• Applied Biological Chemistry
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• 제45권2호
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• pp.97-100
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• 2002

Phthalate ester는 플라스틱의 물리적 성질, 특히 유연성을 향상시키기 위하여 플라스틱 제품에 첨가하는 가소제이며 내분비계 장애를 일으키는 것으로 추정되는 물질이다. 본 연구에서는 우리나라 한강지류 하천 주변 토양의 phthalate esters의 오염 정도를 gas chromatography-mass spectrometry(GC-MS) 방법으로 분석하였다. 그 결과 예상 오염 지역인 안양천과 서호천, 그리고 예상 청정 지역인 가평천과 남한강 지역에서 채취한 토양시료 모두에서 bis(2-ethylhexyl) phthalate(DEHP)가 일정 수준 검출되었다. 그 오염 수준은 안양천 주변 토양이 113ppb로 가장 높았으며, 서호천 주변 토양이 64 pub,그리고 가평천과 남한강 주변 토양이 약 50 ppb이었다. 따라서 한강 지류 하천 토양의 DEHP오염은 국내 하천 저질의 DEHP오염 수준이 최고 2.04 ppm임을 감안할 때 상대적으로 낮은 수준임을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.35-42
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• 2009

Headspace micro solid phase extraction using mulberry paper bag (HS-MPB-$\mu$-SPE) has been developed and validated for the analysis of volatile flavor compounds from five spice by gas chromatography-mass spectrometry (GC/MS). HS-MPB-$\mu$-SPE was performed with adsorbent particles enclosed inside a mulberry paper bag. Four different kinds of adsorbents such as Tenax TA, Porapack Q, dimethylpolysiloxane and polyethylene glycol were tested. The extraction solvents compared were petroleum ether, methylene chloride, and chloroform. Better results were obtained when Tenax TA and petroleum ether were used. The limit of detection (LOD) and the limit of quantitation (LOQ) were in the range of 1.3 ng/mL and 4.3 ng/mL, respectively, for o-cymene as a model compound of monoterpene. Proposed method showed good reproducibility (3.3%, RSD) and good recoveries (94.0%). The HS-MPB- μ-SPE is very simple to use, inexpensive, rapid, requires small sample amounts and solvent consumption. Because the solvent for extraction is reduced to only a very small volume (0.6 mL), there is minimal waste or exposure to toxic organic solvent and no further concentration step. This method allows successful characterization of the headspace in contact with the five spice sample. Strong trans-anethole from star anise or fennel is a characteristic flavor of five spice powders. HS-MPB-$\mu$-SPE combined with GC/MS can be a promising technique for the broad spectrum measurement of volatile aroma compounds from solid spices.

• 분석과학
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• 제17권1호
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• pp.29-36
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• 2004

본 연구에서는 토양중에 존재하는 폴리브롬화 디페닐에테르 (polybrominated diphenyl ethers, PBDEs)를 동위원소희석법을 이용한 기체크로마토그래피/질량분석기-선택이온검색법에 의해 검출하는 분석방법을 소개하였다. 토양 중 PBDEs는 속실렛 장치로 추출하고 실리카와 플로리실 흡착제를 이용한 고체상 추출법을 비교하였다. 정제 후 추출물은 기체크로마토그래피/질량분석기-선택이온검색방법으로 분석하였으며, 동위원소로 치환된 4종의 PBDEs를 내부표준물질로 이용한 동위원소 희석법으로 8종의 PBDEs를 정량하였다. 속실렛추출 후 플로리실과 실리카 카트리지를 통한 회수율은 각각 30.8~110.8%, 44.4~110.7%이었다. 이 분석법의 검출한계는 0.04~0.3 ng/g로 나타났다.

• 한국축산식품학회지
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• 제43권3호
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• pp.471-490
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• 2023

In this study, the duck eggs were salted with none or 2.5% and 5.0% (v/v) of liquid smoke (LS), respectively. As a control, samples salted without LS were used. The 2-thiobarbituric acid (TBA) values, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, and reducing power of the three groups were tested at 0, 7, 14, and 21 and 28 days to determine the effects of LS on the antioxidant activity of treated eggs. In addition, gas chromatography-mass spectrometry (GC-MS) and electronic nose (E-Nose) were used to analyze the volatile flavor components of fresh duck eggs, LS, control, and salted duck eggs enriched with 2.5% (v/v) LS after 28 days of salting. The TBA value considerably increased with an increase in salting period, and the treated egg's TBA value significantly associated with LS concentration. The TBA value decreased as the LS concentration increased. The amount of LS present was highly associated with their capacity to scavenge DPPH radicals. The reducing power of the samples was substantially correlated with the LS concentration, and the reducing power increased with increasing LS concentration. The GC-MS data revealed that phenols and ketones were the predominant chemicals present in the LS, and they were also found in the eggs added to the LS even though they were absent in the fresh eggs and control. The flavor of the control group and treated eggs with LS differed significantly, according to the principal component analysis and radar map of the E-nose. The texture study results revealed that the LS significantly impacted the hardness, cohesiveness, and chewiness of eggs.

• 한국식품과학회지
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• 제39권4호
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• pp.366-371
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• 2007

어육장의 휘발성 향기 성분들을 용매추출을 이용하여 분리, 농축하였으며, GC-MS로 분석하였다. 총 36가지의 휘발성 성분들이 검출되었으며, 11개의 aliphatic hydrocarbons, 4개의 acids, 2개의 ketones, 5개의 phenols, 7개의 alcohols, 1개의 pyrazine, 4개의 pyrones와 furanones, 2개의 miscellaneous components 등으로 구성되어 있었다. 특히, acids인 butanoic acid가 높은 함량을 나타내었다. 어육장의 향기활성 성분을 규명하기 위해 용매추출을 이용하여 휘발성 성분들을 분리 후 향추출물 희석분석법으로 flavor dilution(FD) $factor(Log_3$ FD)를 구하였다. 이 결과 어육장에서 총 20종의 향기활성 성분들이 확인되었다. 이 중 군덕내의 특성을 지닌 butanoic acid와 구운 감자향을 지닌 methional이 높은 FD factor를 보였으며, 이들 성분 외에 높은$(Log_3$ FD>7)를 나타내는 성분들로는 2-methyl-2-butanol(soysauce-like), 3-hydroxy-2-butanone(buttery), 2-furanmethanol(burnt sugar-like) 등이 있었다. 본 실험에서는 어육장을 시료로 하여 휘발성 향기성분 및 향기활성 성분들을 GC-MS 및 AEDA법에 의해 분석함으로 어육장 특유의 향미특성을 규명하였다. 이는 앞으로 고급화된 장류 제품으로서는 물론, 다양한 식품에서 조미소재로의 어육장의 활용도를 높이는데 기여할 것이다.

• 센서학회지
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• 제23권5호
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• pp.320-325
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• 2014

Volatile flavor compounds from milk were analyzed and identified by using the analysis methods of headspace solid phase microextraction gas chromatography/mass spectrometry (HSPME-GC/MS) and electronic nose (E-Nose) system. About 30 volatile compounds were identified by HSPME-GC/MS for the fresh and off-flavor milk samples. Also, the correlation between rancidity and ageing days of milk was obtained by the aid of principal component analysis algorithm. It shows that the E-Nose system can identify the various types of milk flavor. These results imply that the analysis method based on the E-nose system can apply to the quality control of milk flavor and the rancidity.

• 공업화학
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• 제30권6호
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• pp.707-711
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• 2019

The feasibility of waste concrete as a catalyst for the effective pyrolysis of polyethylene terephthalate (PET) was examined using thermogravimetric (TG) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) analyses. TG analysis results indicated that the maximum decomposition temperature of PET is not altered by the use of waste concrete, showing similar values (407 ℃ and 408 ℃ at 5 ℃/min). Meanwhile, the volatile product distribution data obtained from the Py-GC/MS analysis revealed that the use of waste concrete promoted the deoxygenation reaction via converting the oxygen containing products such as benzoic acids, benzoates, and terephthalates to valuable deoxygenated aromatic hydrocarbons including benzene, toluene, ethylbenzene, and styrene. This suggests that the waste concrete can be used as a potential catalyst for the production of valuable aromatic hydrocarbons from PET pyrolysis.

• Elastomers and Composites
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• 제51권1호
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• pp.63-67
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• 2016

Poly(ethylene-co-vinyl acetate) (EVA) was pyrolyzed to eliminate acetic acid of VA unit using off-line pyrolysis, and the deacetylated EVA was analyzed infrared spectroscopy (IR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). EVA film for deacetylation was prepared by solution casting on aluminum foil and it was pyrolyzed at low temperature of $300^{\circ}C$ in the off-line pyrolysis apparatus. After deacetylation, carbon-carbon double bond (C=C) was formed by 1,2-elimination of the VA unit in the EVA backbone. Most of C=C bonds were trans-1,4-unit and 1,2-unit was also observed. Presence of the 1,2-unit in deacetylated EVA indicates that terminal or branch VA units exist in the raw EVA. Py-GC/MS chromatogram of deacetylated EVA displayed much smaller acetic acid and much more abundant other pyrolysis products than that of raw EVA, which means that the pyrolysis efficiency and separation condition were improved.

• 약학회지
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• 제47권5호
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• pp.266-270
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• 2003

We evaluated four commercially available methamphetamine immunoassays for their relative cross-reactivities of amphetamine analogues in human urine: Abbott TDx, Vitalab Selectra and on-site test kits (Accusign MET, SD bioline MET). High cross-reactivities were shown at designer's drugs such as methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA) and methylenedioxyethylamphetamine (MDEA) in all of the tested immunoassays. Methoxyphenamine, fenfluramine and phentermine were positive in TDx and Selectra, but were not positive in on-site test kits. Pseudoephedrine, norpseudoephedrine, ephedrine, norephedrine, MDMA, MDA, fenfluramine and phentermine were detected by gas chromatography/mass spectrometry(GC/MS) in false positive urines. Since the overall specificity of any of the devices was not 100％, we found it is important to confirm any positive screening test result, so we developed simultaneous determination of amphetamine analogues in urines. After alkalinization of the urine samples with 6-N NaOH, the analytes were extracted using ethyl acetate, derivatized with pentafluoropropyl anhydride (PFPA) prior at GC/MS analysis.

• 분석과학
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• 제17권6호
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• pp.527-531
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• 2004

Treatment with aqueous sodium hydroxide solution plays an important role to impart certain desirable properties - feel and luster on the surface of polyester fiber. In this process alkali wastewater contains disodium terephthalate, ethylene glycol (EG) and residual sodium hydroxide. In this paper we report a new method containing the pretreatments of derivatization with benzoyl chloride and solvent extraction using pentane. The calibration curve of EG determined by GC/MS-SIM shows a good linearity in the range of 0.1 to $25{\mu}g/mL$ having the standard deviation of ${\leq}8.7%$. The recovery and the detection limit of this method are 91.9-93.7% and $0.05{\mu}g/mL$ respectively.