• Korean Journal of Materials Research
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• v.26 no.11
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• pp.598-603
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• 2016

The recent development of electro-optic devices and anticorrosion media has led to the necessity to investigate infrared optical systems with solid-solid interfaces of materials that often have the characteristic of amorphousness. One of the most promising classes of materials for those purposes seems to be the chalcogenide glasses. Chalcogenide glasses, based on the Ge-Sb-Se system, have drawn a great deal of attention because of their use in preparing optical lenses and transparent fibers in the range of 3~12 um. In this study, amorphous Ge-Sb-Se chalcogenide for application in an infrared optical product design and manufacture was prepared by a standard melt-quenching technique. The results of the structural, optical and surface roughness analysis of high purity Ge-Sb-Se chalcogenide glasses are reported after various annealing processes.

• Composites Research
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• v.28 no.2
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• pp.40-45
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• 2015

The purpose of the present work was to preparation and study of full biodegradable Eco-friendly bio-composites by using renewable resources. In this study, wheat protein isolate (WPI) films were formed by cross linking with resorcinol through solution casting method for packaging applications. By varying the resorcinol content (10, 20, 30, 40, and 50 wt %), its effect on mechanical properties of the wheat protein isolate film was measured. The addition of 20% resorcinol led to an overall increase in the tensile strength from 5.2 to 18.6 MPa and modulus increase from 780 to 1132 MPa than WPI films. The % elongation was increased from 2.8 to 9.05 when compared to unmodified WPI film. A thermal phase transition of the prepared WPI was assessed by means of DSC. FTIR is evident that the characteristic WPI spectral IR bands shifted on cross-linking with resorcinol.

• Journal of the Korean Applied Science and Technology
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• v.22 no.4
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• pp.355-361
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• 2005

The physical characteristics of polyurethane were examined by SEM, FT-IR tensile strength and mole % [NCO/OH]. Growing concerns in the environment-friendly architecture and public works have led to the development of solvent-free formulations that can be cured and foamed in air. Compared with general packing materials, this resin is much stronger in intensity and much longer in durability. Polyurethane foam resins were mainly composed of polyol, MDI, silicone surfactant, fillers, catalyst and blowing agent. The rigid foam of polyurethane in mechanical characteristics were due to chain extender and the increase of mole % [NCO/OH]. The change in the microstructure of polyurethane should be taken into account when considering the process of construction and durability through the polyurethane polymer resin in lots of industries.

• Journal of Society of Preventive Korean Medicine
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• v.9 no.1
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• pp.135-141
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• 2005

Bioassay-directed fractionation of the dired roots of Sophorae Radix led to the isolation of Sophoraflavanone G. Their structures were elucidated using 1H-NMR, 13C-NMR, UV, IR and mass spectral ananlyses. These compounds exhibited a moderate antimicrobial activities against Streptococcus gordonii, Actinobacillus actinomycetemoomitans and Porphylomonas gingivalis.

• Natural Product Sciences
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• v.11 no.2
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• pp.85-88
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• 2005

The methanolic extract from the seeds of Arctium lappa was found to inhibit the LPS-induced nitric oxide (NO) production in murine macrophage RAW264.7 cells. Bioassay-guided fractionation of a methylene chloride soluble fraction led to the isolation of three lignan compounds, arctiin (1), arctigenin (2), and lappaol B (3). Their structures were elucidated by UV, IR, MS, and NMR data, as well as by comparison with those of the literatures. Arctigenin (2) and lappaol B (3) had an iNOS inhibitory activity with $IC_{50}$ values of 12.5 and $25.9\;{\mu}M$, respectively.

• Natural Product Sciences
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• v.21 no.4
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• pp.273-277
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• 2015

Comprehensive chemical analysis of extracts and fractions of marine actinomycete strains led to the discovery of a new minor secondary metabolite, salternamide E (1), from a saltern-derived halophilic Streptomyces strain. The planar structure of salternamide E (1) was elucidated by a combinational analysis of spectroscopic data including NMR, MS, UV, and IR. The absolute configuration of salternamide E (1) was determined by circular dichroism spectroscopic analysis. Salternamide E displayed weak cytotoxicity against various human carcinoma cell lines.

• Natural Product Sciences
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• v.17 no.3
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• pp.181-182
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• 2011

Phytochemical investigation of Lycium chinense fruits led to isolation of a new pyrrole compound. The structure of this compound was confirmed as a 5-methoxymethyl-lH-pyrrole-2-carbaaldehyde, a new natural product, by interpretation of 1D ($^1H$, $^{13}C$) and 2D (HMQC, HMBC) spectroscopic data along with HRMS and IR spectroscopic data.

• Korean Journal of Materials Research
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• v.5 no.5
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• pp.620-624
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• 1995

To study the acid and base properties of chemical-treated natural zeolite, FT-IR analysis was performed by the adsorption of pyridne and pyrrole and thermo-gravimetric analysis was done by the adsorption of NH$_{3}$. These solid catalysts have two acid sites, which are related to the Bronsted and Lewis acid sites, respectively. HIC-treatment led to the increased acidity and the maintained basicity.Acidity of NaHO-treatment samples also increased with thr NaOH-treatment but basicity decreased. The p-xylene selectivity on the chemical-treatment zelite was higher than that on the untreated zeolite.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.145-149
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• 2007

Saussurea Radix, the dried roots of Saussurea lappa Clark (Compositae), has been used in oriental traditional medicine for aromatic stomachic. Present study was carried out for the anticancer effect of Saussurea Radix. Bioassay-directed fractionation of Saussurea Radix led to the isolation of two sesquiterpenes, dehydrocostuslactone (1) and costunolide (2). The structures of 1 and 2 were elucidated by spectral methods (MS, IR, $^1$H and $^{13}$C NMR). These compounds showed a potent cell proliferation activity against human breast cancer cell MCF-7 and MDA-MB-453.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.441-445
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• 2005

Tripterygium regelii has been used as an oriental medicine, especially antiparasitic, anti-inflammatory and detoxifying agents in East asia. During our research to develop new antitumor agents from natural products, MeOH ext. and CH2Cl2 ext. of Tripterygium regelii showed the potent antitumor activity. In order to purify active compounds from Tripterygium regelii, activity-guided fractionation was carried out. Silica gel and RP-18 column chromatography for the active fraction led to the isolation of two compounds and their antitumor activities were studied. Those two compounds didn't show potent antitumor activity against human tumor cell lines. The structure of two compounds were determined by $^1H-NMR$, $^{13}C-NMR$, DEPT, $^1H-^{13}C$ COSY and IR spectrum. Compound I and Compound II were turned out to be Celastrol, and ${\beta}-sitosteryl-3-o-{\beta}-D-glucopyranoside$ respectively.