• 발명특허
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• v.15 no.6 s.172
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• pp.25-31
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• 1990

• 발명특허
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• v.6 no.12 s.70
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• pp.30-31
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• 1981

• Journal of the Korean Chemical Society
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• v.61 no.1
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• pp.16-24
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• 2017

The adsorption of various atmospheric harmful gases ($CO_x$, $NO_x$, $SO_x$) on graphene-like boron nitride(BN) and aluminum nitride(AlN) sheets was theoretically investigated using density functional theory (DFT) and MP2 methods. The structures were fully optimized at the $B3LYP/6-31G^{**}$ and $CAM-B3LYP/6-31G^{**}$ levels of theory and confirmed to be a local minimum by the calculation of the harmonic vibrational frequencies. The MP2 single-point binding energies were computed at the $CAM-B3LYP/6-31G^{**}$ optimized geometries. Also the zero-point vibrational energy (ZPVE) and 50%-basis set superposition error (BSSE) corrections were included. The adsorptions of gases on the BN sheet were predicted to be a physisorption process and the adsorptions of gases on the AlN sheet were predicted to be a physisorption process for $CO_x$ and $NO_x$ but to be a chemisorption process for $SO_x$.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.521-529
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• 2009

Molecular structures of the various conformers for the 1,3-dimethoxy-p-tert-butylthiacalix[4] crown-5-ether (3) were optimized by using DFT B3LYP/6 - 31 + G(d,p) and mPW1PW91/6 - 31 + G(d,p) (hybrid HF-DF) calculation methods. We have analyzed the energy differences and structures of eight in/out orientations (cone_oo, cone_oi, pc_oo, pc_io, pc_oi, pc_ii, 13a_oo, 13a_io) of two methoxy groups in three major conformations (cone, partial-cone and 1,3-alternate). The 13a_oo (out-out orientation of the 1,3-alternate conformer) is calculated to be the most stable among eight different conformations of 3, and in accord with the experimental result. The ordering of relative stability resulted from the mPW1PW91/6 - 31 + G(d,p) calculation method is following: 13a_oo > 13a_io$\sim$pc_io$\sim$cone_oo > cone_oi$\sim$pc_oo$\sim$pc_oi > pc_ii.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.479-489
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• 2011

This study was carried out to propose AUI(Advanced Urbanized Index), ADI(Advanced Disturbed Index) and TEI(Total Environmental Index) and to understand the ecological characteristics of naturalized plants by objective and systematic analysis about naturalized plants distributed in Gyeryong-si, Chungcheongnam-do, Korea. The numbers of naturalized plants identified in this site were 47 taxa; 15 families, 35 genera and 47 species. The invasive alien plants were 5 taxa; Aster pilosus Willd., Rumex acetocella L., Sicyos angulatus L., Amborisa trifida L., and A. artemisiaefolia L. In the results of analysis by administrative district, Shindoan-myeon was 33 taxa, Eomsa-myeon 29 taxa, Duma 31 taxa and Geumam-dong 18 taxa. In an analysis of life forms, there were 6 taxa of chamaiphytes, 8 taxa of hemicryptophytes, 2 taxa of geophytes and 31 taxa of therophytes. In the results of analysing environmental indices, the range of UI was 6.5~11.8%, AUI 0.3~5.3%, DI 18.2~36.4%, ADI 0.9~16.4% and TEI 0.6~10.9%. The AUI, ADI and TEI of whole Gyeryong-si were 16.8%, 45.5% and 31.2%.

• Journal of Life Science
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• v.31 no.5
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• pp.496-501
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• 2021

In this study, the marine agar-degrading bacterium Pseudoalteromonas sp. JH-1 was isolated, and its growth and agarase properties were investigated. Seawater was collected from the offshore of the Yonggung Temple in Busan, and agar-degrading bacteria were isolated and cultured with marine agar medium. The bacterium Pseudoalteromonas sp. JH-1 was isolated through 16S rRNA gene sequencing. The extracellularly secreted enzyme was obtained from the culture broth of Pseudoalteromonas sp. JH-1 and was used to characterize its agarase. The extracellular agarase exhibited a maximum activity of 116.6 U/l at 50℃ and pH 6.0 of 20 mM Tris-HCl buffer. Relative activities were 31, 59, 94, 100, 45, and 31% at 20, 30, 40, 50, 60, and 70℃, respectively. Relative activities were 49, 85, 100, 86, 81, and 67% at pH 4, 5, 6, 7, 8, and 9, respectively. Residual activity was more than 85% after exposure at 20, 30, and 40℃ for 2 hr, and more than 82% after exposure at 50℃ for 2 hr. Zymogram analysis confirmed that Pseudoalteromonas sp. JH-1 produced at least two agarases of 55 and 97 kDa. As the products of α-agarase and β-agarase have antioxidation, antitumor, skin-whitening, macrophage activation, and prebiotic effects, further studies are needed on the agarase of Pseudoalteromonas sp. JH-1.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.181-187
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• 2010

Purpose: To determine clinical results for arthroscopic repair of a full-thickness rotator cuff tear using a suture bridge technique. Materials and Methods: Between November, 2007 and October, 2008, we evaluated 90 cases of arthroscopic middle, large rotator tear cuff repair. The mean follow-up period was 15 months (range, 12-23 months). Forty-three cases had medium-sized tears; 47 cases had large-sized tears. At the preoperative stage and again at last follow-up, functional results were assessed by the KSS, ASES, UCLA and the PVAS (Pain visual analogue score). Results: Pain score improved from 2.56 preoperatively to 0.96 at final follow-up; movement scores improved from 6.94 to 1.70. At. final follow-up, the average UCLA score improved from 17.08 to 31.17 with 31 excellent (34%), 49 good (54%) and 10 poor results (12%). The final UCLA score was 31.47 in the group less than 60 years of age and 30.69 in the group over 61 years of age (p=0.344). The UCLA score was 31.23 in those with medium-sized tears and 31.11 in those with large-sized tears (p=0.924). The UCLA score was 31.10 in non-trauma patients and 31.23 in trauma patients (p=0.929). Conclusion: Arthroscopic repair of a full-thickness rotator cuff tear using a suture bridge technique can produce excellent clinical results. These outcomes are not affected by age or trauma history.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.122-132
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• 1998

SB-31 which contains Pursatilla, Licoris and Ginseng extracts was recently proved as an anticancer agent. In a preclinical effort to be applied this drug to human, pharmacokinetics of SB-31 was carried out in rats and rabbits. Glycyrrhizin(GZ), a saponin of Licoris was used as a standard ingradient for the pharmacokinetics of SB-31. The rat's blood, bile and urine samples were serially collected in femoral vein, common bile duct and bladder, respectively, after bolus i.v. injection at a dose of 1 or 1/5 ampul/rat and rabbit's blood samples from the marginal ear vein at a dose of 1 or 3 amp./rabbit. GZ and glycyrrhetic acid(GA), a major metabolite of GZ in the physiological samples were analysed by HPLC with UV detection. The decline of GZ in plasma concentration was generally biexponential at each dose. GZ was almost completely recovered in bile within 18 hour. GA wasn't detected in the samples with UV detector. In the rat, Vss and Kel at a dose of 1 and 1/5 ampul of SB-31 were $98.06\pm6.07\;ml,\;0.33\pm0.05\;hr^{-1}\;and\;65.46\pm11.19\;ml,\;0.68\pm0.25\;hr^{-1}$, respectively. Those in rabbits at a dose of 3 and 1 ampul of SB-31 were $235.24\pm30.72\;ml,\;0.13\pm0.36\;hr^{-1}\;and\;341.32\pm28.58\;ml,\;0.27\pm0.04\;hr^{-1}$, respectively. 'WinNonlin' was utilized for the compartmental analysis. A two-compartment model was chosen as the most appropriate pbarmaco-kinetic model. The data were best described by using a weighting factor of $1/y^2$. To evaluate the effect of SB-31 on cardiovascular system, serially diluted SB-31 was directly injected into coronary artery in the isolated perfused rat heart and the effect of PSF, PSH, saponins of Pursatilla, and SB-31 on PT, APTT of healthy human plasma was examined. Except the positive inotropic effect of ten times diluted solution of SB-31, there was no significant effect on LVDP, (- dp/dt)/(+dp/dt), heart rate and coronary flow in comparision with that of vehicle. SB-31 had no effect on PT but slightly delayed APTT about $6.9{\sim}11.5\%$. There was no significant effect of PSF and PSH on PT & APTT. Conclusively, SB-31 did not show any notable toxic effects on cardiovascular system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.395-398
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• 2009

The purpose of this paper is to investigate the effect of annealing treatment on cold formability of magnesium alloy sheet AZ31. The AZ31 sheets with three different thickness (1.0t, 1.6t, 2.0t) were annealed at three different temperatures ($345^{\circ}C$, $400^{\circ}C$ and $450^{\circ}C$). The mechanical properties and microstructure evolution of the annealed AZ31 were examined as well as limit dome height (LDH) and compared with those of as received one. The cold formability was enhanced but the strength was deteriorated by the annealing treatment.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2514-2518
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• 2010

A very simple synthetic route of a novel SATE prodrug type of 6'-fluoro-6'-methyl-5'-noradeonosine carbocyclic nucleoside phosphonic acid is described. The key fluorinated alcohol intermediate 7 was prepared from the epoxide intermediate 6a via selective ring-opening of epoxide. Coupling of 7 with $N^6$-bis-Boc-adenine under a Mitsunobu reaction followed by phosphonation and deprotection afforded the carbocyclic phosphonic acid. The chemical stability of the bis(SATE) derivative 13 was measured at neutral (pH 7.2) and slightly acidic (Milli-Q water, pH 5.5) pH. The antiviral activity test of the SATE prodrug 13 and its parent nucleoside phosphonic acid 11 were evaluated against HIV-1.