• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.178.1-178.1
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• 2011

DME is generally expected to be used as a promising clean alternative fuel to diesel fuel. DME is not natural product but a synthetic product that is produced either through the dehydration of methanol or a direct synthetic from syngas. As DME has no carbon-carbon bond in its molecular structure and is an oxygenate fuel, it's combustion essentially generates no soot. DME has such cetane number of 55~60 that it can be used as a diesel engine fuel. However, DME has low lubricity but a proven method to solve the poor lubricity is by adding lubricity improver. Therefore, the aim of this study is to develop lubricity improver of DME as a transport fuel in Korea. In this study, we investigated a possibility of fatty acid ester compounds as a candidate to improve DME lubricity as compared with current lubricity improver of diesel. We also evaluated quality characteristics, storage stability of DME with lubricity additives.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.664-670
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• 1996

The aim of the present research program was to develop a strain of actinomycetes producing antifungal substance. Soil samples were collected from various sites in Korea and a number of actinomycetes were isolated from the soil samples by applying selective agar for actinomycetes. Among over 440 isolates, a strain (NA-4803) producing antifungal substance against Trichophyton spp. Nannizzia otae and Pyricularia oryzae was selected. The strain NA-4803 was identified as strain similar to Streptoverticillium blastmyceticum with respect to morphological and physiological characteristics, lecithinase and lipolytic activity, degradation of organic compounds, resistance to antibiotics and utilization of carbon and nitrogen sources. But it showed some differences such as positive reaction of nitrate reduction, negative reaction of L-tyrosine degradation, resistance to cephaloridine, and utilization of I -rhamnose and inulin. The strain NA-4803 was named as Streptoverticillium sp. NA-4803.

• Journal of the Korean Applied Science and Technology
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• v.30 no.3
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• pp.431-443
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• 2013

Sulfur content of diesel fuel has been cut down to under 10 ppm ULSD (ultra low sulfur diesel) level by environmental regulation with the aim of reducing exhaust emissions. This review discusses the methods and principles of sulfur reduction in diesel and presents an overview of new approaches for ultra-deep desulfurization. The deep HDS (hydrodesulfurization) problems of diesel streams is exacerbated by the inhibiting effect of co-existing aromatics, nitrogen compounds and $H_2S$. The new approaches to deep desulfurization includes non-HDS type processing schemes such as adsorptive, extractive and oxidative desulfurization.

• Archives of Pharmacal Research
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• v.27 no.11
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• pp.1123-1126
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• 2004

The bioassay-guided fractionation of protective agents against sepsis-induced lethality from the root cortex of Paeonia suffruticosa ANDREWS (Ranunculaceae) led to the isolation of eight known compounds: paeonol (1), 2,5-dihydroxy-4-methoxyacetophenone (2), acetovanillone (3), paeonoside (4), paeoniflorin (5), oxypaeoniflorin (6), apiopaeonoside (7), and methyl 3-hydroxy-4-methoxybenzoate (8). Among them, 3 showed the highest survival rate (100% with a dose of 30 mg/kg versus 17% for the control experiment) and reduced alanine aminotransferase level to be a half of the control value on the sepsis model induced by lipopolysaccharide/D-galactosamine.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.25-25
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• 2010

The spectroscopy over a region from 3 to 17 ${\mu}m$ based on the tuneable diode lasers (TDLAS) is the most powerful technique for in situ studies of the diagnostics of small molecules. The increasing interest in small molecules especially containing carbon, oxygen, hydrogen, and fluorine containing ones can be fulfilled by TDLAS at 0.0001 cm-1 resolution, because most of these compounds are infrared active. TDLAS provides a means of determining the absolute concentrations of the ground states of stable and transient molecular species, which can be employed for the time dependent studies in sub micro second scale. Information about gas temperature and population densities can also be derived from TDLAS measurements. Collisional energy transfer between the small molecules can be studied with TDLAS. Also, a variety of free radicals and molecular ions have been detected by TDLAS. Since plasmas with molecular feed gases are used in many applications, there are new applications in industrial field. Recently, the development of quantum cascade lasers (QCLs) offers an attractive new option for TDLAS.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.675-678
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• 1999

Fibrinolytic protease activity was detected in the fruit body of Pleurotus sajor-caju using a fibrin plate method. Two fibrinolytic activities (FPI and Ⅱ) were found at the regions of 14.5 and 86.0 kDa by using gel-filtration column chromatography. FPⅡ was identified as an alkaline protease, whereas FPⅠ was a neutral protease. Both were inhibited by phenanthrolin and EDTA, suggesting that they are metalloprotease. Inactivated enzyme activities were restored by adding Co/sup 2+/ or Zn/sup 2+/. Iodoacetate inhibited FPⅠ, but not FPⅡ. Both enzymes cleaved B/sub β/ and γ chains of the human fibrinogen. FPⅡ showed a preference to hydrophobic and bulky residues of nitroanilidine compounds as substrates, whereas FPⅠ preferred positively charged residues.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.510-512
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• 2010

A series of thiobarbituric acid derivatives were constructed and evaluated for inhibitory activity on hepatitis C virus NS5B polymerase. In biochemical assays using purified viral polymerase and RNA template, the $IC_{50}$ value was improved to 0.41 ${\mu}M$ from the original compound's 1.7 ${\mu}M$ value. In HCV sub genomic replicon assay, the $EC_{50}$ value was improved to 3.7 ${\mu}M$ from the original compound's 12.3 ${\mu}M$ value. $CC_{50}$ was higher than 77 ${\mu}M$ for all compounds tested, suggesting that they are useful candidates for anti-HCV therapy.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.4
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• pp.399-408
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• 2018

A lipidomic study on extensive plasma lipids in bacterial peritonitis (cecal ligation and puncture, CLP)-induced sepsis in mice was done at 24 h post-CLP. The effects of administration of lysophosphatidylcholine (LPC) and lysophosphatidic acid (LPA), compounds known to have beneficial effects in CLP, on the sepsis-induced plasma lipid changes were also examined. Among the 147 plasma lipid species from 13 lipid subgroups (fatty acid [FA], LPA, LPC, lysophosphatidylethanolamine [LPE], phosphatidic acid [PA], phosphatidylcholine [PC], phosphatidylethanolamine [PE], phosphatidylinositol [PI], monoacylglyceride [MG], diacylglyceride [DG], triacylglyceride [TG], sphingomyelin [SM], and ceramide [Cer]) analyzed in this study, 40 and 70 species were increased, and decreased, respectively, in the CLP mice. Treatments with LPC and LPA affected 14 species from 7 subgroups, and 25 species from 9 subgroups, respectively. These results could contribute to finding the much needed reliable biomarkers of sepsis.

• Korean Journal of Pharmacognosy
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• v.32 no.3 s.126
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• pp.253-256
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• 2001

The present study was designed for the improvement of routine measurement of superoxide and hydroxyl radical scavenging activities utilized by a microplate reader. Superoxide radical scavenging activity by the ascorbic acid, which is a well-known superoxide scavenger, was determined in a dose-dependent manner. Hydroxyl radical scavenging activity by the thiourea, which is a well-known hydroxyl radical scavenger, was also well detected in a dose-dependent manner. Our results suggest that the use of microplate reader to assay the superoxide and hydroxyl radical scavenging activities improves the accuracy of data and enables the use of much smaller amounts of samples and/or reagents, with much simpler experimental procedure. Therefore, These methods appear to be suitable for screening of superoxide and hydroxyl radical scavenging activities in both the plant medicinal extracts and the isolated compounds.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.1-9
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• 2000

This experiment was accomplished to investigate antioxidative activity of Korean mistletoe by organic solvents partitioning of methanol extact of 3 Korean mistletoes, fractionationing on column chromatography, and evaluation the reduction of a free radical ${\alpha}$,${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl. Butanol partition of Loranthus yadoriki MeOH extract showed higher electron donating ability than ${\alpha}$-tocopherol. It was thought phenolic compounds including gallic acid account for antioxidative activity, on execution sub-fractionation, electron donating ability evaluation, and GC/MS analysis, but further studies on what are major actives must be investigated exactly.