• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.463-468
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• 2001

Cyclosophoraoses are a class of unbranced cyclic-(1longrightarrow2)-${\beta}$-D-glucans found in the Rhizobium species. Their unique cyclic structures and high solubility make them potent for inclusion complexation as a host for an insoluble guest molecule. A family of neutral cyclosophoraoses (DP 17-27) isolated from Rhizobium meliloti 2011 was used as a host for inclusion complexation with an insoluble guest drug, indomethacin. A high performance liquid chromatographic analysis indicated that the inclusion complexation of cyclosophoraoses greatly ehanced the solubility of indomethacin compared with ${\beta}$-cyclodextrin. The estimated value of the association constant of the complex in water for $\beta$-cyclodextrin and cyclosophoraoses was $523M^{-1} and 17,570M^{-1}$, respectively. NMR spectroscopy showed that the inclusion complex was characterized by the interaction of the indole ring moiety of indomethacin with the cavity of cyclosophoraoses.

• Journal of the Korean Chemical Society
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• v.38 no.6
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• pp.435-441
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• 1994

The inclusion compound constituted with three-dimensional metal-complex $Cd(pn)Ni(CN)_4$ has been prepared and determined the crystal structure from single crystal X-ray diffraction data. Crystal data are as follows: $[Cd(pn)Ni(CN)_4]{\cdot}0.5(CH_3COCH_3{\cdot}H_2O)$, Fw = 387.35, Orthorhombic, $Pn2_1a$, a = 13.950(3) $\AA$, b = 26.713(7) $\AA$, c = 7.628(1) $\AA$, V = 2843(1) $\AA^3$, Z = 4, $D_x=1.81 gcm^{-3}$, $\mu(MoK{\alpha})$ = $28.153 cm^{-1}$, T = 297K, final R = 0.0418 for 3521($F_0>3{\sigma}(F_0)$). The metal-complex host provides tunnel cavity, similar to thiourea inclusion compounds, accommodated guest molecules $(=CH_3COCH_3\;and\;$H_2O).$ The stoichiometric host: guest ratio is 0.5. The title inclusion compound reveals another evidence for the host-selectivity, that is, the branched aliphatic guest molecule leads T-type host structure.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.9
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• pp.802-807
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• 2007

We have developed red phosphorescent top emission organic light-emitting diodes with transparent metal cathodes deposited by using thermal evaporation technique. Phosphorescent guest molecule, BtpIr(acac), was doped in host CBP for the red phosphorescent emission, Ca/Ag, Ba/Ag, and Mg/Ag double layers were used as cathode materials of top emission devices, which were composed of glass/Ni/2TNATA(15 nm)/${\alpha}$-NPD(35 nm)/CBP:BtpIr(acac)(40 nm, 10%)/BCP(5 nm)/$Alq_3$(5 nm)/cathodes. The optical transparencies of these metal cathodes strongly depend on underlying Ca, Ba, and Mg layers. These layers also strongly affect the electrical conduction and emission properties of the red phosphorescent top emission devices.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.682-684
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• 2009

본 논문에서는 해수 중에 존재하는 염분을 제거하기 위하여 가스하이드레이트 형성 원리를 이용하였다. 하이드레이트 형성을 위한 guest molecule는 이산화탄소를 사용하였으며, host moelcule로는 3.5% NaCl 물을 사용하였다. 염수에 강한 반응기를 만들기 위하여 스테인레스 강에 epoxy 수지를 코팅하여 실험을 수행하였다. 실험한 결과 70% 이상의 염제거율을 얻을 수 있었으며, 2단 공정이나 3단 공정을 적용할 경우 더욱 높은 염제거율을 얻을 수 있을 것이라고 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.146.2-146.2
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• 2011

Molecular behaviors and crystal structures of the binary hydrates of $CH_4$ and ethanol were identified by means of 13C solid-state NMR and powder XRD methods at various concentrations of ethanol. In addition, NMR peak areas were used to calculate cage occupancies for both guest species. Obtained results showed that more $CH_4$ molecules are captured into hydrate phase per unit mass of ethanol molecules because $CH_4$ molecule can occupy sII large cages more, and pure $CH_4$ hydrate can form more as well at lower ethanol concentrations. Even though tuning phenomenon was already reported for some aqueous hydrate promoters such as THF, aqueous ethanol solutions are found to play the same tuning role in the binary clathrate hydrates in this study.

• Korean Journal of Crystallography
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• v.10 no.1
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• pp.66-70
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• 1999

The calix[4]arene molecule adopting the 1,3-alternate conformation forms a square cavity, and two pair phenyl rings lying above and below a least-square plane defined by the four bridging methylene groups in the calix[4]arene are widened upwards and downwards, respectively, from central axis, which leads to O1-O4=4.064 and O2-O3=3.864 . Two propyloxy groups are stabilized with all trans conformations, but the rather short azacrown ether chain with two oxygen atoms includes cis/trans conformations with O1-C35=2.906 . Therefore the cavity does not seem to be big enough to form a host-guest complex.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.154-154
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• 2010

We have developed transparent OLED with green phosphorescent doped layer using transparent metal cathode deposited by thermal evaporation technique. Phosphorescent guest molecule, $Ir(ppy)_3$, was doped in host mCP for the green phosphorescent emission. Ca/Ag double layers were used as a cathode material of transparent OLED. The turn-on voltage of OLED was 5.2 V. The highest efficiency of the device reachs to 31 cd/A at 2 mA/$cm^2$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.9
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• pp.682-685
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• 2013

We have fabricated blue phosphorescent organic light-emitting devices (OLEDs) on a plastic substrate. The solution coated poly (9-vinylcarbazole) (PVK) host doped with Bis (3,5-difluoro-2-(2-pyridyl)phenyl_(2-carboxypyridyl)irdium(III) (FIrPic) guest molecules was used as an hole transporting emission layer. The device structure was ITO/PVK:FIrpic (50 nm, xwt%)/TAZ 50 nm)/LiF (0.5 nm)/Al (100 nm). The concentration of FIrpic molecule was varied from 1 wt% to 10 wt%. The OLED on plastic substrate exhibited maximum current efficiency of 18 cd/A with 5 wt% FIrpic molecules were doped into the PVK layer.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.891-896
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• 2002

The structures and energies of p-tert-butylcalix[4]crown-6-ether(1) in various conformers and their alkyl ammonium complexes have been calculated by ab initio HF/6-31G quantum mechanics method. We have tried to obtain the relative affinity of partial-cone and 1,3-alternate conformers of 1 for alkyl ammonium guests by comparison with its cone-shaped analogue. We have also calculated the relative complexation efficiency of these host-guest complexes focusing on the binding sites of $crown-\sigma-enther$ moiety or benzene-rings pocket of the host molecule 1. These calculations revealed that the crown moiey has better complexation efficiency than upper rim part of calyx[4]arene that is in similar trend to the cone-shaped complexes.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.953-958
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• 2008

A novel anthraquinone diamino-bridged bis($\beta$ -cyclodextrin) 2 was synthesized. The inclusion complexation behaviors of the native $\beta$ -cyclodextrin 1 and the novel bis($\beta$ -cyclodextrin) 2 with guests, such as acridine red (AR), neutral red (NR), ammonium 8-anilino-1-naphthalenesulfonate (ANS), sodium 2-(p-toluidinyl) naphthalenesulfonate (TNS) and rhodamine B (RhB) were investigation by fluorescence, circular dichroism and 2D NMR spectroscopy. The spectral titrations were performed in phosphate buffer (pH 7.20) at 25 ${^{\circ}C}$ to give the complex stability constants (Ks) and Gibbs free energy changes (−${\Delta}G^0$) for the stoichiometric 1:1 inclusion complexation of host 1 and 2 with guests. The results indicated that the novel bis($\beta$ -cyclodextrin) 2 greatly enhanced the original binding affinity of the native $\beta$ -cyclodextrin 1. Typically, bis($\beta$ -cyclodextrin) 2 showed the highest binding constant towards ANS up to 34.8 times higher than that of 1. The 2D NMR spectra of bis($\beta$ -cyclodextrin) 2 with RhB and TNS were performed to confirm the binding mode. The increased binding affinity and molecular selectivity of guests by bis($\beta$ -cyclodextrin) 2 were discussed from the viewpoint of the size/shape-fit concept and multipoint recognition mechanism.