• Title/Summary/Keyword: enrichment process

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Headspace Hanging Drop Liquid Phase Microextraction and GC-MS for the Determination of Linalool from Evening Primrose Flowers

  • Kim, Nam-Sun;Jung, Mi-Jin;Yoo, Zoo-Won;Lee, Sun-Neo;Lee, Dong-Sun
    • Bulletin of the Korean Chemical Society
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    • v.26 no.12
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    • pp.1996-2000
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    • 2005
  • Headspace hanging drop liquid phase micro-extraction (HS-HD-LPME) is studied as a novel solvent-based sample pretreatment method for floral volatile aroma compounds. This paper reports on application of the HSHD- LPME combined with GC-MS for the analysis of linalool component emitted from evening primrose flowers. The effect of several variables on the method performance was investigated. Additionally, the separation of enantiomers on a cyclodextrin capillary column was performed to identify chirality of (−)-linalool component. Since the unsurpassed volume of a few micro-liters of solvent is used, there is minimal waste or exposure to toxic organic solvents. This method enables to combine extraction, enrichment, clean-up, and sample introduction into a single step prior to the chromatographic process.

A Study of Cleaning on the Biofilm of Stone Cultural Properties (석조문화재 생물막 제거 및 처리방안 연구)

  • Chung, Yong-Jae;Seo, Min-Seok;Lee, Kyu-Shik;Hwang, Jin-Ju
    • 보존과학연구
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    • s.26
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    • pp.5-25
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    • 2005
  • A consideration number of investigation have begun to elucidate the essential role biological agents play in the deterioration of stone. What is becoming clear is that many factors affect the durability of stone. Physical, chemical, and biological agentsact in co-association, ranging from synergistic to antagonistic, to deteriorate stone. Biodeterioration has usually been considered to be a degradation process following the initial deterioration effects of inorganic agents, especially objects of cultural value such as pagoda, stature of Buddha etc. These agents were thought to condition stone surfaces for microbial contamination due to structural changes and enrichment of inorganic organic nutrient substrates. This report concentrates on the action of biodeteriogens from bacteria to algae and higher plants. Preventive and remedial methods are surveyed, as are a selection of chemical treatments.

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The Effects of Feuerstein's FIE Program on Gifted Children's Executive Function (Feuerstein의 FIE 프로그램이 영재아의 실행기능에 미치는 효과)

  • Kil, Kyung-Suk
    • Journal of the Korean Home Economics Association
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    • v.47 no.6
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    • pp.121-133
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    • 2009
  • The purpose of this study was to assess the efficacy of Feuerstein's program on Gifted children's executive function. The subjects for this study were 40 Gifted children (3th year elementary students) from KAGE. Twenty were randomly allocated to the experiment group and the other 20 to the control group. The results of this study were as follows: The experiment group exhibited statistically significant improvement in attention control, cognitive flexibility and information process procedure compared to the control group. The results proved that FIE program had an effect on improvement of executive functions in gifted children.

Pragmatic contributions to the identification of explicatures (명시의미의 구명에 따른 화용론적 기여)

  • Kim, Chang-Ik
    • English Language & Literature Teaching
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    • v.9 no.spc
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    • pp.149-165
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    • 2003
  • This paper is aimed at the investigation of pragmatic contributions to the identification of explicatures. An explicature is the result of fleshing out the semantic representation of an utterance. The basic assumption of the paper is that the process of the developing the semantic representation into an explicature depends heavily on contextual information. Therefore, we are concerned with the way in which hearers use contextual information to flesh rut or develop the semantic representation of an utterance. The identification of explicatures includes both the recovery of the proposition expressed and the recovery of what we called higher-level explicatures. There are three subtasks involved in the recovery of the proposition expressed: reference assignment disambiguation and enrichment On the other hand, there are two subtasks involved in the recovery of higher-level explicatures: attitudes and speech acts.

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An adaptive X-FEM and its application to shape optimization (적응 확장 유한요소기법과 형상최적설계로의 응용)

  • Yu, Yong-Gyun;Huh, Jae-Sung;Tezuka, Akira;Kwak, Byung-Man
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.538-543
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    • 2007
  • A procedure is proposed to generate optimal grid with minimal user intervention while keeping a prescribed level of accuracy, using an adaptive X-FEM and applied to shape optimization. In spite of various advantages of X-FEM, however, there are several obstacles for practical applications. Because of using a uniform background mesh and additional degree of freedoms for enrichment, an X-FEM is usually computationally more expensive than traditional finite element method. Furthermore, there are often accuracy problems. For an automatic procedure of optimal mesh generation, an h-adaptive scheme and a posteriori error estimation obtained by a post-processing process are utilized. The procedure is shown by 2-D shape optimization examples.

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Enrichment of Oxygen and process engineering aspects using polysulfone hollowfiber membrane (폴리수폰 중공사막에 의한 산소농축 및 공정변수의 영향)

  • 조정식;김종수;이광래
    • Proceedings of the Membrane Society of Korea Conference
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    • 1997.10a
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    • pp.65-66
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    • 1997
  • 1. 서론 : 현재의 막분리 기술로는 단 단계 분리공정(single-stage separation)으로 약 40%의 산소농축공기(oxygen-enriched air)를 얻을 수 밖에 없지만 심냉법(cryogenic techniques)보다는 에너지 소비율이 적으며, 공정이 비교적 간단하기 때문에 용도에 따라 순 산소를 꼭 필요로 하지 않는 제철소, 발전소 등의 연소분야, 호흡기 환자를 위한 의료분야, 생물공학이나 항공기 분야 등에 편리하게 이용될 수 있다. 이와 같이 용도가 다양한 산소를 분리막을 이용하여 보다 편리하고 값싸게 얻기 위해서는 산소와 질소의 막투과에 대한 새로운 지식을 얻고 막투과가 기체의 어떤 성질에 지배되고 있는가를 조사할 필요가 있다. 본 연구에서는 고무상 고분자막(rubbery polymer membrane)에 대한 산소/질소의 수착특성과 순수한 기체의 투과율(permeation rate)을 기초로 하여 혼합기체의 투과율, 분리인자(separation factor), 막분리 공정변수에 의한 중공사 분리막에서의 기체분리특성에 대하여 연구하였다.

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Electrostatic Ejection of Micro-droplets Containing Carbon Nanotubes (탄소나노튜브를 포함한 마이크로 액적의 정전기적 토출)

  • Kim Yong-Jae;Lee Sukhan;Ko Han Seo;Byun Doyoung;Han Sangjoon;Yang Ji Hye;Baik Seunghyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.1 s.244
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    • pp.82-86
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    • 2006
  • Carbon nanotubes have attracted much attention as future mechanical and electronic materials. However, manipulating techniques are not well developed yet. Here we propose to use electrostatic drop-on-demand devices to eject micro-droplets containing micelle-suspended single-walled carbon nanotubes. A simple electrostatic force analysis and photographic studies of droplet ejection process are presented. The analytical analysis shows that semiconducting species have higher electrostatic force density. However, enrichment of specific electronic types is not clear at large size droplets produced in this study. A micro-scale jetting device is being produced to prove the suggested behavior.

A feruloyl esterase derived from a leachate metagenome library

  • Rashamuse, Konanani;Sanyika, Walter;Ronneburg, Tina;Brady, Dean
    • BMB Reports
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    • v.45 no.1
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    • pp.14-19
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    • 2012
  • A feruloyl esterase encoding gene (designated fae6), derived from a leachate metagenomic library, was cloned and the nucleotide sequence of the insert DNA determined. Translational analysis revealed that fae6 consists of a 515 amino acid poly-peptide, encoding a 55 kDa pre-protein. The Fae6 primary structure contained the G-E-S-A-G sequence, which corresponds well with a typical catalytic serine sequence motif (G-x-S-x-G). The fae6 gene was successfully over-expressed in E. coli and the recombinant protein was purified to 8.4 fold enrichment with 17% recovery. The $K_M$ data showed Fae6 has a high affinity to methyl sinapate while thermostability data indicated that fae6 was thermolabile with a half life ($T_{1/2}$) < 30 min at $50^{\circ}C$. High affinity for Fae6 against methyl sinapate, methyl ferulate and ethyl ferulate suggest that the enzyme can be useful in hydrolyzing ferulated polysaccharides in a biorefinery process.

Effect of Reverse Transformation on the Microstructure and Retained Austenite Formation of 0.14C-6.SMn Alloy Steel (0.14C-6.5Mn 합금강의 미세조직과 잔류오스테나이트 형성에 미치는 역변태처리의 영향)

  • Song, K.H.;Lee, O.Y.
    • Journal of the Korean Society for Heat Treatment
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    • v.13 no.4
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    • pp.253-258
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    • 2000
  • The present study aimed to develop the TRIP(transformation induced plasticity) aided high strength low carbon steel sheets using reverse transformation process. The cold-rolled 0.14C-6.5Mn steel was reverse-transformed by slow heating to intercritical temperature region and air cooling to room temperature. An excellant combination of tensile strength and elongation of $98.3kgf/mm^2$ and 44.4% appears. This combination comes from TRIP phenomena of retained austenite during deformation. The stability of retained austenite Is very Important for the good ductility and it depends on diffusion of carbon and manganese during reverse transformation. The air cooling after holding at intercritical temperature retards the formation of pearlite and provides the carbon enrichment in retained austenite, resulting the increase of elongation in cold-roiled TRIP steel.

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Decision Making Model for Agricultural Reservoir using PROMETHEE-AHP (PROMETHEE-AHP를 이용한 농업용 저수지의 의사결정모형)

  • Choi, Eun-Hyuk;Bae, Sang-Soo;Jee, Hong-Kee
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.5
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    • pp.57-67
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    • 2012
  • This paper presents the Multi Criteria Decision Making (MCDM) to evaluate water resources plan for agricultural reservoir. Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) and Analytic Hierarchy Process (AHP) were used to estimate weight and priority of alternatives to find out the most reasonable and efficient way of water resources assessment. The 6 criteria that both decision maker and beneficiary are satisfied have been identified to secure agricultural water resources and then the priority of 10 subcriteria was set. An enhanced PROMETHEE-AHP model was used to perform pairwise comparison and find out the priority of each alternative because the existing decision making model have uncertainty and ambiguity. Comparison analysis of decision making models was carried out to find a way of suitable decision making and validity of PROMETHEE-AHP model was suggested.