• Journal of Magnetics
• /
• 제11권4호
• /
• pp.195-207
• /
• 2006

The recently published and new results on design and fabrication of magnetophotonic crystals of different dimensionality are surveyed. Coupling of polarized light to 3D photonic crystals based on synthetic opals was studied in the case of low dielectric contrast. Transmissivity of opals was demonstrated to strongly depend on the propagation direction of light and its polarization. It was shown that in a vicinity of the frequency of a single Bragg resonance in a 3D photonic crystal the incident linearly polarized light excites inside the crystal the TE- and TM-eigen modes which passing through the crystal is influenced by Brags diffraction of electromagnetic field from different (hkl) sets of crystallographic planes. We also measured the faraday effect of opals immersed in a magneto-optically active liquid. It was shown that the behavior of the faraday rotation spectrum of the system of the opal sample and magneto-optically active liquid directly interrelates with transmittance anisotropy of the opal sample. The photonic band structure, transmittance and Faraday rotation of the light in three-dimensional magnetophotonic crystals of simple cubic and face centered cubic lattices formed from magneto-optically active spheres where studied by the layer Korringa-Kohn-Rostoker method. We found that a photonic band structure is most significantly altered by the magneto-optical activity of spheres for the high-symmetry directions where the degeneracies between TE and TM polarized modes for the corresponding non-magnetic photonic crystals exist. The significant enhancement of the Faraday rotation appears for these directions in the proximity of the band edges, because of the slowing down of the light. New approaches for one-dimensional magnetophotonic crystals fabrication optimized for the magneto-optical Faraday effect enhancement are proposed and realized. One-dimensional magnetophotonic crystals utilizing the second and the third photonic band gaps optimized for the Faraday effect enhancement have been successfully fabricated. Additionally, magnetophotonic crystals consist of a stack of ferrimagnetic Bi-substituted yttrium-iron garnet layers alternated with dielectric silicon oxide layers of the same optical thickness. High refractive index difference provides the strong spatial localization of the electromagnetic field with the wavelength corresponding to the long-wavelength edge of the photonic band gap.

• 대한화학회지
• /
• 제39권2호
• /
• pp.118-122
• /
• 1995

• Bulletin of the Korean Chemical Society
• /
• 제27권5호
• /
• pp.755-758
• /
• 2006

• 한국고분자학회:학술대회논문집
• /
• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
• /
• pp.27-28
• /
• 2006

Chromatographic separation of enantiomers by high-performance liquidchromatography (HPLC) has considerably advanced in the past two, and many optically active polymers have been developed to be usedaschiral stationary phases (CSP). Among many CSPs, cellulose-andamylose-based CSPs are most attractive from the viewpoints of theirwide applicability and easy availability. The polysaccharides are readily modified to ester and carbamates. The derivatives have been used as CSPs after being coated on macroporus silica gel. Here, the CSPs based on phenylcarbamate derivatives of these two polysaccharides will be mainly discussed. The immobilization of the derivatives on silica gel will also be discussed.

• 통합자연과학논문집
• /
• 제8권2호
• /
• pp.107-110
• /
• 2015

Amino acid-catalyzed directed asymmetric aldol reactions showed enhanced enantioselectivity when conducted in ionic liquids. Optically active products were afforded in better yields (up to 23% higher) and enantiomeric excess (up to 21% higher) in ionic liquids than in conventional organic solvents.

• Bulletin of the Korean Chemical Society
• /
• 제30권6호
• /
• pp.1317-1324
• /
• 2009

Asymmetric transfer hydrogenation of α-functionalized arylketones has been studied. The chiral Rh-catalyst effectively performed in transfer hydrogenation of $\alpha$-mesyloxyketones with an azeotropic mixture of formic acid/triethylamine to produce optically active 1-arylethandiols with excellent enantioselectivity.

• Archives of Pharmacal Research
• /
• 제29권5호
• /
• pp.369-374
• /
• 2006

An efficient method for the synthesis of optically active 2-substituted 2,3-dihydro-4-quinolones has been developed. The key features include the introduction of a chiral side chain and the construction of quinolone skeleton by Mitsunobu alkylation and hydroarylation, respectively.

• Bulletin of the Korean Chemical Society
• /
• 제7권6호
• /
• pp.444-447
• /
• 1986

Optically active (R,Z)-(-)-5-tetradecen-4-olide, the pheromone of Popillia japonica Newman was synthesized from (R)-2,3-O-isopropylideneglyceraldehyde as starting material. The biological activity test of the synthetic pheromone as attractant for the male Japanese beetle was tested in Korea.

• Bulletin of the Korean Chemical Society
• /
• 제10권6호
• /
• pp.559-563
• /
• 1989

Optically active (R)- and (S)-2-benzyloxy-1-butanol have been prepared by a previously described asymmetric synthesis based on a chiral oxathiane and have been converted into (R)-(+)-4-hexanolide, a component of the pheromone secreted by the female of the dermestid beetle, and its enantiomer.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
• /
• pp.243.1-243.1
• /
• 2003

Extensive efforts in the search of therapeutically useful carbocyclic nucleosides have resulted in a wealth of their synthetic methodologies in racemic and optically active forms. The classical one-directional methods such as linear synthesis and convergent synthesis are the approaches most frequently seen in the literature for the preparation of carbocyclic nucleosides, and their advantages and limitations are well known. (omitted)