• Title/Summary/Keyword: 분자체

Search Result 1,685, Processing Time 0.025 seconds

Current status of Brassica A genome analysis (Brassica A genome의 최근 연구 동향)

  • Choi, Su-Ryun;Kwon, Soo-Jin
    • Journal of Plant Biotechnology
    • /
    • v.39 no.1
    • /
    • pp.33-48
    • /
    • 2012
  • As a scientific curiosity to understand the structure and the function of crops and experimental efforts to apply it to plant breeding, genetic maps have been constructed in various crops. Especially, in the case of Brassica crop, genetic mapping has been accelerated since genetic information of model plant $Arabidopsis$ was available. As a result, the whole $B.$ $rapa$ genome (A genome) sequencing has recently been done. The genome sequences offer opportunities to develop molecular markers for genetic analysis in $Brassica$ crops. RFLP markers are widely used as the basis for genetic map construction, but detection system is inefficiency. The technical efficiency and analysis speed of the PCR-based markers become more preferable for many form of $Brassica$ genome study. The massive sequence informative markers such as SSR, SNP and InDels are also available to increase the density of markers for high-resolution genetic analysis. The high density maps are invaluable resources for QTLs analysis, marker assisted selection (MAS), map-based cloning and comparative analysis within $Brassica$ as well as related crop species. Additionally, the advents of new technology, next-generation technique, have served as a momentum for molecular breeding. Here we summarize genetic and genomic resources and suggest their applications for the molecular breeding in $Brassica$ crop.

Hydrolytic Kinetic Resolution of Racemic Alkyl-glycidyl Derivatives by using Dimeric Chiral Salen Catalyst Containing Ga, In and TlCl3 (염화갈륨, 인듐 및 탈륨 함유 이분자형 키랄 살렌 촉매에 의한 라세믹 알킬 글리시딜레이트 유도체의 비대칭 가수분해반응)

  • Shin, Chang-Kyo;Rahul, B. Kawthekar;Kim, Geon-Joong
    • Applied Chemistry for Engineering
    • /
    • v.18 no.3
    • /
    • pp.218-226
    • /
    • 2007
  • The stereoselective synthesis of chiral terminal epoxides is of immense academic and industrial interest due to their utility as versatile starting materials as well as chiral intermediates. In this study, new dinuclear chiral Co (salen) complexes bearing gallium-, indium- and tallium-chloride have been synthesized and characterized. The mass and EXAFS spectra provided the direct evidence of formation of dinuclear complex. Their catalytic activity and selectivity have been demonstrated for the asymmetric ring opening of various terminal epoxides having ether or ester groups by hydrolytic kinetic resolution technology. The easily prepared dimeric complexes exhibited very high enantioselectivity for the asymmetric ring opening of epoxides with $H_2O$ nucleophile, providing enantiomerically enriched terminal epoxides (> 99% ee). The dimeric structured chiral salen showed remarkably enhanced reactivity and may be employed substantially lower loadings than its monomeric analogues. The system described in this work is very efficient for the synthesis of chiral epoxide and 1,2-diol intermediates

Effect of Functional Monomer on Retention Factor of Chiral Racemate (기능성 단량체가 키랄 물질의 체류인자에 미치는 영향)

  • Jin, Yin-Zhe;Row, Kyung-Ho
    • KSBB Journal
    • /
    • v.20 no.4
    • /
    • pp.260-265
    • /
    • 2005
  • In this work, molecular imprinted polymers (MIPs) using the template of the N-CBZ (carbobenzyloxy)-L-phenylalanine, MAA and 4-VPY as a monomer, EGDMA as a crosslinker and AIBN as an initiator were considered. The prepared polymer particles $(Ca.\;25-35\;{\mu}m)$ were packed into a chromatographic column $(3.9\;\times\;150\;mm)$. The chromatographic characteristics of the retention on the MIP were experimented with acetonitrile as a mobile phase at the flow rate of mobile phase, 0.5 ml/min. The retention factors and resolutions of chiral racemate of the N-CBZ-D, L-phenylalanine were measured. The results showed that the retention factor and resolution by the two co-monomer imprinting polymer were higher than the single monomer imprinting polymers, which indicated an increase in the affinity of the MIP with the sample as a result of the cooperation effect of the binding sites.

Identification of Toxic Chemicals Using Polypyrrole-Cyclodextrin Hybrids (폴리피롤-사이클로덱스트린 혼성체를 이용한 유해화합물질의 검출)

  • Bae, Joonwon
    • Applied Chemistry for Engineering
    • /
    • v.30 no.2
    • /
    • pp.186-189
    • /
    • 2019
  • Polypyrrole is a typical electrical conducting polymer, which has an excellent charge transport property. Cyclodextrins are a group of toxic-free and cyclic oligosaccharide molecules, capable of capturing low molecular weight chemicals. Considering these advantages, hybrid materials of polypyrrole and cyclodextrin can be used to detect hazardous compounds. Cyclodextrin molecules can accommodate toxic chemicals by the formation of host-guest complexes and generate electric signals, which are effectively delivered by polypyrrole backbone. In this study, the polypyrrole/cyclodextrin hybrid material was prepared using a facile wet method and included into a hydrogel. Subsequently, it was applied to a simple sensor system with a gold-patterned electrode for the detection of potentially hazardous material, methyl paraben. Compared with pristine polypyrrole, it was found that the polypyrrole/cyclodextrin hybrid showed an improved performance. This study can be an example of using environmentally benign conducting polymer/cyclodextrin hybrids as sensing media.

Effects of Irradiation Crosslinking and Molecular Weight Properties on Crosslinked PP Foaming Process (전자선 조사량과 분자량 특성이 전자선 가교 PP 발포 가공에 미치는 영향)

  • 홍다윗;윤광중;백운선;정영헌;이준길
    • Polymer(Korea)
    • /
    • v.26 no.4
    • /
    • pp.508-515
    • /
    • 2002
  • The effects of the crosslinking caused by irradiation dose, molecular weights of the foaming materials, and various foaming processes on the foam structure of the polypropylene (PP) were investigated. The maximum gel content of the PP was 48% when the sheet was irradiated with 3.2 Mrad. This high gel content improved the cell structures by providing high thermal stability. The increase of both the gel content and structural development were stopped at the irradiation dose exceeding 3.2 Mrad. The increase of the molecular weights served to help produce a foam with particularly fine and even cell structures, along with improved thermal stability as well.

The Effects of the Structural Characteristics on Properties of Their Bridging OH Groups for $AlPO_4-5$ Molecular Sieve : MNDO Calculations ($AlPO_4-5$ 분자체에서 가교 OH 그룹의 성질에 대한 구조 특성 효과 : MNDO 계산)

  • Son, Man-Shick;Lee, Chong-Kwang;Paek, U-Hyon
    • Journal of the Korean Chemical Society
    • /
    • v.37 no.9
    • /
    • pp.787-792
    • /
    • 1993
  • Semiempirical MNDO calculations are employed to study relation properties on bridging OH group with Al-O(P-O) bond length and Al-O-P bond angle of structural characteristics using birdging $(OH)_3AlOP(OH)_3$ and $(OH)_3AlOHP(OH)_3^+$ model culster. We know that the O-H bond dissociation energy of bridging OH group is increased with increasing Al-O(P-O) bond length and decreasing Al-O-P bond angle. The bridging OH group is formed into enlarged Al-O(P-O) bond length and shortened Al-O-P bond angle in bridging oxygen atom by a hydrogen migration. The negative net charge of bridging oxygen atom is increased with longer Al-O-P bond angle, while the positive net charge is decreased with longer Al-O-P bond angle.

  • PDF

Study on Carbon Dioxide Control by Using Dry Sorbent in Fludized Bed (유동층에서 dry sorbent를 이용한 CO2 제어에 관한 연구)

  • Lee, Sang-Sup;Kim, Min-Choul;Yoo, Jeong-Seok;Moon, Gil-Ho;Oh, Kwang-Joong
    • Clean Technology
    • /
    • v.9 no.4
    • /
    • pp.179-187
    • /
    • 2003
  • The technology of fluidized bed to use dry sorbent can be new technology that reduce the operating cost and make efficient operation. Therefore, this study investigated $CO_2$ control by dry sorbents with operating variables in a fluidized bed, compared with fixed bed for $CO_2$ adsorption capacity and pressure drop, and presented the $CO_2$ adsorption capacity of activated carbon, molecular sieve 5A, molecular sieve 13X, and activated alumina. As the results of this study, the basic data could be achieved for operation of fluidized bed process, and fluidized bed process presented relatively high $CO_2$ adsorption capacity and low pressure drop with the increase of gas velocity. In addition, molecular sieve 5A showed 1.1~3.0-fold later breakthrough point and 1.1~2.7-fold higher adsorption capacity than the other dry sorbents.

  • PDF

Molecular Sieve Properties for $CH_4/CO_2$ of Activated Carbon Fibers Prepared by Benzene Deposition (벤젠 증착에 의해 제조된 활성탄소섬유의 $CH_4/CO_2$ 분자체 성질)

  • Moon, Seung-Hyun;Shim, Jae-Woon
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.27 no.6
    • /
    • pp.614-619
    • /
    • 2005
  • The activated carbon fibers of different surface area and pore structures were modified by carbon deposition from the pyrolysis of benzene, in an attempt to obtain carbon molecular sieves of high adsorption capacity and selectivity for the separation of $CO_2/CH_4$ gas mixtures. The ACFs molecular sieves prepared from different temperature and time were tested by the static adsorption of $CO_2$ and $CH_4$ gas, and their pore structures were characterized by the $N_2$ adsorption isotherms. We are able to prepare ACF molecular sieve with good selectivity for $CO_2/CH_4$ separation and showing acceptable adsorption capacities from the change of porosity by carbon deposition of pyrolyzed benzene.