• Korean Chemical Engineering Research
• /
• v.45 no.5
• /
• pp.487-492
• /
• 2007

Using the selective host-guest inclusion of $G_2$[naphthalene disulfonate], the structural isomers of 1,2-dibromobenzene and 1,3-dibromobenzene were separated. As such, 1,3-dibromobenzene was selectively included as guest into the host framework in mixture isomers over 30% fraction of 1,3- dibromobenzene ($X_{1,3-DBB}=0.3$) whereas 1,2-dibromobenzene as guest was selective to the inclusion below $X_{1,3-DBB}=0.3$. This was due to the selectivity of host framework toward the guest molecules playing a role of template to the host framework. From the powder pattern XRD of inclusion compounds crystallized in pure isomer and mixture solutions, the template roles of guest molecules to the host framework were confirmed. Using the DSC, it was found that the more energy was required to release 1,3-dibromobenzene of guest from the host framework than 1,2-dibromobenzene due to the higher thermal stability. The thermal stability of the $G_2NDS$-1,3-dibromobenzene inclusion compound was consistent with the high selectivity of 1,3- dibromobenzene to the host framework in broad range of fraction in the isomer mixture

• Journal of the Korean Chemical Society
• /
• v.40 no.7
• /
• pp.509-514
• /
• 1996

The three-dimensional metal complex inclusion compound $Cd(pn)Ni(CN)_4{\cdot}0.5NO_2C_6H_5$(pn: 1,2-diaminopropane=propylenediamine) crystallizes in the orthorhombic space group, $Pn2_1$a, (a=13.868(5), b=26.591(4), c=7.840(1)${\AA}$, V=2891(1)${\AA}^3$, Z=4), R=0.054 for 2800 independent reflections. The host structure of the inclusion compound appears the same one(T-type) of inclusion compound with branched aliphatic-guest molecule. The nitrobenzeneguest molecule attains the stable position in the nodal channel of T-type by placing the polar nitro group between the pn-amino groups at the node and the bulky aromatic ring in the antinodal zone of the channel. The substituted aromatic guest molecule is accommodated in the host structure of metal complex $Cd(pn)Ni(CN)_4$ with channel cavity.

• Bulletin of the Korean Chemical Society
• /
• v.22 no.11
• /
• pp.1248-1254
• /
• 2001

The conformations and energies of p-tert-butylcalix[4]crown-6-ether (1) and its alkyl ammonium complexes have been calculated by ab initio HF/6-31G quantum mechanics method. The cone conformation was found to be most stable for free host 1. We hav e determined the binding site of these host-guest complexes focusing on the crown-6-ether or p-tert-butylcalix[4]arene pocket of the cone conformation of host molecule 1. The primary binding site of host 1 for the recognition of alkyl ammonium guests was confirmed to be the central part of the crown moiety of cone conformation. The complexation energy calculations revealed that the ammonium cation without alkyl group showed the highest complexation efficiency when combined with host 1, that is in satisfactory agreement with the experimental results.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.15 no.1
• /
• pp.51-62
• /
• 1989

Inclusion complex formation of octyldimethl p-aminobenzoate with $\beta$-cyclodextrin in aqueous solution and in the solid state was studied by the solubility method, spectroscopic(UV, FT-lR) and X -ray diffractometry. The solid complex of octyldimethy p-aminobenzoate with $\beta$-cyclodextrin was obtained in molar ratio of 1 : 2(guest/host). A spatial relationship between host and guest molecule was clearly reflected in the magnitude of the apparent stability constant (K') and in the stoichiometry of the inclusion complex. Furthermore, a typical type Bs phase-solubility diagram was obtained for octyldimethyl p-aminobenzoate and p -cyclodextrin in water at $25^{\circ}C$. The results indicated that the solubility of the guest molecule was higher by the formation of $\beta$-cyclodextrin inclusion complex.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.05a
• /
• pp.150.2-150.2
• /
• 2011

Unlike non-ionic clathrate hydrates stably formed by van der Waals interaction between a guest molecule and a surrounding host framework, ionic clathrate hydrates are stabilized by ionic interaction between an ionic guest molecule and the host water-framework. Here, we firstly described the stable entrapment of the superoxide ions in ${\gamma}$-irradiated $Me_4NOH+O_2$ hydrate. Owing to peculiar direct guest-guest ionic interaction, the lattice structure of ${\gamma}$-irradiated $Me_4NOH+O_2$ hydrate shows significant change of lattice contraction behavior even at relatively high temperature(120K). Particularly, we note that ionic-induced dimensional change is much greater than thermal-induced change. Such findings are expected to provide useful information for a better understanding of unrevealed nature of clathrate hydrate fields.

• Journal of the Korean Applied Science and Technology
• /
• v.6 no.1
• /
• pp.59-66
• /
• 1989

Inclusion complex formation of octyldimethyl p-aminobenzoate with ${\beta}-cyclodextrin$in aqueous solution and in the solid state was studied by the solubility method, spectroscopic (UV, FT-IR) and X-ray diffractornetry. The solid complex of octyldimethyl p-aminobenzoate with ${\beta}-cyclodextrin$ was obtained in molar ratio of 1:2 (guest/host). A spatial relationship between host and guest molecule was clearly reflected in the magnitude of the apparent stability constant (K') and in the stoichiometry of the inclusion complex. Furthermore, a typical type Bs phase-solubility diagram was obtained for octyldimethyl p-aminobenzoate and ${\beta}-cyclodextrin$ in water at $25^{\circ}C$. The results indicated that the solubility of the guest molecule was higher by the formation of ${\beta}-cyclodextrin$ inclusion complex.

• Bulletin of the Korean Chemical Society
• /
• v.18 no.5
• /
• pp.473-474
• /
• 1997

• Journal of Periodontal and Implant Science
• /
• v.26 no.3
• /
• pp.655-668
• /
• 1996

The change in vascular adhesion molecule expression and number of infiltrating leukocytes were investigated irnmunohistochemically in clinically healthy and inflammed gingiva. Monoclonal antibodies to ICAM-1, VCAM-1 and E-cadherin were used to identify positive vessels and leukocyte within gingival biopsies. 10 healthy gingiva and 30 inflammed gingiva was resected by clinical crown lengthening and modified Widman flap operation, respectively. Leukocyte entry into tissues at sites of inflammation is controlled by the interaction between adhesion molecule and endothelium. Because of rapid and severe destructive periodontal disease that is remarkable leukocyte adhesion deficiency, it is very important to unerdstand the mechanism of host defence against periodontal disease. The purpose of this investigation was the characterization of the presence and distribution of the adhesion molecule(ICAM-1, VCAM-1 and Evcadherin) in inflammatory gingival tissues compared to clinically healthy gingiva. The results were as followed; 1. ICAM-1 was distributed on basal layer, endothelium and mononuclear cells 10 healthy gingiva but inflammed gingiva was observed stronger stain than healthy gingiva. 2. Rare expression was observed in both group but few positive VCAM-1 cells were investigated in inflammatory gingival tissues 3. E-cadherin was expressed in only epithelium and reduced expression was observed in inflammatory gingival tissues. ICAM-1, VCAM-1 showed more expression in inflammatory tissues compared to healthy gingiva. Conversely, E-cadherin revealed a opposite result. These finding demonstrate a characteristic distribution and degree of adhesion molecule in healthy and inflammatory gingival tissues. But it is suggested that more detail study be progressive associated with leukocyte adhesion molecule to determine characterization of periodontal disease.

• Mass Spectrometry Letters
• /
• v.6 no.1
• /
• pp.17-20
• /
• 2015

Sesamin, one of the lignans in sesame seed, was a labile compound in MS and it was reported that the protonated molecule of sesamin decomposed easily in ES ionization process and it cannot be detected (G. Yan, et al., Rapid Commun Mass Spectrom. 2007, 21, 3613-3620). To protect labile compounds, an amino-cyclodextrin (NCyD) was added to the sample to promote the host-guest interaction complex in ESI-MS. As a result, sesamin was ionized as the NCyD-sesamin-NCyD (1:2) complex without undesired decomposition, suggesting that the amino-CyDs assist the ionization of the labile molecules capped with CyDs by host-guest interaction and these compounds were ionized without their decomposition, those are like amino-CyD complex-assisted ionization. The amino-CyD complexes of sesamin and sesamolin were also analyzed by their ion-mobility MS.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.767-770
• /
• 2009

We synthesized a spirobenzofluorene type phosphine oxide (SPPO2) as a new triplet host and an universal electron transport material for phosphorescent organic light-emitting diodes(PHOLEDs). Red PHOLEDs with the SPPO2 host material showed a high quantum efficiency of 14.3 % with a current efficiency of 20.4 cd/A. In addition, the SPPO2 could be applied as an electron transport material which can be matched with any host material due to the lowest unoccupied molecular orbital of 2.4 eV. Electron injection from a cathode to the SPPO2 electron transport layer was better than common electron transport materials. In particular, the SPPO2 was effective as the electron transport material in blue PHOLEDs and the quantum efficiency was more than doubled and driving voltage was lowered by more than 3 V using the SPPO2 instead of common electron transport material.