• Title/Summary/Keyword: Self-reaction

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Effects of Thiamine Pyrophosphate on the Inhibition of Self-splicing of Primary Transcripts of T4 phage Thymidylate Synthase Gene in the Presence of GTP

  • Park, In-Kook;Lee, Hyun-Joo;Ahn, Sung-Joon;Sook Shin
    • Journal of Microbiology
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    • v.40 no.2
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    • pp.134-139
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    • 2002
  • Effects of GTP on the inhibition of self-splicing of primary transcripts of the phage T4 thymidylate synthase gene (td) by thiamine pyrophosphate and its analogs have been investigated. The order of the inhibitory efficiency for compounds tested was as follows: thiamine pyrophosphate > thiamine monophosphate > thiamine. of all compounds examined, thiamine pyrophosphate was the most potent inhibitor, Increasing GTP concentration in splicing reaction tended to overcome the suppressive effects of self-splicing by thiamine pyrophosphate and its analogs. The inhibition by thiamine pyrophosphate was most sensitized to a higher concentration of GTP, It has been speculated that the key structural features in thiamine pyrophosphate and its analogs responsible for the inhibition of splicing may be a thiamine moiety in which the phosphorylation of 2-hydroxylethyl group on 5-position of thiazolium ring rendered further stimulation of inhibition in self-splicing reaction..

Plugging and Re-opening Phenomena of the 5Cr-1Mo Steel Leak Hole by Water Leakage in Sodium Atmosphere (소듐 분위기에서 물누출에 의한 5Cr-1Mo Ferrite강 구멍의 막힘과 재개방 현상)

  • Jeong, Kyung-Chai;Kim, Tae-Joon;Choi, Jong-Hyeun;Park, Jin-Ho;Hwang, Sung-Tai
    • Applied Chemistry for Engineering
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    • v.9 no.5
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    • pp.674-679
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    • 1998
  • Small water leak experiment was carried out in liquid sodium atmosphere using a specimen of ferrite steel, which will be expected to be a material of the heat transfer tube of liquid metal fast breeder reactor. Self-plugging phenomena of leak path could be explained by the products of reaction and corrosion by sodium-water reaction. Also, re-opening mechanism of self-plugged path could be explained by the thermal transient and vibration of heat transfer tube. As a result, perfect re-opening time of self-plugged leak path was observed to be 129 minutes after water leak initiation. Re-opening shape of a specimen was appeared with double layer of circular type, and re-opening size of this specimen surface was about 2 mm diameter on sodium side.

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The Effects of Instructor's Non-verbal Communication on High School Student Athletes' Emotional Reaction and Self-efficacy (지도자의 비언어적 커뮤니케이션이 체육고등학교 학생운동선수들의 감정반응과 자기효능감에 미치는 영향)

  • Park, Young-Chan;Ko, Wi-Sug
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.170-185
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    • 2016
  • The purpose of this study was to investigate the relationship among instructor's non-verbal communication, emotional reaction, and self-efficacy. By using convenience sampling method of non-provability sampling, 258 student athletes from S and D cities were selected for a questionnaire survey. The 184 returned surveys were analyzed with structural equation modeling through SPSS 22.0 and AMOS 22.0 statics program. The study results are summarized as follows. First, instructor's non-verbal communication has a positive influence on emotional reaction of high school student athletes. Second, high school student athletes experiencing emotional reactions by instructor have a positive influence on self-efficacy. Third, instructor's non-verbal communication does not influence self-efficacy of high school student athletes directly. Fourth, emotional reactions of high school student athletes experienced by instructor's non-verbal communication have a mediating effect on self-efficacy. Fifth, neither gender nor exercise period has a moderating effect on the relationship between non-verbal communication, emotional reactions, and self-efficacy.

Polymerization Behavior of Self-healing Agents for Damage Repair in Composite Materials (복합재 손상보수용 자가치료제의 중합 거동)

  • Oh, Jinoh;Yoon, Sungho;Jang, Seyong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.18 no.5
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    • pp.35-42
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    • 2014
  • Thermal analysis properties and adhesive properties of self-healing agents were evaluated through differential scanning calorimetry, reaction heat measurement, and adhesive shear test. D1E0, D3E1, D1E1, D1E3, and D0E1, depending on the mixing ratio of DCPD and ENB, were considered as self-healing agents. The amount of Grubbs' catalyst, depending on the type of self-healing agents, was varied from 0.1 wt% to 1.5 wt%. In the case of DCPD, the polymerization reaction occurred faster and the stabilized adhesive strength increased as the amount of catalyst increased; however, a large amount of catalyst was required. ENB had excellent reactivity with a small amount of the catalyst; however, high reaction heat was observed at the early stage of polymerization. Thermal analysis properties and adhesive properties of self-healing agents can be controlled by varying a mixing ratio of DCPD and ENB. Among the self-healing agents used for this study, the D3E1 would be one of the most preferable candidates with regard to maximum adhesive strength, reaching time to maximum adhesive strength, stabilized adhesive strength, and reaction heat.

Neutron Diffraction Study of Powders Prepared by Self-propagating High Temperature Synthesis

  • Park, Yong;Kim, Y S.;Y. D. Hahn;S. H. Shim;Lee, J. S.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2000.11a
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    • pp.11-12
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    • 2000
  • Non-stoichiometric ceramics of $Ni_{x}ZnO_{1-x}Fe_{2}O_{4}$ were prepared by self-propagating high temperature synthesis reaction with various processing conditions and their stoichometric numbers were determined by neutron diffraction. The neutron diffraction patterns were measured at room temperature using monochromatic neutrons with a wave length of 0.18339 nm from a Ge(331) mocochromator at a 90 degree take off angle. The Rietveld refinement of each pattern converged to good agreement (x2=1.88-2.24). The neutron diffraction analysis revealed the final stoichiometries of the ferrites were $Ni_{0.38}Zn_{0.62}Fe_{2}O_{4}$ and $Ni_{0.33}Zn_{0.67}Fe_{2}O_{4]$, respectively. This supports that final stoichiometric number of the self-propagating high temperature synthesis product can be controlled by the processing parameters during the combustion reaction.

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New Self-Directed Growth Mechanism of Molecular Lines across the Dimer Rows on H-terminated Si(001) Surface

  • Choi, Jin-Ho;Cho, Jun-Hyung
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.301-301
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    • 2011
  • We present theoretical investigations of the self-assembled growth of one-dimensional (1D) molecular lines directed across the dimer rows on the H-terminated Si(001) surface [1]. Based on density-functional theory calculations, a new growth mechanism of the 1D acetylacetone line is proposed [2], which involves the radical chain reaction initiated at two dangling-bond sites on one side of two adjacent Si dimers. It is also enabled that, if an H-free Si dimer were employed as the initial reaction site, a 1D acetylacetone line can grow along the dimer row. Our findings represent the first insight into the growth of 1D molecular lines not only across but also along the dimer rows on the H-terminated Si(001) surface.

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Detector Foil Self-Shielding Correction Factors

  • Kwon, Oh-Sun;Kim, Bong-Ghi;Suk, Ho-Chun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05a
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    • pp.197-201
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    • 1996
  • In the detail reaction-rate measurements in a critical assembly using the foil activation method, the measured activations of detector foils have inevitably errors caused by detector foil self-shielding effect. If neutron flux could be approximated to Westcott flux: i.e. well thermalized Maxwellian distribution, these activations of detector foil could be corrected to represent the unperturbated flux at any detected position in the cell with using Westcott option and reaction-rate option of the lattice code, WIMS-AECL. These calculated detector material self-shielding correction factors of the tested fuel, CANFLEX provided much information about neutron spectrum of test lattice cell as well as the correction factors themselves. The results could be verified by another lattice calculations.

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Redox-Active Self-Assembled Monolayer on Au ultramicroelectrode and its Electrocatalytic Detection of p-aminophenol Oxidation

  • Kim, Yun Jee;Kim, Ki Jun;Jung, Seung Yeon;Hwang, You Jin;Kwon, Seong Jung
    • Journal of Electrochemical Science and Technology
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    • v.10 no.2
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    • pp.170-176
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    • 2019
  • Alkanethiol self-assembled monolayers (SAMs) and partially ferrocene (Fc) modifications were applied to the Au ultramicroelectrode (UME) rather than to standard sized electrodes with dimension of millimeters. The electron transfer mediation of the SAMs and Fc modified Au UME was investigated by using a p-aminophenol (p-AP) oxidation reaction via cyclic voltammetry. The electrocatalytic p-AP oxidation at the SAMs and Fc modified Au UME showed a much larger electrocatalytic current density than that at the standard sized electrode due to the fast mass transfer rate at the UME.

Studies on the Kinetics for the Formation Reaction $Ti_3AI$ by SHS (Self-propagating High-temperatuer Synthesis) Method (자체반응열 고온합성법에 의한 $Ti_3AI$ 생상반응의 동력학적 연구)

  • 전광식
    • Journal of the Korean Ceramic Society
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    • v.35 no.6
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    • pp.569-574
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    • 1998
  • The thickness of flame zone reaction rate and apparent activation energy in the formation reaction of $Ti_3AI$ intermetallic compound were investigated using SHS method which sustains the reaction spontaneously and utilizes the heat generated by thye exothermic reaction itself. In this reaction the thickness of flame zone was 1.4 mm and the reaction rate was $0.4g/\textrm{cm}^2{\cdot}sec$. Also the apparent activation energy calculated using from the experimental data obtained by controlling the realtive green density was 40kJ/mol.

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