• 제목/요약/키워드: Reductive

검색결과 472건 처리시간 0.026초

시멘트/슬래그/Fe(II) 시스템에 의한 NAPL TCE의 분해 특성

  • 박정현;강완협;황인성;박주양
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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    • pp.218-222
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    • 2004
  • Batch slurry experiments were conducted to develop cement/slag/Fe(II) system that could treat hazardous liquid wastes containing halogenated organic solvents. Portland cement in combination with Fe(II) was reported to reductively dechlorinate chlorinated organics in a modified solidification/stabilization process. TCE (trichloroethylene) was used a model halogenated organic solvent. The objectives of this study were to assess the feasibility of using cement and steel converter slag amended with Fe(II) as a low cost abiotic reductive dechlorination and to investigate the kinetics of TCE dechlorination over a wide range of TCE concentration. From the result of screening experiments, cement/slag/Fe(II) system was identified as a potentially effective system to treat halogenated organic solvent. Kinetic studies were carried out to further investigate degradation reaction of TCE NAPL (Non Aqueous Phase Liquids) in cement/slag/Fe(II) systems by using batch slurry reactors. Degradation rate of TCE solution in this system can be explained by pseudo-first-order rate law because the prediction with the rate law is in good agreement with the observed data.

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한국전통건축에서 나타나는 미니멀리즘적 특성에 관한 연구 (A Study on Minimal Characteristics of Korean Traditional Architecture)

  • 배준현;권성진
    • 한국실내디자인학회논문집
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    • 제25호
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    • pp.169-175
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    • 2000
  • Since the late 19th Century, modern architecture of definite figure and form shared similar concepts on space and from with the abstract art, pursuing the geometric purity and the abstraction. So the reductive approach had been taken in modern architecture as well as on modern art. The 1960 minimal art had experimented an extreme reduction with the cubic forms and the plane canvases, embodying so called minimal-art content, it was just another version of modernism art interpreted by the extreme reduction. The reduction is a characteristics of modernism adopted in every art field, including architecture. Not from the apparent, but from the essential quality of architectural form, figure and space resulting from the reductive approach, a building in this trend schould be judged and appreciated. In many aspects, Korean traditional architecture has been shown the characteristics of Minimal Architecture. With these points of view, this study analyzes characteristics of Korean traditional architecture with above contents through the form and space.

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STABLE CLASS OF EQUIVARIANT ALGEBRAIC VECTOR BUNDLES OVER REPRESENTATIONS

  • Masuda, Mikiya
    • 대한수학회지
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    • 제39권3호
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    • pp.331-349
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    • 2002
  • Let G be a reductive algebraic group and let B, F be G-modules. We denote by $VEC_{G}$ (B, F) the set of isomorphism classes in algebraic G-vector bundles over B with F as the fiber over the origin of B. Schwarz (or Karft-Schwarz) shows that $VEC_{G}$ (B, F) admits an abelian group structure when dim B∥G = 1. In this paper, we introduce a stable functor $VEC_{G}$ (B, $F^{\chi}$) and prove that it is an abelian group for any G-module B. We also show that this stable functor will have nice properties.

Synthesis of N,N-Dimethylacetamide from Carbonylation of Trimethylamine by Rhodium(I) Complex Under Anhydrous Condition

  • Hong, Jang-Hwan
    • 통합자연과학논문집
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    • 제8권4호
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    • pp.235-243
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    • 2015
  • Rhodium(I)-complex of $[Rh(CO)_2I_2{^-}]$ catalyzed carbonylation of anhydrous-trimethylamine in the presence of methyl iodide to give DMAC (N,N-dimethylacetamide) in no solvent. The catalyst had been reused 20 times, the analyses and distillation of collected products showed that the yields of DMAC, MAA (N-methylacetamide), and DMF (N,N-dimethylformamide) were 82.3%, 12.6%, and 4.4%. The conversion rate of trimethylamine was 99 % and the selectivity of DMAC was 82.3% with TON (Turnover Number) of 700. Stepwise procedure of inner-sphere reductive elimination for the formation of DMAC was suggested instead of acyl iodide intermediate.

Reductive Dechlorination of Tetrachloroethylene in Soils by Fe(II)-Based Degradative Solidification/Stabilization

  • Hwang, Inseong;Batchelor, Bill
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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    • pp.49-52
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    • 2001
  • An experimental study was conducted to test the feasibility of degradative solidification/stabilization (DS/S) process in treating tetrachloroethylene (PCE) in solid phase systems. The Fe(II)-based ds/s process successfully treated PCE in a soil at the reaction rates that would not allow significant release of the contaminant in the environment. A leach model was also developed that could describe the relative importance of leaching and degradation in ds/s. The first and second Damkohler numbers and dimensionless time were important parameters that determined leaching precesses in wastes treated by ds/s.

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Compositional Sugar Analysis of Antitumor Polysaccharidees by High Performance Liquid Chromatography and Gas Chromatography

  • Kim, Yeong-Shik;Park, Kyung-Shin;Park, Ho-Koon;Kim, Sung-Whan
    • Archives of Pharmacal Research
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    • 제17권5호
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    • pp.337-342
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    • 1994
  • Carbohydrate analysis is important in studying structure and activity of complex polysaccharides. New analytical method was applied to get an information on the composition of polysaccharides showing antitumor activity. Monosaccharides were labeled with 7-amino-1, 3-naph-thalenedisulfonic acid (7-AGA) by reductive amination and separated by HPLC. Five kinds of polysaccharides from Basidiomycetes were hydrolyzed and analyzed in combination with electrophresis and HPLC. At the same time, alditol acetate derivatives were prepared and analyzed by gas chromatography. Two different techniques using different derivatization methods showed very similar results. The monosaccharides from Coriolus versicolor and Cordyceps militaris were glucose and galactose. Phellinus linteus composed of glucose, glactose, mannose, arabinose and fucose. The HPLC method with fluorescence detector was very sensitive compared to other methods.

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0가 철분을 이용한 유기염소화합물의 환원적 탈염소화 (Reductive Dechlorination of Chlorinated Oraganic Compounds Using Zero-Valent Iron)

  • 이창수;배우근
    • 한국산업융합학회 논문집
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    • 제4권4호
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    • pp.427-432
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    • 2001
  • The purpose of study is to examine the sensitivity of the rate of degradation to initial TCE concentration and iron concentration in the solution. The batch tests were executed to assess the degradation rate at varying initial conditions. First order rate constants($k_a$) were more rapid with the lower initial TCE concentration, Howere the correleation was not always linear between $k_a$ and initial TCE concentration. $k_a$ was proportionally increased as the increasing surface area. It implied that the effective reactive surface area acted as the limiting factor on the reductive dechlorination of TCE by iron.

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염화에텐의 환원성 탈염소화 모텔을 이용한 수소 경쟁에 대한 평가

  • 이일수;배재호
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.117-121
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    • 2002
  • A numerical model that describes the reductive dechlorination of tetrachloroethene(PCE) to ethene via cis-dichloroethene(CDCE) was developed. The model included two separated dehalogenator groups : one for PCE transformation to cDCE via TCE and the other for cDCE dehalogenation to ethene via VC, competitive inhibition between different chloroethene electron accepters, and competition for H$_2$ between dechlorination and methanogens. Model simulations suggest first, that PCE dechlorinators are better competitive with methanogens than cDCE dechlorinators. Second, not only the initial relative population size of dehalogenators and H$_2$-utilizing methanogens but also electron donor delivery strategies used greatly affects the degree of dehalogenation. As a result, all of factors in the above must be considered in order to achieve economical and successful bioremediation of contaminated soil and groundwater with chlorinated solvents.

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