• 제목/요약/키워드: UAA

검색결과 8건 처리시간 0.017초

고온 처리된 활성알루미나를 이용한 불소 제거 (Removal of Fluoride Using Thermally Treated Activated Alumina)

  • 박성직;김재현;이창구;박정안;최낙철;김성배
    • 대한환경공학회지
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    • 제32권10호
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    • pp.986-993
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    • 2010
  • 본 연구에서는 열처리한 활성알루미나의 불소흡착특성을 분석하였다. 이를 위하여 평형 및 동적 흡착실험을 수행하였고, 용액 pH의 영향과 음이온의 존재에 따른 흡착 특성을 살펴보았다. 또한, 열처리한 활성알루미나의 여재특성을 분석하기 위하여, 전계방출주사현미경(field-emission scanning electron microscope), energy-dispersive spectrometry, X선 회절(X-ray Diffractometer, XRD)분석, 그리고 Brunauer-Emmett-Teller (BET) 비표면적 분석을 수행하였다. 다양한 온도(100, 300, 500, $700^{\circ}C$) 에서 열처리한 활성알루미나의 흡착능을 비교한 결과, 높은 불소 농도(50, 100, 200 mg/L)에서 열처리 온도가 높아짐에 따라서 활성알루미나의 흡착량이 증가하는 것으로 나타났다. 특히, 불소 초기농도 200 mg/L에서는 $700^{\circ}C$에서 고온처리한 활성알루미나(AA700)의 흡착량이 열처리하지 않은 활성알루미나(UAA)보다 3.67배 큰 것으로 나타났다. AA700과 UAA의 BET분석 결과, UAA의 단위질량당 비표면적이 AA700의 비표면적보다 약 2배 큼을 알 수 있었다. XRD 분석결과에 의하면, AA700의 결정구조는 Al2O3인 반면, UAA는 boehmite (AlOOH)와 bayerite ($Al(OH)_3$)가 혼합된 형태로 구성되어 있었다. 열처리에 의하여 비표면적이 감소하였음에도 불구하고, AA700의 불소 흡착능이 UAA에 비하여 증가한 이유는 결정구조의 변화 때문으로 판단된다. AA700의 동역학적 흡착실험결과, 불소의 흡착은 24 h 경과 후에 평형에 도달하였다. 또한, 평형 흡착실험결과에 의하면, 여재 당 불소의 최대 흡착량은 5.70 mg/g으로 나타났다. 용액 pH의 영향을 분석한 결과, pH 7에서 불소 흡착이 가장 높았으며, 산성과 알칼리성에서는 불소 흡착이 감소하는 것으로 나타났다. 음이온의 영향을 분석한 결과, 인산염, 질산염, 중탄산염은 불소 흡착을 감소시키는 것으로 나타났다. 본 연구에 의하면, 상용화된 활성알루미나를 이용하여 불소를 제거할 경우, 고온처리를 통하여 활성알루미나의 흡착능을 증가시킬 수 있을 것으로 판단된다.

Site-Specific Labeling of Proteins Using Unnatural Amino Acids

  • Lee, Kyung Jin;Kang, Deokhee;Park, Hee-Sung
    • Molecules and Cells
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    • 제42권5호
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    • pp.386-396
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    • 2019
  • Labeling of a protein with a specific dye or tag at defined positions is a critical step in tracing the subtle behavior of the protein and assessing its cellular function. Over the last decade, many strategies have been developed to achieve selective labeling of proteins in living cells. In particular, the site-specific unnatural amino acid (UAA) incorporation technique has gained increasing attention since it enables attachment of various organic probes to a specific position of a protein in a more precise way. In this review, we describe how the UAA incorporation technique has expanded our ability to achieve site-specific labeling and visualization of target proteins for functional analyses in live cells.

카오스 무인 비행체에서의 장애물 회피 방법 (Obstacle Avoidance Method in the Chaotic Unmanned Aerial Vehicle)

  • 배영철;김이곤;김천석
    • 한국지능시스템학회논문지
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    • 제14권7호
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    • pp.883-888
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    • 2004
  • In this paper, we propose a method to avoid obstacles that have unstable limit cycles in a chaos trajectory surface. We assume all obstacles in the chaos trajectory surface have a Van der Pol equation with an unstable limit cycle. When a chaos UAVs meet an obstacle in an Arnold equation, Chua's equation and hyper-chaos equation trajectory the obstacle reflects the UAV( Unmanned Aerial Vehicle).

Application of Nano-sized Amphiphilic Polyurethane Particles for The Remediation of PAH-Contaminated Soil:Sorption to Soil and PAH Solubilization

  • Park, Heon-Sik;Ahn, Ik-Sung;Kim, Ju-Young;Park, Sung-Yong;Shin, Young-Seob
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.183-186
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    • 2002
  • Experiments in the batch soil/aqueous systems were conducted to compare the sorption onto soil and extraction efficiency of sorbed phenanthrene in the presence of the micelle-forming anionic surfactant(SDS) or the micelle-like amphiphilic nano-sized polyurethane particles. Micelle-like amphiphilic nano-sized polyurethane(APU) particles synthesized from amphiphilic urethane acrylate anionomers(UAA) could solubilize phenanthrene within their hydrophobic interiors as the same way that surfactants micelles did in aqueous phase.

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Three ORF-Containing Group I Introns in Chloroplast SSU of Caulerpa sertularioides (Ulvophyceae) and Their Evolutionary Implications

  • Lee, Jung-Ho;Manhart, James R.
    • ALGAE
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    • 제18권3호
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    • pp.183-190
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    • 2003
  • Except for a group I intron in trnL-uaa occuring in eubacteria and plastids, group I introns are rarely documented in plastid genomes. Here, we report that a green alga, Caulerpa sertularioides, contains three group IA3 introns in the 16S gene (cpSSU), CS-cpSSU.i1, CS-cpSSU.i2 and CS-cpSSU.i3. Each intron has an open reading frame with LAGLIDADG motifs. CS-cpSSU.i1orf and CS-cpSSU.i3orf occur at Loop 6 in the intron secondary structure and CScpSSU. i2orf at Loop 8. CS-cpSSU.i1orf and CS-cpSSU.i2orf contain both LAGLI-DADG motifs but CS-cpSSU.i3orf has only one. CS-cpSSU.i1 and CS-cpSSU.i2 share the insetion sites and the ORFs at Loop 6 and 8 with CpSSU·1 and CpSSU·2 introns of Chlamydomonas pallidostigmatica (Chlorophyceae). In contrast, CS-cpSSU.i3, containing 28 copies of GAAATAT at Loop 6, is a novel intron found only in Caulerpa sertularioides. Possible scenarios of the evolution of the three introns and their possible use in systematic research are discussed.

Phylogenetic Analysis of Pines Based on Chloroplast trnT-trnL Intergenic Spacer DNA Sequences

  • Um, Yurry;Park, Won-Kyu;Jo, Nam-Su;Han, Sim-Hee;Lee, Yi
    • Journal of Forest and Environmental Science
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    • 제30권3호
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    • pp.307-313
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    • 2014
  • This study was conducted to distinguish the pines that are too similar to differentiate using conventional methods. Pinus densiflora and Pinus sylvestris have similar anatomical structure. They both have window-like pits and dentate ray tracheids, so it is not easy to distinguish the plants. We tried to find molecular markers by comparing chloroplast DNA sequences to differentiate the pines growing in Korea. We used P. densiflora, P. densiflora for. multicaulis, P. sylvestris, P. rigida, P. rigitaeda, P. koraiensis, and P. bungeana for this study. We found that the non-coding intergenic region of trnT(UGU) and trnL(UAA) genes have differences among the species. We designed a primer set to amplify the region efficiently and compared the PCR product sequences using CLC Workbench programs to find the polymorphism. We could distinguish the species using the sequences of the amplified region and the sequences were reproducible from the pines collected in Korea.

Molecular Data Concerning Alloploid Character and the Origin of Chloroplast and Mitochondrial Genomes in the Liverwort Species Pellia borealis

  • Pacak, Andrezej
    • Journal of Plant Biotechnology
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    • 제2권2호
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    • pp.101-108
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    • 2000
  • The liverwort Pellia borealis is a diploid, monoecious, allopolypliod species (n=18) that as it was postulated, originated after hybridization and duplication of chromosome sets of two cryptic species: Pellia epiphylta-species N (n=9) and Pellia epiphylla-species 5 (n=9). Our recent results have supported the allopolyploid origin of P.borealis. We have shown that the nuclear genome of P.borealis consists of two nuclear genomes: one derived from P.epiphylla-species N and the other from P.epiphylla-species 5. In this paper we show the origin of chloroplast and mitochondrial genomes in an allopolyploid species P.borealis. To our knowledge there is no information concerning the way of mitochondria and chloroplast inheritance in Brophyta. Using an allopolyploid species of p. borealis as a model species we have decided to look into chloroplast and mitochondrial genomes of P.borealis, P.epiphylla-species N and P.epiphylla-species S for nucleotide sequences that would allow us to differentiate between both cryptic species and to identify the origin of organelle genomes in the alloploid species. We have amplified and sequenced a chloroplast $tRNA^{Leu}$ gene (anticodon UAA) containing an intron that has shown to be highly variable in a nucleotide sequence and used for plant population genetics. Unfortunately these sequences were identical in all three liverwort species tested. The analysis of the nucleotide sequence of chloroplast, an intron containing $tRNA^{Gly}$ (anticodon UCC) genes, gave expected results: the intron nucleotide sequence was identical in the case of both P.borealis and P.epiphyllaspecies N, while the sequence obtained from P.epiphyllasperies S was different in several nucleotide positions. These results were confirmed by the nucleotide sequence of another chloroplast molecular marker the chloroplast, an intron-contaning $tRNA^{Lys}$ gene (anticodon UUU). We have also sequenced mitochondrial, an intron-containing $tRNA^{Ser}$ gene (anticodon GCU) in all three liverwort species. In this case we found that, as in the case of the chloroplast genome, P.borealis mitochondrial genome was inherited from P.epiphylla-species N. On the basis of our results we claim that both organelle genomes of P.borealis derived from P.epiphylla-species N.

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미국의 중재판정 취소에 관한 연구: 판례법과 제정법의 조화를 중심으로 (A Study of the Vacating of Arbitral Awards by Finding Harmony of Case Law with Statutory Law of the United States)

  • 김진현;정용균
    • 한국중재학회지:중재연구
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    • 제22권2호
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    • pp.125-157
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    • 2012
  • This study is to vindicate the vacation of arbitral awards in the United States. It focuses on the harmony of case law with statutory law of the United States. Until the early twentieth century, the American legal system, having adopted the English common law view, harbored a hostile attitude toward arbitration. The purpose of the Federal Arbitration Act (FAA) of the United States, enacted in 1925, was to eliminate the hostile attitude of courts toward arbitration. Congress is to enforce arbitration agreements into which parties have entered and to place arbitration agreements upon the same footing as other contracts. The structure of grounds for vacating arbitration awards has two layers. One is of vacating grounds with statutory origins, such as the FAA and the Uniform Arbitration Act, and the other, of vacating grounds originating from a nonstatutory, case law background. For a while, vacatur based on case law has coexisted with vacatur on statutory grounds for arbitration awards. After the Supreme Court decision in Hall Street Associates, L.L.C. v. Mattel, Inc., however, the justification of vacating based on case law has weakened. Post-Hall Street decisions of circuit courts show ways to deal with manifest disregard of the law. One of them is the harmonization of the case law grounds for vacating with the statutory grounds. It seems that the manifest-disregard-of-law and public-policy exceptions show a possibility of survival after Hall Street. However, other nonstatutory grounds for vacation of arbitration awards have no firm basis after Hall Street.

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