• 분석과학
• /
• 제8권4호
• /
• pp.745-751
• /
• 1995

In this paper, several simulated devices were constructed for determining components of organic vapors emitting from decorative materials, daily use chemicals and from common behavior of human beings, such as smoking and cooking. The VOCs were preconcentrated on activated carbon and then desorbed by carbon disulphide. The results were obtained by GC/MS analysis and computer searching. It can be concluded that the categories of the sources and the components of organic vapors in indoor air are very complicated, and different sources of VOCs in indoor air have their own emission characteristics.

• 미생물학회지
• /
• 제19권2호
• /
• pp.63-77
• /
• 1981

The growth rate of yeast population (Saccharomyces uvarum) cultivated in the Knopp's modified medium (plus various carbon sources) appeared the highest value when the Knopp's minimal medium was treated to 1.5% with disaccharide such as maltose and sucrose. Also the treatment of lactose and raffinose resulted in polulation growth as to the population size in case of maltose and sucrose. However, the gorwth of yeast was not occurred at all when a polysaccharide, such as inulin, was added as carbon source. The growth from of yeast population in Knopp's modified medium are characterized by the fact that log phase continued 100hrs after inoculation and that stationary state phase appeared in general 250hrs after inoculation. Applying the various carbon sources to respiration substrate for yeast cell, the respiration rate of yeast showed the highest value in treatment of maltose and followed in order of raffinose, lactose, glucose, and sucrose. Determined the amount of poly-phosphate and turn over pathway of poly-phosphate according to culture phase of yeast, it is revealed that the yeast synthesized 3 types of poly phosphate (poly-P A,B, and C) and postulated that turn over pathway of poly-phosphate as follows ; Inorganic phosphate is converted into each kind of polyphosphates, and then one part of poly-P-C is converted into poly-P-B, the rest poly-p-C and poly-P-B are converted into poly-P-A. The synthesized poly-phosphate is considered to have a role as energy pool utilizing to synthesis of cellular organic materials. Of the 13 carbon sources used in this experiment, the useful carbon sources for biosynthesis of poly-phosphate and cellular organic materials are confirmed as disaccharide (maltose and sucrose) as well as glucose. Protein synthesis in yeast cell showed the two peaks on 6th and 8th day after inoculation ; nucleic acid on 2nd day (48hrs), carbohydrates on 2nd day (48hrs), and phospholipid on 2nd and 8th day after inoculation, respectively.

• Journal of the korean society of oceanography
• /
• 제35권2호
• /
• pp.124-127
• /
• 2000

The analysis of stable carbon isotope ratios for benthic fauna was applied to identify the source of carbon in benthic food webs in Youngil Bay, Korea. The ${\delta}^{13}$C values of 9 invertebrate species collected in this area showed a narrow range between -20.5 and -16.3%$_o$ with a mean of-18.1 (${\pm}$1.1)"%$_o$. The results suggest that the major source of organic carbon for the benthic fauna of the lower estuarine reaches and the oceanic sites is autochthonous marine particulate organic matter. The contribution of organic matter from terrestrial and riverine sources to the diet of the benthic fauna in this area appears to be minor, despite the considerable inflow of riverine waters.

• 생태와환경
• /
• 제53권2호
• /
• pp.138-147
• /
• 2020

The Singil Stream, flowing into an artificial lake, Lake Shihwa (South Korea), experiences a strong anthropogenic pressure with continuous organic matter (OM) inputs from rural, urban, and industrial areas. In this study, we investigated suspended particulate matter (SPM) and streambed sediments collected along the Singil Stream in 2014 and 2016, by applying a dual element approach (δ¹³C and δ¹⁵N) to identify OM sources. The SPM and streambed sediment samples from the indusrial area showed higher organic carbon and nitrogen concentrations (or contents) than those from the other areas, with distinctively lower δ¹⁵N values. Accordingly, our dual element approach indicates that the industrial area was the predominant OM source influencing OM quality and thus water quality of the Singil Stream flowing into Lake Shihwa during the study periods. However, further studies are necessary to better constrain OM sources in the Singil Stream since OM sources from the industrial area appear to be complex.

• 한국환경과학회지
• /
• 제25권10호
• /
• pp.1349-1368
• /
• 2016

Concentrations of fine particulate matter ($PM_{2.5}$) and several of its particle constituents measured outside homes in Houston, Texas, and Los Angeles, California, were characterized using multiple regression analysis with proximity to point and mobile sources and meteorological factors as the independent variables. $PM_{2.5}$ mass and the concentrations of organic carbon (OC), elemental carbon (EC), benzo-[a]-pyrene (BaP), perylene (Per), benzo-[g,h,i]-perylene (BghiP), and coronene (Cor) were examined. Negative associations of wind speed with concentrations demonstrated the effect of dilution by high wind speed. Atmospheric stability increase was associated with concentration increase. Petrochemical source proximity was included in the EC model in Houston. Area source proximity was not selected for any of the $PM_{2.5}$ constituents' regression models. When the median values of the meteorological factors were used and the proximity to sources varied, the air concentrations calculated using the models for the eleven $PM_{2.5}$ constituents outside the homes closest to influential highways were 1.5-15.8 fold higher than those outside homes furthest from the highway emission sources. When the median distance to the sources was used in the models, the concentrations of the $PM_{2.5}$ constituents varied 2 to 82 fold, as the meteorological conditions varied over the observed range. We found different relationships between the two urban areas, illustrating the unique nature of urban sources and suggesting that localized sources need to be evaluated carefully to understand their potential contributions to $PM_{2.5}$ mass and its particle constituents concentrations near residences, which influence baseline indoor air concentrations and personal exposures. The results of this study could assist in the appropriate design of monitoring networks for community-level sampling and help improve the accuracy of exposure models linking emission sources with estimated pollutant concentrations at the residential level.

• 한국대기환경학회지
• /
• 제29권6호
• /
• pp.722-733
• /
• 2013

Ground-based measurements were conducted from August 25 to September 8 of 2011 for understanding characteristics of carbonaceous aerosols measured at Gosan. Chemical components and their sources were discussed by analysis of organic compounds with identification of primary and secondary products in particulate matter. Thus, organic carbon (OC) and elemental carbon (EC) based on the carbonaceous thermal distribution (CTD), which provides detailed carbon signature characteristics relative to analytical temperature, was used to improve the carbon fractionation of the analytical method. In addition, organic compounds by gas chromatography technique with the backward trajectories were discussed for characteristics of carbonaceous aerosols. Different air-masses were classified related to the OC thermal signatures and the organic molecular markers such as aromatic acids and PAHs. We concluded that the aging process was influenced by the long-range transport from East Sea area.

• 유기물자원화
• /
• 제28권2호
• /
• pp.41-48
• /
• 2020

본 연구에서는 음식물류폐기물 건조공정에서 발생하는 응축수에 포함된 유기탄소를 추출하여 외부탄소원으로서 적용 가능성을 평가하였다. 응축수의 성상은 COD, TN, TP 및 TS는 각각 21,374 (±3,238.3) mg/L, 148 (±32.6) mg/L, 4.19 (±1.5) mg/L, 455.7 (±0.015) mg/L로 나타났으며, 응축수에 포함된 생분해성 유기물의 함량은 47%였다. 응축수에 포함된 유기탄소 추출을 위하여 증발 농축 및 감압 증발 농축의 방법을 사용하였다. 본 연구에서 총 8가지 조건에서 수행 되었으나, 4가지 조건 (1. 상압 (0mmHg), 110℃ 2. 감압 (-600mmHg), 70℃ 3. 감압 (-500mmHg), 80℃ 4. 감압(-600mmHg), 80℃)에서 추출이 가능한 것으로 나타났다. 추출 결과, 추출된 4가지 조건 모두에서 유입 부피의 약 10% 추출하였을 때, 추출물의 유기물 농도가 가장 높고 추출 시간 대비 추출된 유기물의 양이 가장 많은 것으로 나타났다. 응축수에 포함된 유기탄소의 추출 최적 조건은 감압 (-600mmHg), 80℃로 판단하였으며, 유입 부피의 10% 추출이 적합한 것으로 평가하였다. 이때, 추출 농도, 추출량, 추출 효율, 추출시간, BOD/TCOD, TVFAs/TCOD의 비율 및 NH₃-N의 값은 각각 174,200 mg/L, 8,710 mg, 46%, 10분, 0.97, 0.74, 75.5 mg/L로 나타났다. 따라서, 추출된 유기탄소는 외부탄소원으로 활용될 수 있을 것으로 판단된다.

• 한국환경과학회지
• /
• 제29권7호
• /
• pp.691-702
• /
• 2020

Carbon biomass of plankton community, Total Organic Carbon (TOC) and Chlorophyll a (chl.a) concentration were examined in the SeoNakdong river from January to December in 2014, to assess composition of phyto- and zoo-plankton variation, to certify the correlation between chl.a and TOC and to determine the level of contribution of plankton carbon content to TOC in the reservoir-river ecosystem. The correlation level between TOC and chl.a was low in the year 2014 but exceptionally was highly correlated only during the period with cyanobacterial bloom. The high level of contribution of plankton carbon content to TOC was attributed to cyanobacterial carbon biomass from May to November and to Cladocera carbon biomass from March to May, November and December despite of its low abundance. These results suggest that there were inter-relationships between phytoplankton, zooplankton and TOC and also subtle consistency of their properties through the year. These patterns should be discussed in relation to the physiochemical and biological characteristics of the environment, as well as to allochthonous organic matters from non-point pollution sources.

• 생태와환경
• /
• 제34권3호통권95호
• /
• pp.166-174
• /
• 2001

소양호로 유입되는 유기탄소량을 측정하였으며, 유기탄소 부하량에 대한 유기물 기원의 기여도를 계산하기위해서 내부생성유기탄소와 외부기원유기탄소를 측정하였다. 내부생성유기탄소는 EOC를 고려한 식물플랑크톤의 1차생산력으로부터 계산하였으며, 외부기원유기탄소는 유입수의 유기탄소 농도와 양어장의 유기탄소 배출량으로부터 구하였다. 1차생산력은 가두리 양식장이 설치된 1987견부터 증가하여 1995견가지 높은 분포를 보였으며 가두리가 철거된 1998년 이후 급격히 감소하였다. 내부생성유기탄소와 외부기원유기탄소의 부하는 여름철에 집중되었으며, 7${\sim}$9월에 연간 부하량의 43.2%와 71.7%가 각각 유입되었다. 1차생산력은 여름철에 $1,000\;mgC\;m^{-2}\;d^{-1}$ 이상으로 증가하였으며 겨울철에 비교적낮았다. 식물플랑크톤의 EOC배출율도 1차생산이 증가하여 수체의 DOC농도가 높은 여름철에 높았다. 전체조사기간동안 내부생성과 외부기원유기물의 평균적인 기여도는 각각 총부하량의 53.6%와 46.4%를 차지하였다. EOC 배출율은 1차생산력의 4.4${\sim}$21.2%를 차지하였으며, 1차생산력 산정에서 식물플랑크톤의 EOC 배출율이 고려되어야 할 것으로 보인다.

• 한국대기환경학회지
• /
• 제31권5호
• /
• pp.482-492
• /
• 2015

Ground-based measurements were conducted from January 6 to 12 of 2015 for understanding characteristics of nitrogen containing carbonaceous aerosols as 16 amino acids at the Mokpo National University, Korea. The detailed amino acid components such as Cystine ($(SCH_2CH(NH_2)CO_2H)_2$) and Methionine ($C_5H_{11}NO_2S$) and their sources were analyzed by High-Performance Liquid Chromatography with Fluorescence Detection (HPLC-FLD) for behavior of secondary products in particulate matter. In addition, organic carbon (OC) and elemental carbon (EC) based on the carbonaceous thermal distribution (CTD), which provides detailed carbon signature characteristics relative to analytical temperature, and water soluble organic carbon (WSOC) by total organic carbon (TOC) analyzer were used to understand the carbon compound behaviors. The backward trajectories were discussed for originations of carbonaceous aerosols as well. Different airmasses were classified with the amino acids and OC thermal signatures. The results can provide to understand the aging process influenced by the long-range transport from East Sea area.