• Analytical Science and Technology
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• v.17 no.1
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• pp.85-89
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• 2004

Fragrance components of lilac (Syringa vulgaris) blossom have been characterized in this paper. The accurate characterization of fragrances collected from lilac blossom was carried out by solid-phase trapping-solvent extraction and gas chromatography-ion trap mass spectrometry. According to lilac species, the chemical compositions were significantly different. Benzaldehyde, phenylacetaldehyde, and ${\alpha}$-farnesene were found as the predominant component of white lilac blossom whereas benzaldehyde, ${\alpha}$-pinene, and ocimene were those of pale purple lilac. The enantiomeric analysis of ${\alpha}$-pinene in lilac blossom was found in the form of ( ).

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2001.10a
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• pp.140-140
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• 2001

A sensitive analytical method based on gas chromatograpy-mass spectrometry with a selected ion monitoring (GC/MS-SIM) with the purge-and-trap concentration and with headspace method (in limited applications) was developed for determining of epichlorohydrin in canned beverages coated with epoxy resin. The calibration curve in the range of $0.5\sim50ng$ had correlation coefficient greater than 0.998 and a detection limit of $0.l\mug/L$ was obtained using a sample volume of 20ml. The predominant ions of epichlorohydrin produced in MSD using electron ionization(EI) were m/z 57 ([M-CI]+) and 62/64 $([M-CH_2O]+)$. In survey of epichlorohydrin in thirty commercial canned beverage samples, none of them was detected.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.292-302
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• 2005

Condition of Ion-Trap gas chromatography-mass spectrometry (GC-MS) for rapid screening of 206-pesticides residues in agricultural foodstuffs was optimized. As applying a wide-bore column (10 m${\times}$0.53 mm, DF 0.25 um) connected with a fused silica restrictor (0.6 m${\times}$0.1 mm), a significant retention time reduction was obtained. Additionally, the shape of peaks was sharper and higher than classical GC's and GC-MS's, which allowed lower detection limits. To easily manage many spectral data, both of Electron Ionization(EI) and Chemical Ionization(CI) techniques were adopted in screening procedure. At the following steps, MS-MS technique were used to confirm screened analytes in complicated matrices.

• Journal of Korean Society on Water Environment
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• v.20 no.3
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• pp.245-250
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• 2004

This study investigated the micropollutants present in raw water supplied for the several drinking water treatment plants in Seoul. The target sample waters were collected from the several sites, such as Jayang (JY), Kuui (KI), Paldang (PD) and Kangbuk (KB) at the Han-River stream. The analytical method used in this study enable us to detect about 300 kinds of chemicals commonly found in surface water at ppt level by GC-ion trap MS. In this study, the consideration on the analytic results focused on the four hazardous organics, such as benzenes, phenols, phthalates and pesticides. The numbers of each detected micropollutant were 1~8 kinds for benzenes, 1~7 kinds for phenols, 5~7 kinds for phthalates and 1~9 kinds for pesticides. For the pesticides, the higher concentration was detected in the water samples collected from PD and KB adjacent to the farming area, and at June and July, which is the busy farming season. The total concentrations of each micropollutants detected at all the sites were significantly lower than those of drinking water regulation in Korea as well as other advanced countries. However, the frequently detected micropollutants requires the steady and precise monitoring for the effective management of drinking water source.

• Analytical Science and Technology
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• v.28 no.1
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• pp.58-64
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• 2015

This study aimed to investigate the concentration distributions and formation characteristics of trihalomethanes (THMs) in drinking water supplies to rural communities. Water samples were collected twice from 40 rural households located on the outskirts of Chuncheon city of Gangwon Province in the summers of 2010 and 2011, and urban drinking water samples were collected from 20 faucets during the same period in 2011 for comparison purpose. Water temperature, pH, and residual chlorine (total and free) concentrations were measured in the field, and samples were analyzed for dissolved organic carbon (DOC) and THM concentrations in the laboratory. The average DOC concentrations in rural water samples were not greatly different between groundwater (n = 20) and surface water (n = 20) which were used as sources for drinking water (1.81 vs. 1.91 mg/L). However, the average concentrations of total THMs (TTHMs) in groundwater ($9.77{\mu}g/L$) were much higher than those in surface water ($2.85{\mu}g/L$) and similar to those in urban drinking water samples ($10.8{\mu}g/L$). Unlike urban water supply, rural water (particularly groundwater) contained more brominated THM species such as dibromochloromethane (DBCM), suggesting its relatively high content of bromide ion (Br-). This study showed that rural water supplies have different THM formation characteristics from urban water supplies, probably due to their differences in source water quality properties.