• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.277-278
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• 2003

Cyclone separators are widely used for cleaning gas streams or for catalyst recovery. For many years, the complexity of the gas flow pattern in cyclones has been a matter of many experimental and theoretical work. At present, precise flow measurements have been performed by means of LDA and hot-wire anemometry (Patterson and Munz, 1996; Hoekstra et al., 1999; Peng et al., 2002). In the theoretical work, Computational fluid dynamics (CFD) codes are frequently employed for simulating cyclone gas-particle flows(Hoekstra et al., 1999). (omitted)

• Journal of Environmental Science International
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• v.16 no.2
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• pp.151-158
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• 2007

In order to investigate the compositions and the emission rates of monoterpenes emitted from coniferous trees, those from Larix leptoleis (Sieb, et Zucc.) Gordon were measured. In spring and summer, the major monoterpenes were ${\alpha}-terpinene,\;{\alpha}-pinene$, myrcene; however, ${\alpha}-pinene\;and\;{\alpha}-terpinene$ were most abundant in fall. The total mean monoterpene emission rates were $0.455\;({\mu}gC/gdw/hr)$ during the whole period. The higher monoterpene emission rates were found in fall compared to those in spring and summer. In addition, the slopes (${\beta}\;value$) between emission rate and temperature were two times lower in fall than those in spring and summer. It was also found that Larix leptoleis (Sieb. et Zucc.) Cordon had lower monoterpene emission rates than P. densiflora and P. rigida.

• Journal of the Korean Wood Science and Technology
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• v.40 no.2
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• pp.141-146
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• 2012

The outer bark of Prunus sargentii was collected, air-dried and extracted with 70% aqueous acetone. Then it was successively partitioned with n-hexane, dichloromethane ($CH_2Cl_2$), ethyl acetate (EtOAc) and $H_2O$. From the EtOAc soluble fraction, four compounds were isolated by the repeated Sephadex LH-20 column chromatography. The isolated compounds were determined as (+)-catechin (1), (-)-epicatechin (2), taxifolin (3), and neosakuranin (4) by the spectroscopic analysis including $^1H$, $^{13}C$-NMR, and 2D-NMR spectrometers. The antioxidative activities on the isolated compounds and the separated fractions were evaluated by DPPH radical scavenging assay. The crude, EtOAc, and $H_2O$ soluble fractions indicated good antioxidative potential compared to the $CH_2Cl_2$ and n-hexane soluble fractions.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.165-166
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• 2001

HO$_2$ radical plays pivotal roles in the tropospheric $O_3$ formation chemistry. This radical oxidizes NO to NO$_2$ and thus HO$_2$ radical can lead to in-situ ozone formation. Numerous methods have been tried to measure concentrations of atmospheric HO$_2$ in gas phase. Detecting methods applied in the air are a chemical amplifier (Cantrell et al., 1996), FAGE (Fluorescence Assay with Gas Expansion) (Hard et al., 1984), and LIF (Laser-induced Fluorescence) (Stevens et al., 1994). These methods have been limited because of low sensitivity and interferences such as $O_3$, NO, and itself (Stevens et al.,1994). (omitted)

• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.480-485
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• 2009

Juglans mandshurica bark was collected and extracted with 70% aqueous acetone. The extracts were concentrated and then sequentially fractionated using n-hexane, $CH_2Cl_2$, EtOAc, and $H_2O$ to be freeze dried. A portion of $H_2O$ fraction was chromatographed on a Sephadex LH-20 column using aqueous methanol to isolate (S)-2,3-HHDP-D-glucopyranoside (1). Some of EtOAc fraction was also treated on a Sephadex LH-20 column using aqueous methanol and EtOH-hexane mixture to purify pedunculagin (2). The structures of these two epimeric ellagitannins were elucidated by spectroscopic tools, NMR and MS.

• Journal of the Korean Wood Science and Technology
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• v.47 no.1
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• pp.1-7
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• 2019

Japanese anise (Illicium anisatum L.) leaves were collected and ground after drying, then immersed with 50 % aqueous acetone for 3 days. After filtration, the extracts were fractionated with n-hexane, chloroform ($CHCl_3$), ethylacetate (EtOAc) and $H_2O$, and then freeze dried after concentration. A portion of EtOAc (3.12 g) and $H_2O$ (6.08 g) soluble fractions were chromatographed on a Sephadex LH-20 column with various aqueous MeOH solution to isolate the compounds. Compound 1 ((+)-catechin) was isolated from EtOAc soluble fraction. Compounds 2 (quercetin), 3 (quercitrin) and 4 (2''-O-rhamnosylvitexin) were isolated from $H_2O$ soluble fraction. For the first time, quercitrin (3) and 2''-O-rhamnosylvitexin (4) of the isolated compounds were obtained from the extracts of japanese anise leaves.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.216-217
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• 2002

Vitellogenin (VTG) is a Precursor form of egg yolk Proteins, which appear only in the blood circulation of female fish and its synthesis in the liver is considered to be regulated by several hormones. It has been reported that in addition to estradiol-17 $\beta$ (E2) several hormones are also involved in the production site of VTG, the liver (Peyon et al., 1996; Mori et al., 1998). (omitted)

• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.474-479
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• 2009

Pinus koraiensis inner bark was collected and extracted with 95% ethanol. The extracts were concentrated and then sequentially fractionated using n-hexane, $CH_2Cl_2$, EtOAc, and $H_2O$ to be freeze dried. A portion of EtOAc fraction (6.6 g) was chromatographed on a Sephadex LH-20 column using aqueous methanol to isolate (+)-catechin (1), (-)-epicatechin (2), and trans-pinostilbenoside (3). Resveratrol (4) and trans-pinostilbene (5) were isolated by column chromatography using EtOH-hexane mixture after purification with aqueous methanol. The structures of these stilbenosides and flavans were characterized by spectroscopic tools using NMR and MS.

• Journal of Forest and Environmental Science
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• v.23 no.1
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• pp.1-4
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• 2007

The bark of Juglans mandshurica Maxim. was collected, extracted with acetone-$H_2O$ (7:3, v/v), fractioned with n-hexane, $CH_2Cl_2$ and EtOAc, then each fraction was freeze-dried to give some powders. A portion of the EtOAc (28.4 g) fraction was chromatographed on a Sephadex LH-20 column eluting with a series of MeOH-$H_2O$ and EtOH-hexane mixture. Four gallotannins, gallic acid (1), ellagic acid (2), 1,2,4,6-tetra-O-galloyl-${\beta}$-D-glucose (3) and 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose (4), have been isolated from the EtOAc fraction Their structures were elucidated on the basis of chemical evidence and spectrometric analysis such as NMR and MS. The antioxidant activities on each fraction and the isolated gallotannins were evaluated by DPPH radical scavenging test.

• Korean Journal of Environmental Biology
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• v.24 no.2 s.62
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• pp.112-118
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• 2006

We report mitochondrial cytochrome b (cyt b) genes from greenling Hexagrammos otakii (Jordan et Starks) and spotty belly greenling, H. agrammus (Temminck et Schlegel) within Hexagrammidae, two species of aquaculture importance. Of 489 bp of the cytochrome b gene, a little variation occurred between species (96% similarity). The pairwise distance (0.0342) between greenling and spotty belly greenling in term of the Neighbor-joining method indicated that two species was close in molecular phylogenetic consideration. These findings are applicable to aquaculture, fisheries genetics and molecular phylogenetics in the genus Hexagrammos.