• Environmental and Resource Economics Review
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• v.29 no.2
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• pp.145-170
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• 2020

This study analyzes the dependence structure between energy (crude oil, natural gas, coal) prices and economic (real and financial) uncertainty. Summary of the results of the dependence structure between energy prices and economic uncertainty analysis is as follows. First, the results of model selection show that the BB7 copula model for the pair of crude oil price and economic uncertainty, the Joe copula model for the pair of natural gas price and economic uncertainty, and the Clayton copula model for the pair of coal price and economic uncertainty were chosen. Second, looking at the dependency structure, it showed that the pair of energy (crude oil, natural gas, coal) prices and real market uncertainty show positive dependence. Whereas, the only pair of financial market uncertainty-crude oil price shows positive dependency. In particular, crude oil price was found to have the greatest dependence on economic uncertainty. Third, looking at the results of tail dependency, the pair of real market uncertainty-crude oil price and pair of real market uncertainty-natural gas price have an asymmetric relationship with the upper tail dependency. It can be seen that the only pair of financial market uncertainty-crude oil represents asymmetric relationships with the upper tail dependencies. In other words, combinations with asymmetric relationships have shown strong dependence when negative extreme events occur. On the other hand, tail dependence between economic uncertainty and coal price be not found.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.170-175
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• 2004

In this paper we studied about Bacillus sp. TBM40-3 producing biosurfactants. The strains were isolated from Taeback Mountain soil and identified as Bacillus sp. by l6S rDNA nucleotides sequence analysis. The TBM40-3 was gram-positive and rod-shaped as observed by field emission scanning microscopy. After the cultivation TBM40-3 in LB broth for 90 h and the surface tension of supernatant was decreased to 29 mN/m. Emulsification activity and stability of crude biosurfactant was measured by using water-immiscible hydrocarbons and oil as substrate. Maximum emulsification activity and stability was obtained from soybean oil. Also, we confirmed that the TBM40-3 producing biosurfactant had an effect on crude oil while showing a superior effect as compared to chemically synthesized surfactants (SDS, Span85, Tween40, Triton X-100). As a result, the Bacillus sp. TBM40-3 producing biosurfactant had potent properties as an emulsifying agent and an emulsion stabilizing agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.747-752
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• 2011

We conducted a study to select a suitable natural antioxidant from tocopherol, rosemary extract, and green tea extract to be added to commercially-available palm oil to extend the shelf life of non-dairy cream. The green tea extract (400 ppm added) was the most effective of the 3 antioxidants added to the palm oil, increasing OSI time by a factor of 2.3. By examining the correlation coefficients among parameters for storage period, the sensory score indicated that the non-dairy cream was suitable. The shelf life of the TE (green tea extract, 400 ppm) and TEA (TE plus 0.002% ascorbic acid) oils was extended to 24% and 51% more than that of the control at $25^{\circ}C$, respectively. At $20^{\circ}C$, the shelf life of the TE oil was 2.5 months and that of the TEA oil was 5.5 months, increases of 28% and 62.5%, respectively, over the control.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.160-164
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• 2009

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.157.2-158
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• 2002

• Ocean and Polar Research
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• v.36 no.2
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• pp.145-156
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• 2014

Macrobenthic biodiversity in the rocky intertidal areas of the Tae-an region, Republic of Korea, has decreased since the Hebei Spirit oil spill in December 2007. We aimed to investigate ecological roles of Pacific oyster (Crassostrea gigas) because recruitment and growth of oysters are critical to the recovery of damaged rocky shore ecosystem. We surveyed two sites monthly: natural rocky substrate and farming substrate, from July 2012 to January 2013 to identify and compare the changes in macrobenthic fauna. The abundance of young oysters was higher at the natural site. On the other hand, the mean height of oyster on the farming substrate was more than twice as great. The abundance of oyster at the natural site increased until October and then continuously decreased until end of study period. However, the abundance of oyster at the farming site constantly decreased from the beginning of study period. These different growth patterns might be attributable to spatial competition between oyster and a barnacle species (Balanus albicostatus) and environmental factors. At the natural site, physical stress factors including dramatic temperature changes and desiccation a few of the major factors limiting growth during aerial exposure. In addition, motile macrobenthos could be detrimental to oysters because they interrupt filter-feeding activities and hence hamper the growth of oysters. We show the higher recruitment of oysters at the natural site and healthy growth in the farming substrate are due to complicated differences in physical and biological stress factors.

• Korean Journal of Pharmacognosy
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• v.21 no.2
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• pp.121-125
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• 1990

Essential oil of the root of Angelica dahurica Benth et Hook(Umbelliferae) was investigated. Essential oil was obtained from the dried roots by steam distillation and fractionated by column chromatography. Each isolate or fraction was identified by GC, GC-MS and spectral analysis. It was found to contain eleven monoterpenes such as ${\alpha}-pinene(4.74%),\;campben, {\beta}-pinene,\;myrcene,\;{\alpha}-phellandrene,\;{\delta}-3-carene(39.4%),\;{\alpha}-terpinene,\;{\rho}-cymene,\;{\beta}-phellandrene,\;{\alpha}-terpinene,\;terpinolene\;and\;also\;found\;to\;contain\;4-vinylguaiacol,\;iso-elemicin,\;{\beta}-elemene$, caryophyllene, ligustilide, osthol and seven tentatively identified sesquiterpenes.

• Korean Journal of Pharmacognosy
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• v.19 no.4
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• pp.239-247
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• 1988

Essential oil of the root of Angelica gigas Nakai (Umbelliferae) was investigated. Essential oil was obtained from the dried roots by steam distillation and fractionated by column chromatography. Each isolate or fraction was identified by GC, GC-MS and spectral analysis. It was found to contain eleven monoterpenes such as ${\alpha}-pinene,\;camphene,\;{\beta}-pinene,\;myrcene,\;{\alpha}-phellandrene,\;{\Delta}-3-carene,\;{\alpha}-terpinene,\;p-symene,\;limonene,\;{\gamma}-terpinene$ and terpinolene and also found to contain 4-vinylguauacol, myristicin, elemol, ${\beta}-eudesmol,\;{\alpha}-eudesmol,\;four\;sesquiterpenes\;involving\;{\Delta}-elemene$. Four sesquiterpenes and five sesquiterpene alcohols were tentatively identified by comparison of their mass spectra.

• Korean Journal of Pharmacognosy
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• v.23 no.1
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• pp.29-33
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• 1992

The essential oils of Lycopus lucidus have been studied. The essential oil obtained from the dried herba by steam distillation followed by fractionation by column chromatography was analysed by gas chromatography-mass spectrometry(GC-MS). The compounds identified by GC-MS were carvacrol, 2,5-dimethoxy-p-cymene, trans-caryophyllene, spathurenol and $trans-{\beta}-farnesene$. Two compounds, thymol and caryophyllene were isolated by silica gel column chromatography and analyzed by TLC, IR, Mass and NMR. And the weak diuretic effects of essential oil and water extract from the dried drugs were observed in rats.

• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.125-129
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• 1999

The influence of dietary cholesterol on phospolipid metabolism in rat liver microsmes was studied in rats fed a diet containing fish oil(FO) or beef tallow (BT). The hepatic phospholipid content decreased wherease gepatic triglyceride and cholesterol increased significantly in both groups after cholestered supplementation. Plasma concentrations of phospholipid and traiglyceride increased with cholesterol supplement in both groups while cholesterol decreased only moderately in the FO group. Dietary cholesterol affected microsomal phosphiolpids in liver ; the proportation of phosphatidylcholine decreased in the FO group, an d it also slightly decreased in the BT group at the expense of phosphatidylethanolamine. The activity of CTP : phospocholine cytidylytransferase , the rate-limiting enzyme of phosphatidylcholine synthesis, increased inhepatic mocrosomes whreas it decreased in hepatic cytosol of both groups by cholesterol supplementation. In conclusion, these indicated that the dietary cholesterol profoundly influences phospholipid metabolism in the rat liver.