• Journal of Korean Society for Atmospheric Environment
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• v.17 no.3
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• pp.233-240
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• 2001

The composition of volatile organic compounds (VOCs) was anlyzed for major emission sources such as vehicle exhaust, gasoline and diesel vapor, organic solvent vapor, and butane fuel gas. Low carbon-numbered hydrocarbons were found to be the dominant components of gasoline vehicle exhaust. In gasoline evaporative vapor, the predominant constituents were found to be butane and iso-pentane regardless of ambient air temperature. In case of diesel evaporative vapor was similar to those of gasoline evaporative vapor. The composition of organic solvent vapor from painting, ink and petroleum consisted mostly or aromatic compounds such as toluene and m, p, o-xylene. The hydrocarbon fraction of butane fuel gas. which is used by portable bunner, consisted mainly of propane (34%) and butane(70%).

• Asian Journal of Atmospheric Environment
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• v.2 no.1
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• pp.34-46
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• 2008

Emissions inputs for use in air quality modeling of Korea were generated with the emissions inventory data from the National Institute of Environmental Research (NIER), maintained under the Clean Air Policy Support System (CAPSS) database. Source Classification Codes (SCC) in the Korea emissions inventory were adapted to use with the U.S. EPA's Sparse Matrix Operator Kernel Emissions (SMOKE) by finding the best-matching SMOKE default SCCs for the chemical speciation and temporal allocation. A set of 19 surrogate spatial allocation factors for South Korea were developed utilizing the Multi-scale Integrated Modeling System (MIMS) Spatial Allocator and Korean GIS databases. The mobile and area source emissions data, after temporal allocation, show typical sinusoidal diurnal variations with high peaks during daytime, while point source emissions show weak diurnal variations. The model-ready emissions are speciated for the carbon bond version 4 (CB-4) chemical mechanism. Volatile organic carbon (VOC) emissions from painting related industries in area source category significantly contribute to TOL (Toluene) and XYL (Xylene) emissions. ETH (Ethylene) emissions are largely contributed from point industrial incineration facilities and various mobile sources. On the other hand, a large portion of OLE (Olefin) emissions are speciated from mobile sources in addition to those contributed by the polypropylene industry in point source. It was found that FORM (Formaldehyde) is mostly emitted from petroleum industry and heavy duty diesel vehicles. Chemical speciation of PM2.5 emissions shows that PEC (primary fine elemental carbon) and POA (primary fine organic aerosol) are the most abundant species from diesel and gasoline vehicles. To reduce uncertainties in processing the Korea emission inventory due to the mapping of Korean SCCs to those of U.S., it would be practical to develop and use domestic source profiles for the top 10 SCCs for area and point sources and top 5 SCCs for on-road mobile sources when VOC emissions from the sources are more than 90% of the total.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.553-556
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• 2000

Possibility of biological nitrogen treatment was tested in wastewaters with low C/N ratio. Chlorella kessleri was inoculated at $10^6\;cell/mL$ of initial density in two different artificial wastewaters: one that contained glucose for organic carbon source and the other without carbon source. Nitrate could be successfully reduced below 10 mg $NO_3/mL$ from initial nitrate concentration of 560 mg $NO_3/mL$ in 10 days even in the wastewater without carbon source, This 98% removal of nitrate without extra organic carbon source lights up the future of biological wastewater treatment, where the insufficient ability of nitrogen removal is a major problem.

• Journal of Industrial Technology
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• v.16
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• pp.13-24
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• 1996

This research aims to investigate the effects of an internal carbon source in the denitrification of piggery wastewater. In this study, the raw wastewater and the effluent from each of anoxic basin and anaerobic basin were used as the internal carbon sources. The experiments were carried out in batch system and the results are as follows ; i) Denitrification rates were the highest in the raw wastewater and the lowest in the anaerobic effluent. ii) The piggery wastewater contained about 60 percent of the readily biodegradable organic(RDCOD), which led to a conclusion that the raw wastewater could be used as the internal carbon source for the denitrification. For the efficient denitrification, pre-denitrification process was found profitable. iii) In denitrification, alkalinity production rates were in the range of 3.4 to $3.6mgCaCO_3/mgNO_3-N$. iv) The denitritation of piggery wastewater came out to be possible, and the rate of organic carbon consumption decreased about 10 percent.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.736-743
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• 2015

Organic matter plays important roles in soil ecosystem in terms of carbon and nitrogen cycles. Due to recent concerns on climate change, carbon sequestration in agricultural land has become one of the most interesting and debating issues. It is necessary to understand behavior of soil carbon for evaluating decomposition or sequestration of organic matter and analyzing potential carbon decomposition pattern about the kinds of organic matter sources to cope with well. In order to evaluate decomposition of soil carbon according to organic material during cultivating rice in paddy field, we treated organic material such as hairy vetch, rice straw, oil cake fertilizer, and manure compost at $50{\times}50{\times}20cm$ blocks made of wood board, and analyzed carbon contents of fulvic acid and humic acid fraction, and total carbon periodically in 2013 and 2014. Soil sampling was conducted on monthly basis. Four Kinds of organic matter were mixed with soil in treatment plots on 2 weeks before transplanting of rice. The treatment of animal compost showed the highest changes of total carbon, which showed $7.9gkg^{-1}$ in May 2013 to $11.6gkg^{-1}$ in October 2014. Fulvic acid fraction which is considered to easily decompose ranged from 1 to $2gkg^{-1}$. Humic acid fraction was changed between 1 to $3gkg^{-1}$ in all treatments until organic material had been applied in 2014. From May to August in the second year, the contents of humic acid fraction increased to about $4gkg^{-1}$. The average of humic fraction carbon at treatments of animal compost was recorded highest among treatments during two years, $2.1gkg^{-1}$. The treatment of animal compost has showed the lowest ratio of fulvic acid fraction, humic acid fraction compared with other treatments. The average ratio of fulvic fraction carbon in soil ranged from 16 to 20%, and humic fraction carbon ranged from 19 to 22%. In conclusion, animal compost including wood as bulking agent is superior in sequestrating carbon at agricultural land to other kinds of raw plant residue.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.4
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• pp.363-376
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• 2003

In this study, the fugitive emission characteristics of airborne volatile organic compounds from different source categories were evaluated with respect to the concentrations measured in the vicinity of the sources. A total of 22 different sources were investigated, including gasoline storage and filling stations, painting spray booth, laundry, printing officer, textile industries, and a number of environmental sanitary facilities such as landfill, wastewater treatment and incineration plants. The target VOCs included 83 individual compounds, which were determined by adsorption sampling and thermal desorption coupled with GC/MS analysis. Overall, the aliphatic compounds appeared to be the most abundant class of compounds in terms of their concentrations, followed by aromatic, and halogenated hydrocarbons. As a single compound, however, toluene was the most abundant one, explaining 11% of the total VOC concentrations as an average of all the dataset. Among source categories, petroleum associated sources such as gasoline storage/filling stations, and laundry factory were identified as the most significant sources of aliphatic hydrocarbons, while aromatic VOCs were dominantly emitted from the sources handling organic solvents, such as painting booth, printing offices, and textile dyeing processes. However. there was no apparent pattern in terms of the contributions of eath group to the total VOCs concentrations in environmental sanitary facilities. It was also found that the activated carbon adsorption tower installed for the VOC emission control in some facilities do not show any effective performances, which may result in the increased VOC levels in the ambient atmosphere.

• Ocean and Polar Research
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• v.24 no.2
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• pp.167-175
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• 2002

Sediment from six piston cores from the East Sea (Sea of Japan) was analyzed for evidence of paleoceanographic changes and paleoclimatic variation. A distinct geochemical boundary is evident in major element concentrations and organic carbon content of most cores near the 10-ka horizon. This distinctive basal Holocene change is interpreted to be largely the result of changing sediment sources, an interpretation supported by TiO_2/Al_2O_3$ ratios. Organic carbon and carbonate contents also differ significantly between the Holocene and glacial intervals. The C/N ratio of organic matter is greater than 10 during the glacial period, but is less than 10 for the Holocene, suggesting that the influx of terrigenous organic matter was more volumetrically important than marine organic matter during glacial times. The chemical index of weathering (CIW) is higher for the Holocene than the glacial interval, and changes markedly at the basal Holocene geochemical boundary. Silt fractions are higher in the glacial interval, suggesting a strong effect of climate on silt particle transportation: terrigenous aluminosilicates and continental organic carbon transport were higher during glacial times than during the Holocene. Differences in sediment composition between the Holocene and glacial period are interpreted to have been climatically induced.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.109-114
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• 1990

The effect of different carbon and nitrogen compounds on the growth and sporula­tion of Curvularia clavata Alcorn (Herberium No. IMI264075) has been studied. All the carbon sources tried were well utilized by the pathogen though glucose, and sucrose supported the best growth while glucose, maltose and sucrose the sporulation of the fungus. Of the nine nitrogen compounds, L-glutamic acid supported the best growth while aspartic acid and L-glutamic acid the sporulation of the fungus. Growth and sporulation were generally better with organic than inorganic nitrogen sources. Ammonium sulphate was the best inorganic source. A sudden drop of pH value of the culture media after 4 days of incubation did not favour good growth of the fungus.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.36-42
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• 2007

Korean paddy soils have long been almost uniformly managed throughout the whole country with flooded, deep tillage, puddlling, transplanting, and uncovering after harvest. Management of soil organic carbon could be more important in the sources of green house gases. However, soil organic carbon dynamics were not been studied for Korean paddy soils. Therefore, we evaluated the changes in soil organic carbon (SOC) of paddy soils between 1999 and 2003 at the same locations nationwide except islands. Soil organic carbon tends to increase in Inceptisols, which is predominant soil order for Korean paddy soils, from 1999 to 2003. Soil organic carbon increases in topographically plain paddy soils was greater than in valley soils, and was considerably high in predominant types of paddy soils (i.e., well adapted paddy soils, sandy paddy soils, and poorly drained paddy soils) but low and stable in the saline paddy soils. We also found that clay paddy soils are greater in soil organic carbon than sandy paddy soils. Through this study, we concluded that a proper management of paddy soils could contribute to soil organic carbon storage, which imply that the Korean paddy soils could help to enhance carbon dioxide sequestration via soil organic matter into the soil.

• Journal of Korean Society on Water Environment
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• v.34 no.5
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• pp.487-493
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• 2018

Urban stormwater runoff is the one of the most extensive causes of deterioration of water quality in streams in urban areas. Especially, in the Suyeong River watershed, non-point sources from urban-residential areas are the most common cause of water pollution. Also, it has been ascertained that BOD and COD as indexes of organic matter, have limitation on management of Suyeong River's water quality. In this study, changes of organic matter properties of Suyeong River from inflow of non-point source during rainfall were investigated. Fractions of organic matters were analyzed using water samples collected at two sites (Suyeong River and Oncheon Stream) during a rain event. Variations of dissolved organic carbon (DOC) concentration by rainfall were similar to flow rate change in the river. Distribution of organic matter fraction according to change of rain duration revealed that while hydrophilic component increased at initial rainfall, the hydrophobic component was similar to change in dissolved organic carbon (DOC) concentration. Also, the relative proportion of hydrophilic components in organic matter in river water increased, due to rainfall. Results of biodegradation of organic matters revealed that decomposition rate of organic matters during rainfall was higher than that of during a non-rainfall event.