• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.113-118
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• 2003

An investigation has been carried out on collision-induced dissociation (CID) in the development of an analytical protocol for the determination of polycyclic aromatic hydrocarbons (PARs) by ion trap tandem mass spectrometry. Two different considerations were used to choose the optimal CID conditions for complex matrix environmental samples, namely, to determine the highest signal-to-noise (SIN) ratio and the other to eliminate the background interferences originated from complex matrix samples. The PAR content of agricultural soil was measured to estimate overall distribution of PAR in throughout the country, we collected and analyzed 226 soil samples from paddy and upland soil. The average content of total PAR in all samples was 236 ${\mu}g$ $kg^{-1}$, and the range was from 23.3 to 2, 834 ${\mu}g$ $kg^{-1}$. The overall distribution of PAR was found to be closely related to the pollution sources, the size of city and the type of industry.

• Macromolecular Research
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• v.14 no.3
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• pp.306-311
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• 2006

New unsymmetrical ($\alpha$-Diimine)nickel(II) catalysts having different pendent groups at the ortho positions on aromatic rings were synthesized and subjected to propylene polymerizations with MAO (methylaluminoxane). Structural analyses of the resulting polypropylenes by $^1H\;and\;^{13}C\;NMR$ showed that the ortho substituents on aromatic rings of ($\alpha$-diimine)nickel(II) catalyst affected significantly the polypropylene microstructure. While $C_s$ symmetric catalyst afforded a syndiotactic polypropylene (rr triad content=66%) due to the syndiospecific chain end control, $C_1$ symmetric catalysts produced much less stereoregular polypropylenes (rr triads content <50%), presumably because of collision of the isospecific site control with the syndiospecific chain end control.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.672-677
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• 1996

Volatile flavour components rates from aromatic rices were analyzed by Electronic nose systems. In functional group, polar compounds and aldehyde compounds showed much of volatile flavour components than apolar compounds, sulphur compounds and aminated compounds. The profiles of volatile flavour components rates were markedly differents of sen-sing times, amylose content.

• International Journal of Advanced Culture Technology
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• v.4 no.4
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• pp.64-69
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• 2016

Currently on the school education site, various multimedia contents are used to effectively deliver knowledge to the students and increase interest in class. The majority of the multimedia contents currently used in classes are composed of visual and auditory information. This paper intends to maximize actuality and immersion in the content by adding olfactory information to the existing visual and auditory data. Tangible contents were developed based on the details of aromatic plants learned in the fifth grade of elementary school. The shape and explanation of the aromatic plants are displayed with visual and auditory information, and an aroma spraying application is used to allow the students to smell the aromatic plants. After conducting the class using the developed contents, the students' satisfaction of the class, as well as their overall academic understanding, were investigated. Upon doing so, it was discovered that the students' academic understanding and satisfaction increased in comparison to classes comprised of only visual and auditory contents.

• Journal of Environmental Science International
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• v.2 no.1
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• pp.57-68
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• 1993

Polycyclic aromatic hydrocarbons (PAMs) are ubiquitous contaminants in marine environments. PAHs enter estuarine and nearshore marine environment via several routes such as combustion of fossil fuels, domestic and industrial effluents and oil spills PAHs have been the focus of numerous studies in the world because they owe potentially carcinogenic, mutagenic, and teratogenic to aquatic organisms and humans from consuming contaminated food. However, one can hardly find any available data on PAM content in marine organisms in Korea. The present study was carried out in order to determine PAH content in oysters from the intertidal and subtidal zones of Chinhae Bay, which is located in near urban communities and an industrial complex, and the bay is considered to be a major repositories of PAHs. 16 PAHs were analyzed by High Performance Liquid Chromatography (HPLC) with uv/vis and fluorescence detectors in oysters: they are naphthalene (NPTHL), acenaphthylene (ANCPL), acenaphthene (ACNPN), fluorene (FLURN), phenanthrene (PKEN), anthracene (ANTHR), fluoranthene (FLRTH), pyrene (PYRf), benzo(a)anthracene (BaA), chrysene (CHRY), benzo(b)- fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), dibenz(a, h)anthracene (DhA), benzo(g, h, i)peryne (Bghip) and indeno(1, 2, 3, -cd)pyrene (I123cdP). The PAH contents in oysters from the intertidal and subtidal zones of Chinhae Bay ranged from < 0.1 to 992.0 $\mu\textrm{g}$/kg (mean 69.8 $\pm$ 9.8 $\mu\textrm{g}$/kg). Key words . polycyclic aromatic hydrocarbon, high performance liquid chromatography, oyster, Chinhae Bay.

• Journal of Ginseng Research
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• v.42 no.2
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• pp.158-164
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• 2018

Background: The study was carried out to assess the genetic variability present in ashwagandha and to examine the nature of associations of various traits to the root yield of the plant. Methods: Fifty-three diverse genetic stocks of ashwagandha (Withania somnifera) were evaluated for 14 quantitative characteristics. Analysis of variance, correlation, and path coefficient analysis were performed using the mean data of 2 years. Results: Analysis of variance revealed that the genotypes differed significantly for all characteristics studied. High heritability in conjunction with high genetic advance was observed for fresh root weight, 12 deoxywithastramonolide in roots, and plant height, which indicated that selection could be effective for these traits. Dry root weight has a tight linkage with plant height and fresh root weight. Further, in path coefficient analysis, fresh root weight, total alkaloid (%) in leaves, and 12 deoxywithastramonolide (%) in roots had the highest positive direct effect on dry root weight. Conclusion: Therefore, these characteristics can be exploited to improve dry root weight in ashwagandha genotypes and there is also scope for the selection of promising and specific chemotypes (based on the alkaloid content) from the present germplasm.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.2
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• pp.333-339
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• 2008

Korean ginseng (Panax ginseng C. A. Meyer) has been used as an important medicinal plant in the Orient for a long time. It has been claimed that ginseng has many beneficial bioactive effects on human health, such as antitumor, antistress, antiaging and enhancing immune functions. Red ginseng possibly have new ingredients converted during steaming and dry process from fresh ginseng. Kujeungkupo method which means 9 repetitive steaming and drying process was used for the processes of green tea, Polygonatum odoratum, and Rehmanniae radix preparata. In this study, ingredient conversion of ginseng by 9 repetitive steaming and drying process were investigated measuring conversion efficiency of brown materials, crude lipids, crude proteins and aromatic compounds. Brown materials, as an antioxidant, in red ginseng were produced through non-enzymatic reaction by heat. Repetitive steaming and drying treatments on ginseng root contiunously increased the content of brown materials and the chromaticity. Crude lipids were degraded by heat and converted into volatile aromatic ingredients. Crude lipids were degraded and decreased by 0.52% after the 5th and 7th. Crude proteins were also decomposed and converted to amino acid. Crude proteins after the 9th treatment were decreased by more than 85% as increased times of treatments. A bicyclogermacrene as aromatic material was decreased as increased treatment times, while but a aromatic caramel was increased.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.12
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• pp.1121-1126
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• 2010

This study is to investigate the effects of aromatics and T90 for low cetane number (CN) fuels on combustion and exhaust emissions in low-temperature diesel combustion. We use a 1.9-L common rail direct injection diesel engine at 1500 rpm and 2.6 bar BMEP. Low temperature diesel combustion was achieved via a high external EGR rate and strategic injection control. The tested fuels four sets: the aromatic content was 20% (A20) or 45% (A45) and the T90 temperature was $270^{\circ}C$ (T270) or $340^{\circ}C$ (T340) with CN 30. Given the engine operating conditions, the T90 was the stronger factor on the ignition delay time, resulting in a longer ignition delay time for higher T90 fuels. All the fuels produced nearly zero PM because of the extension of the ignition delay time induced by the low cetane number. The aromatic content was the main factor that affected the NOx and the NOx increased with the aromatic content.

• Food Science and Preservation
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• v.30 no.6
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• pp.1029-1042
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• 2023

This study aimed to apply the technology of increasing the volatile aromatic compounds in wine through mixed fermentation of Saccharomyces cerevisiae and non-Saccharomyces yeasts to make distilled soju. The expectation was to induce changes in metabolites such as volatile aromatic compounds before the distillation process, followed by concentrating these compounds through distillation to enhance the odor property of distilled soju. Additionally, the study aimed to examine the impact of mixed fermentation with S. cerevisiae and non-Saccharomyces yeasts on distilled soju's free amino acid content. As a result, when Hanseniaspora uvarum yeast was used, there was an increase in the content of low molecular weight volatile aroma compounds, particularly esters. Distilled soju co-fermented with S. cerevisiae and H. uvarum SJ69 exhibited similar amino acid content to distilled soju single-fermented with S. cerevisiae. However, distilled soju co-fermented with S. cerevisiae and H. uvarum S6, a decrease in amino acid content. Sensory evaluation results indicated a higher odor score in distilled soju co-fermented with S. cerevisiae and H. uvarum S6, suggesting that the mixed fermentation technology utilizing H. uvarum could contribute to improving the quality of distilled soju in the future.

• Journal of Environmental Science International
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• v.11 no.5
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• pp.455-461
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• 2002

Polycyclic aromatic hydrocarbons(PAHs) are ubiquitous contaminants in coastal marine environment. PAHs enter estuarine and nearshore marine environment via several routes such as combustion of fossil fuels, domestic and industrial effluents and oil spills. In August of 1997, mussels(Mytilus edulis) were collected at 6 sites near Kori nuclear power plant in order to analyze the PAH content by HPLC with uv/vis detection. Unfortunately, I could not find any living oysters in which I firstly intended to measure the PAH content in the study area. NPTHL and ANCPL were the major dominant PAH compounds in mussels living in the intertidal zone of Kori, Korea, and DahA, BbF, BaP were the next dominant PAH group in mussels in the study area. The mean concentrations of 15 PAH in mussels ranged from 3.2 to 1,680 ppb(mean 105$\pm$60.5 ppb). Compared with other studies world over, the concentrations of carcinogenic PAHs were relatively low in mussels in the study area, even though total PAH content was rather high. According to N/P(Naphthalene/Phenanthrene) ratio(147) and the ratio of 2∼3 ring to 3∼5 ring PAHs(58∼90 %) in mussels in the study area, I expect that the major source of PAHs in this study area is rather fresh petroleum-derived. This study presents preliminary data for the PAH levels in mussels from the intertidal zone of Kori, and the data will hopefully be utilized for the assessment of oil pollution in the East Sea, Korea.