• Title/Summary/Keyword: separation of mixture

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The Abjection of The Mother/Colonial Country in Jamaica Kincaid's Annie John (자메이카 킨케이드의 『애니 존』에 나타난 어머니/식민지 본국의 비체화)

  • Jeong, Eun-sook
    • Journal of English Language & Literature
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    • v.57 no.2
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    • pp.285-314
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    • 2011
  • The purpose of this paper is to analyse the mother-daughter structure presented in Annie John, Kincaid's autobiographical novel as a metaphor for the relationship between the powerful colonizer and the powerless colonized. The representation of the mother in Annie John is ambiguous and ambivalent. On the one hand, the mother in the childhood, in its association with the African-rooted Caribbean world before Antigua was colonized, is represented as a person who nurtures the daughter, and embodies a paradisiacal pre-oedipal union with the daughter. On the other hand, the mother at the adolescent stage, placed in the specific colonial context of the Caribbean, is represented as a scornful person/colonizer who dominates and controls the daughter's behavior to keep her as a dependent and subjugated subject. Therefore, the two conflicting worlds, the African and the European, coexist in the contradictory figure of the mother. The theoretical basis of my argument is a mixture of Chodorow's and Kristeva's feministic psychoanalysis and Bhabha's notion of "mimicry" and "ambivalence." Kristeva's work on "abjection" is especially useful and helpful for contextualizing Annie's individuation and separation from the mother who is represented as enigmatic.

Fabrication of Fluorinated Polymeric Membranes and Their Noble Gas Separation Properties (불소 표면 개질 고분자 분리막의 제조와 노블가스 분리특성)

  • Kim, Gi-Bum;Yoon, Kuk-Ro
    • Applied Chemistry for Engineering
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    • v.21 no.4
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    • pp.475-478
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    • 2010
  • Fluorinated polymeric membranes were prepared by direct surface modification of PDMS with fluorine gas ($50{\sim}2000\;{\mu}mol/mol$ in nitrogen). The formed fluorinated polymeric membranes were characterized by FT-IR spectroscopy, GC (Gas chromatography), atomic force microscopy, and scanning electron microscopy. Direct fluorination resulted in the change of permeability and selectivity of various gases (pure gases such as $CO_2$, $O_2$, $N_2$, $C_2H_4$, mixture of He, Ne, Kr, Xe) through PDMS membranes. Fluorination resulted in the maximum 50% increase of selectivity through PDMS membrane.

초임계유체를 이용한 당 에스테르의 합성 및 분리정제

  • Seo, Deok-Gi;Kim, U-Gyeong;Kim, Gwang-Il;Yu, In-Sang;Yun, Hyeon-Hui
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.705-708
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    • 2001
  • Enzymatic synthesis and purification of sugar esters using supercritical $CO_2$ were investigated. The observed yield of suagr ester produced by transesterification of methyl glucoside and oleic acid using a lipase(Novozym 435) was 67% at 24 hours of reaction in the supercritical $CO_2$. The solubility of the fatty acids in the supercritical $CO_2$ was measured to find the conditions of supercritical separation of the fatty acids from the reaction mixture. The solubility of capric and oleic acid was 5 ${\times}$ $10^{-4}$, 1.7 ${\times}$ $10^{-4}$ mol/mol $CO_2$, respectively, varying at $35{\sim}50^{\circ}C$ and 80${\sim}$120 atm.

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Retention Mechanism of Caffeine and Tryptophan in Macroporous Poly[Methacrylic Acid-co-Ethylene Glycol Dimenthacrylate] Rods (매크로 다공성 Poly[Methacrylic Acid-co-Ethylene Glycol Dimenthacrylate] 막대에서 Caffeine과 Tryptophan의 체류 메카니즘)

  • Jin, Longmei;Yan, Hongyuan;Zheng, Jinzhu;Row, Kyung-Ho
    • KSBB Journal
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    • v.21 no.5
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    • pp.401-404
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    • 2006
  • Macroporous Poly(Methacrylic acid-co-Ethylene Glycol Dimethacrylate) Rods were in situ thermal initialized within a empty column($3.9{\times}150mm$) by free radical polymerization. The polymerization mixture was consisted of monomer, cross-linking monomer, porogenic solvent, initiator and control the ratio of these materials, column efficiency could be developed. Caffeine and tryptophan as separation substances and the retention mechanism of this kind of monolithic column was mainly hydrogen bond function.

High-Performance Liquid Chromatographic Analysis of Chrysin Derivatives on A $Nova-Pak^{\circledR}C_{18}$ Column

  • Kim, Kyoung-Soon;Shin, Joon-Su;Park, You-Mie;Lee, Sanghyun;Kim, Yang-Bae;Kim, Bak-Kwang
    • Archives of Pharmacal Research
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    • v.25 no.5
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    • pp.613-616
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    • 2002
  • A high-performance liquid chromatographic method has been developed for the separation and quantification of chrysin and synthetic chrysin derivatives (12 chrysin alkyl and 7 chrysin acyl derivatives). The chromatography was performed using a $Nova-Pak^{\circledR}C_{18}$ column. A RP-HPLC was performed by using a binary mixture (MeOH-10 mM H$_3$PO$_4$) as a mobile phase, and the column temperature was maintained at room temperature. A flow rate was 1.0 ml/min, and the effluent was monitored at a wavelenth of 280 nm. The retention times for chrysin acyl and alkyl derivatives were within 10 minutes and 20 minutes, respectively. The absolute recovery of samples were all over 96%. The detection limits were 0.1~18 ng at S/N = 3 ratio.

Separation and Detection of Nonchromophore Aliphatic Compounds by Reversed-Phase Liquid Chromatography using Ultraviolet-Absorbing Reagent (자외선 흡수물질을 이용한 역상 액체 크로마토그라피에 의한 비흡수 지방족 화합물들의 검출과 분리)

  • Lee Seung-Seok;Kang Sam-Woo;Oh Hae-Beom
    • Journal of the Korean Chemical Society
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    • v.35 no.4
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    • pp.397-404
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    • 1991
  • Nonchromophore compounds such as aliphatic acids, alcohols and tetraalkylammonium salts could be detected by indirect photometric detection on the revered-phase liquid chromatography. Benzyltriethylammonium bromide(BTEAB) was used as a detection reagent. Also, the retention mechanism and response of samples were investigated to the several factors such as pH, temperature, and concentration of MeOH as well as concentration of detection reagents in mobile phase. And some mixture of samples were able to be separated under optimum condition.

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Determination of Costunolide from Aucklandiae Radix and Substitutive Herbs by Reversed-Phase HPLC (HPLC를 이용한 목향 및 유사 한약재에 함유된 Costunolide 비교)

  • Oh, Ju-Hee;Hong, Seon-Pyo;Choi, Ho-Young;Park, Yong-Ki;Lee, Je-Hyun
    • The Korea Journal of Herbology
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    • v.23 no.3
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    • pp.61-66
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    • 2008
  • Objecives : Aucklandiae Radix is a root of Aucklandia lappa which has been widely used for regulating the flow of vital energy, invigorating the spleen, alleviating pain. Aucklandiae Radix contains the costunolide which is the main ingredient. The substitutive Aucklandiae Radix are Inulae helenii Radix, Aristolchiae Radix, Vladimiriae Radix, and Inulae racemosi Radix in Korea and China. This paper is analysised and compared the costunolide and HPLC pattern in Aucklandiae Radix and substitute herbs. Methods : Chromatographic separation performed using C18 column(Luna 5 u, 250 mm ${\times}$ 4.6 mm) with a mixture of methanol and water(65:35)(v/v). The analyses detected at UV(210 nm). Results : Optimal extraction condition of costunolide was 100% methanol for 2hr. Costunolide was detected in Aucklandiae Radix and Vladimiriae Radix, but other herbs were not detected. In Korea herbal market, Aristolchiae Radix merchandise was identified as the imported Inulae helenii Radix. Conclusions : According to above results, this method was useful identified to Aucklandiae Radix and substitutive herbs. In Korea herbal market, Aristolchiae Radix was identified as Inulae helenii Radix.

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Selective Speech Feature Extraction using Channel Similarity in CHMM Vocabulary Recognition (CHMM 어휘인식에서 채널 유사성을 이용한 선택적 음성 특징 추출)

  • Oh, Sang Yeon
    • Journal of Digital Convergence
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    • v.11 no.10
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    • pp.453-458
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    • 2013
  • HMM Speech recognition systems have a few weaknesses, including failure to recognize speech due to the mixing of environment noise other voices. In this paper, we propose a speech feature extraction methode using CHMM for extracting selected target voice from mixture of voices and noises. we make use of channel similarity and correlate relation for the selective speech extraction composes. This proposed method was validated by showing that the average distortion of separation of the technique decreased by 0.430 dB. It was shown that the performance of the selective feature extraction is better than another system.

Development of a Multi - channel Detector for Capillary Electrophoresis System (모세관 전기영동 장치용 Photodiode Array 다채널 검출기의 개발에 관한 연구)

  • Hong, Seung Guk;Kim, Hai-Dong
    • Analytical Science and Technology
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    • v.11 no.2
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    • pp.96-104
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    • 1998
  • A photodiode array multichannel detector system for capillary electrophoresis was developed. The photodiode array detector for capillary electrophoresis (CE-PDA) has 1024 photodetectors and can analyze sample by measuring UV/VIS absorption spectrum in 275~675 nm wavelength range. The CE-PDA instrument can get a spectrum in 30 ms during sample separation and can be programmed by a PC to control various experimental conditions required for sample analysis. The performance of the multichannel CE-PDA instrument was tested using L-ascorbic acid and alizarin yellow GG mixture. The reproducibility test of the CE-PDA system showed 5.6% RSD.

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Decomposition Mechanism of Waste Hard Metals using by ZDP (Zinc Decomposition Process) (ZDP(Zinc Decomposition Process)를 이용한 폐 초경합금의 분해기구)

  • Pee, Jae-Hwan;Kim, Yoo-Jin;Sung, Nam-Eui;Hwang, Kwang-Taek;Cho, Woo-Seok;Kim, Kyeong-Ja
    • Journal of the Korean Ceramic Society
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    • v.48 no.2
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    • pp.173-177
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    • 2011
  • Decomposition promoting factors and decomposition mechanism in the zinc decomposition process of waste hard metals which are composed mostly of tungsten carbide and cobalt were evaluated. Zinc volatility amount was suppressed and zinc valatilization pressure was produced in the reaction graphite crucible inside an electric furnace for ZDP. Reaction was done for 2 h at $650^{\circ}C$, which 100 % decomposed the waste hard metals that were over 30 mm thick. As for the separation-decomposition of waste hard metals, zinc melted alloy formed a liquid composed of a mixture of ${\gamma}-{\beta}1$ phase from the cobalt binder layer (reaction interface). The volume of reacted zone was expanded and the waste hard metal layer was decomposed-separated horizontally from the hard metal. Zinc used in the ZDP process was almost completely removed-collected by decantation and volatilization-collection process at $1000^{\circ}C$.