• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.199-201
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• 2005

This paper describes a simple procedure for the quantitative analysis of 7 PCBs (polychlorinated biphenyls) in soils on the waste reclaimed land, The procedure involved sample clean up using silicagel column, acetonitrile partition and sulfuric acid procedures. The instrumental technique is applied GC/PDD(gas chromatography/pulsed discharge detector) and GC/ECD(gas chromatography/electron capture detector). Concentration of $sub-{\mu}g/g$ level was attainable with 20g soils on the waste reclaimed land.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3395-3398
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• 2010

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.11-12
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• 2003

• Journal of Plant Biology
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• 제37권4호
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• pp.411-415
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• 1994

In immature seeds of Phaseolus vulgaris, the presence of threee new 2-deoxy type brassinosteroids (trihydroxybrassinosteroids) have been demonstrated. These less polar brassinosteroids have been demonstrated. These less polar brassinosteroids have been tentatively characterized to be (3ξ, 22ξ, 23ξ)-2-deoxy-25-methylodolicholide, (3ξ, 22ξ, 23ξ)-2-deoxoy-dolichosterone and (3ξ, 22ξ, 23ξ)-2-deoxy-24-ethylbrassinone by analysis of gas chromatography-mass spectrometry. Their less biological activity and oxidation state than those of tetrahydroxybrassinosteroids suggest that they are potent biosynthetic precusors of tetrahydroxybrassinosteroids.

• Archives of Pharmacal Research
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• 제27권1호
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• pp.25-30
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• 2004

Combinatorial homoserine lactone mixtures and individual products were obtained from the methionine-functionalized resin in solid-phase synthesis. The four-step process consisting of a coupling step of an N-Fmoc-L-methionine, deprotection of N-Fmoc group, N-coupling with a carboxylic acid, and cleavage reaction through a polymer supported strategy is described. Gas chromatography-mass selective detector (GC-MSD) techniques provide the most powerful methods for identifying both the combinatorial mixtures and individual products.

• Bulletin of the Korean Chemical Society
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• 제10권2호
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• pp.196-200
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• 1989

Some s-triazine herbicides, namely simazine, atrazine, and propazine present as trace components in a complex mixture were analyzed by GC/MS and GC/MS/MS methods. Even though monitoring the molecular ions was the best in terms of sensitivity, adequate analysis could not be done when interfering species were present. When doubly charged ions which appeared at characteristic m/z values were monitored, chromatograms were rather free from interference. More importantly, selected reaction monitoring was found to provide a selective means of detection with general applicability.

• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.164-169
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• 1998

Vulcanized rubber containing three kinds of oligomeric resins such as cashew resin, t-octylphenol formaldehyde resin and terpene modified wood rosin has been characterized by simultaneous pyrolysis methylation-gas chromatography/mass spectrometry (SPM-GC/MS). After methylation by the SPM method using tetramethylammonium hydroxide, the methylated pyrolyzates of the corresponding resins were detected with higher sensitivity than underivatized pyrolyzates without any interferences from other ingredients of vulcanized rubber.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.314.1-314.1
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• 2003

Examination was made of the urinary metabolite(s) of CKD-712, which is a chiral compound, named S-YS49 derived from higenamine (one component of Aconite spp.) derivatives. First of all. to analyze the metabolite(s) of CKD-712, a simple and sensitive detection method for CKD-712 was developed by using gas chromatography-mass spectrometry(GC/MS). (omitted)

• 한국환경농학회지
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• 제1권1호
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• pp.14-21
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• 1982

N-Methylcarbamate계(系) 농약(農藥)의 잔류분석법(殘留分析法)을 확립(確立)하기 위하여 MIPC, XMC, BPMC, propoxur, carbofuran 및 carbary에 대하여 diazo화(化)에 의한 비색정량(比色定量)과 N-trifiuoroacetyl (TFA)화(化), pentafluorobenzyl ether(PFB)화(化) 및 dinitrophenyl ether (DNP)화(化)에 의한 유도체(誘導體)의 gas chromatography (ECD)法을 비교검토(比較檢討)하였다. 1) N-Methylcarbamate의 diazo화(化)에 의한 최대흡수파장(最大吸收波長)은 MIPC, XMC, BPMC, propoxur, carbofuran이 460 ㎚이었고 carbaryl은 510 ㎚이었다. 2) 비색법(比色法)에 의한 carbamate의 현미(玄米)와 사과중(中) 회수솔(回收率)은 명명(各各) $80{\sim}104%$, $98{\sim}120%$이었고, 50 g의 시료분석시(試料分析時) 최대검출한계(最大檢出限界)는 $0.03{\sim}0.05$ ppm의 범위(範圍)이었다. 3) Gas chromatography에 의한 carbamate의 분석(分析)에서는 DNP$0.01{\sim}0.2$ppm첨가시(添加時) 현미(玄米)에서 $74{\sim}94%$, 수도체(水稻體)에서 $78{\sim}93%$, 사과에서 $82{\sim}99%$의 범위(範圍)이었고 검출한계(檢出限界)는 50g의 시료분석시(試料分析時) TFA 0.01 ppm PFB 0.005ppm, DNP 0.01ppm이었다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 추계 학술대회논문집
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• pp.21-26
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• 2005

Gas Chromatography (GC) is a wisely technique used for the separation and analysis of liquid and gas sample. Separation of the sample vapors is achieved via their differential migration through a capillary column with an insert carrier gas. The identity and quantity of each vapor in the mixer can be determined from its retention time in the column and a particular property of the gas, such as thermal conductivity, which can be related to the concentration of sample vapor in the carrier gas. Therefore, the flow characteristics in the spiral gas chromatographic column are numerically investigated in this study. Especially, different pressure drop between the front and the rear of GC column with various flow rates is estimated the governing equations are derived from making using of three-dimensional Naver-Stokes equation with incompressible and laminar model due to the nature of low Reynolds number flow. Using a commercial code, FLUENT, the pressure and flow fields in GC column are calculated with various flow rates. The characteristics of thermal cycling which is one of the most important factors affecting the column efficiency and analysis time is also estimated. Furthermore, numerical analyses are also carried out by using commercial code, ANSYS, with various values of power, which is applied to the heating element located at lower GC column.