• The Korean Journal of Malacology
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• v.26 no.2
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• pp.107-114
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• 2010

To evaluate the culture conditions in oyster-farming waters, chemical and biological measurements were made in seawater and oysters from six bays around Tongyeong in November and December 2003. Nutrient levels in the seawater were higher in the western area than in the eastern area, in contrast to particulate organic matter and dissolved oxygen levels. The mean total polycyclic aromatic hydrocarbon ({\sum}PAH) content of the oysters was 194.5-375.9 ng/g dry weight, with four-ring compounds constituting 34.1%-79.6% of PAH. Despite wide temporal variations, a "western > eastern" spatial distribution of PAH was apparent. These low concentrations of PAHs indicate that Tongyeong waters are pristine in terms of PAH contamination. Among the hemocytic biomarkers, only lysosomal activity was significantly reduced in Hansan-Goje Bay, but did not correlate closely with PAH content. This finding indicates that the impact of PAH on cultured oysters is negligible around Tongyeong waters.

• Elastomers and Composites
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• v.42 no.1
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• pp.1-8
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• 2007

The cleavage of fullerene oxides with several aromatic amines such as 4-nitroaniline, 3-nitroaniline, 4-isopropylaniline in the present of $FeCl_3$ occurred under ultrasonic irradiation in air at $25{\sim}43^{\circ}C$. The aminated fullerenes were confirmed by MALDI-TOF-MS and UV-vis spectra.

• Korean Journal of Microbiology
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• v.28 no.3
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• pp.243-248
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• 1990

Genetically engineered strains of Pseudomonas, which could degrade the various aromatic hydrocarbons, were acclimated to the synthetic wastewater with increasing substrate concentration. All of the tested strains except KUD101 showed 70-90% of the COD removal efficiencies. Acclimated strains, Pseudomonas putida KUD106, KUD107 and KUD108 were inoculated into the ordinary activated sludge and these sludges were used in the dyeing or alkylbenzene wastewater treatment system. In the case of the wastewater containing alkylbenzene compounds, COD removal efficiency was 12-14% higher than that of the ordinary activated sludge, while it was not effective for dyeing wastewater. On the other hand, the floc formation of the activated sludge inoculated with genetically engineered strains was more rapid in both wastewaters tested than that of the activated sludge by the ordinary natural strains.

• Journal of Environmental Health Sciences
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• v.10 no.2
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• pp.61-68
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• 1984

공기 중에는 benzo(a)pyrene을 위시한 여러 가지 polynuclear aromatic hydrocarbons(PNAs)가 존재하고 있으며, 그 측정방법이 매우 복잡하여 아직 통일된 적절한 방법이 없다. 본 연구는 공기 중의 PNAs를 측정하기 위한 적절한 방법을 개발하기 위하여 여러 가지 실험을 실시하였고 또 실제로 근로자들을 대상으로 공기를 채취하여 분석한 결과는 다음과 같다. (1) 공기 중 PNAs의 채취방법으로는 Teflon filter와 Polyurethane foam 또는 XAD-2를 연결하여 사용하는 것이 가장 좋은 효과를 보였다. (2) 검체에서 PNAs를 추출하는 방법으로는 methylene chloride를 이용한 초음속진동법 (ultra sonication)이 효과적이었다. benzene과 cyclohexane은 추출효과가 methylene chloride보다 적었으며, 초음속진동시간은 15분이 가장 적절하였다. (3) 분석법으로는 high pressure liquid chromatograph(HPLC)가 적절하였다.

• 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.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.1
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• pp.56-60
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• 2016

Benzyltrimethylammonium dichloroiodate in the presence of $ZnCl_2$ has been used for aromatic iodination of electron rich aromatic compounds. However, Baylis-Hillman type regioselective ${\alpha}$-iodination was carried out electronically rich coumarin compound under mild reaction condition with excellent chemical yield. Finally, $BBr_3$ demethylation gave ${\alpha}$-iododaphnetin.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.67-72
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• 1986

Aromatic hydrocarbon degrading bacteria were isolated from industrial waste by using an agar plate method. The isolate DY-1 was identified as Acinetobacter sp. and found to utilize phenanthrene as tis sole carbon source. THe bacteria were proved to produce salicylic acid as an intermediate from phenanthrene through naphthalene pathway, when the products in the culture were wxamined by thin-layer chromatography. THe $Phn^+$ genes were found to be involved in two plasmids of about 4 and 40kb which were lost and not detected in the DNA samples prepared from the mitomycin C-cured cells by a gel electrophoretic analysis.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.323-327
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• 2005

The effects of commercial marinades were evaluated for their influence on heterocyclic aromatic amine (HAA) formation and overall mutagenicity in fried beef steaks. Three different commercial marinades A, B, and C tested individually reduced the total HAA formation in fried beef steaks by 44, 38, and 40%, respectively. Three different commercial marinades were also effective in reducing the overall mutagenicity in fried beef steaks. There was, however, no significant difference in the inhibition achieved with three different commercial marinades. Reduction of overall mutagenicity was related to the decrease in HAA formation in fried beef steaks.

• Journal of the Korean Magnetic Resonance Society
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• v.22 no.4
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• pp.115-118
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• 2018

Dipyrromethane 2 functionalized with 3-chloropropyl group on the meso carbon undergoes an unusual intramolecular electrophilic aromatic substitution reaction in the presence of $NaN_3$ instead of a simple nucleophilic substitution reaction. As a result, a new chiral dipyrromethane 1 was synthesized. In this reaction, the ${\beta}$-carbon of the pyrrole ring functions as a nucleophile while the carbon next to the chlorine atom acts as an electrophile. Interestingly, this reaction progresses even in the absence of an acid catalyst. Compound 1 was fully characterized by $^1H-^1H$ and $^1H-^{13}C$ COSY NMR spectroscopic analyses and the high resolution EI mass spectrometry.

• Advances in environmental research
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• v.7 no.3
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• pp.177-200
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• 2018

Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) in the surface water from the coastal areas of Bangladesh were analyzed by GC-MS/MS. Samples were collected in winter and summer, 2015. The total concentration of PAHs (${\Sigma}PAHs$) showed a slight variation in the two seasons, which varied from 855.4 to 9653.7 ng/L in winter and 679.4 to 12639.3 ng/L in summer, respectively. The levels of ${\Sigma}PAHs$ were comparable to or relatively higher than other coastal areas around the world. The areas with recent urbanization and industrialization (Chittagong, Cox's Bazar and Sundarbans) were more contaminated with PAHs than the unindustrialized area (Meghna Estuary). Generally, 2-3-ring PAHs were the dominant compounds. Molecular ratios suggested that PAHs in the study areas could be originated from both pyrogenic and petrogenic sources. The risk assessment revealed the extremely high ecological risk of PAHs, indicating an intense attention should be paid to PAHs pollution in the coastal areas of Bangladesh.