
  • With the Internet, many enterprises have been able to improve their productivity, gain opportunity to get competitive power and access to potential global customers. The why that the support of government is needed in implementation and activation of EC is that EC is the best way to reduce the transaction cost in business process. This study examines factors affecting the activation of B2B and selects the three sides needed the support of government. With that point, This study proposes a role of government in that three sides.

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Basic Studies on Propellant Casting (II). Effects of Solid Additives on Urethane Polymerization (추진제 성형에 관한 기초연구 (제2보). 우레탄 중합에 미치는 첨가제 효과)

  • Young Gu Cheun;Ik Choon Lee;Shi Choon Kim
    • Journal of the Korean Chemical Society
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    • v.25 no.4
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    • pp.214-218
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    • 1981
  • Kinetic studies were carried out on urethane polymerization reaction of hydroxyl-terminated polybutadiene with isophorone diisocyanate under presence of Hexogen as solid additive. The rate was found to increase with the amount of Hexogen added. However the rate acceleration was not a catalytic effect but solely due to an increase of activation entropy. The reaction was a good 2nd order process with nearly constant activation energy of 8.4 kcal/mole.

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Synthesis of Fe-TiB2 Nanocomposite by a combination of mechanical activation and heat treatment

  • Hyunh, Xuan Khoa;Nguyen, Quoc Tuan;Kim, Ji-Sun;Gang, Tae-Hun;Kim, Jin-Cheon;Gwon, Yeong-Sun
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.91.2-91.2
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    • 2012
  • The TiB2-reinforced iron matrix nanocomposite (Fe-TiB2) was in-situ fabricated from titanium hydride (TiH2) and iron boride (FeB) powders by a simple and cost-effective process that combines the mechanical activation (MA) and a subsequent heat treatment (HT). Effect of milling factors and synthesized temperatures on the formation of the nanocomposite were presented and discussed. A differential thermal analyser (DSC-TG) was employed for examination of thermal behavior of MAed powders. Phases of the nanocomposite were confirmed by X-ray diffraction analysis (XRD). The morphologies and microstructure of nanocomposite were investigated by field emission-scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). Phase composition and distribution were analyzed by electron probe X-ray microanalysis (EPMA). Results showed that TiB2 particles formed in nanoscale were uniformly distributed in alloyed Fe matrix.

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Development of Bio-AC Filter for Heavy Metal Adsorption (중금속 제거에 우수한 바이오 활성탄 필터의 개발)

  • Kim, Hak-Hee;Yoon, Kyung-Sik
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.541-546
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    • 2003
  • Activated carbon was prepared from coffee wastes by chemical activation with $ZnCl_{2}$, NaOH and KOH. The coffee wastes was used as raw material. Preparation process involves the roasting of raw material and carbonization of roasted material followed by chemical activation. N2-BET surface areas of activated coffee char prepared by chemical activation was measured as $1,110{\sim}2,442m^{2}/g$. Removal of copper and chromium in solution by activated carbon was carried out and structural change of pore surface was observed by SEM.

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Silver Activation Process Utilizing Permanganate Oxidation for Electroless Copper Plating on PET (과망간산염의 산화 과정을 응용한 PET 위 무전해 도금의 은 활성화 공정)

  • Lee, Hong-Gi;Heo, Jin-Yeong;Im, Yeong-Saeng;Lee, Geon-Hyeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2015.05a
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    • pp.181-182
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    • 2015
  • 본 실험에서는 PET 위 무전해 도금을 위한 대안 공정 개발을 목적으로 은(Ag)와 과망간산염($MnO_4{^-}$)를 사용하여 기존에 일반적으로 사용된 Sn/Pd의 Sensitization과 Activation process를 대체하는 기술을 연구했다. Palladium(Pd)의 경우 공정비용에서 높은 부분을 차지하기 때문에 이를 대신하여 Ag를 사용했으며, PET 표면의 전처리를 위해 Ultra Violet과 과망간 산염을 이용하여 표면의 친수성을 높였다. 과망간산염을 사용하여 표면을 전처리하는 과정에서 이산화망간($MnO_2$)과 알코올 작용기가 생성되는데 Ag activation 단계에서 촉매 생성에 중간 매개체 역할을 하는 것으로 사료된다. 이와 같은 결론을 도출 하기 위해서 표면 위 Ag의 화학적 구조 및 상 분석을 위해 XPS와 TEM이 사용되었으며 표면에서 Ag는 Ag-O와 같은 Silver oxide의 형태와 Ag-Mn-O와 같은 Compound로 무전해 도금을 위한 촉매 역할 하는 것으로 판단된다.

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