• Environmental Analysis Health and Toxicology
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• v.20 no.2 s.49
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• pp.123-131
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• 2005

본 연구는 GC/MS를 이용하여 수질, 토양 및 저질 시료 중의 4-Nitrotoluene(4-NT)을 분석하는 방법을 확립하고자 하였다. 4-NT은 수질 시료(100mL)에서 n-hexane으로 추출하였으며, 토양 및 저질 시료(10g)에서는 먼저 메탄올로 추출한 후 hexane으로 다시 추출하여 농축시켜 분석하였다. 수질 시료 중의 4-NT의 회수율은 $99.1\%$ 이상이였으며 토양에서의 회수율(recovery)은 약 $110\%$를 보였고 재현성 (relative standard deviation)은 $11.99\%$ 이하였다. 검정곡선은 상관계수$(R^2)$값이 수질과 토양 모두에서 0.994이상의 좋은 직선성을 보여주었다. 본 연구에서 채취한 수질 43개 지역, 토양 35개 지역 및 저질 11개 지역의 모든 시료에서 4-NT은 검출한계 이하로 나타났다. 이 분석방법은 환경 중에 미량으로 존재하는 4-NT의 분석과 모니터링에 유용하게 사용할 수 있는 적합한 방법이라 사료된다.

• Analytical Science and Technology
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• v.7 no.1
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• pp.65-78
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• 1994

The herbicide mixture of 7 triazines and 9 phenoxyalkanoic acid esters was simultaneously separated and determinated with the selected ion monitoring by using gas chromatography/mass spectrometry. The extraction recoveries of those herbicides from the reagent water were studied for the organic solvent extraction(LLE) with methylene chloride. The calibration curves of them showed good linearity over the concentration range of 0.2~0.5ng/ml and the detection limits were 0.2~0.5ng/ml for 100ml of water. This analytical method could be applied to the drinking water and biological sample.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.513-523
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• 1995

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are the most concerned toxic organic pollutants to human. Because of their extremely high toxicity and uncertain genotoxic potential, their determination in environmental and biological samples is of great interest. Municipal solid waste incinerator facilities have been reported as the major contributors of dioxins and furans to the environment, and their formation from combustion is a universal phenomenon, everywhere. In this study dioxins and furans were analyzed from the bottom ash produced during combustion in an municipal waste incinerator located in Seoul. The EPA method was modified for sample pretreatment: the soxhlet method was used for extraction and clean-up procedures were performed by using silica and basic alumina, excluding active-carbon. The extract was then analyzed by HRGC/HRMS. A general trend of increase in the amounts of 6∼7 chlorine-substituted dioxins and furans was observed. Total dioxins, furans and 2,3,7,8-TCDD were determined as 8.05 ng/g, 4.75 ng/g, and 6.93 pg/g, respectively.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.166-177
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• 2022

The Shiveet Khairkhan is located on Tsengel Som in the middle of Bayan-ulgi Aimag in the Altai region. Various remains have been identified, and it has been found to be an important area of the Eurasian steppe. In this study, the characteristics of textile fibers and dyes excavated from the tombs of the 1st~3rd century Xianbei period in the sites of Shiveet Khairkhan, Mongolia were investigated. As a result of analysis using optical microscopic observation and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) for fiber identification, green and yellow fabrics were identified as silk fabrics. To investigate the properties of the dye, the surface reflectance of the dyed fabric was measured using an fiber optic reflectance spectrophotometer for non-destructive analysis. The green fabric appeared similar to the reflection spectrum of indigo dye. In addition, as a result of component analysis using gas chromatography-mass spectrometry, isatin and indigotine were detected. Isatin and indigotine are characteristic components of indigo dye, and it was found that the green fabric of the tombs of the Xianbei period was dyed using indigo dye. It was difficult to identify the type of dye in the yellow fabric as a result of reflectance spectrum and gas chromatography analysis. Indigo plants are a dye used for blue dyeing from thousands of years ago, and many species are distributed around the world. It was confirmed that the fabric was relatively well preserved and indigo dye was used for the green Jikryeongui (garment with a straight collar) in the ancient tomb of the Xianbei period about 1,800 years ago, even though it was buried for a long time. Scientific investigation of textile cultural heritage is an essential process for conservation treatment, restoration, exhibition, and the creation of a conservation environment. It is expected that related research will be activated in the future and will be helpful in interpreting the living culture at the time, preserving textiles, and a conservation environment.

• 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.

• Analytical Science and Technology
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• v.18 no.2
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• pp.147-153
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• 2005

Benzophenone (BP) which is one of endocrine disrupting chemicals is suspected to contaminate waters (river, lake and industrial drainage) and soils (ground soil and sediment). Analytical method for determination of BP in soil and water was developed by gas chromatography/mass spectrometry. Water sample (100 mL) was extracted with n-hexane, and soil (10 g) was extracted with methanol and n-hexane. Recovery for BP was >71.4% in water and 86.5-94.7% in soil with coefficient variation of less than 19.8%. Calibration curves showed a good linearity ($r^2$ >0.998). In water, soil and sediment collected at nation-wide sites, BP was detected at 5 sites among 43 water sites at the concentration range of 30-200 ng/L. No BP was found in the soil and sediment samples. It is suggested that this method will be useful to the determination of BP in the environmental matrices such as waters, soils and sediments in minute quantities.

• Analytical Science and Technology
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• v.14 no.5
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• pp.392-399
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• 2001

The analysis of n-butylbenzene and 1,2-dibromo-3-chloropropane (DBCP) as volatile organic compounds in biota samples was performed by gas chromatography/mass spectrometry-selected ion monitoring mode. The target compounds, n-butylbenzene and DBCP, in biota samples were extracted by headspace solid phase microextraction (SPME) with $100{\mu}m$ polydimethyl siloxane (PDMS) fiber and purge & trap method. The extraction recoveries of these compounds obtained by SPME was 85.8% for n-butylbenzene and 92.4% for DBCP, respectively. Each value of method detection limit were $0.15{\mu}g/kg$ and $0.05{\mu}g/kg$, respectively. While in the case of purge & trap method, the extraction recovery was 115.2% for n-butylbenzene, 80.9% for DBCP and method detection limit were $0.04{\mu}g/kg$ and $0.70{\mu}g/kg$, respectively. The extraction yields and detection limits of these compounds obtained by purge & trap were equivalent to those by SPME.

• Tribology and Lubricants
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• v.28 no.6
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• pp.315-320
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• 2012

For proper functioning, general machines usually need lubricant oil as a cooling, cleaning, and sealing agent at points of mechanical contact. The quality of lubricant oil can deteriorate during operation owing to various causes such as high temperature, combustion products and extraneous impurities. In this study, a heavy load stopped during operation, and the oil was analyzed to check whether any impurities were added. Extraction using acetonitrile followed by reaction with BSTFA(bistrimethylsilyl trifluoroacetamide) showed that, trimethylsilylated ethylene glycol was present in the lubricant oil. To quantify the ethylene glycol in the oil, deuterium-substituted ethylene glycol, which acted as an internal standard, was added to the sample and then extracted with the solvent. Next, the extract was reacted with the derivatizing agent(BSTFA) and then analyzed with GC/MS. The detection limit of this method was found to be $0.5{\mu}g/g$ and the recovery of oil containing $20,000{\mu}g/g$ of ethylene glycol was measured to be 94.8%. A damaged O-ring and eroded cylinder liner were found during the overhaul, which implied the leakage of coolant containing ethylene glycol into the lubricating system. The erosion of the cylinder liner was assumed to be due to cavitation of the coolant in the cooling system.

• Analytical Science and Technology
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• v.33 no.3
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• pp.134-142
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• 2020

Twenty-one allergy-induced aromatic material in children's products were analyzed using gas chromatography mass spectrometer(GC-MSD). The analytes were extracted using an automatic Soxhlet extractor, centrifuged for 10 minutes in a fast freezing centrifuge, and the supernatant was filtered with a syringe filter and then transferred into a 2 mL vial and injected in a split mode. In the established condition, the calibration curve showed linearity with a determination coefficient of 0.9981 or more. Sensitivity was 0.3145 ~ 1.6757, which showed a fairly wide range of sensitivity for each substance. The detection limit of the device was 0.0016 ~ 0.0423 ㎍/mL and the maximum detection limit was less than 0.05 ㎍/mL. The method detection limit ranged from 0.0030 ~ 0.0589 ㎍/mL. In addition, the limit of quantification ranged from 0.0096 to 0.1876 ㎍/mL, with precision ranging from 0.41 to 10.49 % and accuracy ranging from 83 to 116 %. The analytical method developed in this study was applied to commercial products.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.2
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• pp.89-95
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• 2017

Although the global coffee market is growing every year and the demand for coffee wrapping paper is increasing accordingly, research on the effect of PE material and PP material on the coffee aroma used in the sealant layer, which will directly contact the product, is lacking. In this study, we studied the change of aroma patterns and flavor materials by adding coffee to PP and PE pouches. In addition, we observed changes in aroma patterns depending on the temperature and the presence of the deoxidizer. As a result, it was found that the PP type packaging material was slightly better than the PE type packaging material, but the performance was hardly changed by the material. Rather, the change in the aroma pattern due to temperature was dominant rather than the material. It is ideal that refrigerated distribution ($4^{\circ}C$) is the best storage temperature and sales are done within a short period of time. Among the indicators, pyridine was the most suitable material to study and there are many data about pyridine. Therefore, it is expected that the results can be derived by using pyridine.