• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.819-821
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• 2002

Photoluminescenc (PL) and low-voltage cathodoluminescence (CL) characteristics of $[xSrTiO_3+(1-x)Li_2TiO_3]:Pr^{3+}$ and $[xSrTiO_3+(1-x)Na_2TiO_3]:Pr^{3+}$ systems were investigated. The red luminescence intensities of these compounds are enhanced remarkably by the incorporation of $Li^+$ or $Na^+$ ion as compared to that of $SrTiO_3:Pr^{3+}$. The enhanced luminescence is speculated to result from both the charge compensation of $Pr^{3+}$ site and oxygen vacancies generated in the lattices by $Li^+$ or $Na^+$ ion.

• Journal of Environmental Science International
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• v.24 no.8
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• pp.1015-1021
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• 2015

In order to establish the design parameters of adsorption for arsenic compounds with hydrotalcite including chlorine ion, the basic properties of adsorption and desorption as well as the oxidation of As (III) were examined in batch tests. The maximum adsorption capacities of arsenite and arsenate were 6.2 mg-As(III)/g and 103 mg-As (V)/g, respectively. Although 80.4% of maximum desorption was shown in 20% NaOH solution, 5~10% of NaOH was recommended considering operating benefits, where the proper condition of the desorption was in the range of 73% to 80%. The most suitable desorption condition was in the combination of NaCl (10~20%) and NaOH (5~10%). Within 2 minutes, As (III) was easily oxidized to As (V) with 0.0001 N KMnO4, where the maximum oxidization ratio was shown to 98.9%.

• Microbiology and Biotechnology Letters
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• v.9 no.2
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• pp.83-89
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• 1981

Several kinds of organic acids, alcohols, aromatic compounds and sugars as carbon sources were tested in order to produce the cell mass of Rhizopus oryzae which is used in part of food processing or organic acid fermentation. Sodium acetate among them was good enough for carbon source as well as glucose under the concentration of one percent. All nitrogenous substances tested such as ammonium, nitrate or organic nitrogen compounds were well used by this strain of Rhizopus oryzae as nitrogen source. Ammonium sulfate among inorganic nitrogen compounds was most utilized as a nitrogen source in glucose or acetate medium. This strain did not require any growth factors such as yeast extract. The following composition of medium was therefore determined in order to produce the cell mass of Rhizopus oryzae: Na-acetate 1 %, (NH$_4$)$_2$SO$_4$ 0.2%, $K_2$HPO$_4$ 0.05%, MgSO$_4$.7$H_2O$ 0.01%, NaCl 0.01% (PH 5.5). The cell wall of mycelium grown in above medium was lysed optimally at pH 6.5 and 5$0^{\circ}C$ by the action of Strepzyme 115-5. On producing protoplast from mycelium by enzymatic action, almost all of the mycelium was damaged after 4hrs of treatment.

• Natural Product Sciences
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• v.11 no.3
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• pp.170-173
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• 2005

Compounds of (+)-5,5'-dimethoxylariciresinol (1) and (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (2) were isolated from an EtOAc extract of the whole plant of Sasa borealis (Hack.) Makino (Gramineae) for the first time in the present investigation. The structures of compounds were identified by analysis of spectral data including 1D- and 2D-NMR spectra as well as by comparison of their data with the published values. These compounds have never been isolated previously from the family Gramineae.

• Journal of the Korean Magnetic Resonance Society
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• v.21 no.4
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• pp.145-151
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• 2017

Rhodiola rosea, also known as gold root or rose root, is a perennial plant in the family of Crassulaceae. The rhizhome of R. rosea has been widely used as a hemostatic, tonic for burns and contusions in traditional Chinese medicine. Recent studies reported its strong antioxidant and adaptogenic properties. In this paper, we attempted to isolate compounds from the methanolic extract of R. rosea rhizomes. Four compounds including one new compound (1), two kaempferol glycosides (3 and 4) were isolated from chloroform and ethyl acetate soluble fraction of R. rosea extract. The structures of 1~4 including relative stereochemistry were determined by MS and NMR analysis.

• Journal of Powder Materials
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• v.1 no.1
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• pp.66-71
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• 1994

Optical microstructures and mechanical properties of Na gas atomized Al-20Si-5Fe alloying powder and its hot extrudates were studied on 3 different types of powder size distribution. This powder showed the size distribution of 10~210 $\mu\textrm{m}$. Also the microstructures of $\alpha$-Al, primary and eutectic Si and needle shaped intermetallic compounds were observed by optical microscope. These needle shaped intermetallic compounds were identified as ${\delta}Al_4FeSi_2$- by XRD and EDX analysis. The ultimate tensile strength(UTS) of these alloy extrudates was increased from 324 to 390 MPa with decreasing powder size range from 120~210 $\mu\textrm{m}$ to 10~64 $\mu\textrm{m}$. A value of Micro-vic-kers hardness was simillar to the result of UTS. These extrudates showed better wear resistance than those of Al-20Si-2X(X : Ni, Cr, Zr), although they are insensitive to the size distribution. These results indicate that the presentation of ${\delta}Al_4FeSi_2$ intermetallic compounds contributed to the wear resistance improvement.

• Natural Product Sciences
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• v.21 no.4
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• pp.293-296
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• 2015

A new L-isoascorbic acid derivative epi-leptosphaerin (1) and two known compounds leptosphaerin (2), and verongamine (3) were isolated from sponges of the orders Verongida and Thorectidae. Compounds 1 and 2 are most likely of sponge-associated fungal origin. In the present study, isolated compounds were investigated for their inhibition of soluble epoxide hydrolase (sEH), which is considered a promising target for the management of pain, inflammation, and comorbidities associated with diabetes. Compound 3, verongamine, displayed weak inhibitory activity against sEH with an $IC_{50}$ value $51.5{\pm}1.0{\mu}M$.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.719-723
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• 2006

Chlororinated bibenzyl compounds (1 and 2) inhibited the growth of the Gram positive bacterium Bacillus subtilis ATCC 19659, (2 mm inhibition zone and 2 mm inhibition zone at $30{\;}{\mu}g/disc$), Candida albicans ATCC 14053, (2 mm inhibition zone and 2 mm inhibition zone at $30{\;}{\mu}g/disc$), and the dermatophytic fungi Trichophyton mentagrophytes ATCC 28185, (3 mm inhibition zone and 7 mm inhibition zone at 30 Ug/disc) and Cladosporium resl'nae ATCC 52833 (1 mm inhibition zone at $30{\;}{\mu}g/disc$).

• Korean Journal of Medicinal Crop Science
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• v.13 no.2
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• pp.80-84
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• 2005

Five known anthraquinones, physcion (1), I-O-methylemodin (2), emodin (3), $physcion-8-O-{\beta},-D-glucopyranoside$ (5), $emodin-8-O-{\beta},-D-glucopyranoside$ (6) and two known stilbenes, trans-resveratrol (4), $trans-resveratrol-3-O-{\beta},-D-glucopyranoside$ (7) were isolated from MeOH extract of Reynoutria sachalinensis (Polygonaceae). All structures were unambiguously established by 1D and 2D NMR and MS data and the compounds were evaluated for their cytotoxicity against L1210, HL-60, BI6F10 tumor cell lines in MTT assay. Among the compounds, trans-resveratrol (4) exhibited significant cytotoxic activity with $IC_{50}$ values of 9.2, 6.7 and $9.8\;{\mu}g/ml$, against the test cell lines respectively, but compounds 1-3 exhibited the moderate cytotoxic activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.87-93
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• 1999

This study was carried out to investigate the effects of nucleic acid related compounds and metal ions on activities of cytidine deaminase from Bacillus subtilis ED 213. The purified cytidine deaminase was weakly inhibited by 1mM GMP, IMP and ATP, but not affected by other nucleic acid related compounds such as CMP and UDP. The apparent Km values for cytidine, deoxycytidine, 5 methylcy tidine, fluorodeoxycytidine, and 5 bromocytidine were calculated to be 6.6$\times$10-4M, 6.0$\times$10-4M, 0.9$\times$10-4M, 0.8$\times$10-4M, and 2.0$\times$10-3M, respectively. The cytidine deaminase was completely inhibited by 1mM Hg2＋, and mildly inhibited over 40% by metal ions such as Na＋ and Fe2＋. However the enzyme activity was activated more than 40% by 1mM Mg2＋.