• Title/Summary/Keyword: Kim Yongtaek

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Synthesis of Soluble Copolyimides Using an Alicyclic Dianhydride and Their $CO_2/CH_4$ Separation Properties (지환족 다이안하이드라이드를 이용한 용해성 폴리이미드 공중합체 합성 및 메탄/이산화탄소 분리특성)

  • Park, Chae Young;Lee, Yongtaek;Kim, Jeong Hoon
    • Membrane Journal
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    • v.24 no.1
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    • pp.1-9
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    • 2014
  • In this study, four soluble homo- and co-polyimides using 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride (DOCDA) and 4,4'-diaminodiphenyl ether (ODA) monomers were synthesized to develop the gas separation membrane with good $CO_2/CH_4$ separation properties. To prepare the copolyimides, 20 mol% of three dianhydrides - (4,4'-(hexafluoroisoproplidene)diphthalic anhydride (6FDA), 4,4'-biphthalic anhydride (BPDA), 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA) - were added in DOCDA-ODA monomer mixture, respectively. All the synthesized homo- and co-polyimides were characterized by FT-IR. Their thermal properties were analyzed with differential scanning calorimeter (DSC). Dense membranes were prepared from these copolyimides to check their gas permeation properties for $CO_2$ and $CH_4$ gases using a time-lag method. The permeation testing results are as follows; DOCDA/ODA homopolymer showed 1.71 barrer of $CO_2$ permeability and 74.35 of $CO_2/CH_4$ selectivity. The three polyimide copolymers (DOCDA/6FDA-ODA, DOCDA/BPDA-ODA, DOCDA/BTDA-ODA) showed lower $CO_2/CH_4$ selectivities and higher $CO_2$ permeabilities than the homopolymer (DOCDA-ODA). DOCDA/6FDA-ODA showed twice times higher $CO_2$ permeabilities without severe $CO_2/CH_4$ selectivity loss than the DOCDA-ODA.

Oxygen Permeation Properties of La0.7Sr0.3Co0.3Fe0.7O3-δ Membrane (La0.7Sr0.3Co0.3Fe0.7O3-δ 분리막의 산소투과특성)

  • Son, Sou Hwan;Kim, Jong-Pyo;Park, Jung Hoon;Lee, Yongtaek
    • Korean Chemical Engineering Research
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    • v.47 no.3
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    • pp.310-315
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    • 2009
  • Perovskite-type ceramic powder, $La_{0.7}Sr_{0.3}Co_{0.3}Fe_{0.7}O_{3-{\delta}}$, have been synthesized successfully by the citrate method. As a result of TGA for precursor, metal-citrate complex in precursor was decomposed in the temperature range of $150{\sim}650^{\circ}C$. XRD analysis showed the single perovskite structure was observed over $1,000^{\circ}C$ without impurities. Typical dense membrane with 1.6 mm thickness has been prepared using as-prepared powder by pressing unilaterally and sintering at $1,300^{\circ}C$. The electrical conductivity of $La_{0.7}Sr_{0.3}Co_{0.3}Fe_{0.7}O_{3-{\delta}}$ membrane increased with increasing temperature at atmosphere of air and then decreased over $600^{\circ}C$ due to oxygen loss from the crystal lattice. The oxygen flux of $La_{0.7}Sr_{0.3}Co_{0.3}Fe_{0.7}O_{3-{\delta}}$ membrane in the range of 700 to $950^{\circ}C$ increased with the increasing temperature from 0.045 to $0.415ml/cm^2{\cdot}min$. The activation energy for oxygen permeation was calculated to be 89.17 kJ/mol.

Numerical Analysis for Separation of Methane by Hollow Fiber Membrane with Cocurrent Flow (병류흐름 중공사 분리막에 의한 메탄 분리 수치해석)

  • Lee, Seungmin;Seo, Yeonhee;Kang, Hanchang;Kim, Jeonghoon;Lee, Yongtaek
    • Korean Chemical Engineering Research
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    • v.53 no.3
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    • pp.295-301
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    • 2015
  • A theoretical analysis was carried out to examine the concentration behavior of methane from a biogas using a polysulfone membrane. After the governing equations were derived for the cocurrent flow mode in a membrane module, the coupled nonlinear differential equations were numerically solved with the Compaq Visual Fortran 6.6 software. At the typical operating condition of mole fraction of 0.7 in a feed stream, the mole fraction of methane in the retentate increased to 0.76 while the normalized retentate flow rate to the feed flow rate decreased from 1 to 0.79. When either the mole fraction of methane in a feed increased or the pressure of the feed stream increased, the methane mole fraction in the retentate increased. On the other hand, it was found that as either the membrane area decreased or the ratio of the permeate pressure to the feed pressure increased, the methane mole fraction in the retentate decreased. In case that the stage cut increased, the methane mole fraction in the retentate increased while the recovery of methane slightly decreased.

Analysis of Amine Absorbents Volatility Based on the Chemical Structure (아민 흡수제의 화학구조에 따른 휘발 특성)

  • Lee, Kyung Ja;Lee, Ji Hyun;Kwak, No Sang;Lee, In Young;Kim, Jun Han;Eom, Yong Seok;Jang, Kyung Ryoung;Shim, Jae Goo;Lee, Yongtaek
    • Korean Chemical Engineering Research
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    • v.50 no.2
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    • pp.348-352
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    • 2012
  • Amine volatility occurring on the $CO_2$ capture process may result in significant economic losses and environmental impact. In this study, using an volatility measurement apparatus, we measured a amine volatility of various amines including MEA(Monoethanolamine), MDEA(N-Methyldiethanolamine), Pz(Piperazine), AMP(2-Amino-2-methyl-1-propanol), 2-MP(2-Methylpiperazine), DGA(Diglycolamine). For the quantitative analysis of volatility, we analyzed the effects of temperature and $CO_2$ loading using an gas chromatography analysis. The result shows that the amine volatility was increased by increasing Henry's constant(MDEA$-CH_3$)(for AMP).

The influence with buddhist music appearing in PanYeombul out of Ogu exorcism of East coast - focused on the song by Kim Janggil - (동해안 오구굿 중 판염불에 나타난 불교음악의 영향 - 김장길의 소리를 중심으로 -)

  • Seo, Jeong-mae
    • (The) Research of the performance art and culture
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    • no.34
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    • pp.277-313
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    • 2017
  • This study is to find out the correlation with buddhist music after analyzing the rhythm of six pieces of PanYeombul sung by Kim Janggil out of Ogu exorcism of East coast the findings summarized are as follows. First, PanYeombul by Kim Janggil, performed on Oct, 16, 2016, was composed of , , , , , , , , , , and . Still, even if PanYeombul is performed by the same male shaman, the composition can be added or left out depending on some circumstances, which means the procedures are flexible. Seeing that there is common component of in additoin to compared with Kimyongtaek, it can be said that the component of is an important part in PanYeombul of Ogu exorcism of East coast Second, is usually referred to 'SinmyojangguDaedalani' in buddhist ritual, While Kim yongtaek accepts this practice in title, Kim Janggil uses 'YeomhwajangguDaedalani' as the title which makes his song different from others. Yeomhwa means "picking up flowers with fingers" which has been used in buddhism, not in common Considering this fact, the conclusion can be reached that by using the term 'Daedalani' from a buddhist chant, but making differentiation from buddhism, Kim Janggil is making the effort to be different from buddhist rituals. give some unique meaning to shaman rituals. Third, PanYeombul of Ogu exorcism of East coast may be divided into two main parts - the former part is PanYeombul and the latter part is Jiokga. In performing PanYeombul, male shaman sits singing alone and playing Jing himself, on the other hand, in case of Jiokga, he stands singing a solo with gwaeggwari in his hand accompanied by other musicians with the rhythm of Samgongjaebi. As the song and the accompaniment are in the form of giving and taking like duet. it is in peak in terms of music. Accordingly, PanYeombul can be divided into PanYeombul and Jiokga, But since it is performed by one male shaman and sung a solo, it is usually seen as one procedure. Jing, which is a kind of accompaniment in PanYeombul by Kim Janggil, has the role to distinguish a phrase and settle the musical paragraph. When the buddhist chant with one word-one note is performed. it requires the performer to catch his or her breath or clear throat. Just then, Jing comes out for filling out the intervals. Also, its role to distinguish a phrase and settle the musical paragraph helps make it clear to deliver words. The rhythm of Jing is mostly made up of small triple time except equal small binary time, comes out with overwhelmingly more frequency of Sutsoe(♪♩) than Amsoe(♩♪), and often shows syncopation. By often using Off Beat or short-long rhythm even in accompaniment of equal small binary time, he tris to give some variation to monotonous and equal rhythm for the musical vitality. These are similar to Sutsoe rhythm which can evoke tension and Kim Janggil makes these things his characierisiic of rhythm. Fifth, all the pieces consist of mi, sol, la, do, re and the descending melody like do'${\searrow}$la${\searrow}$sol${\searrow}$mi appears most frequently. The descending melody usually arouses the feeling of sorrow, so the sadness for the deceased is presented properly, which suggests his musical talent. Generally, pieces take on Menari-tori as a whole where the length of sol appears for a short time in descending la${\searrow}$sol${\searrow}$mi of perfect four degrees. Sixth, Even he accepts the lines of buddhist chant, he changes them in some degree. For example, he inserted some words between lines like 'Wonwangsaeng' and 'NamuAmitabul' and added Korean words like hapsosa to the lines of buddhist service written in Chinese character. Also, he inserted some words like 'iiiiiii~' to express the feeling of sadness. These are to maximize the desire of the deceased to go to the heaven and at the same time to diminish the sign of buddhism and strengthen the features of shamanism. Seventh, the effort to decrease the sign of buddhism is made in pasting lines of two songs. For example, Between the last words 'Wonsuaenapsu of Dage and the first words 'Jisimgwimyeongrye' of Chiljeongrye, there is usually a short pause to distinguish paragraphs, But he continues two songs without any pause to get rid of the feelings of buddhist chant. In terms of melody, he makes a distance from buddhist chant in an effort that he gives some traits to shaman rituals which are different from buddhist even if he uses the lines of buddhist rituals. Eighth, the analyzed pieces can be in four categories - no regular melody , , equal small binary time , eotmori melody of ten eighth time with 3+2+3+2 mixed small time . and Samgongjaebi melody 3+2+3 mixed small time . Each piece has its unique melody. Although of buddhist ritual is often performed, by using eotmori melody, he evokes the feeling of shaman and is another example of giving unique characteristic to the shaman of East coast by using Samgongjaebi melody.