• Journal of Microbiology and Biotechnology
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• 제11권3호
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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.

• 대한화학회지
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• 제38권6호
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• pp.435-441
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• 1994

3차원 금속 착제, Cd(pn)Ni(CN)4를 host로 하는 포접 화합물을 합성하고, X-선 회절 데이타를 이용한 단결정의 구조해석을 하였다. 결정학적 데이타는 다음과 같다. $[Cd(pn)Ni(CN)_4]{\cdot}0.5(CH_3COCH_3{\cdot}H_2O)$, 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, $D_x=1.81 gcm^{-3}$, $\mu(MoK{\alpha})$ = $28.153cm^{-1}$, T = 297K, 3521개($F_0>3{\sigma}(F_0)$)의 회절 강도에 대한 최종 신뢰도 인자 R = 0.0418이 얻어졌다. 이 포접 화합물은 thiourea 포접 화합물과 유사한 턴넬형의 포접 공간(T-type)을 형성하며, 이런 포접공간 내에 분자당 0.5개의 아세톤과 물분자를 guest로서 받아 들인다. 표제의 포접 화합물은 이미 보고된 바와 같이, 가지달린 유기 guest분자가 host의 기하구조를 T-type으로 이끈다고 하는 host 선택성에 대한 또 하나의 증거가 된다.

• 한국전기전자재료학회논문지
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• 제20권9호
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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.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2009년도 추계학술발표논문집
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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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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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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.

• 한국결정학회지
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• 제10권1호
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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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/$cm^2$.

• 한국전기전자재료학회논문지
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• 제26권9호
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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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• 제23권6호
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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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• 제29권5호
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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.