• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.435-441
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• 2004

A drum bioreactor was used for the treatment of sandy soil contaminated with three kinds of aromatic compounds (phenol, naphthalene, and phenanthrene), and its performance was evaluated in two different operation modes; intermittent and continuous rotation of drum. When the drum bioreactor was operated with one rotation per day, the microbial growth was relatively low, and most of the compounds remaining in soil, except naphthalene of 90 mg/kg dry soil, disappeared mainly due to volatilization. In contrast, when the drum was continuously rotated at 9 rpm (rotation/min), the number of microorganisms was drastically increased and nitrate was consumed for growth as a nitrogen source. Phenol and phenanthrene were removed at rates of 56.7 mg/kg dry soil/day and 3.2 mg/kg dry soil/day, respectively.

• Bulletin of the Korean Chemical Society
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• v.21 no.8
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• pp.809-812
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• 2000

Treatment of the aromatic compounds with benzyl halides in the presence of a catalytic amount of indunm gave the corresponding diarylmethane products in good to excellent yields.

• Journal of Korean Society on Water Environment
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• v.18 no.4
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• pp.411-419
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• 2002

In this study, the series of ultrasonic irradiation for removal of refractory aromatic compounds has been selected as a model reaction in the batch reactor system in order to obtain the reaction kinetics. The products obtained from the ultrasonic irradiation were analysed by GC and GC/MSD. The decomposition of benzene produced toluene, phenol, and C1-C4 compounds, while the intermediates during the ultrasonic irradiation of 2,4-Dichlorophenol(DCP) were phenol, HCl, catechol, hydroquinone, and benzoquinone. It was found that more than 80% of benzene, and 2,4-DCP solutions were removed within 2 hours in all reaction conditions. The reaction order in the degradation of these three compounds was verified as pseudo-zero or first order. From the fore-mentioned results, it can be concluded that the refractory organic compounds could be removed by the ultrasonic irradiation with radicals, such as $H{\cdot}$ and $OH{\cdot}$ radical causing the high increase of pressure and temperature. Finally, it appeared that the technology using ultrasonic irradiation can be applied to the treatment of refractory compounds which are difficult to be decomposed by the conventional methods.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.490-497
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• 1999

The objectives of this study were to identify aroma characteristics of Tricholoma matsutake(S. Ito et Imai) Sing. growing in different geograghic ranges in South Korea. Mushrooms were collected from 11 major sites which included four sites(Bonghwa, Uljin, Goryung and Chungdo) in Kyongbuk Province, three sites(Changnyung, Hadong and Hamyang) in Kyongnam Province, two sites(Yangyang and Inje) in Kangwon Province, one site(Goisan) in Choongbuk Province, and one site(Namwon) in Chonbuk Province. One of three mushrooms from each site were used for measurements of aromatic characteristics. Aromatic compounds were identified using a dynamic headspace trap method at $40^{\circ}C$ and GC-MSD(gas chromatograph-mass spectrometric detector) method. A total of 25 aromatic compounds were identified. Large variations in the composition and amount of aromatic compounds were noticed. Major aroma compound was 1-octen-3-ol, while methyl cinnamate known as the major aroma compound in matsutake was not detected at all. The total amount of aromatic compounds was highest in Bonghwa, and decreased in the order of Chungdo, Inje, Hamyang, Uljin, and Yangyang. Based on the total amount, kinds and amounts of individual aromatic compounds, the mushrooms from 11 major sites were grouped into following four types : 1) Bongwha Type : the total amount of aromatic compounds was highest, with major compound being 3-methyl 1-butanol. 2) Hamyang Type including Chungdo, Yangyang and Inje : 1-octen-3-of comprised 2/3 of total aromatic compounds, with second major being 3-methyl butanal. 3) Uljin Type : 1-octen-3-ol comprised 94% of total aromatic compounds, with other compounds being almost nothing. 4) Goisan Type including Goryung, Namwon, Changnyung, and Hadong : the total amount of aromatic compounds was lower than other three types.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.748-751
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• 1997

The study was carried out to identify compositions and recovery yield of aromatic compounds of flower in Chinese yam (Dioscorea batatas Decne). Total 26 volatile aromatic compounds were identified and peak area percentage of aliphatic alcohol in Dan-ma was higher than in Jang-ma. Major volatile aromatic compounds analyzed by GC/MS were 1,2-butyleneglycol, phenylalcohol, caproic acid, cinnamic alcohol, and palmitic acid. Recovery yield of essential oils of Dan-ma was higher than in Jang-ma as 0.983％. As a result, it was concluded that Chinese yam was worthy of cultivating as perfume and medicinal crops.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.549-551
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• 2001

The heavy use of petroleum products in modern livings has brought ubiquitous environmental contaminants of aromatic compounds, which persist in aquatic and geo-environment without the substantial degradation. The persistence and accumulation of the aromatic compounds, which include xylene, phenol, toluene, phthalate, and so on are known to cause serious problems in our environments. Some of soil and aquatic microorganisms facilitate their growth by degrading aromatic compounds and utilizing degrading products as growth substrates, the biodegradation helps the reentry of carbons of aromatic compounds, preventing their accumulation in our environments. The metabolic studies on the degradation of aromatic compounds by microoganisms were extensively carried out along with their genetic studies. A Rhodococcus sp. EL-GT isolated in activated sludges has shown the excellent ability to grow on phenol as a sole carbon source. In the present study investigated a gene encoding phenol-degrading enzymes from a Rhodococcus sp. EL-GT.

• Journal of the Korean Society of Safety
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• v.36 no.1
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• pp.1-8
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• 2021

To simulate a process model in the field of chemical engineering, it is very important to identify the physical properties of novel materials as well as existing materials. However, it is difficult to measure the physical properties throughout a set of experiments due to the potential risk and cost. To address this, this study aims to develop a property prediction model based on the group contribution method for aromatic chemical compounds including benzene rings. The benzene rings of aromatic materials have a significant impact on their physical properties. To establish the prediction model, 42 important functional groups that determine the physical properties are considered, and the total numbers of functional groups on 147 aromatic chemical compounds are counted to prepare a dataset. Support vector regression is employed to prepare a prediction model to handle sparse and high-dimensional data. To verify the efficacy of this study, the results of this study are compared with those of previous studies. Despite the different datasets in the previous studies, the comparison indicated the enhanced performance in this study. Moreover, there are few reports on predicting the physical properties of aromatic compounds. This study can provide an effective method to estimate the physical properties of unknown chemical compounds and contribute toward reducing the experimental efforts for measuring physical properties.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1481-1483
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• 1998

we have investigated the effect of aromatic compounds and tree inception and growth in low density polyethylene, for AC voltage and Impulse voltage. 2kinds of aromatic compounds are selected. Each additive (m-cresol, aniline) was mixed in low density polyethylene. For AC voltage, 10wt% $\sim$ 15wt% m-cresol can be shown to be the effective inhibitor to tree initiation. But, For Impulse voltage, 10wt% $\sim$ 15wt% aniline is effective inhibitor to tree initiation.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1477-1484
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• 2007

Artificial neural networks (ANNs), for a first time, were successfully developed for the prediction partial molar heat capacity of aqueous solutions at infinite dilution for various polar aromatic compounds over wide range of temperatures (303.55-623.20 K) and pressures (0.1-30.2 MPa). Two three-layered feed forward ANNs with back-propagation of error were generated using three (the heat capacity in T = 303.55 K and P = 0.1 MPa, temperature and pressure) and six parameters (four theoretical descriptors, temperature and pressure) as inputs and its output is partial molar heat capacity at infinite dilution. It was found that properly selected and trained neural networks could fairly represent dependence of the heat capacity on the molecular descriptors, temperature and pressure. Mean percentage deviations (MPD) for prediction set by the models are 4.755 and 4.642, respectively.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.59-64
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• 2011

Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits(UELs), the upper flash point of n-alkanes and aromatic compounds were measured under the VLE(vapor-liquid equilibrium) state by using Setaflash closed cup tester(ASTM D3278). The UELs calculated by Antoine equation and chemical stoichiometric coefficient tusing the experimental upper flash point were compared with the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.