• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.41-47
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• 2017

After $SF_6$, which is being used in power equipment as an insulating material, is classified as one of the 6 major greenhouse gases, the maintenance and the refinement of used $SF_6$ started to get attention. In regard to this, KEPCO Research Institute (KEPRI) is developing $SF_6$ recovery and refinement technology starting with establishing a comprehensive $SF_6$ analysis system. With the analysis system, qualitative and quantitative analyses of the purity and the impurities of $SF_6$ before and after recovery, and before and after refinement have been carried out. The analysis system is comprised of GC-DID (Gas Chromatograph -Discharge Ionization Detector) for trace impurities analysis, GC-TCD (Thermal Conductivity Detector) for analyses of $SF_6$ purity and major impurities concentration from several hundred ppm up to percent range, GC-MSD (Mass Selective Detector) for analyses of impurities not included in standard gas, FT-IR (Fourier Transform-Infrared) Spectrometer for analysis of HF and $SO_2$, and moisture analyzer for analysis of moisture below 100 ppm. With this analysis system, complete analysis method of $SF_6$ has been established. This analysis system is being used in the maintenance of power equipment and the development of $SF_6$ recovery and refinement technologies. In this paper, the analysis results of four samples - gas and liquid phase $SF_6$ samples from a $SF_6$ refinement system before and after refinement are presented.

• Korean Journal of Veterinary Research
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• v.48 no.2
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• pp.131-137
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• 2008

Pesticides are extensively used for the control of crop pests in agriculture and forestry. Organophosphate (OP) and carbamate pesticides are especially effective for the control of a variety of harmful insects. However, these cholinesterase inhibitors are also dangerous to non-target organisms (wildlife and other animals) because of their high acute toxicity. Most poisonings by pesticides occur as a result of misuse or accidental exposure, but intentional killing of unwanted animals also occurs. At the request of a local autonomous entity, we investigated wild bird poisonings by pesticides from 2003 to 2007. The 207 suspicious samples of pesticide poisoning based on the necropsy were analyzed by GC/NPD, GC/FPD, or GC/MSD. We looked for trends in the identification of pesticides in wild birds thought to have died from poisoning. Pesticides were determined in 59% of the total samples analyzed. Phosphamidon and monochrotophos were the most common pesticides identified, which amounted to 77% of the subtotal. Other OP and carbamate pesticides were also found in various concentrations from dead wild birds. The determined rates of pesticides were as high as 86% and 76% in 2003 and 2006, respectively, during an outbreak of avian influenza in Korea.

• Preventive Nutrition and Food Science
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• v.18 no.2
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• pp.145-149
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• 2013

We tested for residual pesticide levels in dried vegetables in Seoul, Korea. A total of 100 samples of 13 different types of agricultural products were analyzed by a gas chromatography-nitrogen phosphate detector (GC-NPD), an electron capture detector (GC-${\mu}ECD$), a mass spectrometry detector (GC-MSD), and a high performance liquid chromatography- ultraviolet detector (HPLC-UV). We used multi-analysis methods to analyze for 253 different pesticide types. Among the selected agricultural products, residual pesticides were detected in 11 samples, of which 2 samples (2.0%) exceeded the Korea Maximum Residue limits (MRLs). We detected pesticide residue in 6 of 9 analyzed dried pepper leaves and 1 sample exceeded the Korea MRLs. Data obtained were then used for estimating the potential health risks associated with the exposures to these pesticides. The estimated daily intakes (EDIs) range from 0.1% of the acceptable daily intake (ADI) for bifenthrin to 8.4% of the ADI for cadusafos. The most critical commodity is cadusafos in chwinamul, contributing 8.4% to the hazard index (HI). This results show that the detected pesticides could not be considered a serious public health problem. Nevertheless, an investigation into continuous monitoring is recommended.

• Journal of Environmental Science International
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• v.15 no.8
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• pp.811-817
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• 2006

We were carried out to monitor pesticide residues in herbal medicine. In Korea Pharmacy, these are no critics for pesticides except 5 kinds of organic chlorines (BHC, DDT, Aldrin, Endrin, Dieldrin) and heavy metals. We analysed 53 kinds of pesticides consisted of 14 kinds of organochlorines, 20 kinds of organophosphoruses, and 19 kinds of pesticides estimated endocrine disruptor on 373 samples consisted with 30kinds of herbal medicine. In this study, Domestic, Chinese and Japanese herbal medicines were tested with GC/ECD, GC/NPD and then confirmed with GC/MSD. Recoveries were 75$\sim$l10% in ECD detector and 76$\sim$97% in NPD detector. Detection limits were 0.004$\sim$0.064ppm in ECD detector and 0.006$\sim$0.094ppm in NPD detector. Organochlorines and others were not detected in samples.

• Korean journal of food and cookery science
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• v.23 no.4 s.100
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• pp.413-422
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• 2007

In this study, changes in the volatile compounds of Artemisia capillaris essential oil were investigated under six different storage conditions for 6 months. The essential oil was collected by steam distillation and analyzed by a gas chromatography-mass selective detector (GC-MSD). Seventy-five volatile compounds were identified from the fresh essential oil of Artemisia capillaris. During storage, the total levels of aldehydes, alcohols, and ketones slightly decreased and the level of hydrocarbons greatly decreased; the total level of esters also decreased in the essential oil. Notably, the levels of carvacrol, eugenol, myrcene, 1,8-cineole, caryophyllene, coumarin, ${\alpha}-thujone$, ${\beta}-thujone$, borneol, and ${\gamma}-terpinene$, known as antioxidants and antimicrobial agents, decreased during storage. Finally, aerobic storage conditions caused greater reductions in some compounds even at low temperatures.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.119-123
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• 1999

Test of the optimum condition of solid phase micro extraction(SPME) was performed by use of 5 vol-atile components in dilute aqueous solution. Volatile components of Sancho(Zanthoxylum schinifolium) were isolated by SPME method and were analyzed by GC/MSD and compared with volatile compone-nts isolated by simultaneous distillation extraction (SDE) method. Total 31 components were identified by comparing gas chromatography retention time and mass spectral data. The major compounds were limonene geranyl acetate $\beta$-phellandrene phellandral mycene linalool rose oxide caproic acid and caprylic acid SPME sampling procedure was found to be a good method for qualitative analysis of the volatile components.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.2
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• pp.169-177
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• 2001

The concentrations of ambient volatile organic compounds (VOC) were investigated from the Kwangju area. A total number of sixty six sample were collected and analyzed during day/night periods from June to September 1999. Each of the canister sample ws analyzed for alkane and aromatic compounds using a GC/MSD sys-tem. The concentration of VOC in mean day/night time, when compared, was in the order: toluene(16%)> isobu-tane(14%)= acethylene(14%)> propane(12%)> ethane(11%)> butane(9%). The VOC concentrations were gene-rally higher during the daytime than the nighttime. The VOC with light weight(such as an alkane group, $C_2$-C(suh)5) showed generally higher concentrations during day/nighttime than the VOC with heavy weight (such as an aromatic group). High correlations were among the VOC emitted from the similar sources.

• Environmental Analysis Health and Toxicology
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• v.15 no.1_2
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• pp.45-51
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• 2000

Analytical method of 4-nitrotoluene (4-NT) in water was developed by 9as chromatography/mass selective detector/selected ion monitoring (GC/MSD/SIM). 4-NT was extracted with diethyl ether. Organic layer was washed with 5 % sodium chloride solution. The influence of solvent and evaporation condition on extraction of 4-NT were examined. The retention time of 4-NT peak was 7.72 min. Coefficient of variation (CV) of 4-NT (ng) within day and day-to-day was ranged from 7.0 to 14.6% and from 7.7 to 20.8%, respectively. Recovery of 4-NT was ranged from 84 to 109%, and detection limit of 4-H was lese than 1 ng/㎖.

• Journal of Environmental Science International
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• v.14 no.1
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• pp.81-89
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• 2005

As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds from inventory sources in Seongseo industrial area were concentrated and analyzed with thermal desorber/GC/MSD, and major malodorous compounds were estimated. Odor intensity and odor concentration was analyzed simultaneously During a period from November in 2002 to December in 2003, this study was conducted to evaluate malodor emission characterization in major treatment facilities. The major components were Dimethyl sulfide, Dimethyl disulfide, Methyl mercaptane, Ammonia, Benzene, Toluene, m,p-xylene, o-xylene, Styrene, 1,2,4­T.M.B and 1,3,5-T.M.B. Among the six major inventory sources, the odor unit concentration of Night-soil disposal facilities was the highest, $669\~2344\;ou/m^{3}.$

• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.66-70
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• 2000

The volatile components of Korea ginger were compared by using different isolation methods, head-space sampling procedure(HSSP), simultaneous distillation extrction(SDE) and soild pahse micro-extractions(SPME). Sixty-one components were identified by GC-MSD in the extracts obtained from each extraction methods. However, the components identified showed a difference in their composition wit the extraction methods. In the extract by HSSP, fifty-five components including a high volatile compound such as acetaldehyde, ethylacetate, 2,3-butandione were detected, and thirty-one components were identified in the extract by SPME. While, the low volatile components such as elemol, zingiberenol and ${\beta}$-eudesmol were detected only in the extract by SDE method. The results suggest that SDE method is the best for the analysis of low volatile components, whereas HSSP is a proper method for the analysis of high volatile components from natural resources.