• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.9
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• pp.1232-1238
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• 2018

This paper proposes methods for improving mass spectral resolution for a gas chromatograph mass spectrometer. The slope signs of the 1st and 2nd fitting functions for the ion signal block of each mass index are obtained, and the unnecessary element signals in the ion signal block are removed. The spectrum can be obtained by obtaining the second-order fitting function of the reconstructed ion signal block using only the effective ion signals. In addition, the resolution of the mass spectrum can be improved by correcting the error caused by the shift of the spectral peak position. To verify the performance of the proposed methods, computer simulations were performed using the actual ion signals obtained from the GC-MS system under development. Simulation results show that the proposed method is valid.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.14-20
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• 2011

Objective of this research was to investigate the volatile aroma compounds and phenol contents for preservative effects. Aerial part of 5 Korean natured species of thyme located in Jeju alpine, jeju middle mountain, Kyeonggido, Ulleung island, and Gangwondo was analyzed by thermal desorption gas chromatograph mass spectrometer (TD-GC-MSD) method. Jeju middle mountain thyme was relatively high 62 species and has been investigated a high concentration of $7365.22{\mu}g/m^3$ contents according to the quantitative analysis. Total phenol contents containing thymol and carvacrol of Jeju middle mountain thyme were relatively high and showed 35.92%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.543-545
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• 2002

The volatile compounds in kimchi adsorbed with solid phase microextraction (SPM) were analyzed by using a gas chromatograph-atomic emission detector (GC-AED) and a gas chromatograph-mass spectrometer (GC-MSD). The volatile compounds were effectively adsorbed in SPME. Twenty five compounds such as dimethyl-sulfide were identified by GC-MSD and some of these were further confirmed to contain a sulfur and a nitrogen by GC-AED.

• Analytical Science and Technology
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• v.12 no.6
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• pp.571-576
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• 1999

Screening method for NSAIDs (Hon-Steroidal Anti-Inflammatory Drugs) in urine was developed using GC/NCI-MS. Derivatized six fenamates with pentafluoropropionic anhydride showed high sensitivity in NCI-MS. The conditions of the derivatization reaction and chromatographic conditions were established for screening with a trace analysis. Limit of detection was in the range of 4-25 pg/mL. This method may be used to the equine doping analysis for NSAIDs and forensic analysis.

• Fire Science and Engineering
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• v.28 no.4
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• pp.64-72
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• 2014

Flammable liquids residues in fire debris and pyrolysis products of flammable materials were analyzed by using Gas detecting tube, Gas Chromatograph/Mass Spectrometers (GC/MS), and Pyrolyzer. Comparison studies between chemical components detected in debris fired with and without Flammable liquids were performed. Though Flammable liquids were not present in debris, Gas detecting tube colors were also changed. Chemical components produced from conventional combustions were different from those produced from pyrolysis. Due to the difference of the reaction conditions between combustions and pyrolysis, different chemical products were produced. Petrochemical products of PVC wood-linoleum block could produce ignitable chemicals, such as toluene, ethylbenzene, undecane, and dodecane. So, for better fire investigation more consideration of those chemicals will be porformed.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E2
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• pp.89-97
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• 2003

Ambient polycyclic aromatic hydrocarbons (PAHs) were measured during the winter and summer of 2002 in Chongju. A filter pack and polyurethane foam (PUF) system was employed to collect simultaneously the particulate and gas phase PAHs. The samples were then analyzed using a gas chromatograph equipped with mass spectrometer detectors (GC/MSD). A total of 29 samples were collected and 11 PAH species were identified. The lower molecular weight PAH compounds (3∼4 rings) dominated the total PAH mass. The higher molecular weight PAH compounds (5∼6 rings) were less abundant. The PAHs were showed to exhibit seasonal variations. The concentrations of all com-pounds were significantly higher in winter than summer. The lower molecular weight PAHs were mostly found in the gas phase whereas the heavier ones were mainly associated with particulate phase. Vehicle emissions are likely to be the primary contributor of PAHs in Chongju. This study also demonstrated that it is necessary to perform simultaneously particulate and gas phase measurements to determine the accurate concentrations of ambient PAHs.

• Journal of the Korean Wood Science and Technology
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• v.14 no.2
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• pp.21-28
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• 1986

A quartz type gasification reactor was designed and used for pyrolysis and gasification of sawdust, ricestraw and ricehusk. The initial reaction temperature was 350$^{\circ}C$, and up to 550$^{\circ}C$ to complete pyrolysis and gasification reaction. In order to examine the effect of catalyst on reaction temperature, $K_2CO_3$ and $Na_2CO_3$ as catalyst were also used. The product gas mixtures are identified to be CO, $CO_2$, $CH_4$ and $CH_3CHO$ etc. by Gas Chromatography and Mass Spectrometer. The highest gas volume of the gasified sawdust at 550$^{\circ}C$ amounts to 1800ml/g of sawdust, even though the yield and composition of this product gas are depending on the reaction temperature of the reactor and catalyst used.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.457-466
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• 2017

Objectives: This study was carried out to investigate the characteristics of volatile organic compounds (VOCs) emitted from sewerage facilities such as a sanitary sewers, outlets, and catch basins. In addition, the dominant malodorous VOCs among the compounds in this study were studied. Methods: Waste gas samples were collected at 27 points in a sanitary sewer in commercial and residental areas. The concentrations of seven volatile organic compounds, including benzene and toluene, in the samples were analyzed by gas chromatograph mass spectrophotometer (GC/MS). Odor concentrations were estimated using the concentration data of the VOCs and each compound's threshold limit value. Results: As a result, it appeared that the average concentration of total observed data for acetaldehyde was 15.98 ppb and benzene 1.87 ppb, toluene 82.31 ppb, ethyl benzene 63.12 ppb, m+p-xylene 15.66 ppb, oxylene 18.73 ppb, and styrene 4.39 ppb. VOC concentrations in the commercial area were higher than those in the residential area. VOC concentrations of waste gas emitted from sewer lines was also higher than those at the outlet and in the catch basins. It was estimated that the main malodorous VOC among the seven VOCs was acetaldehyde. Conclusions: As there is little data on VOC concentrations inside sewer facilities in Korea, these data will be helpful for estimating impact assessment of VOCs and establishing a counter-plan for the abatement of VOCs from sewer facilities in the future.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.07a
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• pp.394-399
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• 2002

국민소득의 증대와 함께 소비자의 고품질 농축산물에 대한 수요와 관심이 날로 증가하고 있다 이에 따라 안전하며 고품질인 농축산물을 소비자에게 공급하기 위하여 안전한 농축산물의 생산, 신선도 유지를 위한 유통구조의 개혁, 품질 및 안전성 평가기술개발을 위한 노력이 보다 더 요구되고 있다. 소비자가 믿고 구매하기 위해서는 농축산물에 대한 품질보증이 필수적이며 이를 위해서는 신속하고 정확한 품질 및 유해물질의 판정기술 개발이 필요하다. 많은 농축산물에 있어서 주요 품질인자인 숙도 및 신선도의 변화는 휘발성 화학물질로 이루어진 냄새의 변화로 나타나므로 이를 측정하여 품질 및 안전성을 간접적으로 판정할 수 있다 기존의 냄새에 의한 품질 판정은 판별전문가에 의한 관능평가법 또는 GC(Gas Chromatography)나 GC/MS(Gas chromatograph mass spectrometer)에 의하여 주로 이루어져 왔다. 하지만, 관능평가법의 경우 판별전문가의 개인적인 차이, 피로, 건강상태 등에 따라 판정의 객관성이 떨어질 우려가 있고, GC나 GC/MS를 이용할 경우 냄새분석에 많은 시간과 노력이 소요되는 문제점이 있다. (중략)

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1386-1391
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• 1999

The methanol extract of Gardenia jasminoides Ellis showed antimicrobial activity against bacteria and yeasts. The extract was successively purified with solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, octadecylsilane column chromatography. The purified active substance was isolated by high performance liquid chromatography. The isolated compound was 3,4-dihydroxybenzoic acid which was determined by mass spectrometer, gas chromatograph-mass spectrometer, $^{1}H-nuclear$ magnetic resonance, $^{13}C-nuclear$ magnetic resonance and two-dimensional nuclear magnetic resonance. The content of 3,4-dihydroxybenzoic acid was $32.7\;{\mu}g/g$ in dried fruits of Gardenia jasminoides Ellis.